1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * USB hub driver.
4  *
5  * (C) Copyright 1999 Linus Torvalds
6  * (C) Copyright 1999 Johannes Erdfelt
7  * (C) Copyright 1999 Gregory P. Smith
8  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
9  *
10  * Released under the GPLv2 only.
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/module.h>
16 #include <linux/moduleparam.h>
17 #include <linux/completion.h>
18 #include <linux/sched/mm.h>
19 #include <linux/list.h>
20 #include <linux/slab.h>
21 #include <linux/kcov.h>
22 #include <linux/ioctl.h>
23 #include <linux/usb.h>
24 #include <linux/usbdevice_fs.h>
25 #include <linux/usb/hcd.h>
26 #include <linux/usb/onboard_hub.h>
27 #include <linux/usb/otg.h>
28 #include <linux/usb/quirks.h>
29 #include <linux/workqueue.h>
30 #include <linux/mutex.h>
31 #include <linux/random.h>
32 #include <linux/pm_qos.h>
33 #include <linux/kobject.h>
34 
35 #include <linux/bitfield.h>
36 #include <linux/uaccess.h>
37 #include <asm/byteorder.h>
38 
39 #include "hub.h"
40 #include "otg_productlist.h"
41 
42 #define USB_VENDOR_GENESYS_LOGIC		0x05e3
43 #define USB_VENDOR_SMSC				0x0424
44 #define USB_PRODUCT_USB5534B			0x5534
45 #define USB_VENDOR_CYPRESS			0x04b4
46 #define USB_PRODUCT_CY7C65632			0x6570
47 #define USB_VENDOR_TEXAS_INSTRUMENTS		0x0451
48 #define USB_PRODUCT_TUSB8041_USB3		0x8140
49 #define USB_PRODUCT_TUSB8041_USB2		0x8142
50 #define USB_VENDOR_MICROCHIP			0x0424
51 #define USB_PRODUCT_USB4913			0x4913
52 #define USB_PRODUCT_USB4914			0x4914
53 #define USB_PRODUCT_USB4915			0x4915
54 #define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	BIT(0)
55 #define HUB_QUIRK_DISABLE_AUTOSUSPEND		BIT(1)
56 #define HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL	BIT(2)
57 
58 #define USB_TP_TRANSMISSION_DELAY	40	/* ns */
59 #define USB_TP_TRANSMISSION_DELAY_MAX	65535	/* ns */
60 #define USB_PING_RESPONSE_TIME		400	/* ns */
61 #define USB_REDUCE_FRAME_INTR_BINTERVAL	9
62 
63 /* Protect struct usb_device->state and ->children members
64  * Note: Both are also protected by ->dev.sem, except that ->state can
65  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
66 static DEFINE_SPINLOCK(device_state_lock);
67 
68 /* workqueue to process hub events */
69 static struct workqueue_struct *hub_wq;
70 static void hub_event(struct work_struct *work);
71 
72 /* synchronize hub-port add/remove and peering operations */
73 DEFINE_MUTEX(usb_port_peer_mutex);
74 
75 /* cycle leds on hubs that aren't blinking for attention */
76 static bool blinkenlights;
77 module_param(blinkenlights, bool, S_IRUGO);
78 MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
79 
80 /*
81  * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
82  * 10 seconds to send reply for the initial 64-byte descriptor request.
83  */
84 /* define initial 64-byte descriptor request timeout in milliseconds */
85 static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
86 module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
87 MODULE_PARM_DESC(initial_descriptor_timeout,
88 		"initial 64-byte descriptor request timeout in milliseconds "
89 		"(default 5000 - 5.0 seconds)");
90 
91 /*
92  * As of 2.6.10 we introduce a new USB device initialization scheme which
93  * closely resembles the way Windows works.  Hopefully it will be compatible
94  * with a wider range of devices than the old scheme.  However some previously
95  * working devices may start giving rise to "device not accepting address"
96  * errors; if that happens the user can try the old scheme by adjusting the
97  * following module parameters.
98  *
99  * For maximum flexibility there are two boolean parameters to control the
100  * hub driver's behavior.  On the first initialization attempt, if the
101  * "old_scheme_first" parameter is set then the old scheme will be used,
102  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
103  * is set, then the driver will make another attempt, using the other scheme.
104  */
105 static bool old_scheme_first;
106 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
107 MODULE_PARM_DESC(old_scheme_first,
108 		 "start with the old device initialization scheme");
109 
110 static bool use_both_schemes = true;
111 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
112 MODULE_PARM_DESC(use_both_schemes,
113 		"try the other device initialization scheme if the "
114 		"first one fails");
115 
116 /* Mutual exclusion for EHCI CF initialization.  This interferes with
117  * port reset on some companion controllers.
118  */
119 DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
120 EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
121 
122 #define HUB_DEBOUNCE_TIMEOUT	2000
123 #define HUB_DEBOUNCE_STEP	  25
124 #define HUB_DEBOUNCE_STABLE	 100
125 
126 static void hub_release(struct kref *kref);
127 static int usb_reset_and_verify_device(struct usb_device *udev);
128 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
129 static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
130 		u16 portstatus);
131 
portspeed(struct usb_hub * hub,int portstatus)132 static inline char *portspeed(struct usb_hub *hub, int portstatus)
133 {
134 	if (hub_is_superspeedplus(hub->hdev))
135 		return "10.0 Gb/s";
136 	if (hub_is_superspeed(hub->hdev))
137 		return "5.0 Gb/s";
138 	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
139 		return "480 Mb/s";
140 	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
141 		return "1.5 Mb/s";
142 	else
143 		return "12 Mb/s";
144 }
145 
146 /* Note that hdev or one of its children must be locked! */
usb_hub_to_struct_hub(struct usb_device * hdev)147 struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
148 {
149 	if (!hdev || !hdev->actconfig || !hdev->maxchild)
150 		return NULL;
151 	return usb_get_intfdata(hdev->actconfig->interface[0]);
152 }
153 
usb_device_supports_lpm(struct usb_device * udev)154 int usb_device_supports_lpm(struct usb_device *udev)
155 {
156 	/* Some devices have trouble with LPM */
157 	if (udev->quirks & USB_QUIRK_NO_LPM)
158 		return 0;
159 
160 	/* Skip if the device BOS descriptor couldn't be read */
161 	if (!udev->bos)
162 		return 0;
163 
164 	/* USB 2.1 (and greater) devices indicate LPM support through
165 	 * their USB 2.0 Extended Capabilities BOS descriptor.
166 	 */
167 	if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
168 		if (udev->bos->ext_cap &&
169 			(USB_LPM_SUPPORT &
170 			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
171 			return 1;
172 		return 0;
173 	}
174 
175 	/*
176 	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
177 	 * However, there are some that don't, and they set the U1/U2 exit
178 	 * latencies to zero.
179 	 */
180 	if (!udev->bos->ss_cap) {
181 		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
182 		return 0;
183 	}
184 
185 	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
186 			udev->bos->ss_cap->bU2DevExitLat == 0) {
187 		if (udev->parent)
188 			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
189 		else
190 			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
191 		return 0;
192 	}
193 
194 	if (!udev->parent || udev->parent->lpm_capable)
195 		return 1;
196 	return 0;
197 }
198 
199 /*
200  * Set the Maximum Exit Latency (MEL) for the host to wakup up the path from
201  * U1/U2, send a PING to the device and receive a PING_RESPONSE.
202  * See USB 3.1 section C.1.5.2
203  */
usb_set_lpm_mel(struct usb_device * udev,struct usb3_lpm_parameters * udev_lpm_params,unsigned int udev_exit_latency,struct usb_hub * hub,struct usb3_lpm_parameters * hub_lpm_params,unsigned int hub_exit_latency)204 static void usb_set_lpm_mel(struct usb_device *udev,
205 		struct usb3_lpm_parameters *udev_lpm_params,
206 		unsigned int udev_exit_latency,
207 		struct usb_hub *hub,
208 		struct usb3_lpm_parameters *hub_lpm_params,
209 		unsigned int hub_exit_latency)
210 {
211 	unsigned int total_mel;
212 
213 	/*
214 	 * tMEL1. time to transition path from host to device into U0.
215 	 * MEL for parent already contains the delay up to parent, so only add
216 	 * the exit latency for the last link (pick the slower exit latency),
217 	 * and the hub header decode latency. See USB 3.1 section C 2.2.1
218 	 * Store MEL in nanoseconds
219 	 */
220 	total_mel = hub_lpm_params->mel +
221 		max(udev_exit_latency, hub_exit_latency) * 1000 +
222 		hub->descriptor->u.ss.bHubHdrDecLat * 100;
223 
224 	/*
225 	 * tMEL2. Time to submit PING packet. Sum of tTPTransmissionDelay for
226 	 * each link + wHubDelay for each hub. Add only for last link.
227 	 * tMEL4, the time for PING_RESPONSE to traverse upstream is similar.
228 	 * Multiply by 2 to include it as well.
229 	 */
230 	total_mel += (__le16_to_cpu(hub->descriptor->u.ss.wHubDelay) +
231 		      USB_TP_TRANSMISSION_DELAY) * 2;
232 
233 	/*
234 	 * tMEL3, tPingResponse. Time taken by device to generate PING_RESPONSE
235 	 * after receiving PING. Also add 2100ns as stated in USB 3.1 C 1.5.2.4
236 	 * to cover the delay if the PING_RESPONSE is queued behind a Max Packet
237 	 * Size DP.
238 	 * Note these delays should be added only once for the entire path, so
239 	 * add them to the MEL of the device connected to the roothub.
240 	 */
241 	if (!hub->hdev->parent)
242 		total_mel += USB_PING_RESPONSE_TIME + 2100;
243 
244 	udev_lpm_params->mel = total_mel;
245 }
246 
247 /*
248  * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
249  * a transition from either U1 or U2.
250  */
usb_set_lpm_pel(struct usb_device * udev,struct usb3_lpm_parameters * udev_lpm_params,unsigned int udev_exit_latency,struct usb_hub * hub,struct usb3_lpm_parameters * hub_lpm_params,unsigned int hub_exit_latency,unsigned int port_to_port_exit_latency)251 static void usb_set_lpm_pel(struct usb_device *udev,
252 		struct usb3_lpm_parameters *udev_lpm_params,
253 		unsigned int udev_exit_latency,
254 		struct usb_hub *hub,
255 		struct usb3_lpm_parameters *hub_lpm_params,
256 		unsigned int hub_exit_latency,
257 		unsigned int port_to_port_exit_latency)
258 {
259 	unsigned int first_link_pel;
260 	unsigned int hub_pel;
261 
262 	/*
263 	 * First, the device sends an LFPS to transition the link between the
264 	 * device and the parent hub into U0.  The exit latency is the bigger of
265 	 * the device exit latency or the hub exit latency.
266 	 */
267 	if (udev_exit_latency > hub_exit_latency)
268 		first_link_pel = udev_exit_latency * 1000;
269 	else
270 		first_link_pel = hub_exit_latency * 1000;
271 
272 	/*
273 	 * When the hub starts to receive the LFPS, there is a slight delay for
274 	 * it to figure out that one of the ports is sending an LFPS.  Then it
275 	 * will forward the LFPS to its upstream link.  The exit latency is the
276 	 * delay, plus the PEL that we calculated for this hub.
277 	 */
278 	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
279 
280 	/*
281 	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
282 	 * is the greater of the two exit latencies.
283 	 */
284 	if (first_link_pel > hub_pel)
285 		udev_lpm_params->pel = first_link_pel;
286 	else
287 		udev_lpm_params->pel = hub_pel;
288 }
289 
290 /*
291  * Set the System Exit Latency (SEL) to indicate the total worst-case time from
292  * when a device initiates a transition to U0, until when it will receive the
293  * first packet from the host controller.
294  *
295  * Section C.1.5.1 describes the four components to this:
296  *  - t1: device PEL
297  *  - t2: time for the ERDY to make it from the device to the host.
298  *  - t3: a host-specific delay to process the ERDY.
299  *  - t4: time for the packet to make it from the host to the device.
300  *
301  * t3 is specific to both the xHCI host and the platform the host is integrated
302  * into.  The Intel HW folks have said it's negligible, FIXME if a different
303  * vendor says otherwise.
304  */
usb_set_lpm_sel(struct usb_device * udev,struct usb3_lpm_parameters * udev_lpm_params)305 static void usb_set_lpm_sel(struct usb_device *udev,
306 		struct usb3_lpm_parameters *udev_lpm_params)
307 {
308 	struct usb_device *parent;
309 	unsigned int num_hubs;
310 	unsigned int total_sel;
311 
312 	/* t1 = device PEL */
313 	total_sel = udev_lpm_params->pel;
314 	/* How many external hubs are in between the device & the root port. */
315 	for (parent = udev->parent, num_hubs = 0; parent->parent;
316 			parent = parent->parent)
317 		num_hubs++;
318 	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
319 	if (num_hubs > 0)
320 		total_sel += 2100 + 250 * (num_hubs - 1);
321 
322 	/* t4 = 250ns * num_hubs */
323 	total_sel += 250 * num_hubs;
324 
325 	udev_lpm_params->sel = total_sel;
326 }
327 
usb_set_lpm_parameters(struct usb_device * udev)328 static void usb_set_lpm_parameters(struct usb_device *udev)
329 {
330 	struct usb_hub *hub;
331 	unsigned int port_to_port_delay;
332 	unsigned int udev_u1_del;
333 	unsigned int udev_u2_del;
334 	unsigned int hub_u1_del;
335 	unsigned int hub_u2_del;
336 
337 	if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
338 		return;
339 
340 	/* Skip if the device BOS descriptor couldn't be read */
341 	if (!udev->bos)
342 		return;
343 
344 	hub = usb_hub_to_struct_hub(udev->parent);
345 	/* It doesn't take time to transition the roothub into U0, since it
346 	 * doesn't have an upstream link.
347 	 */
348 	if (!hub)
349 		return;
350 
351 	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
352 	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
353 	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
354 	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
355 
356 	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
357 			hub, &udev->parent->u1_params, hub_u1_del);
358 
359 	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
360 			hub, &udev->parent->u2_params, hub_u2_del);
361 
362 	/*
363 	 * Appendix C, section C.2.2.2, says that there is a slight delay from
364 	 * when the parent hub notices the downstream port is trying to
365 	 * transition to U0 to when the hub initiates a U0 transition on its
366 	 * upstream port.  The section says the delays are tPort2PortU1EL and
367 	 * tPort2PortU2EL, but it doesn't define what they are.
368 	 *
369 	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
370 	 * about the same delays.  Use the maximum delay calculations from those
371 	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
372 	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
373 	 * assume the device exit latencies they are talking about are the hub
374 	 * exit latencies.
375 	 *
376 	 * What do we do if the U2 exit latency is less than the U1 exit
377 	 * latency?  It's possible, although not likely...
378 	 */
379 	port_to_port_delay = 1;
380 
381 	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
382 			hub, &udev->parent->u1_params, hub_u1_del,
383 			port_to_port_delay);
384 
385 	if (hub_u2_del > hub_u1_del)
386 		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
387 	else
388 		port_to_port_delay = 1 + hub_u1_del;
389 
390 	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
391 			hub, &udev->parent->u2_params, hub_u2_del,
392 			port_to_port_delay);
393 
394 	/* Now that we've got PEL, calculate SEL. */
395 	usb_set_lpm_sel(udev, &udev->u1_params);
396 	usb_set_lpm_sel(udev, &udev->u2_params);
397 }
398 
399 /* USB 2.0 spec Section 11.24.4.5 */
get_hub_descriptor(struct usb_device * hdev,struct usb_hub_descriptor * desc)400 static int get_hub_descriptor(struct usb_device *hdev,
401 		struct usb_hub_descriptor *desc)
402 {
403 	int i, ret, size;
404 	unsigned dtype;
405 
406 	if (hub_is_superspeed(hdev)) {
407 		dtype = USB_DT_SS_HUB;
408 		size = USB_DT_SS_HUB_SIZE;
409 	} else {
410 		dtype = USB_DT_HUB;
411 		size = sizeof(struct usb_hub_descriptor);
412 	}
413 
414 	for (i = 0; i < 3; i++) {
415 		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
416 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
417 			dtype << 8, 0, desc, size,
418 			USB_CTRL_GET_TIMEOUT);
419 		if (hub_is_superspeed(hdev)) {
420 			if (ret == size)
421 				return ret;
422 		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
423 			/* Make sure we have the DeviceRemovable field. */
424 			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
425 			if (ret < size)
426 				return -EMSGSIZE;
427 			return ret;
428 		}
429 	}
430 	return -EINVAL;
431 }
432 
433 /*
434  * USB 2.0 spec Section 11.24.2.1
435  */
clear_hub_feature(struct usb_device * hdev,int feature)436 static int clear_hub_feature(struct usb_device *hdev, int feature)
437 {
438 	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
439 		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
440 }
441 
442 /*
443  * USB 2.0 spec Section 11.24.2.2
444  */
usb_clear_port_feature(struct usb_device * hdev,int port1,int feature)445 int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
446 {
447 	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
448 		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
449 		NULL, 0, 1000);
450 }
451 
452 /*
453  * USB 2.0 spec Section 11.24.2.13
454  */
set_port_feature(struct usb_device * hdev,int port1,int feature)455 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
456 {
457 	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
458 		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
459 		NULL, 0, 1000);
460 }
461 
to_led_name(int selector)462 static char *to_led_name(int selector)
463 {
464 	switch (selector) {
465 	case HUB_LED_AMBER:
466 		return "amber";
467 	case HUB_LED_GREEN:
468 		return "green";
469 	case HUB_LED_OFF:
470 		return "off";
471 	case HUB_LED_AUTO:
472 		return "auto";
473 	default:
474 		return "??";
475 	}
476 }
477 
478 /*
479  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
480  * for info about using port indicators
481  */
set_port_led(struct usb_hub * hub,int port1,int selector)482 static void set_port_led(struct usb_hub *hub, int port1, int selector)
483 {
484 	struct usb_port *port_dev = hub->ports[port1 - 1];
485 	int status;
486 
487 	status = set_port_feature(hub->hdev, (selector << 8) | port1,
488 			USB_PORT_FEAT_INDICATOR);
489 	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
490 		to_led_name(selector), status);
491 }
492 
493 #define	LED_CYCLE_PERIOD	((2*HZ)/3)
494 
led_work(struct work_struct * work)495 static void led_work(struct work_struct *work)
496 {
497 	struct usb_hub		*hub =
498 		container_of(work, struct usb_hub, leds.work);
499 	struct usb_device	*hdev = hub->hdev;
500 	unsigned		i;
501 	unsigned		changed = 0;
502 	int			cursor = -1;
503 
504 	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
505 		return;
506 
507 	for (i = 0; i < hdev->maxchild; i++) {
508 		unsigned	selector, mode;
509 
510 		/* 30%-50% duty cycle */
511 
512 		switch (hub->indicator[i]) {
513 		/* cycle marker */
514 		case INDICATOR_CYCLE:
515 			cursor = i;
516 			selector = HUB_LED_AUTO;
517 			mode = INDICATOR_AUTO;
518 			break;
519 		/* blinking green = sw attention */
520 		case INDICATOR_GREEN_BLINK:
521 			selector = HUB_LED_GREEN;
522 			mode = INDICATOR_GREEN_BLINK_OFF;
523 			break;
524 		case INDICATOR_GREEN_BLINK_OFF:
525 			selector = HUB_LED_OFF;
526 			mode = INDICATOR_GREEN_BLINK;
527 			break;
528 		/* blinking amber = hw attention */
529 		case INDICATOR_AMBER_BLINK:
530 			selector = HUB_LED_AMBER;
531 			mode = INDICATOR_AMBER_BLINK_OFF;
532 			break;
533 		case INDICATOR_AMBER_BLINK_OFF:
534 			selector = HUB_LED_OFF;
535 			mode = INDICATOR_AMBER_BLINK;
536 			break;
537 		/* blink green/amber = reserved */
538 		case INDICATOR_ALT_BLINK:
539 			selector = HUB_LED_GREEN;
540 			mode = INDICATOR_ALT_BLINK_OFF;
541 			break;
542 		case INDICATOR_ALT_BLINK_OFF:
543 			selector = HUB_LED_AMBER;
544 			mode = INDICATOR_ALT_BLINK;
545 			break;
546 		default:
547 			continue;
548 		}
549 		if (selector != HUB_LED_AUTO)
550 			changed = 1;
551 		set_port_led(hub, i + 1, selector);
552 		hub->indicator[i] = mode;
553 	}
554 	if (!changed && blinkenlights) {
555 		cursor++;
556 		cursor %= hdev->maxchild;
557 		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
558 		hub->indicator[cursor] = INDICATOR_CYCLE;
559 		changed++;
560 	}
561 	if (changed)
562 		queue_delayed_work(system_power_efficient_wq,
563 				&hub->leds, LED_CYCLE_PERIOD);
564 }
565 
566 /* use a short timeout for hub/port status fetches */
567 #define	USB_STS_TIMEOUT		1000
568 #define	USB_STS_RETRIES		5
569 
570 /*
571  * USB 2.0 spec Section 11.24.2.6
572  */
get_hub_status(struct usb_device * hdev,struct usb_hub_status * data)573 static int get_hub_status(struct usb_device *hdev,
574 		struct usb_hub_status *data)
575 {
576 	int i, status = -ETIMEDOUT;
577 
578 	for (i = 0; i < USB_STS_RETRIES &&
579 			(status == -ETIMEDOUT || status == -EPIPE); i++) {
580 		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
581 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
582 			data, sizeof(*data), USB_STS_TIMEOUT);
583 	}
584 	return status;
585 }
586 
587 /*
588  * USB 2.0 spec Section 11.24.2.7
589  * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
590  */
get_port_status(struct usb_device * hdev,int port1,void * data,u16 value,u16 length)591 static int get_port_status(struct usb_device *hdev, int port1,
592 			   void *data, u16 value, u16 length)
593 {
594 	int i, status = -ETIMEDOUT;
595 
596 	for (i = 0; i < USB_STS_RETRIES &&
597 			(status == -ETIMEDOUT || status == -EPIPE); i++) {
598 		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
599 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
600 			port1, data, length, USB_STS_TIMEOUT);
601 	}
602 	return status;
603 }
604 
hub_ext_port_status(struct usb_hub * hub,int port1,int type,u16 * status,u16 * change,u32 * ext_status)605 static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
606 			       u16 *status, u16 *change, u32 *ext_status)
607 {
608 	int ret;
609 	int len = 4;
610 
611 	if (type != HUB_PORT_STATUS)
612 		len = 8;
613 
614 	mutex_lock(&hub->status_mutex);
615 	ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
616 	if (ret < len) {
617 		if (ret != -ENODEV)
618 			dev_err(hub->intfdev,
619 				"%s failed (err = %d)\n", __func__, ret);
620 		if (ret >= 0)
621 			ret = -EIO;
622 	} else {
623 		*status = le16_to_cpu(hub->status->port.wPortStatus);
624 		*change = le16_to_cpu(hub->status->port.wPortChange);
625 		if (type != HUB_PORT_STATUS && ext_status)
626 			*ext_status = le32_to_cpu(
627 				hub->status->port.dwExtPortStatus);
628 		ret = 0;
629 	}
630 	mutex_unlock(&hub->status_mutex);
631 	return ret;
632 }
633 
usb_hub_port_status(struct usb_hub * hub,int port1,u16 * status,u16 * change)634 int usb_hub_port_status(struct usb_hub *hub, int port1,
635 		u16 *status, u16 *change)
636 {
637 	return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
638 				   status, change, NULL);
639 }
640 
hub_resubmit_irq_urb(struct usb_hub * hub)641 static void hub_resubmit_irq_urb(struct usb_hub *hub)
642 {
643 	unsigned long flags;
644 	int status;
645 
646 	spin_lock_irqsave(&hub->irq_urb_lock, flags);
647 
648 	if (hub->quiescing) {
649 		spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
650 		return;
651 	}
652 
653 	status = usb_submit_urb(hub->urb, GFP_ATOMIC);
654 	if (status && status != -ENODEV && status != -EPERM &&
655 	    status != -ESHUTDOWN) {
656 		dev_err(hub->intfdev, "resubmit --> %d\n", status);
657 		mod_timer(&hub->irq_urb_retry, jiffies + HZ);
658 	}
659 
660 	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
661 }
662 
hub_retry_irq_urb(struct timer_list * t)663 static void hub_retry_irq_urb(struct timer_list *t)
664 {
665 	struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
666 
667 	hub_resubmit_irq_urb(hub);
668 }
669 
670 
kick_hub_wq(struct usb_hub * hub)671 static void kick_hub_wq(struct usb_hub *hub)
672 {
673 	struct usb_interface *intf;
674 
675 	if (hub->disconnected || work_pending(&hub->events))
676 		return;
677 
678 	/*
679 	 * Suppress autosuspend until the event is proceed.
680 	 *
681 	 * Be careful and make sure that the symmetric operation is
682 	 * always called. We are here only when there is no pending
683 	 * work for this hub. Therefore put the interface either when
684 	 * the new work is called or when it is canceled.
685 	 */
686 	intf = to_usb_interface(hub->intfdev);
687 	usb_autopm_get_interface_no_resume(intf);
688 	kref_get(&hub->kref);
689 
690 	if (queue_work(hub_wq, &hub->events))
691 		return;
692 
693 	/* the work has already been scheduled */
694 	usb_autopm_put_interface_async(intf);
695 	kref_put(&hub->kref, hub_release);
696 }
697 
usb_kick_hub_wq(struct usb_device * hdev)698 void usb_kick_hub_wq(struct usb_device *hdev)
699 {
700 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
701 
702 	if (hub)
703 		kick_hub_wq(hub);
704 }
705 
706 /*
707  * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
708  * Notification, which indicates it had initiated remote wakeup.
709  *
710  * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
711  * device initiates resume, so the USB core will not receive notice of the
712  * resume through the normal hub interrupt URB.
713  */
usb_wakeup_notification(struct usb_device * hdev,unsigned int portnum)714 void usb_wakeup_notification(struct usb_device *hdev,
715 		unsigned int portnum)
716 {
717 	struct usb_hub *hub;
718 	struct usb_port *port_dev;
719 
720 	if (!hdev)
721 		return;
722 
723 	hub = usb_hub_to_struct_hub(hdev);
724 	if (hub) {
725 		port_dev = hub->ports[portnum - 1];
726 		if (port_dev && port_dev->child)
727 			pm_wakeup_event(&port_dev->child->dev, 0);
728 
729 		set_bit(portnum, hub->wakeup_bits);
730 		kick_hub_wq(hub);
731 	}
732 }
733 EXPORT_SYMBOL_GPL(usb_wakeup_notification);
734 
735 /* completion function, fires on port status changes and various faults */
hub_irq(struct urb * urb)736 static void hub_irq(struct urb *urb)
737 {
738 	struct usb_hub *hub = urb->context;
739 	int status = urb->status;
740 	unsigned i;
741 	unsigned long bits;
742 
743 	switch (status) {
744 	case -ENOENT:		/* synchronous unlink */
745 	case -ECONNRESET:	/* async unlink */
746 	case -ESHUTDOWN:	/* hardware going away */
747 		return;
748 
749 	default:		/* presumably an error */
750 		/* Cause a hub reset after 10 consecutive errors */
751 		dev_dbg(hub->intfdev, "transfer --> %d\n", status);
752 		if ((++hub->nerrors < 10) || hub->error)
753 			goto resubmit;
754 		hub->error = status;
755 		fallthrough;
756 
757 	/* let hub_wq handle things */
758 	case 0:			/* we got data:  port status changed */
759 		bits = 0;
760 		for (i = 0; i < urb->actual_length; ++i)
761 			bits |= ((unsigned long) ((*hub->buffer)[i]))
762 					<< (i*8);
763 		hub->event_bits[0] = bits;
764 		break;
765 	}
766 
767 	hub->nerrors = 0;
768 
769 	/* Something happened, let hub_wq figure it out */
770 	kick_hub_wq(hub);
771 
772 resubmit:
773 	hub_resubmit_irq_urb(hub);
774 }
775 
776 /* USB 2.0 spec Section 11.24.2.3 */
777 static inline int
hub_clear_tt_buffer(struct usb_device * hdev,u16 devinfo,u16 tt)778 hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
779 {
780 	/* Need to clear both directions for control ep */
781 	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
782 			USB_ENDPOINT_XFER_CONTROL) {
783 		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
784 				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
785 				devinfo ^ 0x8000, tt, NULL, 0, 1000);
786 		if (status)
787 			return status;
788 	}
789 	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
790 			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
791 			       tt, NULL, 0, 1000);
792 }
793 
794 /*
795  * enumeration blocks hub_wq for a long time. we use keventd instead, since
796  * long blocking there is the exception, not the rule.  accordingly, HCDs
797  * talking to TTs must queue control transfers (not just bulk and iso), so
798  * both can talk to the same hub concurrently.
799  */
hub_tt_work(struct work_struct * work)800 static void hub_tt_work(struct work_struct *work)
801 {
802 	struct usb_hub		*hub =
803 		container_of(work, struct usb_hub, tt.clear_work);
804 	unsigned long		flags;
805 
806 	spin_lock_irqsave(&hub->tt.lock, flags);
807 	while (!list_empty(&hub->tt.clear_list)) {
808 		struct list_head	*next;
809 		struct usb_tt_clear	*clear;
810 		struct usb_device	*hdev = hub->hdev;
811 		const struct hc_driver	*drv;
812 		int			status;
813 
814 		next = hub->tt.clear_list.next;
815 		clear = list_entry(next, struct usb_tt_clear, clear_list);
816 		list_del(&clear->clear_list);
817 
818 		/* drop lock so HCD can concurrently report other TT errors */
819 		spin_unlock_irqrestore(&hub->tt.lock, flags);
820 		status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
821 		if (status && status != -ENODEV)
822 			dev_err(&hdev->dev,
823 				"clear tt %d (%04x) error %d\n",
824 				clear->tt, clear->devinfo, status);
825 
826 		/* Tell the HCD, even if the operation failed */
827 		drv = clear->hcd->driver;
828 		if (drv->clear_tt_buffer_complete)
829 			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
830 
831 		kfree(clear);
832 		spin_lock_irqsave(&hub->tt.lock, flags);
833 	}
834 	spin_unlock_irqrestore(&hub->tt.lock, flags);
835 }
836 
837 /**
838  * usb_hub_set_port_power - control hub port's power state
839  * @hdev: USB device belonging to the usb hub
840  * @hub: target hub
841  * @port1: port index
842  * @set: expected status
843  *
844  * call this function to control port's power via setting or
845  * clearing the port's PORT_POWER feature.
846  *
847  * Return: 0 if successful. A negative error code otherwise.
848  */
usb_hub_set_port_power(struct usb_device * hdev,struct usb_hub * hub,int port1,bool set)849 int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
850 			   int port1, bool set)
851 {
852 	int ret;
853 
854 	if (set)
855 		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
856 	else
857 		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
858 
859 	if (ret)
860 		return ret;
861 
862 	if (set)
863 		set_bit(port1, hub->power_bits);
864 	else
865 		clear_bit(port1, hub->power_bits);
866 	return 0;
867 }
868 
869 /**
870  * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
871  * @urb: an URB associated with the failed or incomplete split transaction
872  *
873  * High speed HCDs use this to tell the hub driver that some split control or
874  * bulk transaction failed in a way that requires clearing internal state of
875  * a transaction translator.  This is normally detected (and reported) from
876  * interrupt context.
877  *
878  * It may not be possible for that hub to handle additional full (or low)
879  * speed transactions until that state is fully cleared out.
880  *
881  * Return: 0 if successful. A negative error code otherwise.
882  */
usb_hub_clear_tt_buffer(struct urb * urb)883 int usb_hub_clear_tt_buffer(struct urb *urb)
884 {
885 	struct usb_device	*udev = urb->dev;
886 	int			pipe = urb->pipe;
887 	struct usb_tt		*tt = udev->tt;
888 	unsigned long		flags;
889 	struct usb_tt_clear	*clear;
890 
891 	/* we've got to cope with an arbitrary number of pending TT clears,
892 	 * since each TT has "at least two" buffers that can need it (and
893 	 * there can be many TTs per hub).  even if they're uncommon.
894 	 */
895 	clear = kmalloc(sizeof *clear, GFP_ATOMIC);
896 	if (clear == NULL) {
897 		dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
898 		/* FIXME recover somehow ... RESET_TT? */
899 		return -ENOMEM;
900 	}
901 
902 	/* info that CLEAR_TT_BUFFER needs */
903 	clear->tt = tt->multi ? udev->ttport : 1;
904 	clear->devinfo = usb_pipeendpoint (pipe);
905 	clear->devinfo |= ((u16)udev->devaddr) << 4;
906 	clear->devinfo |= usb_pipecontrol(pipe)
907 			? (USB_ENDPOINT_XFER_CONTROL << 11)
908 			: (USB_ENDPOINT_XFER_BULK << 11);
909 	if (usb_pipein(pipe))
910 		clear->devinfo |= 1 << 15;
911 
912 	/* info for completion callback */
913 	clear->hcd = bus_to_hcd(udev->bus);
914 	clear->ep = urb->ep;
915 
916 	/* tell keventd to clear state for this TT */
917 	spin_lock_irqsave(&tt->lock, flags);
918 	list_add_tail(&clear->clear_list, &tt->clear_list);
919 	schedule_work(&tt->clear_work);
920 	spin_unlock_irqrestore(&tt->lock, flags);
921 	return 0;
922 }
923 EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
924 
hub_power_on(struct usb_hub * hub,bool do_delay)925 static void hub_power_on(struct usb_hub *hub, bool do_delay)
926 {
927 	int port1;
928 
929 	/* Enable power on each port.  Some hubs have reserved values
930 	 * of LPSM (> 2) in their descriptors, even though they are
931 	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
932 	 * but only emulate it.  In all cases, the ports won't work
933 	 * unless we send these messages to the hub.
934 	 */
935 	if (hub_is_port_power_switchable(hub))
936 		dev_dbg(hub->intfdev, "enabling power on all ports\n");
937 	else
938 		dev_dbg(hub->intfdev, "trying to enable port power on "
939 				"non-switchable hub\n");
940 	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
941 		if (test_bit(port1, hub->power_bits))
942 			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
943 		else
944 			usb_clear_port_feature(hub->hdev, port1,
945 						USB_PORT_FEAT_POWER);
946 	if (do_delay)
947 		msleep(hub_power_on_good_delay(hub));
948 }
949 
hub_hub_status(struct usb_hub * hub,u16 * status,u16 * change)950 static int hub_hub_status(struct usb_hub *hub,
951 		u16 *status, u16 *change)
952 {
953 	int ret;
954 
955 	mutex_lock(&hub->status_mutex);
956 	ret = get_hub_status(hub->hdev, &hub->status->hub);
957 	if (ret < 0) {
958 		if (ret != -ENODEV)
959 			dev_err(hub->intfdev,
960 				"%s failed (err = %d)\n", __func__, ret);
961 	} else {
962 		*status = le16_to_cpu(hub->status->hub.wHubStatus);
963 		*change = le16_to_cpu(hub->status->hub.wHubChange);
964 		ret = 0;
965 	}
966 	mutex_unlock(&hub->status_mutex);
967 	return ret;
968 }
969 
hub_set_port_link_state(struct usb_hub * hub,int port1,unsigned int link_status)970 static int hub_set_port_link_state(struct usb_hub *hub, int port1,
971 			unsigned int link_status)
972 {
973 	return set_port_feature(hub->hdev,
974 			port1 | (link_status << 3),
975 			USB_PORT_FEAT_LINK_STATE);
976 }
977 
978 /*
979  * Disable a port and mark a logical connect-change event, so that some
980  * time later hub_wq will disconnect() any existing usb_device on the port
981  * and will re-enumerate if there actually is a device attached.
982  */
hub_port_logical_disconnect(struct usb_hub * hub,int port1)983 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
984 {
985 	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
986 	hub_port_disable(hub, port1, 1);
987 
988 	/* FIXME let caller ask to power down the port:
989 	 *  - some devices won't enumerate without a VBUS power cycle
990 	 *  - SRP saves power that way
991 	 *  - ... new call, TBD ...
992 	 * That's easy if this hub can switch power per-port, and
993 	 * hub_wq reactivates the port later (timer, SRP, etc).
994 	 * Powerdown must be optional, because of reset/DFU.
995 	 */
996 
997 	set_bit(port1, hub->change_bits);
998 	kick_hub_wq(hub);
999 }
1000 
1001 /**
1002  * usb_remove_device - disable a device's port on its parent hub
1003  * @udev: device to be disabled and removed
1004  * Context: @udev locked, must be able to sleep.
1005  *
1006  * After @udev's port has been disabled, hub_wq is notified and it will
1007  * see that the device has been disconnected.  When the device is
1008  * physically unplugged and something is plugged in, the events will
1009  * be received and processed normally.
1010  *
1011  * Return: 0 if successful. A negative error code otherwise.
1012  */
usb_remove_device(struct usb_device * udev)1013 int usb_remove_device(struct usb_device *udev)
1014 {
1015 	struct usb_hub *hub;
1016 	struct usb_interface *intf;
1017 	int ret;
1018 
1019 	if (!udev->parent)	/* Can't remove a root hub */
1020 		return -EINVAL;
1021 	hub = usb_hub_to_struct_hub(udev->parent);
1022 	intf = to_usb_interface(hub->intfdev);
1023 
1024 	ret = usb_autopm_get_interface(intf);
1025 	if (ret < 0)
1026 		return ret;
1027 
1028 	set_bit(udev->portnum, hub->removed_bits);
1029 	hub_port_logical_disconnect(hub, udev->portnum);
1030 	usb_autopm_put_interface(intf);
1031 	return 0;
1032 }
1033 
1034 enum hub_activation_type {
1035 	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1036 	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1037 };
1038 
1039 static void hub_init_func2(struct work_struct *ws);
1040 static void hub_init_func3(struct work_struct *ws);
1041 
hub_activate(struct usb_hub * hub,enum hub_activation_type type)1042 static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1043 {
1044 	struct usb_device *hdev = hub->hdev;
1045 	struct usb_hcd *hcd;
1046 	int ret;
1047 	int port1;
1048 	int status;
1049 	bool need_debounce_delay = false;
1050 	unsigned delay;
1051 
1052 	/* Continue a partial initialization */
1053 	if (type == HUB_INIT2 || type == HUB_INIT3) {
1054 		device_lock(&hdev->dev);
1055 
1056 		/* Was the hub disconnected while we were waiting? */
1057 		if (hub->disconnected)
1058 			goto disconnected;
1059 		if (type == HUB_INIT2)
1060 			goto init2;
1061 		goto init3;
1062 	}
1063 	kref_get(&hub->kref);
1064 
1065 	/* The superspeed hub except for root hub has to use Hub Depth
1066 	 * value as an offset into the route string to locate the bits
1067 	 * it uses to determine the downstream port number. So hub driver
1068 	 * should send a set hub depth request to superspeed hub after
1069 	 * the superspeed hub is set configuration in initialization or
1070 	 * reset procedure.
1071 	 *
1072 	 * After a resume, port power should still be on.
1073 	 * For any other type of activation, turn it on.
1074 	 */
1075 	if (type != HUB_RESUME) {
1076 		if (hdev->parent && hub_is_superspeed(hdev)) {
1077 			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1078 					HUB_SET_DEPTH, USB_RT_HUB,
1079 					hdev->level - 1, 0, NULL, 0,
1080 					USB_CTRL_SET_TIMEOUT);
1081 			if (ret < 0)
1082 				dev_err(hub->intfdev,
1083 						"set hub depth failed\n");
1084 		}
1085 
1086 		/* Speed up system boot by using a delayed_work for the
1087 		 * hub's initial power-up delays.  This is pretty awkward
1088 		 * and the implementation looks like a home-brewed sort of
1089 		 * setjmp/longjmp, but it saves at least 100 ms for each
1090 		 * root hub (assuming usbcore is compiled into the kernel
1091 		 * rather than as a module).  It adds up.
1092 		 *
1093 		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1094 		 * because for those activation types the ports have to be
1095 		 * operational when we return.  In theory this could be done
1096 		 * for HUB_POST_RESET, but it's easier not to.
1097 		 */
1098 		if (type == HUB_INIT) {
1099 			delay = hub_power_on_good_delay(hub);
1100 
1101 			hub_power_on(hub, false);
1102 			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1103 			queue_delayed_work(system_power_efficient_wq,
1104 					&hub->init_work,
1105 					msecs_to_jiffies(delay));
1106 
1107 			/* Suppress autosuspend until init is done */
1108 			usb_autopm_get_interface_no_resume(
1109 					to_usb_interface(hub->intfdev));
1110 			return;		/* Continues at init2: below */
1111 		} else if (type == HUB_RESET_RESUME) {
1112 			/* The internal host controller state for the hub device
1113 			 * may be gone after a host power loss on system resume.
1114 			 * Update the device's info so the HW knows it's a hub.
1115 			 */
1116 			hcd = bus_to_hcd(hdev->bus);
1117 			if (hcd->driver->update_hub_device) {
1118 				ret = hcd->driver->update_hub_device(hcd, hdev,
1119 						&hub->tt, GFP_NOIO);
1120 				if (ret < 0) {
1121 					dev_err(hub->intfdev,
1122 						"Host not accepting hub info update\n");
1123 					dev_err(hub->intfdev,
1124 						"LS/FS devices and hubs may not work under this hub\n");
1125 				}
1126 			}
1127 			hub_power_on(hub, true);
1128 		} else {
1129 			hub_power_on(hub, true);
1130 		}
1131 	/* Give some time on remote wakeup to let links to transit to U0 */
1132 	} else if (hub_is_superspeed(hub->hdev))
1133 		msleep(20);
1134 
1135  init2:
1136 
1137 	/*
1138 	 * Check each port and set hub->change_bits to let hub_wq know
1139 	 * which ports need attention.
1140 	 */
1141 	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1142 		struct usb_port *port_dev = hub->ports[port1 - 1];
1143 		struct usb_device *udev = port_dev->child;
1144 		u16 portstatus, portchange;
1145 
1146 		portstatus = portchange = 0;
1147 		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
1148 		if (status)
1149 			goto abort;
1150 
1151 		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1152 			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1153 					portstatus, portchange);
1154 
1155 		/*
1156 		 * After anything other than HUB_RESUME (i.e., initialization
1157 		 * or any sort of reset), every port should be disabled.
1158 		 * Unconnected ports should likewise be disabled (paranoia),
1159 		 * and so should ports for which we have no usb_device.
1160 		 */
1161 		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1162 				type != HUB_RESUME ||
1163 				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1164 				!udev ||
1165 				udev->state == USB_STATE_NOTATTACHED)) {
1166 			/*
1167 			 * USB3 protocol ports will automatically transition
1168 			 * to Enabled state when detect an USB3.0 device attach.
1169 			 * Do not disable USB3 protocol ports, just pretend
1170 			 * power was lost
1171 			 */
1172 			portstatus &= ~USB_PORT_STAT_ENABLE;
1173 			if (!hub_is_superspeed(hdev))
1174 				usb_clear_port_feature(hdev, port1,
1175 						   USB_PORT_FEAT_ENABLE);
1176 		}
1177 
1178 		/* Make sure a warm-reset request is handled by port_event */
1179 		if (type == HUB_RESUME &&
1180 		    hub_port_warm_reset_required(hub, port1, portstatus))
1181 			set_bit(port1, hub->event_bits);
1182 
1183 		/*
1184 		 * Add debounce if USB3 link is in polling/link training state.
1185 		 * Link will automatically transition to Enabled state after
1186 		 * link training completes.
1187 		 */
1188 		if (hub_is_superspeed(hdev) &&
1189 		    ((portstatus & USB_PORT_STAT_LINK_STATE) ==
1190 						USB_SS_PORT_LS_POLLING))
1191 			need_debounce_delay = true;
1192 
1193 		/* Clear status-change flags; we'll debounce later */
1194 		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1195 			need_debounce_delay = true;
1196 			usb_clear_port_feature(hub->hdev, port1,
1197 					USB_PORT_FEAT_C_CONNECTION);
1198 		}
1199 		if (portchange & USB_PORT_STAT_C_ENABLE) {
1200 			need_debounce_delay = true;
1201 			usb_clear_port_feature(hub->hdev, port1,
1202 					USB_PORT_FEAT_C_ENABLE);
1203 		}
1204 		if (portchange & USB_PORT_STAT_C_RESET) {
1205 			need_debounce_delay = true;
1206 			usb_clear_port_feature(hub->hdev, port1,
1207 					USB_PORT_FEAT_C_RESET);
1208 		}
1209 		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1210 				hub_is_superspeed(hub->hdev)) {
1211 			need_debounce_delay = true;
1212 			usb_clear_port_feature(hub->hdev, port1,
1213 					USB_PORT_FEAT_C_BH_PORT_RESET);
1214 		}
1215 		/* We can forget about a "removed" device when there's a
1216 		 * physical disconnect or the connect status changes.
1217 		 */
1218 		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1219 				(portchange & USB_PORT_STAT_C_CONNECTION))
1220 			clear_bit(port1, hub->removed_bits);
1221 
1222 		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1223 			/* Tell hub_wq to disconnect the device or
1224 			 * check for a new connection or over current condition.
1225 			 * Based on USB2.0 Spec Section 11.12.5,
1226 			 * C_PORT_OVER_CURRENT could be set while
1227 			 * PORT_OVER_CURRENT is not. So check for any of them.
1228 			 */
1229 			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1230 			    (portchange & USB_PORT_STAT_C_CONNECTION) ||
1231 			    (portstatus & USB_PORT_STAT_OVERCURRENT) ||
1232 			    (portchange & USB_PORT_STAT_C_OVERCURRENT))
1233 				set_bit(port1, hub->change_bits);
1234 
1235 		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1236 			bool port_resumed = (portstatus &
1237 					USB_PORT_STAT_LINK_STATE) ==
1238 				USB_SS_PORT_LS_U0;
1239 			/* The power session apparently survived the resume.
1240 			 * If there was an overcurrent or suspend change
1241 			 * (i.e., remote wakeup request), have hub_wq
1242 			 * take care of it.  Look at the port link state
1243 			 * for USB 3.0 hubs, since they don't have a suspend
1244 			 * change bit, and they don't set the port link change
1245 			 * bit on device-initiated resume.
1246 			 */
1247 			if (portchange || (hub_is_superspeed(hub->hdev) &&
1248 						port_resumed))
1249 				set_bit(port1, hub->event_bits);
1250 
1251 		} else if (udev->persist_enabled) {
1252 #ifdef CONFIG_PM
1253 			udev->reset_resume = 1;
1254 #endif
1255 			/* Don't set the change_bits when the device
1256 			 * was powered off.
1257 			 */
1258 			if (test_bit(port1, hub->power_bits))
1259 				set_bit(port1, hub->change_bits);
1260 
1261 		} else {
1262 			/* The power session is gone; tell hub_wq */
1263 			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1264 			set_bit(port1, hub->change_bits);
1265 		}
1266 	}
1267 
1268 	/* If no port-status-change flags were set, we don't need any
1269 	 * debouncing.  If flags were set we can try to debounce the
1270 	 * ports all at once right now, instead of letting hub_wq do them
1271 	 * one at a time later on.
1272 	 *
1273 	 * If any port-status changes do occur during this delay, hub_wq
1274 	 * will see them later and handle them normally.
1275 	 */
1276 	if (need_debounce_delay) {
1277 		delay = HUB_DEBOUNCE_STABLE;
1278 
1279 		/* Don't do a long sleep inside a workqueue routine */
1280 		if (type == HUB_INIT2) {
1281 			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1282 			queue_delayed_work(system_power_efficient_wq,
1283 					&hub->init_work,
1284 					msecs_to_jiffies(delay));
1285 			device_unlock(&hdev->dev);
1286 			return;		/* Continues at init3: below */
1287 		} else {
1288 			msleep(delay);
1289 		}
1290 	}
1291  init3:
1292 	hub->quiescing = 0;
1293 
1294 	status = usb_submit_urb(hub->urb, GFP_NOIO);
1295 	if (status < 0)
1296 		dev_err(hub->intfdev, "activate --> %d\n", status);
1297 	if (hub->has_indicators && blinkenlights)
1298 		queue_delayed_work(system_power_efficient_wq,
1299 				&hub->leds, LED_CYCLE_PERIOD);
1300 
1301 	/* Scan all ports that need attention */
1302 	kick_hub_wq(hub);
1303  abort:
1304 	if (type == HUB_INIT2 || type == HUB_INIT3) {
1305 		/* Allow autosuspend if it was suppressed */
1306  disconnected:
1307 		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1308 		device_unlock(&hdev->dev);
1309 	}
1310 
1311 	kref_put(&hub->kref, hub_release);
1312 }
1313 
1314 /* Implement the continuations for the delays above */
hub_init_func2(struct work_struct * ws)1315 static void hub_init_func2(struct work_struct *ws)
1316 {
1317 	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1318 
1319 	hub_activate(hub, HUB_INIT2);
1320 }
1321 
hub_init_func3(struct work_struct * ws)1322 static void hub_init_func3(struct work_struct *ws)
1323 {
1324 	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1325 
1326 	hub_activate(hub, HUB_INIT3);
1327 }
1328 
1329 enum hub_quiescing_type {
1330 	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1331 };
1332 
hub_quiesce(struct usb_hub * hub,enum hub_quiescing_type type)1333 static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1334 {
1335 	struct usb_device *hdev = hub->hdev;
1336 	unsigned long flags;
1337 	int i;
1338 
1339 	/* hub_wq and related activity won't re-trigger */
1340 	spin_lock_irqsave(&hub->irq_urb_lock, flags);
1341 	hub->quiescing = 1;
1342 	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
1343 
1344 	if (type != HUB_SUSPEND) {
1345 		/* Disconnect all the children */
1346 		for (i = 0; i < hdev->maxchild; ++i) {
1347 			if (hub->ports[i]->child)
1348 				usb_disconnect(&hub->ports[i]->child);
1349 		}
1350 	}
1351 
1352 	/* Stop hub_wq and related activity */
1353 	del_timer_sync(&hub->irq_urb_retry);
1354 	usb_kill_urb(hub->urb);
1355 	if (hub->has_indicators)
1356 		cancel_delayed_work_sync(&hub->leds);
1357 	if (hub->tt.hub)
1358 		flush_work(&hub->tt.clear_work);
1359 }
1360 
hub_pm_barrier_for_all_ports(struct usb_hub * hub)1361 static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1362 {
1363 	int i;
1364 
1365 	for (i = 0; i < hub->hdev->maxchild; ++i)
1366 		pm_runtime_barrier(&hub->ports[i]->dev);
1367 }
1368 
1369 /* caller has locked the hub device */
hub_pre_reset(struct usb_interface * intf)1370 static int hub_pre_reset(struct usb_interface *intf)
1371 {
1372 	struct usb_hub *hub = usb_get_intfdata(intf);
1373 
1374 	hub_quiesce(hub, HUB_PRE_RESET);
1375 	hub->in_reset = 1;
1376 	hub_pm_barrier_for_all_ports(hub);
1377 	return 0;
1378 }
1379 
1380 /* caller has locked the hub device */
hub_post_reset(struct usb_interface * intf)1381 static int hub_post_reset(struct usb_interface *intf)
1382 {
1383 	struct usb_hub *hub = usb_get_intfdata(intf);
1384 
1385 	hub->in_reset = 0;
1386 	hub_pm_barrier_for_all_ports(hub);
1387 	hub_activate(hub, HUB_POST_RESET);
1388 	return 0;
1389 }
1390 
hub_configure(struct usb_hub * hub,struct usb_endpoint_descriptor * endpoint)1391 static int hub_configure(struct usb_hub *hub,
1392 	struct usb_endpoint_descriptor *endpoint)
1393 {
1394 	struct usb_hcd *hcd;
1395 	struct usb_device *hdev = hub->hdev;
1396 	struct device *hub_dev = hub->intfdev;
1397 	u16 hubstatus, hubchange;
1398 	u16 wHubCharacteristics;
1399 	unsigned int pipe;
1400 	int maxp, ret, i;
1401 	char *message = "out of memory";
1402 	unsigned unit_load;
1403 	unsigned full_load;
1404 	unsigned maxchild;
1405 
1406 	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1407 	if (!hub->buffer) {
1408 		ret = -ENOMEM;
1409 		goto fail;
1410 	}
1411 
1412 	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1413 	if (!hub->status) {
1414 		ret = -ENOMEM;
1415 		goto fail;
1416 	}
1417 	mutex_init(&hub->status_mutex);
1418 
1419 	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1420 	if (!hub->descriptor) {
1421 		ret = -ENOMEM;
1422 		goto fail;
1423 	}
1424 
1425 	/* Request the entire hub descriptor.
1426 	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1427 	 * but a (non-SS) hub can/will return fewer bytes here.
1428 	 */
1429 	ret = get_hub_descriptor(hdev, hub->descriptor);
1430 	if (ret < 0) {
1431 		message = "can't read hub descriptor";
1432 		goto fail;
1433 	}
1434 
1435 	maxchild = USB_MAXCHILDREN;
1436 	if (hub_is_superspeed(hdev))
1437 		maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1438 
1439 	if (hub->descriptor->bNbrPorts > maxchild) {
1440 		message = "hub has too many ports!";
1441 		ret = -ENODEV;
1442 		goto fail;
1443 	} else if (hub->descriptor->bNbrPorts == 0) {
1444 		message = "hub doesn't have any ports!";
1445 		ret = -ENODEV;
1446 		goto fail;
1447 	}
1448 
1449 	/*
1450 	 * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
1451 	 * The resulting value will be used for SetIsochDelay() request.
1452 	 */
1453 	if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
1454 		u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
1455 
1456 		if (hdev->parent)
1457 			delay += hdev->parent->hub_delay;
1458 
1459 		delay += USB_TP_TRANSMISSION_DELAY;
1460 		hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
1461 	}
1462 
1463 	maxchild = hub->descriptor->bNbrPorts;
1464 	dev_info(hub_dev, "%d port%s detected\n", maxchild,
1465 			(maxchild == 1) ? "" : "s");
1466 
1467 	hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
1468 	if (!hub->ports) {
1469 		ret = -ENOMEM;
1470 		goto fail;
1471 	}
1472 
1473 	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1474 	if (hub_is_superspeed(hdev)) {
1475 		unit_load = 150;
1476 		full_load = 900;
1477 	} else {
1478 		unit_load = 100;
1479 		full_load = 500;
1480 	}
1481 
1482 	/* FIXME for USB 3.0, skip for now */
1483 	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1484 			!(hub_is_superspeed(hdev))) {
1485 		char	portstr[USB_MAXCHILDREN + 1];
1486 
1487 		for (i = 0; i < maxchild; i++)
1488 			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1489 				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1490 				? 'F' : 'R';
1491 		portstr[maxchild] = 0;
1492 		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1493 	} else
1494 		dev_dbg(hub_dev, "standalone hub\n");
1495 
1496 	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1497 	case HUB_CHAR_COMMON_LPSM:
1498 		dev_dbg(hub_dev, "ganged power switching\n");
1499 		break;
1500 	case HUB_CHAR_INDV_PORT_LPSM:
1501 		dev_dbg(hub_dev, "individual port power switching\n");
1502 		break;
1503 	case HUB_CHAR_NO_LPSM:
1504 	case HUB_CHAR_LPSM:
1505 		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1506 		break;
1507 	}
1508 
1509 	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1510 	case HUB_CHAR_COMMON_OCPM:
1511 		dev_dbg(hub_dev, "global over-current protection\n");
1512 		break;
1513 	case HUB_CHAR_INDV_PORT_OCPM:
1514 		dev_dbg(hub_dev, "individual port over-current protection\n");
1515 		break;
1516 	case HUB_CHAR_NO_OCPM:
1517 	case HUB_CHAR_OCPM:
1518 		dev_dbg(hub_dev, "no over-current protection\n");
1519 		break;
1520 	}
1521 
1522 	spin_lock_init(&hub->tt.lock);
1523 	INIT_LIST_HEAD(&hub->tt.clear_list);
1524 	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1525 	switch (hdev->descriptor.bDeviceProtocol) {
1526 	case USB_HUB_PR_FS:
1527 		break;
1528 	case USB_HUB_PR_HS_SINGLE_TT:
1529 		dev_dbg(hub_dev, "Single TT\n");
1530 		hub->tt.hub = hdev;
1531 		break;
1532 	case USB_HUB_PR_HS_MULTI_TT:
1533 		ret = usb_set_interface(hdev, 0, 1);
1534 		if (ret == 0) {
1535 			dev_dbg(hub_dev, "TT per port\n");
1536 			hub->tt.multi = 1;
1537 		} else
1538 			dev_err(hub_dev, "Using single TT (err %d)\n",
1539 				ret);
1540 		hub->tt.hub = hdev;
1541 		break;
1542 	case USB_HUB_PR_SS:
1543 		/* USB 3.0 hubs don't have a TT */
1544 		break;
1545 	default:
1546 		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1547 			hdev->descriptor.bDeviceProtocol);
1548 		break;
1549 	}
1550 
1551 	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1552 	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1553 	case HUB_TTTT_8_BITS:
1554 		if (hdev->descriptor.bDeviceProtocol != 0) {
1555 			hub->tt.think_time = 666;
1556 			dev_dbg(hub_dev, "TT requires at most %d "
1557 					"FS bit times (%d ns)\n",
1558 				8, hub->tt.think_time);
1559 		}
1560 		break;
1561 	case HUB_TTTT_16_BITS:
1562 		hub->tt.think_time = 666 * 2;
1563 		dev_dbg(hub_dev, "TT requires at most %d "
1564 				"FS bit times (%d ns)\n",
1565 			16, hub->tt.think_time);
1566 		break;
1567 	case HUB_TTTT_24_BITS:
1568 		hub->tt.think_time = 666 * 3;
1569 		dev_dbg(hub_dev, "TT requires at most %d "
1570 				"FS bit times (%d ns)\n",
1571 			24, hub->tt.think_time);
1572 		break;
1573 	case HUB_TTTT_32_BITS:
1574 		hub->tt.think_time = 666 * 4;
1575 		dev_dbg(hub_dev, "TT requires at most %d "
1576 				"FS bit times (%d ns)\n",
1577 			32, hub->tt.think_time);
1578 		break;
1579 	}
1580 
1581 	/* probe() zeroes hub->indicator[] */
1582 	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1583 		hub->has_indicators = 1;
1584 		dev_dbg(hub_dev, "Port indicators are supported\n");
1585 	}
1586 
1587 	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1588 		hub->descriptor->bPwrOn2PwrGood * 2);
1589 
1590 	/* power budgeting mostly matters with bus-powered hubs,
1591 	 * and battery-powered root hubs (may provide just 8 mA).
1592 	 */
1593 	ret = usb_get_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1594 	if (ret) {
1595 		message = "can't get hub status";
1596 		goto fail;
1597 	}
1598 	hcd = bus_to_hcd(hdev->bus);
1599 	if (hdev == hdev->bus->root_hub) {
1600 		if (hcd->power_budget > 0)
1601 			hdev->bus_mA = hcd->power_budget;
1602 		else
1603 			hdev->bus_mA = full_load * maxchild;
1604 		if (hdev->bus_mA >= full_load)
1605 			hub->mA_per_port = full_load;
1606 		else {
1607 			hub->mA_per_port = hdev->bus_mA;
1608 			hub->limited_power = 1;
1609 		}
1610 	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1611 		int remaining = hdev->bus_mA -
1612 			hub->descriptor->bHubContrCurrent;
1613 
1614 		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1615 			hub->descriptor->bHubContrCurrent);
1616 		hub->limited_power = 1;
1617 
1618 		if (remaining < maxchild * unit_load)
1619 			dev_warn(hub_dev,
1620 					"insufficient power available "
1621 					"to use all downstream ports\n");
1622 		hub->mA_per_port = unit_load;	/* 7.2.1 */
1623 
1624 	} else {	/* Self-powered external hub */
1625 		/* FIXME: What about battery-powered external hubs that
1626 		 * provide less current per port? */
1627 		hub->mA_per_port = full_load;
1628 	}
1629 	if (hub->mA_per_port < full_load)
1630 		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1631 				hub->mA_per_port);
1632 
1633 	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1634 	if (ret < 0) {
1635 		message = "can't get hub status";
1636 		goto fail;
1637 	}
1638 
1639 	/* local power status reports aren't always correct */
1640 	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1641 		dev_dbg(hub_dev, "local power source is %s\n",
1642 			(hubstatus & HUB_STATUS_LOCAL_POWER)
1643 			? "lost (inactive)" : "good");
1644 
1645 	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1646 		dev_dbg(hub_dev, "%sover-current condition exists\n",
1647 			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1648 
1649 	/* set up the interrupt endpoint
1650 	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1651 	 * bytes as USB2.0[11.12.3] says because some hubs are known
1652 	 * to send more data (and thus cause overflow). For root hubs,
1653 	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1654 	 * to be big enough for at least USB_MAXCHILDREN ports. */
1655 	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1656 	maxp = usb_maxpacket(hdev, pipe);
1657 
1658 	if (maxp > sizeof(*hub->buffer))
1659 		maxp = sizeof(*hub->buffer);
1660 
1661 	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1662 	if (!hub->urb) {
1663 		ret = -ENOMEM;
1664 		goto fail;
1665 	}
1666 
1667 	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1668 		hub, endpoint->bInterval);
1669 
1670 	/* maybe cycle the hub leds */
1671 	if (hub->has_indicators && blinkenlights)
1672 		hub->indicator[0] = INDICATOR_CYCLE;
1673 
1674 	mutex_lock(&usb_port_peer_mutex);
1675 	for (i = 0; i < maxchild; i++) {
1676 		ret = usb_hub_create_port_device(hub, i + 1);
1677 		if (ret < 0) {
1678 			dev_err(hub->intfdev,
1679 				"couldn't create port%d device.\n", i + 1);
1680 			break;
1681 		}
1682 	}
1683 	hdev->maxchild = i;
1684 	for (i = 0; i < hdev->maxchild; i++) {
1685 		struct usb_port *port_dev = hub->ports[i];
1686 
1687 		pm_runtime_put(&port_dev->dev);
1688 	}
1689 
1690 	mutex_unlock(&usb_port_peer_mutex);
1691 	if (ret < 0)
1692 		goto fail;
1693 
1694 	/* Update the HCD's internal representation of this hub before hub_wq
1695 	 * starts getting port status changes for devices under the hub.
1696 	 */
1697 	if (hcd->driver->update_hub_device) {
1698 		ret = hcd->driver->update_hub_device(hcd, hdev,
1699 				&hub->tt, GFP_KERNEL);
1700 		if (ret < 0) {
1701 			message = "can't update HCD hub info";
1702 			goto fail;
1703 		}
1704 	}
1705 
1706 	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1707 
1708 	hub_activate(hub, HUB_INIT);
1709 	return 0;
1710 
1711 fail:
1712 	dev_err(hub_dev, "config failed, %s (err %d)\n",
1713 			message, ret);
1714 	/* hub_disconnect() frees urb and descriptor */
1715 	return ret;
1716 }
1717 
hub_release(struct kref * kref)1718 static void hub_release(struct kref *kref)
1719 {
1720 	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1721 
1722 	usb_put_dev(hub->hdev);
1723 	usb_put_intf(to_usb_interface(hub->intfdev));
1724 	kfree(hub);
1725 }
1726 
1727 static unsigned highspeed_hubs;
1728 
hub_disconnect(struct usb_interface * intf)1729 static void hub_disconnect(struct usb_interface *intf)
1730 {
1731 	struct usb_hub *hub = usb_get_intfdata(intf);
1732 	struct usb_device *hdev = interface_to_usbdev(intf);
1733 	int port1;
1734 
1735 	/*
1736 	 * Stop adding new hub events. We do not want to block here and thus
1737 	 * will not try to remove any pending work item.
1738 	 */
1739 	hub->disconnected = 1;
1740 
1741 	/* Disconnect all children and quiesce the hub */
1742 	hub->error = 0;
1743 	hub_quiesce(hub, HUB_DISCONNECT);
1744 
1745 	mutex_lock(&usb_port_peer_mutex);
1746 
1747 	/* Avoid races with recursively_mark_NOTATTACHED() */
1748 	spin_lock_irq(&device_state_lock);
1749 	port1 = hdev->maxchild;
1750 	hdev->maxchild = 0;
1751 	usb_set_intfdata(intf, NULL);
1752 	spin_unlock_irq(&device_state_lock);
1753 
1754 	for (; port1 > 0; --port1)
1755 		usb_hub_remove_port_device(hub, port1);
1756 
1757 	mutex_unlock(&usb_port_peer_mutex);
1758 
1759 	if (hub->hdev->speed == USB_SPEED_HIGH)
1760 		highspeed_hubs--;
1761 
1762 	usb_free_urb(hub->urb);
1763 	kfree(hub->ports);
1764 	kfree(hub->descriptor);
1765 	kfree(hub->status);
1766 	kfree(hub->buffer);
1767 
1768 	pm_suspend_ignore_children(&intf->dev, false);
1769 
1770 	if (hub->quirk_disable_autosuspend)
1771 		usb_autopm_put_interface(intf);
1772 
1773 	onboard_hub_destroy_pdevs(&hub->onboard_hub_devs);
1774 
1775 	kref_put(&hub->kref, hub_release);
1776 }
1777 
hub_descriptor_is_sane(struct usb_host_interface * desc)1778 static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
1779 {
1780 	/* Some hubs have a subclass of 1, which AFAICT according to the */
1781 	/*  specs is not defined, but it works */
1782 	if (desc->desc.bInterfaceSubClass != 0 &&
1783 	    desc->desc.bInterfaceSubClass != 1)
1784 		return false;
1785 
1786 	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1787 	if (desc->desc.bNumEndpoints != 1)
1788 		return false;
1789 
1790 	/* If the first endpoint is not interrupt IN, we'd better punt! */
1791 	if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
1792 		return false;
1793 
1794         return true;
1795 }
1796 
hub_probe(struct usb_interface * intf,const struct usb_device_id * id)1797 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1798 {
1799 	struct usb_host_interface *desc;
1800 	struct usb_device *hdev;
1801 	struct usb_hub *hub;
1802 
1803 	desc = intf->cur_altsetting;
1804 	hdev = interface_to_usbdev(intf);
1805 
1806 	/*
1807 	 * Set default autosuspend delay as 0 to speedup bus suspend,
1808 	 * based on the below considerations:
1809 	 *
1810 	 * - Unlike other drivers, the hub driver does not rely on the
1811 	 *   autosuspend delay to provide enough time to handle a wakeup
1812 	 *   event, and the submitted status URB is just to check future
1813 	 *   change on hub downstream ports, so it is safe to do it.
1814 	 *
1815 	 * - The patch might cause one or more auto supend/resume for
1816 	 *   below very rare devices when they are plugged into hub
1817 	 *   first time:
1818 	 *
1819 	 *   	devices having trouble initializing, and disconnect
1820 	 *   	themselves from the bus and then reconnect a second
1821 	 *   	or so later
1822 	 *
1823 	 *   	devices just for downloading firmware, and disconnects
1824 	 *   	themselves after completing it
1825 	 *
1826 	 *   For these quite rare devices, their drivers may change the
1827 	 *   autosuspend delay of their parent hub in the probe() to one
1828 	 *   appropriate value to avoid the subtle problem if someone
1829 	 *   does care it.
1830 	 *
1831 	 * - The patch may cause one or more auto suspend/resume on
1832 	 *   hub during running 'lsusb', but it is probably too
1833 	 *   infrequent to worry about.
1834 	 *
1835 	 * - Change autosuspend delay of hub can avoid unnecessary auto
1836 	 *   suspend timer for hub, also may decrease power consumption
1837 	 *   of USB bus.
1838 	 *
1839 	 * - If user has indicated to prevent autosuspend by passing
1840 	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1841 	 */
1842 #ifdef CONFIG_PM
1843 	if (hdev->dev.power.autosuspend_delay >= 0)
1844 		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1845 #endif
1846 
1847 	/*
1848 	 * Hubs have proper suspend/resume support, except for root hubs
1849 	 * where the controller driver doesn't have bus_suspend and
1850 	 * bus_resume methods.
1851 	 */
1852 	if (hdev->parent) {		/* normal device */
1853 		usb_enable_autosuspend(hdev);
1854 	} else {			/* root hub */
1855 		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1856 
1857 		if (drv->bus_suspend && drv->bus_resume)
1858 			usb_enable_autosuspend(hdev);
1859 	}
1860 
1861 	if (hdev->level == MAX_TOPO_LEVEL) {
1862 		dev_err(&intf->dev,
1863 			"Unsupported bus topology: hub nested too deep\n");
1864 		return -E2BIG;
1865 	}
1866 
1867 #ifdef	CONFIG_USB_OTG_DISABLE_EXTERNAL_HUB
1868 	if (hdev->parent) {
1869 		dev_warn(&intf->dev, "ignoring external hub\n");
1870 		return -ENODEV;
1871 	}
1872 #endif
1873 
1874 	if (!hub_descriptor_is_sane(desc)) {
1875 		dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1876 		return -EIO;
1877 	}
1878 
1879 	/* We found a hub */
1880 	dev_info(&intf->dev, "USB hub found\n");
1881 
1882 	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1883 	if (!hub)
1884 		return -ENOMEM;
1885 
1886 	kref_init(&hub->kref);
1887 	hub->intfdev = &intf->dev;
1888 	hub->hdev = hdev;
1889 	INIT_DELAYED_WORK(&hub->leds, led_work);
1890 	INIT_DELAYED_WORK(&hub->init_work, NULL);
1891 	INIT_WORK(&hub->events, hub_event);
1892 	INIT_LIST_HEAD(&hub->onboard_hub_devs);
1893 	spin_lock_init(&hub->irq_urb_lock);
1894 	timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
1895 	usb_get_intf(intf);
1896 	usb_get_dev(hdev);
1897 
1898 	usb_set_intfdata(intf, hub);
1899 	intf->needs_remote_wakeup = 1;
1900 	pm_suspend_ignore_children(&intf->dev, true);
1901 
1902 	if (hdev->speed == USB_SPEED_HIGH)
1903 		highspeed_hubs++;
1904 
1905 	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1906 		hub->quirk_check_port_auto_suspend = 1;
1907 
1908 	if (id->driver_info & HUB_QUIRK_DISABLE_AUTOSUSPEND) {
1909 		hub->quirk_disable_autosuspend = 1;
1910 		usb_autopm_get_interface_no_resume(intf);
1911 	}
1912 
1913 	if ((id->driver_info & HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL) &&
1914 	    desc->endpoint[0].desc.bInterval > USB_REDUCE_FRAME_INTR_BINTERVAL) {
1915 		desc->endpoint[0].desc.bInterval =
1916 			USB_REDUCE_FRAME_INTR_BINTERVAL;
1917 		/* Tell the HCD about the interrupt ep's new bInterval */
1918 		usb_set_interface(hdev, 0, 0);
1919 	}
1920 
1921 	if (hub_configure(hub, &desc->endpoint[0].desc) >= 0) {
1922 		onboard_hub_create_pdevs(hdev, &hub->onboard_hub_devs);
1923 
1924 		return 0;
1925 	}
1926 
1927 	hub_disconnect(intf);
1928 	return -ENODEV;
1929 }
1930 
1931 static int
hub_ioctl(struct usb_interface * intf,unsigned int code,void * user_data)1932 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1933 {
1934 	struct usb_device *hdev = interface_to_usbdev(intf);
1935 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1936 
1937 	/* assert ifno == 0 (part of hub spec) */
1938 	switch (code) {
1939 	case USBDEVFS_HUB_PORTINFO: {
1940 		struct usbdevfs_hub_portinfo *info = user_data;
1941 		int i;
1942 
1943 		spin_lock_irq(&device_state_lock);
1944 		if (hdev->devnum <= 0)
1945 			info->nports = 0;
1946 		else {
1947 			info->nports = hdev->maxchild;
1948 			for (i = 0; i < info->nports; i++) {
1949 				if (hub->ports[i]->child == NULL)
1950 					info->port[i] = 0;
1951 				else
1952 					info->port[i] =
1953 						hub->ports[i]->child->devnum;
1954 			}
1955 		}
1956 		spin_unlock_irq(&device_state_lock);
1957 
1958 		return info->nports + 1;
1959 		}
1960 
1961 	default:
1962 		return -ENOSYS;
1963 	}
1964 }
1965 
1966 /*
1967  * Allow user programs to claim ports on a hub.  When a device is attached
1968  * to one of these "claimed" ports, the program will "own" the device.
1969  */
find_port_owner(struct usb_device * hdev,unsigned port1,struct usb_dev_state *** ppowner)1970 static int find_port_owner(struct usb_device *hdev, unsigned port1,
1971 		struct usb_dev_state ***ppowner)
1972 {
1973 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1974 
1975 	if (hdev->state == USB_STATE_NOTATTACHED)
1976 		return -ENODEV;
1977 	if (port1 == 0 || port1 > hdev->maxchild)
1978 		return -EINVAL;
1979 
1980 	/* Devices not managed by the hub driver
1981 	 * will always have maxchild equal to 0.
1982 	 */
1983 	*ppowner = &(hub->ports[port1 - 1]->port_owner);
1984 	return 0;
1985 }
1986 
1987 /* In the following three functions, the caller must hold hdev's lock */
usb_hub_claim_port(struct usb_device * hdev,unsigned port1,struct usb_dev_state * owner)1988 int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
1989 		       struct usb_dev_state *owner)
1990 {
1991 	int rc;
1992 	struct usb_dev_state **powner;
1993 
1994 	rc = find_port_owner(hdev, port1, &powner);
1995 	if (rc)
1996 		return rc;
1997 	if (*powner)
1998 		return -EBUSY;
1999 	*powner = owner;
2000 	return rc;
2001 }
2002 EXPORT_SYMBOL_GPL(usb_hub_claim_port);
2003 
usb_hub_release_port(struct usb_device * hdev,unsigned port1,struct usb_dev_state * owner)2004 int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
2005 			 struct usb_dev_state *owner)
2006 {
2007 	int rc;
2008 	struct usb_dev_state **powner;
2009 
2010 	rc = find_port_owner(hdev, port1, &powner);
2011 	if (rc)
2012 		return rc;
2013 	if (*powner != owner)
2014 		return -ENOENT;
2015 	*powner = NULL;
2016 	return rc;
2017 }
2018 EXPORT_SYMBOL_GPL(usb_hub_release_port);
2019 
usb_hub_release_all_ports(struct usb_device * hdev,struct usb_dev_state * owner)2020 void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
2021 {
2022 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
2023 	int n;
2024 
2025 	for (n = 0; n < hdev->maxchild; n++) {
2026 		if (hub->ports[n]->port_owner == owner)
2027 			hub->ports[n]->port_owner = NULL;
2028 	}
2029 
2030 }
2031 
2032 /* The caller must hold udev's lock */
usb_device_is_owned(struct usb_device * udev)2033 bool usb_device_is_owned(struct usb_device *udev)
2034 {
2035 	struct usb_hub *hub;
2036 
2037 	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
2038 		return false;
2039 	hub = usb_hub_to_struct_hub(udev->parent);
2040 	return !!hub->ports[udev->portnum - 1]->port_owner;
2041 }
2042 
update_port_device_state(struct usb_device * udev)2043 static void update_port_device_state(struct usb_device *udev)
2044 {
2045 	struct usb_hub *hub;
2046 	struct usb_port *port_dev;
2047 
2048 	if (udev->parent) {
2049 		hub = usb_hub_to_struct_hub(udev->parent);
2050 
2051 		/*
2052 		 * The Link Layer Validation System Driver (lvstest)
2053 		 * has a test step to unbind the hub before running the
2054 		 * rest of the procedure. This triggers hub_disconnect
2055 		 * which will set the hub's maxchild to 0, further
2056 		 * resulting in usb_hub_to_struct_hub returning NULL.
2057 		 */
2058 		if (hub) {
2059 			port_dev = hub->ports[udev->portnum - 1];
2060 			WRITE_ONCE(port_dev->state, udev->state);
2061 			sysfs_notify_dirent(port_dev->state_kn);
2062 		}
2063 	}
2064 }
2065 
recursively_mark_NOTATTACHED(struct usb_device * udev)2066 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
2067 {
2068 	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2069 	int i;
2070 
2071 	for (i = 0; i < udev->maxchild; ++i) {
2072 		if (hub->ports[i]->child)
2073 			recursively_mark_NOTATTACHED(hub->ports[i]->child);
2074 	}
2075 	if (udev->state == USB_STATE_SUSPENDED)
2076 		udev->active_duration -= jiffies;
2077 	udev->state = USB_STATE_NOTATTACHED;
2078 	update_port_device_state(udev);
2079 }
2080 
2081 /**
2082  * usb_set_device_state - change a device's current state (usbcore, hcds)
2083  * @udev: pointer to device whose state should be changed
2084  * @new_state: new state value to be stored
2085  *
2086  * udev->state is _not_ fully protected by the device lock.  Although
2087  * most transitions are made only while holding the lock, the state can
2088  * can change to USB_STATE_NOTATTACHED at almost any time.  This
2089  * is so that devices can be marked as disconnected as soon as possible,
2090  * without having to wait for any semaphores to be released.  As a result,
2091  * all changes to any device's state must be protected by the
2092  * device_state_lock spinlock.
2093  *
2094  * Once a device has been added to the device tree, all changes to its state
2095  * should be made using this routine.  The state should _not_ be set directly.
2096  *
2097  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2098  * Otherwise udev->state is set to new_state, and if new_state is
2099  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2100  * to USB_STATE_NOTATTACHED.
2101  */
usb_set_device_state(struct usb_device * udev,enum usb_device_state new_state)2102 void usb_set_device_state(struct usb_device *udev,
2103 		enum usb_device_state new_state)
2104 {
2105 	unsigned long flags;
2106 	int wakeup = -1;
2107 
2108 	spin_lock_irqsave(&device_state_lock, flags);
2109 	if (udev->state == USB_STATE_NOTATTACHED)
2110 		;	/* do nothing */
2111 	else if (new_state != USB_STATE_NOTATTACHED) {
2112 
2113 		/* root hub wakeup capabilities are managed out-of-band
2114 		 * and may involve silicon errata ... ignore them here.
2115 		 */
2116 		if (udev->parent) {
2117 			if (udev->state == USB_STATE_SUSPENDED
2118 					|| new_state == USB_STATE_SUSPENDED)
2119 				;	/* No change to wakeup settings */
2120 			else if (new_state == USB_STATE_CONFIGURED)
2121 				wakeup = (udev->quirks &
2122 					USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2123 					udev->actconfig->desc.bmAttributes &
2124 					USB_CONFIG_ATT_WAKEUP;
2125 			else
2126 				wakeup = 0;
2127 		}
2128 		if (udev->state == USB_STATE_SUSPENDED &&
2129 			new_state != USB_STATE_SUSPENDED)
2130 			udev->active_duration -= jiffies;
2131 		else if (new_state == USB_STATE_SUSPENDED &&
2132 				udev->state != USB_STATE_SUSPENDED)
2133 			udev->active_duration += jiffies;
2134 		udev->state = new_state;
2135 		update_port_device_state(udev);
2136 	} else
2137 		recursively_mark_NOTATTACHED(udev);
2138 	spin_unlock_irqrestore(&device_state_lock, flags);
2139 	if (wakeup >= 0)
2140 		device_set_wakeup_capable(&udev->dev, wakeup);
2141 }
2142 EXPORT_SYMBOL_GPL(usb_set_device_state);
2143 
2144 /*
2145  * Choose a device number.
2146  *
2147  * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2148  * USB-2.0 buses they are also used as device addresses, however on
2149  * USB-3.0 buses the address is assigned by the controller hardware
2150  * and it usually is not the same as the device number.
2151  *
2152  * Devices connected under xHCI are not as simple.  The host controller
2153  * supports virtualization, so the hardware assigns device addresses and
2154  * the HCD must setup data structures before issuing a set address
2155  * command to the hardware.
2156  */
choose_devnum(struct usb_device * udev)2157 static void choose_devnum(struct usb_device *udev)
2158 {
2159 	int		devnum;
2160 	struct usb_bus	*bus = udev->bus;
2161 
2162 	/* be safe when more hub events are proceed in parallel */
2163 	mutex_lock(&bus->devnum_next_mutex);
2164 
2165 	/* Try to allocate the next devnum beginning at bus->devnum_next. */
2166 	devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
2167 			bus->devnum_next);
2168 	if (devnum >= 128)
2169 		devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
2170 	bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
2171 	if (devnum < 128) {
2172 		set_bit(devnum, bus->devmap.devicemap);
2173 		udev->devnum = devnum;
2174 	}
2175 	mutex_unlock(&bus->devnum_next_mutex);
2176 }
2177 
release_devnum(struct usb_device * udev)2178 static void release_devnum(struct usb_device *udev)
2179 {
2180 	if (udev->devnum > 0) {
2181 		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
2182 		udev->devnum = -1;
2183 	}
2184 }
2185 
update_devnum(struct usb_device * udev,int devnum)2186 static void update_devnum(struct usb_device *udev, int devnum)
2187 {
2188 	udev->devnum = devnum;
2189 	if (!udev->devaddr)
2190 		udev->devaddr = (u8)devnum;
2191 }
2192 
hub_free_dev(struct usb_device * udev)2193 static void hub_free_dev(struct usb_device *udev)
2194 {
2195 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2196 
2197 	/* Root hubs aren't real devices, so don't free HCD resources */
2198 	if (hcd->driver->free_dev && udev->parent)
2199 		hcd->driver->free_dev(hcd, udev);
2200 }
2201 
hub_disconnect_children(struct usb_device * udev)2202 static void hub_disconnect_children(struct usb_device *udev)
2203 {
2204 	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2205 	int i;
2206 
2207 	/* Free up all the children before we remove this device */
2208 	for (i = 0; i < udev->maxchild; i++) {
2209 		if (hub->ports[i]->child)
2210 			usb_disconnect(&hub->ports[i]->child);
2211 	}
2212 }
2213 
2214 /**
2215  * usb_disconnect - disconnect a device (usbcore-internal)
2216  * @pdev: pointer to device being disconnected
2217  *
2218  * Context: task context, might sleep
2219  *
2220  * Something got disconnected. Get rid of it and all of its children.
2221  *
2222  * If *pdev is a normal device then the parent hub must already be locked.
2223  * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2224  * which protects the set of root hubs as well as the list of buses.
2225  *
2226  * Only hub drivers (including virtual root hub drivers for host
2227  * controllers) should ever call this.
2228  *
2229  * This call is synchronous, and may not be used in an interrupt context.
2230  */
usb_disconnect(struct usb_device ** pdev)2231 void usb_disconnect(struct usb_device **pdev)
2232 {
2233 	struct usb_port *port_dev = NULL;
2234 	struct usb_device *udev = *pdev;
2235 	struct usb_hub *hub = NULL;
2236 	int port1 = 1;
2237 
2238 	/* mark the device as inactive, so any further urb submissions for
2239 	 * this device (and any of its children) will fail immediately.
2240 	 * this quiesces everything except pending urbs.
2241 	 */
2242 	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2243 	dev_info(&udev->dev, "USB disconnect, device number %d\n",
2244 			udev->devnum);
2245 
2246 	/*
2247 	 * Ensure that the pm runtime code knows that the USB device
2248 	 * is in the process of being disconnected.
2249 	 */
2250 	pm_runtime_barrier(&udev->dev);
2251 
2252 	usb_lock_device(udev);
2253 
2254 	hub_disconnect_children(udev);
2255 
2256 	/* deallocate hcd/hardware state ... nuking all pending urbs and
2257 	 * cleaning up all state associated with the current configuration
2258 	 * so that the hardware is now fully quiesced.
2259 	 */
2260 	dev_dbg(&udev->dev, "unregistering device\n");
2261 	usb_disable_device(udev, 0);
2262 	usb_hcd_synchronize_unlinks(udev);
2263 
2264 	if (udev->parent) {
2265 		port1 = udev->portnum;
2266 		hub = usb_hub_to_struct_hub(udev->parent);
2267 		port_dev = hub->ports[port1 - 1];
2268 
2269 		sysfs_remove_link(&udev->dev.kobj, "port");
2270 		sysfs_remove_link(&port_dev->dev.kobj, "device");
2271 
2272 		/*
2273 		 * As usb_port_runtime_resume() de-references udev, make
2274 		 * sure no resumes occur during removal
2275 		 */
2276 		if (!test_and_set_bit(port1, hub->child_usage_bits))
2277 			pm_runtime_get_sync(&port_dev->dev);
2278 	}
2279 
2280 	usb_remove_ep_devs(&udev->ep0);
2281 	usb_unlock_device(udev);
2282 
2283 	/* Unregister the device.  The device driver is responsible
2284 	 * for de-configuring the device and invoking the remove-device
2285 	 * notifier chain (used by usbfs and possibly others).
2286 	 */
2287 	device_del(&udev->dev);
2288 
2289 	/* Free the device number and delete the parent's children[]
2290 	 * (or root_hub) pointer.
2291 	 */
2292 	release_devnum(udev);
2293 
2294 	/* Avoid races with recursively_mark_NOTATTACHED() */
2295 	spin_lock_irq(&device_state_lock);
2296 	*pdev = NULL;
2297 	spin_unlock_irq(&device_state_lock);
2298 
2299 	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2300 		pm_runtime_put(&port_dev->dev);
2301 
2302 	hub_free_dev(udev);
2303 
2304 	put_device(&udev->dev);
2305 }
2306 
2307 #ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
show_string(struct usb_device * udev,char * id,char * string)2308 static void show_string(struct usb_device *udev, char *id, char *string)
2309 {
2310 	if (!string)
2311 		return;
2312 	dev_info(&udev->dev, "%s: %s\n", id, string);
2313 }
2314 
announce_device(struct usb_device * udev)2315 static void announce_device(struct usb_device *udev)
2316 {
2317 	u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
2318 
2319 	dev_info(&udev->dev,
2320 		"New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
2321 		le16_to_cpu(udev->descriptor.idVendor),
2322 		le16_to_cpu(udev->descriptor.idProduct),
2323 		bcdDevice >> 8, bcdDevice & 0xff);
2324 	dev_info(&udev->dev,
2325 		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2326 		udev->descriptor.iManufacturer,
2327 		udev->descriptor.iProduct,
2328 		udev->descriptor.iSerialNumber);
2329 	show_string(udev, "Product", udev->product);
2330 	show_string(udev, "Manufacturer", udev->manufacturer);
2331 	show_string(udev, "SerialNumber", udev->serial);
2332 }
2333 #else
announce_device(struct usb_device * udev)2334 static inline void announce_device(struct usb_device *udev) { }
2335 #endif
2336 
2337 
2338 /**
2339  * usb_enumerate_device_otg - FIXME (usbcore-internal)
2340  * @udev: newly addressed device (in ADDRESS state)
2341  *
2342  * Finish enumeration for On-The-Go devices
2343  *
2344  * Return: 0 if successful. A negative error code otherwise.
2345  */
usb_enumerate_device_otg(struct usb_device * udev)2346 static int usb_enumerate_device_otg(struct usb_device *udev)
2347 {
2348 	int err = 0;
2349 
2350 #ifdef	CONFIG_USB_OTG
2351 	/*
2352 	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2353 	 * to wake us after we've powered off VBUS; and HNP, switching roles
2354 	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
2355 	 */
2356 	if (!udev->bus->is_b_host
2357 			&& udev->config
2358 			&& udev->parent == udev->bus->root_hub) {
2359 		struct usb_otg_descriptor	*desc = NULL;
2360 		struct usb_bus			*bus = udev->bus;
2361 		unsigned			port1 = udev->portnum;
2362 
2363 		/* descriptor may appear anywhere in config */
2364 		err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2365 				le16_to_cpu(udev->config[0].desc.wTotalLength),
2366 				USB_DT_OTG, (void **) &desc, sizeof(*desc));
2367 		if (err || !(desc->bmAttributes & USB_OTG_HNP))
2368 			return 0;
2369 
2370 		dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2371 					(port1 == bus->otg_port) ? "" : "non-");
2372 
2373 		/* enable HNP before suspend, it's simpler */
2374 		if (port1 == bus->otg_port) {
2375 			bus->b_hnp_enable = 1;
2376 			err = usb_control_msg(udev,
2377 				usb_sndctrlpipe(udev, 0),
2378 				USB_REQ_SET_FEATURE, 0,
2379 				USB_DEVICE_B_HNP_ENABLE,
2380 				0, NULL, 0,
2381 				USB_CTRL_SET_TIMEOUT);
2382 			if (err < 0) {
2383 				/*
2384 				 * OTG MESSAGE: report errors here,
2385 				 * customize to match your product.
2386 				 */
2387 				dev_err(&udev->dev, "can't set HNP mode: %d\n",
2388 									err);
2389 				bus->b_hnp_enable = 0;
2390 			}
2391 		} else if (desc->bLength == sizeof
2392 				(struct usb_otg_descriptor)) {
2393 			/*
2394 			 * We are operating on a legacy OTP device
2395 			 * These should be told that they are operating
2396 			 * on the wrong port if we have another port that does
2397 			 * support HNP
2398 			 */
2399 			if (bus->otg_port != 0) {
2400 				/* Set a_alt_hnp_support for legacy otg device */
2401 				err = usb_control_msg(udev,
2402 					usb_sndctrlpipe(udev, 0),
2403 					USB_REQ_SET_FEATURE, 0,
2404 					USB_DEVICE_A_ALT_HNP_SUPPORT,
2405 					0, NULL, 0,
2406 					USB_CTRL_SET_TIMEOUT);
2407 				if (err < 0)
2408 					dev_err(&udev->dev,
2409 						"set a_alt_hnp_support failed: %d\n",
2410 						err);
2411 			}
2412 		}
2413 	}
2414 #endif
2415 	return err;
2416 }
2417 
2418 
2419 /**
2420  * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2421  * @udev: newly addressed device (in ADDRESS state)
2422  *
2423  * This is only called by usb_new_device() -- all comments that apply there
2424  * apply here wrt to environment.
2425  *
2426  * If the device is WUSB and not authorized, we don't attempt to read
2427  * the string descriptors, as they will be errored out by the device
2428  * until it has been authorized.
2429  *
2430  * Return: 0 if successful. A negative error code otherwise.
2431  */
usb_enumerate_device(struct usb_device * udev)2432 static int usb_enumerate_device(struct usb_device *udev)
2433 {
2434 	int err;
2435 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2436 
2437 	if (udev->config == NULL) {
2438 		err = usb_get_configuration(udev);
2439 		if (err < 0) {
2440 			if (err != -ENODEV)
2441 				dev_err(&udev->dev, "can't read configurations, error %d\n",
2442 						err);
2443 			return err;
2444 		}
2445 	}
2446 
2447 	/* read the standard strings and cache them if present */
2448 	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2449 	udev->manufacturer = usb_cache_string(udev,
2450 					      udev->descriptor.iManufacturer);
2451 	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2452 
2453 	err = usb_enumerate_device_otg(udev);
2454 	if (err < 0)
2455 		return err;
2456 
2457 	if (IS_ENABLED(CONFIG_USB_OTG_PRODUCTLIST) && hcd->tpl_support &&
2458 		!is_targeted(udev)) {
2459 		/* Maybe it can talk to us, though we can't talk to it.
2460 		 * (Includes HNP test device.)
2461 		 */
2462 		if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2463 			|| udev->bus->is_b_host)) {
2464 			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2465 			if (err < 0)
2466 				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2467 		}
2468 		return -ENOTSUPP;
2469 	}
2470 
2471 	usb_detect_interface_quirks(udev);
2472 
2473 	return 0;
2474 }
2475 
set_usb_port_removable(struct usb_device * udev)2476 static void set_usb_port_removable(struct usb_device *udev)
2477 {
2478 	struct usb_device *hdev = udev->parent;
2479 	struct usb_hub *hub;
2480 	u8 port = udev->portnum;
2481 	u16 wHubCharacteristics;
2482 	bool removable = true;
2483 
2484 	dev_set_removable(&udev->dev, DEVICE_REMOVABLE_UNKNOWN);
2485 
2486 	if (!hdev)
2487 		return;
2488 
2489 	hub = usb_hub_to_struct_hub(udev->parent);
2490 
2491 	/*
2492 	 * If the platform firmware has provided information about a port,
2493 	 * use that to determine whether it's removable.
2494 	 */
2495 	switch (hub->ports[udev->portnum - 1]->connect_type) {
2496 	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2497 		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2498 		return;
2499 	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2500 	case USB_PORT_NOT_USED:
2501 		dev_set_removable(&udev->dev, DEVICE_FIXED);
2502 		return;
2503 	default:
2504 		break;
2505 	}
2506 
2507 	/*
2508 	 * Otherwise, check whether the hub knows whether a port is removable
2509 	 * or not
2510 	 */
2511 	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2512 
2513 	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2514 		return;
2515 
2516 	if (hub_is_superspeed(hdev)) {
2517 		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2518 				& (1 << port))
2519 			removable = false;
2520 	} else {
2521 		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2522 			removable = false;
2523 	}
2524 
2525 	if (removable)
2526 		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2527 	else
2528 		dev_set_removable(&udev->dev, DEVICE_FIXED);
2529 
2530 }
2531 
2532 /**
2533  * usb_new_device - perform initial device setup (usbcore-internal)
2534  * @udev: newly addressed device (in ADDRESS state)
2535  *
2536  * This is called with devices which have been detected but not fully
2537  * enumerated.  The device descriptor is available, but not descriptors
2538  * for any device configuration.  The caller must have locked either
2539  * the parent hub (if udev is a normal device) or else the
2540  * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2541  * udev has already been installed, but udev is not yet visible through
2542  * sysfs or other filesystem code.
2543  *
2544  * This call is synchronous, and may not be used in an interrupt context.
2545  *
2546  * Only the hub driver or root-hub registrar should ever call this.
2547  *
2548  * Return: Whether the device is configured properly or not. Zero if the
2549  * interface was registered with the driver core; else a negative errno
2550  * value.
2551  *
2552  */
usb_new_device(struct usb_device * udev)2553 int usb_new_device(struct usb_device *udev)
2554 {
2555 	int err;
2556 
2557 	if (udev->parent) {
2558 		/* Initialize non-root-hub device wakeup to disabled;
2559 		 * device (un)configuration controls wakeup capable
2560 		 * sysfs power/wakeup controls wakeup enabled/disabled
2561 		 */
2562 		device_init_wakeup(&udev->dev, 0);
2563 	}
2564 
2565 	/* Tell the runtime-PM framework the device is active */
2566 	pm_runtime_set_active(&udev->dev);
2567 	pm_runtime_get_noresume(&udev->dev);
2568 	pm_runtime_use_autosuspend(&udev->dev);
2569 	pm_runtime_enable(&udev->dev);
2570 
2571 	/* By default, forbid autosuspend for all devices.  It will be
2572 	 * allowed for hubs during binding.
2573 	 */
2574 	usb_disable_autosuspend(udev);
2575 
2576 	err = usb_enumerate_device(udev);	/* Read descriptors */
2577 	if (err < 0)
2578 		goto fail;
2579 	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2580 			udev->devnum, udev->bus->busnum,
2581 			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2582 	/* export the usbdev device-node for libusb */
2583 	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2584 			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2585 
2586 	/* Tell the world! */
2587 	announce_device(udev);
2588 
2589 	if (udev->serial)
2590 		add_device_randomness(udev->serial, strlen(udev->serial));
2591 	if (udev->product)
2592 		add_device_randomness(udev->product, strlen(udev->product));
2593 	if (udev->manufacturer)
2594 		add_device_randomness(udev->manufacturer,
2595 				      strlen(udev->manufacturer));
2596 
2597 	device_enable_async_suspend(&udev->dev);
2598 
2599 	/* check whether the hub or firmware marks this port as non-removable */
2600 	set_usb_port_removable(udev);
2601 
2602 	/* Register the device.  The device driver is responsible
2603 	 * for configuring the device and invoking the add-device
2604 	 * notifier chain (used by usbfs and possibly others).
2605 	 */
2606 	err = device_add(&udev->dev);
2607 	if (err) {
2608 		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2609 		goto fail;
2610 	}
2611 
2612 	/* Create link files between child device and usb port device. */
2613 	if (udev->parent) {
2614 		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2615 		int port1 = udev->portnum;
2616 		struct usb_port	*port_dev = hub->ports[port1 - 1];
2617 
2618 		err = sysfs_create_link(&udev->dev.kobj,
2619 				&port_dev->dev.kobj, "port");
2620 		if (err)
2621 			goto fail;
2622 
2623 		err = sysfs_create_link(&port_dev->dev.kobj,
2624 				&udev->dev.kobj, "device");
2625 		if (err) {
2626 			sysfs_remove_link(&udev->dev.kobj, "port");
2627 			goto fail;
2628 		}
2629 
2630 		if (!test_and_set_bit(port1, hub->child_usage_bits))
2631 			pm_runtime_get_sync(&port_dev->dev);
2632 	}
2633 
2634 	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2635 	usb_mark_last_busy(udev);
2636 	pm_runtime_put_sync_autosuspend(&udev->dev);
2637 	return err;
2638 
2639 fail:
2640 	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2641 	pm_runtime_disable(&udev->dev);
2642 	pm_runtime_set_suspended(&udev->dev);
2643 	return err;
2644 }
2645 
2646 
2647 /**
2648  * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2649  * @usb_dev: USB device
2650  *
2651  * Move the USB device to a very basic state where interfaces are disabled
2652  * and the device is in fact unconfigured and unusable.
2653  *
2654  * We share a lock (that we have) with device_del(), so we need to
2655  * defer its call.
2656  *
2657  * Return: 0.
2658  */
usb_deauthorize_device(struct usb_device * usb_dev)2659 int usb_deauthorize_device(struct usb_device *usb_dev)
2660 {
2661 	usb_lock_device(usb_dev);
2662 	if (usb_dev->authorized == 0)
2663 		goto out_unauthorized;
2664 
2665 	usb_dev->authorized = 0;
2666 	usb_set_configuration(usb_dev, -1);
2667 
2668 out_unauthorized:
2669 	usb_unlock_device(usb_dev);
2670 	return 0;
2671 }
2672 
2673 
usb_authorize_device(struct usb_device * usb_dev)2674 int usb_authorize_device(struct usb_device *usb_dev)
2675 {
2676 	int result = 0, c;
2677 
2678 	usb_lock_device(usb_dev);
2679 	if (usb_dev->authorized == 1)
2680 		goto out_authorized;
2681 
2682 	result = usb_autoresume_device(usb_dev);
2683 	if (result < 0) {
2684 		dev_err(&usb_dev->dev,
2685 			"can't autoresume for authorization: %d\n", result);
2686 		goto error_autoresume;
2687 	}
2688 
2689 	usb_dev->authorized = 1;
2690 	/* Choose and set the configuration.  This registers the interfaces
2691 	 * with the driver core and lets interface drivers bind to them.
2692 	 */
2693 	c = usb_choose_configuration(usb_dev);
2694 	if (c >= 0) {
2695 		result = usb_set_configuration(usb_dev, c);
2696 		if (result) {
2697 			dev_err(&usb_dev->dev,
2698 				"can't set config #%d, error %d\n", c, result);
2699 			/* This need not be fatal.  The user can try to
2700 			 * set other configurations. */
2701 		}
2702 	}
2703 	dev_info(&usb_dev->dev, "authorized to connect\n");
2704 
2705 	usb_autosuspend_device(usb_dev);
2706 error_autoresume:
2707 out_authorized:
2708 	usb_unlock_device(usb_dev);	/* complements locktree */
2709 	return result;
2710 }
2711 
2712 /**
2713  * get_port_ssp_rate - Match the extended port status to SSP rate
2714  * @hdev: The hub device
2715  * @ext_portstatus: extended port status
2716  *
2717  * Match the extended port status speed id to the SuperSpeed Plus sublink speed
2718  * capability attributes. Base on the number of connected lanes and speed,
2719  * return the corresponding enum usb_ssp_rate.
2720  */
get_port_ssp_rate(struct usb_device * hdev,u32 ext_portstatus)2721 static enum usb_ssp_rate get_port_ssp_rate(struct usb_device *hdev,
2722 					   u32 ext_portstatus)
2723 {
2724 	struct usb_ssp_cap_descriptor *ssp_cap;
2725 	u32 attr;
2726 	u8 speed_id;
2727 	u8 ssac;
2728 	u8 lanes;
2729 	int i;
2730 
2731 	if (!hdev->bos)
2732 		goto out;
2733 
2734 	ssp_cap = hdev->bos->ssp_cap;
2735 	if (!ssp_cap)
2736 		goto out;
2737 
2738 	speed_id = ext_portstatus & USB_EXT_PORT_STAT_RX_SPEED_ID;
2739 	lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2740 
2741 	ssac = le32_to_cpu(ssp_cap->bmAttributes) &
2742 		USB_SSP_SUBLINK_SPEED_ATTRIBS;
2743 
2744 	for (i = 0; i <= ssac; i++) {
2745 		u8 ssid;
2746 
2747 		attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2748 		ssid = FIELD_GET(USB_SSP_SUBLINK_SPEED_SSID, attr);
2749 		if (speed_id == ssid) {
2750 			u16 mantissa;
2751 			u8 lse;
2752 			u8 type;
2753 
2754 			/*
2755 			 * Note: currently asymmetric lane types are only
2756 			 * applicable for SSIC operate in SuperSpeed protocol
2757 			 */
2758 			type = FIELD_GET(USB_SSP_SUBLINK_SPEED_ST, attr);
2759 			if (type == USB_SSP_SUBLINK_SPEED_ST_ASYM_RX ||
2760 			    type == USB_SSP_SUBLINK_SPEED_ST_ASYM_TX)
2761 				goto out;
2762 
2763 			if (FIELD_GET(USB_SSP_SUBLINK_SPEED_LP, attr) !=
2764 			    USB_SSP_SUBLINK_SPEED_LP_SSP)
2765 				goto out;
2766 
2767 			lse = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSE, attr);
2768 			mantissa = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSM, attr);
2769 
2770 			/* Convert to Gbps */
2771 			for (; lse < USB_SSP_SUBLINK_SPEED_LSE_GBPS; lse++)
2772 				mantissa /= 1000;
2773 
2774 			if (mantissa >= 10 && lanes == 1)
2775 				return USB_SSP_GEN_2x1;
2776 
2777 			if (mantissa >= 10 && lanes == 2)
2778 				return USB_SSP_GEN_2x2;
2779 
2780 			if (mantissa >= 5 && lanes == 2)
2781 				return USB_SSP_GEN_1x2;
2782 
2783 			goto out;
2784 		}
2785 	}
2786 
2787 out:
2788 	return USB_SSP_GEN_UNKNOWN;
2789 }
2790 
2791 #ifdef CONFIG_USB_FEW_INIT_RETRIES
2792 #define PORT_RESET_TRIES	2
2793 #define SET_ADDRESS_TRIES	1
2794 #define GET_DESCRIPTOR_TRIES	1
2795 #define GET_MAXPACKET0_TRIES	1
2796 #define PORT_INIT_TRIES		4
2797 
2798 #else
2799 #define PORT_RESET_TRIES	5
2800 #define SET_ADDRESS_TRIES	2
2801 #define GET_DESCRIPTOR_TRIES	2
2802 #define GET_MAXPACKET0_TRIES	3
2803 #define PORT_INIT_TRIES		4
2804 #endif	/* CONFIG_USB_FEW_INIT_RETRIES */
2805 
2806 #define DETECT_DISCONNECT_TRIES 5
2807 
2808 #define HUB_ROOT_RESET_TIME	60	/* times are in msec */
2809 #define HUB_SHORT_RESET_TIME	10
2810 #define HUB_BH_RESET_TIME	50
2811 #define HUB_LONG_RESET_TIME	200
2812 #define HUB_RESET_TIMEOUT	800
2813 
use_new_scheme(struct usb_device * udev,int retry,struct usb_port * port_dev)2814 static bool use_new_scheme(struct usb_device *udev, int retry,
2815 			   struct usb_port *port_dev)
2816 {
2817 	int old_scheme_first_port =
2818 		(port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME) ||
2819 		old_scheme_first;
2820 
2821 	/*
2822 	 * "New scheme" enumeration causes an extra state transition to be
2823 	 * exposed to an xhci host and causes USB3 devices to receive control
2824 	 * commands in the default state.  This has been seen to cause
2825 	 * enumeration failures, so disable this enumeration scheme for USB3
2826 	 * devices.
2827 	 */
2828 	if (udev->speed >= USB_SPEED_SUPER)
2829 		return false;
2830 
2831 	/*
2832 	 * If use_both_schemes is set, use the first scheme (whichever
2833 	 * it is) for the larger half of the retries, then use the other
2834 	 * scheme.  Otherwise, use the first scheme for all the retries.
2835 	 */
2836 	if (use_both_schemes && retry >= (PORT_INIT_TRIES + 1) / 2)
2837 		return old_scheme_first_port;	/* Second half */
2838 	return !old_scheme_first_port;		/* First half or all */
2839 }
2840 
2841 /* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2842  * Port warm reset is required to recover
2843  */
hub_port_warm_reset_required(struct usb_hub * hub,int port1,u16 portstatus)2844 static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2845 		u16 portstatus)
2846 {
2847 	u16 link_state;
2848 
2849 	if (!hub_is_superspeed(hub->hdev))
2850 		return false;
2851 
2852 	if (test_bit(port1, hub->warm_reset_bits))
2853 		return true;
2854 
2855 	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2856 	return link_state == USB_SS_PORT_LS_SS_INACTIVE
2857 		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2858 }
2859 
hub_port_wait_reset(struct usb_hub * hub,int port1,struct usb_device * udev,unsigned int delay,bool warm)2860 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2861 			struct usb_device *udev, unsigned int delay, bool warm)
2862 {
2863 	int delay_time, ret;
2864 	u16 portstatus;
2865 	u16 portchange;
2866 	u32 ext_portstatus = 0;
2867 
2868 	for (delay_time = 0;
2869 			delay_time < HUB_RESET_TIMEOUT;
2870 			delay_time += delay) {
2871 		/* wait to give the device a chance to reset */
2872 		msleep(delay);
2873 
2874 		/* read and decode port status */
2875 		if (hub_is_superspeedplus(hub->hdev))
2876 			ret = hub_ext_port_status(hub, port1,
2877 						  HUB_EXT_PORT_STATUS,
2878 						  &portstatus, &portchange,
2879 						  &ext_portstatus);
2880 		else
2881 			ret = usb_hub_port_status(hub, port1, &portstatus,
2882 					      &portchange);
2883 		if (ret < 0)
2884 			return ret;
2885 
2886 		/*
2887 		 * The port state is unknown until the reset completes.
2888 		 *
2889 		 * On top of that, some chips may require additional time
2890 		 * to re-establish a connection after the reset is complete,
2891 		 * so also wait for the connection to be re-established.
2892 		 */
2893 		if (!(portstatus & USB_PORT_STAT_RESET) &&
2894 		    (portstatus & USB_PORT_STAT_CONNECTION))
2895 			break;
2896 
2897 		/* switch to the long delay after two short delay failures */
2898 		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2899 			delay = HUB_LONG_RESET_TIME;
2900 
2901 		dev_dbg(&hub->ports[port1 - 1]->dev,
2902 				"not %sreset yet, waiting %dms\n",
2903 				warm ? "warm " : "", delay);
2904 	}
2905 
2906 	if ((portstatus & USB_PORT_STAT_RESET))
2907 		return -EBUSY;
2908 
2909 	if (hub_port_warm_reset_required(hub, port1, portstatus))
2910 		return -ENOTCONN;
2911 
2912 	/* Device went away? */
2913 	if (!(portstatus & USB_PORT_STAT_CONNECTION))
2914 		return -ENOTCONN;
2915 
2916 	/* Retry if connect change is set but status is still connected.
2917 	 * A USB 3.0 connection may bounce if multiple warm resets were issued,
2918 	 * but the device may have successfully re-connected. Ignore it.
2919 	 */
2920 	if (!hub_is_superspeed(hub->hdev) &&
2921 	    (portchange & USB_PORT_STAT_C_CONNECTION)) {
2922 		usb_clear_port_feature(hub->hdev, port1,
2923 				       USB_PORT_FEAT_C_CONNECTION);
2924 		return -EAGAIN;
2925 	}
2926 
2927 	if (!(portstatus & USB_PORT_STAT_ENABLE))
2928 		return -EBUSY;
2929 
2930 	if (!udev)
2931 		return 0;
2932 
2933 	if (hub_is_superspeedplus(hub->hdev)) {
2934 		/* extended portstatus Rx and Tx lane count are zero based */
2935 		udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2936 		udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
2937 		udev->ssp_rate = get_port_ssp_rate(hub->hdev, ext_portstatus);
2938 	} else {
2939 		udev->rx_lanes = 1;
2940 		udev->tx_lanes = 1;
2941 		udev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2942 	}
2943 	if (udev->ssp_rate != USB_SSP_GEN_UNKNOWN)
2944 		udev->speed = USB_SPEED_SUPER_PLUS;
2945 	else if (hub_is_superspeed(hub->hdev))
2946 		udev->speed = USB_SPEED_SUPER;
2947 	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2948 		udev->speed = USB_SPEED_HIGH;
2949 	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2950 		udev->speed = USB_SPEED_LOW;
2951 	else
2952 		udev->speed = USB_SPEED_FULL;
2953 	return 0;
2954 }
2955 
2956 /* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
hub_port_reset(struct usb_hub * hub,int port1,struct usb_device * udev,unsigned int delay,bool warm)2957 static int hub_port_reset(struct usb_hub *hub, int port1,
2958 			struct usb_device *udev, unsigned int delay, bool warm)
2959 {
2960 	int i, status;
2961 	u16 portchange, portstatus;
2962 	struct usb_port *port_dev = hub->ports[port1 - 1];
2963 	int reset_recovery_time;
2964 
2965 	if (!hub_is_superspeed(hub->hdev)) {
2966 		if (warm) {
2967 			dev_err(hub->intfdev, "only USB3 hub support "
2968 						"warm reset\n");
2969 			return -EINVAL;
2970 		}
2971 		/* Block EHCI CF initialization during the port reset.
2972 		 * Some companion controllers don't like it when they mix.
2973 		 */
2974 		down_read(&ehci_cf_port_reset_rwsem);
2975 	} else if (!warm) {
2976 		/*
2977 		 * If the caller hasn't explicitly requested a warm reset,
2978 		 * double check and see if one is needed.
2979 		 */
2980 		if (usb_hub_port_status(hub, port1, &portstatus,
2981 					&portchange) == 0)
2982 			if (hub_port_warm_reset_required(hub, port1,
2983 							portstatus))
2984 				warm = true;
2985 	}
2986 	clear_bit(port1, hub->warm_reset_bits);
2987 
2988 	/* Reset the port */
2989 	for (i = 0; i < PORT_RESET_TRIES; i++) {
2990 		status = set_port_feature(hub->hdev, port1, (warm ?
2991 					USB_PORT_FEAT_BH_PORT_RESET :
2992 					USB_PORT_FEAT_RESET));
2993 		if (status == -ENODEV) {
2994 			;	/* The hub is gone */
2995 		} else if (status) {
2996 			dev_err(&port_dev->dev,
2997 					"cannot %sreset (err = %d)\n",
2998 					warm ? "warm " : "", status);
2999 		} else {
3000 			status = hub_port_wait_reset(hub, port1, udev, delay,
3001 								warm);
3002 			if (status && status != -ENOTCONN && status != -ENODEV)
3003 				dev_dbg(hub->intfdev,
3004 						"port_wait_reset: err = %d\n",
3005 						status);
3006 		}
3007 
3008 		/*
3009 		 * Check for disconnect or reset, and bail out after several
3010 		 * reset attempts to avoid warm reset loop.
3011 		 */
3012 		if (status == 0 || status == -ENOTCONN || status == -ENODEV ||
3013 		    (status == -EBUSY && i == PORT_RESET_TRIES - 1)) {
3014 			usb_clear_port_feature(hub->hdev, port1,
3015 					USB_PORT_FEAT_C_RESET);
3016 
3017 			if (!hub_is_superspeed(hub->hdev))
3018 				goto done;
3019 
3020 			usb_clear_port_feature(hub->hdev, port1,
3021 					USB_PORT_FEAT_C_BH_PORT_RESET);
3022 			usb_clear_port_feature(hub->hdev, port1,
3023 					USB_PORT_FEAT_C_PORT_LINK_STATE);
3024 
3025 			if (udev)
3026 				usb_clear_port_feature(hub->hdev, port1,
3027 					USB_PORT_FEAT_C_CONNECTION);
3028 
3029 			/*
3030 			 * If a USB 3.0 device migrates from reset to an error
3031 			 * state, re-issue the warm reset.
3032 			 */
3033 			if (usb_hub_port_status(hub, port1,
3034 					&portstatus, &portchange) < 0)
3035 				goto done;
3036 
3037 			if (!hub_port_warm_reset_required(hub, port1,
3038 					portstatus))
3039 				goto done;
3040 
3041 			/*
3042 			 * If the port is in SS.Inactive or Compliance Mode, the
3043 			 * hot or warm reset failed.  Try another warm reset.
3044 			 */
3045 			if (!warm) {
3046 				dev_dbg(&port_dev->dev,
3047 						"hot reset failed, warm reset\n");
3048 				warm = true;
3049 			}
3050 		}
3051 
3052 		dev_dbg(&port_dev->dev,
3053 				"not enabled, trying %sreset again...\n",
3054 				warm ? "warm " : "");
3055 		delay = HUB_LONG_RESET_TIME;
3056 	}
3057 
3058 	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
3059 
3060 done:
3061 	if (status == 0) {
3062 		if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
3063 			usleep_range(10000, 12000);
3064 		else {
3065 			/* TRSTRCY = 10 ms; plus some extra */
3066 			reset_recovery_time = 10 + 40;
3067 
3068 			/* Hub needs extra delay after resetting its port. */
3069 			if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
3070 				reset_recovery_time += 100;
3071 
3072 			msleep(reset_recovery_time);
3073 		}
3074 
3075 		if (udev) {
3076 			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3077 
3078 			update_devnum(udev, 0);
3079 			/* The xHC may think the device is already reset,
3080 			 * so ignore the status.
3081 			 */
3082 			if (hcd->driver->reset_device)
3083 				hcd->driver->reset_device(hcd, udev);
3084 
3085 			usb_set_device_state(udev, USB_STATE_DEFAULT);
3086 		}
3087 	} else {
3088 		if (udev)
3089 			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
3090 	}
3091 
3092 	if (!hub_is_superspeed(hub->hdev))
3093 		up_read(&ehci_cf_port_reset_rwsem);
3094 
3095 	return status;
3096 }
3097 
3098 /*
3099  * hub_port_stop_enumerate - stop USB enumeration or ignore port events
3100  * @hub: target hub
3101  * @port1: port num of the port
3102  * @retries: port retries number of hub_port_init()
3103  *
3104  * Return:
3105  *    true: ignore port actions/events or give up connection attempts.
3106  *    false: keep original behavior.
3107  *
3108  * This function will be based on retries to check whether the port which is
3109  * marked with early_stop attribute would stop enumeration or ignore events.
3110  *
3111  * Note:
3112  * This function didn't change anything if early_stop is not set, and it will
3113  * prevent all connection attempts when early_stop is set and the attempts of
3114  * the port are more than 1.
3115  */
hub_port_stop_enumerate(struct usb_hub * hub,int port1,int retries)3116 static bool hub_port_stop_enumerate(struct usb_hub *hub, int port1, int retries)
3117 {
3118 	struct usb_port *port_dev = hub->ports[port1 - 1];
3119 
3120 	if (port_dev->early_stop) {
3121 		if (port_dev->ignore_event)
3122 			return true;
3123 
3124 		/*
3125 		 * We want unsuccessful attempts to fail quickly.
3126 		 * Since some devices may need one failure during
3127 		 * port initialization, we allow two tries but no
3128 		 * more.
3129 		 */
3130 		if (retries < 2)
3131 			return false;
3132 
3133 		port_dev->ignore_event = 1;
3134 	} else
3135 		port_dev->ignore_event = 0;
3136 
3137 	return port_dev->ignore_event;
3138 }
3139 
3140 /* Check if a port is power on */
usb_port_is_power_on(struct usb_hub * hub,unsigned int portstatus)3141 int usb_port_is_power_on(struct usb_hub *hub, unsigned int portstatus)
3142 {
3143 	int ret = 0;
3144 
3145 	if (hub_is_superspeed(hub->hdev)) {
3146 		if (portstatus & USB_SS_PORT_STAT_POWER)
3147 			ret = 1;
3148 	} else {
3149 		if (portstatus & USB_PORT_STAT_POWER)
3150 			ret = 1;
3151 	}
3152 
3153 	return ret;
3154 }
3155 
usb_lock_port(struct usb_port * port_dev)3156 static void usb_lock_port(struct usb_port *port_dev)
3157 		__acquires(&port_dev->status_lock)
3158 {
3159 	mutex_lock(&port_dev->status_lock);
3160 	__acquire(&port_dev->status_lock);
3161 }
3162 
usb_unlock_port(struct usb_port * port_dev)3163 static void usb_unlock_port(struct usb_port *port_dev)
3164 		__releases(&port_dev->status_lock)
3165 {
3166 	mutex_unlock(&port_dev->status_lock);
3167 	__release(&port_dev->status_lock);
3168 }
3169 
3170 #ifdef	CONFIG_PM
3171 
3172 /* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
port_is_suspended(struct usb_hub * hub,unsigned portstatus)3173 static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
3174 {
3175 	int ret = 0;
3176 
3177 	if (hub_is_superspeed(hub->hdev)) {
3178 		if ((portstatus & USB_PORT_STAT_LINK_STATE)
3179 				== USB_SS_PORT_LS_U3)
3180 			ret = 1;
3181 	} else {
3182 		if (portstatus & USB_PORT_STAT_SUSPEND)
3183 			ret = 1;
3184 	}
3185 
3186 	return ret;
3187 }
3188 
3189 /* Determine whether the device on a port is ready for a normal resume,
3190  * is ready for a reset-resume, or should be disconnected.
3191  */
check_port_resume_type(struct usb_device * udev,struct usb_hub * hub,int port1,int status,u16 portchange,u16 portstatus)3192 static int check_port_resume_type(struct usb_device *udev,
3193 		struct usb_hub *hub, int port1,
3194 		int status, u16 portchange, u16 portstatus)
3195 {
3196 	struct usb_port *port_dev = hub->ports[port1 - 1];
3197 	int retries = 3;
3198 
3199  retry:
3200 	/* Is a warm reset needed to recover the connection? */
3201 	if (status == 0 && udev->reset_resume
3202 		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
3203 		/* pass */;
3204 	}
3205 	/* Is the device still present? */
3206 	else if (status || port_is_suspended(hub, portstatus) ||
3207 			!usb_port_is_power_on(hub, portstatus)) {
3208 		if (status >= 0)
3209 			status = -ENODEV;
3210 	} else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
3211 		if (retries--) {
3212 			usleep_range(200, 300);
3213 			status = usb_hub_port_status(hub, port1, &portstatus,
3214 							     &portchange);
3215 			goto retry;
3216 		}
3217 		status = -ENODEV;
3218 	}
3219 
3220 	/* Can't do a normal resume if the port isn't enabled,
3221 	 * so try a reset-resume instead.
3222 	 */
3223 	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3224 		if (udev->persist_enabled)
3225 			udev->reset_resume = 1;
3226 		else
3227 			status = -ENODEV;
3228 	}
3229 
3230 	if (status) {
3231 		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3232 				portchange, portstatus, status);
3233 	} else if (udev->reset_resume) {
3234 
3235 		/* Late port handoff can set status-change bits */
3236 		if (portchange & USB_PORT_STAT_C_CONNECTION)
3237 			usb_clear_port_feature(hub->hdev, port1,
3238 					USB_PORT_FEAT_C_CONNECTION);
3239 		if (portchange & USB_PORT_STAT_C_ENABLE)
3240 			usb_clear_port_feature(hub->hdev, port1,
3241 					USB_PORT_FEAT_C_ENABLE);
3242 
3243 		/*
3244 		 * Whatever made this reset-resume necessary may have
3245 		 * turned on the port1 bit in hub->change_bits.  But after
3246 		 * a successful reset-resume we want the bit to be clear;
3247 		 * if it was on it would indicate that something happened
3248 		 * following the reset-resume.
3249 		 */
3250 		clear_bit(port1, hub->change_bits);
3251 	}
3252 
3253 	return status;
3254 }
3255 
usb_disable_ltm(struct usb_device * udev)3256 int usb_disable_ltm(struct usb_device *udev)
3257 {
3258 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3259 
3260 	/* Check if the roothub and device supports LTM. */
3261 	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3262 			!usb_device_supports_ltm(udev))
3263 		return 0;
3264 
3265 	/* Clear Feature LTM Enable can only be sent if the device is
3266 	 * configured.
3267 	 */
3268 	if (!udev->actconfig)
3269 		return 0;
3270 
3271 	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3272 			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3273 			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3274 			USB_CTRL_SET_TIMEOUT);
3275 }
3276 EXPORT_SYMBOL_GPL(usb_disable_ltm);
3277 
usb_enable_ltm(struct usb_device * udev)3278 void usb_enable_ltm(struct usb_device *udev)
3279 {
3280 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3281 
3282 	/* Check if the roothub and device supports LTM. */
3283 	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3284 			!usb_device_supports_ltm(udev))
3285 		return;
3286 
3287 	/* Set Feature LTM Enable can only be sent if the device is
3288 	 * configured.
3289 	 */
3290 	if (!udev->actconfig)
3291 		return;
3292 
3293 	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3294 			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3295 			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3296 			USB_CTRL_SET_TIMEOUT);
3297 }
3298 EXPORT_SYMBOL_GPL(usb_enable_ltm);
3299 
3300 /*
3301  * usb_enable_remote_wakeup - enable remote wakeup for a device
3302  * @udev: target device
3303  *
3304  * For USB-2 devices: Set the device's remote wakeup feature.
3305  *
3306  * For USB-3 devices: Assume there's only one function on the device and
3307  * enable remote wake for the first interface.  FIXME if the interface
3308  * association descriptor shows there's more than one function.
3309  */
usb_enable_remote_wakeup(struct usb_device * udev)3310 static int usb_enable_remote_wakeup(struct usb_device *udev)
3311 {
3312 	if (udev->speed < USB_SPEED_SUPER)
3313 		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3314 				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3315 				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3316 				USB_CTRL_SET_TIMEOUT);
3317 	else
3318 		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3319 				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3320 				USB_INTRF_FUNC_SUSPEND,
3321 				USB_INTRF_FUNC_SUSPEND_RW |
3322 					USB_INTRF_FUNC_SUSPEND_LP,
3323 				NULL, 0, USB_CTRL_SET_TIMEOUT);
3324 }
3325 
3326 /*
3327  * usb_disable_remote_wakeup - disable remote wakeup for a device
3328  * @udev: target device
3329  *
3330  * For USB-2 devices: Clear the device's remote wakeup feature.
3331  *
3332  * For USB-3 devices: Assume there's only one function on the device and
3333  * disable remote wake for the first interface.  FIXME if the interface
3334  * association descriptor shows there's more than one function.
3335  */
usb_disable_remote_wakeup(struct usb_device * udev)3336 static int usb_disable_remote_wakeup(struct usb_device *udev)
3337 {
3338 	if (udev->speed < USB_SPEED_SUPER)
3339 		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3340 				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3341 				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3342 				USB_CTRL_SET_TIMEOUT);
3343 	else
3344 		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3345 				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3346 				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
3347 				USB_CTRL_SET_TIMEOUT);
3348 }
3349 
3350 /* Count of wakeup-enabled devices at or below udev */
usb_wakeup_enabled_descendants(struct usb_device * udev)3351 unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
3352 {
3353 	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3354 
3355 	return udev->do_remote_wakeup +
3356 			(hub ? hub->wakeup_enabled_descendants : 0);
3357 }
3358 EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
3359 
3360 /*
3361  * usb_port_suspend - suspend a usb device's upstream port
3362  * @udev: device that's no longer in active use, not a root hub
3363  * Context: must be able to sleep; device not locked; pm locks held
3364  *
3365  * Suspends a USB device that isn't in active use, conserving power.
3366  * Devices may wake out of a suspend, if anything important happens,
3367  * using the remote wakeup mechanism.  They may also be taken out of
3368  * suspend by the host, using usb_port_resume().  It's also routine
3369  * to disconnect devices while they are suspended.
3370  *
3371  * This only affects the USB hardware for a device; its interfaces
3372  * (and, for hubs, child devices) must already have been suspended.
3373  *
3374  * Selective port suspend reduces power; most suspended devices draw
3375  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3376  * All devices below the suspended port are also suspended.
3377  *
3378  * Devices leave suspend state when the host wakes them up.  Some devices
3379  * also support "remote wakeup", where the device can activate the USB
3380  * tree above them to deliver data, such as a keypress or packet.  In
3381  * some cases, this wakes the USB host.
3382  *
3383  * Suspending OTG devices may trigger HNP, if that's been enabled
3384  * between a pair of dual-role devices.  That will change roles, such
3385  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3386  *
3387  * Devices on USB hub ports have only one "suspend" state, corresponding
3388  * to ACPI D2, "may cause the device to lose some context".
3389  * State transitions include:
3390  *
3391  *   - suspend, resume ... when the VBUS power link stays live
3392  *   - suspend, disconnect ... VBUS lost
3393  *
3394  * Once VBUS drop breaks the circuit, the port it's using has to go through
3395  * normal re-enumeration procedures, starting with enabling VBUS power.
3396  * Other than re-initializing the hub (plug/unplug, except for root hubs),
3397  * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3398  * timer, no SRP, no requests through sysfs.
3399  *
3400  * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3401  * suspended until their bus goes into global suspend (i.e., the root
3402  * hub is suspended).  Nevertheless, we change @udev->state to
3403  * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3404  * upstream port setting is stored in @udev->port_is_suspended.
3405  *
3406  * Returns 0 on success, else negative errno.
3407  */
usb_port_suspend(struct usb_device * udev,pm_message_t msg)3408 int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3409 {
3410 	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3411 	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3412 	int		port1 = udev->portnum;
3413 	int		status;
3414 	bool		really_suspend = true;
3415 
3416 	usb_lock_port(port_dev);
3417 
3418 	/* enable remote wakeup when appropriate; this lets the device
3419 	 * wake up the upstream hub (including maybe the root hub).
3420 	 *
3421 	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3422 	 * we don't explicitly enable it here.
3423 	 */
3424 	if (udev->do_remote_wakeup) {
3425 		status = usb_enable_remote_wakeup(udev);
3426 		if (status) {
3427 			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3428 					status);
3429 			/* bail if autosuspend is requested */
3430 			if (PMSG_IS_AUTO(msg))
3431 				goto err_wakeup;
3432 		}
3433 	}
3434 
3435 	/* disable USB2 hardware LPM */
3436 	usb_disable_usb2_hardware_lpm(udev);
3437 
3438 	if (usb_disable_ltm(udev)) {
3439 		dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
3440 		status = -ENOMEM;
3441 		if (PMSG_IS_AUTO(msg))
3442 			goto err_ltm;
3443 	}
3444 
3445 	/* see 7.1.7.6 */
3446 	if (hub_is_superspeed(hub->hdev))
3447 		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3448 
3449 	/*
3450 	 * For system suspend, we do not need to enable the suspend feature
3451 	 * on individual USB-2 ports.  The devices will automatically go
3452 	 * into suspend a few ms after the root hub stops sending packets.
3453 	 * The USB 2.0 spec calls this "global suspend".
3454 	 *
3455 	 * However, many USB hubs have a bug: They don't relay wakeup requests
3456 	 * from a downstream port if the port's suspend feature isn't on.
3457 	 * Therefore we will turn on the suspend feature if udev or any of its
3458 	 * descendants is enabled for remote wakeup.
3459 	 */
3460 	else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
3461 		status = set_port_feature(hub->hdev, port1,
3462 				USB_PORT_FEAT_SUSPEND);
3463 	else {
3464 		really_suspend = false;
3465 		status = 0;
3466 	}
3467 	if (status) {
3468 		/* Check if the port has been suspended for the timeout case
3469 		 * to prevent the suspended port from incorrect handling.
3470 		 */
3471 		if (status == -ETIMEDOUT) {
3472 			int ret;
3473 			u16 portstatus, portchange;
3474 
3475 			portstatus = portchange = 0;
3476 			ret = usb_hub_port_status(hub, port1, &portstatus,
3477 					&portchange);
3478 
3479 			dev_dbg(&port_dev->dev,
3480 				"suspend timeout, status %04x\n", portstatus);
3481 
3482 			if (ret == 0 && port_is_suspended(hub, portstatus)) {
3483 				status = 0;
3484 				goto suspend_done;
3485 			}
3486 		}
3487 
3488 		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3489 
3490 		/* Try to enable USB3 LTM again */
3491 		usb_enable_ltm(udev);
3492  err_ltm:
3493 		/* Try to enable USB2 hardware LPM again */
3494 		usb_enable_usb2_hardware_lpm(udev);
3495 
3496 		if (udev->do_remote_wakeup)
3497 			(void) usb_disable_remote_wakeup(udev);
3498  err_wakeup:
3499 
3500 		/* System sleep transitions should never fail */
3501 		if (!PMSG_IS_AUTO(msg))
3502 			status = 0;
3503 	} else {
3504  suspend_done:
3505 		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3506 				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
3507 				udev->do_remote_wakeup);
3508 		if (really_suspend) {
3509 			udev->port_is_suspended = 1;
3510 
3511 			/* device has up to 10 msec to fully suspend */
3512 			msleep(10);
3513 		}
3514 		usb_set_device_state(udev, USB_STATE_SUSPENDED);
3515 	}
3516 
3517 	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3518 			&& test_and_clear_bit(port1, hub->child_usage_bits))
3519 		pm_runtime_put_sync(&port_dev->dev);
3520 
3521 	usb_mark_last_busy(hub->hdev);
3522 
3523 	usb_unlock_port(port_dev);
3524 	return status;
3525 }
3526 
3527 /*
3528  * If the USB "suspend" state is in use (rather than "global suspend"),
3529  * many devices will be individually taken out of suspend state using
3530  * special "resume" signaling.  This routine kicks in shortly after
3531  * hardware resume signaling is finished, either because of selective
3532  * resume (by host) or remote wakeup (by device) ... now see what changed
3533  * in the tree that's rooted at this device.
3534  *
3535  * If @udev->reset_resume is set then the device is reset before the
3536  * status check is done.
3537  */
finish_port_resume(struct usb_device * udev)3538 static int finish_port_resume(struct usb_device *udev)
3539 {
3540 	int	status = 0;
3541 	u16	devstatus = 0;
3542 
3543 	/* caller owns the udev device lock */
3544 	dev_dbg(&udev->dev, "%s\n",
3545 		udev->reset_resume ? "finish reset-resume" : "finish resume");
3546 
3547 	/* usb ch9 identifies four variants of SUSPENDED, based on what
3548 	 * state the device resumes to.  Linux currently won't see the
3549 	 * first two on the host side; they'd be inside hub_port_init()
3550 	 * during many timeouts, but hub_wq can't suspend until later.
3551 	 */
3552 	usb_set_device_state(udev, udev->actconfig
3553 			? USB_STATE_CONFIGURED
3554 			: USB_STATE_ADDRESS);
3555 
3556 	/* 10.5.4.5 says not to reset a suspended port if the attached
3557 	 * device is enabled for remote wakeup.  Hence the reset
3558 	 * operation is carried out here, after the port has been
3559 	 * resumed.
3560 	 */
3561 	if (udev->reset_resume) {
3562 		/*
3563 		 * If the device morphs or switches modes when it is reset,
3564 		 * we don't want to perform a reset-resume.  We'll fail the
3565 		 * resume, which will cause a logical disconnect, and then
3566 		 * the device will be rediscovered.
3567 		 */
3568  retry_reset_resume:
3569 		if (udev->quirks & USB_QUIRK_RESET)
3570 			status = -ENODEV;
3571 		else
3572 			status = usb_reset_and_verify_device(udev);
3573 	}
3574 
3575 	/* 10.5.4.5 says be sure devices in the tree are still there.
3576 	 * For now let's assume the device didn't go crazy on resume,
3577 	 * and device drivers will know about any resume quirks.
3578 	 */
3579 	if (status == 0) {
3580 		devstatus = 0;
3581 		status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3582 
3583 		/* If a normal resume failed, try doing a reset-resume */
3584 		if (status && !udev->reset_resume && udev->persist_enabled) {
3585 			dev_dbg(&udev->dev, "retry with reset-resume\n");
3586 			udev->reset_resume = 1;
3587 			goto retry_reset_resume;
3588 		}
3589 	}
3590 
3591 	if (status) {
3592 		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3593 				status);
3594 	/*
3595 	 * There are a few quirky devices which violate the standard
3596 	 * by claiming to have remote wakeup enabled after a reset,
3597 	 * which crash if the feature is cleared, hence check for
3598 	 * udev->reset_resume
3599 	 */
3600 	} else if (udev->actconfig && !udev->reset_resume) {
3601 		if (udev->speed < USB_SPEED_SUPER) {
3602 			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3603 				status = usb_disable_remote_wakeup(udev);
3604 		} else {
3605 			status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
3606 					&devstatus);
3607 			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3608 					| USB_INTRF_STAT_FUNC_RW))
3609 				status = usb_disable_remote_wakeup(udev);
3610 		}
3611 
3612 		if (status)
3613 			dev_dbg(&udev->dev,
3614 				"disable remote wakeup, status %d\n",
3615 				status);
3616 		status = 0;
3617 	}
3618 	return status;
3619 }
3620 
3621 /*
3622  * There are some SS USB devices which take longer time for link training.
3623  * XHCI specs 4.19.4 says that when Link training is successful, port
3624  * sets CCS bit to 1. So if SW reads port status before successful link
3625  * training, then it will not find device to be present.
3626  * USB Analyzer log with such buggy devices show that in some cases
3627  * device switch on the RX termination after long delay of host enabling
3628  * the VBUS. In few other cases it has been seen that device fails to
3629  * negotiate link training in first attempt. It has been
3630  * reported till now that few devices take as long as 2000 ms to train
3631  * the link after host enabling its VBUS and termination. Following
3632  * routine implements a 2000 ms timeout for link training. If in a case
3633  * link trains before timeout, loop will exit earlier.
3634  *
3635  * There are also some 2.0 hard drive based devices and 3.0 thumb
3636  * drives that, when plugged into a 2.0 only port, take a long
3637  * time to set CCS after VBUS enable.
3638  *
3639  * FIXME: If a device was connected before suspend, but was removed
3640  * while system was asleep, then the loop in the following routine will
3641  * only exit at timeout.
3642  *
3643  * This routine should only be called when persist is enabled.
3644  */
wait_for_connected(struct usb_device * udev,struct usb_hub * hub,int port1,u16 * portchange,u16 * portstatus)3645 static int wait_for_connected(struct usb_device *udev,
3646 		struct usb_hub *hub, int port1,
3647 		u16 *portchange, u16 *portstatus)
3648 {
3649 	int status = 0, delay_ms = 0;
3650 
3651 	while (delay_ms < 2000) {
3652 		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3653 			break;
3654 		if (!usb_port_is_power_on(hub, *portstatus)) {
3655 			status = -ENODEV;
3656 			break;
3657 		}
3658 		msleep(20);
3659 		delay_ms += 20;
3660 		status = usb_hub_port_status(hub, port1, portstatus, portchange);
3661 	}
3662 	dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3663 	return status;
3664 }
3665 
3666 /*
3667  * usb_port_resume - re-activate a suspended usb device's upstream port
3668  * @udev: device to re-activate, not a root hub
3669  * Context: must be able to sleep; device not locked; pm locks held
3670  *
3671  * This will re-activate the suspended device, increasing power usage
3672  * while letting drivers communicate again with its endpoints.
3673  * USB resume explicitly guarantees that the power session between
3674  * the host and the device is the same as it was when the device
3675  * suspended.
3676  *
3677  * If @udev->reset_resume is set then this routine won't check that the
3678  * port is still enabled.  Furthermore, finish_port_resume() above will
3679  * reset @udev.  The end result is that a broken power session can be
3680  * recovered and @udev will appear to persist across a loss of VBUS power.
3681  *
3682  * For example, if a host controller doesn't maintain VBUS suspend current
3683  * during a system sleep or is reset when the system wakes up, all the USB
3684  * power sessions below it will be broken.  This is especially troublesome
3685  * for mass-storage devices containing mounted filesystems, since the
3686  * device will appear to have disconnected and all the memory mappings
3687  * to it will be lost.  Using the USB_PERSIST facility, the device can be
3688  * made to appear as if it had not disconnected.
3689  *
3690  * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3691  * every effort to insure that the same device is present after the
3692  * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3693  * quite possible for a device to remain unaltered but its media to be
3694  * changed.  If the user replaces a flash memory card while the system is
3695  * asleep, he will have only himself to blame when the filesystem on the
3696  * new card is corrupted and the system crashes.
3697  *
3698  * Returns 0 on success, else negative errno.
3699  */
usb_port_resume(struct usb_device * udev,pm_message_t msg)3700 int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3701 {
3702 	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3703 	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3704 	int		port1 = udev->portnum;
3705 	int		status;
3706 	u16		portchange, portstatus;
3707 
3708 	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3709 		status = pm_runtime_resume_and_get(&port_dev->dev);
3710 		if (status < 0) {
3711 			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3712 					status);
3713 			return status;
3714 		}
3715 	}
3716 
3717 	usb_lock_port(port_dev);
3718 
3719 	/* Skip the initial Clear-Suspend step for a remote wakeup */
3720 	status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3721 	if (status == 0 && !port_is_suspended(hub, portstatus)) {
3722 		if (portchange & USB_PORT_STAT_C_SUSPEND)
3723 			pm_wakeup_event(&udev->dev, 0);
3724 		goto SuspendCleared;
3725 	}
3726 
3727 	/* see 7.1.7.7; affects power usage, but not budgeting */
3728 	if (hub_is_superspeed(hub->hdev))
3729 		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3730 	else
3731 		status = usb_clear_port_feature(hub->hdev,
3732 				port1, USB_PORT_FEAT_SUSPEND);
3733 	if (status) {
3734 		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3735 	} else {
3736 		/* drive resume for USB_RESUME_TIMEOUT msec */
3737 		dev_dbg(&udev->dev, "usb %sresume\n",
3738 				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
3739 		msleep(USB_RESUME_TIMEOUT);
3740 
3741 		/* Virtual root hubs can trigger on GET_PORT_STATUS to
3742 		 * stop resume signaling.  Then finish the resume
3743 		 * sequence.
3744 		 */
3745 		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3746 	}
3747 
3748  SuspendCleared:
3749 	if (status == 0) {
3750 		udev->port_is_suspended = 0;
3751 		if (hub_is_superspeed(hub->hdev)) {
3752 			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3753 				usb_clear_port_feature(hub->hdev, port1,
3754 					USB_PORT_FEAT_C_PORT_LINK_STATE);
3755 		} else {
3756 			if (portchange & USB_PORT_STAT_C_SUSPEND)
3757 				usb_clear_port_feature(hub->hdev, port1,
3758 						USB_PORT_FEAT_C_SUSPEND);
3759 		}
3760 
3761 		/* TRSMRCY = 10 msec */
3762 		msleep(10);
3763 	}
3764 
3765 	if (udev->persist_enabled)
3766 		status = wait_for_connected(udev, hub, port1, &portchange,
3767 				&portstatus);
3768 
3769 	status = check_port_resume_type(udev,
3770 			hub, port1, status, portchange, portstatus);
3771 	if (status == 0)
3772 		status = finish_port_resume(udev);
3773 	if (status < 0) {
3774 		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3775 		hub_port_logical_disconnect(hub, port1);
3776 	} else  {
3777 		/* Try to enable USB2 hardware LPM */
3778 		usb_enable_usb2_hardware_lpm(udev);
3779 
3780 		/* Try to enable USB3 LTM */
3781 		usb_enable_ltm(udev);
3782 	}
3783 
3784 	usb_unlock_port(port_dev);
3785 
3786 	return status;
3787 }
3788 
usb_remote_wakeup(struct usb_device * udev)3789 int usb_remote_wakeup(struct usb_device *udev)
3790 {
3791 	int	status = 0;
3792 
3793 	usb_lock_device(udev);
3794 	if (udev->state == USB_STATE_SUSPENDED) {
3795 		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3796 		status = usb_autoresume_device(udev);
3797 		if (status == 0) {
3798 			/* Let the drivers do their thing, then... */
3799 			usb_autosuspend_device(udev);
3800 		}
3801 	}
3802 	usb_unlock_device(udev);
3803 	return status;
3804 }
3805 
3806 /* Returns 1 if there was a remote wakeup and a connect status change. */
hub_handle_remote_wakeup(struct usb_hub * hub,unsigned int port,u16 portstatus,u16 portchange)3807 static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3808 		u16 portstatus, u16 portchange)
3809 		__must_hold(&port_dev->status_lock)
3810 {
3811 	struct usb_port *port_dev = hub->ports[port - 1];
3812 	struct usb_device *hdev;
3813 	struct usb_device *udev;
3814 	int connect_change = 0;
3815 	u16 link_state;
3816 	int ret;
3817 
3818 	hdev = hub->hdev;
3819 	udev = port_dev->child;
3820 	if (!hub_is_superspeed(hdev)) {
3821 		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3822 			return 0;
3823 		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3824 	} else {
3825 		link_state = portstatus & USB_PORT_STAT_LINK_STATE;
3826 		if (!udev || udev->state != USB_STATE_SUSPENDED ||
3827 				(link_state != USB_SS_PORT_LS_U0 &&
3828 				 link_state != USB_SS_PORT_LS_U1 &&
3829 				 link_state != USB_SS_PORT_LS_U2))
3830 			return 0;
3831 	}
3832 
3833 	if (udev) {
3834 		/* TRSMRCY = 10 msec */
3835 		msleep(10);
3836 
3837 		usb_unlock_port(port_dev);
3838 		ret = usb_remote_wakeup(udev);
3839 		usb_lock_port(port_dev);
3840 		if (ret < 0)
3841 			connect_change = 1;
3842 	} else {
3843 		ret = -ENODEV;
3844 		hub_port_disable(hub, port, 1);
3845 	}
3846 	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3847 	return connect_change;
3848 }
3849 
check_ports_changed(struct usb_hub * hub)3850 static int check_ports_changed(struct usb_hub *hub)
3851 {
3852 	int port1;
3853 
3854 	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3855 		u16 portstatus, portchange;
3856 		int status;
3857 
3858 		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3859 		if (!status && portchange)
3860 			return 1;
3861 	}
3862 	return 0;
3863 }
3864 
hub_suspend(struct usb_interface * intf,pm_message_t msg)3865 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3866 {
3867 	struct usb_hub		*hub = usb_get_intfdata(intf);
3868 	struct usb_device	*hdev = hub->hdev;
3869 	unsigned		port1;
3870 
3871 	/*
3872 	 * Warn if children aren't already suspended.
3873 	 * Also, add up the number of wakeup-enabled descendants.
3874 	 */
3875 	hub->wakeup_enabled_descendants = 0;
3876 	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3877 		struct usb_port *port_dev = hub->ports[port1 - 1];
3878 		struct usb_device *udev = port_dev->child;
3879 
3880 		if (udev && udev->can_submit) {
3881 			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3882 					dev_name(&udev->dev));
3883 			if (PMSG_IS_AUTO(msg))
3884 				return -EBUSY;
3885 		}
3886 		if (udev)
3887 			hub->wakeup_enabled_descendants +=
3888 					usb_wakeup_enabled_descendants(udev);
3889 	}
3890 
3891 	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3892 		/* check if there are changes pending on hub ports */
3893 		if (check_ports_changed(hub)) {
3894 			if (PMSG_IS_AUTO(msg))
3895 				return -EBUSY;
3896 			pm_wakeup_event(&hdev->dev, 2000);
3897 		}
3898 	}
3899 
3900 	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3901 		/* Enable hub to send remote wakeup for all ports. */
3902 		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3903 			set_port_feature(hdev,
3904 					 port1 |
3905 					 USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3906 					 USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3907 					 USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3908 					 USB_PORT_FEAT_REMOTE_WAKE_MASK);
3909 		}
3910 	}
3911 
3912 	dev_dbg(&intf->dev, "%s\n", __func__);
3913 
3914 	/* stop hub_wq and related activity */
3915 	hub_quiesce(hub, HUB_SUSPEND);
3916 	return 0;
3917 }
3918 
3919 /* Report wakeup requests from the ports of a resuming root hub */
report_wakeup_requests(struct usb_hub * hub)3920 static void report_wakeup_requests(struct usb_hub *hub)
3921 {
3922 	struct usb_device	*hdev = hub->hdev;
3923 	struct usb_device	*udev;
3924 	struct usb_hcd		*hcd;
3925 	unsigned long		resuming_ports;
3926 	int			i;
3927 
3928 	if (hdev->parent)
3929 		return;		/* Not a root hub */
3930 
3931 	hcd = bus_to_hcd(hdev->bus);
3932 	if (hcd->driver->get_resuming_ports) {
3933 
3934 		/*
3935 		 * The get_resuming_ports() method returns a bitmap (origin 0)
3936 		 * of ports which have started wakeup signaling but have not
3937 		 * yet finished resuming.  During system resume we will
3938 		 * resume all the enabled ports, regardless of any wakeup
3939 		 * signals, which means the wakeup requests would be lost.
3940 		 * To prevent this, report them to the PM core here.
3941 		 */
3942 		resuming_ports = hcd->driver->get_resuming_ports(hcd);
3943 		for (i = 0; i < hdev->maxchild; ++i) {
3944 			if (test_bit(i, &resuming_ports)) {
3945 				udev = hub->ports[i]->child;
3946 				if (udev)
3947 					pm_wakeup_event(&udev->dev, 0);
3948 			}
3949 		}
3950 	}
3951 }
3952 
hub_resume(struct usb_interface * intf)3953 static int hub_resume(struct usb_interface *intf)
3954 {
3955 	struct usb_hub *hub = usb_get_intfdata(intf);
3956 
3957 	dev_dbg(&intf->dev, "%s\n", __func__);
3958 	hub_activate(hub, HUB_RESUME);
3959 
3960 	/*
3961 	 * This should be called only for system resume, not runtime resume.
3962 	 * We can't tell the difference here, so some wakeup requests will be
3963 	 * reported at the wrong time or more than once.  This shouldn't
3964 	 * matter much, so long as they do get reported.
3965 	 */
3966 	report_wakeup_requests(hub);
3967 	return 0;
3968 }
3969 
hub_reset_resume(struct usb_interface * intf)3970 static int hub_reset_resume(struct usb_interface *intf)
3971 {
3972 	struct usb_hub *hub = usb_get_intfdata(intf);
3973 
3974 	dev_dbg(&intf->dev, "%s\n", __func__);
3975 	hub_activate(hub, HUB_RESET_RESUME);
3976 	return 0;
3977 }
3978 
3979 /**
3980  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
3981  * @rhdev: struct usb_device for the root hub
3982  *
3983  * The USB host controller driver calls this function when its root hub
3984  * is resumed and Vbus power has been interrupted or the controller
3985  * has been reset.  The routine marks @rhdev as having lost power.
3986  * When the hub driver is resumed it will take notice and carry out
3987  * power-session recovery for all the "USB-PERSIST"-enabled child devices;
3988  * the others will be disconnected.
3989  */
usb_root_hub_lost_power(struct usb_device * rhdev)3990 void usb_root_hub_lost_power(struct usb_device *rhdev)
3991 {
3992 	dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
3993 	rhdev->reset_resume = 1;
3994 }
3995 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
3996 
3997 static const char * const usb3_lpm_names[]  = {
3998 	"U0",
3999 	"U1",
4000 	"U2",
4001 	"U3",
4002 };
4003 
4004 /*
4005  * Send a Set SEL control transfer to the device, prior to enabling
4006  * device-initiated U1 or U2.  This lets the device know the exit latencies from
4007  * the time the device initiates a U1 or U2 exit, to the time it will receive a
4008  * packet from the host.
4009  *
4010  * This function will fail if the SEL or PEL values for udev are greater than
4011  * the maximum allowed values for the link state to be enabled.
4012  */
usb_req_set_sel(struct usb_device * udev)4013 static int usb_req_set_sel(struct usb_device *udev)
4014 {
4015 	struct usb_set_sel_req *sel_values;
4016 	unsigned long long u1_sel;
4017 	unsigned long long u1_pel;
4018 	unsigned long long u2_sel;
4019 	unsigned long long u2_pel;
4020 	int ret;
4021 
4022 	if (!udev->parent || udev->speed < USB_SPEED_SUPER || !udev->lpm_capable)
4023 		return 0;
4024 
4025 	/* Convert SEL and PEL stored in ns to us */
4026 	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4027 	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
4028 	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4029 	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
4030 
4031 	/*
4032 	 * Make sure that the calculated SEL and PEL values for the link
4033 	 * state we're enabling aren't bigger than the max SEL/PEL
4034 	 * value that will fit in the SET SEL control transfer.
4035 	 * Otherwise the device would get an incorrect idea of the exit
4036 	 * latency for the link state, and could start a device-initiated
4037 	 * U1/U2 when the exit latencies are too high.
4038 	 */
4039 	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
4040 	    u1_pel > USB3_LPM_MAX_U1_SEL_PEL ||
4041 	    u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
4042 	    u2_pel > USB3_LPM_MAX_U2_SEL_PEL) {
4043 		dev_dbg(&udev->dev, "Device-initiated U1/U2 disabled due to long SEL or PEL\n");
4044 		return -EINVAL;
4045 	}
4046 
4047 	/*
4048 	 * usb_enable_lpm() can be called as part of a failed device reset,
4049 	 * which may be initiated by an error path of a mass storage driver.
4050 	 * Therefore, use GFP_NOIO.
4051 	 */
4052 	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
4053 	if (!sel_values)
4054 		return -ENOMEM;
4055 
4056 	sel_values->u1_sel = u1_sel;
4057 	sel_values->u1_pel = u1_pel;
4058 	sel_values->u2_sel = cpu_to_le16(u2_sel);
4059 	sel_values->u2_pel = cpu_to_le16(u2_pel);
4060 
4061 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4062 			USB_REQ_SET_SEL,
4063 			USB_RECIP_DEVICE,
4064 			0, 0,
4065 			sel_values, sizeof *(sel_values),
4066 			USB_CTRL_SET_TIMEOUT);
4067 	kfree(sel_values);
4068 
4069 	if (ret > 0)
4070 		udev->lpm_devinit_allow = 1;
4071 
4072 	return ret;
4073 }
4074 
4075 /*
4076  * Enable or disable device-initiated U1 or U2 transitions.
4077  */
usb_set_device_initiated_lpm(struct usb_device * udev,enum usb3_link_state state,bool enable)4078 static int usb_set_device_initiated_lpm(struct usb_device *udev,
4079 		enum usb3_link_state state, bool enable)
4080 {
4081 	int ret;
4082 	int feature;
4083 
4084 	switch (state) {
4085 	case USB3_LPM_U1:
4086 		feature = USB_DEVICE_U1_ENABLE;
4087 		break;
4088 	case USB3_LPM_U2:
4089 		feature = USB_DEVICE_U2_ENABLE;
4090 		break;
4091 	default:
4092 		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
4093 				__func__, enable ? "enable" : "disable");
4094 		return -EINVAL;
4095 	}
4096 
4097 	if (udev->state != USB_STATE_CONFIGURED) {
4098 		dev_dbg(&udev->dev, "%s: Can't %s %s state "
4099 				"for unconfigured device.\n",
4100 				__func__, enable ? "enable" : "disable",
4101 				usb3_lpm_names[state]);
4102 		return 0;
4103 	}
4104 
4105 	if (enable) {
4106 		/*
4107 		 * Now send the control transfer to enable device-initiated LPM
4108 		 * for either U1 or U2.
4109 		 */
4110 		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4111 				USB_REQ_SET_FEATURE,
4112 				USB_RECIP_DEVICE,
4113 				feature,
4114 				0, NULL, 0,
4115 				USB_CTRL_SET_TIMEOUT);
4116 	} else {
4117 		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4118 				USB_REQ_CLEAR_FEATURE,
4119 				USB_RECIP_DEVICE,
4120 				feature,
4121 				0, NULL, 0,
4122 				USB_CTRL_SET_TIMEOUT);
4123 	}
4124 	if (ret < 0) {
4125 		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
4126 				enable ? "Enable" : "Disable",
4127 				usb3_lpm_names[state]);
4128 		return -EBUSY;
4129 	}
4130 	return 0;
4131 }
4132 
usb_set_lpm_timeout(struct usb_device * udev,enum usb3_link_state state,int timeout)4133 static int usb_set_lpm_timeout(struct usb_device *udev,
4134 		enum usb3_link_state state, int timeout)
4135 {
4136 	int ret;
4137 	int feature;
4138 
4139 	switch (state) {
4140 	case USB3_LPM_U1:
4141 		feature = USB_PORT_FEAT_U1_TIMEOUT;
4142 		break;
4143 	case USB3_LPM_U2:
4144 		feature = USB_PORT_FEAT_U2_TIMEOUT;
4145 		break;
4146 	default:
4147 		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
4148 				__func__);
4149 		return -EINVAL;
4150 	}
4151 
4152 	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
4153 			timeout != USB3_LPM_DEVICE_INITIATED) {
4154 		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
4155 				"which is a reserved value.\n",
4156 				usb3_lpm_names[state], timeout);
4157 		return -EINVAL;
4158 	}
4159 
4160 	ret = set_port_feature(udev->parent,
4161 			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
4162 			feature);
4163 	if (ret < 0) {
4164 		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
4165 				"error code %i\n", usb3_lpm_names[state],
4166 				timeout, ret);
4167 		return -EBUSY;
4168 	}
4169 	if (state == USB3_LPM_U1)
4170 		udev->u1_params.timeout = timeout;
4171 	else
4172 		udev->u2_params.timeout = timeout;
4173 	return 0;
4174 }
4175 
4176 /*
4177  * Don't allow device intiated U1/U2 if the system exit latency + one bus
4178  * interval is greater than the minimum service interval of any active
4179  * periodic endpoint. See USB 3.2 section 9.4.9
4180  */
usb_device_may_initiate_lpm(struct usb_device * udev,enum usb3_link_state state)4181 static bool usb_device_may_initiate_lpm(struct usb_device *udev,
4182 					enum usb3_link_state state)
4183 {
4184 	unsigned int sel;		/* us */
4185 	int i, j;
4186 
4187 	if (!udev->lpm_devinit_allow)
4188 		return false;
4189 
4190 	if (state == USB3_LPM_U1)
4191 		sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4192 	else if (state == USB3_LPM_U2)
4193 		sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4194 	else
4195 		return false;
4196 
4197 	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
4198 		struct usb_interface *intf;
4199 		struct usb_endpoint_descriptor *desc;
4200 		unsigned int interval;
4201 
4202 		intf = udev->actconfig->interface[i];
4203 		if (!intf)
4204 			continue;
4205 
4206 		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++) {
4207 			desc = &intf->cur_altsetting->endpoint[j].desc;
4208 
4209 			if (usb_endpoint_xfer_int(desc) ||
4210 			    usb_endpoint_xfer_isoc(desc)) {
4211 				interval = (1 << (desc->bInterval - 1)) * 125;
4212 				if (sel + 125 > interval)
4213 					return false;
4214 			}
4215 		}
4216 	}
4217 	return true;
4218 }
4219 
4220 /*
4221  * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
4222  * U1/U2 entry.
4223  *
4224  * We will attempt to enable U1 or U2, but there are no guarantees that the
4225  * control transfers to set the hub timeout or enable device-initiated U1/U2
4226  * will be successful.
4227  *
4228  * If the control transfer to enable device-initiated U1/U2 entry fails, then
4229  * hub-initiated U1/U2 will be disabled.
4230  *
4231  * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
4232  * driver know about it.  If that call fails, it should be harmless, and just
4233  * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
4234  */
usb_enable_link_state(struct usb_hcd * hcd,struct usb_device * udev,enum usb3_link_state state)4235 static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4236 		enum usb3_link_state state)
4237 {
4238 	int timeout;
4239 	__u8 u1_mel;
4240 	__le16 u2_mel;
4241 
4242 	/* Skip if the device BOS descriptor couldn't be read */
4243 	if (!udev->bos)
4244 		return;
4245 
4246 	u1_mel = udev->bos->ss_cap->bU1devExitLat;
4247 	u2_mel = udev->bos->ss_cap->bU2DevExitLat;
4248 
4249 	/* If the device says it doesn't have *any* exit latency to come out of
4250 	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
4251 	 * state.
4252 	 */
4253 	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
4254 			(state == USB3_LPM_U2 && u2_mel == 0))
4255 		return;
4256 
4257 	/* We allow the host controller to set the U1/U2 timeout internally
4258 	 * first, so that it can change its schedule to account for the
4259 	 * additional latency to send data to a device in a lower power
4260 	 * link state.
4261 	 */
4262 	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
4263 
4264 	/* xHCI host controller doesn't want to enable this LPM state. */
4265 	if (timeout == 0)
4266 		return;
4267 
4268 	if (timeout < 0) {
4269 		dev_warn(&udev->dev, "Could not enable %s link state, "
4270 				"xHCI error %i.\n", usb3_lpm_names[state],
4271 				timeout);
4272 		return;
4273 	}
4274 
4275 	if (usb_set_lpm_timeout(udev, state, timeout)) {
4276 		/* If we can't set the parent hub U1/U2 timeout,
4277 		 * device-initiated LPM won't be allowed either, so let the xHCI
4278 		 * host know that this link state won't be enabled.
4279 		 */
4280 		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4281 		return;
4282 	}
4283 
4284 	/* Only a configured device will accept the Set Feature
4285 	 * U1/U2_ENABLE
4286 	 */
4287 	if (udev->actconfig &&
4288 	    usb_device_may_initiate_lpm(udev, state)) {
4289 		if (usb_set_device_initiated_lpm(udev, state, true)) {
4290 			/*
4291 			 * Request to enable device initiated U1/U2 failed,
4292 			 * better to turn off lpm in this case.
4293 			 */
4294 			usb_set_lpm_timeout(udev, state, 0);
4295 			hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4296 			return;
4297 		}
4298 	}
4299 
4300 	if (state == USB3_LPM_U1)
4301 		udev->usb3_lpm_u1_enabled = 1;
4302 	else if (state == USB3_LPM_U2)
4303 		udev->usb3_lpm_u2_enabled = 1;
4304 }
4305 /*
4306  * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
4307  * U1/U2 entry.
4308  *
4309  * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
4310  * If zero is returned, the parent will not allow the link to go into U1/U2.
4311  *
4312  * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
4313  * it won't have an effect on the bus link state because the parent hub will
4314  * still disallow device-initiated U1/U2 entry.
4315  *
4316  * If zero is returned, the xHCI host controller may still think U1/U2 entry is
4317  * possible.  The result will be slightly more bus bandwidth will be taken up
4318  * (to account for U1/U2 exit latency), but it should be harmless.
4319  */
usb_disable_link_state(struct usb_hcd * hcd,struct usb_device * udev,enum usb3_link_state state)4320 static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4321 		enum usb3_link_state state)
4322 {
4323 	switch (state) {
4324 	case USB3_LPM_U1:
4325 	case USB3_LPM_U2:
4326 		break;
4327 	default:
4328 		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4329 				__func__);
4330 		return -EINVAL;
4331 	}
4332 
4333 	if (usb_set_lpm_timeout(udev, state, 0))
4334 		return -EBUSY;
4335 
4336 	usb_set_device_initiated_lpm(udev, state, false);
4337 
4338 	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4339 		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4340 				"bus schedule bandwidth may be impacted.\n",
4341 				usb3_lpm_names[state]);
4342 
4343 	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4344 	 * is disabled. Hub will disallows link to enter U1/U2 as well,
4345 	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
4346 	 * timeout set to 0, no matter device-initiated LPM is disabled or
4347 	 * not.
4348 	 */
4349 	if (state == USB3_LPM_U1)
4350 		udev->usb3_lpm_u1_enabled = 0;
4351 	else if (state == USB3_LPM_U2)
4352 		udev->usb3_lpm_u2_enabled = 0;
4353 
4354 	return 0;
4355 }
4356 
4357 /*
4358  * Disable hub-initiated and device-initiated U1 and U2 entry.
4359  * Caller must own the bandwidth_mutex.
4360  *
4361  * This will call usb_enable_lpm() on failure, which will decrement
4362  * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4363  */
usb_disable_lpm(struct usb_device * udev)4364 int usb_disable_lpm(struct usb_device *udev)
4365 {
4366 	struct usb_hcd *hcd;
4367 
4368 	if (!udev || !udev->parent ||
4369 			udev->speed < USB_SPEED_SUPER ||
4370 			!udev->lpm_capable ||
4371 			udev->state < USB_STATE_CONFIGURED)
4372 		return 0;
4373 
4374 	hcd = bus_to_hcd(udev->bus);
4375 	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4376 		return 0;
4377 
4378 	udev->lpm_disable_count++;
4379 	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4380 		return 0;
4381 
4382 	/* If LPM is enabled, attempt to disable it. */
4383 	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4384 		goto enable_lpm;
4385 	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4386 		goto enable_lpm;
4387 
4388 	return 0;
4389 
4390 enable_lpm:
4391 	usb_enable_lpm(udev);
4392 	return -EBUSY;
4393 }
4394 EXPORT_SYMBOL_GPL(usb_disable_lpm);
4395 
4396 /* Grab the bandwidth_mutex before calling usb_disable_lpm() */
usb_unlocked_disable_lpm(struct usb_device * udev)4397 int usb_unlocked_disable_lpm(struct usb_device *udev)
4398 {
4399 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4400 	int ret;
4401 
4402 	if (!hcd)
4403 		return -EINVAL;
4404 
4405 	mutex_lock(hcd->bandwidth_mutex);
4406 	ret = usb_disable_lpm(udev);
4407 	mutex_unlock(hcd->bandwidth_mutex);
4408 
4409 	return ret;
4410 }
4411 EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4412 
4413 /*
4414  * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4415  * xHCI host policy may prevent U1 or U2 from being enabled.
4416  *
4417  * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4418  * until the lpm_disable_count drops to zero.  Caller must own the
4419  * bandwidth_mutex.
4420  */
usb_enable_lpm(struct usb_device * udev)4421 void usb_enable_lpm(struct usb_device *udev)
4422 {
4423 	struct usb_hcd *hcd;
4424 	struct usb_hub *hub;
4425 	struct usb_port *port_dev;
4426 
4427 	if (!udev || !udev->parent ||
4428 			udev->speed < USB_SPEED_SUPER ||
4429 			!udev->lpm_capable ||
4430 			udev->state < USB_STATE_CONFIGURED)
4431 		return;
4432 
4433 	udev->lpm_disable_count--;
4434 	hcd = bus_to_hcd(udev->bus);
4435 	/* Double check that we can both enable and disable LPM.
4436 	 * Device must be configured to accept set feature U1/U2 timeout.
4437 	 */
4438 	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4439 			!hcd->driver->disable_usb3_lpm_timeout)
4440 		return;
4441 
4442 	if (udev->lpm_disable_count > 0)
4443 		return;
4444 
4445 	hub = usb_hub_to_struct_hub(udev->parent);
4446 	if (!hub)
4447 		return;
4448 
4449 	port_dev = hub->ports[udev->portnum - 1];
4450 
4451 	if (port_dev->usb3_lpm_u1_permit)
4452 		usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4453 
4454 	if (port_dev->usb3_lpm_u2_permit)
4455 		usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4456 }
4457 EXPORT_SYMBOL_GPL(usb_enable_lpm);
4458 
4459 /* Grab the bandwidth_mutex before calling usb_enable_lpm() */
usb_unlocked_enable_lpm(struct usb_device * udev)4460 void usb_unlocked_enable_lpm(struct usb_device *udev)
4461 {
4462 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4463 
4464 	if (!hcd)
4465 		return;
4466 
4467 	mutex_lock(hcd->bandwidth_mutex);
4468 	usb_enable_lpm(udev);
4469 	mutex_unlock(hcd->bandwidth_mutex);
4470 }
4471 EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4472 
4473 /* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
hub_usb3_port_prepare_disable(struct usb_hub * hub,struct usb_port * port_dev)4474 static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4475 					  struct usb_port *port_dev)
4476 {
4477 	struct usb_device *udev = port_dev->child;
4478 	int ret;
4479 
4480 	if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
4481 		ret = hub_set_port_link_state(hub, port_dev->portnum,
4482 					      USB_SS_PORT_LS_U0);
4483 		if (!ret) {
4484 			msleep(USB_RESUME_TIMEOUT);
4485 			ret = usb_disable_remote_wakeup(udev);
4486 		}
4487 		if (ret)
4488 			dev_warn(&udev->dev,
4489 				 "Port disable: can't disable remote wake\n");
4490 		udev->do_remote_wakeup = 0;
4491 	}
4492 }
4493 
4494 #else	/* CONFIG_PM */
4495 
4496 #define hub_suspend		NULL
4497 #define hub_resume		NULL
4498 #define hub_reset_resume	NULL
4499 
hub_usb3_port_prepare_disable(struct usb_hub * hub,struct usb_port * port_dev)4500 static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4501 						 struct usb_port *port_dev) { }
4502 
usb_disable_lpm(struct usb_device * udev)4503 int usb_disable_lpm(struct usb_device *udev)
4504 {
4505 	return 0;
4506 }
4507 EXPORT_SYMBOL_GPL(usb_disable_lpm);
4508 
usb_enable_lpm(struct usb_device * udev)4509 void usb_enable_lpm(struct usb_device *udev) { }
4510 EXPORT_SYMBOL_GPL(usb_enable_lpm);
4511 
usb_unlocked_disable_lpm(struct usb_device * udev)4512 int usb_unlocked_disable_lpm(struct usb_device *udev)
4513 {
4514 	return 0;
4515 }
4516 EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4517 
usb_unlocked_enable_lpm(struct usb_device * udev)4518 void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4519 EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4520 
usb_disable_ltm(struct usb_device * udev)4521 int usb_disable_ltm(struct usb_device *udev)
4522 {
4523 	return 0;
4524 }
4525 EXPORT_SYMBOL_GPL(usb_disable_ltm);
4526 
usb_enable_ltm(struct usb_device * udev)4527 void usb_enable_ltm(struct usb_device *udev) { }
4528 EXPORT_SYMBOL_GPL(usb_enable_ltm);
4529 
hub_handle_remote_wakeup(struct usb_hub * hub,unsigned int port,u16 portstatus,u16 portchange)4530 static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4531 		u16 portstatus, u16 portchange)
4532 {
4533 	return 0;
4534 }
4535 
usb_req_set_sel(struct usb_device * udev)4536 static int usb_req_set_sel(struct usb_device *udev)
4537 {
4538 	return 0;
4539 }
4540 
4541 #endif	/* CONFIG_PM */
4542 
4543 /*
4544  * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
4545  * a connection with a plugged-in cable but will signal the host when the cable
4546  * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
4547  */
hub_port_disable(struct usb_hub * hub,int port1,int set_state)4548 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
4549 {
4550 	struct usb_port *port_dev = hub->ports[port1 - 1];
4551 	struct usb_device *hdev = hub->hdev;
4552 	int ret = 0;
4553 
4554 	if (!hub->error) {
4555 		if (hub_is_superspeed(hub->hdev)) {
4556 			hub_usb3_port_prepare_disable(hub, port_dev);
4557 			ret = hub_set_port_link_state(hub, port_dev->portnum,
4558 						      USB_SS_PORT_LS_U3);
4559 		} else {
4560 			ret = usb_clear_port_feature(hdev, port1,
4561 					USB_PORT_FEAT_ENABLE);
4562 		}
4563 	}
4564 	if (port_dev->child && set_state)
4565 		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
4566 	if (ret && ret != -ENODEV)
4567 		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
4568 	return ret;
4569 }
4570 
4571 /*
4572  * usb_port_disable - disable a usb device's upstream port
4573  * @udev: device to disable
4574  * Context: @udev locked, must be able to sleep.
4575  *
4576  * Disables a USB device that isn't in active use.
4577  */
usb_port_disable(struct usb_device * udev)4578 int usb_port_disable(struct usb_device *udev)
4579 {
4580 	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4581 
4582 	return hub_port_disable(hub, udev->portnum, 0);
4583 }
4584 
4585 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4586  *
4587  * Between connect detection and reset signaling there must be a delay
4588  * of 100ms at least for debounce and power-settling.  The corresponding
4589  * timer shall restart whenever the downstream port detects a disconnect.
4590  *
4591  * Apparently there are some bluetooth and irda-dongles and a number of
4592  * low-speed devices for which this debounce period may last over a second.
4593  * Not covered by the spec - but easy to deal with.
4594  *
4595  * This implementation uses a 1500ms total debounce timeout; if the
4596  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4597  * every 25ms for transient disconnects.  When the port status has been
4598  * unchanged for 100ms it returns the port status.
4599  */
hub_port_debounce(struct usb_hub * hub,int port1,bool must_be_connected)4600 int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4601 {
4602 	int ret;
4603 	u16 portchange, portstatus;
4604 	unsigned connection = 0xffff;
4605 	int total_time, stable_time = 0;
4606 	struct usb_port *port_dev = hub->ports[port1 - 1];
4607 
4608 	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4609 		ret = usb_hub_port_status(hub, port1, &portstatus, &portchange);
4610 		if (ret < 0)
4611 			return ret;
4612 
4613 		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4614 		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4615 			if (!must_be_connected ||
4616 			     (connection == USB_PORT_STAT_CONNECTION))
4617 				stable_time += HUB_DEBOUNCE_STEP;
4618 			if (stable_time >= HUB_DEBOUNCE_STABLE)
4619 				break;
4620 		} else {
4621 			stable_time = 0;
4622 			connection = portstatus & USB_PORT_STAT_CONNECTION;
4623 		}
4624 
4625 		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4626 			usb_clear_port_feature(hub->hdev, port1,
4627 					USB_PORT_FEAT_C_CONNECTION);
4628 		}
4629 
4630 		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4631 			break;
4632 		msleep(HUB_DEBOUNCE_STEP);
4633 	}
4634 
4635 	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4636 			total_time, stable_time, portstatus);
4637 
4638 	if (stable_time < HUB_DEBOUNCE_STABLE)
4639 		return -ETIMEDOUT;
4640 	return portstatus;
4641 }
4642 
usb_ep0_reinit(struct usb_device * udev)4643 void usb_ep0_reinit(struct usb_device *udev)
4644 {
4645 	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4646 	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4647 	usb_enable_endpoint(udev, &udev->ep0, true);
4648 }
4649 EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4650 
4651 #define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
4652 #define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
4653 
hub_set_address(struct usb_device * udev,int devnum)4654 static int hub_set_address(struct usb_device *udev, int devnum)
4655 {
4656 	int retval;
4657 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4658 
4659 	/*
4660 	 * The host controller will choose the device address,
4661 	 * instead of the core having chosen it earlier
4662 	 */
4663 	if (!hcd->driver->address_device && devnum <= 1)
4664 		return -EINVAL;
4665 	if (udev->state == USB_STATE_ADDRESS)
4666 		return 0;
4667 	if (udev->state != USB_STATE_DEFAULT)
4668 		return -EINVAL;
4669 	if (hcd->driver->address_device)
4670 		retval = hcd->driver->address_device(hcd, udev);
4671 	else
4672 		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4673 				USB_REQ_SET_ADDRESS, 0, devnum, 0,
4674 				NULL, 0, USB_CTRL_SET_TIMEOUT);
4675 	if (retval == 0) {
4676 		update_devnum(udev, devnum);
4677 		/* Device now using proper address. */
4678 		usb_set_device_state(udev, USB_STATE_ADDRESS);
4679 		usb_ep0_reinit(udev);
4680 	}
4681 	return retval;
4682 }
4683 
4684 /*
4685  * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4686  * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4687  * enabled.
4688  *
4689  * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4690  * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4691  * support bit in the BOS descriptor.
4692  */
hub_set_initial_usb2_lpm_policy(struct usb_device * udev)4693 static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4694 {
4695 	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4696 	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4697 
4698 	if (!udev->usb2_hw_lpm_capable || !udev->bos)
4699 		return;
4700 
4701 	if (hub)
4702 		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4703 
4704 	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4705 			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4706 		udev->usb2_hw_lpm_allowed = 1;
4707 		usb_enable_usb2_hardware_lpm(udev);
4708 	}
4709 }
4710 
hub_enable_device(struct usb_device * udev)4711 static int hub_enable_device(struct usb_device *udev)
4712 {
4713 	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4714 
4715 	if (!hcd->driver->enable_device)
4716 		return 0;
4717 	if (udev->state == USB_STATE_ADDRESS)
4718 		return 0;
4719 	if (udev->state != USB_STATE_DEFAULT)
4720 		return -EINVAL;
4721 
4722 	return hcd->driver->enable_device(hcd, udev);
4723 }
4724 
4725 /*
4726  * Get the bMaxPacketSize0 value during initialization by reading the
4727  * device's device descriptor.  Since we don't already know this value,
4728  * the transfer is unsafe and it ignores I/O errors, only testing for
4729  * reasonable received values.
4730  *
4731  * For "old scheme" initialization, size will be 8 so we read just the
4732  * start of the device descriptor, which should work okay regardless of
4733  * the actual bMaxPacketSize0 value.  For "new scheme" initialization,
4734  * size will be 64 (and buf will point to a sufficiently large buffer),
4735  * which might not be kosher according to the USB spec but it's what
4736  * Windows does and what many devices expect.
4737  *
4738  * Returns: bMaxPacketSize0 or a negative error code.
4739  */
get_bMaxPacketSize0(struct usb_device * udev,struct usb_device_descriptor * buf,int size,bool first_time)4740 static int get_bMaxPacketSize0(struct usb_device *udev,
4741 		struct usb_device_descriptor *buf, int size, bool first_time)
4742 {
4743 	int i, rc;
4744 
4745 	/*
4746 	 * Retry on all errors; some devices are flakey.
4747 	 * 255 is for WUSB devices, we actually need to use
4748 	 * 512 (WUSB1.0[4.8.1]).
4749 	 */
4750 	for (i = 0; i < GET_MAXPACKET0_TRIES; ++i) {
4751 		/* Start with invalid values in case the transfer fails */
4752 		buf->bDescriptorType = buf->bMaxPacketSize0 = 0;
4753 		rc = usb_control_msg(udev, usb_rcvaddr0pipe(),
4754 				USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4755 				USB_DT_DEVICE << 8, 0,
4756 				buf, size,
4757 				initial_descriptor_timeout);
4758 		switch (buf->bMaxPacketSize0) {
4759 		case 8: case 16: case 32: case 64: case 9:
4760 			if (buf->bDescriptorType == USB_DT_DEVICE) {
4761 				rc = buf->bMaxPacketSize0;
4762 				break;
4763 			}
4764 			fallthrough;
4765 		default:
4766 			if (rc >= 0)
4767 				rc = -EPROTO;
4768 			break;
4769 		}
4770 
4771 		/*
4772 		 * Some devices time out if they are powered on
4773 		 * when already connected. They need a second
4774 		 * reset, so return early. But only on the first
4775 		 * attempt, lest we get into a time-out/reset loop.
4776 		 */
4777 		if (rc > 0 || (rc == -ETIMEDOUT && first_time &&
4778 				udev->speed > USB_SPEED_FULL))
4779 			break;
4780 	}
4781 	return rc;
4782 }
4783 
4784 #define GET_DESCRIPTOR_BUFSIZE	64
4785 
4786 /* Reset device, (re)assign address, get device descriptor.
4787  * Device connection must be stable, no more debouncing needed.
4788  * Returns device in USB_STATE_ADDRESS, except on error.
4789  *
4790  * If this is called for an already-existing device (as part of
4791  * usb_reset_and_verify_device), the caller must own the device lock and
4792  * the port lock.  For a newly detected device that is not accessible
4793  * through any global pointers, it's not necessary to lock the device,
4794  * but it is still necessary to lock the port.
4795  *
4796  * For a newly detected device, @dev_descr must be NULL.  The device
4797  * descriptor retrieved from the device will then be stored in
4798  * @udev->descriptor.  For an already existing device, @dev_descr
4799  * must be non-NULL.  The device descriptor will be stored there,
4800  * not in @udev->descriptor, because descriptors for registered
4801  * devices are meant to be immutable.
4802  */
4803 static int
hub_port_init(struct usb_hub * hub,struct usb_device * udev,int port1,int retry_counter,struct usb_device_descriptor * dev_descr)4804 hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4805 		int retry_counter, struct usb_device_descriptor *dev_descr)
4806 {
4807 	struct usb_device	*hdev = hub->hdev;
4808 	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
4809 	struct usb_port		*port_dev = hub->ports[port1 - 1];
4810 	int			retries, operations, retval, i;
4811 	unsigned		delay = HUB_SHORT_RESET_TIME;
4812 	enum usb_device_speed	oldspeed = udev->speed;
4813 	const char		*speed;
4814 	int			devnum = udev->devnum;
4815 	const char		*driver_name;
4816 	bool			do_new_scheme;
4817 	const bool		initial = !dev_descr;
4818 	int			maxp0;
4819 	struct usb_device_descriptor	*buf, *descr;
4820 
4821 	buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4822 	if (!buf)
4823 		return -ENOMEM;
4824 
4825 	/* root hub ports have a slightly longer reset period
4826 	 * (from USB 2.0 spec, section 7.1.7.5)
4827 	 */
4828 	if (!hdev->parent) {
4829 		delay = HUB_ROOT_RESET_TIME;
4830 		if (port1 == hdev->bus->otg_port)
4831 			hdev->bus->b_hnp_enable = 0;
4832 	}
4833 
4834 	/* Some low speed devices have problems with the quick delay, so */
4835 	/*  be a bit pessimistic with those devices. RHbug #23670 */
4836 	if (oldspeed == USB_SPEED_LOW)
4837 		delay = HUB_LONG_RESET_TIME;
4838 
4839 	/* Reset the device; full speed may morph to high speed */
4840 	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4841 	retval = hub_port_reset(hub, port1, udev, delay, false);
4842 	if (retval < 0)		/* error or disconnect */
4843 		goto fail;
4844 	/* success, speed is known */
4845 
4846 	retval = -ENODEV;
4847 
4848 	/* Don't allow speed changes at reset, except usb 3.0 to faster */
4849 	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4850 	    !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4851 		dev_dbg(&udev->dev, "device reset changed speed!\n");
4852 		goto fail;
4853 	}
4854 	oldspeed = udev->speed;
4855 
4856 	if (initial) {
4857 		/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4858 		 * it's fixed size except for full speed devices.
4859 		 */
4860 		switch (udev->speed) {
4861 		case USB_SPEED_SUPER_PLUS:
4862 		case USB_SPEED_SUPER:
4863 			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4864 			break;
4865 		case USB_SPEED_HIGH:		/* fixed at 64 */
4866 			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4867 			break;
4868 		case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
4869 			/* to determine the ep0 maxpacket size, try to read
4870 			 * the device descriptor to get bMaxPacketSize0 and
4871 			 * then correct our initial guess.
4872 			 */
4873 			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4874 			break;
4875 		case USB_SPEED_LOW:		/* fixed at 8 */
4876 			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4877 			break;
4878 		default:
4879 			goto fail;
4880 		}
4881 	}
4882 
4883 	speed = usb_speed_string(udev->speed);
4884 
4885 	/*
4886 	 * The controller driver may be NULL if the controller device
4887 	 * is the middle device between platform device and roothub.
4888 	 * This middle device may not need a device driver due to
4889 	 * all hardware control can be at platform device driver, this
4890 	 * platform device is usually a dual-role USB controller device.
4891 	 */
4892 	if (udev->bus->controller->driver)
4893 		driver_name = udev->bus->controller->driver->name;
4894 	else
4895 		driver_name = udev->bus->sysdev->driver->name;
4896 
4897 	if (udev->speed < USB_SPEED_SUPER)
4898 		dev_info(&udev->dev,
4899 				"%s %s USB device number %d using %s\n",
4900 				(initial ? "new" : "reset"), speed,
4901 				devnum, driver_name);
4902 
4903 	if (initial) {
4904 		/* Set up TT records, if needed  */
4905 		if (hdev->tt) {
4906 			udev->tt = hdev->tt;
4907 			udev->ttport = hdev->ttport;
4908 		} else if (udev->speed != USB_SPEED_HIGH
4909 				&& hdev->speed == USB_SPEED_HIGH) {
4910 			if (!hub->tt.hub) {
4911 				dev_err(&udev->dev, "parent hub has no TT\n");
4912 				retval = -EINVAL;
4913 				goto fail;
4914 			}
4915 			udev->tt = &hub->tt;
4916 			udev->ttport = port1;
4917 		}
4918 	}
4919 
4920 	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4921 	 * Because device hardware and firmware is sometimes buggy in
4922 	 * this area, and this is how Linux has done it for ages.
4923 	 * Change it cautiously.
4924 	 *
4925 	 * NOTE:  If use_new_scheme() is true we will start by issuing
4926 	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4927 	 * so it may help with some non-standards-compliant devices.
4928 	 * Otherwise we start with SET_ADDRESS and then try to read the
4929 	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
4930 	 * value.
4931 	 */
4932 	do_new_scheme = use_new_scheme(udev, retry_counter, port_dev);
4933 
4934 	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4935 		if (hub_port_stop_enumerate(hub, port1, retries)) {
4936 			retval = -ENODEV;
4937 			break;
4938 		}
4939 
4940 		if (do_new_scheme) {
4941 			retval = hub_enable_device(udev);
4942 			if (retval < 0) {
4943 				dev_err(&udev->dev,
4944 					"hub failed to enable device, error %d\n",
4945 					retval);
4946 				goto fail;
4947 			}
4948 
4949 			maxp0 = get_bMaxPacketSize0(udev, buf,
4950 					GET_DESCRIPTOR_BUFSIZE, retries == 0);
4951 			if (maxp0 > 0 && !initial &&
4952 					maxp0 != udev->descriptor.bMaxPacketSize0) {
4953 				dev_err(&udev->dev, "device reset changed ep0 maxpacket size!\n");
4954 				retval = -ENODEV;
4955 				goto fail;
4956 			}
4957 
4958 			retval = hub_port_reset(hub, port1, udev, delay, false);
4959 			if (retval < 0)		/* error or disconnect */
4960 				goto fail;
4961 			if (oldspeed != udev->speed) {
4962 				dev_dbg(&udev->dev,
4963 					"device reset changed speed!\n");
4964 				retval = -ENODEV;
4965 				goto fail;
4966 			}
4967 			if (maxp0 < 0) {
4968 				if (maxp0 != -ENODEV)
4969 					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
4970 							maxp0);
4971 				retval = maxp0;
4972 				continue;
4973 			}
4974 		}
4975 
4976 		for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
4977 			retval = hub_set_address(udev, devnum);
4978 			if (retval >= 0)
4979 				break;
4980 			msleep(200);
4981 		}
4982 		if (retval < 0) {
4983 			if (retval != -ENODEV)
4984 				dev_err(&udev->dev, "device not accepting address %d, error %d\n",
4985 						devnum, retval);
4986 			goto fail;
4987 		}
4988 		if (udev->speed >= USB_SPEED_SUPER) {
4989 			devnum = udev->devnum;
4990 			dev_info(&udev->dev,
4991 					"%s SuperSpeed%s%s USB device number %d using %s\n",
4992 					(udev->config) ? "reset" : "new",
4993 				 (udev->speed == USB_SPEED_SUPER_PLUS) ?
4994 						" Plus" : "",
4995 				 (udev->ssp_rate == USB_SSP_GEN_2x2) ?
4996 						" Gen 2x2" :
4997 				 (udev->ssp_rate == USB_SSP_GEN_2x1) ?
4998 						" Gen 2x1" :
4999 				 (udev->ssp_rate == USB_SSP_GEN_1x2) ?
5000 						" Gen 1x2" : "",
5001 				 devnum, driver_name);
5002 		}
5003 
5004 		/*
5005 		 * cope with hardware quirkiness:
5006 		 *  - let SET_ADDRESS settle, some device hardware wants it
5007 		 *  - read ep0 maxpacket even for high and low speed,
5008 		 */
5009 		msleep(10);
5010 
5011 		if (do_new_scheme)
5012 			break;
5013 
5014 		maxp0 = get_bMaxPacketSize0(udev, buf, 8, retries == 0);
5015 		if (maxp0 < 0) {
5016 			retval = maxp0;
5017 			if (retval != -ENODEV)
5018 				dev_err(&udev->dev,
5019 					"device descriptor read/8, error %d\n",
5020 					retval);
5021 		} else {
5022 			u32 delay;
5023 
5024 			if (!initial && maxp0 != udev->descriptor.bMaxPacketSize0) {
5025 				dev_err(&udev->dev, "device reset changed ep0 maxpacket size!\n");
5026 				retval = -ENODEV;
5027 				goto fail;
5028 			}
5029 
5030 			delay = udev->parent->hub_delay;
5031 			udev->hub_delay = min_t(u32, delay,
5032 						USB_TP_TRANSMISSION_DELAY_MAX);
5033 			retval = usb_set_isoch_delay(udev);
5034 			if (retval) {
5035 				dev_dbg(&udev->dev,
5036 					"Failed set isoch delay, error %d\n",
5037 					retval);
5038 				retval = 0;
5039 			}
5040 			break;
5041 		}
5042 	}
5043 	if (retval)
5044 		goto fail;
5045 
5046 	/*
5047 	 * Check the ep0 maxpacket guess and correct it if necessary.
5048 	 * maxp0 is the value stored in the device descriptor;
5049 	 * i is the value it encodes (logarithmic for SuperSpeed or greater).
5050 	 */
5051 	i = maxp0;
5052 	if (udev->speed >= USB_SPEED_SUPER) {
5053 		if (maxp0 <= 16)
5054 			i = 1 << maxp0;
5055 		else
5056 			i = 0;		/* Invalid */
5057 	}
5058 	if (usb_endpoint_maxp(&udev->ep0.desc) == i) {
5059 		;	/* Initial ep0 maxpacket guess is right */
5060 	} else if ((udev->speed == USB_SPEED_FULL ||
5061 				udev->speed == USB_SPEED_HIGH) &&
5062 			(i == 8 || i == 16 || i == 32 || i == 64)) {
5063 		/* Initial guess is wrong; use the descriptor's value */
5064 		if (udev->speed == USB_SPEED_FULL)
5065 			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
5066 		else
5067 			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
5068 		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
5069 		usb_ep0_reinit(udev);
5070 	} else {
5071 		/* Initial guess is wrong and descriptor's value is invalid */
5072 		dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", maxp0);
5073 		retval = -EMSGSIZE;
5074 		goto fail;
5075 	}
5076 
5077 	descr = usb_get_device_descriptor(udev);
5078 	if (IS_ERR(descr)) {
5079 		retval = PTR_ERR(descr);
5080 		if (retval != -ENODEV)
5081 			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
5082 					retval);
5083 		goto fail;
5084 	}
5085 	if (initial)
5086 		udev->descriptor = *descr;
5087 	else
5088 		*dev_descr = *descr;
5089 	kfree(descr);
5090 
5091 	/*
5092 	 * Some superspeed devices have finished the link training process
5093 	 * and attached to a superspeed hub port, but the device descriptor
5094 	 * got from those devices show they aren't superspeed devices. Warm
5095 	 * reset the port attached by the devices can fix them.
5096 	 */
5097 	if ((udev->speed >= USB_SPEED_SUPER) &&
5098 			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
5099 		dev_err(&udev->dev, "got a wrong device descriptor, warm reset device\n");
5100 		hub_port_reset(hub, port1, udev, HUB_BH_RESET_TIME, true);
5101 		retval = -EINVAL;
5102 		goto fail;
5103 	}
5104 
5105 	usb_detect_quirks(udev);
5106 
5107 	if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
5108 		retval = usb_get_bos_descriptor(udev);
5109 		if (!retval) {
5110 			udev->lpm_capable = usb_device_supports_lpm(udev);
5111 			udev->lpm_disable_count = 1;
5112 			usb_set_lpm_parameters(udev);
5113 			usb_req_set_sel(udev);
5114 		}
5115 	}
5116 
5117 	retval = 0;
5118 	/* notify HCD that we have a device connected and addressed */
5119 	if (hcd->driver->update_device)
5120 		hcd->driver->update_device(hcd, udev);
5121 	hub_set_initial_usb2_lpm_policy(udev);
5122 fail:
5123 	if (retval) {
5124 		hub_port_disable(hub, port1, 0);
5125 		update_devnum(udev, devnum);	/* for disconnect processing */
5126 	}
5127 	kfree(buf);
5128 	return retval;
5129 }
5130 
5131 static void
check_highspeed(struct usb_hub * hub,struct usb_device * udev,int port1)5132 check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
5133 {
5134 	struct usb_qualifier_descriptor	*qual;
5135 	int				status;
5136 
5137 	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
5138 		return;
5139 
5140 	qual = kmalloc(sizeof *qual, GFP_KERNEL);
5141 	if (qual == NULL)
5142 		return;
5143 
5144 	status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
5145 			qual, sizeof *qual);
5146 	if (status == sizeof *qual) {
5147 		dev_info(&udev->dev, "not running at top speed; "
5148 			"connect to a high speed hub\n");
5149 		/* hub LEDs are probably harder to miss than syslog */
5150 		if (hub->has_indicators) {
5151 			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
5152 			queue_delayed_work(system_power_efficient_wq,
5153 					&hub->leds, 0);
5154 		}
5155 	}
5156 	kfree(qual);
5157 }
5158 
5159 static unsigned
hub_power_remaining(struct usb_hub * hub)5160 hub_power_remaining(struct usb_hub *hub)
5161 {
5162 	struct usb_device *hdev = hub->hdev;
5163 	int remaining;
5164 	int port1;
5165 
5166 	if (!hub->limited_power)
5167 		return 0;
5168 
5169 	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
5170 	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
5171 		struct usb_port *port_dev = hub->ports[port1 - 1];
5172 		struct usb_device *udev = port_dev->child;
5173 		unsigned unit_load;
5174 		int delta;
5175 
5176 		if (!udev)
5177 			continue;
5178 		if (hub_is_superspeed(udev))
5179 			unit_load = 150;
5180 		else
5181 			unit_load = 100;
5182 
5183 		/*
5184 		 * Unconfigured devices may not use more than one unit load,
5185 		 * or 8mA for OTG ports
5186 		 */
5187 		if (udev->actconfig)
5188 			delta = usb_get_max_power(udev, udev->actconfig);
5189 		else if (port1 != udev->bus->otg_port || hdev->parent)
5190 			delta = unit_load;
5191 		else
5192 			delta = 8;
5193 		if (delta > hub->mA_per_port)
5194 			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
5195 					delta, hub->mA_per_port);
5196 		remaining -= delta;
5197 	}
5198 	if (remaining < 0) {
5199 		dev_warn(hub->intfdev, "%dmA over power budget!\n",
5200 			-remaining);
5201 		remaining = 0;
5202 	}
5203 	return remaining;
5204 }
5205 
5206 
descriptors_changed(struct usb_device * udev,struct usb_device_descriptor * new_device_descriptor,struct usb_host_bos * old_bos)5207 static int descriptors_changed(struct usb_device *udev,
5208 		struct usb_device_descriptor *new_device_descriptor,
5209 		struct usb_host_bos *old_bos)
5210 {
5211 	int		changed = 0;
5212 	unsigned	index;
5213 	unsigned	serial_len = 0;
5214 	unsigned	len;
5215 	unsigned	old_length;
5216 	int		length;
5217 	char		*buf;
5218 
5219 	if (memcmp(&udev->descriptor, new_device_descriptor,
5220 			sizeof(*new_device_descriptor)) != 0)
5221 		return 1;
5222 
5223 	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
5224 		return 1;
5225 	if (udev->bos) {
5226 		len = le16_to_cpu(udev->bos->desc->wTotalLength);
5227 		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5228 			return 1;
5229 		if (memcmp(udev->bos->desc, old_bos->desc, len))
5230 			return 1;
5231 	}
5232 
5233 	/* Since the idVendor, idProduct, and bcdDevice values in the
5234 	 * device descriptor haven't changed, we will assume the
5235 	 * Manufacturer and Product strings haven't changed either.
5236 	 * But the SerialNumber string could be different (e.g., a
5237 	 * different flash card of the same brand).
5238 	 */
5239 	if (udev->serial)
5240 		serial_len = strlen(udev->serial) + 1;
5241 
5242 	len = serial_len;
5243 	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5244 		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5245 		len = max(len, old_length);
5246 	}
5247 
5248 	buf = kmalloc(len, GFP_NOIO);
5249 	if (!buf)
5250 		/* assume the worst */
5251 		return 1;
5252 
5253 	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5254 		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5255 		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5256 				old_length);
5257 		if (length != old_length) {
5258 			dev_dbg(&udev->dev, "config index %d, error %d\n",
5259 					index, length);
5260 			changed = 1;
5261 			break;
5262 		}
5263 		if (memcmp(buf, udev->rawdescriptors[index], old_length)
5264 				!= 0) {
5265 			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5266 				index,
5267 				((struct usb_config_descriptor *) buf)->
5268 					bConfigurationValue);
5269 			changed = 1;
5270 			break;
5271 		}
5272 	}
5273 
5274 	if (!changed && serial_len) {
5275 		length = usb_string(udev, udev->descriptor.iSerialNumber,
5276 				buf, serial_len);
5277 		if (length + 1 != serial_len) {
5278 			dev_dbg(&udev->dev, "serial string error %d\n",
5279 					length);
5280 			changed = 1;
5281 		} else if (memcmp(buf, udev->serial, length) != 0) {
5282 			dev_dbg(&udev->dev, "serial string changed\n");
5283 			changed = 1;
5284 		}
5285 	}
5286 
5287 	kfree(buf);
5288 	return changed;
5289 }
5290 
hub_port_connect(struct usb_hub * hub,int port1,u16 portstatus,u16 portchange)5291 static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
5292 		u16 portchange)
5293 {
5294 	int status = -ENODEV;
5295 	int i;
5296 	unsigned unit_load;
5297 	struct usb_device *hdev = hub->hdev;
5298 	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
5299 	struct usb_port *port_dev = hub->ports[port1 - 1];
5300 	struct usb_device *udev = port_dev->child;
5301 	static int unreliable_port = -1;
5302 	bool retry_locked;
5303 
5304 	/* Disconnect any existing devices under this port */
5305 	if (udev) {
5306 		if (hcd->usb_phy && !hdev->parent)
5307 			usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
5308 		usb_disconnect(&port_dev->child);
5309 	}
5310 
5311 	/* We can forget about a "removed" device when there's a physical
5312 	 * disconnect or the connect status changes.
5313 	 */
5314 	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5315 			(portchange & USB_PORT_STAT_C_CONNECTION))
5316 		clear_bit(port1, hub->removed_bits);
5317 
5318 	if (portchange & (USB_PORT_STAT_C_CONNECTION |
5319 				USB_PORT_STAT_C_ENABLE)) {
5320 		status = hub_port_debounce_be_stable(hub, port1);
5321 		if (status < 0) {
5322 			if (status != -ENODEV &&
5323 				port1 != unreliable_port &&
5324 				printk_ratelimit())
5325 				dev_err(&port_dev->dev, "connect-debounce failed\n");
5326 			portstatus &= ~USB_PORT_STAT_CONNECTION;
5327 			unreliable_port = port1;
5328 		} else {
5329 			portstatus = status;
5330 		}
5331 	}
5332 
5333 	/* Return now if debouncing failed or nothing is connected or
5334 	 * the device was "removed".
5335 	 */
5336 	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5337 			test_bit(port1, hub->removed_bits)) {
5338 
5339 		/*
5340 		 * maybe switch power back on (e.g. root hub was reset)
5341 		 * but only if the port isn't owned by someone else.
5342 		 */
5343 		if (hub_is_port_power_switchable(hub)
5344 				&& !usb_port_is_power_on(hub, portstatus)
5345 				&& !port_dev->port_owner)
5346 			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
5347 
5348 		if (portstatus & USB_PORT_STAT_ENABLE)
5349 			goto done;
5350 		return;
5351 	}
5352 	if (hub_is_superspeed(hub->hdev))
5353 		unit_load = 150;
5354 	else
5355 		unit_load = 100;
5356 
5357 	status = 0;
5358 
5359 	for (i = 0; i < PORT_INIT_TRIES; i++) {
5360 		if (hub_port_stop_enumerate(hub, port1, i)) {
5361 			status = -ENODEV;
5362 			break;
5363 		}
5364 
5365 		usb_lock_port(port_dev);
5366 		mutex_lock(hcd->address0_mutex);
5367 		retry_locked = true;
5368 		/* reallocate for each attempt, since references
5369 		 * to the previous one can escape in various ways
5370 		 */
5371 		udev = usb_alloc_dev(hdev, hdev->bus, port1);
5372 		if (!udev) {
5373 			dev_err(&port_dev->dev,
5374 					"couldn't allocate usb_device\n");
5375 			mutex_unlock(hcd->address0_mutex);
5376 			usb_unlock_port(port_dev);
5377 			goto done;
5378 		}
5379 
5380 		usb_set_device_state(udev, USB_STATE_POWERED);
5381 		udev->bus_mA = hub->mA_per_port;
5382 		udev->level = hdev->level + 1;
5383 
5384 		/* Devices connected to SuperSpeed hubs are USB 3.0 or later */
5385 		if (hub_is_superspeed(hub->hdev))
5386 			udev->speed = USB_SPEED_SUPER;
5387 		else
5388 			udev->speed = USB_SPEED_UNKNOWN;
5389 
5390 		choose_devnum(udev);
5391 		if (udev->devnum <= 0) {
5392 			status = -ENOTCONN;	/* Don't retry */
5393 			goto loop;
5394 		}
5395 
5396 		/* reset (non-USB 3.0 devices) and get descriptor */
5397 		status = hub_port_init(hub, udev, port1, i, NULL);
5398 		if (status < 0)
5399 			goto loop;
5400 
5401 		mutex_unlock(hcd->address0_mutex);
5402 		usb_unlock_port(port_dev);
5403 		retry_locked = false;
5404 
5405 		if (udev->quirks & USB_QUIRK_DELAY_INIT)
5406 			msleep(2000);
5407 
5408 		/* consecutive bus-powered hubs aren't reliable; they can
5409 		 * violate the voltage drop budget.  if the new child has
5410 		 * a "powered" LED, users should notice we didn't enable it
5411 		 * (without reading syslog), even without per-port LEDs
5412 		 * on the parent.
5413 		 */
5414 		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
5415 				&& udev->bus_mA <= unit_load) {
5416 			u16	devstat;
5417 
5418 			status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
5419 					&devstat);
5420 			if (status) {
5421 				dev_dbg(&udev->dev, "get status %d ?\n", status);
5422 				goto loop_disable;
5423 			}
5424 			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
5425 				dev_err(&udev->dev,
5426 					"can't connect bus-powered hub "
5427 					"to this port\n");
5428 				if (hub->has_indicators) {
5429 					hub->indicator[port1-1] =
5430 						INDICATOR_AMBER_BLINK;
5431 					queue_delayed_work(
5432 						system_power_efficient_wq,
5433 						&hub->leds, 0);
5434 				}
5435 				status = -ENOTCONN;	/* Don't retry */
5436 				goto loop_disable;
5437 			}
5438 		}
5439 
5440 		/* check for devices running slower than they could */
5441 		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
5442 				&& udev->speed == USB_SPEED_FULL
5443 				&& highspeed_hubs != 0)
5444 			check_highspeed(hub, udev, port1);
5445 
5446 		/* Store the parent's children[] pointer.  At this point
5447 		 * udev becomes globally accessible, although presumably
5448 		 * no one will look at it until hdev is unlocked.
5449 		 */
5450 		status = 0;
5451 
5452 		mutex_lock(&usb_port_peer_mutex);
5453 
5454 		/* We mustn't add new devices if the parent hub has
5455 		 * been disconnected; we would race with the
5456 		 * recursively_mark_NOTATTACHED() routine.
5457 		 */
5458 		spin_lock_irq(&device_state_lock);
5459 		if (hdev->state == USB_STATE_NOTATTACHED)
5460 			status = -ENOTCONN;
5461 		else
5462 			port_dev->child = udev;
5463 		spin_unlock_irq(&device_state_lock);
5464 		mutex_unlock(&usb_port_peer_mutex);
5465 
5466 		/* Run it through the hoops (find a driver, etc) */
5467 		if (!status) {
5468 			status = usb_new_device(udev);
5469 			if (status) {
5470 				mutex_lock(&usb_port_peer_mutex);
5471 				spin_lock_irq(&device_state_lock);
5472 				port_dev->child = NULL;
5473 				spin_unlock_irq(&device_state_lock);
5474 				mutex_unlock(&usb_port_peer_mutex);
5475 			} else {
5476 				if (hcd->usb_phy && !hdev->parent)
5477 					usb_phy_notify_connect(hcd->usb_phy,
5478 							udev->speed);
5479 			}
5480 		}
5481 
5482 		if (status)
5483 			goto loop_disable;
5484 
5485 		status = hub_power_remaining(hub);
5486 		if (status)
5487 			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
5488 
5489 		return;
5490 
5491 loop_disable:
5492 		hub_port_disable(hub, port1, 1);
5493 loop:
5494 		usb_ep0_reinit(udev);
5495 		release_devnum(udev);
5496 		hub_free_dev(udev);
5497 		if (retry_locked) {
5498 			mutex_unlock(hcd->address0_mutex);
5499 			usb_unlock_port(port_dev);
5500 		}
5501 		usb_put_dev(udev);
5502 		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
5503 			break;
5504 
5505 		/* When halfway through our retry count, power-cycle the port */
5506 		if (i == (PORT_INIT_TRIES - 1) / 2) {
5507 			dev_info(&port_dev->dev, "attempt power cycle\n");
5508 			usb_hub_set_port_power(hdev, hub, port1, false);
5509 			msleep(2 * hub_power_on_good_delay(hub));
5510 			usb_hub_set_port_power(hdev, hub, port1, true);
5511 			msleep(hub_power_on_good_delay(hub));
5512 		}
5513 	}
5514 	if (hub->hdev->parent ||
5515 			!hcd->driver->port_handed_over ||
5516 			!(hcd->driver->port_handed_over)(hcd, port1)) {
5517 		if (status != -ENOTCONN && status != -ENODEV)
5518 			dev_err(&port_dev->dev,
5519 					"unable to enumerate USB device\n");
5520 	}
5521 
5522 done:
5523 	hub_port_disable(hub, port1, 1);
5524 	if (hcd->driver->relinquish_port && !hub->hdev->parent) {
5525 		if (status != -ENOTCONN && status != -ENODEV)
5526 			hcd->driver->relinquish_port(hcd, port1);
5527 	}
5528 }
5529 
5530 /* Handle physical or logical connection change events.
5531  * This routine is called when:
5532  *	a port connection-change occurs;
5533  *	a port enable-change occurs (often caused by EMI);
5534  *	usb_reset_and_verify_device() encounters changed descriptors (as from
5535  *		a firmware download)
5536  * caller already locked the hub
5537  */
hub_port_connect_change(struct usb_hub * hub,int port1,u16 portstatus,u16 portchange)5538 static void hub_port_connect_change(struct usb_hub *hub, int port1,
5539 					u16 portstatus, u16 portchange)
5540 		__must_hold(&port_dev->status_lock)
5541 {
5542 	struct usb_port *port_dev = hub->ports[port1 - 1];
5543 	struct usb_device *udev = port_dev->child;
5544 	struct usb_device_descriptor *descr;
5545 	int status = -ENODEV;
5546 
5547 	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
5548 			portchange, portspeed(hub, portstatus));
5549 
5550 	if (hub->has_indicators) {
5551 		set_port_led(hub, port1, HUB_LED_AUTO);
5552 		hub->indicator[port1-1] = INDICATOR_AUTO;
5553 	}
5554 
5555 #ifdef	CONFIG_USB_OTG
5556 	/* during HNP, don't repeat the debounce */
5557 	if (hub->hdev->bus->is_b_host)
5558 		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
5559 				USB_PORT_STAT_C_ENABLE);
5560 #endif
5561 
5562 	/* Try to resuscitate an existing device */
5563 	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
5564 			udev->state != USB_STATE_NOTATTACHED) {
5565 		if (portstatus & USB_PORT_STAT_ENABLE) {
5566 			/*
5567 			 * USB-3 connections are initialized automatically by
5568 			 * the hostcontroller hardware. Therefore check for
5569 			 * changed device descriptors before resuscitating the
5570 			 * device.
5571 			 */
5572 			descr = usb_get_device_descriptor(udev);
5573 			if (IS_ERR(descr)) {
5574 				dev_dbg(&udev->dev,
5575 						"can't read device descriptor %ld\n",
5576 						PTR_ERR(descr));
5577 			} else {
5578 				if (descriptors_changed(udev, descr,
5579 						udev->bos)) {
5580 					dev_dbg(&udev->dev,
5581 							"device descriptor has changed\n");
5582 				} else {
5583 					status = 0; /* Nothing to do */
5584 				}
5585 				kfree(descr);
5586 			}
5587 #ifdef CONFIG_PM
5588 		} else if (udev->state == USB_STATE_SUSPENDED &&
5589 				udev->persist_enabled) {
5590 			/* For a suspended device, treat this as a
5591 			 * remote wakeup event.
5592 			 */
5593 			usb_unlock_port(port_dev);
5594 			status = usb_remote_wakeup(udev);
5595 			usb_lock_port(port_dev);
5596 #endif
5597 		} else {
5598 			/* Don't resuscitate */;
5599 		}
5600 	}
5601 	clear_bit(port1, hub->change_bits);
5602 
5603 	/* successfully revalidated the connection */
5604 	if (status == 0)
5605 		return;
5606 
5607 	usb_unlock_port(port_dev);
5608 	hub_port_connect(hub, port1, portstatus, portchange);
5609 	usb_lock_port(port_dev);
5610 }
5611 
5612 /* Handle notifying userspace about hub over-current events */
port_over_current_notify(struct usb_port * port_dev)5613 static void port_over_current_notify(struct usb_port *port_dev)
5614 {
5615 	char *envp[3] = { NULL, NULL, NULL };
5616 	struct device *hub_dev;
5617 	char *port_dev_path;
5618 
5619 	sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
5620 
5621 	hub_dev = port_dev->dev.parent;
5622 
5623 	if (!hub_dev)
5624 		return;
5625 
5626 	port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
5627 	if (!port_dev_path)
5628 		return;
5629 
5630 	envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
5631 	if (!envp[0])
5632 		goto exit;
5633 
5634 	envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
5635 			port_dev->over_current_count);
5636 	if (!envp[1])
5637 		goto exit;
5638 
5639 	kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
5640 
5641 exit:
5642 	kfree(envp[1]);
5643 	kfree(envp[0]);
5644 	kfree(port_dev_path);
5645 }
5646 
port_event(struct usb_hub * hub,int port1)5647 static void port_event(struct usb_hub *hub, int port1)
5648 		__must_hold(&port_dev->status_lock)
5649 {
5650 	int connect_change;
5651 	struct usb_port *port_dev = hub->ports[port1 - 1];
5652 	struct usb_device *udev = port_dev->child;
5653 	struct usb_device *hdev = hub->hdev;
5654 	u16 portstatus, portchange;
5655 	int i = 0;
5656 
5657 	connect_change = test_bit(port1, hub->change_bits);
5658 	clear_bit(port1, hub->event_bits);
5659 	clear_bit(port1, hub->wakeup_bits);
5660 
5661 	if (usb_hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5662 		return;
5663 
5664 	if (portchange & USB_PORT_STAT_C_CONNECTION) {
5665 		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5666 		connect_change = 1;
5667 	}
5668 
5669 	if (portchange & USB_PORT_STAT_C_ENABLE) {
5670 		if (!connect_change)
5671 			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5672 					portstatus);
5673 		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5674 
5675 		/*
5676 		 * EM interference sometimes causes badly shielded USB devices
5677 		 * to be shutdown by the hub, this hack enables them again.
5678 		 * Works at least with mouse driver.
5679 		 */
5680 		if (!(portstatus & USB_PORT_STAT_ENABLE)
5681 		    && !connect_change && udev) {
5682 			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5683 			connect_change = 1;
5684 		}
5685 	}
5686 
5687 	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5688 		u16 status = 0, unused;
5689 		port_dev->over_current_count++;
5690 		port_over_current_notify(port_dev);
5691 
5692 		dev_dbg(&port_dev->dev, "over-current change #%u\n",
5693 			port_dev->over_current_count);
5694 		usb_clear_port_feature(hdev, port1,
5695 				USB_PORT_FEAT_C_OVER_CURRENT);
5696 		msleep(100);	/* Cool down */
5697 		hub_power_on(hub, true);
5698 		usb_hub_port_status(hub, port1, &status, &unused);
5699 		if (status & USB_PORT_STAT_OVERCURRENT)
5700 			dev_err(&port_dev->dev, "over-current condition\n");
5701 	}
5702 
5703 	if (portchange & USB_PORT_STAT_C_RESET) {
5704 		dev_dbg(&port_dev->dev, "reset change\n");
5705 		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5706 	}
5707 	if ((portchange & USB_PORT_STAT_C_BH_RESET)
5708 	    && hub_is_superspeed(hdev)) {
5709 		dev_dbg(&port_dev->dev, "warm reset change\n");
5710 		usb_clear_port_feature(hdev, port1,
5711 				USB_PORT_FEAT_C_BH_PORT_RESET);
5712 	}
5713 	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5714 		dev_dbg(&port_dev->dev, "link state change\n");
5715 		usb_clear_port_feature(hdev, port1,
5716 				USB_PORT_FEAT_C_PORT_LINK_STATE);
5717 	}
5718 	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5719 		dev_warn(&port_dev->dev, "config error\n");
5720 		usb_clear_port_feature(hdev, port1,
5721 				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5722 	}
5723 
5724 	/* skip port actions that require the port to be powered on */
5725 	if (!pm_runtime_active(&port_dev->dev))
5726 		return;
5727 
5728 	/* skip port actions if ignore_event and early_stop are true */
5729 	if (port_dev->ignore_event && port_dev->early_stop)
5730 		return;
5731 
5732 	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5733 		connect_change = 1;
5734 
5735 	/*
5736 	 * Avoid trying to recover a USB3 SS.Inactive port with a warm reset if
5737 	 * the device was disconnected. A 12ms disconnect detect timer in
5738 	 * SS.Inactive state transitions the port to RxDetect automatically.
5739 	 * SS.Inactive link error state is common during device disconnect.
5740 	 */
5741 	while (hub_port_warm_reset_required(hub, port1, portstatus)) {
5742 		if ((i++ < DETECT_DISCONNECT_TRIES) && udev) {
5743 			u16 unused;
5744 
5745 			msleep(20);
5746 			usb_hub_port_status(hub, port1, &portstatus, &unused);
5747 			dev_dbg(&port_dev->dev, "Wait for inactive link disconnect detect\n");
5748 			continue;
5749 		} else if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5750 				|| udev->state == USB_STATE_NOTATTACHED) {
5751 			dev_dbg(&port_dev->dev, "do warm reset, port only\n");
5752 			if (hub_port_reset(hub, port1, NULL,
5753 					HUB_BH_RESET_TIME, true) < 0)
5754 				hub_port_disable(hub, port1, 1);
5755 		} else {
5756 			dev_dbg(&port_dev->dev, "do warm reset, full device\n");
5757 			usb_unlock_port(port_dev);
5758 			usb_lock_device(udev);
5759 			usb_reset_device(udev);
5760 			usb_unlock_device(udev);
5761 			usb_lock_port(port_dev);
5762 			connect_change = 0;
5763 		}
5764 		break;
5765 	}
5766 
5767 	if (connect_change)
5768 		hub_port_connect_change(hub, port1, portstatus, portchange);
5769 }
5770 
hub_event(struct work_struct * work)5771 static void hub_event(struct work_struct *work)
5772 {
5773 	struct usb_device *hdev;
5774 	struct usb_interface *intf;
5775 	struct usb_hub *hub;
5776 	struct device *hub_dev;
5777 	u16 hubstatus;
5778 	u16 hubchange;
5779 	int i, ret;
5780 
5781 	hub = container_of(work, struct usb_hub, events);
5782 	hdev = hub->hdev;
5783 	hub_dev = hub->intfdev;
5784 	intf = to_usb_interface(hub_dev);
5785 
5786 	kcov_remote_start_usb((u64)hdev->bus->busnum);
5787 
5788 	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5789 			hdev->state, hdev->maxchild,
5790 			/* NOTE: expects max 15 ports... */
5791 			(u16) hub->change_bits[0],
5792 			(u16) hub->event_bits[0]);
5793 
5794 	/* Lock the device, then check to see if we were
5795 	 * disconnected while waiting for the lock to succeed. */
5796 	usb_lock_device(hdev);
5797 	if (unlikely(hub->disconnected))
5798 		goto out_hdev_lock;
5799 
5800 	/* If the hub has died, clean up after it */
5801 	if (hdev->state == USB_STATE_NOTATTACHED) {
5802 		hub->error = -ENODEV;
5803 		hub_quiesce(hub, HUB_DISCONNECT);
5804 		goto out_hdev_lock;
5805 	}
5806 
5807 	/* Autoresume */
5808 	ret = usb_autopm_get_interface(intf);
5809 	if (ret) {
5810 		dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5811 		goto out_hdev_lock;
5812 	}
5813 
5814 	/* If this is an inactive hub, do nothing */
5815 	if (hub->quiescing)
5816 		goto out_autopm;
5817 
5818 	if (hub->error) {
5819 		dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5820 
5821 		ret = usb_reset_device(hdev);
5822 		if (ret) {
5823 			dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5824 			goto out_autopm;
5825 		}
5826 
5827 		hub->nerrors = 0;
5828 		hub->error = 0;
5829 	}
5830 
5831 	/* deal with port status changes */
5832 	for (i = 1; i <= hdev->maxchild; i++) {
5833 		struct usb_port *port_dev = hub->ports[i - 1];
5834 
5835 		if (test_bit(i, hub->event_bits)
5836 				|| test_bit(i, hub->change_bits)
5837 				|| test_bit(i, hub->wakeup_bits)) {
5838 			/*
5839 			 * The get_noresume and barrier ensure that if
5840 			 * the port was in the process of resuming, we
5841 			 * flush that work and keep the port active for
5842 			 * the duration of the port_event().  However,
5843 			 * if the port is runtime pm suspended
5844 			 * (powered-off), we leave it in that state, run
5845 			 * an abbreviated port_event(), and move on.
5846 			 */
5847 			pm_runtime_get_noresume(&port_dev->dev);
5848 			pm_runtime_barrier(&port_dev->dev);
5849 			usb_lock_port(port_dev);
5850 			port_event(hub, i);
5851 			usb_unlock_port(port_dev);
5852 			pm_runtime_put_sync(&port_dev->dev);
5853 		}
5854 	}
5855 
5856 	/* deal with hub status changes */
5857 	if (test_and_clear_bit(0, hub->event_bits) == 0)
5858 		;	/* do nothing */
5859 	else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5860 		dev_err(hub_dev, "get_hub_status failed\n");
5861 	else {
5862 		if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5863 			dev_dbg(hub_dev, "power change\n");
5864 			clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5865 			if (hubstatus & HUB_STATUS_LOCAL_POWER)
5866 				/* FIXME: Is this always true? */
5867 				hub->limited_power = 1;
5868 			else
5869 				hub->limited_power = 0;
5870 		}
5871 		if (hubchange & HUB_CHANGE_OVERCURRENT) {
5872 			u16 status = 0;
5873 			u16 unused;
5874 
5875 			dev_dbg(hub_dev, "over-current change\n");
5876 			clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5877 			msleep(500);	/* Cool down */
5878 			hub_power_on(hub, true);
5879 			hub_hub_status(hub, &status, &unused);
5880 			if (status & HUB_STATUS_OVERCURRENT)
5881 				dev_err(hub_dev, "over-current condition\n");
5882 		}
5883 	}
5884 
5885 out_autopm:
5886 	/* Balance the usb_autopm_get_interface() above */
5887 	usb_autopm_put_interface_no_suspend(intf);
5888 out_hdev_lock:
5889 	usb_unlock_device(hdev);
5890 
5891 	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
5892 	usb_autopm_put_interface(intf);
5893 	kref_put(&hub->kref, hub_release);
5894 
5895 	kcov_remote_stop();
5896 }
5897 
5898 static const struct usb_device_id hub_id_table[] = {
5899     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5900                    | USB_DEVICE_ID_MATCH_PRODUCT
5901                    | USB_DEVICE_ID_MATCH_INT_CLASS,
5902       .idVendor = USB_VENDOR_SMSC,
5903       .idProduct = USB_PRODUCT_USB5534B,
5904       .bInterfaceClass = USB_CLASS_HUB,
5905       .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5906     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5907                    | USB_DEVICE_ID_MATCH_PRODUCT,
5908       .idVendor = USB_VENDOR_CYPRESS,
5909       .idProduct = USB_PRODUCT_CY7C65632,
5910       .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5911     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5912 			| USB_DEVICE_ID_MATCH_INT_CLASS,
5913       .idVendor = USB_VENDOR_GENESYS_LOGIC,
5914       .bInterfaceClass = USB_CLASS_HUB,
5915       .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5916     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5917 			| USB_DEVICE_ID_MATCH_PRODUCT,
5918       .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5919       .idProduct = USB_PRODUCT_TUSB8041_USB2,
5920       .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5921     { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5922 			| USB_DEVICE_ID_MATCH_PRODUCT,
5923       .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5924       .idProduct = USB_PRODUCT_TUSB8041_USB3,
5925       .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5926 	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5927 			| USB_DEVICE_ID_MATCH_PRODUCT,
5928 	  .idVendor = USB_VENDOR_MICROCHIP,
5929 	  .idProduct = USB_PRODUCT_USB4913,
5930 	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
5931 	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5932 			| USB_DEVICE_ID_MATCH_PRODUCT,
5933 	  .idVendor = USB_VENDOR_MICROCHIP,
5934 	  .idProduct = USB_PRODUCT_USB4914,
5935 	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
5936 	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5937 			| USB_DEVICE_ID_MATCH_PRODUCT,
5938 	  .idVendor = USB_VENDOR_MICROCHIP,
5939 	  .idProduct = USB_PRODUCT_USB4915,
5940 	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
5941     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
5942       .bDeviceClass = USB_CLASS_HUB},
5943     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
5944       .bInterfaceClass = USB_CLASS_HUB},
5945     { }						/* Terminating entry */
5946 };
5947 
5948 MODULE_DEVICE_TABLE(usb, hub_id_table);
5949 
5950 static struct usb_driver hub_driver = {
5951 	.name =		"hub",
5952 	.probe =	hub_probe,
5953 	.disconnect =	hub_disconnect,
5954 	.suspend =	hub_suspend,
5955 	.resume =	hub_resume,
5956 	.reset_resume =	hub_reset_resume,
5957 	.pre_reset =	hub_pre_reset,
5958 	.post_reset =	hub_post_reset,
5959 	.unlocked_ioctl = hub_ioctl,
5960 	.id_table =	hub_id_table,
5961 	.supports_autosuspend =	1,
5962 };
5963 
usb_hub_init(void)5964 int usb_hub_init(void)
5965 {
5966 	if (usb_register(&hub_driver) < 0) {
5967 		printk(KERN_ERR "%s: can't register hub driver\n",
5968 			usbcore_name);
5969 		return -1;
5970 	}
5971 
5972 	/*
5973 	 * The workqueue needs to be freezable to avoid interfering with
5974 	 * USB-PERSIST port handover. Otherwise it might see that a full-speed
5975 	 * device was gone before the EHCI controller had handed its port
5976 	 * over to the companion full-speed controller.
5977 	 */
5978 	hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
5979 	if (hub_wq)
5980 		return 0;
5981 
5982 	/* Fall through if kernel_thread failed */
5983 	usb_deregister(&hub_driver);
5984 	pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
5985 
5986 	return -1;
5987 }
5988 
usb_hub_cleanup(void)5989 void usb_hub_cleanup(void)
5990 {
5991 	destroy_workqueue(hub_wq);
5992 
5993 	/*
5994 	 * Hub resources are freed for us by usb_deregister. It calls
5995 	 * usb_driver_purge on every device which in turn calls that
5996 	 * devices disconnect function if it is using this driver.
5997 	 * The hub_disconnect function takes care of releasing the
5998 	 * individual hub resources. -greg
5999 	 */
6000 	usb_deregister(&hub_driver);
6001 } /* usb_hub_cleanup() */
6002 
6003 /**
6004  * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
6005  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
6006  *
6007  * WARNING - don't use this routine to reset a composite device
6008  * (one with multiple interfaces owned by separate drivers)!
6009  * Use usb_reset_device() instead.
6010  *
6011  * Do a port reset, reassign the device's address, and establish its
6012  * former operating configuration.  If the reset fails, or the device's
6013  * descriptors change from their values before the reset, or the original
6014  * configuration and altsettings cannot be restored, a flag will be set
6015  * telling hub_wq to pretend the device has been disconnected and then
6016  * re-connected.  All drivers will be unbound, and the device will be
6017  * re-enumerated and probed all over again.
6018  *
6019  * Return: 0 if the reset succeeded, -ENODEV if the device has been
6020  * flagged for logical disconnection, or some other negative error code
6021  * if the reset wasn't even attempted.
6022  *
6023  * Note:
6024  * The caller must own the device lock and the port lock, the latter is
6025  * taken by usb_reset_device().  For example, it's safe to use
6026  * usb_reset_device() from a driver probe() routine after downloading
6027  * new firmware.  For calls that might not occur during probe(), drivers
6028  * should lock the device using usb_lock_device_for_reset().
6029  *
6030  * Locking exception: This routine may also be called from within an
6031  * autoresume handler.  Such usage won't conflict with other tasks
6032  * holding the device lock because these tasks should always call
6033  * usb_autopm_resume_device(), thereby preventing any unwanted
6034  * autoresume.  The autoresume handler is expected to have already
6035  * acquired the port lock before calling this routine.
6036  */
usb_reset_and_verify_device(struct usb_device * udev)6037 static int usb_reset_and_verify_device(struct usb_device *udev)
6038 {
6039 	struct usb_device		*parent_hdev = udev->parent;
6040 	struct usb_hub			*parent_hub;
6041 	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
6042 	struct usb_device_descriptor	descriptor;
6043 	struct usb_host_bos		*bos;
6044 	int				i, j, ret = 0;
6045 	int				port1 = udev->portnum;
6046 
6047 	if (udev->state == USB_STATE_NOTATTACHED ||
6048 			udev->state == USB_STATE_SUSPENDED) {
6049 		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
6050 				udev->state);
6051 		return -EINVAL;
6052 	}
6053 
6054 	if (!parent_hdev)
6055 		return -EISDIR;
6056 
6057 	parent_hub = usb_hub_to_struct_hub(parent_hdev);
6058 
6059 	/* Disable USB2 hardware LPM.
6060 	 * It will be re-enabled by the enumeration process.
6061 	 */
6062 	usb_disable_usb2_hardware_lpm(udev);
6063 
6064 	bos = udev->bos;
6065 	udev->bos = NULL;
6066 
6067 	mutex_lock(hcd->address0_mutex);
6068 
6069 	for (i = 0; i < PORT_INIT_TRIES; ++i) {
6070 		if (hub_port_stop_enumerate(parent_hub, port1, i)) {
6071 			ret = -ENODEV;
6072 			break;
6073 		}
6074 
6075 		/* ep0 maxpacket size may change; let the HCD know about it.
6076 		 * Other endpoints will be handled by re-enumeration. */
6077 		usb_ep0_reinit(udev);
6078 		ret = hub_port_init(parent_hub, udev, port1, i, &descriptor);
6079 		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
6080 			break;
6081 	}
6082 	mutex_unlock(hcd->address0_mutex);
6083 
6084 	if (ret < 0)
6085 		goto re_enumerate;
6086 
6087 	/* Device might have changed firmware (DFU or similar) */
6088 	if (descriptors_changed(udev, &descriptor, bos)) {
6089 		dev_info(&udev->dev, "device firmware changed\n");
6090 		goto re_enumerate;
6091 	}
6092 
6093 	/* Restore the device's previous configuration */
6094 	if (!udev->actconfig)
6095 		goto done;
6096 
6097 	mutex_lock(hcd->bandwidth_mutex);
6098 	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
6099 	if (ret < 0) {
6100 		dev_warn(&udev->dev,
6101 				"Busted HC?  Not enough HCD resources for "
6102 				"old configuration.\n");
6103 		mutex_unlock(hcd->bandwidth_mutex);
6104 		goto re_enumerate;
6105 	}
6106 	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
6107 			USB_REQ_SET_CONFIGURATION, 0,
6108 			udev->actconfig->desc.bConfigurationValue, 0,
6109 			NULL, 0, USB_CTRL_SET_TIMEOUT);
6110 	if (ret < 0) {
6111 		dev_err(&udev->dev,
6112 			"can't restore configuration #%d (error=%d)\n",
6113 			udev->actconfig->desc.bConfigurationValue, ret);
6114 		mutex_unlock(hcd->bandwidth_mutex);
6115 		goto re_enumerate;
6116 	}
6117 	mutex_unlock(hcd->bandwidth_mutex);
6118 	usb_set_device_state(udev, USB_STATE_CONFIGURED);
6119 
6120 	/* Put interfaces back into the same altsettings as before.
6121 	 * Don't bother to send the Set-Interface request for interfaces
6122 	 * that were already in altsetting 0; besides being unnecessary,
6123 	 * many devices can't handle it.  Instead just reset the host-side
6124 	 * endpoint state.
6125 	 */
6126 	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
6127 		struct usb_host_config *config = udev->actconfig;
6128 		struct usb_interface *intf = config->interface[i];
6129 		struct usb_interface_descriptor *desc;
6130 
6131 		desc = &intf->cur_altsetting->desc;
6132 		if (desc->bAlternateSetting == 0) {
6133 			usb_disable_interface(udev, intf, true);
6134 			usb_enable_interface(udev, intf, true);
6135 			ret = 0;
6136 		} else {
6137 			/* Let the bandwidth allocation function know that this
6138 			 * device has been reset, and it will have to use
6139 			 * alternate setting 0 as the current alternate setting.
6140 			 */
6141 			intf->resetting_device = 1;
6142 			ret = usb_set_interface(udev, desc->bInterfaceNumber,
6143 					desc->bAlternateSetting);
6144 			intf->resetting_device = 0;
6145 		}
6146 		if (ret < 0) {
6147 			dev_err(&udev->dev, "failed to restore interface %d "
6148 				"altsetting %d (error=%d)\n",
6149 				desc->bInterfaceNumber,
6150 				desc->bAlternateSetting,
6151 				ret);
6152 			goto re_enumerate;
6153 		}
6154 		/* Resetting also frees any allocated streams */
6155 		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
6156 			intf->cur_altsetting->endpoint[j].streams = 0;
6157 	}
6158 
6159 done:
6160 	/* Now that the alt settings are re-installed, enable LTM and LPM. */
6161 	usb_enable_usb2_hardware_lpm(udev);
6162 	usb_unlocked_enable_lpm(udev);
6163 	usb_enable_ltm(udev);
6164 	usb_release_bos_descriptor(udev);
6165 	udev->bos = bos;
6166 	return 0;
6167 
6168 re_enumerate:
6169 	usb_release_bos_descriptor(udev);
6170 	udev->bos = bos;
6171 	hub_port_logical_disconnect(parent_hub, port1);
6172 	return -ENODEV;
6173 }
6174 
6175 /**
6176  * usb_reset_device - warn interface drivers and perform a USB port reset
6177  * @udev: device to reset (not in NOTATTACHED state)
6178  *
6179  * Warns all drivers bound to registered interfaces (using their pre_reset
6180  * method), performs the port reset, and then lets the drivers know that
6181  * the reset is over (using their post_reset method).
6182  *
6183  * Return: The same as for usb_reset_and_verify_device().
6184  * However, if a reset is already in progress (for instance, if a
6185  * driver doesn't have pre_reset() or post_reset() callbacks, and while
6186  * being unbound or re-bound during the ongoing reset its disconnect()
6187  * or probe() routine tries to perform a second, nested reset), the
6188  * routine returns -EINPROGRESS.
6189  *
6190  * Note:
6191  * The caller must own the device lock.  For example, it's safe to use
6192  * this from a driver probe() routine after downloading new firmware.
6193  * For calls that might not occur during probe(), drivers should lock
6194  * the device using usb_lock_device_for_reset().
6195  *
6196  * If an interface is currently being probed or disconnected, we assume
6197  * its driver knows how to handle resets.  For all other interfaces,
6198  * if the driver doesn't have pre_reset and post_reset methods then
6199  * we attempt to unbind it and rebind afterward.
6200  */
usb_reset_device(struct usb_device * udev)6201 int usb_reset_device(struct usb_device *udev)
6202 {
6203 	int ret;
6204 	int i;
6205 	unsigned int noio_flag;
6206 	struct usb_port *port_dev;
6207 	struct usb_host_config *config = udev->actconfig;
6208 	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
6209 
6210 	if (udev->state == USB_STATE_NOTATTACHED) {
6211 		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
6212 				udev->state);
6213 		return -EINVAL;
6214 	}
6215 
6216 	if (!udev->parent) {
6217 		/* this requires hcd-specific logic; see ohci_restart() */
6218 		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
6219 		return -EISDIR;
6220 	}
6221 
6222 	if (udev->reset_in_progress)
6223 		return -EINPROGRESS;
6224 	udev->reset_in_progress = 1;
6225 
6226 	port_dev = hub->ports[udev->portnum - 1];
6227 
6228 	/*
6229 	 * Don't allocate memory with GFP_KERNEL in current
6230 	 * context to avoid possible deadlock if usb mass
6231 	 * storage interface or usbnet interface(iSCSI case)
6232 	 * is included in current configuration. The easist
6233 	 * approach is to do it for every device reset,
6234 	 * because the device 'memalloc_noio' flag may have
6235 	 * not been set before reseting the usb device.
6236 	 */
6237 	noio_flag = memalloc_noio_save();
6238 
6239 	/* Prevent autosuspend during the reset */
6240 	usb_autoresume_device(udev);
6241 
6242 	if (config) {
6243 		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
6244 			struct usb_interface *cintf = config->interface[i];
6245 			struct usb_driver *drv;
6246 			int unbind = 0;
6247 
6248 			if (cintf->dev.driver) {
6249 				drv = to_usb_driver(cintf->dev.driver);
6250 				if (drv->pre_reset && drv->post_reset)
6251 					unbind = (drv->pre_reset)(cintf);
6252 				else if (cintf->condition ==
6253 						USB_INTERFACE_BOUND)
6254 					unbind = 1;
6255 				if (unbind)
6256 					usb_forced_unbind_intf(cintf);
6257 			}
6258 		}
6259 	}
6260 
6261 	usb_lock_port(port_dev);
6262 	ret = usb_reset_and_verify_device(udev);
6263 	usb_unlock_port(port_dev);
6264 
6265 	if (config) {
6266 		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
6267 			struct usb_interface *cintf = config->interface[i];
6268 			struct usb_driver *drv;
6269 			int rebind = cintf->needs_binding;
6270 
6271 			if (!rebind && cintf->dev.driver) {
6272 				drv = to_usb_driver(cintf->dev.driver);
6273 				if (drv->post_reset)
6274 					rebind = (drv->post_reset)(cintf);
6275 				else if (cintf->condition ==
6276 						USB_INTERFACE_BOUND)
6277 					rebind = 1;
6278 				if (rebind)
6279 					cintf->needs_binding = 1;
6280 			}
6281 		}
6282 
6283 		/* If the reset failed, hub_wq will unbind drivers later */
6284 		if (ret == 0)
6285 			usb_unbind_and_rebind_marked_interfaces(udev);
6286 	}
6287 
6288 	usb_autosuspend_device(udev);
6289 	memalloc_noio_restore(noio_flag);
6290 	udev->reset_in_progress = 0;
6291 	return ret;
6292 }
6293 EXPORT_SYMBOL_GPL(usb_reset_device);
6294 
6295 
6296 /**
6297  * usb_queue_reset_device - Reset a USB device from an atomic context
6298  * @iface: USB interface belonging to the device to reset
6299  *
6300  * This function can be used to reset a USB device from an atomic
6301  * context, where usb_reset_device() won't work (as it blocks).
6302  *
6303  * Doing a reset via this method is functionally equivalent to calling
6304  * usb_reset_device(), except for the fact that it is delayed to a
6305  * workqueue. This means that any drivers bound to other interfaces
6306  * might be unbound, as well as users from usbfs in user space.
6307  *
6308  * Corner cases:
6309  *
6310  * - Scheduling two resets at the same time from two different drivers
6311  *   attached to two different interfaces of the same device is
6312  *   possible; depending on how the driver attached to each interface
6313  *   handles ->pre_reset(), the second reset might happen or not.
6314  *
6315  * - If the reset is delayed so long that the interface is unbound from
6316  *   its driver, the reset will be skipped.
6317  *
6318  * - This function can be called during .probe().  It can also be called
6319  *   during .disconnect(), but doing so is pointless because the reset
6320  *   will not occur.  If you really want to reset the device during
6321  *   .disconnect(), call usb_reset_device() directly -- but watch out
6322  *   for nested unbinding issues!
6323  */
usb_queue_reset_device(struct usb_interface * iface)6324 void usb_queue_reset_device(struct usb_interface *iface)
6325 {
6326 	if (schedule_work(&iface->reset_ws))
6327 		usb_get_intf(iface);
6328 }
6329 EXPORT_SYMBOL_GPL(usb_queue_reset_device);
6330 
6331 /**
6332  * usb_hub_find_child - Get the pointer of child device
6333  * attached to the port which is specified by @port1.
6334  * @hdev: USB device belonging to the usb hub
6335  * @port1: port num to indicate which port the child device
6336  *	is attached to.
6337  *
6338  * USB drivers call this function to get hub's child device
6339  * pointer.
6340  *
6341  * Return: %NULL if input param is invalid and
6342  * child's usb_device pointer if non-NULL.
6343  */
usb_hub_find_child(struct usb_device * hdev,int port1)6344 struct usb_device *usb_hub_find_child(struct usb_device *hdev,
6345 		int port1)
6346 {
6347 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6348 
6349 	if (port1 < 1 || port1 > hdev->maxchild)
6350 		return NULL;
6351 	return hub->ports[port1 - 1]->child;
6352 }
6353 EXPORT_SYMBOL_GPL(usb_hub_find_child);
6354 
usb_hub_adjust_deviceremovable(struct usb_device * hdev,struct usb_hub_descriptor * desc)6355 void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
6356 		struct usb_hub_descriptor *desc)
6357 {
6358 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6359 	enum usb_port_connect_type connect_type;
6360 	int i;
6361 
6362 	if (!hub)
6363 		return;
6364 
6365 	if (!hub_is_superspeed(hdev)) {
6366 		for (i = 1; i <= hdev->maxchild; i++) {
6367 			struct usb_port *port_dev = hub->ports[i - 1];
6368 
6369 			connect_type = port_dev->connect_type;
6370 			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6371 				u8 mask = 1 << (i%8);
6372 
6373 				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
6374 					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6375 					desc->u.hs.DeviceRemovable[i/8]	|= mask;
6376 				}
6377 			}
6378 		}
6379 	} else {
6380 		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
6381 
6382 		for (i = 1; i <= hdev->maxchild; i++) {
6383 			struct usb_port *port_dev = hub->ports[i - 1];
6384 
6385 			connect_type = port_dev->connect_type;
6386 			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6387 				u16 mask = 1 << i;
6388 
6389 				if (!(port_removable & mask)) {
6390 					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6391 					port_removable |= mask;
6392 				}
6393 			}
6394 		}
6395 
6396 		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
6397 	}
6398 }
6399 
6400 #ifdef CONFIG_ACPI
6401 /**
6402  * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
6403  * @hdev: USB device belonging to the usb hub
6404  * @port1: port num of the port
6405  *
6406  * Return: Port's acpi handle if successful, %NULL if params are
6407  * invalid.
6408  */
usb_get_hub_port_acpi_handle(struct usb_device * hdev,int port1)6409 acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
6410 	int port1)
6411 {
6412 	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6413 
6414 	if (!hub)
6415 		return NULL;
6416 
6417 	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
6418 }
6419 #endif
6420