1 /*
2  * cdc_ncm.c
3  *
4  * Copyright (C) ST-Ericsson 2010-2012
5  * Contact: Alexey Orishko <alexey.orishko@stericsson.com>
6  * Original author: Hans Petter Selasky <hans.petter.selasky@stericsson.com>
7  *
8  * USB Host Driver for Network Control Model (NCM)
9  * http://www.usb.org/developers/devclass_docs/NCM10.zip
10  *
11  * The NCM encoding, decoding and initialization logic
12  * derives from FreeBSD 8.x. if_cdce.c and if_cdcereg.h
13  *
14  * This software is available to you under a choice of one of two
15  * licenses. You may choose this file to be licensed under the terms
16  * of the GNU General Public License (GPL) Version 2 or the 2-clause
17  * BSD license listed below:
18  *
19  * Redistribution and use in source and binary forms, with or without
20  * modification, are permitted provided that the following conditions
21  * are met:
22  * 1. Redistributions of source code must retain the above copyright
23  *    notice, this list of conditions and the following disclaimer.
24  * 2. Redistributions in binary form must reproduce the above copyright
25  *    notice, this list of conditions and the following disclaimer in the
26  *    documentation and/or other materials provided with the distribution.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #include <linux/module.h>
42 #include <linux/init.h>
43 #include <linux/netdevice.h>
44 #include <linux/ctype.h>
45 #include <linux/ethtool.h>
46 #include <linux/workqueue.h>
47 #include <linux/mii.h>
48 #include <linux/crc32.h>
49 #include <linux/usb.h>
50 #include <linux/hrtimer.h>
51 #include <linux/atomic.h>
52 #include <linux/usb/usbnet.h>
53 #include <linux/usb/cdc.h>
54 
55 #define	DRIVER_VERSION				"14-Mar-2012"
56 
57 /* CDC NCM subclass 3.2.1 */
58 #define USB_CDC_NCM_NDP16_LENGTH_MIN		0x10
59 
60 /* Maximum NTB length */
61 #define	CDC_NCM_NTB_MAX_SIZE_TX			32768	/* bytes */
62 #define	CDC_NCM_NTB_MAX_SIZE_RX			32768	/* bytes */
63 
64 /* Minimum value for MaxDatagramSize, ch. 6.2.9 */
65 #define	CDC_NCM_MIN_DATAGRAM_SIZE		1514	/* bytes */
66 
67 #define	CDC_NCM_MIN_TX_PKT			512	/* bytes */
68 
69 /* Default value for MaxDatagramSize */
70 #define	CDC_NCM_MAX_DATAGRAM_SIZE		8192	/* bytes */
71 
72 /*
73  * Maximum amount of datagrams in NCM Datagram Pointer Table, not counting
74  * the last NULL entry.
75  */
76 #define	CDC_NCM_DPT_DATAGRAMS_MAX		40
77 
78 /* Restart the timer, if amount of datagrams is less than given value */
79 #define	CDC_NCM_RESTART_TIMER_DATAGRAM_CNT	3
80 #define	CDC_NCM_TIMER_PENDING_CNT		2
81 #define CDC_NCM_TIMER_INTERVAL			(400UL * NSEC_PER_USEC)
82 
83 /* The following macro defines the minimum header space */
84 #define	CDC_NCM_MIN_HDR_SIZE \
85 	(sizeof(struct usb_cdc_ncm_nth16) + sizeof(struct usb_cdc_ncm_ndp16) + \
86 	(CDC_NCM_DPT_DATAGRAMS_MAX + 1) * sizeof(struct usb_cdc_ncm_dpe16))
87 
88 struct cdc_ncm_data {
89 	struct usb_cdc_ncm_nth16 nth16;
90 	struct usb_cdc_ncm_ndp16 ndp16;
91 	struct usb_cdc_ncm_dpe16 dpe16[CDC_NCM_DPT_DATAGRAMS_MAX + 1];
92 };
93 
94 struct cdc_ncm_ctx {
95 	struct cdc_ncm_data tx_ncm;
96 	struct usb_cdc_ncm_ntb_parameters ncm_parm;
97 	struct hrtimer tx_timer;
98 	struct tasklet_struct bh;
99 
100 	const struct usb_cdc_ncm_desc *func_desc;
101 	const struct usb_cdc_header_desc *header_desc;
102 	const struct usb_cdc_union_desc *union_desc;
103 	const struct usb_cdc_ether_desc *ether_desc;
104 
105 	struct net_device *netdev;
106 	struct usb_device *udev;
107 	struct usb_host_endpoint *in_ep;
108 	struct usb_host_endpoint *out_ep;
109 	struct usb_host_endpoint *status_ep;
110 	struct usb_interface *intf;
111 	struct usb_interface *control;
112 	struct usb_interface *data;
113 
114 	struct sk_buff *tx_curr_skb;
115 	struct sk_buff *tx_rem_skb;
116 
117 	spinlock_t mtx;
118 	atomic_t stop;
119 
120 	u32 tx_timer_pending;
121 	u32 tx_curr_offset;
122 	u32 tx_curr_last_offset;
123 	u32 tx_curr_frame_num;
124 	u32 rx_speed;
125 	u32 tx_speed;
126 	u32 rx_max;
127 	u32 tx_max;
128 	u32 max_datagram_size;
129 	u16 tx_max_datagrams;
130 	u16 tx_remainder;
131 	u16 tx_modulus;
132 	u16 tx_ndp_modulus;
133 	u16 tx_seq;
134 	u16 rx_seq;
135 	u16 connected;
136 };
137 
138 static void cdc_ncm_txpath_bh(unsigned long param);
139 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
140 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
141 static const struct driver_info cdc_ncm_info;
142 static struct usb_driver cdc_ncm_driver;
143 static const struct ethtool_ops cdc_ncm_ethtool_ops;
144 
145 static const struct usb_device_id cdc_devs[] = {
146 	{ USB_INTERFACE_INFO(USB_CLASS_COMM,
147 		USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
148 		.driver_info = (unsigned long)&cdc_ncm_info,
149 	},
150 	{
151 	},
152 };
153 
154 MODULE_DEVICE_TABLE(usb, cdc_devs);
155 
156 static void
cdc_ncm_get_drvinfo(struct net_device * net,struct ethtool_drvinfo * info)157 cdc_ncm_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *info)
158 {
159 	struct usbnet *dev = netdev_priv(net);
160 
161 	strncpy(info->driver, dev->driver_name, sizeof(info->driver));
162 	strncpy(info->version, DRIVER_VERSION, sizeof(info->version));
163 	strncpy(info->fw_version, dev->driver_info->description,
164 		sizeof(info->fw_version));
165 	usb_make_path(dev->udev, info->bus_info, sizeof(info->bus_info));
166 }
167 
cdc_ncm_setup(struct cdc_ncm_ctx * ctx)168 static u8 cdc_ncm_setup(struct cdc_ncm_ctx *ctx)
169 {
170 	u32 val;
171 	u8 flags;
172 	u8 iface_no;
173 	int err;
174 	u16 ntb_fmt_supported;
175 
176 	iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;
177 
178 	err = usb_control_msg(ctx->udev,
179 				usb_rcvctrlpipe(ctx->udev, 0),
180 				USB_CDC_GET_NTB_PARAMETERS,
181 				USB_TYPE_CLASS | USB_DIR_IN
182 				 | USB_RECIP_INTERFACE,
183 				0, iface_no, &ctx->ncm_parm,
184 				sizeof(ctx->ncm_parm), 10000);
185 	if (err < 0) {
186 		pr_debug("failed GET_NTB_PARAMETERS\n");
187 		return 1;
188 	}
189 
190 	/* read correct set of parameters according to device mode */
191 	ctx->rx_max = le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize);
192 	ctx->tx_max = le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize);
193 	ctx->tx_remainder = le16_to_cpu(ctx->ncm_parm.wNdpOutPayloadRemainder);
194 	ctx->tx_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutDivisor);
195 	ctx->tx_ndp_modulus = le16_to_cpu(ctx->ncm_parm.wNdpOutAlignment);
196 	/* devices prior to NCM Errata shall set this field to zero */
197 	ctx->tx_max_datagrams = le16_to_cpu(ctx->ncm_parm.wNtbOutMaxDatagrams);
198 	ntb_fmt_supported = le16_to_cpu(ctx->ncm_parm.bmNtbFormatsSupported);
199 
200 	if (ctx->func_desc != NULL)
201 		flags = ctx->func_desc->bmNetworkCapabilities;
202 	else
203 		flags = 0;
204 
205 	pr_debug("dwNtbInMaxSize=%u dwNtbOutMaxSize=%u "
206 		 "wNdpOutPayloadRemainder=%u wNdpOutDivisor=%u "
207 		 "wNdpOutAlignment=%u wNtbOutMaxDatagrams=%u flags=0x%x\n",
208 		 ctx->rx_max, ctx->tx_max, ctx->tx_remainder, ctx->tx_modulus,
209 		 ctx->tx_ndp_modulus, ctx->tx_max_datagrams, flags);
210 
211 	/* max count of tx datagrams */
212 	if ((ctx->tx_max_datagrams == 0) ||
213 			(ctx->tx_max_datagrams > CDC_NCM_DPT_DATAGRAMS_MAX))
214 		ctx->tx_max_datagrams = CDC_NCM_DPT_DATAGRAMS_MAX;
215 
216 	/* verify maximum size of received NTB in bytes */
217 	if (ctx->rx_max < USB_CDC_NCM_NTB_MIN_IN_SIZE) {
218 		pr_debug("Using min receive length=%d\n",
219 						USB_CDC_NCM_NTB_MIN_IN_SIZE);
220 		ctx->rx_max = USB_CDC_NCM_NTB_MIN_IN_SIZE;
221 	}
222 
223 	if (ctx->rx_max > CDC_NCM_NTB_MAX_SIZE_RX) {
224 		pr_debug("Using default maximum receive length=%d\n",
225 						CDC_NCM_NTB_MAX_SIZE_RX);
226 		ctx->rx_max = CDC_NCM_NTB_MAX_SIZE_RX;
227 	}
228 
229 	/* inform device about NTB input size changes */
230 	if (ctx->rx_max != le32_to_cpu(ctx->ncm_parm.dwNtbInMaxSize)) {
231 
232 		if (flags & USB_CDC_NCM_NCAP_NTB_INPUT_SIZE) {
233 			struct usb_cdc_ncm_ndp_input_size *ndp_in_sz;
234 
235 			ndp_in_sz = kzalloc(sizeof(*ndp_in_sz), GFP_KERNEL);
236 			if (!ndp_in_sz) {
237 				err = -ENOMEM;
238 				goto size_err;
239 			}
240 
241 			err = usb_control_msg(ctx->udev,
242 					usb_sndctrlpipe(ctx->udev, 0),
243 					USB_CDC_SET_NTB_INPUT_SIZE,
244 					USB_TYPE_CLASS | USB_DIR_OUT
245 					 | USB_RECIP_INTERFACE,
246 					0, iface_no, ndp_in_sz, 8, 1000);
247 			kfree(ndp_in_sz);
248 		} else {
249 			__le32 *dwNtbInMaxSize;
250 			dwNtbInMaxSize = kzalloc(sizeof(*dwNtbInMaxSize),
251 					GFP_KERNEL);
252 			if (!dwNtbInMaxSize) {
253 				err = -ENOMEM;
254 				goto size_err;
255 			}
256 			*dwNtbInMaxSize = cpu_to_le32(ctx->rx_max);
257 
258 			err = usb_control_msg(ctx->udev,
259 					usb_sndctrlpipe(ctx->udev, 0),
260 					USB_CDC_SET_NTB_INPUT_SIZE,
261 					USB_TYPE_CLASS | USB_DIR_OUT
262 					 | USB_RECIP_INTERFACE,
263 					0, iface_no, dwNtbInMaxSize, 4, 1000);
264 			kfree(dwNtbInMaxSize);
265 		}
266 size_err:
267 		if (err < 0)
268 			pr_debug("Setting NTB Input Size failed\n");
269 	}
270 
271 	/* verify maximum size of transmitted NTB in bytes */
272 	if ((ctx->tx_max <
273 	    (CDC_NCM_MIN_HDR_SIZE + CDC_NCM_MIN_DATAGRAM_SIZE)) ||
274 	    (ctx->tx_max > CDC_NCM_NTB_MAX_SIZE_TX)) {
275 		pr_debug("Using default maximum transmit length=%d\n",
276 						CDC_NCM_NTB_MAX_SIZE_TX);
277 		ctx->tx_max = CDC_NCM_NTB_MAX_SIZE_TX;
278 	}
279 
280 	/*
281 	 * verify that the structure alignment is:
282 	 * - power of two
283 	 * - not greater than the maximum transmit length
284 	 * - not less than four bytes
285 	 */
286 	val = ctx->tx_ndp_modulus;
287 
288 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
289 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
290 		pr_debug("Using default alignment: 4 bytes\n");
291 		ctx->tx_ndp_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
292 	}
293 
294 	/*
295 	 * verify that the payload alignment is:
296 	 * - power of two
297 	 * - not greater than the maximum transmit length
298 	 * - not less than four bytes
299 	 */
300 	val = ctx->tx_modulus;
301 
302 	if ((val < USB_CDC_NCM_NDP_ALIGN_MIN_SIZE) ||
303 	    (val != ((-val) & val)) || (val >= ctx->tx_max)) {
304 		pr_debug("Using default transmit modulus: 4 bytes\n");
305 		ctx->tx_modulus = USB_CDC_NCM_NDP_ALIGN_MIN_SIZE;
306 	}
307 
308 	/* verify the payload remainder */
309 	if (ctx->tx_remainder >= ctx->tx_modulus) {
310 		pr_debug("Using default transmit remainder: 0 bytes\n");
311 		ctx->tx_remainder = 0;
312 	}
313 
314 	/* adjust TX-remainder according to NCM specification. */
315 	ctx->tx_remainder = ((ctx->tx_remainder - ETH_HLEN) &
316 						(ctx->tx_modulus - 1));
317 
318 	/* additional configuration */
319 
320 	/* set CRC Mode */
321 	if (flags & USB_CDC_NCM_NCAP_CRC_MODE) {
322 		err = usb_control_msg(ctx->udev, usb_sndctrlpipe(ctx->udev, 0),
323 				USB_CDC_SET_CRC_MODE,
324 				USB_TYPE_CLASS | USB_DIR_OUT
325 				 | USB_RECIP_INTERFACE,
326 				USB_CDC_NCM_CRC_NOT_APPENDED,
327 				iface_no, NULL, 0, 1000);
328 		if (err < 0)
329 			pr_debug("Setting CRC mode off failed\n");
330 	}
331 
332 	/* set NTB format, if both formats are supported */
333 	if (ntb_fmt_supported & USB_CDC_NCM_NTH32_SIGN) {
334 		err = usb_control_msg(ctx->udev, usb_sndctrlpipe(ctx->udev, 0),
335 				USB_CDC_SET_NTB_FORMAT, USB_TYPE_CLASS
336 				 | USB_DIR_OUT | USB_RECIP_INTERFACE,
337 				USB_CDC_NCM_NTB16_FORMAT,
338 				iface_no, NULL, 0, 1000);
339 		if (err < 0)
340 			pr_debug("Setting NTB format to 16-bit failed\n");
341 	}
342 
343 	ctx->max_datagram_size = CDC_NCM_MIN_DATAGRAM_SIZE;
344 
345 	/* set Max Datagram Size (MTU) */
346 	if (flags & USB_CDC_NCM_NCAP_MAX_DATAGRAM_SIZE) {
347 		__le16 *max_datagram_size;
348 		u16 eth_max_sz = le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
349 
350 		max_datagram_size = kzalloc(sizeof(*max_datagram_size),
351 				GFP_KERNEL);
352 		if (!max_datagram_size) {
353 			err = -ENOMEM;
354 			goto max_dgram_err;
355 		}
356 
357 		err = usb_control_msg(ctx->udev, usb_rcvctrlpipe(ctx->udev, 0),
358 				USB_CDC_GET_MAX_DATAGRAM_SIZE,
359 				USB_TYPE_CLASS | USB_DIR_IN
360 				 | USB_RECIP_INTERFACE,
361 				0, iface_no, max_datagram_size,
362 				2, 1000);
363 		if (err < 0) {
364 			pr_debug("GET_MAX_DATAGRAM_SIZE failed, use size=%u\n",
365 						CDC_NCM_MIN_DATAGRAM_SIZE);
366 		} else {
367 			ctx->max_datagram_size =
368 				le16_to_cpu(*max_datagram_size);
369 			/* Check Eth descriptor value */
370 			if (ctx->max_datagram_size > eth_max_sz)
371 					ctx->max_datagram_size = eth_max_sz;
372 
373 			if (ctx->max_datagram_size > CDC_NCM_MAX_DATAGRAM_SIZE)
374 				ctx->max_datagram_size =
375 						CDC_NCM_MAX_DATAGRAM_SIZE;
376 
377 			if (ctx->max_datagram_size < CDC_NCM_MIN_DATAGRAM_SIZE)
378 				ctx->max_datagram_size =
379 					CDC_NCM_MIN_DATAGRAM_SIZE;
380 
381 			/* if value changed, update device */
382 			if (ctx->max_datagram_size !=
383 					le16_to_cpu(*max_datagram_size)) {
384 				err = usb_control_msg(ctx->udev,
385 						usb_sndctrlpipe(ctx->udev, 0),
386 						USB_CDC_SET_MAX_DATAGRAM_SIZE,
387 						USB_TYPE_CLASS | USB_DIR_OUT
388 						 | USB_RECIP_INTERFACE,
389 						0,
390 						iface_no, max_datagram_size,
391 						2, 1000);
392 				if (err < 0)
393 					pr_debug("SET_MAX_DGRAM_SIZE failed\n");
394 			}
395 		}
396 		kfree(max_datagram_size);
397 	}
398 
399 max_dgram_err:
400 	if (ctx->netdev->mtu != (ctx->max_datagram_size - ETH_HLEN))
401 		ctx->netdev->mtu = ctx->max_datagram_size - ETH_HLEN;
402 
403 	return 0;
404 }
405 
406 static void
cdc_ncm_find_endpoints(struct cdc_ncm_ctx * ctx,struct usb_interface * intf)407 cdc_ncm_find_endpoints(struct cdc_ncm_ctx *ctx, struct usb_interface *intf)
408 {
409 	struct usb_host_endpoint *e;
410 	u8 ep;
411 
412 	for (ep = 0; ep < intf->cur_altsetting->desc.bNumEndpoints; ep++) {
413 
414 		e = intf->cur_altsetting->endpoint + ep;
415 		switch (e->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
416 		case USB_ENDPOINT_XFER_INT:
417 			if (usb_endpoint_dir_in(&e->desc)) {
418 				if (ctx->status_ep == NULL)
419 					ctx->status_ep = e;
420 			}
421 			break;
422 
423 		case USB_ENDPOINT_XFER_BULK:
424 			if (usb_endpoint_dir_in(&e->desc)) {
425 				if (ctx->in_ep == NULL)
426 					ctx->in_ep = e;
427 			} else {
428 				if (ctx->out_ep == NULL)
429 					ctx->out_ep = e;
430 			}
431 			break;
432 
433 		default:
434 			break;
435 		}
436 	}
437 }
438 
cdc_ncm_free(struct cdc_ncm_ctx * ctx)439 static void cdc_ncm_free(struct cdc_ncm_ctx *ctx)
440 {
441 	if (ctx == NULL)
442 		return;
443 
444 	if (ctx->tx_rem_skb != NULL) {
445 		dev_kfree_skb_any(ctx->tx_rem_skb);
446 		ctx->tx_rem_skb = NULL;
447 	}
448 
449 	if (ctx->tx_curr_skb != NULL) {
450 		dev_kfree_skb_any(ctx->tx_curr_skb);
451 		ctx->tx_curr_skb = NULL;
452 	}
453 
454 	kfree(ctx);
455 }
456 
cdc_ncm_bind(struct usbnet * dev,struct usb_interface * intf)457 static int cdc_ncm_bind(struct usbnet *dev, struct usb_interface *intf)
458 {
459 	struct cdc_ncm_ctx *ctx;
460 	struct usb_driver *driver;
461 	u8 *buf;
462 	int len;
463 	int temp;
464 	u8 iface_no;
465 
466 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
467 	if (ctx == NULL)
468 		return -ENODEV;
469 
470 	hrtimer_init(&ctx->tx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
471 	ctx->tx_timer.function = &cdc_ncm_tx_timer_cb;
472 	ctx->bh.data = (unsigned long)ctx;
473 	ctx->bh.func = cdc_ncm_txpath_bh;
474 	atomic_set(&ctx->stop, 0);
475 	spin_lock_init(&ctx->mtx);
476 	ctx->netdev = dev->net;
477 
478 	/* store ctx pointer in device data field */
479 	dev->data[0] = (unsigned long)ctx;
480 
481 	/* get some pointers */
482 	driver = driver_of(intf);
483 	buf = intf->cur_altsetting->extra;
484 	len = intf->cur_altsetting->extralen;
485 
486 	ctx->udev = dev->udev;
487 	ctx->intf = intf;
488 
489 	/* parse through descriptors associated with control interface */
490 	while ((len > 0) && (buf[0] > 2) && (buf[0] <= len)) {
491 
492 		if (buf[1] != USB_DT_CS_INTERFACE)
493 			goto advance;
494 
495 		switch (buf[2]) {
496 		case USB_CDC_UNION_TYPE:
497 			if (buf[0] < sizeof(*(ctx->union_desc)))
498 				break;
499 
500 			ctx->union_desc =
501 					(const struct usb_cdc_union_desc *)buf;
502 
503 			ctx->control = usb_ifnum_to_if(dev->udev,
504 					ctx->union_desc->bMasterInterface0);
505 			ctx->data = usb_ifnum_to_if(dev->udev,
506 					ctx->union_desc->bSlaveInterface0);
507 			break;
508 
509 		case USB_CDC_ETHERNET_TYPE:
510 			if (buf[0] < sizeof(*(ctx->ether_desc)))
511 				break;
512 
513 			ctx->ether_desc =
514 					(const struct usb_cdc_ether_desc *)buf;
515 			dev->hard_mtu =
516 				le16_to_cpu(ctx->ether_desc->wMaxSegmentSize);
517 
518 			if (dev->hard_mtu < CDC_NCM_MIN_DATAGRAM_SIZE)
519 				dev->hard_mtu =	CDC_NCM_MIN_DATAGRAM_SIZE;
520 			else if (dev->hard_mtu > CDC_NCM_MAX_DATAGRAM_SIZE)
521 				dev->hard_mtu =	CDC_NCM_MAX_DATAGRAM_SIZE;
522 			break;
523 
524 		case USB_CDC_NCM_TYPE:
525 			if (buf[0] < sizeof(*(ctx->func_desc)))
526 				break;
527 
528 			ctx->func_desc = (const struct usb_cdc_ncm_desc *)buf;
529 			break;
530 
531 		default:
532 			break;
533 		}
534 advance:
535 		/* advance to next descriptor */
536 		temp = buf[0];
537 		buf += temp;
538 		len -= temp;
539 	}
540 
541 	/* check if we got everything */
542 	if ((ctx->control == NULL) || (ctx->data == NULL) ||
543 	    (ctx->ether_desc == NULL) || (ctx->control != intf))
544 		goto error;
545 
546 	/* claim interfaces, if any */
547 	temp = usb_driver_claim_interface(driver, ctx->data, dev);
548 	if (temp)
549 		goto error;
550 
551 	iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber;
552 
553 	/* reset data interface */
554 	temp = usb_set_interface(dev->udev, iface_no, 0);
555 	if (temp)
556 		goto error2;
557 
558 	/* initialize data interface */
559 	if (cdc_ncm_setup(ctx))
560 		goto error2;
561 
562 	/* configure data interface */
563 	temp = usb_set_interface(dev->udev, iface_no, 1);
564 	if (temp)
565 		goto error2;
566 
567 	cdc_ncm_find_endpoints(ctx, ctx->data);
568 	cdc_ncm_find_endpoints(ctx, ctx->control);
569 
570 	if ((ctx->in_ep == NULL) || (ctx->out_ep == NULL) ||
571 	    (ctx->status_ep == NULL))
572 		goto error2;
573 
574 	dev->net->ethtool_ops = &cdc_ncm_ethtool_ops;
575 
576 	usb_set_intfdata(ctx->data, dev);
577 	usb_set_intfdata(ctx->control, dev);
578 	usb_set_intfdata(ctx->intf, dev);
579 
580 	temp = usbnet_get_ethernet_addr(dev, ctx->ether_desc->iMACAddress);
581 	if (temp)
582 		goto error2;
583 
584 	dev_info(&dev->udev->dev, "MAC-Address: %pM\n", dev->net->dev_addr);
585 
586 	dev->in = usb_rcvbulkpipe(dev->udev,
587 		ctx->in_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
588 	dev->out = usb_sndbulkpipe(dev->udev,
589 		ctx->out_ep->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
590 	dev->status = ctx->status_ep;
591 	dev->rx_urb_size = ctx->rx_max;
592 
593 	/*
594 	 * We should get an event when network connection is "connected" or
595 	 * "disconnected". Set network connection in "disconnected" state
596 	 * (carrier is OFF) during attach, so the IP network stack does not
597 	 * start IPv6 negotiation and more.
598 	 */
599 	netif_carrier_off(dev->net);
600 	ctx->tx_speed = ctx->rx_speed = 0;
601 	return 0;
602 
603 error2:
604 	usb_set_intfdata(ctx->control, NULL);
605 	usb_set_intfdata(ctx->data, NULL);
606 	usb_driver_release_interface(driver, ctx->data);
607 error:
608 	cdc_ncm_free((struct cdc_ncm_ctx *)dev->data[0]);
609 	dev->data[0] = 0;
610 	dev_info(&dev->udev->dev, "bind() failure\n");
611 	return -ENODEV;
612 }
613 
cdc_ncm_unbind(struct usbnet * dev,struct usb_interface * intf)614 static void cdc_ncm_unbind(struct usbnet *dev, struct usb_interface *intf)
615 {
616 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
617 	struct usb_driver *driver = driver_of(intf);
618 
619 	if (ctx == NULL)
620 		return;		/* no setup */
621 
622 	atomic_set(&ctx->stop, 1);
623 
624 	if (hrtimer_active(&ctx->tx_timer))
625 		hrtimer_cancel(&ctx->tx_timer);
626 
627 	tasklet_kill(&ctx->bh);
628 
629 	/* disconnect master --> disconnect slave */
630 	if (intf == ctx->control && ctx->data) {
631 		usb_set_intfdata(ctx->data, NULL);
632 		usb_driver_release_interface(driver, ctx->data);
633 		ctx->data = NULL;
634 
635 	} else if (intf == ctx->data && ctx->control) {
636 		usb_set_intfdata(ctx->control, NULL);
637 		usb_driver_release_interface(driver, ctx->control);
638 		ctx->control = NULL;
639 	}
640 
641 	usb_set_intfdata(ctx->intf, NULL);
642 	cdc_ncm_free(ctx);
643 }
644 
cdc_ncm_zero_fill(u8 * ptr,u32 first,u32 end,u32 max)645 static void cdc_ncm_zero_fill(u8 *ptr, u32 first, u32 end, u32 max)
646 {
647 	if (first >= max)
648 		return;
649 	if (first >= end)
650 		return;
651 	if (end > max)
652 		end = max;
653 	memset(ptr + first, 0, end - first);
654 }
655 
656 static struct sk_buff *
cdc_ncm_fill_tx_frame(struct cdc_ncm_ctx * ctx,struct sk_buff * skb)657 cdc_ncm_fill_tx_frame(struct cdc_ncm_ctx *ctx, struct sk_buff *skb)
658 {
659 	struct sk_buff *skb_out;
660 	u32 rem;
661 	u32 offset;
662 	u32 last_offset;
663 	u16 n = 0, index;
664 	u8 ready2send = 0;
665 
666 	/* if there is a remaining skb, it gets priority */
667 	if (skb != NULL)
668 		swap(skb, ctx->tx_rem_skb);
669 	else
670 		ready2send = 1;
671 
672 	/*
673 	 * +----------------+
674 	 * | skb_out        |
675 	 * +----------------+
676 	 *           ^ offset
677 	 *        ^ last_offset
678 	 */
679 
680 	/* check if we are resuming an OUT skb */
681 	if (ctx->tx_curr_skb != NULL) {
682 		/* pop variables */
683 		skb_out = ctx->tx_curr_skb;
684 		offset = ctx->tx_curr_offset;
685 		last_offset = ctx->tx_curr_last_offset;
686 		n = ctx->tx_curr_frame_num;
687 
688 	} else {
689 		/* reset variables */
690 		skb_out = alloc_skb((ctx->tx_max + 1), GFP_ATOMIC);
691 		if (skb_out == NULL) {
692 			if (skb != NULL) {
693 				dev_kfree_skb_any(skb);
694 				ctx->netdev->stats.tx_dropped++;
695 			}
696 			goto exit_no_skb;
697 		}
698 
699 		/* make room for NTH and NDP */
700 		offset = ALIGN(sizeof(struct usb_cdc_ncm_nth16),
701 					ctx->tx_ndp_modulus) +
702 					sizeof(struct usb_cdc_ncm_ndp16) +
703 					(ctx->tx_max_datagrams + 1) *
704 					sizeof(struct usb_cdc_ncm_dpe16);
705 
706 		/* store last valid offset before alignment */
707 		last_offset = offset;
708 		/* align first Datagram offset correctly */
709 		offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
710 		/* zero buffer till the first IP datagram */
711 		cdc_ncm_zero_fill(skb_out->data, 0, offset, offset);
712 		n = 0;
713 		ctx->tx_curr_frame_num = 0;
714 	}
715 
716 	for (; n < ctx->tx_max_datagrams; n++) {
717 		/* check if end of transmit buffer is reached */
718 		if (offset >= ctx->tx_max) {
719 			ready2send = 1;
720 			break;
721 		}
722 		/* compute maximum buffer size */
723 		rem = ctx->tx_max - offset;
724 
725 		if (skb == NULL) {
726 			skb = ctx->tx_rem_skb;
727 			ctx->tx_rem_skb = NULL;
728 
729 			/* check for end of skb */
730 			if (skb == NULL)
731 				break;
732 		}
733 
734 		if (skb->len > rem) {
735 			if (n == 0) {
736 				/* won't fit, MTU problem? */
737 				dev_kfree_skb_any(skb);
738 				skb = NULL;
739 				ctx->netdev->stats.tx_dropped++;
740 			} else {
741 				/* no room for skb - store for later */
742 				if (ctx->tx_rem_skb != NULL) {
743 					dev_kfree_skb_any(ctx->tx_rem_skb);
744 					ctx->netdev->stats.tx_dropped++;
745 				}
746 				ctx->tx_rem_skb = skb;
747 				skb = NULL;
748 				ready2send = 1;
749 			}
750 			break;
751 		}
752 
753 		memcpy(((u8 *)skb_out->data) + offset, skb->data, skb->len);
754 
755 		ctx->tx_ncm.dpe16[n].wDatagramLength = cpu_to_le16(skb->len);
756 		ctx->tx_ncm.dpe16[n].wDatagramIndex = cpu_to_le16(offset);
757 
758 		/* update offset */
759 		offset += skb->len;
760 
761 		/* store last valid offset before alignment */
762 		last_offset = offset;
763 
764 		/* align offset correctly */
765 		offset = ALIGN(offset, ctx->tx_modulus) + ctx->tx_remainder;
766 
767 		/* zero padding */
768 		cdc_ncm_zero_fill(skb_out->data, last_offset, offset,
769 								ctx->tx_max);
770 		dev_kfree_skb_any(skb);
771 		skb = NULL;
772 	}
773 
774 	/* free up any dangling skb */
775 	if (skb != NULL) {
776 		dev_kfree_skb_any(skb);
777 		skb = NULL;
778 		ctx->netdev->stats.tx_dropped++;
779 	}
780 
781 	ctx->tx_curr_frame_num = n;
782 
783 	if (n == 0) {
784 		/* wait for more frames */
785 		/* push variables */
786 		ctx->tx_curr_skb = skb_out;
787 		ctx->tx_curr_offset = offset;
788 		ctx->tx_curr_last_offset = last_offset;
789 		goto exit_no_skb;
790 
791 	} else if ((n < ctx->tx_max_datagrams) && (ready2send == 0)) {
792 		/* wait for more frames */
793 		/* push variables */
794 		ctx->tx_curr_skb = skb_out;
795 		ctx->tx_curr_offset = offset;
796 		ctx->tx_curr_last_offset = last_offset;
797 		/* set the pending count */
798 		if (n < CDC_NCM_RESTART_TIMER_DATAGRAM_CNT)
799 			ctx->tx_timer_pending = CDC_NCM_TIMER_PENDING_CNT;
800 		goto exit_no_skb;
801 
802 	} else {
803 		/* frame goes out */
804 		/* variables will be reset at next call */
805 	}
806 
807 	/* check for overflow */
808 	if (last_offset > ctx->tx_max)
809 		last_offset = ctx->tx_max;
810 
811 	/* revert offset */
812 	offset = last_offset;
813 
814 	/*
815 	 * If collected data size is less or equal CDC_NCM_MIN_TX_PKT bytes,
816 	 * we send buffers as it is. If we get more data, it would be more
817 	 * efficient for USB HS mobile device with DMA engine to receive a full
818 	 * size NTB, than canceling DMA transfer and receiving a short packet.
819 	 */
820 	if (offset > CDC_NCM_MIN_TX_PKT)
821 		offset = ctx->tx_max;
822 
823 	/* final zero padding */
824 	cdc_ncm_zero_fill(skb_out->data, last_offset, offset, ctx->tx_max);
825 
826 	/* store last offset */
827 	last_offset = offset;
828 
829 	if (((last_offset < ctx->tx_max) && ((last_offset %
830 			le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) ||
831 	    (((last_offset == ctx->tx_max) && ((ctx->tx_max %
832 		le16_to_cpu(ctx->out_ep->desc.wMaxPacketSize)) == 0)) &&
833 		(ctx->tx_max < le32_to_cpu(ctx->ncm_parm.dwNtbOutMaxSize)))) {
834 		/* force short packet */
835 		*(((u8 *)skb_out->data) + last_offset) = 0;
836 		last_offset++;
837 	}
838 
839 	/* zero the rest of the DPEs plus the last NULL entry */
840 	for (; n <= CDC_NCM_DPT_DATAGRAMS_MAX; n++) {
841 		ctx->tx_ncm.dpe16[n].wDatagramLength = 0;
842 		ctx->tx_ncm.dpe16[n].wDatagramIndex = 0;
843 	}
844 
845 	/* fill out 16-bit NTB header */
846 	ctx->tx_ncm.nth16.dwSignature = cpu_to_le32(USB_CDC_NCM_NTH16_SIGN);
847 	ctx->tx_ncm.nth16.wHeaderLength =
848 					cpu_to_le16(sizeof(ctx->tx_ncm.nth16));
849 	ctx->tx_ncm.nth16.wSequence = cpu_to_le16(ctx->tx_seq);
850 	ctx->tx_ncm.nth16.wBlockLength = cpu_to_le16(last_offset);
851 	index = ALIGN(sizeof(struct usb_cdc_ncm_nth16), ctx->tx_ndp_modulus);
852 	ctx->tx_ncm.nth16.wNdpIndex = cpu_to_le16(index);
853 
854 	memcpy(skb_out->data, &(ctx->tx_ncm.nth16), sizeof(ctx->tx_ncm.nth16));
855 	ctx->tx_seq++;
856 
857 	/* fill out 16-bit NDP table */
858 	ctx->tx_ncm.ndp16.dwSignature =
859 				cpu_to_le32(USB_CDC_NCM_NDP16_NOCRC_SIGN);
860 	rem = sizeof(ctx->tx_ncm.ndp16) + ((ctx->tx_curr_frame_num + 1) *
861 					sizeof(struct usb_cdc_ncm_dpe16));
862 	ctx->tx_ncm.ndp16.wLength = cpu_to_le16(rem);
863 	ctx->tx_ncm.ndp16.wNextNdpIndex = 0; /* reserved */
864 
865 	memcpy(((u8 *)skb_out->data) + index,
866 						&(ctx->tx_ncm.ndp16),
867 						sizeof(ctx->tx_ncm.ndp16));
868 
869 	memcpy(((u8 *)skb_out->data) + index + sizeof(ctx->tx_ncm.ndp16),
870 					&(ctx->tx_ncm.dpe16),
871 					(ctx->tx_curr_frame_num + 1) *
872 					sizeof(struct usb_cdc_ncm_dpe16));
873 
874 	/* set frame length */
875 	skb_put(skb_out, last_offset);
876 
877 	/* return skb */
878 	ctx->tx_curr_skb = NULL;
879 	ctx->netdev->stats.tx_packets += ctx->tx_curr_frame_num;
880 	return skb_out;
881 
882 exit_no_skb:
883 	/* Start timer, if there is a remaining skb */
884 	if (ctx->tx_curr_skb != NULL)
885 		cdc_ncm_tx_timeout_start(ctx);
886 	return NULL;
887 }
888 
cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx * ctx)889 static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx)
890 {
891 	/* start timer, if not already started */
892 	if (!(hrtimer_active(&ctx->tx_timer) || atomic_read(&ctx->stop)))
893 		hrtimer_start(&ctx->tx_timer,
894 				ktime_set(0, CDC_NCM_TIMER_INTERVAL),
895 				HRTIMER_MODE_REL);
896 }
897 
cdc_ncm_tx_timer_cb(struct hrtimer * timer)898 static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *timer)
899 {
900 	struct cdc_ncm_ctx *ctx =
901 			container_of(timer, struct cdc_ncm_ctx, tx_timer);
902 
903 	if (!atomic_read(&ctx->stop))
904 		tasklet_schedule(&ctx->bh);
905 	return HRTIMER_NORESTART;
906 }
907 
cdc_ncm_txpath_bh(unsigned long param)908 static void cdc_ncm_txpath_bh(unsigned long param)
909 {
910 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)param;
911 
912 	spin_lock_bh(&ctx->mtx);
913 	if (ctx->tx_timer_pending != 0) {
914 		ctx->tx_timer_pending--;
915 		cdc_ncm_tx_timeout_start(ctx);
916 		spin_unlock_bh(&ctx->mtx);
917 	} else if (ctx->netdev != NULL) {
918 		spin_unlock_bh(&ctx->mtx);
919 		netif_tx_lock_bh(ctx->netdev);
920 		usbnet_start_xmit(NULL, ctx->netdev);
921 		netif_tx_unlock_bh(ctx->netdev);
922 	}
923 }
924 
925 static struct sk_buff *
cdc_ncm_tx_fixup(struct usbnet * dev,struct sk_buff * skb,gfp_t flags)926 cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
927 {
928 	struct sk_buff *skb_out;
929 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
930 
931 	/*
932 	 * The Ethernet API we are using does not support transmitting
933 	 * multiple Ethernet frames in a single call. This driver will
934 	 * accumulate multiple Ethernet frames and send out a larger
935 	 * USB frame when the USB buffer is full or when a single jiffies
936 	 * timeout happens.
937 	 */
938 	if (ctx == NULL)
939 		goto error;
940 
941 	spin_lock_bh(&ctx->mtx);
942 	skb_out = cdc_ncm_fill_tx_frame(ctx, skb);
943 	spin_unlock_bh(&ctx->mtx);
944 	return skb_out;
945 
946 error:
947 	if (skb != NULL)
948 		dev_kfree_skb_any(skb);
949 
950 	return NULL;
951 }
952 
cdc_ncm_rx_fixup(struct usbnet * dev,struct sk_buff * skb_in)953 static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
954 {
955 	struct sk_buff *skb;
956 	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
957 	int len;
958 	int nframes;
959 	int x;
960 	int offset;
961 	struct usb_cdc_ncm_nth16 *nth16;
962 	struct usb_cdc_ncm_ndp16 *ndp16;
963 	struct usb_cdc_ncm_dpe16 *dpe16;
964 
965 	if (ctx == NULL)
966 		goto error;
967 
968 	if (skb_in->len < (sizeof(struct usb_cdc_ncm_nth16) +
969 					sizeof(struct usb_cdc_ncm_ndp16))) {
970 		pr_debug("frame too short\n");
971 		goto error;
972 	}
973 
974 	nth16 = (struct usb_cdc_ncm_nth16 *)skb_in->data;
975 
976 	if (le32_to_cpu(nth16->dwSignature) != USB_CDC_NCM_NTH16_SIGN) {
977 		pr_debug("invalid NTH16 signature <%u>\n",
978 					le32_to_cpu(nth16->dwSignature));
979 		goto error;
980 	}
981 
982 	len = le16_to_cpu(nth16->wBlockLength);
983 	if (len > ctx->rx_max) {
984 		pr_debug("unsupported NTB block length %u/%u\n", len,
985 								ctx->rx_max);
986 		goto error;
987 	}
988 
989 	if ((ctx->rx_seq + 1) != le16_to_cpu(nth16->wSequence) &&
990 		(ctx->rx_seq || le16_to_cpu(nth16->wSequence)) &&
991 		!((ctx->rx_seq == 0xffff) && !le16_to_cpu(nth16->wSequence))) {
992 		pr_debug("sequence number glitch prev=%d curr=%d\n",
993 				ctx->rx_seq, le16_to_cpu(nth16->wSequence));
994 	}
995 	ctx->rx_seq = le16_to_cpu(nth16->wSequence);
996 
997 	len = le16_to_cpu(nth16->wNdpIndex);
998 	if ((len + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) {
999 		pr_debug("invalid DPT16 index <%u>\n",
1000 					le16_to_cpu(nth16->wNdpIndex));
1001 		goto error;
1002 	}
1003 
1004 	ndp16 = (struct usb_cdc_ncm_ndp16 *)(((u8 *)skb_in->data) + len);
1005 
1006 	if (le32_to_cpu(ndp16->dwSignature) != USB_CDC_NCM_NDP16_NOCRC_SIGN) {
1007 		pr_debug("invalid DPT16 signature <%u>\n",
1008 					le32_to_cpu(ndp16->dwSignature));
1009 		goto error;
1010 	}
1011 
1012 	if (le16_to_cpu(ndp16->wLength) < USB_CDC_NCM_NDP16_LENGTH_MIN) {
1013 		pr_debug("invalid DPT16 length <%u>\n",
1014 					le32_to_cpu(ndp16->dwSignature));
1015 		goto error;
1016 	}
1017 
1018 	nframes = ((le16_to_cpu(ndp16->wLength) -
1019 					sizeof(struct usb_cdc_ncm_ndp16)) /
1020 					sizeof(struct usb_cdc_ncm_dpe16));
1021 	nframes--; /* we process NDP entries except for the last one */
1022 
1023 	len += sizeof(struct usb_cdc_ncm_ndp16);
1024 
1025 	if ((len + nframes * (sizeof(struct usb_cdc_ncm_dpe16))) >
1026 								skb_in->len) {
1027 		pr_debug("Invalid nframes = %d\n", nframes);
1028 		goto error;
1029 	}
1030 
1031 	dpe16 = (struct usb_cdc_ncm_dpe16 *)(((u8 *)skb_in->data) + len);
1032 
1033 	for (x = 0; x < nframes; x++, dpe16++) {
1034 		offset = le16_to_cpu(dpe16->wDatagramIndex);
1035 		len = le16_to_cpu(dpe16->wDatagramLength);
1036 
1037 		/*
1038 		 * CDC NCM ch. 3.7
1039 		 * All entries after first NULL entry are to be ignored
1040 		 */
1041 		if ((offset == 0) || (len == 0)) {
1042 			if (!x)
1043 				goto error; /* empty NTB */
1044 			break;
1045 		}
1046 
1047 		/* sanity checking */
1048 		if (((offset + len) > skb_in->len) ||
1049 				(len > ctx->rx_max) || (len < ETH_HLEN)) {
1050 			pr_debug("invalid frame detected (ignored)"
1051 					"offset[%u]=%u, length=%u, skb=%p\n",
1052 					x, offset, len, skb_in);
1053 			if (!x)
1054 				goto error;
1055 			break;
1056 
1057 		} else {
1058 			skb = skb_clone(skb_in, GFP_ATOMIC);
1059 			if (!skb)
1060 				goto error;
1061 			skb->len = len;
1062 			skb->data = ((u8 *)skb_in->data) + offset;
1063 			skb_set_tail_pointer(skb, len);
1064 			usbnet_skb_return(dev, skb);
1065 		}
1066 	}
1067 	return 1;
1068 error:
1069 	return 0;
1070 }
1071 
1072 static void
cdc_ncm_speed_change(struct cdc_ncm_ctx * ctx,struct usb_cdc_speed_change * data)1073 cdc_ncm_speed_change(struct cdc_ncm_ctx *ctx,
1074 		     struct usb_cdc_speed_change *data)
1075 {
1076 	uint32_t rx_speed = le32_to_cpu(data->DLBitRRate);
1077 	uint32_t tx_speed = le32_to_cpu(data->ULBitRate);
1078 
1079 	/*
1080 	 * Currently the USB-NET API does not support reporting the actual
1081 	 * device speed. Do print it instead.
1082 	 */
1083 	if ((tx_speed != ctx->tx_speed) || (rx_speed != ctx->rx_speed)) {
1084 		ctx->tx_speed = tx_speed;
1085 		ctx->rx_speed = rx_speed;
1086 
1087 		if ((tx_speed > 1000000) && (rx_speed > 1000000)) {
1088 			printk(KERN_INFO KBUILD_MODNAME
1089 				": %s: %u mbit/s downlink "
1090 				"%u mbit/s uplink\n",
1091 				ctx->netdev->name,
1092 				(unsigned int)(rx_speed / 1000000U),
1093 				(unsigned int)(tx_speed / 1000000U));
1094 		} else {
1095 			printk(KERN_INFO KBUILD_MODNAME
1096 				": %s: %u kbit/s downlink "
1097 				"%u kbit/s uplink\n",
1098 				ctx->netdev->name,
1099 				(unsigned int)(rx_speed / 1000U),
1100 				(unsigned int)(tx_speed / 1000U));
1101 		}
1102 	}
1103 }
1104 
cdc_ncm_status(struct usbnet * dev,struct urb * urb)1105 static void cdc_ncm_status(struct usbnet *dev, struct urb *urb)
1106 {
1107 	struct cdc_ncm_ctx *ctx;
1108 	struct usb_cdc_notification *event;
1109 
1110 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1111 
1112 	if (urb->actual_length < sizeof(*event))
1113 		return;
1114 
1115 	/* test for split data in 8-byte chunks */
1116 	if (test_and_clear_bit(EVENT_STS_SPLIT, &dev->flags)) {
1117 		cdc_ncm_speed_change(ctx,
1118 		      (struct usb_cdc_speed_change *)urb->transfer_buffer);
1119 		return;
1120 	}
1121 
1122 	event = urb->transfer_buffer;
1123 
1124 	switch (event->bNotificationType) {
1125 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
1126 		/*
1127 		 * According to the CDC NCM specification ch.7.1
1128 		 * USB_CDC_NOTIFY_NETWORK_CONNECTION notification shall be
1129 		 * sent by device after USB_CDC_NOTIFY_SPEED_CHANGE.
1130 		 */
1131 		ctx->connected = event->wValue;
1132 
1133 		printk(KERN_INFO KBUILD_MODNAME ": %s: network connection:"
1134 			" %sconnected\n",
1135 			ctx->netdev->name, ctx->connected ? "" : "dis");
1136 
1137 		if (ctx->connected)
1138 			netif_carrier_on(dev->net);
1139 		else {
1140 			netif_carrier_off(dev->net);
1141 			ctx->tx_speed = ctx->rx_speed = 0;
1142 		}
1143 		break;
1144 
1145 	case USB_CDC_NOTIFY_SPEED_CHANGE:
1146 		if (urb->actual_length < (sizeof(*event) +
1147 					sizeof(struct usb_cdc_speed_change)))
1148 			set_bit(EVENT_STS_SPLIT, &dev->flags);
1149 		else
1150 			cdc_ncm_speed_change(ctx,
1151 				(struct usb_cdc_speed_change *) &event[1]);
1152 		break;
1153 
1154 	default:
1155 		dev_err(&dev->udev->dev, "NCM: unexpected "
1156 			"notification 0x%02x!\n", event->bNotificationType);
1157 		break;
1158 	}
1159 }
1160 
cdc_ncm_check_connect(struct usbnet * dev)1161 static int cdc_ncm_check_connect(struct usbnet *dev)
1162 {
1163 	struct cdc_ncm_ctx *ctx;
1164 
1165 	ctx = (struct cdc_ncm_ctx *)dev->data[0];
1166 	if (ctx == NULL)
1167 		return 1;	/* disconnected */
1168 
1169 	return !ctx->connected;
1170 }
1171 
1172 static int
cdc_ncm_probe(struct usb_interface * udev,const struct usb_device_id * prod)1173 cdc_ncm_probe(struct usb_interface *udev, const struct usb_device_id *prod)
1174 {
1175 	return usbnet_probe(udev, prod);
1176 }
1177 
cdc_ncm_disconnect(struct usb_interface * intf)1178 static void cdc_ncm_disconnect(struct usb_interface *intf)
1179 {
1180 	struct usbnet *dev = usb_get_intfdata(intf);
1181 
1182 	if (dev == NULL)
1183 		return;		/* already disconnected */
1184 
1185 	usbnet_disconnect(intf);
1186 }
1187 
cdc_ncm_manage_power(struct usbnet * dev,int status)1188 static int cdc_ncm_manage_power(struct usbnet *dev, int status)
1189 {
1190 	dev->intf->needs_remote_wakeup = status;
1191 	return 0;
1192 }
1193 
1194 static const struct driver_info cdc_ncm_info = {
1195 	.description = "CDC NCM",
1196 	.flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET,
1197 	.bind = cdc_ncm_bind,
1198 	.unbind = cdc_ncm_unbind,
1199 	.check_connect = cdc_ncm_check_connect,
1200 	.manage_power = cdc_ncm_manage_power,
1201 	.status = cdc_ncm_status,
1202 	.rx_fixup = cdc_ncm_rx_fixup,
1203 	.tx_fixup = cdc_ncm_tx_fixup,
1204 };
1205 
1206 static struct usb_driver cdc_ncm_driver = {
1207 	.name = "cdc_ncm",
1208 	.id_table = cdc_devs,
1209 	.probe = cdc_ncm_probe,
1210 	.disconnect = cdc_ncm_disconnect,
1211 	.suspend = usbnet_suspend,
1212 	.resume = usbnet_resume,
1213 	.reset_resume =	usbnet_resume,
1214 	.supports_autosuspend = 1,
1215 };
1216 
1217 static const struct ethtool_ops cdc_ncm_ethtool_ops = {
1218 	.get_drvinfo = cdc_ncm_get_drvinfo,
1219 	.get_link = usbnet_get_link,
1220 	.get_msglevel = usbnet_get_msglevel,
1221 	.set_msglevel = usbnet_set_msglevel,
1222 	.get_settings = usbnet_get_settings,
1223 	.set_settings = usbnet_set_settings,
1224 	.nway_reset = usbnet_nway_reset,
1225 };
1226 
1227 module_usb_driver(cdc_ncm_driver);
1228 
1229 MODULE_AUTHOR("Hans Petter Selasky");
1230 MODULE_DESCRIPTION("USB CDC NCM host driver");
1231 MODULE_LICENSE("Dual BSD/GPL");
1232