1 /*
2  * drivers/usb/core/sysfs.c
3  *
4  * (C) Copyright 2002 David Brownell
5  * (C) Copyright 2002,2004 Greg Kroah-Hartman
6  * (C) Copyright 2002,2004 IBM Corp.
7  *
8  * All of the sysfs file attributes for usb devices and interfaces.
9  *
10  */
11 
12 
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/usb.h>
16 #include <linux/usb/quirks.h>
17 #include "usb.h"
18 
19 /* Active configuration fields */
20 #define usb_actconfig_show(field, multiplier, format_string)		\
21 static ssize_t  show_##field(struct device *dev,			\
22 		struct device_attribute *attr, char *buf)		\
23 {									\
24 	struct usb_device *udev;					\
25 	struct usb_host_config *actconfig;				\
26 									\
27 	udev = to_usb_device(dev);					\
28 	actconfig = udev->actconfig;					\
29 	if (actconfig)							\
30 		return sprintf(buf, format_string,			\
31 				actconfig->desc.field * multiplier);	\
32 	else								\
33 		return 0;						\
34 }									\
35 
36 #define usb_actconfig_attr(field, multiplier, format_string)		\
37 usb_actconfig_show(field, multiplier, format_string)			\
38 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
39 
40 usb_actconfig_attr(bNumInterfaces, 1, "%2d\n")
41 usb_actconfig_attr(bmAttributes, 1, "%2x\n")
42 usb_actconfig_attr(bMaxPower, 2, "%3dmA\n")
43 
show_configuration_string(struct device * dev,struct device_attribute * attr,char * buf)44 static ssize_t show_configuration_string(struct device *dev,
45 		struct device_attribute *attr, char *buf)
46 {
47 	struct usb_device *udev;
48 	struct usb_host_config *actconfig;
49 
50 	udev = to_usb_device(dev);
51 	actconfig = udev->actconfig;
52 	if ((!actconfig) || (!actconfig->string))
53 		return 0;
54 	return sprintf(buf, "%s\n", actconfig->string);
55 }
56 static DEVICE_ATTR(configuration, S_IRUGO, show_configuration_string, NULL);
57 
58 /* configuration value is always present, and r/w */
59 usb_actconfig_show(bConfigurationValue, 1, "%u\n");
60 
61 static ssize_t
set_bConfigurationValue(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)62 set_bConfigurationValue(struct device *dev, struct device_attribute *attr,
63 		const char *buf, size_t count)
64 {
65 	struct usb_device	*udev = to_usb_device(dev);
66 	int			config, value;
67 
68 	if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
69 		return -EINVAL;
70 	usb_lock_device(udev);
71 	value = usb_set_configuration(udev, config);
72 	usb_unlock_device(udev);
73 	return (value < 0) ? value : count;
74 }
75 
76 static DEVICE_ATTR(bConfigurationValue, S_IRUGO | S_IWUSR,
77 		show_bConfigurationValue, set_bConfigurationValue);
78 
79 /* String fields */
80 #define usb_string_attr(name)						\
81 static ssize_t  show_##name(struct device *dev,				\
82 		struct device_attribute *attr, char *buf)		\
83 {									\
84 	struct usb_device *udev;					\
85 	int retval;							\
86 									\
87 	udev = to_usb_device(dev);					\
88 	usb_lock_device(udev);						\
89 	retval = sprintf(buf, "%s\n", udev->name);			\
90 	usb_unlock_device(udev);					\
91 	return retval;							\
92 }									\
93 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL);
94 
95 usb_string_attr(product);
96 usb_string_attr(manufacturer);
97 usb_string_attr(serial);
98 
99 static ssize_t
show_speed(struct device * dev,struct device_attribute * attr,char * buf)100 show_speed(struct device *dev, struct device_attribute *attr, char *buf)
101 {
102 	struct usb_device *udev;
103 	char *speed;
104 
105 	udev = to_usb_device(dev);
106 
107 	switch (udev->speed) {
108 	case USB_SPEED_LOW:
109 		speed = "1.5";
110 		break;
111 	case USB_SPEED_UNKNOWN:
112 	case USB_SPEED_FULL:
113 		speed = "12";
114 		break;
115 	case USB_SPEED_HIGH:
116 		speed = "480";
117 		break;
118 	case USB_SPEED_WIRELESS:
119 		speed = "480";
120 		break;
121 	case USB_SPEED_SUPER:
122 		speed = "5000";
123 		break;
124 	default:
125 		speed = "unknown";
126 	}
127 	return sprintf(buf, "%s\n", speed);
128 }
129 static DEVICE_ATTR(speed, S_IRUGO, show_speed, NULL);
130 
131 static ssize_t
show_busnum(struct device * dev,struct device_attribute * attr,char * buf)132 show_busnum(struct device *dev, struct device_attribute *attr, char *buf)
133 {
134 	struct usb_device *udev;
135 
136 	udev = to_usb_device(dev);
137 	return sprintf(buf, "%d\n", udev->bus->busnum);
138 }
139 static DEVICE_ATTR(busnum, S_IRUGO, show_busnum, NULL);
140 
141 static ssize_t
show_devnum(struct device * dev,struct device_attribute * attr,char * buf)142 show_devnum(struct device *dev, struct device_attribute *attr, char *buf)
143 {
144 	struct usb_device *udev;
145 
146 	udev = to_usb_device(dev);
147 	return sprintf(buf, "%d\n", udev->devnum);
148 }
149 static DEVICE_ATTR(devnum, S_IRUGO, show_devnum, NULL);
150 
151 static ssize_t
show_devpath(struct device * dev,struct device_attribute * attr,char * buf)152 show_devpath(struct device *dev, struct device_attribute *attr, char *buf)
153 {
154 	struct usb_device *udev;
155 
156 	udev = to_usb_device(dev);
157 	return sprintf(buf, "%s\n", udev->devpath);
158 }
159 static DEVICE_ATTR(devpath, S_IRUGO, show_devpath, NULL);
160 
161 static ssize_t
show_version(struct device * dev,struct device_attribute * attr,char * buf)162 show_version(struct device *dev, struct device_attribute *attr, char *buf)
163 {
164 	struct usb_device *udev;
165 	u16 bcdUSB;
166 
167 	udev = to_usb_device(dev);
168 	bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
169 	return sprintf(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
170 }
171 static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
172 
173 static ssize_t
show_maxchild(struct device * dev,struct device_attribute * attr,char * buf)174 show_maxchild(struct device *dev, struct device_attribute *attr, char *buf)
175 {
176 	struct usb_device *udev;
177 
178 	udev = to_usb_device(dev);
179 	return sprintf(buf, "%d\n", udev->maxchild);
180 }
181 static DEVICE_ATTR(maxchild, S_IRUGO, show_maxchild, NULL);
182 
183 static ssize_t
show_quirks(struct device * dev,struct device_attribute * attr,char * buf)184 show_quirks(struct device *dev, struct device_attribute *attr, char *buf)
185 {
186 	struct usb_device *udev;
187 
188 	udev = to_usb_device(dev);
189 	return sprintf(buf, "0x%x\n", udev->quirks);
190 }
191 static DEVICE_ATTR(quirks, S_IRUGO, show_quirks, NULL);
192 
193 static ssize_t
show_avoid_reset_quirk(struct device * dev,struct device_attribute * attr,char * buf)194 show_avoid_reset_quirk(struct device *dev, struct device_attribute *attr, char *buf)
195 {
196 	struct usb_device *udev;
197 
198 	udev = to_usb_device(dev);
199 	return sprintf(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET_MORPHS));
200 }
201 
202 static ssize_t
set_avoid_reset_quirk(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)203 set_avoid_reset_quirk(struct device *dev, struct device_attribute *attr,
204 		const char *buf, size_t count)
205 {
206 	struct usb_device	*udev = to_usb_device(dev);
207 	int			config;
208 
209 	if (sscanf(buf, "%d", &config) != 1 || config < 0 || config > 1)
210 		return -EINVAL;
211 	usb_lock_device(udev);
212 	if (config)
213 		udev->quirks |= USB_QUIRK_RESET_MORPHS;
214 	else
215 		udev->quirks &= ~USB_QUIRK_RESET_MORPHS;
216 	usb_unlock_device(udev);
217 	return count;
218 }
219 
220 static DEVICE_ATTR(avoid_reset_quirk, S_IRUGO | S_IWUSR,
221 		show_avoid_reset_quirk, set_avoid_reset_quirk);
222 
223 static ssize_t
show_urbnum(struct device * dev,struct device_attribute * attr,char * buf)224 show_urbnum(struct device *dev, struct device_attribute *attr, char *buf)
225 {
226 	struct usb_device *udev;
227 
228 	udev = to_usb_device(dev);
229 	return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
230 }
231 static DEVICE_ATTR(urbnum, S_IRUGO, show_urbnum, NULL);
232 
233 
234 #ifdef	CONFIG_PM
235 
236 static ssize_t
show_persist(struct device * dev,struct device_attribute * attr,char * buf)237 show_persist(struct device *dev, struct device_attribute *attr, char *buf)
238 {
239 	struct usb_device *udev = to_usb_device(dev);
240 
241 	return sprintf(buf, "%d\n", udev->persist_enabled);
242 }
243 
244 static ssize_t
set_persist(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)245 set_persist(struct device *dev, struct device_attribute *attr,
246 		const char *buf, size_t count)
247 {
248 	struct usb_device *udev = to_usb_device(dev);
249 	int value;
250 
251 	/* Hubs are always enabled for USB_PERSIST */
252 	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
253 		return -EPERM;
254 
255 	if (sscanf(buf, "%d", &value) != 1)
256 		return -EINVAL;
257 
258 	usb_lock_device(udev);
259 	udev->persist_enabled = !!value;
260 	usb_unlock_device(udev);
261 	return count;
262 }
263 
264 static DEVICE_ATTR(persist, S_IRUGO | S_IWUSR, show_persist, set_persist);
265 
add_persist_attributes(struct device * dev)266 static int add_persist_attributes(struct device *dev)
267 {
268 	int rc = 0;
269 
270 	if (is_usb_device(dev)) {
271 		struct usb_device *udev = to_usb_device(dev);
272 
273 		/* Hubs are automatically enabled for USB_PERSIST,
274 		 * no point in creating the attribute file.
275 		 */
276 		if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
277 			rc = sysfs_add_file_to_group(&dev->kobj,
278 					&dev_attr_persist.attr,
279 					power_group_name);
280 	}
281 	return rc;
282 }
283 
remove_persist_attributes(struct device * dev)284 static void remove_persist_attributes(struct device *dev)
285 {
286 	sysfs_remove_file_from_group(&dev->kobj,
287 			&dev_attr_persist.attr,
288 			power_group_name);
289 }
290 #else
291 
292 #define add_persist_attributes(dev)	0
293 #define remove_persist_attributes(dev)	do {} while (0)
294 
295 #endif	/* CONFIG_PM */
296 
297 #ifdef	CONFIG_USB_SUSPEND
298 
299 static ssize_t
show_connected_duration(struct device * dev,struct device_attribute * attr,char * buf)300 show_connected_duration(struct device *dev, struct device_attribute *attr,
301 		char *buf)
302 {
303 	struct usb_device *udev = to_usb_device(dev);
304 
305 	return sprintf(buf, "%u\n",
306 			jiffies_to_msecs(jiffies - udev->connect_time));
307 }
308 
309 static DEVICE_ATTR(connected_duration, S_IRUGO, show_connected_duration, NULL);
310 
311 /*
312  * If the device is resumed, the last time the device was suspended has
313  * been pre-subtracted from active_duration.  We add the current time to
314  * get the duration that the device was actually active.
315  *
316  * If the device is suspended, the active_duration is up-to-date.
317  */
318 static ssize_t
show_active_duration(struct device * dev,struct device_attribute * attr,char * buf)319 show_active_duration(struct device *dev, struct device_attribute *attr,
320 		char *buf)
321 {
322 	struct usb_device *udev = to_usb_device(dev);
323 	int duration;
324 
325 	if (udev->state != USB_STATE_SUSPENDED)
326 		duration = jiffies_to_msecs(jiffies + udev->active_duration);
327 	else
328 		duration = jiffies_to_msecs(udev->active_duration);
329 	return sprintf(buf, "%u\n", duration);
330 }
331 
332 static DEVICE_ATTR(active_duration, S_IRUGO, show_active_duration, NULL);
333 
334 static ssize_t
show_autosuspend(struct device * dev,struct device_attribute * attr,char * buf)335 show_autosuspend(struct device *dev, struct device_attribute *attr, char *buf)
336 {
337 	return sprintf(buf, "%d\n", dev->power.autosuspend_delay / 1000);
338 }
339 
340 static ssize_t
set_autosuspend(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)341 set_autosuspend(struct device *dev, struct device_attribute *attr,
342 		const char *buf, size_t count)
343 {
344 	int value;
345 
346 	if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/1000 ||
347 			value <= -INT_MAX/1000)
348 		return -EINVAL;
349 
350 	pm_runtime_set_autosuspend_delay(dev, value * 1000);
351 	return count;
352 }
353 
354 static DEVICE_ATTR(autosuspend, S_IRUGO | S_IWUSR,
355 		show_autosuspend, set_autosuspend);
356 
357 static const char on_string[] = "on";
358 static const char auto_string[] = "auto";
359 
warn_level(void)360 static void warn_level(void) {
361 	static int level_warned;
362 
363 	if (!level_warned) {
364 		level_warned = 1;
365 		printk(KERN_WARNING "WARNING! power/level is deprecated; "
366 				"use power/control instead\n");
367 	}
368 }
369 
370 static ssize_t
show_level(struct device * dev,struct device_attribute * attr,char * buf)371 show_level(struct device *dev, struct device_attribute *attr, char *buf)
372 {
373 	struct usb_device *udev = to_usb_device(dev);
374 	const char *p = auto_string;
375 
376 	warn_level();
377 	if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
378 		p = on_string;
379 	return sprintf(buf, "%s\n", p);
380 }
381 
382 static ssize_t
set_level(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)383 set_level(struct device *dev, struct device_attribute *attr,
384 		const char *buf, size_t count)
385 {
386 	struct usb_device *udev = to_usb_device(dev);
387 	int len = count;
388 	char *cp;
389 	int rc = count;
390 
391 	warn_level();
392 	cp = memchr(buf, '\n', count);
393 	if (cp)
394 		len = cp - buf;
395 
396 	usb_lock_device(udev);
397 
398 	if (len == sizeof on_string - 1 &&
399 			strncmp(buf, on_string, len) == 0)
400 		usb_disable_autosuspend(udev);
401 
402 	else if (len == sizeof auto_string - 1 &&
403 			strncmp(buf, auto_string, len) == 0)
404 		usb_enable_autosuspend(udev);
405 
406 	else
407 		rc = -EINVAL;
408 
409 	usb_unlock_device(udev);
410 	return rc;
411 }
412 
413 static DEVICE_ATTR(level, S_IRUGO | S_IWUSR, show_level, set_level);
414 
415 static struct attribute *power_attrs[] = {
416 	&dev_attr_autosuspend.attr,
417 	&dev_attr_level.attr,
418 	&dev_attr_connected_duration.attr,
419 	&dev_attr_active_duration.attr,
420 	NULL,
421 };
422 static struct attribute_group power_attr_group = {
423 	.name	= power_group_name,
424 	.attrs	= power_attrs,
425 };
426 
add_power_attributes(struct device * dev)427 static int add_power_attributes(struct device *dev)
428 {
429 	int rc = 0;
430 
431 	if (is_usb_device(dev))
432 		rc = sysfs_merge_group(&dev->kobj, &power_attr_group);
433 	return rc;
434 }
435 
remove_power_attributes(struct device * dev)436 static void remove_power_attributes(struct device *dev)
437 {
438 	sysfs_unmerge_group(&dev->kobj, &power_attr_group);
439 }
440 
441 #else
442 
443 #define add_power_attributes(dev)	0
444 #define remove_power_attributes(dev)	do {} while (0)
445 
446 #endif	/* CONFIG_USB_SUSPEND */
447 
448 
449 /* Descriptor fields */
450 #define usb_descriptor_attr_le16(field, format_string)			\
451 static ssize_t								\
452 show_##field(struct device *dev, struct device_attribute *attr,	\
453 		char *buf)						\
454 {									\
455 	struct usb_device *udev;					\
456 									\
457 	udev = to_usb_device(dev);					\
458 	return sprintf(buf, format_string, 				\
459 			le16_to_cpu(udev->descriptor.field));		\
460 }									\
461 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
462 
463 usb_descriptor_attr_le16(idVendor, "%04x\n")
464 usb_descriptor_attr_le16(idProduct, "%04x\n")
465 usb_descriptor_attr_le16(bcdDevice, "%04x\n")
466 
467 #define usb_descriptor_attr(field, format_string)			\
468 static ssize_t								\
469 show_##field(struct device *dev, struct device_attribute *attr,	\
470 		char *buf)						\
471 {									\
472 	struct usb_device *udev;					\
473 									\
474 	udev = to_usb_device(dev);					\
475 	return sprintf(buf, format_string, udev->descriptor.field);	\
476 }									\
477 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
478 
479 usb_descriptor_attr(bDeviceClass, "%02x\n")
480 usb_descriptor_attr(bDeviceSubClass, "%02x\n")
481 usb_descriptor_attr(bDeviceProtocol, "%02x\n")
482 usb_descriptor_attr(bNumConfigurations, "%d\n")
483 usb_descriptor_attr(bMaxPacketSize0, "%d\n")
484 
485 
486 
487 /* show if the device is authorized (1) or not (0) */
usb_dev_authorized_show(struct device * dev,struct device_attribute * attr,char * buf)488 static ssize_t usb_dev_authorized_show(struct device *dev,
489 				       struct device_attribute *attr,
490 				       char *buf)
491 {
492 	struct usb_device *usb_dev = to_usb_device(dev);
493 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
494 }
495 
496 
497 /*
498  * Authorize a device to be used in the system
499  *
500  * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
501  */
usb_dev_authorized_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t size)502 static ssize_t usb_dev_authorized_store(struct device *dev,
503 					struct device_attribute *attr,
504 					const char *buf, size_t size)
505 {
506 	ssize_t result;
507 	struct usb_device *usb_dev = to_usb_device(dev);
508 	unsigned val;
509 	result = sscanf(buf, "%u\n", &val);
510 	if (result != 1)
511 		result = -EINVAL;
512 	else if (val == 0)
513 		result = usb_deauthorize_device(usb_dev);
514 	else
515 		result = usb_authorize_device(usb_dev);
516 	return result < 0? result : size;
517 }
518 
519 static DEVICE_ATTR(authorized, 0644,
520 	    usb_dev_authorized_show, usb_dev_authorized_store);
521 
522 /* "Safely remove a device" */
usb_remove_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)523 static ssize_t usb_remove_store(struct device *dev,
524 		struct device_attribute *attr,
525 		const char *buf, size_t count)
526 {
527 	struct usb_device *udev = to_usb_device(dev);
528 	int rc = 0;
529 
530 	usb_lock_device(udev);
531 	if (udev->state != USB_STATE_NOTATTACHED) {
532 
533 		/* To avoid races, first unconfigure and then remove */
534 		usb_set_configuration(udev, -1);
535 		rc = usb_remove_device(udev);
536 	}
537 	if (rc == 0)
538 		rc = count;
539 	usb_unlock_device(udev);
540 	return rc;
541 }
542 static DEVICE_ATTR(remove, 0200, NULL, usb_remove_store);
543 
544 
545 static struct attribute *dev_attrs[] = {
546 	/* current configuration's attributes */
547 	&dev_attr_configuration.attr,
548 	&dev_attr_bNumInterfaces.attr,
549 	&dev_attr_bConfigurationValue.attr,
550 	&dev_attr_bmAttributes.attr,
551 	&dev_attr_bMaxPower.attr,
552 	/* device attributes */
553 	&dev_attr_urbnum.attr,
554 	&dev_attr_idVendor.attr,
555 	&dev_attr_idProduct.attr,
556 	&dev_attr_bcdDevice.attr,
557 	&dev_attr_bDeviceClass.attr,
558 	&dev_attr_bDeviceSubClass.attr,
559 	&dev_attr_bDeviceProtocol.attr,
560 	&dev_attr_bNumConfigurations.attr,
561 	&dev_attr_bMaxPacketSize0.attr,
562 	&dev_attr_speed.attr,
563 	&dev_attr_busnum.attr,
564 	&dev_attr_devnum.attr,
565 	&dev_attr_devpath.attr,
566 	&dev_attr_version.attr,
567 	&dev_attr_maxchild.attr,
568 	&dev_attr_quirks.attr,
569 	&dev_attr_avoid_reset_quirk.attr,
570 	&dev_attr_authorized.attr,
571 	&dev_attr_remove.attr,
572 	NULL,
573 };
574 static struct attribute_group dev_attr_grp = {
575 	.attrs = dev_attrs,
576 };
577 
578 /* When modifying this list, be sure to modify dev_string_attrs_are_visible()
579  * accordingly.
580  */
581 static struct attribute *dev_string_attrs[] = {
582 	&dev_attr_manufacturer.attr,
583 	&dev_attr_product.attr,
584 	&dev_attr_serial.attr,
585 	NULL
586 };
587 
dev_string_attrs_are_visible(struct kobject * kobj,struct attribute * a,int n)588 static mode_t dev_string_attrs_are_visible(struct kobject *kobj,
589 		struct attribute *a, int n)
590 {
591 	struct device *dev = container_of(kobj, struct device, kobj);
592 	struct usb_device *udev = to_usb_device(dev);
593 
594 	if (a == &dev_attr_manufacturer.attr) {
595 		if (udev->manufacturer == NULL)
596 			return 0;
597 	} else if (a == &dev_attr_product.attr) {
598 		if (udev->product == NULL)
599 			return 0;
600 	} else if (a == &dev_attr_serial.attr) {
601 		if (udev->serial == NULL)
602 			return 0;
603 	}
604 	return a->mode;
605 }
606 
607 static struct attribute_group dev_string_attr_grp = {
608 	.attrs =	dev_string_attrs,
609 	.is_visible =	dev_string_attrs_are_visible,
610 };
611 
612 const struct attribute_group *usb_device_groups[] = {
613 	&dev_attr_grp,
614 	&dev_string_attr_grp,
615 	NULL
616 };
617 
618 /* Binary descriptors */
619 
620 static ssize_t
read_descriptors(struct file * filp,struct kobject * kobj,struct bin_attribute * attr,char * buf,loff_t off,size_t count)621 read_descriptors(struct file *filp, struct kobject *kobj,
622 		struct bin_attribute *attr,
623 		char *buf, loff_t off, size_t count)
624 {
625 	struct device *dev = container_of(kobj, struct device, kobj);
626 	struct usb_device *udev = to_usb_device(dev);
627 	size_t nleft = count;
628 	size_t srclen, n;
629 	int cfgno;
630 	void *src;
631 
632 	/* The binary attribute begins with the device descriptor.
633 	 * Following that are the raw descriptor entries for all the
634 	 * configurations (config plus subsidiary descriptors).
635 	 */
636 	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
637 			nleft > 0; ++cfgno) {
638 		if (cfgno < 0) {
639 			src = &udev->descriptor;
640 			srclen = sizeof(struct usb_device_descriptor);
641 		} else {
642 			src = udev->rawdescriptors[cfgno];
643 			srclen = __le16_to_cpu(udev->config[cfgno].desc.
644 					wTotalLength);
645 		}
646 		if (off < srclen) {
647 			n = min(nleft, srclen - (size_t) off);
648 			memcpy(buf, src + off, n);
649 			nleft -= n;
650 			buf += n;
651 			off = 0;
652 		} else {
653 			off -= srclen;
654 		}
655 	}
656 	return count - nleft;
657 }
658 
659 static struct bin_attribute dev_bin_attr_descriptors = {
660 	.attr = {.name = "descriptors", .mode = 0444},
661 	.read = read_descriptors,
662 	.size = 18 + 65535,	/* dev descr + max-size raw descriptor */
663 };
664 
usb_create_sysfs_dev_files(struct usb_device * udev)665 int usb_create_sysfs_dev_files(struct usb_device *udev)
666 {
667 	struct device *dev = &udev->dev;
668 	int retval;
669 
670 	retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
671 	if (retval)
672 		goto error;
673 
674 	retval = add_persist_attributes(dev);
675 	if (retval)
676 		goto error;
677 
678 	retval = add_power_attributes(dev);
679 	if (retval)
680 		goto error;
681 	return retval;
682 error:
683 	usb_remove_sysfs_dev_files(udev);
684 	return retval;
685 }
686 
usb_remove_sysfs_dev_files(struct usb_device * udev)687 void usb_remove_sysfs_dev_files(struct usb_device *udev)
688 {
689 	struct device *dev = &udev->dev;
690 
691 	remove_power_attributes(dev);
692 	remove_persist_attributes(dev);
693 	device_remove_bin_file(dev, &dev_bin_attr_descriptors);
694 }
695 
696 /* Interface Accociation Descriptor fields */
697 #define usb_intf_assoc_attr(field, format_string)			\
698 static ssize_t								\
699 show_iad_##field(struct device *dev, struct device_attribute *attr,	\
700 		char *buf)						\
701 {									\
702 	struct usb_interface *intf = to_usb_interface(dev);		\
703 									\
704 	return sprintf(buf, format_string,				\
705 			intf->intf_assoc->field); 			\
706 }									\
707 static DEVICE_ATTR(iad_##field, S_IRUGO, show_iad_##field, NULL);
708 
709 usb_intf_assoc_attr(bFirstInterface, "%02x\n")
710 usb_intf_assoc_attr(bInterfaceCount, "%02d\n")
711 usb_intf_assoc_attr(bFunctionClass, "%02x\n")
712 usb_intf_assoc_attr(bFunctionSubClass, "%02x\n")
713 usb_intf_assoc_attr(bFunctionProtocol, "%02x\n")
714 
715 /* Interface fields */
716 #define usb_intf_attr(field, format_string)				\
717 static ssize_t								\
718 show_##field(struct device *dev, struct device_attribute *attr,	\
719 		char *buf)						\
720 {									\
721 	struct usb_interface *intf = to_usb_interface(dev);		\
722 									\
723 	return sprintf(buf, format_string,				\
724 			intf->cur_altsetting->desc.field); 		\
725 }									\
726 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
727 
728 usb_intf_attr(bInterfaceNumber, "%02x\n")
729 usb_intf_attr(bAlternateSetting, "%2d\n")
730 usb_intf_attr(bNumEndpoints, "%02x\n")
731 usb_intf_attr(bInterfaceClass, "%02x\n")
732 usb_intf_attr(bInterfaceSubClass, "%02x\n")
733 usb_intf_attr(bInterfaceProtocol, "%02x\n")
734 
show_interface_string(struct device * dev,struct device_attribute * attr,char * buf)735 static ssize_t show_interface_string(struct device *dev,
736 		struct device_attribute *attr, char *buf)
737 {
738 	struct usb_interface *intf;
739 	char *string;
740 
741 	intf = to_usb_interface(dev);
742 	string = intf->cur_altsetting->string;
743 	barrier();		/* The altsetting might change! */
744 
745 	if (!string)
746 		return 0;
747 	return sprintf(buf, "%s\n", string);
748 }
749 static DEVICE_ATTR(interface, S_IRUGO, show_interface_string, NULL);
750 
show_modalias(struct device * dev,struct device_attribute * attr,char * buf)751 static ssize_t show_modalias(struct device *dev,
752 		struct device_attribute *attr, char *buf)
753 {
754 	struct usb_interface *intf;
755 	struct usb_device *udev;
756 	struct usb_host_interface *alt;
757 
758 	intf = to_usb_interface(dev);
759 	udev = interface_to_usbdev(intf);
760 	alt = intf->cur_altsetting;
761 
762 	return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
763 			"ic%02Xisc%02Xip%02X\n",
764 			le16_to_cpu(udev->descriptor.idVendor),
765 			le16_to_cpu(udev->descriptor.idProduct),
766 			le16_to_cpu(udev->descriptor.bcdDevice),
767 			udev->descriptor.bDeviceClass,
768 			udev->descriptor.bDeviceSubClass,
769 			udev->descriptor.bDeviceProtocol,
770 			alt->desc.bInterfaceClass,
771 			alt->desc.bInterfaceSubClass,
772 			alt->desc.bInterfaceProtocol);
773 }
774 static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);
775 
show_supports_autosuspend(struct device * dev,struct device_attribute * attr,char * buf)776 static ssize_t show_supports_autosuspend(struct device *dev,
777 		struct device_attribute *attr, char *buf)
778 {
779 	struct usb_interface *intf;
780 	struct usb_device *udev;
781 	int ret;
782 
783 	intf = to_usb_interface(dev);
784 	udev = interface_to_usbdev(intf);
785 
786 	usb_lock_device(udev);
787 	/* Devices will be autosuspended even when an interface isn't claimed */
788 	if (!intf->dev.driver ||
789 			to_usb_driver(intf->dev.driver)->supports_autosuspend)
790 		ret = sprintf(buf, "%u\n", 1);
791 	else
792 		ret = sprintf(buf, "%u\n", 0);
793 	usb_unlock_device(udev);
794 
795 	return ret;
796 }
797 static DEVICE_ATTR(supports_autosuspend, S_IRUGO, show_supports_autosuspend, NULL);
798 
799 static struct attribute *intf_attrs[] = {
800 	&dev_attr_bInterfaceNumber.attr,
801 	&dev_attr_bAlternateSetting.attr,
802 	&dev_attr_bNumEndpoints.attr,
803 	&dev_attr_bInterfaceClass.attr,
804 	&dev_attr_bInterfaceSubClass.attr,
805 	&dev_attr_bInterfaceProtocol.attr,
806 	&dev_attr_modalias.attr,
807 	&dev_attr_supports_autosuspend.attr,
808 	NULL,
809 };
810 static struct attribute_group intf_attr_grp = {
811 	.attrs = intf_attrs,
812 };
813 
814 static struct attribute *intf_assoc_attrs[] = {
815 	&dev_attr_iad_bFirstInterface.attr,
816 	&dev_attr_iad_bInterfaceCount.attr,
817 	&dev_attr_iad_bFunctionClass.attr,
818 	&dev_attr_iad_bFunctionSubClass.attr,
819 	&dev_attr_iad_bFunctionProtocol.attr,
820 	NULL,
821 };
822 
intf_assoc_attrs_are_visible(struct kobject * kobj,struct attribute * a,int n)823 static mode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
824 		struct attribute *a, int n)
825 {
826 	struct device *dev = container_of(kobj, struct device, kobj);
827 	struct usb_interface *intf = to_usb_interface(dev);
828 
829 	if (intf->intf_assoc == NULL)
830 		return 0;
831 	return a->mode;
832 }
833 
834 static struct attribute_group intf_assoc_attr_grp = {
835 	.attrs =	intf_assoc_attrs,
836 	.is_visible =	intf_assoc_attrs_are_visible,
837 };
838 
839 const struct attribute_group *usb_interface_groups[] = {
840 	&intf_attr_grp,
841 	&intf_assoc_attr_grp,
842 	NULL
843 };
844 
usb_create_sysfs_intf_files(struct usb_interface * intf)845 int usb_create_sysfs_intf_files(struct usb_interface *intf)
846 {
847 	struct usb_device *udev = interface_to_usbdev(intf);
848 	struct usb_host_interface *alt = intf->cur_altsetting;
849 	int retval;
850 
851 	if (intf->sysfs_files_created || intf->unregistering)
852 		return 0;
853 
854 	if (alt->string == NULL &&
855 			!(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
856 		alt->string = usb_cache_string(udev, alt->desc.iInterface);
857 	if (alt->string)
858 		retval = device_create_file(&intf->dev, &dev_attr_interface);
859 	intf->sysfs_files_created = 1;
860 	return 0;
861 }
862 
usb_remove_sysfs_intf_files(struct usb_interface * intf)863 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
864 {
865 	if (!intf->sysfs_files_created)
866 		return;
867 
868 	device_remove_file(&intf->dev, &dev_attr_interface);
869 	intf->sysfs_files_created = 0;
870 }
871