xref: /linux/drivers/usb/core/sysfs.c (revision 5a0e3ad6af8660be21ca98a971cd00f331318c05)
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 
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
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
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
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
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
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
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
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
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
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
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
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 const char power_group[] = "power";
237 
238 static ssize_t
239 show_persist(struct device *dev, struct device_attribute *attr, char *buf)
240 {
241 	struct usb_device *udev = to_usb_device(dev);
242 
243 	return sprintf(buf, "%d\n", udev->persist_enabled);
244 }
245 
246 static ssize_t
247 set_persist(struct device *dev, struct device_attribute *attr,
248 		const char *buf, size_t count)
249 {
250 	struct usb_device *udev = to_usb_device(dev);
251 	int value;
252 
253 	/* Hubs are always enabled for USB_PERSIST */
254 	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
255 		return -EPERM;
256 
257 	if (sscanf(buf, "%d", &value) != 1)
258 		return -EINVAL;
259 
260 	usb_lock_device(udev);
261 	udev->persist_enabled = !!value;
262 	usb_unlock_device(udev);
263 	return count;
264 }
265 
266 static DEVICE_ATTR(persist, S_IRUGO | S_IWUSR, show_persist, set_persist);
267 
268 static int add_persist_attributes(struct device *dev)
269 {
270 	int rc = 0;
271 
272 	if (is_usb_device(dev)) {
273 		struct usb_device *udev = to_usb_device(dev);
274 
275 		/* Hubs are automatically enabled for USB_PERSIST,
276 		 * no point in creating the attribute file.
277 		 */
278 		if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
279 			rc = sysfs_add_file_to_group(&dev->kobj,
280 					&dev_attr_persist.attr,
281 					power_group);
282 	}
283 	return rc;
284 }
285 
286 static void remove_persist_attributes(struct device *dev)
287 {
288 	sysfs_remove_file_from_group(&dev->kobj,
289 			&dev_attr_persist.attr,
290 			power_group);
291 }
292 #else
293 
294 #define add_persist_attributes(dev)	0
295 #define remove_persist_attributes(dev)	do {} while (0)
296 
297 #endif	/* CONFIG_PM */
298 
299 #ifdef	CONFIG_USB_SUSPEND
300 
301 static ssize_t
302 show_connected_duration(struct device *dev, struct device_attribute *attr,
303 		char *buf)
304 {
305 	struct usb_device *udev = to_usb_device(dev);
306 
307 	return sprintf(buf, "%u\n",
308 			jiffies_to_msecs(jiffies - udev->connect_time));
309 }
310 
311 static DEVICE_ATTR(connected_duration, S_IRUGO, show_connected_duration, NULL);
312 
313 /*
314  * If the device is resumed, the last time the device was suspended has
315  * been pre-subtracted from active_duration.  We add the current time to
316  * get the duration that the device was actually active.
317  *
318  * If the device is suspended, the active_duration is up-to-date.
319  */
320 static ssize_t
321 show_active_duration(struct device *dev, struct device_attribute *attr,
322 		char *buf)
323 {
324 	struct usb_device *udev = to_usb_device(dev);
325 	int duration;
326 
327 	if (udev->state != USB_STATE_SUSPENDED)
328 		duration = jiffies_to_msecs(jiffies + udev->active_duration);
329 	else
330 		duration = jiffies_to_msecs(udev->active_duration);
331 	return sprintf(buf, "%u\n", duration);
332 }
333 
334 static DEVICE_ATTR(active_duration, S_IRUGO, show_active_duration, NULL);
335 
336 static ssize_t
337 show_autosuspend(struct device *dev, struct device_attribute *attr, char *buf)
338 {
339 	struct usb_device *udev = to_usb_device(dev);
340 
341 	return sprintf(buf, "%d\n", udev->autosuspend_delay / HZ);
342 }
343 
344 static ssize_t
345 set_autosuspend(struct device *dev, struct device_attribute *attr,
346 		const char *buf, size_t count)
347 {
348 	struct usb_device *udev = to_usb_device(dev);
349 	int value, old_delay;
350 	int rc;
351 
352 	if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/HZ ||
353 			value <= - INT_MAX/HZ)
354 		return -EINVAL;
355 	value *= HZ;
356 
357 	usb_lock_device(udev);
358 	old_delay = udev->autosuspend_delay;
359 	udev->autosuspend_delay = value;
360 
361 	if (old_delay < 0) {	/* Autosuspend wasn't allowed */
362 		if (value >= 0)
363 			usb_autosuspend_device(udev);
364 	} else {		/* Autosuspend was allowed */
365 		if (value < 0) {
366 			rc = usb_autoresume_device(udev);
367 			if (rc < 0) {
368 				count = rc;
369 				udev->autosuspend_delay = old_delay;
370 			}
371 		} else {
372 			usb_try_autosuspend_device(udev);
373 		}
374 	}
375 
376 	usb_unlock_device(udev);
377 	return count;
378 }
379 
380 static DEVICE_ATTR(autosuspend, S_IRUGO | S_IWUSR,
381 		show_autosuspend, set_autosuspend);
382 
383 static const char on_string[] = "on";
384 static const char auto_string[] = "auto";
385 
386 static ssize_t
387 show_level(struct device *dev, struct device_attribute *attr, char *buf)
388 {
389 	struct usb_device *udev = to_usb_device(dev);
390 	const char *p = auto_string;
391 
392 	if (udev->state != USB_STATE_SUSPENDED && udev->autosuspend_disabled)
393 		p = on_string;
394 	return sprintf(buf, "%s\n", p);
395 }
396 
397 static ssize_t
398 set_level(struct device *dev, struct device_attribute *attr,
399 		const char *buf, size_t count)
400 {
401 	struct usb_device *udev = to_usb_device(dev);
402 	int len = count;
403 	char *cp;
404 	int rc;
405 
406 	cp = memchr(buf, '\n', count);
407 	if (cp)
408 		len = cp - buf;
409 
410 	usb_lock_device(udev);
411 
412 	if (len == sizeof on_string - 1 &&
413 			strncmp(buf, on_string, len) == 0)
414 		rc = usb_disable_autosuspend(udev);
415 
416 	else if (len == sizeof auto_string - 1 &&
417 			strncmp(buf, auto_string, len) == 0)
418 		rc = usb_enable_autosuspend(udev);
419 
420 	else
421 		rc = -EINVAL;
422 
423 	usb_unlock_device(udev);
424 	return (rc < 0 ? rc : count);
425 }
426 
427 static DEVICE_ATTR(level, S_IRUGO | S_IWUSR, show_level, set_level);
428 
429 static int add_power_attributes(struct device *dev)
430 {
431 	int rc = 0;
432 
433 	if (is_usb_device(dev)) {
434 		rc = sysfs_add_file_to_group(&dev->kobj,
435 				&dev_attr_autosuspend.attr,
436 				power_group);
437 		if (rc == 0)
438 			rc = sysfs_add_file_to_group(&dev->kobj,
439 					&dev_attr_level.attr,
440 					power_group);
441 		if (rc == 0)
442 			rc = sysfs_add_file_to_group(&dev->kobj,
443 					&dev_attr_connected_duration.attr,
444 					power_group);
445 		if (rc == 0)
446 			rc = sysfs_add_file_to_group(&dev->kobj,
447 					&dev_attr_active_duration.attr,
448 					power_group);
449 	}
450 	return rc;
451 }
452 
453 static void remove_power_attributes(struct device *dev)
454 {
455 	sysfs_remove_file_from_group(&dev->kobj,
456 			&dev_attr_active_duration.attr,
457 			power_group);
458 	sysfs_remove_file_from_group(&dev->kobj,
459 			&dev_attr_connected_duration.attr,
460 			power_group);
461 	sysfs_remove_file_from_group(&dev->kobj,
462 			&dev_attr_level.attr,
463 			power_group);
464 	sysfs_remove_file_from_group(&dev->kobj,
465 			&dev_attr_autosuspend.attr,
466 			power_group);
467 }
468 
469 #else
470 
471 #define add_power_attributes(dev)	0
472 #define remove_power_attributes(dev)	do {} while (0)
473 
474 #endif	/* CONFIG_USB_SUSPEND */
475 
476 
477 /* Descriptor fields */
478 #define usb_descriptor_attr_le16(field, format_string)			\
479 static ssize_t								\
480 show_##field(struct device *dev, struct device_attribute *attr,	\
481 		char *buf)						\
482 {									\
483 	struct usb_device *udev;					\
484 									\
485 	udev = to_usb_device(dev);					\
486 	return sprintf(buf, format_string, 				\
487 			le16_to_cpu(udev->descriptor.field));		\
488 }									\
489 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
490 
491 usb_descriptor_attr_le16(idVendor, "%04x\n")
492 usb_descriptor_attr_le16(idProduct, "%04x\n")
493 usb_descriptor_attr_le16(bcdDevice, "%04x\n")
494 
495 #define usb_descriptor_attr(field, format_string)			\
496 static ssize_t								\
497 show_##field(struct device *dev, struct device_attribute *attr,	\
498 		char *buf)						\
499 {									\
500 	struct usb_device *udev;					\
501 									\
502 	udev = to_usb_device(dev);					\
503 	return sprintf(buf, format_string, udev->descriptor.field);	\
504 }									\
505 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
506 
507 usb_descriptor_attr(bDeviceClass, "%02x\n")
508 usb_descriptor_attr(bDeviceSubClass, "%02x\n")
509 usb_descriptor_attr(bDeviceProtocol, "%02x\n")
510 usb_descriptor_attr(bNumConfigurations, "%d\n")
511 usb_descriptor_attr(bMaxPacketSize0, "%d\n")
512 
513 
514 
515 /* show if the device is authorized (1) or not (0) */
516 static ssize_t usb_dev_authorized_show(struct device *dev,
517 				       struct device_attribute *attr,
518 				       char *buf)
519 {
520 	struct usb_device *usb_dev = to_usb_device(dev);
521 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
522 }
523 
524 
525 /*
526  * Authorize a device to be used in the system
527  *
528  * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
529  */
530 static ssize_t usb_dev_authorized_store(struct device *dev,
531 					struct device_attribute *attr,
532 					const char *buf, size_t size)
533 {
534 	ssize_t result;
535 	struct usb_device *usb_dev = to_usb_device(dev);
536 	unsigned val;
537 	result = sscanf(buf, "%u\n", &val);
538 	if (result != 1)
539 		result = -EINVAL;
540 	else if (val == 0)
541 		result = usb_deauthorize_device(usb_dev);
542 	else
543 		result = usb_authorize_device(usb_dev);
544 	return result < 0? result : size;
545 }
546 
547 static DEVICE_ATTR(authorized, 0644,
548 	    usb_dev_authorized_show, usb_dev_authorized_store);
549 
550 /* "Safely remove a device" */
551 static ssize_t usb_remove_store(struct device *dev,
552 		struct device_attribute *attr,
553 		const char *buf, size_t count)
554 {
555 	struct usb_device *udev = to_usb_device(dev);
556 	int rc = 0;
557 
558 	usb_lock_device(udev);
559 	if (udev->state != USB_STATE_NOTATTACHED) {
560 
561 		/* To avoid races, first unconfigure and then remove */
562 		usb_set_configuration(udev, -1);
563 		rc = usb_remove_device(udev);
564 	}
565 	if (rc == 0)
566 		rc = count;
567 	usb_unlock_device(udev);
568 	return rc;
569 }
570 static DEVICE_ATTR(remove, 0200, NULL, usb_remove_store);
571 
572 
573 static struct attribute *dev_attrs[] = {
574 	/* current configuration's attributes */
575 	&dev_attr_configuration.attr,
576 	&dev_attr_bNumInterfaces.attr,
577 	&dev_attr_bConfigurationValue.attr,
578 	&dev_attr_bmAttributes.attr,
579 	&dev_attr_bMaxPower.attr,
580 	/* device attributes */
581 	&dev_attr_urbnum.attr,
582 	&dev_attr_idVendor.attr,
583 	&dev_attr_idProduct.attr,
584 	&dev_attr_bcdDevice.attr,
585 	&dev_attr_bDeviceClass.attr,
586 	&dev_attr_bDeviceSubClass.attr,
587 	&dev_attr_bDeviceProtocol.attr,
588 	&dev_attr_bNumConfigurations.attr,
589 	&dev_attr_bMaxPacketSize0.attr,
590 	&dev_attr_speed.attr,
591 	&dev_attr_busnum.attr,
592 	&dev_attr_devnum.attr,
593 	&dev_attr_devpath.attr,
594 	&dev_attr_version.attr,
595 	&dev_attr_maxchild.attr,
596 	&dev_attr_quirks.attr,
597 	&dev_attr_avoid_reset_quirk.attr,
598 	&dev_attr_authorized.attr,
599 	&dev_attr_remove.attr,
600 	NULL,
601 };
602 static struct attribute_group dev_attr_grp = {
603 	.attrs = dev_attrs,
604 };
605 
606 /* When modifying this list, be sure to modify dev_string_attrs_are_visible()
607  * accordingly.
608  */
609 static struct attribute *dev_string_attrs[] = {
610 	&dev_attr_manufacturer.attr,
611 	&dev_attr_product.attr,
612 	&dev_attr_serial.attr,
613 	NULL
614 };
615 
616 static mode_t dev_string_attrs_are_visible(struct kobject *kobj,
617 		struct attribute *a, int n)
618 {
619 	struct device *dev = container_of(kobj, struct device, kobj);
620 	struct usb_device *udev = to_usb_device(dev);
621 
622 	if (a == &dev_attr_manufacturer.attr) {
623 		if (udev->manufacturer == NULL)
624 			return 0;
625 	} else if (a == &dev_attr_product.attr) {
626 		if (udev->product == NULL)
627 			return 0;
628 	} else if (a == &dev_attr_serial.attr) {
629 		if (udev->serial == NULL)
630 			return 0;
631 	}
632 	return a->mode;
633 }
634 
635 static struct attribute_group dev_string_attr_grp = {
636 	.attrs =	dev_string_attrs,
637 	.is_visible =	dev_string_attrs_are_visible,
638 };
639 
640 const struct attribute_group *usb_device_groups[] = {
641 	&dev_attr_grp,
642 	&dev_string_attr_grp,
643 	NULL
644 };
645 
646 /* Binary descriptors */
647 
648 static ssize_t
649 read_descriptors(struct kobject *kobj, struct bin_attribute *attr,
650 		char *buf, loff_t off, size_t count)
651 {
652 	struct device *dev = container_of(kobj, struct device, kobj);
653 	struct usb_device *udev = to_usb_device(dev);
654 	size_t nleft = count;
655 	size_t srclen, n;
656 	int cfgno;
657 	void *src;
658 
659 	/* The binary attribute begins with the device descriptor.
660 	 * Following that are the raw descriptor entries for all the
661 	 * configurations (config plus subsidiary descriptors).
662 	 */
663 	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
664 			nleft > 0; ++cfgno) {
665 		if (cfgno < 0) {
666 			src = &udev->descriptor;
667 			srclen = sizeof(struct usb_device_descriptor);
668 		} else {
669 			src = udev->rawdescriptors[cfgno];
670 			srclen = __le16_to_cpu(udev->config[cfgno].desc.
671 					wTotalLength);
672 		}
673 		if (off < srclen) {
674 			n = min(nleft, srclen - (size_t) off);
675 			memcpy(buf, src + off, n);
676 			nleft -= n;
677 			buf += n;
678 			off = 0;
679 		} else {
680 			off -= srclen;
681 		}
682 	}
683 	return count - nleft;
684 }
685 
686 static struct bin_attribute dev_bin_attr_descriptors = {
687 	.attr = {.name = "descriptors", .mode = 0444},
688 	.read = read_descriptors,
689 	.size = 18 + 65535,	/* dev descr + max-size raw descriptor */
690 };
691 
692 int usb_create_sysfs_dev_files(struct usb_device *udev)
693 {
694 	struct device *dev = &udev->dev;
695 	int retval;
696 
697 	retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
698 	if (retval)
699 		goto error;
700 
701 	retval = add_persist_attributes(dev);
702 	if (retval)
703 		goto error;
704 
705 	retval = add_power_attributes(dev);
706 	if (retval)
707 		goto error;
708 	return retval;
709 error:
710 	usb_remove_sysfs_dev_files(udev);
711 	return retval;
712 }
713 
714 void usb_remove_sysfs_dev_files(struct usb_device *udev)
715 {
716 	struct device *dev = &udev->dev;
717 
718 	remove_power_attributes(dev);
719 	remove_persist_attributes(dev);
720 	device_remove_bin_file(dev, &dev_bin_attr_descriptors);
721 }
722 
723 /* Interface Accociation Descriptor fields */
724 #define usb_intf_assoc_attr(field, format_string)			\
725 static ssize_t								\
726 show_iad_##field(struct device *dev, struct device_attribute *attr,	\
727 		char *buf)						\
728 {									\
729 	struct usb_interface *intf = to_usb_interface(dev);		\
730 									\
731 	return sprintf(buf, format_string,				\
732 			intf->intf_assoc->field); 			\
733 }									\
734 static DEVICE_ATTR(iad_##field, S_IRUGO, show_iad_##field, NULL);
735 
736 usb_intf_assoc_attr(bFirstInterface, "%02x\n")
737 usb_intf_assoc_attr(bInterfaceCount, "%02d\n")
738 usb_intf_assoc_attr(bFunctionClass, "%02x\n")
739 usb_intf_assoc_attr(bFunctionSubClass, "%02x\n")
740 usb_intf_assoc_attr(bFunctionProtocol, "%02x\n")
741 
742 /* Interface fields */
743 #define usb_intf_attr(field, format_string)				\
744 static ssize_t								\
745 show_##field(struct device *dev, struct device_attribute *attr,	\
746 		char *buf)						\
747 {									\
748 	struct usb_interface *intf = to_usb_interface(dev);		\
749 									\
750 	return sprintf(buf, format_string,				\
751 			intf->cur_altsetting->desc.field); 		\
752 }									\
753 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
754 
755 usb_intf_attr(bInterfaceNumber, "%02x\n")
756 usb_intf_attr(bAlternateSetting, "%2d\n")
757 usb_intf_attr(bNumEndpoints, "%02x\n")
758 usb_intf_attr(bInterfaceClass, "%02x\n")
759 usb_intf_attr(bInterfaceSubClass, "%02x\n")
760 usb_intf_attr(bInterfaceProtocol, "%02x\n")
761 
762 static ssize_t show_interface_string(struct device *dev,
763 		struct device_attribute *attr, char *buf)
764 {
765 	struct usb_interface *intf;
766 	char *string;
767 
768 	intf = to_usb_interface(dev);
769 	string = intf->cur_altsetting->string;
770 	barrier();		/* The altsetting might change! */
771 
772 	if (!string)
773 		return 0;
774 	return sprintf(buf, "%s\n", string);
775 }
776 static DEVICE_ATTR(interface, S_IRUGO, show_interface_string, NULL);
777 
778 static ssize_t show_modalias(struct device *dev,
779 		struct device_attribute *attr, char *buf)
780 {
781 	struct usb_interface *intf;
782 	struct usb_device *udev;
783 	struct usb_host_interface *alt;
784 
785 	intf = to_usb_interface(dev);
786 	udev = interface_to_usbdev(intf);
787 	alt = intf->cur_altsetting;
788 
789 	return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
790 			"ic%02Xisc%02Xip%02X\n",
791 			le16_to_cpu(udev->descriptor.idVendor),
792 			le16_to_cpu(udev->descriptor.idProduct),
793 			le16_to_cpu(udev->descriptor.bcdDevice),
794 			udev->descriptor.bDeviceClass,
795 			udev->descriptor.bDeviceSubClass,
796 			udev->descriptor.bDeviceProtocol,
797 			alt->desc.bInterfaceClass,
798 			alt->desc.bInterfaceSubClass,
799 			alt->desc.bInterfaceProtocol);
800 }
801 static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);
802 
803 static ssize_t show_supports_autosuspend(struct device *dev,
804 		struct device_attribute *attr, char *buf)
805 {
806 	struct usb_interface *intf;
807 	struct usb_device *udev;
808 	int ret;
809 
810 	intf = to_usb_interface(dev);
811 	udev = interface_to_usbdev(intf);
812 
813 	usb_lock_device(udev);
814 	/* Devices will be autosuspended even when an interface isn't claimed */
815 	if (!intf->dev.driver ||
816 			to_usb_driver(intf->dev.driver)->supports_autosuspend)
817 		ret = sprintf(buf, "%u\n", 1);
818 	else
819 		ret = sprintf(buf, "%u\n", 0);
820 	usb_unlock_device(udev);
821 
822 	return ret;
823 }
824 static DEVICE_ATTR(supports_autosuspend, S_IRUGO, show_supports_autosuspend, NULL);
825 
826 static struct attribute *intf_attrs[] = {
827 	&dev_attr_bInterfaceNumber.attr,
828 	&dev_attr_bAlternateSetting.attr,
829 	&dev_attr_bNumEndpoints.attr,
830 	&dev_attr_bInterfaceClass.attr,
831 	&dev_attr_bInterfaceSubClass.attr,
832 	&dev_attr_bInterfaceProtocol.attr,
833 	&dev_attr_modalias.attr,
834 	&dev_attr_supports_autosuspend.attr,
835 	NULL,
836 };
837 static struct attribute_group intf_attr_grp = {
838 	.attrs = intf_attrs,
839 };
840 
841 static struct attribute *intf_assoc_attrs[] = {
842 	&dev_attr_iad_bFirstInterface.attr,
843 	&dev_attr_iad_bInterfaceCount.attr,
844 	&dev_attr_iad_bFunctionClass.attr,
845 	&dev_attr_iad_bFunctionSubClass.attr,
846 	&dev_attr_iad_bFunctionProtocol.attr,
847 	NULL,
848 };
849 
850 static mode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
851 		struct attribute *a, int n)
852 {
853 	struct device *dev = container_of(kobj, struct device, kobj);
854 	struct usb_interface *intf = to_usb_interface(dev);
855 
856 	if (intf->intf_assoc == NULL)
857 		return 0;
858 	return a->mode;
859 }
860 
861 static struct attribute_group intf_assoc_attr_grp = {
862 	.attrs =	intf_assoc_attrs,
863 	.is_visible =	intf_assoc_attrs_are_visible,
864 };
865 
866 const struct attribute_group *usb_interface_groups[] = {
867 	&intf_attr_grp,
868 	&intf_assoc_attr_grp,
869 	NULL
870 };
871 
872 int usb_create_sysfs_intf_files(struct usb_interface *intf)
873 {
874 	struct usb_device *udev = interface_to_usbdev(intf);
875 	struct usb_host_interface *alt = intf->cur_altsetting;
876 	int retval;
877 
878 	if (intf->sysfs_files_created || intf->unregistering)
879 		return 0;
880 
881 	if (alt->string == NULL &&
882 			!(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
883 		alt->string = usb_cache_string(udev, alt->desc.iInterface);
884 	if (alt->string)
885 		retval = device_create_file(&intf->dev, &dev_attr_interface);
886 	intf->sysfs_files_created = 1;
887 	return 0;
888 }
889 
890 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
891 {
892 	if (!intf->sysfs_files_created)
893 		return;
894 
895 	device_remove_file(&intf->dev, &dev_attr_interface);
896 	intf->sysfs_files_created = 0;
897 }
898