xref: /linux/drivers/usb/core/sysfs.c (revision 765532c8aaac624b5f8687af6d319c6a1138a257)
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 void warn_level(void) {
387 	static int level_warned;
388 
389 	if (!level_warned) {
390 		level_warned = 1;
391 		printk(KERN_WARNING "WARNING! power/level is deprecated; "
392 				"use power/control instead\n");
393 	}
394 }
395 
396 static ssize_t
397 show_level(struct device *dev, struct device_attribute *attr, char *buf)
398 {
399 	struct usb_device *udev = to_usb_device(dev);
400 	const char *p = auto_string;
401 
402 	warn_level();
403 	if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
404 		p = on_string;
405 	return sprintf(buf, "%s\n", p);
406 }
407 
408 static ssize_t
409 set_level(struct device *dev, struct device_attribute *attr,
410 		const char *buf, size_t count)
411 {
412 	struct usb_device *udev = to_usb_device(dev);
413 	int len = count;
414 	char *cp;
415 	int rc = count;
416 
417 	warn_level();
418 	cp = memchr(buf, '\n', count);
419 	if (cp)
420 		len = cp - buf;
421 
422 	usb_lock_device(udev);
423 
424 	if (len == sizeof on_string - 1 &&
425 			strncmp(buf, on_string, len) == 0)
426 		usb_disable_autosuspend(udev);
427 
428 	else if (len == sizeof auto_string - 1 &&
429 			strncmp(buf, auto_string, len) == 0)
430 		usb_enable_autosuspend(udev);
431 
432 	else
433 		rc = -EINVAL;
434 
435 	usb_unlock_device(udev);
436 	return rc;
437 }
438 
439 static DEVICE_ATTR(level, S_IRUGO | S_IWUSR, show_level, set_level);
440 
441 static int add_power_attributes(struct device *dev)
442 {
443 	int rc = 0;
444 
445 	if (is_usb_device(dev)) {
446 		rc = sysfs_add_file_to_group(&dev->kobj,
447 				&dev_attr_autosuspend.attr,
448 				power_group);
449 		if (rc == 0)
450 			rc = sysfs_add_file_to_group(&dev->kobj,
451 					&dev_attr_level.attr,
452 					power_group);
453 		if (rc == 0)
454 			rc = sysfs_add_file_to_group(&dev->kobj,
455 					&dev_attr_connected_duration.attr,
456 					power_group);
457 		if (rc == 0)
458 			rc = sysfs_add_file_to_group(&dev->kobj,
459 					&dev_attr_active_duration.attr,
460 					power_group);
461 	}
462 	return rc;
463 }
464 
465 static void remove_power_attributes(struct device *dev)
466 {
467 	sysfs_remove_file_from_group(&dev->kobj,
468 			&dev_attr_active_duration.attr,
469 			power_group);
470 	sysfs_remove_file_from_group(&dev->kobj,
471 			&dev_attr_connected_duration.attr,
472 			power_group);
473 	sysfs_remove_file_from_group(&dev->kobj,
474 			&dev_attr_level.attr,
475 			power_group);
476 	sysfs_remove_file_from_group(&dev->kobj,
477 			&dev_attr_autosuspend.attr,
478 			power_group);
479 }
480 
481 #else
482 
483 #define add_power_attributes(dev)	0
484 #define remove_power_attributes(dev)	do {} while (0)
485 
486 #endif	/* CONFIG_USB_SUSPEND */
487 
488 
489 /* Descriptor fields */
490 #define usb_descriptor_attr_le16(field, format_string)			\
491 static ssize_t								\
492 show_##field(struct device *dev, struct device_attribute *attr,	\
493 		char *buf)						\
494 {									\
495 	struct usb_device *udev;					\
496 									\
497 	udev = to_usb_device(dev);					\
498 	return sprintf(buf, format_string, 				\
499 			le16_to_cpu(udev->descriptor.field));		\
500 }									\
501 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
502 
503 usb_descriptor_attr_le16(idVendor, "%04x\n")
504 usb_descriptor_attr_le16(idProduct, "%04x\n")
505 usb_descriptor_attr_le16(bcdDevice, "%04x\n")
506 
507 #define usb_descriptor_attr(field, format_string)			\
508 static ssize_t								\
509 show_##field(struct device *dev, struct device_attribute *attr,	\
510 		char *buf)						\
511 {									\
512 	struct usb_device *udev;					\
513 									\
514 	udev = to_usb_device(dev);					\
515 	return sprintf(buf, format_string, udev->descriptor.field);	\
516 }									\
517 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
518 
519 usb_descriptor_attr(bDeviceClass, "%02x\n")
520 usb_descriptor_attr(bDeviceSubClass, "%02x\n")
521 usb_descriptor_attr(bDeviceProtocol, "%02x\n")
522 usb_descriptor_attr(bNumConfigurations, "%d\n")
523 usb_descriptor_attr(bMaxPacketSize0, "%d\n")
524 
525 
526 
527 /* show if the device is authorized (1) or not (0) */
528 static ssize_t usb_dev_authorized_show(struct device *dev,
529 				       struct device_attribute *attr,
530 				       char *buf)
531 {
532 	struct usb_device *usb_dev = to_usb_device(dev);
533 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
534 }
535 
536 
537 /*
538  * Authorize a device to be used in the system
539  *
540  * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
541  */
542 static ssize_t usb_dev_authorized_store(struct device *dev,
543 					struct device_attribute *attr,
544 					const char *buf, size_t size)
545 {
546 	ssize_t result;
547 	struct usb_device *usb_dev = to_usb_device(dev);
548 	unsigned val;
549 	result = sscanf(buf, "%u\n", &val);
550 	if (result != 1)
551 		result = -EINVAL;
552 	else if (val == 0)
553 		result = usb_deauthorize_device(usb_dev);
554 	else
555 		result = usb_authorize_device(usb_dev);
556 	return result < 0? result : size;
557 }
558 
559 static DEVICE_ATTR(authorized, 0644,
560 	    usb_dev_authorized_show, usb_dev_authorized_store);
561 
562 /* "Safely remove a device" */
563 static ssize_t usb_remove_store(struct device *dev,
564 		struct device_attribute *attr,
565 		const char *buf, size_t count)
566 {
567 	struct usb_device *udev = to_usb_device(dev);
568 	int rc = 0;
569 
570 	usb_lock_device(udev);
571 	if (udev->state != USB_STATE_NOTATTACHED) {
572 
573 		/* To avoid races, first unconfigure and then remove */
574 		usb_set_configuration(udev, -1);
575 		rc = usb_remove_device(udev);
576 	}
577 	if (rc == 0)
578 		rc = count;
579 	usb_unlock_device(udev);
580 	return rc;
581 }
582 static DEVICE_ATTR(remove, 0200, NULL, usb_remove_store);
583 
584 
585 static struct attribute *dev_attrs[] = {
586 	/* current configuration's attributes */
587 	&dev_attr_configuration.attr,
588 	&dev_attr_bNumInterfaces.attr,
589 	&dev_attr_bConfigurationValue.attr,
590 	&dev_attr_bmAttributes.attr,
591 	&dev_attr_bMaxPower.attr,
592 	/* device attributes */
593 	&dev_attr_urbnum.attr,
594 	&dev_attr_idVendor.attr,
595 	&dev_attr_idProduct.attr,
596 	&dev_attr_bcdDevice.attr,
597 	&dev_attr_bDeviceClass.attr,
598 	&dev_attr_bDeviceSubClass.attr,
599 	&dev_attr_bDeviceProtocol.attr,
600 	&dev_attr_bNumConfigurations.attr,
601 	&dev_attr_bMaxPacketSize0.attr,
602 	&dev_attr_speed.attr,
603 	&dev_attr_busnum.attr,
604 	&dev_attr_devnum.attr,
605 	&dev_attr_devpath.attr,
606 	&dev_attr_version.attr,
607 	&dev_attr_maxchild.attr,
608 	&dev_attr_quirks.attr,
609 	&dev_attr_avoid_reset_quirk.attr,
610 	&dev_attr_authorized.attr,
611 	&dev_attr_remove.attr,
612 	NULL,
613 };
614 static struct attribute_group dev_attr_grp = {
615 	.attrs = dev_attrs,
616 };
617 
618 /* When modifying this list, be sure to modify dev_string_attrs_are_visible()
619  * accordingly.
620  */
621 static struct attribute *dev_string_attrs[] = {
622 	&dev_attr_manufacturer.attr,
623 	&dev_attr_product.attr,
624 	&dev_attr_serial.attr,
625 	NULL
626 };
627 
628 static mode_t dev_string_attrs_are_visible(struct kobject *kobj,
629 		struct attribute *a, int n)
630 {
631 	struct device *dev = container_of(kobj, struct device, kobj);
632 	struct usb_device *udev = to_usb_device(dev);
633 
634 	if (a == &dev_attr_manufacturer.attr) {
635 		if (udev->manufacturer == NULL)
636 			return 0;
637 	} else if (a == &dev_attr_product.attr) {
638 		if (udev->product == NULL)
639 			return 0;
640 	} else if (a == &dev_attr_serial.attr) {
641 		if (udev->serial == NULL)
642 			return 0;
643 	}
644 	return a->mode;
645 }
646 
647 static struct attribute_group dev_string_attr_grp = {
648 	.attrs =	dev_string_attrs,
649 	.is_visible =	dev_string_attrs_are_visible,
650 };
651 
652 const struct attribute_group *usb_device_groups[] = {
653 	&dev_attr_grp,
654 	&dev_string_attr_grp,
655 	NULL
656 };
657 
658 /* Binary descriptors */
659 
660 static ssize_t
661 read_descriptors(struct file *filp, struct kobject *kobj,
662 		struct bin_attribute *attr,
663 		char *buf, loff_t off, size_t count)
664 {
665 	struct device *dev = container_of(kobj, struct device, kobj);
666 	struct usb_device *udev = to_usb_device(dev);
667 	size_t nleft = count;
668 	size_t srclen, n;
669 	int cfgno;
670 	void *src;
671 
672 	/* The binary attribute begins with the device descriptor.
673 	 * Following that are the raw descriptor entries for all the
674 	 * configurations (config plus subsidiary descriptors).
675 	 */
676 	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
677 			nleft > 0; ++cfgno) {
678 		if (cfgno < 0) {
679 			src = &udev->descriptor;
680 			srclen = sizeof(struct usb_device_descriptor);
681 		} else {
682 			src = udev->rawdescriptors[cfgno];
683 			srclen = __le16_to_cpu(udev->config[cfgno].desc.
684 					wTotalLength);
685 		}
686 		if (off < srclen) {
687 			n = min(nleft, srclen - (size_t) off);
688 			memcpy(buf, src + off, n);
689 			nleft -= n;
690 			buf += n;
691 			off = 0;
692 		} else {
693 			off -= srclen;
694 		}
695 	}
696 	return count - nleft;
697 }
698 
699 static struct bin_attribute dev_bin_attr_descriptors = {
700 	.attr = {.name = "descriptors", .mode = 0444},
701 	.read = read_descriptors,
702 	.size = 18 + 65535,	/* dev descr + max-size raw descriptor */
703 };
704 
705 int usb_create_sysfs_dev_files(struct usb_device *udev)
706 {
707 	struct device *dev = &udev->dev;
708 	int retval;
709 
710 	retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
711 	if (retval)
712 		goto error;
713 
714 	retval = add_persist_attributes(dev);
715 	if (retval)
716 		goto error;
717 
718 	retval = add_power_attributes(dev);
719 	if (retval)
720 		goto error;
721 	return retval;
722 error:
723 	usb_remove_sysfs_dev_files(udev);
724 	return retval;
725 }
726 
727 void usb_remove_sysfs_dev_files(struct usb_device *udev)
728 {
729 	struct device *dev = &udev->dev;
730 
731 	remove_power_attributes(dev);
732 	remove_persist_attributes(dev);
733 	device_remove_bin_file(dev, &dev_bin_attr_descriptors);
734 }
735 
736 /* Interface Accociation Descriptor fields */
737 #define usb_intf_assoc_attr(field, format_string)			\
738 static ssize_t								\
739 show_iad_##field(struct device *dev, struct device_attribute *attr,	\
740 		char *buf)						\
741 {									\
742 	struct usb_interface *intf = to_usb_interface(dev);		\
743 									\
744 	return sprintf(buf, format_string,				\
745 			intf->intf_assoc->field); 			\
746 }									\
747 static DEVICE_ATTR(iad_##field, S_IRUGO, show_iad_##field, NULL);
748 
749 usb_intf_assoc_attr(bFirstInterface, "%02x\n")
750 usb_intf_assoc_attr(bInterfaceCount, "%02d\n")
751 usb_intf_assoc_attr(bFunctionClass, "%02x\n")
752 usb_intf_assoc_attr(bFunctionSubClass, "%02x\n")
753 usb_intf_assoc_attr(bFunctionProtocol, "%02x\n")
754 
755 /* Interface fields */
756 #define usb_intf_attr(field, format_string)				\
757 static ssize_t								\
758 show_##field(struct device *dev, struct device_attribute *attr,	\
759 		char *buf)						\
760 {									\
761 	struct usb_interface *intf = to_usb_interface(dev);		\
762 									\
763 	return sprintf(buf, format_string,				\
764 			intf->cur_altsetting->desc.field); 		\
765 }									\
766 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
767 
768 usb_intf_attr(bInterfaceNumber, "%02x\n")
769 usb_intf_attr(bAlternateSetting, "%2d\n")
770 usb_intf_attr(bNumEndpoints, "%02x\n")
771 usb_intf_attr(bInterfaceClass, "%02x\n")
772 usb_intf_attr(bInterfaceSubClass, "%02x\n")
773 usb_intf_attr(bInterfaceProtocol, "%02x\n")
774 
775 static ssize_t show_interface_string(struct device *dev,
776 		struct device_attribute *attr, char *buf)
777 {
778 	struct usb_interface *intf;
779 	char *string;
780 
781 	intf = to_usb_interface(dev);
782 	string = intf->cur_altsetting->string;
783 	barrier();		/* The altsetting might change! */
784 
785 	if (!string)
786 		return 0;
787 	return sprintf(buf, "%s\n", string);
788 }
789 static DEVICE_ATTR(interface, S_IRUGO, show_interface_string, NULL);
790 
791 static ssize_t show_modalias(struct device *dev,
792 		struct device_attribute *attr, char *buf)
793 {
794 	struct usb_interface *intf;
795 	struct usb_device *udev;
796 	struct usb_host_interface *alt;
797 
798 	intf = to_usb_interface(dev);
799 	udev = interface_to_usbdev(intf);
800 	alt = intf->cur_altsetting;
801 
802 	return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
803 			"ic%02Xisc%02Xip%02X\n",
804 			le16_to_cpu(udev->descriptor.idVendor),
805 			le16_to_cpu(udev->descriptor.idProduct),
806 			le16_to_cpu(udev->descriptor.bcdDevice),
807 			udev->descriptor.bDeviceClass,
808 			udev->descriptor.bDeviceSubClass,
809 			udev->descriptor.bDeviceProtocol,
810 			alt->desc.bInterfaceClass,
811 			alt->desc.bInterfaceSubClass,
812 			alt->desc.bInterfaceProtocol);
813 }
814 static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);
815 
816 static ssize_t show_supports_autosuspend(struct device *dev,
817 		struct device_attribute *attr, char *buf)
818 {
819 	struct usb_interface *intf;
820 	struct usb_device *udev;
821 	int ret;
822 
823 	intf = to_usb_interface(dev);
824 	udev = interface_to_usbdev(intf);
825 
826 	usb_lock_device(udev);
827 	/* Devices will be autosuspended even when an interface isn't claimed */
828 	if (!intf->dev.driver ||
829 			to_usb_driver(intf->dev.driver)->supports_autosuspend)
830 		ret = sprintf(buf, "%u\n", 1);
831 	else
832 		ret = sprintf(buf, "%u\n", 0);
833 	usb_unlock_device(udev);
834 
835 	return ret;
836 }
837 static DEVICE_ATTR(supports_autosuspend, S_IRUGO, show_supports_autosuspend, NULL);
838 
839 static struct attribute *intf_attrs[] = {
840 	&dev_attr_bInterfaceNumber.attr,
841 	&dev_attr_bAlternateSetting.attr,
842 	&dev_attr_bNumEndpoints.attr,
843 	&dev_attr_bInterfaceClass.attr,
844 	&dev_attr_bInterfaceSubClass.attr,
845 	&dev_attr_bInterfaceProtocol.attr,
846 	&dev_attr_modalias.attr,
847 	&dev_attr_supports_autosuspend.attr,
848 	NULL,
849 };
850 static struct attribute_group intf_attr_grp = {
851 	.attrs = intf_attrs,
852 };
853 
854 static struct attribute *intf_assoc_attrs[] = {
855 	&dev_attr_iad_bFirstInterface.attr,
856 	&dev_attr_iad_bInterfaceCount.attr,
857 	&dev_attr_iad_bFunctionClass.attr,
858 	&dev_attr_iad_bFunctionSubClass.attr,
859 	&dev_attr_iad_bFunctionProtocol.attr,
860 	NULL,
861 };
862 
863 static mode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
864 		struct attribute *a, int n)
865 {
866 	struct device *dev = container_of(kobj, struct device, kobj);
867 	struct usb_interface *intf = to_usb_interface(dev);
868 
869 	if (intf->intf_assoc == NULL)
870 		return 0;
871 	return a->mode;
872 }
873 
874 static struct attribute_group intf_assoc_attr_grp = {
875 	.attrs =	intf_assoc_attrs,
876 	.is_visible =	intf_assoc_attrs_are_visible,
877 };
878 
879 const struct attribute_group *usb_interface_groups[] = {
880 	&intf_attr_grp,
881 	&intf_assoc_attr_grp,
882 	NULL
883 };
884 
885 int usb_create_sysfs_intf_files(struct usb_interface *intf)
886 {
887 	struct usb_device *udev = interface_to_usbdev(intf);
888 	struct usb_host_interface *alt = intf->cur_altsetting;
889 	int retval;
890 
891 	if (intf->sysfs_files_created || intf->unregistering)
892 		return 0;
893 
894 	if (alt->string == NULL &&
895 			!(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
896 		alt->string = usb_cache_string(udev, alt->desc.iInterface);
897 	if (alt->string)
898 		retval = device_create_file(&intf->dev, &dev_attr_interface);
899 	intf->sysfs_files_created = 1;
900 	return 0;
901 }
902 
903 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
904 {
905 	if (!intf->sysfs_files_created)
906 		return;
907 
908 	device_remove_file(&intf->dev, &dev_attr_interface);
909 	intf->sysfs_files_created = 0;
910 }
911