xref: /openbmc/linux/drivers/usb/core/sysfs.c (revision a09d2831)
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 	default:
119 		speed = "unknown";
120 	}
121 	return sprintf(buf, "%s\n", speed);
122 }
123 static DEVICE_ATTR(speed, S_IRUGO, show_speed, NULL);
124 
125 static ssize_t
126 show_busnum(struct device *dev, struct device_attribute *attr, char *buf)
127 {
128 	struct usb_device *udev;
129 
130 	udev = to_usb_device(dev);
131 	return sprintf(buf, "%d\n", udev->bus->busnum);
132 }
133 static DEVICE_ATTR(busnum, S_IRUGO, show_busnum, NULL);
134 
135 static ssize_t
136 show_devnum(struct device *dev, struct device_attribute *attr, char *buf)
137 {
138 	struct usb_device *udev;
139 
140 	udev = to_usb_device(dev);
141 	return sprintf(buf, "%d\n", udev->devnum);
142 }
143 static DEVICE_ATTR(devnum, S_IRUGO, show_devnum, NULL);
144 
145 static ssize_t
146 show_devpath(struct device *dev, struct device_attribute *attr, char *buf)
147 {
148 	struct usb_device *udev;
149 
150 	udev = to_usb_device(dev);
151 	return sprintf(buf, "%s\n", udev->devpath);
152 }
153 static DEVICE_ATTR(devpath, S_IRUGO, show_devpath, NULL);
154 
155 static ssize_t
156 show_version(struct device *dev, struct device_attribute *attr, char *buf)
157 {
158 	struct usb_device *udev;
159 	u16 bcdUSB;
160 
161 	udev = to_usb_device(dev);
162 	bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
163 	return sprintf(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
164 }
165 static DEVICE_ATTR(version, S_IRUGO, show_version, NULL);
166 
167 static ssize_t
168 show_maxchild(struct device *dev, struct device_attribute *attr, char *buf)
169 {
170 	struct usb_device *udev;
171 
172 	udev = to_usb_device(dev);
173 	return sprintf(buf, "%d\n", udev->maxchild);
174 }
175 static DEVICE_ATTR(maxchild, S_IRUGO, show_maxchild, NULL);
176 
177 static ssize_t
178 show_quirks(struct device *dev, struct device_attribute *attr, char *buf)
179 {
180 	struct usb_device *udev;
181 
182 	udev = to_usb_device(dev);
183 	return sprintf(buf, "0x%x\n", udev->quirks);
184 }
185 static DEVICE_ATTR(quirks, S_IRUGO, show_quirks, NULL);
186 
187 static ssize_t
188 show_urbnum(struct device *dev, struct device_attribute *attr, char *buf)
189 {
190 	struct usb_device *udev;
191 
192 	udev = to_usb_device(dev);
193 	return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
194 }
195 static DEVICE_ATTR(urbnum, S_IRUGO, show_urbnum, NULL);
196 
197 
198 #ifdef	CONFIG_PM
199 
200 static const char power_group[] = "power";
201 
202 static ssize_t
203 show_persist(struct device *dev, struct device_attribute *attr, char *buf)
204 {
205 	struct usb_device *udev = to_usb_device(dev);
206 
207 	return sprintf(buf, "%d\n", udev->persist_enabled);
208 }
209 
210 static ssize_t
211 set_persist(struct device *dev, struct device_attribute *attr,
212 		const char *buf, size_t count)
213 {
214 	struct usb_device *udev = to_usb_device(dev);
215 	int value;
216 
217 	/* Hubs are always enabled for USB_PERSIST */
218 	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
219 		return -EPERM;
220 
221 	if (sscanf(buf, "%d", &value) != 1)
222 		return -EINVAL;
223 	usb_pm_lock(udev);
224 	udev->persist_enabled = !!value;
225 	usb_pm_unlock(udev);
226 	return count;
227 }
228 
229 static DEVICE_ATTR(persist, S_IRUGO | S_IWUSR, show_persist, set_persist);
230 
231 static int add_persist_attributes(struct device *dev)
232 {
233 	int rc = 0;
234 
235 	if (is_usb_device(dev)) {
236 		struct usb_device *udev = to_usb_device(dev);
237 
238 		/* Hubs are automatically enabled for USB_PERSIST,
239 		 * no point in creating the attribute file.
240 		 */
241 		if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
242 			rc = sysfs_add_file_to_group(&dev->kobj,
243 					&dev_attr_persist.attr,
244 					power_group);
245 	}
246 	return rc;
247 }
248 
249 static void remove_persist_attributes(struct device *dev)
250 {
251 	sysfs_remove_file_from_group(&dev->kobj,
252 			&dev_attr_persist.attr,
253 			power_group);
254 }
255 #else
256 
257 #define add_persist_attributes(dev)	0
258 #define remove_persist_attributes(dev)	do {} while (0)
259 
260 #endif	/* CONFIG_PM */
261 
262 #ifdef	CONFIG_USB_SUSPEND
263 
264 static ssize_t
265 show_connected_duration(struct device *dev, struct device_attribute *attr,
266 		char *buf)
267 {
268 	struct usb_device *udev = to_usb_device(dev);
269 
270 	return sprintf(buf, "%u\n",
271 			jiffies_to_msecs(jiffies - udev->connect_time));
272 }
273 
274 static DEVICE_ATTR(connected_duration, S_IRUGO, show_connected_duration, NULL);
275 
276 /*
277  * If the device is resumed, the last time the device was suspended has
278  * been pre-subtracted from active_duration.  We add the current time to
279  * get the duration that the device was actually active.
280  *
281  * If the device is suspended, the active_duration is up-to-date.
282  */
283 static ssize_t
284 show_active_duration(struct device *dev, struct device_attribute *attr,
285 		char *buf)
286 {
287 	struct usb_device *udev = to_usb_device(dev);
288 	int duration;
289 
290 	if (udev->state != USB_STATE_SUSPENDED)
291 		duration = jiffies_to_msecs(jiffies + udev->active_duration);
292 	else
293 		duration = jiffies_to_msecs(udev->active_duration);
294 	return sprintf(buf, "%u\n", duration);
295 }
296 
297 static DEVICE_ATTR(active_duration, S_IRUGO, show_active_duration, NULL);
298 
299 static ssize_t
300 show_autosuspend(struct device *dev, struct device_attribute *attr, char *buf)
301 {
302 	struct usb_device *udev = to_usb_device(dev);
303 
304 	return sprintf(buf, "%d\n", udev->autosuspend_delay / HZ);
305 }
306 
307 static ssize_t
308 set_autosuspend(struct device *dev, struct device_attribute *attr,
309 		const char *buf, size_t count)
310 {
311 	struct usb_device *udev = to_usb_device(dev);
312 	int value;
313 
314 	if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/HZ ||
315 			value <= - INT_MAX/HZ)
316 		return -EINVAL;
317 	value *= HZ;
318 
319 	udev->autosuspend_delay = value;
320 	if (value >= 0)
321 		usb_try_autosuspend_device(udev);
322 	else {
323 		if (usb_autoresume_device(udev) == 0)
324 			usb_autosuspend_device(udev);
325 	}
326 	return count;
327 }
328 
329 static DEVICE_ATTR(autosuspend, S_IRUGO | S_IWUSR,
330 		show_autosuspend, set_autosuspend);
331 
332 static const char on_string[] = "on";
333 static const char auto_string[] = "auto";
334 
335 static ssize_t
336 show_level(struct device *dev, struct device_attribute *attr, char *buf)
337 {
338 	struct usb_device *udev = to_usb_device(dev);
339 	const char *p = auto_string;
340 
341 	if (udev->state != USB_STATE_SUSPENDED && udev->autosuspend_disabled)
342 		p = on_string;
343 	return sprintf(buf, "%s\n", p);
344 }
345 
346 static ssize_t
347 set_level(struct device *dev, struct device_attribute *attr,
348 		const char *buf, size_t count)
349 {
350 	struct usb_device *udev = to_usb_device(dev);
351 	int len = count;
352 	char *cp;
353 	int rc = 0;
354 	int old_autosuspend_disabled;
355 
356 	cp = memchr(buf, '\n', count);
357 	if (cp)
358 		len = cp - buf;
359 
360 	usb_lock_device(udev);
361 	old_autosuspend_disabled = udev->autosuspend_disabled;
362 
363 	/* Setting the flags without calling usb_pm_lock is a subject to
364 	 * races, but who cares...
365 	 */
366 	if (len == sizeof on_string - 1 &&
367 			strncmp(buf, on_string, len) == 0) {
368 		udev->autosuspend_disabled = 1;
369 		rc = usb_external_resume_device(udev, PMSG_USER_RESUME);
370 
371 	} else if (len == sizeof auto_string - 1 &&
372 			strncmp(buf, auto_string, len) == 0) {
373 		udev->autosuspend_disabled = 0;
374 		rc = usb_external_resume_device(udev, PMSG_USER_RESUME);
375 
376 	} else
377 		rc = -EINVAL;
378 
379 	if (rc)
380 		udev->autosuspend_disabled = old_autosuspend_disabled;
381 	usb_unlock_device(udev);
382 	return (rc < 0 ? rc : count);
383 }
384 
385 static DEVICE_ATTR(level, S_IRUGO | S_IWUSR, show_level, set_level);
386 
387 static int add_power_attributes(struct device *dev)
388 {
389 	int rc = 0;
390 
391 	if (is_usb_device(dev)) {
392 		rc = sysfs_add_file_to_group(&dev->kobj,
393 				&dev_attr_autosuspend.attr,
394 				power_group);
395 		if (rc == 0)
396 			rc = sysfs_add_file_to_group(&dev->kobj,
397 					&dev_attr_level.attr,
398 					power_group);
399 		if (rc == 0)
400 			rc = sysfs_add_file_to_group(&dev->kobj,
401 					&dev_attr_connected_duration.attr,
402 					power_group);
403 		if (rc == 0)
404 			rc = sysfs_add_file_to_group(&dev->kobj,
405 					&dev_attr_active_duration.attr,
406 					power_group);
407 	}
408 	return rc;
409 }
410 
411 static void remove_power_attributes(struct device *dev)
412 {
413 	sysfs_remove_file_from_group(&dev->kobj,
414 			&dev_attr_active_duration.attr,
415 			power_group);
416 	sysfs_remove_file_from_group(&dev->kobj,
417 			&dev_attr_connected_duration.attr,
418 			power_group);
419 	sysfs_remove_file_from_group(&dev->kobj,
420 			&dev_attr_level.attr,
421 			power_group);
422 	sysfs_remove_file_from_group(&dev->kobj,
423 			&dev_attr_autosuspend.attr,
424 			power_group);
425 }
426 
427 #else
428 
429 #define add_power_attributes(dev)	0
430 #define remove_power_attributes(dev)	do {} while (0)
431 
432 #endif	/* CONFIG_USB_SUSPEND */
433 
434 
435 /* Descriptor fields */
436 #define usb_descriptor_attr_le16(field, format_string)			\
437 static ssize_t								\
438 show_##field(struct device *dev, struct device_attribute *attr,	\
439 		char *buf)						\
440 {									\
441 	struct usb_device *udev;					\
442 									\
443 	udev = to_usb_device(dev);					\
444 	return sprintf(buf, format_string, 				\
445 			le16_to_cpu(udev->descriptor.field));		\
446 }									\
447 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
448 
449 usb_descriptor_attr_le16(idVendor, "%04x\n")
450 usb_descriptor_attr_le16(idProduct, "%04x\n")
451 usb_descriptor_attr_le16(bcdDevice, "%04x\n")
452 
453 #define usb_descriptor_attr(field, format_string)			\
454 static ssize_t								\
455 show_##field(struct device *dev, struct device_attribute *attr,	\
456 		char *buf)						\
457 {									\
458 	struct usb_device *udev;					\
459 									\
460 	udev = to_usb_device(dev);					\
461 	return sprintf(buf, format_string, udev->descriptor.field);	\
462 }									\
463 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
464 
465 usb_descriptor_attr(bDeviceClass, "%02x\n")
466 usb_descriptor_attr(bDeviceSubClass, "%02x\n")
467 usb_descriptor_attr(bDeviceProtocol, "%02x\n")
468 usb_descriptor_attr(bNumConfigurations, "%d\n")
469 usb_descriptor_attr(bMaxPacketSize0, "%d\n")
470 
471 
472 
473 /* show if the device is authorized (1) or not (0) */
474 static ssize_t usb_dev_authorized_show(struct device *dev,
475 				       struct device_attribute *attr,
476 				       char *buf)
477 {
478 	struct usb_device *usb_dev = to_usb_device(dev);
479 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
480 }
481 
482 
483 /*
484  * Authorize a device to be used in the system
485  *
486  * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
487  */
488 static ssize_t usb_dev_authorized_store(struct device *dev,
489 					struct device_attribute *attr,
490 					const char *buf, size_t size)
491 {
492 	ssize_t result;
493 	struct usb_device *usb_dev = to_usb_device(dev);
494 	unsigned val;
495 	result = sscanf(buf, "%u\n", &val);
496 	if (result != 1)
497 		result = -EINVAL;
498 	else if (val == 0)
499 		result = usb_deauthorize_device(usb_dev);
500 	else
501 		result = usb_authorize_device(usb_dev);
502 	return result < 0? result : size;
503 }
504 
505 static DEVICE_ATTR(authorized, 0644,
506 	    usb_dev_authorized_show, usb_dev_authorized_store);
507 
508 /* "Safely remove a device" */
509 static ssize_t usb_remove_store(struct device *dev,
510 		struct device_attribute *attr,
511 		const char *buf, size_t count)
512 {
513 	struct usb_device *udev = to_usb_device(dev);
514 	int rc = 0;
515 
516 	usb_lock_device(udev);
517 	if (udev->state != USB_STATE_NOTATTACHED) {
518 
519 		/* To avoid races, first unconfigure and then remove */
520 		usb_set_configuration(udev, -1);
521 		rc = usb_remove_device(udev);
522 	}
523 	if (rc == 0)
524 		rc = count;
525 	usb_unlock_device(udev);
526 	return rc;
527 }
528 static DEVICE_ATTR(remove, 0200, NULL, usb_remove_store);
529 
530 
531 static struct attribute *dev_attrs[] = {
532 	/* current configuration's attributes */
533 	&dev_attr_configuration.attr,
534 	&dev_attr_bNumInterfaces.attr,
535 	&dev_attr_bConfigurationValue.attr,
536 	&dev_attr_bmAttributes.attr,
537 	&dev_attr_bMaxPower.attr,
538 	/* device attributes */
539 	&dev_attr_urbnum.attr,
540 	&dev_attr_idVendor.attr,
541 	&dev_attr_idProduct.attr,
542 	&dev_attr_bcdDevice.attr,
543 	&dev_attr_bDeviceClass.attr,
544 	&dev_attr_bDeviceSubClass.attr,
545 	&dev_attr_bDeviceProtocol.attr,
546 	&dev_attr_bNumConfigurations.attr,
547 	&dev_attr_bMaxPacketSize0.attr,
548 	&dev_attr_speed.attr,
549 	&dev_attr_busnum.attr,
550 	&dev_attr_devnum.attr,
551 	&dev_attr_devpath.attr,
552 	&dev_attr_version.attr,
553 	&dev_attr_maxchild.attr,
554 	&dev_attr_quirks.attr,
555 	&dev_attr_authorized.attr,
556 	&dev_attr_remove.attr,
557 	NULL,
558 };
559 static struct attribute_group dev_attr_grp = {
560 	.attrs = dev_attrs,
561 };
562 
563 /* When modifying this list, be sure to modify dev_string_attrs_are_visible()
564  * accordingly.
565  */
566 static struct attribute *dev_string_attrs[] = {
567 	&dev_attr_manufacturer.attr,
568 	&dev_attr_product.attr,
569 	&dev_attr_serial.attr,
570 	NULL
571 };
572 
573 static mode_t dev_string_attrs_are_visible(struct kobject *kobj,
574 		struct attribute *a, int n)
575 {
576 	struct device *dev = container_of(kobj, struct device, kobj);
577 	struct usb_device *udev = to_usb_device(dev);
578 
579 	if (a == &dev_attr_manufacturer.attr) {
580 		if (udev->manufacturer == NULL)
581 			return 0;
582 	} else if (a == &dev_attr_product.attr) {
583 		if (udev->product == NULL)
584 			return 0;
585 	} else if (a == &dev_attr_serial.attr) {
586 		if (udev->serial == NULL)
587 			return 0;
588 	}
589 	return a->mode;
590 }
591 
592 static struct attribute_group dev_string_attr_grp = {
593 	.attrs =	dev_string_attrs,
594 	.is_visible =	dev_string_attrs_are_visible,
595 };
596 
597 const struct attribute_group *usb_device_groups[] = {
598 	&dev_attr_grp,
599 	&dev_string_attr_grp,
600 	NULL
601 };
602 
603 /* Binary descriptors */
604 
605 static ssize_t
606 read_descriptors(struct kobject *kobj, struct bin_attribute *attr,
607 		char *buf, loff_t off, size_t count)
608 {
609 	struct device *dev = container_of(kobj, struct device, kobj);
610 	struct usb_device *udev = to_usb_device(dev);
611 	size_t nleft = count;
612 	size_t srclen, n;
613 	int cfgno;
614 	void *src;
615 
616 	/* The binary attribute begins with the device descriptor.
617 	 * Following that are the raw descriptor entries for all the
618 	 * configurations (config plus subsidiary descriptors).
619 	 */
620 	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
621 			nleft > 0; ++cfgno) {
622 		if (cfgno < 0) {
623 			src = &udev->descriptor;
624 			srclen = sizeof(struct usb_device_descriptor);
625 		} else {
626 			src = udev->rawdescriptors[cfgno];
627 			srclen = __le16_to_cpu(udev->config[cfgno].desc.
628 					wTotalLength);
629 		}
630 		if (off < srclen) {
631 			n = min(nleft, srclen - (size_t) off);
632 			memcpy(buf, src + off, n);
633 			nleft -= n;
634 			buf += n;
635 			off = 0;
636 		} else {
637 			off -= srclen;
638 		}
639 	}
640 	return count - nleft;
641 }
642 
643 static struct bin_attribute dev_bin_attr_descriptors = {
644 	.attr = {.name = "descriptors", .mode = 0444},
645 	.read = read_descriptors,
646 	.size = 18 + 65535,	/* dev descr + max-size raw descriptor */
647 };
648 
649 int usb_create_sysfs_dev_files(struct usb_device *udev)
650 {
651 	struct device *dev = &udev->dev;
652 	int retval;
653 
654 	retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
655 	if (retval)
656 		goto error;
657 
658 	retval = add_persist_attributes(dev);
659 	if (retval)
660 		goto error;
661 
662 	retval = add_power_attributes(dev);
663 	if (retval)
664 		goto error;
665 	return retval;
666 error:
667 	usb_remove_sysfs_dev_files(udev);
668 	return retval;
669 }
670 
671 void usb_remove_sysfs_dev_files(struct usb_device *udev)
672 {
673 	struct device *dev = &udev->dev;
674 
675 	remove_power_attributes(dev);
676 	remove_persist_attributes(dev);
677 	device_remove_bin_file(dev, &dev_bin_attr_descriptors);
678 }
679 
680 /* Interface Accociation Descriptor fields */
681 #define usb_intf_assoc_attr(field, format_string)			\
682 static ssize_t								\
683 show_iad_##field(struct device *dev, struct device_attribute *attr,	\
684 		char *buf)						\
685 {									\
686 	struct usb_interface *intf = to_usb_interface(dev);		\
687 									\
688 	return sprintf(buf, format_string,				\
689 			intf->intf_assoc->field); 			\
690 }									\
691 static DEVICE_ATTR(iad_##field, S_IRUGO, show_iad_##field, NULL);
692 
693 usb_intf_assoc_attr(bFirstInterface, "%02x\n")
694 usb_intf_assoc_attr(bInterfaceCount, "%02d\n")
695 usb_intf_assoc_attr(bFunctionClass, "%02x\n")
696 usb_intf_assoc_attr(bFunctionSubClass, "%02x\n")
697 usb_intf_assoc_attr(bFunctionProtocol, "%02x\n")
698 
699 /* Interface fields */
700 #define usb_intf_attr(field, format_string)				\
701 static ssize_t								\
702 show_##field(struct device *dev, struct device_attribute *attr,	\
703 		char *buf)						\
704 {									\
705 	struct usb_interface *intf = to_usb_interface(dev);		\
706 									\
707 	return sprintf(buf, format_string,				\
708 			intf->cur_altsetting->desc.field); 		\
709 }									\
710 static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
711 
712 usb_intf_attr(bInterfaceNumber, "%02x\n")
713 usb_intf_attr(bAlternateSetting, "%2d\n")
714 usb_intf_attr(bNumEndpoints, "%02x\n")
715 usb_intf_attr(bInterfaceClass, "%02x\n")
716 usb_intf_attr(bInterfaceSubClass, "%02x\n")
717 usb_intf_attr(bInterfaceProtocol, "%02x\n")
718 
719 static ssize_t show_interface_string(struct device *dev,
720 		struct device_attribute *attr, char *buf)
721 {
722 	struct usb_interface *intf;
723 	char *string;
724 
725 	intf = to_usb_interface(dev);
726 	string = intf->cur_altsetting->string;
727 	barrier();		/* The altsetting might change! */
728 
729 	if (!string)
730 		return 0;
731 	return sprintf(buf, "%s\n", string);
732 }
733 static DEVICE_ATTR(interface, S_IRUGO, show_interface_string, NULL);
734 
735 static ssize_t show_modalias(struct device *dev,
736 		struct device_attribute *attr, char *buf)
737 {
738 	struct usb_interface *intf;
739 	struct usb_device *udev;
740 	struct usb_host_interface *alt;
741 
742 	intf = to_usb_interface(dev);
743 	udev = interface_to_usbdev(intf);
744 	alt = intf->cur_altsetting;
745 
746 	return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
747 			"ic%02Xisc%02Xip%02X\n",
748 			le16_to_cpu(udev->descriptor.idVendor),
749 			le16_to_cpu(udev->descriptor.idProduct),
750 			le16_to_cpu(udev->descriptor.bcdDevice),
751 			udev->descriptor.bDeviceClass,
752 			udev->descriptor.bDeviceSubClass,
753 			udev->descriptor.bDeviceProtocol,
754 			alt->desc.bInterfaceClass,
755 			alt->desc.bInterfaceSubClass,
756 			alt->desc.bInterfaceProtocol);
757 }
758 static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL);
759 
760 static ssize_t show_supports_autosuspend(struct device *dev,
761 		struct device_attribute *attr, char *buf)
762 {
763 	struct usb_interface *intf;
764 	struct usb_device *udev;
765 	int ret;
766 
767 	intf = to_usb_interface(dev);
768 	udev = interface_to_usbdev(intf);
769 
770 	usb_lock_device(udev);
771 	/* Devices will be autosuspended even when an interface isn't claimed */
772 	if (!intf->dev.driver ||
773 			to_usb_driver(intf->dev.driver)->supports_autosuspend)
774 		ret = sprintf(buf, "%u\n", 1);
775 	else
776 		ret = sprintf(buf, "%u\n", 0);
777 	usb_unlock_device(udev);
778 
779 	return ret;
780 }
781 static DEVICE_ATTR(supports_autosuspend, S_IRUGO, show_supports_autosuspend, NULL);
782 
783 static struct attribute *intf_attrs[] = {
784 	&dev_attr_bInterfaceNumber.attr,
785 	&dev_attr_bAlternateSetting.attr,
786 	&dev_attr_bNumEndpoints.attr,
787 	&dev_attr_bInterfaceClass.attr,
788 	&dev_attr_bInterfaceSubClass.attr,
789 	&dev_attr_bInterfaceProtocol.attr,
790 	&dev_attr_modalias.attr,
791 	&dev_attr_supports_autosuspend.attr,
792 	NULL,
793 };
794 static struct attribute_group intf_attr_grp = {
795 	.attrs = intf_attrs,
796 };
797 
798 static struct attribute *intf_assoc_attrs[] = {
799 	&dev_attr_iad_bFirstInterface.attr,
800 	&dev_attr_iad_bInterfaceCount.attr,
801 	&dev_attr_iad_bFunctionClass.attr,
802 	&dev_attr_iad_bFunctionSubClass.attr,
803 	&dev_attr_iad_bFunctionProtocol.attr,
804 	NULL,
805 };
806 
807 static mode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
808 		struct attribute *a, int n)
809 {
810 	struct device *dev = container_of(kobj, struct device, kobj);
811 	struct usb_interface *intf = to_usb_interface(dev);
812 
813 	if (intf->intf_assoc == NULL)
814 		return 0;
815 	return a->mode;
816 }
817 
818 static struct attribute_group intf_assoc_attr_grp = {
819 	.attrs =	intf_assoc_attrs,
820 	.is_visible =	intf_assoc_attrs_are_visible,
821 };
822 
823 const struct attribute_group *usb_interface_groups[] = {
824 	&intf_attr_grp,
825 	&intf_assoc_attr_grp,
826 	NULL
827 };
828 
829 int usb_create_sysfs_intf_files(struct usb_interface *intf)
830 {
831 	struct usb_device *udev = interface_to_usbdev(intf);
832 	struct usb_host_interface *alt = intf->cur_altsetting;
833 	int retval;
834 
835 	if (intf->sysfs_files_created || intf->unregistering)
836 		return 0;
837 
838 	if (alt->string == NULL &&
839 			!(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
840 		alt->string = usb_cache_string(udev, alt->desc.iInterface);
841 	if (alt->string)
842 		retval = device_create_file(&intf->dev, &dev_attr_interface);
843 	intf->sysfs_files_created = 1;
844 	return 0;
845 }
846 
847 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
848 {
849 	if (!intf->sysfs_files_created)
850 		return;
851 
852 	device_remove_file(&intf->dev, &dev_attr_interface);
853 	intf->sysfs_files_created = 0;
854 }
855