xref: /openbmc/linux/drivers/usb/core/sysfs.c (revision 1e8fc4ff)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * drivers/usb/core/sysfs.c
4  *
5  * (C) Copyright 2002 David Brownell
6  * (C) Copyright 2002,2004 Greg Kroah-Hartman
7  * (C) Copyright 2002,2004 IBM Corp.
8  *
9  * All of the sysfs file attributes for usb devices and interfaces.
10  *
11  * Released under the GPLv2 only.
12  */
13 
14 
15 #include <linux/kernel.h>
16 #include <linux/kstrtox.h>
17 #include <linux/string.h>
18 #include <linux/usb.h>
19 #include <linux/usb/hcd.h>
20 #include <linux/usb/quirks.h>
21 #include <linux/of.h>
22 #include "usb.h"
23 
24 /* Active configuration fields */
25 #define usb_actconfig_show(field, format_string)			\
26 static ssize_t field##_show(struct device *dev,				\
27 			    struct device_attribute *attr, char *buf)	\
28 {									\
29 	struct usb_device *udev;					\
30 	struct usb_host_config *actconfig;				\
31 	ssize_t rc;							\
32 									\
33 	udev = to_usb_device(dev);					\
34 	rc = usb_lock_device_interruptible(udev);			\
35 	if (rc < 0)							\
36 		return -EINTR;						\
37 	actconfig = udev->actconfig;					\
38 	if (actconfig)							\
39 		rc = sysfs_emit(buf, format_string,			\
40 				actconfig->desc.field);			\
41 	usb_unlock_device(udev);					\
42 	return rc;							\
43 }									\
44 
45 #define usb_actconfig_attr(field, format_string)		\
46 	usb_actconfig_show(field, format_string)		\
47 	static DEVICE_ATTR_RO(field)
48 
49 usb_actconfig_attr(bNumInterfaces, "%2d\n");
50 usb_actconfig_attr(bmAttributes, "%2x\n");
51 
52 static ssize_t bMaxPower_show(struct device *dev,
53 		struct device_attribute *attr, char *buf)
54 {
55 	struct usb_device *udev;
56 	struct usb_host_config *actconfig;
57 	ssize_t rc;
58 
59 	udev = to_usb_device(dev);
60 	rc = usb_lock_device_interruptible(udev);
61 	if (rc < 0)
62 		return -EINTR;
63 	actconfig = udev->actconfig;
64 	if (actconfig)
65 		rc = sysfs_emit(buf, "%dmA\n", usb_get_max_power(udev, actconfig));
66 	usb_unlock_device(udev);
67 	return rc;
68 }
69 static DEVICE_ATTR_RO(bMaxPower);
70 
71 static ssize_t configuration_show(struct device *dev,
72 		struct device_attribute *attr, char *buf)
73 {
74 	struct usb_device *udev;
75 	struct usb_host_config *actconfig;
76 	ssize_t rc;
77 
78 	udev = to_usb_device(dev);
79 	rc = usb_lock_device_interruptible(udev);
80 	if (rc < 0)
81 		return -EINTR;
82 	actconfig = udev->actconfig;
83 	if (actconfig && actconfig->string)
84 		rc = sysfs_emit(buf, "%s\n", actconfig->string);
85 	usb_unlock_device(udev);
86 	return rc;
87 }
88 static DEVICE_ATTR_RO(configuration);
89 
90 /* configuration value is always present, and r/w */
91 usb_actconfig_show(bConfigurationValue, "%u\n");
92 
93 static ssize_t bConfigurationValue_store(struct device *dev,
94 					 struct device_attribute *attr,
95 					 const char *buf, size_t count)
96 {
97 	struct usb_device	*udev = to_usb_device(dev);
98 	int			config, value, rc;
99 
100 	if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
101 		return -EINVAL;
102 	rc = usb_lock_device_interruptible(udev);
103 	if (rc < 0)
104 		return -EINTR;
105 	value = usb_set_configuration(udev, config);
106 	usb_unlock_device(udev);
107 	return (value < 0) ? value : count;
108 }
109 static DEVICE_ATTR_IGNORE_LOCKDEP(bConfigurationValue, S_IRUGO | S_IWUSR,
110 		bConfigurationValue_show, bConfigurationValue_store);
111 
112 #ifdef CONFIG_OF
113 static ssize_t devspec_show(struct device *dev, struct device_attribute *attr,
114 			    char *buf)
115 {
116 	struct device_node *of_node = dev->of_node;
117 
118 	return sysfs_emit(buf, "%pOF\n", of_node);
119 }
120 static DEVICE_ATTR_RO(devspec);
121 #endif
122 
123 /* String fields */
124 #define usb_string_attr(name)						\
125 static ssize_t  name##_show(struct device *dev,				\
126 		struct device_attribute *attr, char *buf)		\
127 {									\
128 	struct usb_device *udev;					\
129 	int retval;							\
130 									\
131 	udev = to_usb_device(dev);					\
132 	retval = usb_lock_device_interruptible(udev);			\
133 	if (retval < 0)							\
134 		return -EINTR;						\
135 	retval = sysfs_emit(buf, "%s\n", udev->name);			\
136 	usb_unlock_device(udev);					\
137 	return retval;							\
138 }									\
139 static DEVICE_ATTR_RO(name)
140 
141 usb_string_attr(product);
142 usb_string_attr(manufacturer);
143 usb_string_attr(serial);
144 
145 static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
146 			  char *buf)
147 {
148 	struct usb_device *udev;
149 	char *speed;
150 
151 	udev = to_usb_device(dev);
152 
153 	switch (udev->speed) {
154 	case USB_SPEED_LOW:
155 		speed = "1.5";
156 		break;
157 	case USB_SPEED_UNKNOWN:
158 	case USB_SPEED_FULL:
159 		speed = "12";
160 		break;
161 	case USB_SPEED_HIGH:
162 		speed = "480";
163 		break;
164 	case USB_SPEED_SUPER:
165 		speed = "5000";
166 		break;
167 	case USB_SPEED_SUPER_PLUS:
168 		if (udev->ssp_rate == USB_SSP_GEN_2x2)
169 			speed = "20000";
170 		else
171 			speed = "10000";
172 		break;
173 	default:
174 		speed = "unknown";
175 	}
176 	return sysfs_emit(buf, "%s\n", speed);
177 }
178 static DEVICE_ATTR_RO(speed);
179 
180 static ssize_t rx_lanes_show(struct device *dev, struct device_attribute *attr,
181 			  char *buf)
182 {
183 	struct usb_device *udev;
184 
185 	udev = to_usb_device(dev);
186 	return sysfs_emit(buf, "%d\n", udev->rx_lanes);
187 }
188 static DEVICE_ATTR_RO(rx_lanes);
189 
190 static ssize_t tx_lanes_show(struct device *dev, struct device_attribute *attr,
191 			  char *buf)
192 {
193 	struct usb_device *udev;
194 
195 	udev = to_usb_device(dev);
196 	return sysfs_emit(buf, "%d\n", udev->tx_lanes);
197 }
198 static DEVICE_ATTR_RO(tx_lanes);
199 
200 static ssize_t busnum_show(struct device *dev, struct device_attribute *attr,
201 			   char *buf)
202 {
203 	struct usb_device *udev;
204 
205 	udev = to_usb_device(dev);
206 	return sysfs_emit(buf, "%d\n", udev->bus->busnum);
207 }
208 static DEVICE_ATTR_RO(busnum);
209 
210 static ssize_t devnum_show(struct device *dev, struct device_attribute *attr,
211 			   char *buf)
212 {
213 	struct usb_device *udev;
214 
215 	udev = to_usb_device(dev);
216 	return sysfs_emit(buf, "%d\n", udev->devnum);
217 }
218 static DEVICE_ATTR_RO(devnum);
219 
220 static ssize_t devpath_show(struct device *dev, struct device_attribute *attr,
221 			    char *buf)
222 {
223 	struct usb_device *udev;
224 
225 	udev = to_usb_device(dev);
226 	return sysfs_emit(buf, "%s\n", udev->devpath);
227 }
228 static DEVICE_ATTR_RO(devpath);
229 
230 static ssize_t version_show(struct device *dev, struct device_attribute *attr,
231 			    char *buf)
232 {
233 	struct usb_device *udev;
234 	u16 bcdUSB;
235 
236 	udev = to_usb_device(dev);
237 	bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
238 	return sysfs_emit(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
239 }
240 static DEVICE_ATTR_RO(version);
241 
242 static ssize_t maxchild_show(struct device *dev, struct device_attribute *attr,
243 			     char *buf)
244 {
245 	struct usb_device *udev;
246 
247 	udev = to_usb_device(dev);
248 	return sysfs_emit(buf, "%d\n", udev->maxchild);
249 }
250 static DEVICE_ATTR_RO(maxchild);
251 
252 static ssize_t quirks_show(struct device *dev, struct device_attribute *attr,
253 			   char *buf)
254 {
255 	struct usb_device *udev;
256 
257 	udev = to_usb_device(dev);
258 	return sysfs_emit(buf, "0x%x\n", udev->quirks);
259 }
260 static DEVICE_ATTR_RO(quirks);
261 
262 static ssize_t avoid_reset_quirk_show(struct device *dev,
263 				      struct device_attribute *attr, char *buf)
264 {
265 	struct usb_device *udev;
266 
267 	udev = to_usb_device(dev);
268 	return sysfs_emit(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET));
269 }
270 
271 static ssize_t avoid_reset_quirk_store(struct device *dev,
272 				      struct device_attribute *attr,
273 				      const char *buf, size_t count)
274 {
275 	struct usb_device	*udev = to_usb_device(dev);
276 	int			val, rc;
277 
278 	if (sscanf(buf, "%d", &val) != 1 || val < 0 || val > 1)
279 		return -EINVAL;
280 	rc = usb_lock_device_interruptible(udev);
281 	if (rc < 0)
282 		return -EINTR;
283 	if (val)
284 		udev->quirks |= USB_QUIRK_RESET;
285 	else
286 		udev->quirks &= ~USB_QUIRK_RESET;
287 	usb_unlock_device(udev);
288 	return count;
289 }
290 static DEVICE_ATTR_RW(avoid_reset_quirk);
291 
292 static ssize_t urbnum_show(struct device *dev, struct device_attribute *attr,
293 			   char *buf)
294 {
295 	struct usb_device *udev;
296 
297 	udev = to_usb_device(dev);
298 	return sysfs_emit(buf, "%d\n", atomic_read(&udev->urbnum));
299 }
300 static DEVICE_ATTR_RO(urbnum);
301 
302 static ssize_t ltm_capable_show(struct device *dev,
303 				struct device_attribute *attr, char *buf)
304 {
305 	if (usb_device_supports_ltm(to_usb_device(dev)))
306 		return sysfs_emit(buf, "%s\n", "yes");
307 	return sysfs_emit(buf, "%s\n", "no");
308 }
309 static DEVICE_ATTR_RO(ltm_capable);
310 
311 #ifdef	CONFIG_PM
312 
313 static ssize_t persist_show(struct device *dev, struct device_attribute *attr,
314 			    char *buf)
315 {
316 	struct usb_device *udev = to_usb_device(dev);
317 
318 	return sysfs_emit(buf, "%d\n", udev->persist_enabled);
319 }
320 
321 static ssize_t persist_store(struct device *dev, struct device_attribute *attr,
322 			     const char *buf, size_t count)
323 {
324 	struct usb_device *udev = to_usb_device(dev);
325 	int value, rc;
326 
327 	/* Hubs are always enabled for USB_PERSIST */
328 	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
329 		return -EPERM;
330 
331 	if (sscanf(buf, "%d", &value) != 1)
332 		return -EINVAL;
333 
334 	rc = usb_lock_device_interruptible(udev);
335 	if (rc < 0)
336 		return -EINTR;
337 	udev->persist_enabled = !!value;
338 	usb_unlock_device(udev);
339 	return count;
340 }
341 static DEVICE_ATTR_RW(persist);
342 
343 static int add_persist_attributes(struct device *dev)
344 {
345 	int rc = 0;
346 
347 	if (is_usb_device(dev)) {
348 		struct usb_device *udev = to_usb_device(dev);
349 
350 		/* Hubs are automatically enabled for USB_PERSIST,
351 		 * no point in creating the attribute file.
352 		 */
353 		if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
354 			rc = sysfs_add_file_to_group(&dev->kobj,
355 					&dev_attr_persist.attr,
356 					power_group_name);
357 	}
358 	return rc;
359 }
360 
361 static void remove_persist_attributes(struct device *dev)
362 {
363 	sysfs_remove_file_from_group(&dev->kobj,
364 			&dev_attr_persist.attr,
365 			power_group_name);
366 }
367 
368 static ssize_t connected_duration_show(struct device *dev,
369 				       struct device_attribute *attr, char *buf)
370 {
371 	struct usb_device *udev = to_usb_device(dev);
372 
373 	return sysfs_emit(buf, "%u\n",
374 			jiffies_to_msecs(jiffies - udev->connect_time));
375 }
376 static DEVICE_ATTR_RO(connected_duration);
377 
378 /*
379  * If the device is resumed, the last time the device was suspended has
380  * been pre-subtracted from active_duration.  We add the current time to
381  * get the duration that the device was actually active.
382  *
383  * If the device is suspended, the active_duration is up-to-date.
384  */
385 static ssize_t active_duration_show(struct device *dev,
386 				    struct device_attribute *attr, char *buf)
387 {
388 	struct usb_device *udev = to_usb_device(dev);
389 	int duration;
390 
391 	if (udev->state != USB_STATE_SUSPENDED)
392 		duration = jiffies_to_msecs(jiffies + udev->active_duration);
393 	else
394 		duration = jiffies_to_msecs(udev->active_duration);
395 	return sysfs_emit(buf, "%u\n", duration);
396 }
397 static DEVICE_ATTR_RO(active_duration);
398 
399 static ssize_t autosuspend_show(struct device *dev,
400 				struct device_attribute *attr, char *buf)
401 {
402 	return sysfs_emit(buf, "%d\n", dev->power.autosuspend_delay / 1000);
403 }
404 
405 static ssize_t autosuspend_store(struct device *dev,
406 				 struct device_attribute *attr, const char *buf,
407 				 size_t count)
408 {
409 	int value;
410 
411 	if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/1000 ||
412 			value <= -INT_MAX/1000)
413 		return -EINVAL;
414 
415 	pm_runtime_set_autosuspend_delay(dev, value * 1000);
416 	return count;
417 }
418 static DEVICE_ATTR_RW(autosuspend);
419 
420 static const char on_string[] = "on";
421 static const char auto_string[] = "auto";
422 
423 static void warn_level(void)
424 {
425 	static int level_warned;
426 
427 	if (!level_warned) {
428 		level_warned = 1;
429 		printk(KERN_WARNING "WARNING! power/level is deprecated; "
430 				"use power/control instead\n");
431 	}
432 }
433 
434 static ssize_t level_show(struct device *dev, struct device_attribute *attr,
435 			  char *buf)
436 {
437 	struct usb_device *udev = to_usb_device(dev);
438 	const char *p = auto_string;
439 
440 	warn_level();
441 	if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
442 		p = on_string;
443 	return sysfs_emit(buf, "%s\n", p);
444 }
445 
446 static ssize_t level_store(struct device *dev, struct device_attribute *attr,
447 			   const char *buf, size_t count)
448 {
449 	struct usb_device *udev = to_usb_device(dev);
450 	int len = count;
451 	char *cp;
452 	int rc = count;
453 	int rv;
454 
455 	warn_level();
456 	cp = memchr(buf, '\n', count);
457 	if (cp)
458 		len = cp - buf;
459 
460 	rv = usb_lock_device_interruptible(udev);
461 	if (rv < 0)
462 		return -EINTR;
463 
464 	if (len == sizeof on_string - 1 &&
465 			strncmp(buf, on_string, len) == 0)
466 		usb_disable_autosuspend(udev);
467 
468 	else if (len == sizeof auto_string - 1 &&
469 			strncmp(buf, auto_string, len) == 0)
470 		usb_enable_autosuspend(udev);
471 
472 	else
473 		rc = -EINVAL;
474 
475 	usb_unlock_device(udev);
476 	return rc;
477 }
478 static DEVICE_ATTR_RW(level);
479 
480 static ssize_t usb2_hardware_lpm_show(struct device *dev,
481 				      struct device_attribute *attr, char *buf)
482 {
483 	struct usb_device *udev = to_usb_device(dev);
484 	const char *p;
485 
486 	if (udev->usb2_hw_lpm_allowed == 1)
487 		p = "enabled";
488 	else
489 		p = "disabled";
490 
491 	return sysfs_emit(buf, "%s\n", p);
492 }
493 
494 static ssize_t usb2_hardware_lpm_store(struct device *dev,
495 				       struct device_attribute *attr,
496 				       const char *buf, size_t count)
497 {
498 	struct usb_device *udev = to_usb_device(dev);
499 	bool value;
500 	int ret;
501 
502 	ret = usb_lock_device_interruptible(udev);
503 	if (ret < 0)
504 		return -EINTR;
505 
506 	ret = kstrtobool(buf, &value);
507 
508 	if (!ret) {
509 		udev->usb2_hw_lpm_allowed = value;
510 		if (value)
511 			ret = usb_enable_usb2_hardware_lpm(udev);
512 		else
513 			ret = usb_disable_usb2_hardware_lpm(udev);
514 	}
515 
516 	usb_unlock_device(udev);
517 
518 	if (!ret)
519 		return count;
520 
521 	return ret;
522 }
523 static DEVICE_ATTR_RW(usb2_hardware_lpm);
524 
525 static ssize_t usb2_lpm_l1_timeout_show(struct device *dev,
526 					struct device_attribute *attr,
527 					char *buf)
528 {
529 	struct usb_device *udev = to_usb_device(dev);
530 	return sysfs_emit(buf, "%d\n", udev->l1_params.timeout);
531 }
532 
533 static ssize_t usb2_lpm_l1_timeout_store(struct device *dev,
534 					 struct device_attribute *attr,
535 					 const char *buf, size_t count)
536 {
537 	struct usb_device *udev = to_usb_device(dev);
538 	u16 timeout;
539 
540 	if (kstrtou16(buf, 0, &timeout))
541 		return -EINVAL;
542 
543 	udev->l1_params.timeout = timeout;
544 
545 	return count;
546 }
547 static DEVICE_ATTR_RW(usb2_lpm_l1_timeout);
548 
549 static ssize_t usb2_lpm_besl_show(struct device *dev,
550 				  struct device_attribute *attr, char *buf)
551 {
552 	struct usb_device *udev = to_usb_device(dev);
553 	return sysfs_emit(buf, "%d\n", udev->l1_params.besl);
554 }
555 
556 static ssize_t usb2_lpm_besl_store(struct device *dev,
557 				   struct device_attribute *attr,
558 				   const char *buf, size_t count)
559 {
560 	struct usb_device *udev = to_usb_device(dev);
561 	u8 besl;
562 
563 	if (kstrtou8(buf, 0, &besl) || besl > 15)
564 		return -EINVAL;
565 
566 	udev->l1_params.besl = besl;
567 
568 	return count;
569 }
570 static DEVICE_ATTR_RW(usb2_lpm_besl);
571 
572 static ssize_t usb3_hardware_lpm_u1_show(struct device *dev,
573 				      struct device_attribute *attr, char *buf)
574 {
575 	struct usb_device *udev = to_usb_device(dev);
576 	const char *p;
577 	int rc;
578 
579 	rc = usb_lock_device_interruptible(udev);
580 	if (rc < 0)
581 		return -EINTR;
582 
583 	if (udev->usb3_lpm_u1_enabled)
584 		p = "enabled";
585 	else
586 		p = "disabled";
587 
588 	usb_unlock_device(udev);
589 
590 	return sysfs_emit(buf, "%s\n", p);
591 }
592 static DEVICE_ATTR_RO(usb3_hardware_lpm_u1);
593 
594 static ssize_t usb3_hardware_lpm_u2_show(struct device *dev,
595 				      struct device_attribute *attr, char *buf)
596 {
597 	struct usb_device *udev = to_usb_device(dev);
598 	const char *p;
599 	int rc;
600 
601 	rc = usb_lock_device_interruptible(udev);
602 	if (rc < 0)
603 		return -EINTR;
604 
605 	if (udev->usb3_lpm_u2_enabled)
606 		p = "enabled";
607 	else
608 		p = "disabled";
609 
610 	usb_unlock_device(udev);
611 
612 	return sysfs_emit(buf, "%s\n", p);
613 }
614 static DEVICE_ATTR_RO(usb3_hardware_lpm_u2);
615 
616 static struct attribute *usb2_hardware_lpm_attr[] = {
617 	&dev_attr_usb2_hardware_lpm.attr,
618 	&dev_attr_usb2_lpm_l1_timeout.attr,
619 	&dev_attr_usb2_lpm_besl.attr,
620 	NULL,
621 };
622 static const struct attribute_group usb2_hardware_lpm_attr_group = {
623 	.name	= power_group_name,
624 	.attrs	= usb2_hardware_lpm_attr,
625 };
626 
627 static struct attribute *usb3_hardware_lpm_attr[] = {
628 	&dev_attr_usb3_hardware_lpm_u1.attr,
629 	&dev_attr_usb3_hardware_lpm_u2.attr,
630 	NULL,
631 };
632 static const struct attribute_group usb3_hardware_lpm_attr_group = {
633 	.name	= power_group_name,
634 	.attrs	= usb3_hardware_lpm_attr,
635 };
636 
637 static struct attribute *power_attrs[] = {
638 	&dev_attr_autosuspend.attr,
639 	&dev_attr_level.attr,
640 	&dev_attr_connected_duration.attr,
641 	&dev_attr_active_duration.attr,
642 	NULL,
643 };
644 static const struct attribute_group power_attr_group = {
645 	.name	= power_group_name,
646 	.attrs	= power_attrs,
647 };
648 
649 static int add_power_attributes(struct device *dev)
650 {
651 	int rc = 0;
652 
653 	if (is_usb_device(dev)) {
654 		struct usb_device *udev = to_usb_device(dev);
655 		rc = sysfs_merge_group(&dev->kobj, &power_attr_group);
656 		if (udev->usb2_hw_lpm_capable == 1)
657 			rc = sysfs_merge_group(&dev->kobj,
658 					&usb2_hardware_lpm_attr_group);
659 		if ((udev->speed == USB_SPEED_SUPER ||
660 		     udev->speed == USB_SPEED_SUPER_PLUS) &&
661 				udev->lpm_capable == 1)
662 			rc = sysfs_merge_group(&dev->kobj,
663 					&usb3_hardware_lpm_attr_group);
664 	}
665 
666 	return rc;
667 }
668 
669 static void remove_power_attributes(struct device *dev)
670 {
671 	sysfs_unmerge_group(&dev->kobj, &usb3_hardware_lpm_attr_group);
672 	sysfs_unmerge_group(&dev->kobj, &usb2_hardware_lpm_attr_group);
673 	sysfs_unmerge_group(&dev->kobj, &power_attr_group);
674 }
675 
676 #else
677 
678 #define add_persist_attributes(dev)	0
679 #define remove_persist_attributes(dev)	do {} while (0)
680 
681 #define add_power_attributes(dev)	0
682 #define remove_power_attributes(dev)	do {} while (0)
683 
684 #endif	/* CONFIG_PM */
685 
686 
687 /* Descriptor fields */
688 #define usb_descriptor_attr_le16(field, format_string)			\
689 static ssize_t								\
690 field##_show(struct device *dev, struct device_attribute *attr,	\
691 		char *buf)						\
692 {									\
693 	struct usb_device *udev;					\
694 									\
695 	udev = to_usb_device(dev);					\
696 	return sysfs_emit(buf, format_string,				\
697 			le16_to_cpu(udev->descriptor.field));		\
698 }									\
699 static DEVICE_ATTR_RO(field)
700 
701 usb_descriptor_attr_le16(idVendor, "%04x\n");
702 usb_descriptor_attr_le16(idProduct, "%04x\n");
703 usb_descriptor_attr_le16(bcdDevice, "%04x\n");
704 
705 #define usb_descriptor_attr(field, format_string)			\
706 static ssize_t								\
707 field##_show(struct device *dev, struct device_attribute *attr,	\
708 		char *buf)						\
709 {									\
710 	struct usb_device *udev;					\
711 									\
712 	udev = to_usb_device(dev);					\
713 	return sysfs_emit(buf, format_string, udev->descriptor.field);	\
714 }									\
715 static DEVICE_ATTR_RO(field)
716 
717 usb_descriptor_attr(bDeviceClass, "%02x\n");
718 usb_descriptor_attr(bDeviceSubClass, "%02x\n");
719 usb_descriptor_attr(bDeviceProtocol, "%02x\n");
720 usb_descriptor_attr(bNumConfigurations, "%d\n");
721 usb_descriptor_attr(bMaxPacketSize0, "%d\n");
722 
723 
724 /* show if the device is authorized (1) or not (0) */
725 static ssize_t authorized_show(struct device *dev,
726 			       struct device_attribute *attr, char *buf)
727 {
728 	struct usb_device *usb_dev = to_usb_device(dev);
729 	return sysfs_emit(buf, "%u\n", usb_dev->authorized);
730 }
731 
732 /*
733  * Authorize a device to be used in the system
734  *
735  * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
736  */
737 static ssize_t authorized_store(struct device *dev,
738 				struct device_attribute *attr, const char *buf,
739 				size_t size)
740 {
741 	ssize_t result;
742 	struct usb_device *usb_dev = to_usb_device(dev);
743 	unsigned val;
744 	result = sscanf(buf, "%u\n", &val);
745 	if (result != 1)
746 		result = -EINVAL;
747 	else if (val == 0)
748 		result = usb_deauthorize_device(usb_dev);
749 	else
750 		result = usb_authorize_device(usb_dev);
751 	return result < 0 ? result : size;
752 }
753 static DEVICE_ATTR_IGNORE_LOCKDEP(authorized, S_IRUGO | S_IWUSR,
754 				  authorized_show, authorized_store);
755 
756 /* "Safely remove a device" */
757 static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
758 			    const char *buf, size_t count)
759 {
760 	struct usb_device *udev = to_usb_device(dev);
761 	int rc = 0;
762 
763 	usb_lock_device(udev);
764 	if (udev->state != USB_STATE_NOTATTACHED) {
765 
766 		/* To avoid races, first unconfigure and then remove */
767 		usb_set_configuration(udev, -1);
768 		rc = usb_remove_device(udev);
769 	}
770 	if (rc == 0)
771 		rc = count;
772 	usb_unlock_device(udev);
773 	return rc;
774 }
775 static DEVICE_ATTR_IGNORE_LOCKDEP(remove, S_IWUSR, NULL, remove_store);
776 
777 
778 static struct attribute *dev_attrs[] = {
779 	/* current configuration's attributes */
780 	&dev_attr_configuration.attr,
781 	&dev_attr_bNumInterfaces.attr,
782 	&dev_attr_bConfigurationValue.attr,
783 	&dev_attr_bmAttributes.attr,
784 	&dev_attr_bMaxPower.attr,
785 	/* device attributes */
786 	&dev_attr_urbnum.attr,
787 	&dev_attr_idVendor.attr,
788 	&dev_attr_idProduct.attr,
789 	&dev_attr_bcdDevice.attr,
790 	&dev_attr_bDeviceClass.attr,
791 	&dev_attr_bDeviceSubClass.attr,
792 	&dev_attr_bDeviceProtocol.attr,
793 	&dev_attr_bNumConfigurations.attr,
794 	&dev_attr_bMaxPacketSize0.attr,
795 	&dev_attr_speed.attr,
796 	&dev_attr_rx_lanes.attr,
797 	&dev_attr_tx_lanes.attr,
798 	&dev_attr_busnum.attr,
799 	&dev_attr_devnum.attr,
800 	&dev_attr_devpath.attr,
801 	&dev_attr_version.attr,
802 	&dev_attr_maxchild.attr,
803 	&dev_attr_quirks.attr,
804 	&dev_attr_avoid_reset_quirk.attr,
805 	&dev_attr_authorized.attr,
806 	&dev_attr_remove.attr,
807 	&dev_attr_ltm_capable.attr,
808 #ifdef CONFIG_OF
809 	&dev_attr_devspec.attr,
810 #endif
811 	NULL,
812 };
813 static const struct attribute_group dev_attr_grp = {
814 	.attrs = dev_attrs,
815 };
816 
817 /* When modifying this list, be sure to modify dev_string_attrs_are_visible()
818  * accordingly.
819  */
820 static struct attribute *dev_string_attrs[] = {
821 	&dev_attr_manufacturer.attr,
822 	&dev_attr_product.attr,
823 	&dev_attr_serial.attr,
824 	NULL
825 };
826 
827 static umode_t dev_string_attrs_are_visible(struct kobject *kobj,
828 		struct attribute *a, int n)
829 {
830 	struct device *dev = kobj_to_dev(kobj);
831 	struct usb_device *udev = to_usb_device(dev);
832 
833 	if (a == &dev_attr_manufacturer.attr) {
834 		if (udev->manufacturer == NULL)
835 			return 0;
836 	} else if (a == &dev_attr_product.attr) {
837 		if (udev->product == NULL)
838 			return 0;
839 	} else if (a == &dev_attr_serial.attr) {
840 		if (udev->serial == NULL)
841 			return 0;
842 	}
843 	return a->mode;
844 }
845 
846 static const struct attribute_group dev_string_attr_grp = {
847 	.attrs =	dev_string_attrs,
848 	.is_visible =	dev_string_attrs_are_visible,
849 };
850 
851 const struct attribute_group *usb_device_groups[] = {
852 	&dev_attr_grp,
853 	&dev_string_attr_grp,
854 	NULL
855 };
856 
857 /* Binary descriptors */
858 
859 static ssize_t
860 read_descriptors(struct file *filp, struct kobject *kobj,
861 		struct bin_attribute *attr,
862 		char *buf, loff_t off, size_t count)
863 {
864 	struct device *dev = kobj_to_dev(kobj);
865 	struct usb_device *udev = to_usb_device(dev);
866 	size_t nleft = count;
867 	size_t srclen, n;
868 	int cfgno;
869 	void *src;
870 
871 	/* The binary attribute begins with the device descriptor.
872 	 * Following that are the raw descriptor entries for all the
873 	 * configurations (config plus subsidiary descriptors).
874 	 */
875 	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
876 			nleft > 0; ++cfgno) {
877 		if (cfgno < 0) {
878 			src = &udev->descriptor;
879 			srclen = sizeof(struct usb_device_descriptor);
880 		} else {
881 			src = udev->rawdescriptors[cfgno];
882 			srclen = __le16_to_cpu(udev->config[cfgno].desc.
883 					wTotalLength);
884 		}
885 		if (off < srclen) {
886 			n = min(nleft, srclen - (size_t) off);
887 			memcpy(buf, src + off, n);
888 			nleft -= n;
889 			buf += n;
890 			off = 0;
891 		} else {
892 			off -= srclen;
893 		}
894 	}
895 	return count - nleft;
896 }
897 
898 static struct bin_attribute dev_bin_attr_descriptors = {
899 	.attr = {.name = "descriptors", .mode = 0444},
900 	.read = read_descriptors,
901 	.size = 18 + 65535,	/* dev descr + max-size raw descriptor */
902 };
903 
904 /*
905  * Show & store the current value of authorized_default
906  */
907 static ssize_t authorized_default_show(struct device *dev,
908 				       struct device_attribute *attr, char *buf)
909 {
910 	struct usb_device *rh_usb_dev = to_usb_device(dev);
911 	struct usb_bus *usb_bus = rh_usb_dev->bus;
912 	struct usb_hcd *hcd;
913 
914 	hcd = bus_to_hcd(usb_bus);
915 	return sysfs_emit(buf, "%u\n", hcd->dev_policy);
916 }
917 
918 static ssize_t authorized_default_store(struct device *dev,
919 					struct device_attribute *attr,
920 					const char *buf, size_t size)
921 {
922 	ssize_t result;
923 	unsigned int val;
924 	struct usb_device *rh_usb_dev = to_usb_device(dev);
925 	struct usb_bus *usb_bus = rh_usb_dev->bus;
926 	struct usb_hcd *hcd;
927 
928 	hcd = bus_to_hcd(usb_bus);
929 	result = sscanf(buf, "%u\n", &val);
930 	if (result == 1) {
931 		hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ?
932 			val : USB_DEVICE_AUTHORIZE_ALL;
933 		result = size;
934 	} else {
935 		result = -EINVAL;
936 	}
937 	return result;
938 }
939 static DEVICE_ATTR_RW(authorized_default);
940 
941 /*
942  * interface_authorized_default_show - show default authorization status
943  * for USB interfaces
944  *
945  * note: interface_authorized_default is the default value
946  *       for initializing the authorized attribute of interfaces
947  */
948 static ssize_t interface_authorized_default_show(struct device *dev,
949 		struct device_attribute *attr, char *buf)
950 {
951 	struct usb_device *usb_dev = to_usb_device(dev);
952 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
953 
954 	return sysfs_emit(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
955 }
956 
957 /*
958  * interface_authorized_default_store - store default authorization status
959  * for USB interfaces
960  *
961  * note: interface_authorized_default is the default value
962  *       for initializing the authorized attribute of interfaces
963  */
964 static ssize_t interface_authorized_default_store(struct device *dev,
965 		struct device_attribute *attr, const char *buf, size_t count)
966 {
967 	struct usb_device *usb_dev = to_usb_device(dev);
968 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
969 	int rc = count;
970 	bool val;
971 
972 	if (kstrtobool(buf, &val) != 0)
973 		return -EINVAL;
974 
975 	if (val)
976 		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
977 	else
978 		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
979 
980 	return rc;
981 }
982 static DEVICE_ATTR_RW(interface_authorized_default);
983 
984 /* Group all the USB bus attributes */
985 static struct attribute *usb_bus_attrs[] = {
986 		&dev_attr_authorized_default.attr,
987 		&dev_attr_interface_authorized_default.attr,
988 		NULL,
989 };
990 
991 static const struct attribute_group usb_bus_attr_group = {
992 	.name = NULL,	/* we want them in the same directory */
993 	.attrs = usb_bus_attrs,
994 };
995 
996 
997 static int add_default_authorized_attributes(struct device *dev)
998 {
999 	int rc = 0;
1000 
1001 	if (is_usb_device(dev))
1002 		rc = sysfs_create_group(&dev->kobj, &usb_bus_attr_group);
1003 
1004 	return rc;
1005 }
1006 
1007 static void remove_default_authorized_attributes(struct device *dev)
1008 {
1009 	if (is_usb_device(dev)) {
1010 		sysfs_remove_group(&dev->kobj, &usb_bus_attr_group);
1011 	}
1012 }
1013 
1014 int usb_create_sysfs_dev_files(struct usb_device *udev)
1015 {
1016 	struct device *dev = &udev->dev;
1017 	int retval;
1018 
1019 	retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
1020 	if (retval)
1021 		goto error;
1022 
1023 	retval = add_persist_attributes(dev);
1024 	if (retval)
1025 		goto error;
1026 
1027 	retval = add_power_attributes(dev);
1028 	if (retval)
1029 		goto error;
1030 
1031 	if (is_root_hub(udev)) {
1032 		retval = add_default_authorized_attributes(dev);
1033 		if (retval)
1034 			goto error;
1035 	}
1036 	return retval;
1037 
1038 error:
1039 	usb_remove_sysfs_dev_files(udev);
1040 	return retval;
1041 }
1042 
1043 void usb_remove_sysfs_dev_files(struct usb_device *udev)
1044 {
1045 	struct device *dev = &udev->dev;
1046 
1047 	if (is_root_hub(udev))
1048 		remove_default_authorized_attributes(dev);
1049 
1050 	remove_power_attributes(dev);
1051 	remove_persist_attributes(dev);
1052 	device_remove_bin_file(dev, &dev_bin_attr_descriptors);
1053 }
1054 
1055 /* Interface Association Descriptor fields */
1056 #define usb_intf_assoc_attr(field, format_string)			\
1057 static ssize_t								\
1058 iad_##field##_show(struct device *dev, struct device_attribute *attr,	\
1059 		char *buf)						\
1060 {									\
1061 	struct usb_interface *intf = to_usb_interface(dev);		\
1062 									\
1063 	return sysfs_emit(buf, format_string,				\
1064 			intf->intf_assoc->field); 			\
1065 }									\
1066 static DEVICE_ATTR_RO(iad_##field)
1067 
1068 usb_intf_assoc_attr(bFirstInterface, "%02x\n");
1069 usb_intf_assoc_attr(bInterfaceCount, "%02d\n");
1070 usb_intf_assoc_attr(bFunctionClass, "%02x\n");
1071 usb_intf_assoc_attr(bFunctionSubClass, "%02x\n");
1072 usb_intf_assoc_attr(bFunctionProtocol, "%02x\n");
1073 
1074 /* Interface fields */
1075 #define usb_intf_attr(field, format_string)				\
1076 static ssize_t								\
1077 field##_show(struct device *dev, struct device_attribute *attr,		\
1078 		char *buf)						\
1079 {									\
1080 	struct usb_interface *intf = to_usb_interface(dev);		\
1081 									\
1082 	return sysfs_emit(buf, format_string,				\
1083 			intf->cur_altsetting->desc.field); 		\
1084 }									\
1085 static DEVICE_ATTR_RO(field)
1086 
1087 usb_intf_attr(bInterfaceNumber, "%02x\n");
1088 usb_intf_attr(bAlternateSetting, "%2d\n");
1089 usb_intf_attr(bNumEndpoints, "%02x\n");
1090 usb_intf_attr(bInterfaceClass, "%02x\n");
1091 usb_intf_attr(bInterfaceSubClass, "%02x\n");
1092 usb_intf_attr(bInterfaceProtocol, "%02x\n");
1093 
1094 static ssize_t interface_show(struct device *dev, struct device_attribute *attr,
1095 			      char *buf)
1096 {
1097 	struct usb_interface *intf;
1098 	char *string;
1099 
1100 	intf = to_usb_interface(dev);
1101 	string = READ_ONCE(intf->cur_altsetting->string);
1102 	if (!string)
1103 		return 0;
1104 	return sysfs_emit(buf, "%s\n", string);
1105 }
1106 static DEVICE_ATTR_RO(interface);
1107 
1108 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
1109 			     char *buf)
1110 {
1111 	struct usb_interface *intf;
1112 	struct usb_device *udev;
1113 	struct usb_host_interface *alt;
1114 
1115 	intf = to_usb_interface(dev);
1116 	udev = interface_to_usbdev(intf);
1117 	alt = READ_ONCE(intf->cur_altsetting);
1118 
1119 	return sysfs_emit(buf,
1120 			"usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
1121 			"ic%02Xisc%02Xip%02Xin%02X\n",
1122 			le16_to_cpu(udev->descriptor.idVendor),
1123 			le16_to_cpu(udev->descriptor.idProduct),
1124 			le16_to_cpu(udev->descriptor.bcdDevice),
1125 			udev->descriptor.bDeviceClass,
1126 			udev->descriptor.bDeviceSubClass,
1127 			udev->descriptor.bDeviceProtocol,
1128 			alt->desc.bInterfaceClass,
1129 			alt->desc.bInterfaceSubClass,
1130 			alt->desc.bInterfaceProtocol,
1131 			alt->desc.bInterfaceNumber);
1132 }
1133 static DEVICE_ATTR_RO(modalias);
1134 
1135 static ssize_t supports_autosuspend_show(struct device *dev,
1136 					 struct device_attribute *attr,
1137 					 char *buf)
1138 {
1139 	int s;
1140 
1141 	s = device_lock_interruptible(dev);
1142 	if (s < 0)
1143 		return -EINTR;
1144 	/* Devices will be autosuspended even when an interface isn't claimed */
1145 	s = (!dev->driver || to_usb_driver(dev->driver)->supports_autosuspend);
1146 	device_unlock(dev);
1147 
1148 	return sysfs_emit(buf, "%u\n", s);
1149 }
1150 static DEVICE_ATTR_RO(supports_autosuspend);
1151 
1152 /*
1153  * interface_authorized_show - show authorization status of an USB interface
1154  * 1 is authorized, 0 is deauthorized
1155  */
1156 static ssize_t interface_authorized_show(struct device *dev,
1157 		struct device_attribute *attr, char *buf)
1158 {
1159 	struct usb_interface *intf = to_usb_interface(dev);
1160 
1161 	return sysfs_emit(buf, "%u\n", intf->authorized);
1162 }
1163 
1164 /*
1165  * interface_authorized_store - authorize or deauthorize an USB interface
1166  */
1167 static ssize_t interface_authorized_store(struct device *dev,
1168 		struct device_attribute *attr, const char *buf, size_t count)
1169 {
1170 	struct usb_interface *intf = to_usb_interface(dev);
1171 	bool val;
1172 	struct kernfs_node *kn;
1173 
1174 	if (kstrtobool(buf, &val) != 0)
1175 		return -EINVAL;
1176 
1177 	if (val) {
1178 		usb_authorize_interface(intf);
1179 	} else {
1180 		/*
1181 		 * Prevent deadlock if another process is concurrently
1182 		 * trying to unregister intf.
1183 		 */
1184 		kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
1185 		if (kn) {
1186 			usb_deauthorize_interface(intf);
1187 			sysfs_unbreak_active_protection(kn);
1188 		}
1189 	}
1190 
1191 	return count;
1192 }
1193 static struct device_attribute dev_attr_interface_authorized =
1194 		__ATTR(authorized, S_IRUGO | S_IWUSR,
1195 		interface_authorized_show, interface_authorized_store);
1196 
1197 static struct attribute *intf_attrs[] = {
1198 	&dev_attr_bInterfaceNumber.attr,
1199 	&dev_attr_bAlternateSetting.attr,
1200 	&dev_attr_bNumEndpoints.attr,
1201 	&dev_attr_bInterfaceClass.attr,
1202 	&dev_attr_bInterfaceSubClass.attr,
1203 	&dev_attr_bInterfaceProtocol.attr,
1204 	&dev_attr_modalias.attr,
1205 	&dev_attr_supports_autosuspend.attr,
1206 	&dev_attr_interface_authorized.attr,
1207 	NULL,
1208 };
1209 static const struct attribute_group intf_attr_grp = {
1210 	.attrs = intf_attrs,
1211 };
1212 
1213 static struct attribute *intf_assoc_attrs[] = {
1214 	&dev_attr_iad_bFirstInterface.attr,
1215 	&dev_attr_iad_bInterfaceCount.attr,
1216 	&dev_attr_iad_bFunctionClass.attr,
1217 	&dev_attr_iad_bFunctionSubClass.attr,
1218 	&dev_attr_iad_bFunctionProtocol.attr,
1219 	NULL,
1220 };
1221 
1222 static umode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
1223 		struct attribute *a, int n)
1224 {
1225 	struct device *dev = kobj_to_dev(kobj);
1226 	struct usb_interface *intf = to_usb_interface(dev);
1227 
1228 	if (intf->intf_assoc == NULL)
1229 		return 0;
1230 	return a->mode;
1231 }
1232 
1233 static const struct attribute_group intf_assoc_attr_grp = {
1234 	.attrs =	intf_assoc_attrs,
1235 	.is_visible =	intf_assoc_attrs_are_visible,
1236 };
1237 
1238 static ssize_t wireless_status_show(struct device *dev,
1239 				    struct device_attribute *attr, char *buf)
1240 {
1241 	struct usb_interface *intf;
1242 
1243 	intf = to_usb_interface(dev);
1244 	if (intf->wireless_status == USB_WIRELESS_STATUS_DISCONNECTED)
1245 		return sysfs_emit(buf, "%s\n", "disconnected");
1246 	return sysfs_emit(buf, "%s\n", "connected");
1247 }
1248 static DEVICE_ATTR_RO(wireless_status);
1249 
1250 static struct attribute *intf_wireless_status_attrs[] = {
1251 	&dev_attr_wireless_status.attr,
1252 	NULL
1253 };
1254 
1255 static umode_t intf_wireless_status_attr_is_visible(struct kobject *kobj,
1256 		struct attribute *a, int n)
1257 {
1258 	struct device *dev = kobj_to_dev(kobj);
1259 	struct usb_interface *intf = to_usb_interface(dev);
1260 
1261 	if (a != &dev_attr_wireless_status.attr ||
1262 	    intf->wireless_status != USB_WIRELESS_STATUS_NA)
1263 		return a->mode;
1264 	return 0;
1265 }
1266 
1267 static const struct attribute_group intf_wireless_status_attr_grp = {
1268 	.attrs =	intf_wireless_status_attrs,
1269 	.is_visible =	intf_wireless_status_attr_is_visible,
1270 };
1271 
1272 int usb_update_wireless_status_attr(struct usb_interface *intf)
1273 {
1274 	struct device *dev = &intf->dev;
1275 	int ret;
1276 
1277 	ret = sysfs_update_group(&dev->kobj, &intf_wireless_status_attr_grp);
1278 	if (ret < 0)
1279 		return ret;
1280 
1281 	sysfs_notify(&dev->kobj, NULL, "wireless_status");
1282 	kobject_uevent(&dev->kobj, KOBJ_CHANGE);
1283 
1284 	return 0;
1285 }
1286 
1287 const struct attribute_group *usb_interface_groups[] = {
1288 	&intf_attr_grp,
1289 	&intf_assoc_attr_grp,
1290 	&intf_wireless_status_attr_grp,
1291 	NULL
1292 };
1293 
1294 void usb_create_sysfs_intf_files(struct usb_interface *intf)
1295 {
1296 	struct usb_device *udev = interface_to_usbdev(intf);
1297 	struct usb_host_interface *alt = intf->cur_altsetting;
1298 
1299 	if (intf->sysfs_files_created || intf->unregistering)
1300 		return;
1301 
1302 	if (!alt->string && !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
1303 		alt->string = usb_cache_string(udev, alt->desc.iInterface);
1304 	if (alt->string && device_create_file(&intf->dev, &dev_attr_interface)) {
1305 		/* This is not a serious error */
1306 		dev_dbg(&intf->dev, "interface string descriptor file not created\n");
1307 	}
1308 	intf->sysfs_files_created = 1;
1309 }
1310 
1311 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
1312 {
1313 	if (!intf->sysfs_files_created)
1314 		return;
1315 
1316 	device_remove_file(&intf->dev, &dev_attr_interface);
1317 	intf->sysfs_files_created = 0;
1318 }
1319