xref: /openbmc/linux/drivers/usb/core/sysfs.c (revision 929e2a61)
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/string.h>
17 #include <linux/usb.h>
18 #include <linux/usb/hcd.h>
19 #include <linux/usb/quirks.h>
20 #include <linux/of.h>
21 #include "usb.h"
22 
23 /* Active configuration fields */
24 #define usb_actconfig_show(field, format_string)			\
25 static ssize_t field##_show(struct device *dev,				\
26 			    struct device_attribute *attr, char *buf)	\
27 {									\
28 	struct usb_device *udev;					\
29 	struct usb_host_config *actconfig;				\
30 	ssize_t rc;							\
31 									\
32 	udev = to_usb_device(dev);					\
33 	rc = usb_lock_device_interruptible(udev);			\
34 	if (rc < 0)							\
35 		return -EINTR;						\
36 	actconfig = udev->actconfig;					\
37 	if (actconfig)							\
38 		rc = sprintf(buf, format_string,			\
39 				actconfig->desc.field);			\
40 	usb_unlock_device(udev);					\
41 	return rc;							\
42 }									\
43 
44 #define usb_actconfig_attr(field, format_string)		\
45 	usb_actconfig_show(field, format_string)		\
46 	static DEVICE_ATTR_RO(field)
47 
48 usb_actconfig_attr(bNumInterfaces, "%2d\n");
49 usb_actconfig_attr(bmAttributes, "%2x\n");
50 
51 static ssize_t bMaxPower_show(struct device *dev,
52 		struct device_attribute *attr, char *buf)
53 {
54 	struct usb_device *udev;
55 	struct usb_host_config *actconfig;
56 	ssize_t rc;
57 
58 	udev = to_usb_device(dev);
59 	rc = usb_lock_device_interruptible(udev);
60 	if (rc < 0)
61 		return -EINTR;
62 	actconfig = udev->actconfig;
63 	if (actconfig)
64 		rc = sprintf(buf, "%dmA\n", usb_get_max_power(udev, actconfig));
65 	usb_unlock_device(udev);
66 	return rc;
67 }
68 static DEVICE_ATTR_RO(bMaxPower);
69 
70 static ssize_t configuration_show(struct device *dev,
71 		struct device_attribute *attr, char *buf)
72 {
73 	struct usb_device *udev;
74 	struct usb_host_config *actconfig;
75 	ssize_t rc;
76 
77 	udev = to_usb_device(dev);
78 	rc = usb_lock_device_interruptible(udev);
79 	if (rc < 0)
80 		return -EINTR;
81 	actconfig = udev->actconfig;
82 	if (actconfig && actconfig->string)
83 		rc = sprintf(buf, "%s\n", actconfig->string);
84 	usb_unlock_device(udev);
85 	return rc;
86 }
87 static DEVICE_ATTR_RO(configuration);
88 
89 /* configuration value is always present, and r/w */
90 usb_actconfig_show(bConfigurationValue, "%u\n");
91 
92 static ssize_t bConfigurationValue_store(struct device *dev,
93 					 struct device_attribute *attr,
94 					 const char *buf, size_t count)
95 {
96 	struct usb_device	*udev = to_usb_device(dev);
97 	int			config, value, rc;
98 
99 	if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
100 		return -EINVAL;
101 	rc = usb_lock_device_interruptible(udev);
102 	if (rc < 0)
103 		return -EINTR;
104 	value = usb_set_configuration(udev, config);
105 	usb_unlock_device(udev);
106 	return (value < 0) ? value : count;
107 }
108 static DEVICE_ATTR_IGNORE_LOCKDEP(bConfigurationValue, S_IRUGO | S_IWUSR,
109 		bConfigurationValue_show, bConfigurationValue_store);
110 
111 #ifdef CONFIG_OF
112 static ssize_t devspec_show(struct device *dev, struct device_attribute *attr,
113 			    char *buf)
114 {
115 	struct device_node *of_node = dev->of_node;
116 
117 	return sprintf(buf, "%pOF\n", of_node);
118 }
119 static DEVICE_ATTR_RO(devspec);
120 #endif
121 
122 /* String fields */
123 #define usb_string_attr(name)						\
124 static ssize_t  name##_show(struct device *dev,				\
125 		struct device_attribute *attr, char *buf)		\
126 {									\
127 	struct usb_device *udev;					\
128 	int retval;							\
129 									\
130 	udev = to_usb_device(dev);					\
131 	retval = usb_lock_device_interruptible(udev);			\
132 	if (retval < 0)							\
133 		return -EINTR;						\
134 	retval = sprintf(buf, "%s\n", udev->name);			\
135 	usb_unlock_device(udev);					\
136 	return retval;							\
137 }									\
138 static DEVICE_ATTR_RO(name)
139 
140 usb_string_attr(product);
141 usb_string_attr(manufacturer);
142 usb_string_attr(serial);
143 
144 static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
145 			  char *buf)
146 {
147 	struct usb_device *udev;
148 	char *speed;
149 
150 	udev = to_usb_device(dev);
151 
152 	switch (udev->speed) {
153 	case USB_SPEED_LOW:
154 		speed = "1.5";
155 		break;
156 	case USB_SPEED_UNKNOWN:
157 	case USB_SPEED_FULL:
158 		speed = "12";
159 		break;
160 	case USB_SPEED_HIGH:
161 		speed = "480";
162 		break;
163 	case USB_SPEED_WIRELESS:
164 		speed = "480";
165 		break;
166 	case USB_SPEED_SUPER:
167 		speed = "5000";
168 		break;
169 	case USB_SPEED_SUPER_PLUS:
170 		speed = "10000";
171 		break;
172 	default:
173 		speed = "unknown";
174 	}
175 	return sprintf(buf, "%s\n", speed);
176 }
177 static DEVICE_ATTR_RO(speed);
178 
179 static ssize_t rx_lanes_show(struct device *dev, struct device_attribute *attr,
180 			  char *buf)
181 {
182 	struct usb_device *udev;
183 
184 	udev = to_usb_device(dev);
185 	return sprintf(buf, "%d\n", udev->rx_lanes);
186 }
187 static DEVICE_ATTR_RO(rx_lanes);
188 
189 static ssize_t tx_lanes_show(struct device *dev, struct device_attribute *attr,
190 			  char *buf)
191 {
192 	struct usb_device *udev;
193 
194 	udev = to_usb_device(dev);
195 	return sprintf(buf, "%d\n", udev->tx_lanes);
196 }
197 static DEVICE_ATTR_RO(tx_lanes);
198 
199 static ssize_t busnum_show(struct device *dev, struct device_attribute *attr,
200 			   char *buf)
201 {
202 	struct usb_device *udev;
203 
204 	udev = to_usb_device(dev);
205 	return sprintf(buf, "%d\n", udev->bus->busnum);
206 }
207 static DEVICE_ATTR_RO(busnum);
208 
209 static ssize_t devnum_show(struct device *dev, struct device_attribute *attr,
210 			   char *buf)
211 {
212 	struct usb_device *udev;
213 
214 	udev = to_usb_device(dev);
215 	return sprintf(buf, "%d\n", udev->devnum);
216 }
217 static DEVICE_ATTR_RO(devnum);
218 
219 static ssize_t devpath_show(struct device *dev, struct device_attribute *attr,
220 			    char *buf)
221 {
222 	struct usb_device *udev;
223 
224 	udev = to_usb_device(dev);
225 	return sprintf(buf, "%s\n", udev->devpath);
226 }
227 static DEVICE_ATTR_RO(devpath);
228 
229 static ssize_t version_show(struct device *dev, struct device_attribute *attr,
230 			    char *buf)
231 {
232 	struct usb_device *udev;
233 	u16 bcdUSB;
234 
235 	udev = to_usb_device(dev);
236 	bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
237 	return sprintf(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
238 }
239 static DEVICE_ATTR_RO(version);
240 
241 static ssize_t maxchild_show(struct device *dev, struct device_attribute *attr,
242 			     char *buf)
243 {
244 	struct usb_device *udev;
245 
246 	udev = to_usb_device(dev);
247 	return sprintf(buf, "%d\n", udev->maxchild);
248 }
249 static DEVICE_ATTR_RO(maxchild);
250 
251 static ssize_t quirks_show(struct device *dev, struct device_attribute *attr,
252 			   char *buf)
253 {
254 	struct usb_device *udev;
255 
256 	udev = to_usb_device(dev);
257 	return sprintf(buf, "0x%x\n", udev->quirks);
258 }
259 static DEVICE_ATTR_RO(quirks);
260 
261 static ssize_t avoid_reset_quirk_show(struct device *dev,
262 				      struct device_attribute *attr, char *buf)
263 {
264 	struct usb_device *udev;
265 
266 	udev = to_usb_device(dev);
267 	return sprintf(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET));
268 }
269 
270 static ssize_t avoid_reset_quirk_store(struct device *dev,
271 				      struct device_attribute *attr,
272 				      const char *buf, size_t count)
273 {
274 	struct usb_device	*udev = to_usb_device(dev);
275 	int			val, rc;
276 
277 	if (sscanf(buf, "%d", &val) != 1 || val < 0 || val > 1)
278 		return -EINVAL;
279 	rc = usb_lock_device_interruptible(udev);
280 	if (rc < 0)
281 		return -EINTR;
282 	if (val)
283 		udev->quirks |= USB_QUIRK_RESET;
284 	else
285 		udev->quirks &= ~USB_QUIRK_RESET;
286 	usb_unlock_device(udev);
287 	return count;
288 }
289 static DEVICE_ATTR_RW(avoid_reset_quirk);
290 
291 static ssize_t urbnum_show(struct device *dev, struct device_attribute *attr,
292 			   char *buf)
293 {
294 	struct usb_device *udev;
295 
296 	udev = to_usb_device(dev);
297 	return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
298 }
299 static DEVICE_ATTR_RO(urbnum);
300 
301 static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
302 			      char *buf)
303 {
304 	struct usb_device *udev;
305 	char *state;
306 
307 	udev = to_usb_device(dev);
308 
309 	switch (udev->removable) {
310 	case USB_DEVICE_REMOVABLE:
311 		state = "removable";
312 		break;
313 	case USB_DEVICE_FIXED:
314 		state = "fixed";
315 		break;
316 	default:
317 		state = "unknown";
318 	}
319 
320 	return sprintf(buf, "%s\n", state);
321 }
322 static DEVICE_ATTR_RO(removable);
323 
324 static ssize_t ltm_capable_show(struct device *dev,
325 				struct device_attribute *attr, char *buf)
326 {
327 	if (usb_device_supports_ltm(to_usb_device(dev)))
328 		return sprintf(buf, "%s\n", "yes");
329 	return sprintf(buf, "%s\n", "no");
330 }
331 static DEVICE_ATTR_RO(ltm_capable);
332 
333 #ifdef	CONFIG_PM
334 
335 static ssize_t persist_show(struct device *dev, struct device_attribute *attr,
336 			    char *buf)
337 {
338 	struct usb_device *udev = to_usb_device(dev);
339 
340 	return sprintf(buf, "%d\n", udev->persist_enabled);
341 }
342 
343 static ssize_t persist_store(struct device *dev, struct device_attribute *attr,
344 			     const char *buf, size_t count)
345 {
346 	struct usb_device *udev = to_usb_device(dev);
347 	int value, rc;
348 
349 	/* Hubs are always enabled for USB_PERSIST */
350 	if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
351 		return -EPERM;
352 
353 	if (sscanf(buf, "%d", &value) != 1)
354 		return -EINVAL;
355 
356 	rc = usb_lock_device_interruptible(udev);
357 	if (rc < 0)
358 		return -EINTR;
359 	udev->persist_enabled = !!value;
360 	usb_unlock_device(udev);
361 	return count;
362 }
363 static DEVICE_ATTR_RW(persist);
364 
365 static int add_persist_attributes(struct device *dev)
366 {
367 	int rc = 0;
368 
369 	if (is_usb_device(dev)) {
370 		struct usb_device *udev = to_usb_device(dev);
371 
372 		/* Hubs are automatically enabled for USB_PERSIST,
373 		 * no point in creating the attribute file.
374 		 */
375 		if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
376 			rc = sysfs_add_file_to_group(&dev->kobj,
377 					&dev_attr_persist.attr,
378 					power_group_name);
379 	}
380 	return rc;
381 }
382 
383 static void remove_persist_attributes(struct device *dev)
384 {
385 	sysfs_remove_file_from_group(&dev->kobj,
386 			&dev_attr_persist.attr,
387 			power_group_name);
388 }
389 
390 static ssize_t connected_duration_show(struct device *dev,
391 				       struct device_attribute *attr, char *buf)
392 {
393 	struct usb_device *udev = to_usb_device(dev);
394 
395 	return sprintf(buf, "%u\n",
396 			jiffies_to_msecs(jiffies - udev->connect_time));
397 }
398 static DEVICE_ATTR_RO(connected_duration);
399 
400 /*
401  * If the device is resumed, the last time the device was suspended has
402  * been pre-subtracted from active_duration.  We add the current time to
403  * get the duration that the device was actually active.
404  *
405  * If the device is suspended, the active_duration is up-to-date.
406  */
407 static ssize_t active_duration_show(struct device *dev,
408 				    struct device_attribute *attr, char *buf)
409 {
410 	struct usb_device *udev = to_usb_device(dev);
411 	int duration;
412 
413 	if (udev->state != USB_STATE_SUSPENDED)
414 		duration = jiffies_to_msecs(jiffies + udev->active_duration);
415 	else
416 		duration = jiffies_to_msecs(udev->active_duration);
417 	return sprintf(buf, "%u\n", duration);
418 }
419 static DEVICE_ATTR_RO(active_duration);
420 
421 static ssize_t autosuspend_show(struct device *dev,
422 				struct device_attribute *attr, char *buf)
423 {
424 	return sprintf(buf, "%d\n", dev->power.autosuspend_delay / 1000);
425 }
426 
427 static ssize_t autosuspend_store(struct device *dev,
428 				 struct device_attribute *attr, const char *buf,
429 				 size_t count)
430 {
431 	int value;
432 
433 	if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/1000 ||
434 			value <= -INT_MAX/1000)
435 		return -EINVAL;
436 
437 	pm_runtime_set_autosuspend_delay(dev, value * 1000);
438 	return count;
439 }
440 static DEVICE_ATTR_RW(autosuspend);
441 
442 static const char on_string[] = "on";
443 static const char auto_string[] = "auto";
444 
445 static void warn_level(void)
446 {
447 	static int level_warned;
448 
449 	if (!level_warned) {
450 		level_warned = 1;
451 		printk(KERN_WARNING "WARNING! power/level is deprecated; "
452 				"use power/control instead\n");
453 	}
454 }
455 
456 static ssize_t level_show(struct device *dev, struct device_attribute *attr,
457 			  char *buf)
458 {
459 	struct usb_device *udev = to_usb_device(dev);
460 	const char *p = auto_string;
461 
462 	warn_level();
463 	if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
464 		p = on_string;
465 	return sprintf(buf, "%s\n", p);
466 }
467 
468 static ssize_t level_store(struct device *dev, struct device_attribute *attr,
469 			   const char *buf, size_t count)
470 {
471 	struct usb_device *udev = to_usb_device(dev);
472 	int len = count;
473 	char *cp;
474 	int rc = count;
475 	int rv;
476 
477 	warn_level();
478 	cp = memchr(buf, '\n', count);
479 	if (cp)
480 		len = cp - buf;
481 
482 	rv = usb_lock_device_interruptible(udev);
483 	if (rv < 0)
484 		return -EINTR;
485 
486 	if (len == sizeof on_string - 1 &&
487 			strncmp(buf, on_string, len) == 0)
488 		usb_disable_autosuspend(udev);
489 
490 	else if (len == sizeof auto_string - 1 &&
491 			strncmp(buf, auto_string, len) == 0)
492 		usb_enable_autosuspend(udev);
493 
494 	else
495 		rc = -EINVAL;
496 
497 	usb_unlock_device(udev);
498 	return rc;
499 }
500 static DEVICE_ATTR_RW(level);
501 
502 static ssize_t usb2_hardware_lpm_show(struct device *dev,
503 				      struct device_attribute *attr, char *buf)
504 {
505 	struct usb_device *udev = to_usb_device(dev);
506 	const char *p;
507 
508 	if (udev->usb2_hw_lpm_allowed == 1)
509 		p = "enabled";
510 	else
511 		p = "disabled";
512 
513 	return sprintf(buf, "%s\n", p);
514 }
515 
516 static ssize_t usb2_hardware_lpm_store(struct device *dev,
517 				       struct device_attribute *attr,
518 				       const char *buf, size_t count)
519 {
520 	struct usb_device *udev = to_usb_device(dev);
521 	bool value;
522 	int ret;
523 
524 	ret = usb_lock_device_interruptible(udev);
525 	if (ret < 0)
526 		return -EINTR;
527 
528 	ret = strtobool(buf, &value);
529 
530 	if (!ret) {
531 		udev->usb2_hw_lpm_allowed = value;
532 		if (value)
533 			ret = usb_enable_usb2_hardware_lpm(udev);
534 		else
535 			ret = usb_disable_usb2_hardware_lpm(udev);
536 	}
537 
538 	usb_unlock_device(udev);
539 
540 	if (!ret)
541 		return count;
542 
543 	return ret;
544 }
545 static DEVICE_ATTR_RW(usb2_hardware_lpm);
546 
547 static ssize_t usb2_lpm_l1_timeout_show(struct device *dev,
548 					struct device_attribute *attr,
549 					char *buf)
550 {
551 	struct usb_device *udev = to_usb_device(dev);
552 	return sprintf(buf, "%d\n", udev->l1_params.timeout);
553 }
554 
555 static ssize_t usb2_lpm_l1_timeout_store(struct device *dev,
556 					 struct device_attribute *attr,
557 					 const char *buf, size_t count)
558 {
559 	struct usb_device *udev = to_usb_device(dev);
560 	u16 timeout;
561 
562 	if (kstrtou16(buf, 0, &timeout))
563 		return -EINVAL;
564 
565 	udev->l1_params.timeout = timeout;
566 
567 	return count;
568 }
569 static DEVICE_ATTR_RW(usb2_lpm_l1_timeout);
570 
571 static ssize_t usb2_lpm_besl_show(struct device *dev,
572 				  struct device_attribute *attr, char *buf)
573 {
574 	struct usb_device *udev = to_usb_device(dev);
575 	return sprintf(buf, "%d\n", udev->l1_params.besl);
576 }
577 
578 static ssize_t usb2_lpm_besl_store(struct device *dev,
579 				   struct device_attribute *attr,
580 				   const char *buf, size_t count)
581 {
582 	struct usb_device *udev = to_usb_device(dev);
583 	u8 besl;
584 
585 	if (kstrtou8(buf, 0, &besl) || besl > 15)
586 		return -EINVAL;
587 
588 	udev->l1_params.besl = besl;
589 
590 	return count;
591 }
592 static DEVICE_ATTR_RW(usb2_lpm_besl);
593 
594 static ssize_t usb3_hardware_lpm_u1_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_u1_enabled)
606 		p = "enabled";
607 	else
608 		p = "disabled";
609 
610 	usb_unlock_device(udev);
611 
612 	return sprintf(buf, "%s\n", p);
613 }
614 static DEVICE_ATTR_RO(usb3_hardware_lpm_u1);
615 
616 static ssize_t usb3_hardware_lpm_u2_show(struct device *dev,
617 				      struct device_attribute *attr, char *buf)
618 {
619 	struct usb_device *udev = to_usb_device(dev);
620 	const char *p;
621 	int rc;
622 
623 	rc = usb_lock_device_interruptible(udev);
624 	if (rc < 0)
625 		return -EINTR;
626 
627 	if (udev->usb3_lpm_u2_enabled)
628 		p = "enabled";
629 	else
630 		p = "disabled";
631 
632 	usb_unlock_device(udev);
633 
634 	return sprintf(buf, "%s\n", p);
635 }
636 static DEVICE_ATTR_RO(usb3_hardware_lpm_u2);
637 
638 static struct attribute *usb2_hardware_lpm_attr[] = {
639 	&dev_attr_usb2_hardware_lpm.attr,
640 	&dev_attr_usb2_lpm_l1_timeout.attr,
641 	&dev_attr_usb2_lpm_besl.attr,
642 	NULL,
643 };
644 static struct attribute_group usb2_hardware_lpm_attr_group = {
645 	.name	= power_group_name,
646 	.attrs	= usb2_hardware_lpm_attr,
647 };
648 
649 static struct attribute *usb3_hardware_lpm_attr[] = {
650 	&dev_attr_usb3_hardware_lpm_u1.attr,
651 	&dev_attr_usb3_hardware_lpm_u2.attr,
652 	NULL,
653 };
654 static struct attribute_group usb3_hardware_lpm_attr_group = {
655 	.name	= power_group_name,
656 	.attrs	= usb3_hardware_lpm_attr,
657 };
658 
659 static struct attribute *power_attrs[] = {
660 	&dev_attr_autosuspend.attr,
661 	&dev_attr_level.attr,
662 	&dev_attr_connected_duration.attr,
663 	&dev_attr_active_duration.attr,
664 	NULL,
665 };
666 static struct attribute_group power_attr_group = {
667 	.name	= power_group_name,
668 	.attrs	= power_attrs,
669 };
670 
671 static int add_power_attributes(struct device *dev)
672 {
673 	int rc = 0;
674 
675 	if (is_usb_device(dev)) {
676 		struct usb_device *udev = to_usb_device(dev);
677 		rc = sysfs_merge_group(&dev->kobj, &power_attr_group);
678 		if (udev->usb2_hw_lpm_capable == 1)
679 			rc = sysfs_merge_group(&dev->kobj,
680 					&usb2_hardware_lpm_attr_group);
681 		if ((udev->speed == USB_SPEED_SUPER ||
682 		     udev->speed == USB_SPEED_SUPER_PLUS) &&
683 				udev->lpm_capable == 1)
684 			rc = sysfs_merge_group(&dev->kobj,
685 					&usb3_hardware_lpm_attr_group);
686 	}
687 
688 	return rc;
689 }
690 
691 static void remove_power_attributes(struct device *dev)
692 {
693 	sysfs_unmerge_group(&dev->kobj, &usb2_hardware_lpm_attr_group);
694 	sysfs_unmerge_group(&dev->kobj, &power_attr_group);
695 }
696 
697 #else
698 
699 #define add_persist_attributes(dev)	0
700 #define remove_persist_attributes(dev)	do {} while (0)
701 
702 #define add_power_attributes(dev)	0
703 #define remove_power_attributes(dev)	do {} while (0)
704 
705 #endif	/* CONFIG_PM */
706 
707 
708 /* Descriptor fields */
709 #define usb_descriptor_attr_le16(field, format_string)			\
710 static ssize_t								\
711 field##_show(struct device *dev, struct device_attribute *attr,	\
712 		char *buf)						\
713 {									\
714 	struct usb_device *udev;					\
715 									\
716 	udev = to_usb_device(dev);					\
717 	return sprintf(buf, format_string, 				\
718 			le16_to_cpu(udev->descriptor.field));		\
719 }									\
720 static DEVICE_ATTR_RO(field)
721 
722 usb_descriptor_attr_le16(idVendor, "%04x\n");
723 usb_descriptor_attr_le16(idProduct, "%04x\n");
724 usb_descriptor_attr_le16(bcdDevice, "%04x\n");
725 
726 #define usb_descriptor_attr(field, format_string)			\
727 static ssize_t								\
728 field##_show(struct device *dev, struct device_attribute *attr,	\
729 		char *buf)						\
730 {									\
731 	struct usb_device *udev;					\
732 									\
733 	udev = to_usb_device(dev);					\
734 	return sprintf(buf, format_string, udev->descriptor.field);	\
735 }									\
736 static DEVICE_ATTR_RO(field)
737 
738 usb_descriptor_attr(bDeviceClass, "%02x\n");
739 usb_descriptor_attr(bDeviceSubClass, "%02x\n");
740 usb_descriptor_attr(bDeviceProtocol, "%02x\n");
741 usb_descriptor_attr(bNumConfigurations, "%d\n");
742 usb_descriptor_attr(bMaxPacketSize0, "%d\n");
743 
744 
745 /* show if the device is authorized (1) or not (0) */
746 static ssize_t authorized_show(struct device *dev,
747 			       struct device_attribute *attr, char *buf)
748 {
749 	struct usb_device *usb_dev = to_usb_device(dev);
750 	return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
751 }
752 
753 /*
754  * Authorize a device to be used in the system
755  *
756  * Writing a 0 deauthorizes the device, writing a 1 authorizes it.
757  */
758 static ssize_t authorized_store(struct device *dev,
759 				struct device_attribute *attr, const char *buf,
760 				size_t size)
761 {
762 	ssize_t result;
763 	struct usb_device *usb_dev = to_usb_device(dev);
764 	unsigned val;
765 	result = sscanf(buf, "%u\n", &val);
766 	if (result != 1)
767 		result = -EINVAL;
768 	else if (val == 0)
769 		result = usb_deauthorize_device(usb_dev);
770 	else
771 		result = usb_authorize_device(usb_dev);
772 	return result < 0 ? result : size;
773 }
774 static DEVICE_ATTR_IGNORE_LOCKDEP(authorized, S_IRUGO | S_IWUSR,
775 				  authorized_show, authorized_store);
776 
777 /* "Safely remove a device" */
778 static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
779 			    const char *buf, size_t count)
780 {
781 	struct usb_device *udev = to_usb_device(dev);
782 	int rc = 0;
783 
784 	usb_lock_device(udev);
785 	if (udev->state != USB_STATE_NOTATTACHED) {
786 
787 		/* To avoid races, first unconfigure and then remove */
788 		usb_set_configuration(udev, -1);
789 		rc = usb_remove_device(udev);
790 	}
791 	if (rc == 0)
792 		rc = count;
793 	usb_unlock_device(udev);
794 	return rc;
795 }
796 static DEVICE_ATTR_IGNORE_LOCKDEP(remove, S_IWUSR, NULL, remove_store);
797 
798 
799 static struct attribute *dev_attrs[] = {
800 	/* current configuration's attributes */
801 	&dev_attr_configuration.attr,
802 	&dev_attr_bNumInterfaces.attr,
803 	&dev_attr_bConfigurationValue.attr,
804 	&dev_attr_bmAttributes.attr,
805 	&dev_attr_bMaxPower.attr,
806 	/* device attributes */
807 	&dev_attr_urbnum.attr,
808 	&dev_attr_idVendor.attr,
809 	&dev_attr_idProduct.attr,
810 	&dev_attr_bcdDevice.attr,
811 	&dev_attr_bDeviceClass.attr,
812 	&dev_attr_bDeviceSubClass.attr,
813 	&dev_attr_bDeviceProtocol.attr,
814 	&dev_attr_bNumConfigurations.attr,
815 	&dev_attr_bMaxPacketSize0.attr,
816 	&dev_attr_speed.attr,
817 	&dev_attr_rx_lanes.attr,
818 	&dev_attr_tx_lanes.attr,
819 	&dev_attr_busnum.attr,
820 	&dev_attr_devnum.attr,
821 	&dev_attr_devpath.attr,
822 	&dev_attr_version.attr,
823 	&dev_attr_maxchild.attr,
824 	&dev_attr_quirks.attr,
825 	&dev_attr_avoid_reset_quirk.attr,
826 	&dev_attr_authorized.attr,
827 	&dev_attr_remove.attr,
828 	&dev_attr_removable.attr,
829 	&dev_attr_ltm_capable.attr,
830 #ifdef CONFIG_OF
831 	&dev_attr_devspec.attr,
832 #endif
833 	NULL,
834 };
835 static struct attribute_group dev_attr_grp = {
836 	.attrs = dev_attrs,
837 };
838 
839 /* When modifying this list, be sure to modify dev_string_attrs_are_visible()
840  * accordingly.
841  */
842 static struct attribute *dev_string_attrs[] = {
843 	&dev_attr_manufacturer.attr,
844 	&dev_attr_product.attr,
845 	&dev_attr_serial.attr,
846 	NULL
847 };
848 
849 static umode_t dev_string_attrs_are_visible(struct kobject *kobj,
850 		struct attribute *a, int n)
851 {
852 	struct device *dev = kobj_to_dev(kobj);
853 	struct usb_device *udev = to_usb_device(dev);
854 
855 	if (a == &dev_attr_manufacturer.attr) {
856 		if (udev->manufacturer == NULL)
857 			return 0;
858 	} else if (a == &dev_attr_product.attr) {
859 		if (udev->product == NULL)
860 			return 0;
861 	} else if (a == &dev_attr_serial.attr) {
862 		if (udev->serial == NULL)
863 			return 0;
864 	}
865 	return a->mode;
866 }
867 
868 static struct attribute_group dev_string_attr_grp = {
869 	.attrs =	dev_string_attrs,
870 	.is_visible =	dev_string_attrs_are_visible,
871 };
872 
873 const struct attribute_group *usb_device_groups[] = {
874 	&dev_attr_grp,
875 	&dev_string_attr_grp,
876 	NULL
877 };
878 
879 /* Binary descriptors */
880 
881 static ssize_t
882 read_descriptors(struct file *filp, struct kobject *kobj,
883 		struct bin_attribute *attr,
884 		char *buf, loff_t off, size_t count)
885 {
886 	struct device *dev = kobj_to_dev(kobj);
887 	struct usb_device *udev = to_usb_device(dev);
888 	size_t nleft = count;
889 	size_t srclen, n;
890 	int cfgno;
891 	void *src;
892 
893 	/* The binary attribute begins with the device descriptor.
894 	 * Following that are the raw descriptor entries for all the
895 	 * configurations (config plus subsidiary descriptors).
896 	 */
897 	for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
898 			nleft > 0; ++cfgno) {
899 		if (cfgno < 0) {
900 			src = &udev->descriptor;
901 			srclen = sizeof(struct usb_device_descriptor);
902 		} else {
903 			src = udev->rawdescriptors[cfgno];
904 			srclen = __le16_to_cpu(udev->config[cfgno].desc.
905 					wTotalLength);
906 		}
907 		if (off < srclen) {
908 			n = min(nleft, srclen - (size_t) off);
909 			memcpy(buf, src + off, n);
910 			nleft -= n;
911 			buf += n;
912 			off = 0;
913 		} else {
914 			off -= srclen;
915 		}
916 	}
917 	return count - nleft;
918 }
919 
920 static struct bin_attribute dev_bin_attr_descriptors = {
921 	.attr = {.name = "descriptors", .mode = 0444},
922 	.read = read_descriptors,
923 	.size = 18 + 65535,	/* dev descr + max-size raw descriptor */
924 };
925 
926 /*
927  * Show & store the current value of authorized_default
928  */
929 static ssize_t authorized_default_show(struct device *dev,
930 				       struct device_attribute *attr, char *buf)
931 {
932 	struct usb_device *rh_usb_dev = to_usb_device(dev);
933 	struct usb_bus *usb_bus = rh_usb_dev->bus;
934 	struct usb_hcd *hcd;
935 
936 	hcd = bus_to_hcd(usb_bus);
937 	return snprintf(buf, PAGE_SIZE, "%u\n", hcd->dev_policy);
938 }
939 
940 static ssize_t authorized_default_store(struct device *dev,
941 					struct device_attribute *attr,
942 					const char *buf, size_t size)
943 {
944 	ssize_t result;
945 	unsigned int val;
946 	struct usb_device *rh_usb_dev = to_usb_device(dev);
947 	struct usb_bus *usb_bus = rh_usb_dev->bus;
948 	struct usb_hcd *hcd;
949 
950 	hcd = bus_to_hcd(usb_bus);
951 	result = sscanf(buf, "%u\n", &val);
952 	if (result == 1) {
953 		hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ?
954 			val : USB_DEVICE_AUTHORIZE_ALL;
955 		result = size;
956 	} else {
957 		result = -EINVAL;
958 	}
959 	return result;
960 }
961 static DEVICE_ATTR_RW(authorized_default);
962 
963 /*
964  * interface_authorized_default_show - show default authorization status
965  * for USB interfaces
966  *
967  * note: interface_authorized_default is the default value
968  *       for initializing the authorized attribute of interfaces
969  */
970 static ssize_t interface_authorized_default_show(struct device *dev,
971 		struct device_attribute *attr, char *buf)
972 {
973 	struct usb_device *usb_dev = to_usb_device(dev);
974 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
975 
976 	return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
977 }
978 
979 /*
980  * interface_authorized_default_store - store default authorization status
981  * for USB interfaces
982  *
983  * note: interface_authorized_default is the default value
984  *       for initializing the authorized attribute of interfaces
985  */
986 static ssize_t interface_authorized_default_store(struct device *dev,
987 		struct device_attribute *attr, const char *buf, size_t count)
988 {
989 	struct usb_device *usb_dev = to_usb_device(dev);
990 	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
991 	int rc = count;
992 	bool val;
993 
994 	if (strtobool(buf, &val) != 0)
995 		return -EINVAL;
996 
997 	if (val)
998 		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
999 	else
1000 		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
1001 
1002 	return rc;
1003 }
1004 static DEVICE_ATTR_RW(interface_authorized_default);
1005 
1006 /* Group all the USB bus attributes */
1007 static struct attribute *usb_bus_attrs[] = {
1008 		&dev_attr_authorized_default.attr,
1009 		&dev_attr_interface_authorized_default.attr,
1010 		NULL,
1011 };
1012 
1013 static const struct attribute_group usb_bus_attr_group = {
1014 	.name = NULL,	/* we want them in the same directory */
1015 	.attrs = usb_bus_attrs,
1016 };
1017 
1018 
1019 static int add_default_authorized_attributes(struct device *dev)
1020 {
1021 	int rc = 0;
1022 
1023 	if (is_usb_device(dev))
1024 		rc = sysfs_create_group(&dev->kobj, &usb_bus_attr_group);
1025 
1026 	return rc;
1027 }
1028 
1029 static void remove_default_authorized_attributes(struct device *dev)
1030 {
1031 	if (is_usb_device(dev)) {
1032 		sysfs_remove_group(&dev->kobj, &usb_bus_attr_group);
1033 	}
1034 }
1035 
1036 int usb_create_sysfs_dev_files(struct usb_device *udev)
1037 {
1038 	struct device *dev = &udev->dev;
1039 	int retval;
1040 
1041 	retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
1042 	if (retval)
1043 		goto error;
1044 
1045 	retval = add_persist_attributes(dev);
1046 	if (retval)
1047 		goto error;
1048 
1049 	retval = add_power_attributes(dev);
1050 	if (retval)
1051 		goto error;
1052 
1053 	if (is_root_hub(udev)) {
1054 		retval = add_default_authorized_attributes(dev);
1055 		if (retval)
1056 			goto error;
1057 	}
1058 	return retval;
1059 
1060 error:
1061 	usb_remove_sysfs_dev_files(udev);
1062 	return retval;
1063 }
1064 
1065 void usb_remove_sysfs_dev_files(struct usb_device *udev)
1066 {
1067 	struct device *dev = &udev->dev;
1068 
1069 	if (is_root_hub(udev))
1070 		remove_default_authorized_attributes(dev);
1071 
1072 	remove_power_attributes(dev);
1073 	remove_persist_attributes(dev);
1074 	device_remove_bin_file(dev, &dev_bin_attr_descriptors);
1075 }
1076 
1077 /* Interface Association Descriptor fields */
1078 #define usb_intf_assoc_attr(field, format_string)			\
1079 static ssize_t								\
1080 iad_##field##_show(struct device *dev, struct device_attribute *attr,	\
1081 		char *buf)						\
1082 {									\
1083 	struct usb_interface *intf = to_usb_interface(dev);		\
1084 									\
1085 	return sprintf(buf, format_string,				\
1086 			intf->intf_assoc->field); 			\
1087 }									\
1088 static DEVICE_ATTR_RO(iad_##field)
1089 
1090 usb_intf_assoc_attr(bFirstInterface, "%02x\n");
1091 usb_intf_assoc_attr(bInterfaceCount, "%02d\n");
1092 usb_intf_assoc_attr(bFunctionClass, "%02x\n");
1093 usb_intf_assoc_attr(bFunctionSubClass, "%02x\n");
1094 usb_intf_assoc_attr(bFunctionProtocol, "%02x\n");
1095 
1096 /* Interface fields */
1097 #define usb_intf_attr(field, format_string)				\
1098 static ssize_t								\
1099 field##_show(struct device *dev, struct device_attribute *attr,		\
1100 		char *buf)						\
1101 {									\
1102 	struct usb_interface *intf = to_usb_interface(dev);		\
1103 									\
1104 	return sprintf(buf, format_string,				\
1105 			intf->cur_altsetting->desc.field); 		\
1106 }									\
1107 static DEVICE_ATTR_RO(field)
1108 
1109 usb_intf_attr(bInterfaceNumber, "%02x\n");
1110 usb_intf_attr(bAlternateSetting, "%2d\n");
1111 usb_intf_attr(bNumEndpoints, "%02x\n");
1112 usb_intf_attr(bInterfaceClass, "%02x\n");
1113 usb_intf_attr(bInterfaceSubClass, "%02x\n");
1114 usb_intf_attr(bInterfaceProtocol, "%02x\n");
1115 
1116 static ssize_t interface_show(struct device *dev, struct device_attribute *attr,
1117 			      char *buf)
1118 {
1119 	struct usb_interface *intf;
1120 	char *string;
1121 
1122 	intf = to_usb_interface(dev);
1123 	string = READ_ONCE(intf->cur_altsetting->string);
1124 	if (!string)
1125 		return 0;
1126 	return sprintf(buf, "%s\n", string);
1127 }
1128 static DEVICE_ATTR_RO(interface);
1129 
1130 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
1131 			     char *buf)
1132 {
1133 	struct usb_interface *intf;
1134 	struct usb_device *udev;
1135 	struct usb_host_interface *alt;
1136 
1137 	intf = to_usb_interface(dev);
1138 	udev = interface_to_usbdev(intf);
1139 	alt = READ_ONCE(intf->cur_altsetting);
1140 
1141 	return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
1142 			"ic%02Xisc%02Xip%02Xin%02X\n",
1143 			le16_to_cpu(udev->descriptor.idVendor),
1144 			le16_to_cpu(udev->descriptor.idProduct),
1145 			le16_to_cpu(udev->descriptor.bcdDevice),
1146 			udev->descriptor.bDeviceClass,
1147 			udev->descriptor.bDeviceSubClass,
1148 			udev->descriptor.bDeviceProtocol,
1149 			alt->desc.bInterfaceClass,
1150 			alt->desc.bInterfaceSubClass,
1151 			alt->desc.bInterfaceProtocol,
1152 			alt->desc.bInterfaceNumber);
1153 }
1154 static DEVICE_ATTR_RO(modalias);
1155 
1156 static ssize_t supports_autosuspend_show(struct device *dev,
1157 					 struct device_attribute *attr,
1158 					 char *buf)
1159 {
1160 	int s;
1161 
1162 	s = device_lock_interruptible(dev);
1163 	if (s < 0)
1164 		return -EINTR;
1165 	/* Devices will be autosuspended even when an interface isn't claimed */
1166 	s = (!dev->driver || to_usb_driver(dev->driver)->supports_autosuspend);
1167 	device_unlock(dev);
1168 
1169 	return sprintf(buf, "%u\n", s);
1170 }
1171 static DEVICE_ATTR_RO(supports_autosuspend);
1172 
1173 /*
1174  * interface_authorized_show - show authorization status of an USB interface
1175  * 1 is authorized, 0 is deauthorized
1176  */
1177 static ssize_t interface_authorized_show(struct device *dev,
1178 		struct device_attribute *attr, char *buf)
1179 {
1180 	struct usb_interface *intf = to_usb_interface(dev);
1181 
1182 	return sprintf(buf, "%u\n", intf->authorized);
1183 }
1184 
1185 /*
1186  * interface_authorized_store - authorize or deauthorize an USB interface
1187  */
1188 static ssize_t interface_authorized_store(struct device *dev,
1189 		struct device_attribute *attr, const char *buf, size_t count)
1190 {
1191 	struct usb_interface *intf = to_usb_interface(dev);
1192 	bool val;
1193 
1194 	if (strtobool(buf, &val) != 0)
1195 		return -EINVAL;
1196 
1197 	if (val)
1198 		usb_authorize_interface(intf);
1199 	else
1200 		usb_deauthorize_interface(intf);
1201 
1202 	return count;
1203 }
1204 static struct device_attribute dev_attr_interface_authorized =
1205 		__ATTR(authorized, S_IRUGO | S_IWUSR,
1206 		interface_authorized_show, interface_authorized_store);
1207 
1208 static struct attribute *intf_attrs[] = {
1209 	&dev_attr_bInterfaceNumber.attr,
1210 	&dev_attr_bAlternateSetting.attr,
1211 	&dev_attr_bNumEndpoints.attr,
1212 	&dev_attr_bInterfaceClass.attr,
1213 	&dev_attr_bInterfaceSubClass.attr,
1214 	&dev_attr_bInterfaceProtocol.attr,
1215 	&dev_attr_modalias.attr,
1216 	&dev_attr_supports_autosuspend.attr,
1217 	&dev_attr_interface_authorized.attr,
1218 	NULL,
1219 };
1220 static struct attribute_group intf_attr_grp = {
1221 	.attrs = intf_attrs,
1222 };
1223 
1224 static struct attribute *intf_assoc_attrs[] = {
1225 	&dev_attr_iad_bFirstInterface.attr,
1226 	&dev_attr_iad_bInterfaceCount.attr,
1227 	&dev_attr_iad_bFunctionClass.attr,
1228 	&dev_attr_iad_bFunctionSubClass.attr,
1229 	&dev_attr_iad_bFunctionProtocol.attr,
1230 	NULL,
1231 };
1232 
1233 static umode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
1234 		struct attribute *a, int n)
1235 {
1236 	struct device *dev = kobj_to_dev(kobj);
1237 	struct usb_interface *intf = to_usb_interface(dev);
1238 
1239 	if (intf->intf_assoc == NULL)
1240 		return 0;
1241 	return a->mode;
1242 }
1243 
1244 static struct attribute_group intf_assoc_attr_grp = {
1245 	.attrs =	intf_assoc_attrs,
1246 	.is_visible =	intf_assoc_attrs_are_visible,
1247 };
1248 
1249 const struct attribute_group *usb_interface_groups[] = {
1250 	&intf_attr_grp,
1251 	&intf_assoc_attr_grp,
1252 	NULL
1253 };
1254 
1255 void usb_create_sysfs_intf_files(struct usb_interface *intf)
1256 {
1257 	struct usb_device *udev = interface_to_usbdev(intf);
1258 	struct usb_host_interface *alt = intf->cur_altsetting;
1259 
1260 	if (intf->sysfs_files_created || intf->unregistering)
1261 		return;
1262 
1263 	if (!alt->string && !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
1264 		alt->string = usb_cache_string(udev, alt->desc.iInterface);
1265 	if (alt->string && device_create_file(&intf->dev, &dev_attr_interface)) {
1266 		/* This is not a serious error */
1267 		dev_dbg(&intf->dev, "interface string descriptor file not created\n");
1268 	}
1269 	intf->sysfs_files_created = 1;
1270 }
1271 
1272 void usb_remove_sysfs_intf_files(struct usb_interface *intf)
1273 {
1274 	if (!intf->sysfs_files_created)
1275 		return;
1276 
1277 	device_remove_file(&intf->dev, &dev_attr_interface);
1278 	intf->sysfs_files_created = 0;
1279 }
1280