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