xref: /linux/drivers/base/power/sysfs.c (revision 95298d63c67673c654c08952672d016212b26054)
1 // SPDX-License-Identifier: GPL-2.0
2 /* sysfs entries for device PM */
3 #include <linux/device.h>
4 #include <linux/string.h>
5 #include <linux/export.h>
6 #include <linux/pm_qos.h>
7 #include <linux/pm_runtime.h>
8 #include <linux/pm_wakeup.h>
9 #include <linux/atomic.h>
10 #include <linux/jiffies.h>
11 #include "power.h"
12 
13 /*
14  *	control - Report/change current runtime PM setting of the device
15  *
16  *	Runtime power management of a device can be blocked with the help of
17  *	this attribute.  All devices have one of the following two values for
18  *	the power/control file:
19  *
20  *	 + "auto\n" to allow the device to be power managed at run time;
21  *	 + "on\n" to prevent the device from being power managed at run time;
22  *
23  *	The default for all devices is "auto", which means that devices may be
24  *	subject to automatic power management, depending on their drivers.
25  *	Changing this attribute to "on" prevents the driver from power managing
26  *	the device at run time.  Doing that while the device is suspended causes
27  *	it to be woken up.
28  *
29  *	wakeup - Report/change current wakeup option for device
30  *
31  *	Some devices support "wakeup" events, which are hardware signals
32  *	used to activate devices from suspended or low power states.  Such
33  *	devices have one of three values for the sysfs power/wakeup file:
34  *
35  *	 + "enabled\n" to issue the events;
36  *	 + "disabled\n" not to do so; or
37  *	 + "\n" for temporary or permanent inability to issue wakeup.
38  *
39  *	(For example, unconfigured USB devices can't issue wakeups.)
40  *
41  *	Familiar examples of devices that can issue wakeup events include
42  *	keyboards and mice (both PS2 and USB styles), power buttons, modems,
43  *	"Wake-On-LAN" Ethernet links, GPIO lines, and more.  Some events
44  *	will wake the entire system from a suspend state; others may just
45  *	wake up the device (if the system as a whole is already active).
46  *	Some wakeup events use normal IRQ lines; other use special out
47  *	of band signaling.
48  *
49  *	It is the responsibility of device drivers to enable (or disable)
50  *	wakeup signaling as part of changing device power states, respecting
51  *	the policy choices provided through the driver model.
52  *
53  *	Devices may not be able to generate wakeup events from all power
54  *	states.  Also, the events may be ignored in some configurations;
55  *	for example, they might need help from other devices that aren't
56  *	active, or which may have wakeup disabled.  Some drivers rely on
57  *	wakeup events internally (unless they are disabled), keeping
58  *	their hardware in low power modes whenever they're unused.  This
59  *	saves runtime power, without requiring system-wide sleep states.
60  *
61  *	async - Report/change current async suspend setting for the device
62  *
63  *	Asynchronous suspend and resume of the device during system-wide power
64  *	state transitions can be enabled by writing "enabled" to this file.
65  *	Analogously, if "disabled" is written to this file, the device will be
66  *	suspended and resumed synchronously.
67  *
68  *	All devices have one of the following two values for power/async:
69  *
70  *	 + "enabled\n" to permit the asynchronous suspend/resume of the device;
71  *	 + "disabled\n" to forbid it;
72  *
73  *	NOTE: It generally is unsafe to permit the asynchronous suspend/resume
74  *	of a device unless it is certain that all of the PM dependencies of the
75  *	device are known to the PM core.  However, for some devices this
76  *	attribute is set to "enabled" by bus type code or device drivers and in
77  *	that cases it should be safe to leave the default value.
78  *
79  *	autosuspend_delay_ms - Report/change a device's autosuspend_delay value
80  *
81  *	Some drivers don't want to carry out a runtime suspend as soon as a
82  *	device becomes idle; they want it always to remain idle for some period
83  *	of time before suspending it.  This period is the autosuspend_delay
84  *	value (expressed in milliseconds) and it can be controlled by the user.
85  *	If the value is negative then the device will never be runtime
86  *	suspended.
87  *
88  *	NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
89  *	value are used only if the driver calls pm_runtime_use_autosuspend().
90  *
91  *	wakeup_count - Report the number of wakeup events related to the device
92  */
93 
94 const char power_group_name[] = "power";
95 EXPORT_SYMBOL_GPL(power_group_name);
96 
97 static const char ctrl_auto[] = "auto";
98 static const char ctrl_on[] = "on";
99 
100 static ssize_t control_show(struct device *dev, struct device_attribute *attr,
101 			    char *buf)
102 {
103 	return sprintf(buf, "%s\n",
104 				dev->power.runtime_auto ? ctrl_auto : ctrl_on);
105 }
106 
107 static ssize_t control_store(struct device * dev, struct device_attribute *attr,
108 			     const char * buf, size_t n)
109 {
110 	device_lock(dev);
111 	if (sysfs_streq(buf, ctrl_auto))
112 		pm_runtime_allow(dev);
113 	else if (sysfs_streq(buf, ctrl_on))
114 		pm_runtime_forbid(dev);
115 	else
116 		n = -EINVAL;
117 	device_unlock(dev);
118 	return n;
119 }
120 
121 static DEVICE_ATTR_RW(control);
122 
123 static ssize_t runtime_active_time_show(struct device *dev,
124 				struct device_attribute *attr, char *buf)
125 {
126 	int ret;
127 	u64 tmp = pm_runtime_active_time(dev);
128 	do_div(tmp, NSEC_PER_MSEC);
129 	ret = sprintf(buf, "%llu\n", tmp);
130 	return ret;
131 }
132 
133 static DEVICE_ATTR_RO(runtime_active_time);
134 
135 static ssize_t runtime_suspended_time_show(struct device *dev,
136 				struct device_attribute *attr, char *buf)
137 {
138 	int ret;
139 	u64 tmp = pm_runtime_suspended_time(dev);
140 	do_div(tmp, NSEC_PER_MSEC);
141 	ret = sprintf(buf, "%llu\n", tmp);
142 	return ret;
143 }
144 
145 static DEVICE_ATTR_RO(runtime_suspended_time);
146 
147 static ssize_t runtime_status_show(struct device *dev,
148 				struct device_attribute *attr, char *buf)
149 {
150 	const char *p;
151 
152 	if (dev->power.runtime_error) {
153 		p = "error\n";
154 	} else if (dev->power.disable_depth) {
155 		p = "unsupported\n";
156 	} else {
157 		switch (dev->power.runtime_status) {
158 		case RPM_SUSPENDED:
159 			p = "suspended\n";
160 			break;
161 		case RPM_SUSPENDING:
162 			p = "suspending\n";
163 			break;
164 		case RPM_RESUMING:
165 			p = "resuming\n";
166 			break;
167 		case RPM_ACTIVE:
168 			p = "active\n";
169 			break;
170 		default:
171 			return -EIO;
172 		}
173 	}
174 	return sprintf(buf, p);
175 }
176 
177 static DEVICE_ATTR_RO(runtime_status);
178 
179 static ssize_t autosuspend_delay_ms_show(struct device *dev,
180 		struct device_attribute *attr, char *buf)
181 {
182 	if (!dev->power.use_autosuspend)
183 		return -EIO;
184 	return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
185 }
186 
187 static ssize_t autosuspend_delay_ms_store(struct device *dev,
188 		struct device_attribute *attr, const char *buf, size_t n)
189 {
190 	long delay;
191 
192 	if (!dev->power.use_autosuspend)
193 		return -EIO;
194 
195 	if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay)
196 		return -EINVAL;
197 
198 	device_lock(dev);
199 	pm_runtime_set_autosuspend_delay(dev, delay);
200 	device_unlock(dev);
201 	return n;
202 }
203 
204 static DEVICE_ATTR_RW(autosuspend_delay_ms);
205 
206 static ssize_t pm_qos_resume_latency_us_show(struct device *dev,
207 					     struct device_attribute *attr,
208 					     char *buf)
209 {
210 	s32 value = dev_pm_qos_requested_resume_latency(dev);
211 
212 	if (value == 0)
213 		return sprintf(buf, "n/a\n");
214 	if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
215 		value = 0;
216 
217 	return sprintf(buf, "%d\n", value);
218 }
219 
220 static ssize_t pm_qos_resume_latency_us_store(struct device *dev,
221 					      struct device_attribute *attr,
222 					      const char *buf, size_t n)
223 {
224 	s32 value;
225 	int ret;
226 
227 	if (!kstrtos32(buf, 0, &value)) {
228 		/*
229 		 * Prevent users from writing negative or "no constraint" values
230 		 * directly.
231 		 */
232 		if (value < 0 || value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
233 			return -EINVAL;
234 
235 		if (value == 0)
236 			value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
237 	} else if (sysfs_streq(buf, "n/a")) {
238 		value = 0;
239 	} else {
240 		return -EINVAL;
241 	}
242 
243 	ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req,
244 					value);
245 	return ret < 0 ? ret : n;
246 }
247 
248 static DEVICE_ATTR_RW(pm_qos_resume_latency_us);
249 
250 static ssize_t pm_qos_latency_tolerance_us_show(struct device *dev,
251 						struct device_attribute *attr,
252 						char *buf)
253 {
254 	s32 value = dev_pm_qos_get_user_latency_tolerance(dev);
255 
256 	if (value < 0)
257 		return sprintf(buf, "auto\n");
258 	if (value == PM_QOS_LATENCY_ANY)
259 		return sprintf(buf, "any\n");
260 
261 	return sprintf(buf, "%d\n", value);
262 }
263 
264 static ssize_t pm_qos_latency_tolerance_us_store(struct device *dev,
265 						 struct device_attribute *attr,
266 						 const char *buf, size_t n)
267 {
268 	s32 value;
269 	int ret;
270 
271 	if (kstrtos32(buf, 0, &value) == 0) {
272 		/* Users can't write negative values directly */
273 		if (value < 0)
274 			return -EINVAL;
275 	} else {
276 		if (sysfs_streq(buf, "auto"))
277 			value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;
278 		else if (sysfs_streq(buf, "any"))
279 			value = PM_QOS_LATENCY_ANY;
280 		else
281 			return -EINVAL;
282 	}
283 	ret = dev_pm_qos_update_user_latency_tolerance(dev, value);
284 	return ret < 0 ? ret : n;
285 }
286 
287 static DEVICE_ATTR_RW(pm_qos_latency_tolerance_us);
288 
289 static ssize_t pm_qos_no_power_off_show(struct device *dev,
290 					struct device_attribute *attr,
291 					char *buf)
292 {
293 	return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
294 					& PM_QOS_FLAG_NO_POWER_OFF));
295 }
296 
297 static ssize_t pm_qos_no_power_off_store(struct device *dev,
298 					 struct device_attribute *attr,
299 					 const char *buf, size_t n)
300 {
301 	int ret;
302 
303 	if (kstrtoint(buf, 0, &ret))
304 		return -EINVAL;
305 
306 	if (ret != 0 && ret != 1)
307 		return -EINVAL;
308 
309 	ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret);
310 	return ret < 0 ? ret : n;
311 }
312 
313 static DEVICE_ATTR_RW(pm_qos_no_power_off);
314 
315 #ifdef CONFIG_PM_SLEEP
316 static const char _enabled[] = "enabled";
317 static const char _disabled[] = "disabled";
318 
319 static ssize_t wakeup_show(struct device *dev, struct device_attribute *attr,
320 			   char *buf)
321 {
322 	return sprintf(buf, "%s\n", device_can_wakeup(dev)
323 		? (device_may_wakeup(dev) ? _enabled : _disabled)
324 		: "");
325 }
326 
327 static ssize_t wakeup_store(struct device *dev, struct device_attribute *attr,
328 			    const char *buf, size_t n)
329 {
330 	if (!device_can_wakeup(dev))
331 		return -EINVAL;
332 
333 	if (sysfs_streq(buf, _enabled))
334 		device_set_wakeup_enable(dev, 1);
335 	else if (sysfs_streq(buf, _disabled))
336 		device_set_wakeup_enable(dev, 0);
337 	else
338 		return -EINVAL;
339 	return n;
340 }
341 
342 static DEVICE_ATTR_RW(wakeup);
343 
344 static ssize_t wakeup_count_show(struct device *dev,
345 				 struct device_attribute *attr, char *buf)
346 {
347 	unsigned long count = 0;
348 	bool enabled = false;
349 
350 	spin_lock_irq(&dev->power.lock);
351 	if (dev->power.wakeup) {
352 		count = dev->power.wakeup->wakeup_count;
353 		enabled = true;
354 	}
355 	spin_unlock_irq(&dev->power.lock);
356 	return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
357 }
358 
359 static DEVICE_ATTR_RO(wakeup_count);
360 
361 static ssize_t wakeup_active_count_show(struct device *dev,
362 					struct device_attribute *attr,
363 					char *buf)
364 {
365 	unsigned long count = 0;
366 	bool enabled = false;
367 
368 	spin_lock_irq(&dev->power.lock);
369 	if (dev->power.wakeup) {
370 		count = dev->power.wakeup->active_count;
371 		enabled = true;
372 	}
373 	spin_unlock_irq(&dev->power.lock);
374 	return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
375 }
376 
377 static DEVICE_ATTR_RO(wakeup_active_count);
378 
379 static ssize_t wakeup_abort_count_show(struct device *dev,
380 				       struct device_attribute *attr,
381 				       char *buf)
382 {
383 	unsigned long count = 0;
384 	bool enabled = false;
385 
386 	spin_lock_irq(&dev->power.lock);
387 	if (dev->power.wakeup) {
388 		count = dev->power.wakeup->wakeup_count;
389 		enabled = true;
390 	}
391 	spin_unlock_irq(&dev->power.lock);
392 	return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
393 }
394 
395 static DEVICE_ATTR_RO(wakeup_abort_count);
396 
397 static ssize_t wakeup_expire_count_show(struct device *dev,
398 					struct device_attribute *attr,
399 					char *buf)
400 {
401 	unsigned long count = 0;
402 	bool enabled = false;
403 
404 	spin_lock_irq(&dev->power.lock);
405 	if (dev->power.wakeup) {
406 		count = dev->power.wakeup->expire_count;
407 		enabled = true;
408 	}
409 	spin_unlock_irq(&dev->power.lock);
410 	return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
411 }
412 
413 static DEVICE_ATTR_RO(wakeup_expire_count);
414 
415 static ssize_t wakeup_active_show(struct device *dev,
416 				  struct device_attribute *attr, char *buf)
417 {
418 	unsigned int active = 0;
419 	bool enabled = false;
420 
421 	spin_lock_irq(&dev->power.lock);
422 	if (dev->power.wakeup) {
423 		active = dev->power.wakeup->active;
424 		enabled = true;
425 	}
426 	spin_unlock_irq(&dev->power.lock);
427 	return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
428 }
429 
430 static DEVICE_ATTR_RO(wakeup_active);
431 
432 static ssize_t wakeup_total_time_ms_show(struct device *dev,
433 					 struct device_attribute *attr,
434 					 char *buf)
435 {
436 	s64 msec = 0;
437 	bool enabled = false;
438 
439 	spin_lock_irq(&dev->power.lock);
440 	if (dev->power.wakeup) {
441 		msec = ktime_to_ms(dev->power.wakeup->total_time);
442 		enabled = true;
443 	}
444 	spin_unlock_irq(&dev->power.lock);
445 	return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
446 }
447 
448 static DEVICE_ATTR_RO(wakeup_total_time_ms);
449 
450 static ssize_t wakeup_max_time_ms_show(struct device *dev,
451 				       struct device_attribute *attr, char *buf)
452 {
453 	s64 msec = 0;
454 	bool enabled = false;
455 
456 	spin_lock_irq(&dev->power.lock);
457 	if (dev->power.wakeup) {
458 		msec = ktime_to_ms(dev->power.wakeup->max_time);
459 		enabled = true;
460 	}
461 	spin_unlock_irq(&dev->power.lock);
462 	return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
463 }
464 
465 static DEVICE_ATTR_RO(wakeup_max_time_ms);
466 
467 static ssize_t wakeup_last_time_ms_show(struct device *dev,
468 					struct device_attribute *attr,
469 					char *buf)
470 {
471 	s64 msec = 0;
472 	bool enabled = false;
473 
474 	spin_lock_irq(&dev->power.lock);
475 	if (dev->power.wakeup) {
476 		msec = ktime_to_ms(dev->power.wakeup->last_time);
477 		enabled = true;
478 	}
479 	spin_unlock_irq(&dev->power.lock);
480 	return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
481 }
482 
483 static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid,
484 						kgid_t kgid)
485 {
486 	if (dev->power.wakeup && dev->power.wakeup->dev)
487 		return device_change_owner(dev->power.wakeup->dev, kuid, kgid);
488 	return 0;
489 }
490 
491 static DEVICE_ATTR_RO(wakeup_last_time_ms);
492 
493 #ifdef CONFIG_PM_AUTOSLEEP
494 static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev,
495 						 struct device_attribute *attr,
496 						 char *buf)
497 {
498 	s64 msec = 0;
499 	bool enabled = false;
500 
501 	spin_lock_irq(&dev->power.lock);
502 	if (dev->power.wakeup) {
503 		msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
504 		enabled = true;
505 	}
506 	spin_unlock_irq(&dev->power.lock);
507 	return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
508 }
509 
510 static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms);
511 #endif /* CONFIG_PM_AUTOSLEEP */
512 #else /* CONFIG_PM_SLEEP */
513 static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid,
514 						kgid_t kgid)
515 {
516 	return 0;
517 }
518 #endif
519 
520 #ifdef CONFIG_PM_ADVANCED_DEBUG
521 static ssize_t runtime_usage_show(struct device *dev,
522 				  struct device_attribute *attr, char *buf)
523 {
524 	return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
525 }
526 static DEVICE_ATTR_RO(runtime_usage);
527 
528 static ssize_t runtime_active_kids_show(struct device *dev,
529 					struct device_attribute *attr,
530 					char *buf)
531 {
532 	return sprintf(buf, "%d\n", dev->power.ignore_children ?
533 		0 : atomic_read(&dev->power.child_count));
534 }
535 static DEVICE_ATTR_RO(runtime_active_kids);
536 
537 static ssize_t runtime_enabled_show(struct device *dev,
538 				    struct device_attribute *attr, char *buf)
539 {
540 	if (dev->power.disable_depth && (dev->power.runtime_auto == false))
541 		return sprintf(buf, "disabled & forbidden\n");
542 	if (dev->power.disable_depth)
543 		return sprintf(buf, "disabled\n");
544 	if (dev->power.runtime_auto == false)
545 		return sprintf(buf, "forbidden\n");
546 	return sprintf(buf, "enabled\n");
547 }
548 static DEVICE_ATTR_RO(runtime_enabled);
549 
550 #ifdef CONFIG_PM_SLEEP
551 static ssize_t async_show(struct device *dev, struct device_attribute *attr,
552 			  char *buf)
553 {
554 	return sprintf(buf, "%s\n",
555 			device_async_suspend_enabled(dev) ?
556 				_enabled : _disabled);
557 }
558 
559 static ssize_t async_store(struct device *dev, struct device_attribute *attr,
560 			   const char *buf, size_t n)
561 {
562 	if (sysfs_streq(buf, _enabled))
563 		device_enable_async_suspend(dev);
564 	else if (sysfs_streq(buf, _disabled))
565 		device_disable_async_suspend(dev);
566 	else
567 		return -EINVAL;
568 	return n;
569 }
570 
571 static DEVICE_ATTR_RW(async);
572 
573 #endif /* CONFIG_PM_SLEEP */
574 #endif /* CONFIG_PM_ADVANCED_DEBUG */
575 
576 static struct attribute *power_attrs[] = {
577 #ifdef CONFIG_PM_ADVANCED_DEBUG
578 #ifdef CONFIG_PM_SLEEP
579 	&dev_attr_async.attr,
580 #endif
581 	&dev_attr_runtime_status.attr,
582 	&dev_attr_runtime_usage.attr,
583 	&dev_attr_runtime_active_kids.attr,
584 	&dev_attr_runtime_enabled.attr,
585 #endif /* CONFIG_PM_ADVANCED_DEBUG */
586 	NULL,
587 };
588 static const struct attribute_group pm_attr_group = {
589 	.name	= power_group_name,
590 	.attrs	= power_attrs,
591 };
592 
593 static struct attribute *wakeup_attrs[] = {
594 #ifdef CONFIG_PM_SLEEP
595 	&dev_attr_wakeup.attr,
596 	&dev_attr_wakeup_count.attr,
597 	&dev_attr_wakeup_active_count.attr,
598 	&dev_attr_wakeup_abort_count.attr,
599 	&dev_attr_wakeup_expire_count.attr,
600 	&dev_attr_wakeup_active.attr,
601 	&dev_attr_wakeup_total_time_ms.attr,
602 	&dev_attr_wakeup_max_time_ms.attr,
603 	&dev_attr_wakeup_last_time_ms.attr,
604 #ifdef CONFIG_PM_AUTOSLEEP
605 	&dev_attr_wakeup_prevent_sleep_time_ms.attr,
606 #endif
607 #endif
608 	NULL,
609 };
610 static const struct attribute_group pm_wakeup_attr_group = {
611 	.name	= power_group_name,
612 	.attrs	= wakeup_attrs,
613 };
614 
615 static struct attribute *runtime_attrs[] = {
616 #ifndef CONFIG_PM_ADVANCED_DEBUG
617 	&dev_attr_runtime_status.attr,
618 #endif
619 	&dev_attr_control.attr,
620 	&dev_attr_runtime_suspended_time.attr,
621 	&dev_attr_runtime_active_time.attr,
622 	&dev_attr_autosuspend_delay_ms.attr,
623 	NULL,
624 };
625 static const struct attribute_group pm_runtime_attr_group = {
626 	.name	= power_group_name,
627 	.attrs	= runtime_attrs,
628 };
629 
630 static struct attribute *pm_qos_resume_latency_attrs[] = {
631 	&dev_attr_pm_qos_resume_latency_us.attr,
632 	NULL,
633 };
634 static const struct attribute_group pm_qos_resume_latency_attr_group = {
635 	.name	= power_group_name,
636 	.attrs	= pm_qos_resume_latency_attrs,
637 };
638 
639 static struct attribute *pm_qos_latency_tolerance_attrs[] = {
640 	&dev_attr_pm_qos_latency_tolerance_us.attr,
641 	NULL,
642 };
643 static const struct attribute_group pm_qos_latency_tolerance_attr_group = {
644 	.name	= power_group_name,
645 	.attrs	= pm_qos_latency_tolerance_attrs,
646 };
647 
648 static struct attribute *pm_qos_flags_attrs[] = {
649 	&dev_attr_pm_qos_no_power_off.attr,
650 	NULL,
651 };
652 static const struct attribute_group pm_qos_flags_attr_group = {
653 	.name	= power_group_name,
654 	.attrs	= pm_qos_flags_attrs,
655 };
656 
657 int dpm_sysfs_add(struct device *dev)
658 {
659 	int rc;
660 
661 	/* No need to create PM sysfs if explicitly disabled. */
662 	if (device_pm_not_required(dev))
663 		return 0;
664 
665 	rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
666 	if (rc)
667 		return rc;
668 
669 	if (!pm_runtime_has_no_callbacks(dev)) {
670 		rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
671 		if (rc)
672 			goto err_out;
673 	}
674 	if (device_can_wakeup(dev)) {
675 		rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
676 		if (rc)
677 			goto err_runtime;
678 	}
679 	if (dev->power.set_latency_tolerance) {
680 		rc = sysfs_merge_group(&dev->kobj,
681 				       &pm_qos_latency_tolerance_attr_group);
682 		if (rc)
683 			goto err_wakeup;
684 	}
685 	rc = pm_wakeup_source_sysfs_add(dev);
686 	if (rc)
687 		goto err_latency;
688 	return 0;
689 
690  err_latency:
691 	sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
692  err_wakeup:
693 	sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
694  err_runtime:
695 	sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
696  err_out:
697 	sysfs_remove_group(&dev->kobj, &pm_attr_group);
698 	return rc;
699 }
700 
701 int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid)
702 {
703 	int rc;
704 
705 	if (device_pm_not_required(dev))
706 		return 0;
707 
708 	rc = sysfs_group_change_owner(&dev->kobj, &pm_attr_group, kuid, kgid);
709 	if (rc)
710 		return rc;
711 
712 	if (!pm_runtime_has_no_callbacks(dev)) {
713 		rc = sysfs_group_change_owner(
714 			&dev->kobj, &pm_runtime_attr_group, kuid, kgid);
715 		if (rc)
716 			return rc;
717 	}
718 
719 	if (device_can_wakeup(dev)) {
720 		rc = sysfs_group_change_owner(&dev->kobj, &pm_wakeup_attr_group,
721 					      kuid, kgid);
722 		if (rc)
723 			return rc;
724 
725 		rc = dpm_sysfs_wakeup_change_owner(dev, kuid, kgid);
726 		if (rc)
727 			return rc;
728 	}
729 
730 	if (dev->power.set_latency_tolerance) {
731 		rc = sysfs_group_change_owner(
732 			&dev->kobj, &pm_qos_latency_tolerance_attr_group, kuid,
733 			kgid);
734 		if (rc)
735 			return rc;
736 	}
737 	return 0;
738 }
739 
740 int wakeup_sysfs_add(struct device *dev)
741 {
742 	return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
743 }
744 
745 void wakeup_sysfs_remove(struct device *dev)
746 {
747 	sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
748 }
749 
750 int pm_qos_sysfs_add_resume_latency(struct device *dev)
751 {
752 	return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
753 }
754 
755 void pm_qos_sysfs_remove_resume_latency(struct device *dev)
756 {
757 	sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
758 }
759 
760 int pm_qos_sysfs_add_flags(struct device *dev)
761 {
762 	return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group);
763 }
764 
765 void pm_qos_sysfs_remove_flags(struct device *dev)
766 {
767 	sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
768 }
769 
770 int pm_qos_sysfs_add_latency_tolerance(struct device *dev)
771 {
772 	return sysfs_merge_group(&dev->kobj,
773 				 &pm_qos_latency_tolerance_attr_group);
774 }
775 
776 void pm_qos_sysfs_remove_latency_tolerance(struct device *dev)
777 {
778 	sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
779 }
780 
781 void rpm_sysfs_remove(struct device *dev)
782 {
783 	sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
784 }
785 
786 void dpm_sysfs_remove(struct device *dev)
787 {
788 	if (device_pm_not_required(dev))
789 		return;
790 	sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
791 	dev_pm_qos_constraints_destroy(dev);
792 	rpm_sysfs_remove(dev);
793 	sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
794 	sysfs_remove_group(&dev->kobj, &pm_attr_group);
795 }
796