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1// SPDX-License-Identifier: GPL-2.0
2/* sysfs entries for device PM */
3#include <linux/device.h>
4#include <linux/kobject.h>
5#include <linux/string.h>
6#include <linux/export.h>
7#include <linux/pm_qos.h>
8#include <linux/pm_runtime.h>
9#include <linux/pm_wakeup.h>
10#include <linux/atomic.h>
11#include <linux/jiffies.h>
12#include "power.h"
13
14/*
15 * control - Report/change current runtime PM setting of the device
16 *
17 * Runtime power management of a device can be blocked with the help of
18 * this attribute. All devices have one of the following two values for
19 * the power/control file:
20 *
21 * + "auto\n" to allow the device to be power managed at run time;
22 * + "on\n" to prevent the device from being power managed at run time;
23 *
24 * The default for all devices is "auto", which means that devices may be
25 * subject to automatic power management, depending on their drivers.
26 * Changing this attribute to "on" prevents the driver from power managing
27 * the device at run time. Doing that while the device is suspended causes
28 * it to be woken up.
29 *
30 * wakeup - Report/change current wakeup option for device
31 *
32 * Some devices support "wakeup" events, which are hardware signals
33 * used to activate devices from suspended or low power states. Such
34 * devices have one of three values for the sysfs power/wakeup file:
35 *
36 * + "enabled\n" to issue the events;
37 * + "disabled\n" not to do so; or
38 * + "\n" for temporary or permanent inability to issue wakeup.
39 *
40 * (For example, unconfigured USB devices can't issue wakeups.)
41 *
42 * Familiar examples of devices that can issue wakeup events include
43 * keyboards and mice (both PS2 and USB styles), power buttons, modems,
44 * "Wake-On-LAN" Ethernet links, GPIO lines, and more. Some events
45 * will wake the entire system from a suspend state; others may just
46 * wake up the device (if the system as a whole is already active).
47 * Some wakeup events use normal IRQ lines; other use special out
48 * of band signaling.
49 *
50 * It is the responsibility of device drivers to enable (or disable)
51 * wakeup signaling as part of changing device power states, respecting
52 * the policy choices provided through the driver model.
53 *
54 * Devices may not be able to generate wakeup events from all power
55 * states. Also, the events may be ignored in some configurations;
56 * for example, they might need help from other devices that aren't
57 * active, or which may have wakeup disabled. Some drivers rely on
58 * wakeup events internally (unless they are disabled), keeping
59 * their hardware in low power modes whenever they're unused. This
60 * saves runtime power, without requiring system-wide sleep states.
61 *
62 * async - Report/change current async suspend setting for the device
63 *
64 * Asynchronous suspend and resume of the device during system-wide power
65 * state transitions can be enabled by writing "enabled" to this file.
66 * Analogously, if "disabled" is written to this file, the device will be
67 * suspended and resumed synchronously.
68 *
69 * All devices have one of the following two values for power/async:
70 *
71 * + "enabled\n" to permit the asynchronous suspend/resume of the device;
72 * + "disabled\n" to forbid it;
73 *
74 * NOTE: It generally is unsafe to permit the asynchronous suspend/resume
75 * of a device unless it is certain that all of the PM dependencies of the
76 * device are known to the PM core. However, for some devices this
77 * attribute is set to "enabled" by bus type code or device drivers and in
78 * that cases it should be safe to leave the default value.
79 *
80 * autosuspend_delay_ms - Report/change a device's autosuspend_delay value
81 *
82 * Some drivers don't want to carry out a runtime suspend as soon as a
83 * device becomes idle; they want it always to remain idle for some period
84 * of time before suspending it. This period is the autosuspend_delay
85 * value (expressed in milliseconds) and it can be controlled by the user.
86 * If the value is negative then the device will never be runtime
87 * suspended.
88 *
89 * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
90 * value are used only if the driver calls pm_runtime_use_autosuspend().
91 *
92 * wakeup_count - Report the number of wakeup events related to the device
93 */
94
95const char power_group_name[] = "power";
96EXPORT_SYMBOL_GPL(power_group_name);
97
98static const char ctrl_auto[] = "auto";
99static const char ctrl_on[] = "on";
100
101static ssize_t control_show(struct device *dev, struct device_attribute *attr,
102 char *buf)
103{
104 return sprintf(buf, "%s\n",
105 dev->power.runtime_auto ? ctrl_auto : ctrl_on);
106}
107
108static ssize_t control_store(struct device * dev, struct device_attribute *attr,
109 const char * buf, size_t n)
110{
111 device_lock(dev);
112 if (sysfs_streq(buf, ctrl_auto))
113 pm_runtime_allow(dev);
114 else if (sysfs_streq(buf, ctrl_on))
115 pm_runtime_forbid(dev);
116 else
117 n = -EINVAL;
118 device_unlock(dev);
119 return n;
120}
121
122static DEVICE_ATTR_RW(control);
123
124static ssize_t runtime_active_time_show(struct device *dev,
125 struct device_attribute *attr, char *buf)
126{
127 int ret;
128 u64 tmp = pm_runtime_active_time(dev);
129 do_div(tmp, NSEC_PER_MSEC);
130 ret = sprintf(buf, "%llu\n", tmp);
131 return ret;
132}
133
134static DEVICE_ATTR_RO(runtime_active_time);
135
136static ssize_t runtime_suspended_time_show(struct device *dev,
137 struct device_attribute *attr, char *buf)
138{
139 int ret;
140 u64 tmp = pm_runtime_suspended_time(dev);
141 do_div(tmp, NSEC_PER_MSEC);
142 ret = sprintf(buf, "%llu\n", tmp);
143 return ret;
144}
145
146static DEVICE_ATTR_RO(runtime_suspended_time);
147
148static ssize_t runtime_status_show(struct device *dev,
149 struct device_attribute *attr, char *buf)
150{
151 const char *p;
152
153 if (dev->power.runtime_error) {
154 p = "error\n";
155 } else if (dev->power.disable_depth) {
156 p = "unsupported\n";
157 } else {
158 switch (dev->power.runtime_status) {
159 case RPM_SUSPENDED:
160 p = "suspended\n";
161 break;
162 case RPM_SUSPENDING:
163 p = "suspending\n";
164 break;
165 case RPM_RESUMING:
166 p = "resuming\n";
167 break;
168 case RPM_ACTIVE:
169 p = "active\n";
170 break;
171 default:
172 return -EIO;
173 }
174 }
175 return sprintf(buf, p);
176}
177
178static DEVICE_ATTR_RO(runtime_status);
179
180static ssize_t autosuspend_delay_ms_show(struct device *dev,
181 struct device_attribute *attr, char *buf)
182{
183 if (!dev->power.use_autosuspend)
184 return -EIO;
185 return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
186}
187
188static ssize_t autosuspend_delay_ms_store(struct device *dev,
189 struct device_attribute *attr, const char *buf, size_t n)
190{
191 long delay;
192
193 if (!dev->power.use_autosuspend)
194 return -EIO;
195
196 if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay)
197 return -EINVAL;
198
199 device_lock(dev);
200 pm_runtime_set_autosuspend_delay(dev, delay);
201 device_unlock(dev);
202 return n;
203}
204
205static DEVICE_ATTR_RW(autosuspend_delay_ms);
206
207static ssize_t pm_qos_resume_latency_us_show(struct device *dev,
208 struct device_attribute *attr,
209 char *buf)
210{
211 s32 value = dev_pm_qos_requested_resume_latency(dev);
212
213 if (value == 0)
214 return sprintf(buf, "n/a\n");
215 if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
216 value = 0;
217
218 return sprintf(buf, "%d\n", value);
219}
220
221static ssize_t pm_qos_resume_latency_us_store(struct device *dev,
222 struct device_attribute *attr,
223 const char *buf, size_t n)
224{
225 s32 value;
226 int ret;
227
228 if (!kstrtos32(buf, 0, &value)) {
229 /*
230 * Prevent users from writing negative or "no constraint" values
231 * directly.
232 */
233 if (value < 0 || value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
234 return -EINVAL;
235
236 if (value == 0)
237 value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
238 } else if (sysfs_streq(buf, "n/a")) {
239 value = 0;
240 } else {
241 return -EINVAL;
242 }
243
244 ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req,
245 value);
246 return ret < 0 ? ret : n;
247}
248
249static DEVICE_ATTR_RW(pm_qos_resume_latency_us);
250
251static ssize_t pm_qos_latency_tolerance_us_show(struct device *dev,
252 struct device_attribute *attr,
253 char *buf)
254{
255 s32 value = dev_pm_qos_get_user_latency_tolerance(dev);
256
257 if (value < 0)
258 return sprintf(buf, "auto\n");
259 if (value == PM_QOS_LATENCY_ANY)
260 return sprintf(buf, "any\n");
261
262 return sprintf(buf, "%d\n", value);
263}
264
265static ssize_t pm_qos_latency_tolerance_us_store(struct device *dev,
266 struct device_attribute *attr,
267 const char *buf, size_t n)
268{
269 s32 value;
270 int ret;
271
272 if (kstrtos32(buf, 0, &value) == 0) {
273 /* Users can't write negative values directly */
274 if (value < 0)
275 return -EINVAL;
276 } else {
277 if (sysfs_streq(buf, "auto"))
278 value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;
279 else if (sysfs_streq(buf, "any"))
280 value = PM_QOS_LATENCY_ANY;
281 else
282 return -EINVAL;
283 }
284 ret = dev_pm_qos_update_user_latency_tolerance(dev, value);
285 return ret < 0 ? ret : n;
286}
287
288static DEVICE_ATTR_RW(pm_qos_latency_tolerance_us);
289
290static ssize_t pm_qos_no_power_off_show(struct device *dev,
291 struct device_attribute *attr,
292 char *buf)
293{
294 return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
295 & PM_QOS_FLAG_NO_POWER_OFF));
296}
297
298static ssize_t pm_qos_no_power_off_store(struct device *dev,
299 struct device_attribute *attr,
300 const char *buf, size_t n)
301{
302 int ret;
303
304 if (kstrtoint(buf, 0, &ret))
305 return -EINVAL;
306
307 if (ret != 0 && ret != 1)
308 return -EINVAL;
309
310 ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret);
311 return ret < 0 ? ret : n;
312}
313
314static DEVICE_ATTR_RW(pm_qos_no_power_off);
315
316#ifdef CONFIG_PM_SLEEP
317static const char _enabled[] = "enabled";
318static const char _disabled[] = "disabled";
319
320static ssize_t wakeup_show(struct device *dev, struct device_attribute *attr,
321 char *buf)
322{
323 return sprintf(buf, "%s\n", device_can_wakeup(dev)
324 ? (device_may_wakeup(dev) ? _enabled : _disabled)
325 : "");
326}
327
328static ssize_t wakeup_store(struct device *dev, struct device_attribute *attr,
329 const char *buf, size_t n)
330{
331 if (!device_can_wakeup(dev))
332 return -EINVAL;
333
334 if (sysfs_streq(buf, _enabled))
335 device_set_wakeup_enable(dev, 1);
336 else if (sysfs_streq(buf, _disabled))
337 device_set_wakeup_enable(dev, 0);
338 else
339 return -EINVAL;
340 return n;
341}
342
343static DEVICE_ATTR_RW(wakeup);
344
345static ssize_t wakeup_count_show(struct device *dev,
346 struct device_attribute *attr, char *buf)
347{
348 unsigned long count = 0;
349 bool enabled = false;
350
351 spin_lock_irq(&dev->power.lock);
352 if (dev->power.wakeup) {
353 count = dev->power.wakeup->wakeup_count;
354 enabled = true;
355 }
356 spin_unlock_irq(&dev->power.lock);
357 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
358}
359
360static DEVICE_ATTR_RO(wakeup_count);
361
362static ssize_t wakeup_active_count_show(struct device *dev,
363 struct device_attribute *attr,
364 char *buf)
365{
366 unsigned long count = 0;
367 bool enabled = false;
368
369 spin_lock_irq(&dev->power.lock);
370 if (dev->power.wakeup) {
371 count = dev->power.wakeup->active_count;
372 enabled = true;
373 }
374 spin_unlock_irq(&dev->power.lock);
375 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
376}
377
378static DEVICE_ATTR_RO(wakeup_active_count);
379
380static ssize_t wakeup_abort_count_show(struct device *dev,
381 struct device_attribute *attr,
382 char *buf)
383{
384 unsigned long count = 0;
385 bool enabled = false;
386
387 spin_lock_irq(&dev->power.lock);
388 if (dev->power.wakeup) {
389 count = dev->power.wakeup->wakeup_count;
390 enabled = true;
391 }
392 spin_unlock_irq(&dev->power.lock);
393 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
394}
395
396static DEVICE_ATTR_RO(wakeup_abort_count);
397
398static ssize_t wakeup_expire_count_show(struct device *dev,
399 struct device_attribute *attr,
400 char *buf)
401{
402 unsigned long count = 0;
403 bool enabled = false;
404
405 spin_lock_irq(&dev->power.lock);
406 if (dev->power.wakeup) {
407 count = dev->power.wakeup->expire_count;
408 enabled = true;
409 }
410 spin_unlock_irq(&dev->power.lock);
411 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
412}
413
414static DEVICE_ATTR_RO(wakeup_expire_count);
415
416static ssize_t wakeup_active_show(struct device *dev,
417 struct device_attribute *attr, char *buf)
418{
419 unsigned int active = 0;
420 bool enabled = false;
421
422 spin_lock_irq(&dev->power.lock);
423 if (dev->power.wakeup) {
424 active = dev->power.wakeup->active;
425 enabled = true;
426 }
427 spin_unlock_irq(&dev->power.lock);
428 return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
429}
430
431static DEVICE_ATTR_RO(wakeup_active);
432
433static ssize_t wakeup_total_time_ms_show(struct device *dev,
434 struct device_attribute *attr,
435 char *buf)
436{
437 s64 msec = 0;
438 bool enabled = false;
439
440 spin_lock_irq(&dev->power.lock);
441 if (dev->power.wakeup) {
442 msec = ktime_to_ms(dev->power.wakeup->total_time);
443 enabled = true;
444 }
445 spin_unlock_irq(&dev->power.lock);
446 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
447}
448
449static DEVICE_ATTR_RO(wakeup_total_time_ms);
450
451static ssize_t wakeup_max_time_ms_show(struct device *dev,
452 struct device_attribute *attr, char *buf)
453{
454 s64 msec = 0;
455 bool enabled = false;
456
457 spin_lock_irq(&dev->power.lock);
458 if (dev->power.wakeup) {
459 msec = ktime_to_ms(dev->power.wakeup->max_time);
460 enabled = true;
461 }
462 spin_unlock_irq(&dev->power.lock);
463 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
464}
465
466static DEVICE_ATTR_RO(wakeup_max_time_ms);
467
468static ssize_t wakeup_last_time_ms_show(struct device *dev,
469 struct device_attribute *attr,
470 char *buf)
471{
472 s64 msec = 0;
473 bool enabled = false;
474
475 spin_lock_irq(&dev->power.lock);
476 if (dev->power.wakeup) {
477 msec = ktime_to_ms(dev->power.wakeup->last_time);
478 enabled = true;
479 }
480 spin_unlock_irq(&dev->power.lock);
481 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
482}
483
484static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid,
485 kgid_t kgid)
486{
487 if (dev->power.wakeup && dev->power.wakeup->dev)
488 return device_change_owner(dev->power.wakeup->dev, kuid, kgid);
489 return 0;
490}
491
492static DEVICE_ATTR_RO(wakeup_last_time_ms);
493
494#ifdef CONFIG_PM_AUTOSLEEP
495static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev,
496 struct device_attribute *attr,
497 char *buf)
498{
499 s64 msec = 0;
500 bool enabled = false;
501
502 spin_lock_irq(&dev->power.lock);
503 if (dev->power.wakeup) {
504 msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
505 enabled = true;
506 }
507 spin_unlock_irq(&dev->power.lock);
508 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
509}
510
511static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms);
512#endif /* CONFIG_PM_AUTOSLEEP */
513#else /* CONFIG_PM_SLEEP */
514static inline int dpm_sysfs_wakeup_change_owner(struct device *dev, kuid_t kuid,
515 kgid_t kgid)
516{
517 return 0;
518}
519#endif
520
521#ifdef CONFIG_PM_ADVANCED_DEBUG
522static ssize_t runtime_usage_show(struct device *dev,
523 struct device_attribute *attr, char *buf)
524{
525 return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
526}
527static DEVICE_ATTR_RO(runtime_usage);
528
529static ssize_t runtime_active_kids_show(struct device *dev,
530 struct device_attribute *attr,
531 char *buf)
532{
533 return sprintf(buf, "%d\n", dev->power.ignore_children ?
534 0 : atomic_read(&dev->power.child_count));
535}
536static DEVICE_ATTR_RO(runtime_active_kids);
537
538static ssize_t runtime_enabled_show(struct device *dev,
539 struct device_attribute *attr, char *buf)
540{
541 if (dev->power.disable_depth && (dev->power.runtime_auto == false))
542 return sprintf(buf, "disabled & forbidden\n");
543 if (dev->power.disable_depth)
544 return sprintf(buf, "disabled\n");
545 if (dev->power.runtime_auto == false)
546 return sprintf(buf, "forbidden\n");
547 return sprintf(buf, "enabled\n");
548}
549static DEVICE_ATTR_RO(runtime_enabled);
550
551#ifdef CONFIG_PM_SLEEP
552static ssize_t async_show(struct device *dev, struct device_attribute *attr,
553 char *buf)
554{
555 return sprintf(buf, "%s\n",
556 device_async_suspend_enabled(dev) ?
557 _enabled : _disabled);
558}
559
560static ssize_t async_store(struct device *dev, struct device_attribute *attr,
561 const char *buf, size_t n)
562{
563 if (sysfs_streq(buf, _enabled))
564 device_enable_async_suspend(dev);
565 else if (sysfs_streq(buf, _disabled))
566 device_disable_async_suspend(dev);
567 else
568 return -EINVAL;
569 return n;
570}
571
572static DEVICE_ATTR_RW(async);
573
574#endif /* CONFIG_PM_SLEEP */
575#endif /* CONFIG_PM_ADVANCED_DEBUG */
576
577static struct attribute *power_attrs[] = {
578#ifdef CONFIG_PM_ADVANCED_DEBUG
579#ifdef CONFIG_PM_SLEEP
580 &dev_attr_async.attr,
581#endif
582 &dev_attr_runtime_status.attr,
583 &dev_attr_runtime_usage.attr,
584 &dev_attr_runtime_active_kids.attr,
585 &dev_attr_runtime_enabled.attr,
586#endif /* CONFIG_PM_ADVANCED_DEBUG */
587 NULL,
588};
589static const struct attribute_group pm_attr_group = {
590 .name = power_group_name,
591 .attrs = power_attrs,
592};
593
594static struct attribute *wakeup_attrs[] = {
595#ifdef CONFIG_PM_SLEEP
596 &dev_attr_wakeup.attr,
597 &dev_attr_wakeup_count.attr,
598 &dev_attr_wakeup_active_count.attr,
599 &dev_attr_wakeup_abort_count.attr,
600 &dev_attr_wakeup_expire_count.attr,
601 &dev_attr_wakeup_active.attr,
602 &dev_attr_wakeup_total_time_ms.attr,
603 &dev_attr_wakeup_max_time_ms.attr,
604 &dev_attr_wakeup_last_time_ms.attr,
605#ifdef CONFIG_PM_AUTOSLEEP
606 &dev_attr_wakeup_prevent_sleep_time_ms.attr,
607#endif
608#endif
609 NULL,
610};
611static const struct attribute_group pm_wakeup_attr_group = {
612 .name = power_group_name,
613 .attrs = wakeup_attrs,
614};
615
616static struct attribute *runtime_attrs[] = {
617#ifndef CONFIG_PM_ADVANCED_DEBUG
618 &dev_attr_runtime_status.attr,
619#endif
620 &dev_attr_control.attr,
621 &dev_attr_runtime_suspended_time.attr,
622 &dev_attr_runtime_active_time.attr,
623 &dev_attr_autosuspend_delay_ms.attr,
624 NULL,
625};
626static const struct attribute_group pm_runtime_attr_group = {
627 .name = power_group_name,
628 .attrs = runtime_attrs,
629};
630
631static struct attribute *pm_qos_resume_latency_attrs[] = {
632 &dev_attr_pm_qos_resume_latency_us.attr,
633 NULL,
634};
635static const struct attribute_group pm_qos_resume_latency_attr_group = {
636 .name = power_group_name,
637 .attrs = pm_qos_resume_latency_attrs,
638};
639
640static struct attribute *pm_qos_latency_tolerance_attrs[] = {
641 &dev_attr_pm_qos_latency_tolerance_us.attr,
642 NULL,
643};
644static const struct attribute_group pm_qos_latency_tolerance_attr_group = {
645 .name = power_group_name,
646 .attrs = pm_qos_latency_tolerance_attrs,
647};
648
649static struct attribute *pm_qos_flags_attrs[] = {
650 &dev_attr_pm_qos_no_power_off.attr,
651 NULL,
652};
653static const struct attribute_group pm_qos_flags_attr_group = {
654 .name = power_group_name,
655 .attrs = pm_qos_flags_attrs,
656};
657
658int dpm_sysfs_add(struct device *dev)
659{
660 int rc;
661
662 /* No need to create PM sysfs if explicitly disabled. */
663 if (device_pm_not_required(dev))
664 return 0;
665
666 rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
667 if (rc)
668 return rc;
669
670 if (!pm_runtime_has_no_callbacks(dev)) {
671 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
672 if (rc)
673 goto err_out;
674 }
675 if (device_can_wakeup(dev)) {
676 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
677 if (rc)
678 goto err_runtime;
679 }
680 if (dev->power.set_latency_tolerance) {
681 rc = sysfs_merge_group(&dev->kobj,
682 &pm_qos_latency_tolerance_attr_group);
683 if (rc)
684 goto err_wakeup;
685 }
686 rc = pm_wakeup_source_sysfs_add(dev);
687 if (rc)
688 goto err_latency;
689 return 0;
690
691 err_latency:
692 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
693 err_wakeup:
694 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
695 err_runtime:
696 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
697 err_out:
698 sysfs_remove_group(&dev->kobj, &pm_attr_group);
699 return rc;
700}
701
702int dpm_sysfs_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid)
703{
704 int rc;
705
706 if (device_pm_not_required(dev))
707 return 0;
708
709 rc = sysfs_group_change_owner(&dev->kobj, &pm_attr_group, kuid, kgid);
710 if (rc)
711 return rc;
712
713 if (!pm_runtime_has_no_callbacks(dev)) {
714 rc = sysfs_group_change_owner(
715 &dev->kobj, &pm_runtime_attr_group, kuid, kgid);
716 if (rc)
717 return rc;
718 }
719
720 if (device_can_wakeup(dev)) {
721 rc = sysfs_group_change_owner(&dev->kobj, &pm_wakeup_attr_group,
722 kuid, kgid);
723 if (rc)
724 return rc;
725
726 rc = dpm_sysfs_wakeup_change_owner(dev, kuid, kgid);
727 if (rc)
728 return rc;
729 }
730
731 if (dev->power.set_latency_tolerance) {
732 rc = sysfs_group_change_owner(
733 &dev->kobj, &pm_qos_latency_tolerance_attr_group, kuid,
734 kgid);
735 if (rc)
736 return rc;
737 }
738 return 0;
739}
740
741int wakeup_sysfs_add(struct device *dev)
742{
743 int ret = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
744
745 if (!ret)
746 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
747
748 return ret;
749}
750
751void wakeup_sysfs_remove(struct device *dev)
752{
753 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
754 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
755}
756
757int pm_qos_sysfs_add_resume_latency(struct device *dev)
758{
759 return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
760}
761
762void pm_qos_sysfs_remove_resume_latency(struct device *dev)
763{
764 sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
765}
766
767int pm_qos_sysfs_add_flags(struct device *dev)
768{
769 return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group);
770}
771
772void pm_qos_sysfs_remove_flags(struct device *dev)
773{
774 sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
775}
776
777int pm_qos_sysfs_add_latency_tolerance(struct device *dev)
778{
779 return sysfs_merge_group(&dev->kobj,
780 &pm_qos_latency_tolerance_attr_group);
781}
782
783void pm_qos_sysfs_remove_latency_tolerance(struct device *dev)
784{
785 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
786}
787
788void rpm_sysfs_remove(struct device *dev)
789{
790 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
791}
792
793void dpm_sysfs_remove(struct device *dev)
794{
795 if (device_pm_not_required(dev))
796 return;
797 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
798 dev_pm_qos_constraints_destroy(dev);
799 rpm_sysfs_remove(dev);
800 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
801 sysfs_remove_group(&dev->kobj, &pm_attr_group);
802}
1/*
2 * drivers/base/power/sysfs.c - sysfs entries for device PM
3 */
4
5#include <linux/device.h>
6#include <linux/string.h>
7#include <linux/pm_runtime.h>
8#include <linux/atomic.h>
9#include <linux/jiffies.h>
10#include "power.h"
11
12/*
13 * control - Report/change current runtime PM setting of the device
14 *
15 * Runtime power management of a device can be blocked with the help of
16 * this attribute. All devices have one of the following two values for
17 * the power/control file:
18 *
19 * + "auto\n" to allow the device to be power managed at run time;
20 * + "on\n" to prevent the device from being power managed at run time;
21 *
22 * The default for all devices is "auto", which means that devices may be
23 * subject to automatic power management, depending on their drivers.
24 * Changing this attribute to "on" prevents the driver from power managing
25 * the device at run time. Doing that while the device is suspended causes
26 * it to be woken up.
27 *
28 * wakeup - Report/change current wakeup option for device
29 *
30 * Some devices support "wakeup" events, which are hardware signals
31 * used to activate devices from suspended or low power states. Such
32 * devices have one of three values for the sysfs power/wakeup file:
33 *
34 * + "enabled\n" to issue the events;
35 * + "disabled\n" not to do so; or
36 * + "\n" for temporary or permanent inability to issue wakeup.
37 *
38 * (For example, unconfigured USB devices can't issue wakeups.)
39 *
40 * Familiar examples of devices that can issue wakeup events include
41 * keyboards and mice (both PS2 and USB styles), power buttons, modems,
42 * "Wake-On-LAN" Ethernet links, GPIO lines, and more. Some events
43 * will wake the entire system from a suspend state; others may just
44 * wake up the device (if the system as a whole is already active).
45 * Some wakeup events use normal IRQ lines; other use special out
46 * of band signaling.
47 *
48 * It is the responsibility of device drivers to enable (or disable)
49 * wakeup signaling as part of changing device power states, respecting
50 * the policy choices provided through the driver model.
51 *
52 * Devices may not be able to generate wakeup events from all power
53 * states. Also, the events may be ignored in some configurations;
54 * for example, they might need help from other devices that aren't
55 * active, or which may have wakeup disabled. Some drivers rely on
56 * wakeup events internally (unless they are disabled), keeping
57 * their hardware in low power modes whenever they're unused. This
58 * saves runtime power, without requiring system-wide sleep states.
59 *
60 * async - Report/change current async suspend setting for the device
61 *
62 * Asynchronous suspend and resume of the device during system-wide power
63 * state transitions can be enabled by writing "enabled" to this file.
64 * Analogously, if "disabled" is written to this file, the device will be
65 * suspended and resumed synchronously.
66 *
67 * All devices have one of the following two values for power/async:
68 *
69 * + "enabled\n" to permit the asynchronous suspend/resume of the device;
70 * + "disabled\n" to forbid it;
71 *
72 * NOTE: It generally is unsafe to permit the asynchronous suspend/resume
73 * of a device unless it is certain that all of the PM dependencies of the
74 * device are known to the PM core. However, for some devices this
75 * attribute is set to "enabled" by bus type code or device drivers and in
76 * that cases it should be safe to leave the default value.
77 *
78 * autosuspend_delay_ms - Report/change a device's autosuspend_delay value
79 *
80 * Some drivers don't want to carry out a runtime suspend as soon as a
81 * device becomes idle; they want it always to remain idle for some period
82 * of time before suspending it. This period is the autosuspend_delay
83 * value (expressed in milliseconds) and it can be controlled by the user.
84 * If the value is negative then the device will never be runtime
85 * suspended.
86 *
87 * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
88 * value are used only if the driver calls pm_runtime_use_autosuspend().
89 *
90 * wakeup_count - Report the number of wakeup events related to the device
91 */
92
93static const char enabled[] = "enabled";
94static const char disabled[] = "disabled";
95
96const char power_group_name[] = "power";
97EXPORT_SYMBOL_GPL(power_group_name);
98
99#ifdef CONFIG_PM_RUNTIME
100static const char ctrl_auto[] = "auto";
101static const char ctrl_on[] = "on";
102
103static ssize_t control_show(struct device *dev, struct device_attribute *attr,
104 char *buf)
105{
106 return sprintf(buf, "%s\n",
107 dev->power.runtime_auto ? ctrl_auto : ctrl_on);
108}
109
110static ssize_t control_store(struct device * dev, struct device_attribute *attr,
111 const char * buf, size_t n)
112{
113 char *cp;
114 int len = n;
115
116 cp = memchr(buf, '\n', n);
117 if (cp)
118 len = cp - buf;
119 device_lock(dev);
120 if (len == sizeof ctrl_auto - 1 && strncmp(buf, ctrl_auto, len) == 0)
121 pm_runtime_allow(dev);
122 else if (len == sizeof ctrl_on - 1 && strncmp(buf, ctrl_on, len) == 0)
123 pm_runtime_forbid(dev);
124 else
125 n = -EINVAL;
126 device_unlock(dev);
127 return n;
128}
129
130static DEVICE_ATTR(control, 0644, control_show, control_store);
131
132static ssize_t rtpm_active_time_show(struct device *dev,
133 struct device_attribute *attr, char *buf)
134{
135 int ret;
136 spin_lock_irq(&dev->power.lock);
137 update_pm_runtime_accounting(dev);
138 ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies));
139 spin_unlock_irq(&dev->power.lock);
140 return ret;
141}
142
143static DEVICE_ATTR(runtime_active_time, 0444, rtpm_active_time_show, NULL);
144
145static ssize_t rtpm_suspended_time_show(struct device *dev,
146 struct device_attribute *attr, char *buf)
147{
148 int ret;
149 spin_lock_irq(&dev->power.lock);
150 update_pm_runtime_accounting(dev);
151 ret = sprintf(buf, "%i\n",
152 jiffies_to_msecs(dev->power.suspended_jiffies));
153 spin_unlock_irq(&dev->power.lock);
154 return ret;
155}
156
157static DEVICE_ATTR(runtime_suspended_time, 0444, rtpm_suspended_time_show, NULL);
158
159static ssize_t rtpm_status_show(struct device *dev,
160 struct device_attribute *attr, char *buf)
161{
162 const char *p;
163
164 if (dev->power.runtime_error) {
165 p = "error\n";
166 } else if (dev->power.disable_depth) {
167 p = "unsupported\n";
168 } else {
169 switch (dev->power.runtime_status) {
170 case RPM_SUSPENDED:
171 p = "suspended\n";
172 break;
173 case RPM_SUSPENDING:
174 p = "suspending\n";
175 break;
176 case RPM_RESUMING:
177 p = "resuming\n";
178 break;
179 case RPM_ACTIVE:
180 p = "active\n";
181 break;
182 default:
183 return -EIO;
184 }
185 }
186 return sprintf(buf, p);
187}
188
189static DEVICE_ATTR(runtime_status, 0444, rtpm_status_show, NULL);
190
191static ssize_t autosuspend_delay_ms_show(struct device *dev,
192 struct device_attribute *attr, char *buf)
193{
194 if (!dev->power.use_autosuspend)
195 return -EIO;
196 return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
197}
198
199static ssize_t autosuspend_delay_ms_store(struct device *dev,
200 struct device_attribute *attr, const char *buf, size_t n)
201{
202 long delay;
203
204 if (!dev->power.use_autosuspend)
205 return -EIO;
206
207 if (strict_strtol(buf, 10, &delay) != 0 || delay != (int) delay)
208 return -EINVAL;
209
210 device_lock(dev);
211 pm_runtime_set_autosuspend_delay(dev, delay);
212 device_unlock(dev);
213 return n;
214}
215
216static DEVICE_ATTR(autosuspend_delay_ms, 0644, autosuspend_delay_ms_show,
217 autosuspend_delay_ms_store);
218
219#endif /* CONFIG_PM_RUNTIME */
220
221#ifdef CONFIG_PM_SLEEP
222static ssize_t
223wake_show(struct device * dev, struct device_attribute *attr, char * buf)
224{
225 return sprintf(buf, "%s\n", device_can_wakeup(dev)
226 ? (device_may_wakeup(dev) ? enabled : disabled)
227 : "");
228}
229
230static ssize_t
231wake_store(struct device * dev, struct device_attribute *attr,
232 const char * buf, size_t n)
233{
234 char *cp;
235 int len = n;
236
237 if (!device_can_wakeup(dev))
238 return -EINVAL;
239
240 cp = memchr(buf, '\n', n);
241 if (cp)
242 len = cp - buf;
243 if (len == sizeof enabled - 1
244 && strncmp(buf, enabled, sizeof enabled - 1) == 0)
245 device_set_wakeup_enable(dev, 1);
246 else if (len == sizeof disabled - 1
247 && strncmp(buf, disabled, sizeof disabled - 1) == 0)
248 device_set_wakeup_enable(dev, 0);
249 else
250 return -EINVAL;
251 return n;
252}
253
254static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
255
256static ssize_t wakeup_count_show(struct device *dev,
257 struct device_attribute *attr, char *buf)
258{
259 unsigned long count = 0;
260 bool enabled = false;
261
262 spin_lock_irq(&dev->power.lock);
263 if (dev->power.wakeup) {
264 count = dev->power.wakeup->event_count;
265 enabled = true;
266 }
267 spin_unlock_irq(&dev->power.lock);
268 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
269}
270
271static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL);
272
273static ssize_t wakeup_active_count_show(struct device *dev,
274 struct device_attribute *attr, char *buf)
275{
276 unsigned long count = 0;
277 bool enabled = false;
278
279 spin_lock_irq(&dev->power.lock);
280 if (dev->power.wakeup) {
281 count = dev->power.wakeup->active_count;
282 enabled = true;
283 }
284 spin_unlock_irq(&dev->power.lock);
285 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
286}
287
288static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL);
289
290static ssize_t wakeup_hit_count_show(struct device *dev,
291 struct device_attribute *attr, char *buf)
292{
293 unsigned long count = 0;
294 bool enabled = false;
295
296 spin_lock_irq(&dev->power.lock);
297 if (dev->power.wakeup) {
298 count = dev->power.wakeup->hit_count;
299 enabled = true;
300 }
301 spin_unlock_irq(&dev->power.lock);
302 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
303}
304
305static DEVICE_ATTR(wakeup_hit_count, 0444, wakeup_hit_count_show, NULL);
306
307static ssize_t wakeup_active_show(struct device *dev,
308 struct device_attribute *attr, char *buf)
309{
310 unsigned int active = 0;
311 bool enabled = false;
312
313 spin_lock_irq(&dev->power.lock);
314 if (dev->power.wakeup) {
315 active = dev->power.wakeup->active;
316 enabled = true;
317 }
318 spin_unlock_irq(&dev->power.lock);
319 return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
320}
321
322static DEVICE_ATTR(wakeup_active, 0444, wakeup_active_show, NULL);
323
324static ssize_t wakeup_total_time_show(struct device *dev,
325 struct device_attribute *attr, char *buf)
326{
327 s64 msec = 0;
328 bool enabled = false;
329
330 spin_lock_irq(&dev->power.lock);
331 if (dev->power.wakeup) {
332 msec = ktime_to_ms(dev->power.wakeup->total_time);
333 enabled = true;
334 }
335 spin_unlock_irq(&dev->power.lock);
336 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
337}
338
339static DEVICE_ATTR(wakeup_total_time_ms, 0444, wakeup_total_time_show, NULL);
340
341static ssize_t wakeup_max_time_show(struct device *dev,
342 struct device_attribute *attr, char *buf)
343{
344 s64 msec = 0;
345 bool enabled = false;
346
347 spin_lock_irq(&dev->power.lock);
348 if (dev->power.wakeup) {
349 msec = ktime_to_ms(dev->power.wakeup->max_time);
350 enabled = true;
351 }
352 spin_unlock_irq(&dev->power.lock);
353 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
354}
355
356static DEVICE_ATTR(wakeup_max_time_ms, 0444, wakeup_max_time_show, NULL);
357
358static ssize_t wakeup_last_time_show(struct device *dev,
359 struct device_attribute *attr, char *buf)
360{
361 s64 msec = 0;
362 bool enabled = false;
363
364 spin_lock_irq(&dev->power.lock);
365 if (dev->power.wakeup) {
366 msec = ktime_to_ms(dev->power.wakeup->last_time);
367 enabled = true;
368 }
369 spin_unlock_irq(&dev->power.lock);
370 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
371}
372
373static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL);
374#endif /* CONFIG_PM_SLEEP */
375
376#ifdef CONFIG_PM_ADVANCED_DEBUG
377#ifdef CONFIG_PM_RUNTIME
378
379static ssize_t rtpm_usagecount_show(struct device *dev,
380 struct device_attribute *attr, char *buf)
381{
382 return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
383}
384
385static ssize_t rtpm_children_show(struct device *dev,
386 struct device_attribute *attr, char *buf)
387{
388 return sprintf(buf, "%d\n", dev->power.ignore_children ?
389 0 : atomic_read(&dev->power.child_count));
390}
391
392static ssize_t rtpm_enabled_show(struct device *dev,
393 struct device_attribute *attr, char *buf)
394{
395 if ((dev->power.disable_depth) && (dev->power.runtime_auto == false))
396 return sprintf(buf, "disabled & forbidden\n");
397 else if (dev->power.disable_depth)
398 return sprintf(buf, "disabled\n");
399 else if (dev->power.runtime_auto == false)
400 return sprintf(buf, "forbidden\n");
401 return sprintf(buf, "enabled\n");
402}
403
404static DEVICE_ATTR(runtime_usage, 0444, rtpm_usagecount_show, NULL);
405static DEVICE_ATTR(runtime_active_kids, 0444, rtpm_children_show, NULL);
406static DEVICE_ATTR(runtime_enabled, 0444, rtpm_enabled_show, NULL);
407
408#endif
409
410static ssize_t async_show(struct device *dev, struct device_attribute *attr,
411 char *buf)
412{
413 return sprintf(buf, "%s\n",
414 device_async_suspend_enabled(dev) ? enabled : disabled);
415}
416
417static ssize_t async_store(struct device *dev, struct device_attribute *attr,
418 const char *buf, size_t n)
419{
420 char *cp;
421 int len = n;
422
423 cp = memchr(buf, '\n', n);
424 if (cp)
425 len = cp - buf;
426 if (len == sizeof enabled - 1 && strncmp(buf, enabled, len) == 0)
427 device_enable_async_suspend(dev);
428 else if (len == sizeof disabled - 1 && strncmp(buf, disabled, len) == 0)
429 device_disable_async_suspend(dev);
430 else
431 return -EINVAL;
432 return n;
433}
434
435static DEVICE_ATTR(async, 0644, async_show, async_store);
436#endif /* CONFIG_PM_ADVANCED_DEBUG */
437
438static struct attribute *power_attrs[] = {
439#ifdef CONFIG_PM_ADVANCED_DEBUG
440#ifdef CONFIG_PM_SLEEP
441 &dev_attr_async.attr,
442#endif
443#ifdef CONFIG_PM_RUNTIME
444 &dev_attr_runtime_status.attr,
445 &dev_attr_runtime_usage.attr,
446 &dev_attr_runtime_active_kids.attr,
447 &dev_attr_runtime_enabled.attr,
448#endif
449#endif /* CONFIG_PM_ADVANCED_DEBUG */
450 NULL,
451};
452static struct attribute_group pm_attr_group = {
453 .name = power_group_name,
454 .attrs = power_attrs,
455};
456
457static struct attribute *wakeup_attrs[] = {
458#ifdef CONFIG_PM_SLEEP
459 &dev_attr_wakeup.attr,
460 &dev_attr_wakeup_count.attr,
461 &dev_attr_wakeup_active_count.attr,
462 &dev_attr_wakeup_hit_count.attr,
463 &dev_attr_wakeup_active.attr,
464 &dev_attr_wakeup_total_time_ms.attr,
465 &dev_attr_wakeup_max_time_ms.attr,
466 &dev_attr_wakeup_last_time_ms.attr,
467#endif
468 NULL,
469};
470static struct attribute_group pm_wakeup_attr_group = {
471 .name = power_group_name,
472 .attrs = wakeup_attrs,
473};
474
475static struct attribute *runtime_attrs[] = {
476#ifdef CONFIG_PM_RUNTIME
477#ifndef CONFIG_PM_ADVANCED_DEBUG
478 &dev_attr_runtime_status.attr,
479#endif
480 &dev_attr_control.attr,
481 &dev_attr_runtime_suspended_time.attr,
482 &dev_attr_runtime_active_time.attr,
483 &dev_attr_autosuspend_delay_ms.attr,
484#endif /* CONFIG_PM_RUNTIME */
485 NULL,
486};
487static struct attribute_group pm_runtime_attr_group = {
488 .name = power_group_name,
489 .attrs = runtime_attrs,
490};
491
492int dpm_sysfs_add(struct device *dev)
493{
494 int rc;
495
496 rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
497 if (rc)
498 return rc;
499
500 if (pm_runtime_callbacks_present(dev)) {
501 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
502 if (rc)
503 goto err_out;
504 }
505
506 if (device_can_wakeup(dev)) {
507 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
508 if (rc) {
509 if (pm_runtime_callbacks_present(dev))
510 sysfs_unmerge_group(&dev->kobj,
511 &pm_runtime_attr_group);
512 goto err_out;
513 }
514 }
515 return 0;
516
517 err_out:
518 sysfs_remove_group(&dev->kobj, &pm_attr_group);
519 return rc;
520}
521
522int wakeup_sysfs_add(struct device *dev)
523{
524 return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
525}
526
527void wakeup_sysfs_remove(struct device *dev)
528{
529 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
530}
531
532void rpm_sysfs_remove(struct device *dev)
533{
534 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
535}
536
537void dpm_sysfs_remove(struct device *dev)
538{
539 rpm_sysfs_remove(dev);
540 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
541 sysfs_remove_group(&dev->kobj, &pm_attr_group);
542}