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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/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
94const char power_group_name[] = "power";
95EXPORT_SYMBOL_GPL(power_group_name);
96
97static const char ctrl_auto[] = "auto";
98static const char ctrl_on[] = "on";
99
100static 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
107static 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
121static DEVICE_ATTR_RW(control);
122
123static 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
133static DEVICE_ATTR_RO(runtime_active_time);
134
135static 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
145static DEVICE_ATTR_RO(runtime_suspended_time);
146
147static 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
177static DEVICE_ATTR_RO(runtime_status);
178
179static 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
187static 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
204static DEVICE_ATTR_RW(autosuspend_delay_ms);
205
206static 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
220static 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
248static DEVICE_ATTR_RW(pm_qos_resume_latency_us);
249
250static 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
264static 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
287static DEVICE_ATTR_RW(pm_qos_latency_tolerance_us);
288
289static 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
297static 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
313static DEVICE_ATTR_RW(pm_qos_no_power_off);
314
315#ifdef CONFIG_PM_SLEEP
316static const char _enabled[] = "enabled";
317static const char _disabled[] = "disabled";
318
319static 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
327static 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
342static DEVICE_ATTR_RW(wakeup);
343
344static 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
359static DEVICE_ATTR_RO(wakeup_count);
360
361static 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
377static DEVICE_ATTR_RO(wakeup_active_count);
378
379static 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
395static DEVICE_ATTR_RO(wakeup_abort_count);
396
397static 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
413static DEVICE_ATTR_RO(wakeup_expire_count);
414
415static 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
430static DEVICE_ATTR_RO(wakeup_active);
431
432static 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
448static DEVICE_ATTR_RO(wakeup_total_time_ms);
449
450static 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
465static DEVICE_ATTR_RO(wakeup_max_time_ms);
466
467static 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
483static DEVICE_ATTR_RO(wakeup_last_time_ms);
484
485#ifdef CONFIG_PM_AUTOSLEEP
486static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev,
487 struct device_attribute *attr,
488 char *buf)
489{
490 s64 msec = 0;
491 bool enabled = false;
492
493 spin_lock_irq(&dev->power.lock);
494 if (dev->power.wakeup) {
495 msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
496 enabled = true;
497 }
498 spin_unlock_irq(&dev->power.lock);
499 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
500}
501
502static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms);
503#endif /* CONFIG_PM_AUTOSLEEP */
504#endif /* CONFIG_PM_SLEEP */
505
506#ifdef CONFIG_PM_ADVANCED_DEBUG
507static ssize_t runtime_usage_show(struct device *dev,
508 struct device_attribute *attr, char *buf)
509{
510 return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
511}
512static DEVICE_ATTR_RO(runtime_usage);
513
514static ssize_t runtime_active_kids_show(struct device *dev,
515 struct device_attribute *attr,
516 char *buf)
517{
518 return sprintf(buf, "%d\n", dev->power.ignore_children ?
519 0 : atomic_read(&dev->power.child_count));
520}
521static DEVICE_ATTR_RO(runtime_active_kids);
522
523static ssize_t runtime_enabled_show(struct device *dev,
524 struct device_attribute *attr, char *buf)
525{
526 if (dev->power.disable_depth && (dev->power.runtime_auto == false))
527 return sprintf(buf, "disabled & forbidden\n");
528 if (dev->power.disable_depth)
529 return sprintf(buf, "disabled\n");
530 if (dev->power.runtime_auto == false)
531 return sprintf(buf, "forbidden\n");
532 return sprintf(buf, "enabled\n");
533}
534static DEVICE_ATTR_RO(runtime_enabled);
535
536#ifdef CONFIG_PM_SLEEP
537static ssize_t async_show(struct device *dev, struct device_attribute *attr,
538 char *buf)
539{
540 return sprintf(buf, "%s\n",
541 device_async_suspend_enabled(dev) ?
542 _enabled : _disabled);
543}
544
545static ssize_t async_store(struct device *dev, struct device_attribute *attr,
546 const char *buf, size_t n)
547{
548 if (sysfs_streq(buf, _enabled))
549 device_enable_async_suspend(dev);
550 else if (sysfs_streq(buf, _disabled))
551 device_disable_async_suspend(dev);
552 else
553 return -EINVAL;
554 return n;
555}
556
557static DEVICE_ATTR_RW(async);
558
559#endif /* CONFIG_PM_SLEEP */
560#endif /* CONFIG_PM_ADVANCED_DEBUG */
561
562static struct attribute *power_attrs[] = {
563#ifdef CONFIG_PM_ADVANCED_DEBUG
564#ifdef CONFIG_PM_SLEEP
565 &dev_attr_async.attr,
566#endif
567 &dev_attr_runtime_status.attr,
568 &dev_attr_runtime_usage.attr,
569 &dev_attr_runtime_active_kids.attr,
570 &dev_attr_runtime_enabled.attr,
571#endif /* CONFIG_PM_ADVANCED_DEBUG */
572 NULL,
573};
574static const struct attribute_group pm_attr_group = {
575 .name = power_group_name,
576 .attrs = power_attrs,
577};
578
579static struct attribute *wakeup_attrs[] = {
580#ifdef CONFIG_PM_SLEEP
581 &dev_attr_wakeup.attr,
582 &dev_attr_wakeup_count.attr,
583 &dev_attr_wakeup_active_count.attr,
584 &dev_attr_wakeup_abort_count.attr,
585 &dev_attr_wakeup_expire_count.attr,
586 &dev_attr_wakeup_active.attr,
587 &dev_attr_wakeup_total_time_ms.attr,
588 &dev_attr_wakeup_max_time_ms.attr,
589 &dev_attr_wakeup_last_time_ms.attr,
590#ifdef CONFIG_PM_AUTOSLEEP
591 &dev_attr_wakeup_prevent_sleep_time_ms.attr,
592#endif
593#endif
594 NULL,
595};
596static const struct attribute_group pm_wakeup_attr_group = {
597 .name = power_group_name,
598 .attrs = wakeup_attrs,
599};
600
601static struct attribute *runtime_attrs[] = {
602#ifndef CONFIG_PM_ADVANCED_DEBUG
603 &dev_attr_runtime_status.attr,
604#endif
605 &dev_attr_control.attr,
606 &dev_attr_runtime_suspended_time.attr,
607 &dev_attr_runtime_active_time.attr,
608 &dev_attr_autosuspend_delay_ms.attr,
609 NULL,
610};
611static const struct attribute_group pm_runtime_attr_group = {
612 .name = power_group_name,
613 .attrs = runtime_attrs,
614};
615
616static struct attribute *pm_qos_resume_latency_attrs[] = {
617 &dev_attr_pm_qos_resume_latency_us.attr,
618 NULL,
619};
620static const struct attribute_group pm_qos_resume_latency_attr_group = {
621 .name = power_group_name,
622 .attrs = pm_qos_resume_latency_attrs,
623};
624
625static struct attribute *pm_qos_latency_tolerance_attrs[] = {
626 &dev_attr_pm_qos_latency_tolerance_us.attr,
627 NULL,
628};
629static const struct attribute_group pm_qos_latency_tolerance_attr_group = {
630 .name = power_group_name,
631 .attrs = pm_qos_latency_tolerance_attrs,
632};
633
634static struct attribute *pm_qos_flags_attrs[] = {
635 &dev_attr_pm_qos_no_power_off.attr,
636 NULL,
637};
638static const struct attribute_group pm_qos_flags_attr_group = {
639 .name = power_group_name,
640 .attrs = pm_qos_flags_attrs,
641};
642
643int dpm_sysfs_add(struct device *dev)
644{
645 int rc;
646
647 /* No need to create PM sysfs if explicitly disabled. */
648 if (device_pm_not_required(dev))
649 return 0;
650
651 rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
652 if (rc)
653 return rc;
654
655 if (pm_runtime_callbacks_present(dev)) {
656 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
657 if (rc)
658 goto err_out;
659 }
660 if (device_can_wakeup(dev)) {
661 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
662 if (rc)
663 goto err_runtime;
664 }
665 if (dev->power.set_latency_tolerance) {
666 rc = sysfs_merge_group(&dev->kobj,
667 &pm_qos_latency_tolerance_attr_group);
668 if (rc)
669 goto err_wakeup;
670 }
671 rc = pm_wakeup_source_sysfs_add(dev);
672 if (rc)
673 goto err_latency;
674 return 0;
675
676 err_latency:
677 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
678 err_wakeup:
679 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
680 err_runtime:
681 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
682 err_out:
683 sysfs_remove_group(&dev->kobj, &pm_attr_group);
684 return rc;
685}
686
687int wakeup_sysfs_add(struct device *dev)
688{
689 return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
690}
691
692void wakeup_sysfs_remove(struct device *dev)
693{
694 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
695}
696
697int pm_qos_sysfs_add_resume_latency(struct device *dev)
698{
699 return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
700}
701
702void pm_qos_sysfs_remove_resume_latency(struct device *dev)
703{
704 sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
705}
706
707int pm_qos_sysfs_add_flags(struct device *dev)
708{
709 return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group);
710}
711
712void pm_qos_sysfs_remove_flags(struct device *dev)
713{
714 sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
715}
716
717int pm_qos_sysfs_add_latency_tolerance(struct device *dev)
718{
719 return sysfs_merge_group(&dev->kobj,
720 &pm_qos_latency_tolerance_attr_group);
721}
722
723void pm_qos_sysfs_remove_latency_tolerance(struct device *dev)
724{
725 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
726}
727
728void rpm_sysfs_remove(struct device *dev)
729{
730 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
731}
732
733void dpm_sysfs_remove(struct device *dev)
734{
735 if (device_pm_not_required(dev))
736 return;
737 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
738 dev_pm_qos_constraints_destroy(dev);
739 rpm_sysfs_remove(dev);
740 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
741 sysfs_remove_group(&dev->kobj, &pm_attr_group);
742}
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/export.h>
8#include <linux/pm_qos.h>
9#include <linux/pm_runtime.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
95static const char enabled[] = "enabled";
96static const char disabled[] = "disabled";
97
98const char power_group_name[] = "power";
99EXPORT_SYMBOL_GPL(power_group_name);
100
101#ifdef CONFIG_PM_RUNTIME
102static const char ctrl_auto[] = "auto";
103static const char ctrl_on[] = "on";
104
105static ssize_t control_show(struct device *dev, struct device_attribute *attr,
106 char *buf)
107{
108 return sprintf(buf, "%s\n",
109 dev->power.runtime_auto ? ctrl_auto : ctrl_on);
110}
111
112static ssize_t control_store(struct device * dev, struct device_attribute *attr,
113 const char * buf, size_t n)
114{
115 char *cp;
116 int len = n;
117
118 cp = memchr(buf, '\n', n);
119 if (cp)
120 len = cp - buf;
121 device_lock(dev);
122 if (len == sizeof ctrl_auto - 1 && strncmp(buf, ctrl_auto, len) == 0)
123 pm_runtime_allow(dev);
124 else if (len == sizeof ctrl_on - 1 && strncmp(buf, ctrl_on, len) == 0)
125 pm_runtime_forbid(dev);
126 else
127 n = -EINVAL;
128 device_unlock(dev);
129 return n;
130}
131
132static DEVICE_ATTR(control, 0644, control_show, control_store);
133
134static ssize_t rtpm_active_time_show(struct device *dev,
135 struct device_attribute *attr, char *buf)
136{
137 int ret;
138 spin_lock_irq(&dev->power.lock);
139 update_pm_runtime_accounting(dev);
140 ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies));
141 spin_unlock_irq(&dev->power.lock);
142 return ret;
143}
144
145static DEVICE_ATTR(runtime_active_time, 0444, rtpm_active_time_show, NULL);
146
147static ssize_t rtpm_suspended_time_show(struct device *dev,
148 struct device_attribute *attr, char *buf)
149{
150 int ret;
151 spin_lock_irq(&dev->power.lock);
152 update_pm_runtime_accounting(dev);
153 ret = sprintf(buf, "%i\n",
154 jiffies_to_msecs(dev->power.suspended_jiffies));
155 spin_unlock_irq(&dev->power.lock);
156 return ret;
157}
158
159static DEVICE_ATTR(runtime_suspended_time, 0444, rtpm_suspended_time_show, NULL);
160
161static ssize_t rtpm_status_show(struct device *dev,
162 struct device_attribute *attr, char *buf)
163{
164 const char *p;
165
166 if (dev->power.runtime_error) {
167 p = "error\n";
168 } else if (dev->power.disable_depth) {
169 p = "unsupported\n";
170 } else {
171 switch (dev->power.runtime_status) {
172 case RPM_SUSPENDED:
173 p = "suspended\n";
174 break;
175 case RPM_SUSPENDING:
176 p = "suspending\n";
177 break;
178 case RPM_RESUMING:
179 p = "resuming\n";
180 break;
181 case RPM_ACTIVE:
182 p = "active\n";
183 break;
184 default:
185 return -EIO;
186 }
187 }
188 return sprintf(buf, p);
189}
190
191static DEVICE_ATTR(runtime_status, 0444, rtpm_status_show, NULL);
192
193static ssize_t autosuspend_delay_ms_show(struct device *dev,
194 struct device_attribute *attr, char *buf)
195{
196 if (!dev->power.use_autosuspend)
197 return -EIO;
198 return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
199}
200
201static ssize_t autosuspend_delay_ms_store(struct device *dev,
202 struct device_attribute *attr, const char *buf, size_t n)
203{
204 long delay;
205
206 if (!dev->power.use_autosuspend)
207 return -EIO;
208
209 if (strict_strtol(buf, 10, &delay) != 0 || delay != (int) delay)
210 return -EINVAL;
211
212 device_lock(dev);
213 pm_runtime_set_autosuspend_delay(dev, delay);
214 device_unlock(dev);
215 return n;
216}
217
218static DEVICE_ATTR(autosuspend_delay_ms, 0644, autosuspend_delay_ms_show,
219 autosuspend_delay_ms_store);
220
221static ssize_t pm_qos_latency_show(struct device *dev,
222 struct device_attribute *attr, char *buf)
223{
224 return sprintf(buf, "%d\n", dev->power.pq_req->node.prio);
225}
226
227static ssize_t pm_qos_latency_store(struct device *dev,
228 struct device_attribute *attr,
229 const char *buf, size_t n)
230{
231 s32 value;
232 int ret;
233
234 if (kstrtos32(buf, 0, &value))
235 return -EINVAL;
236
237 if (value < 0)
238 return -EINVAL;
239
240 ret = dev_pm_qos_update_request(dev->power.pq_req, value);
241 return ret < 0 ? ret : n;
242}
243
244static DEVICE_ATTR(pm_qos_resume_latency_us, 0644,
245 pm_qos_latency_show, pm_qos_latency_store);
246#endif /* CONFIG_PM_RUNTIME */
247
248#ifdef CONFIG_PM_SLEEP
249static ssize_t
250wake_show(struct device * dev, struct device_attribute *attr, char * buf)
251{
252 return sprintf(buf, "%s\n", device_can_wakeup(dev)
253 ? (device_may_wakeup(dev) ? enabled : disabled)
254 : "");
255}
256
257static ssize_t
258wake_store(struct device * dev, struct device_attribute *attr,
259 const char * buf, size_t n)
260{
261 char *cp;
262 int len = n;
263
264 if (!device_can_wakeup(dev))
265 return -EINVAL;
266
267 cp = memchr(buf, '\n', n);
268 if (cp)
269 len = cp - buf;
270 if (len == sizeof enabled - 1
271 && strncmp(buf, enabled, sizeof enabled - 1) == 0)
272 device_set_wakeup_enable(dev, 1);
273 else if (len == sizeof disabled - 1
274 && strncmp(buf, disabled, sizeof disabled - 1) == 0)
275 device_set_wakeup_enable(dev, 0);
276 else
277 return -EINVAL;
278 return n;
279}
280
281static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
282
283static ssize_t wakeup_count_show(struct device *dev,
284 struct device_attribute *attr, char *buf)
285{
286 unsigned long count = 0;
287 bool enabled = false;
288
289 spin_lock_irq(&dev->power.lock);
290 if (dev->power.wakeup) {
291 count = dev->power.wakeup->event_count;
292 enabled = true;
293 }
294 spin_unlock_irq(&dev->power.lock);
295 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
296}
297
298static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL);
299
300static ssize_t wakeup_active_count_show(struct device *dev,
301 struct device_attribute *attr, char *buf)
302{
303 unsigned long count = 0;
304 bool enabled = false;
305
306 spin_lock_irq(&dev->power.lock);
307 if (dev->power.wakeup) {
308 count = dev->power.wakeup->active_count;
309 enabled = true;
310 }
311 spin_unlock_irq(&dev->power.lock);
312 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
313}
314
315static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL);
316
317static ssize_t wakeup_abort_count_show(struct device *dev,
318 struct device_attribute *attr,
319 char *buf)
320{
321 unsigned long count = 0;
322 bool enabled = false;
323
324 spin_lock_irq(&dev->power.lock);
325 if (dev->power.wakeup) {
326 count = dev->power.wakeup->wakeup_count;
327 enabled = true;
328 }
329 spin_unlock_irq(&dev->power.lock);
330 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
331}
332
333static DEVICE_ATTR(wakeup_abort_count, 0444, wakeup_abort_count_show, NULL);
334
335static ssize_t wakeup_expire_count_show(struct device *dev,
336 struct device_attribute *attr,
337 char *buf)
338{
339 unsigned long count = 0;
340 bool enabled = false;
341
342 spin_lock_irq(&dev->power.lock);
343 if (dev->power.wakeup) {
344 count = dev->power.wakeup->expire_count;
345 enabled = true;
346 }
347 spin_unlock_irq(&dev->power.lock);
348 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
349}
350
351static DEVICE_ATTR(wakeup_expire_count, 0444, wakeup_expire_count_show, NULL);
352
353static ssize_t wakeup_active_show(struct device *dev,
354 struct device_attribute *attr, char *buf)
355{
356 unsigned int active = 0;
357 bool enabled = false;
358
359 spin_lock_irq(&dev->power.lock);
360 if (dev->power.wakeup) {
361 active = dev->power.wakeup->active;
362 enabled = true;
363 }
364 spin_unlock_irq(&dev->power.lock);
365 return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
366}
367
368static DEVICE_ATTR(wakeup_active, 0444, wakeup_active_show, NULL);
369
370static ssize_t wakeup_total_time_show(struct device *dev,
371 struct device_attribute *attr, char *buf)
372{
373 s64 msec = 0;
374 bool enabled = false;
375
376 spin_lock_irq(&dev->power.lock);
377 if (dev->power.wakeup) {
378 msec = ktime_to_ms(dev->power.wakeup->total_time);
379 enabled = true;
380 }
381 spin_unlock_irq(&dev->power.lock);
382 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
383}
384
385static DEVICE_ATTR(wakeup_total_time_ms, 0444, wakeup_total_time_show, NULL);
386
387static ssize_t wakeup_max_time_show(struct device *dev,
388 struct device_attribute *attr, char *buf)
389{
390 s64 msec = 0;
391 bool enabled = false;
392
393 spin_lock_irq(&dev->power.lock);
394 if (dev->power.wakeup) {
395 msec = ktime_to_ms(dev->power.wakeup->max_time);
396 enabled = true;
397 }
398 spin_unlock_irq(&dev->power.lock);
399 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
400}
401
402static DEVICE_ATTR(wakeup_max_time_ms, 0444, wakeup_max_time_show, NULL);
403
404static ssize_t wakeup_last_time_show(struct device *dev,
405 struct device_attribute *attr, char *buf)
406{
407 s64 msec = 0;
408 bool enabled = false;
409
410 spin_lock_irq(&dev->power.lock);
411 if (dev->power.wakeup) {
412 msec = ktime_to_ms(dev->power.wakeup->last_time);
413 enabled = true;
414 }
415 spin_unlock_irq(&dev->power.lock);
416 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
417}
418
419static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL);
420
421#ifdef CONFIG_PM_AUTOSLEEP
422static ssize_t wakeup_prevent_sleep_time_show(struct device *dev,
423 struct device_attribute *attr,
424 char *buf)
425{
426 s64 msec = 0;
427 bool enabled = false;
428
429 spin_lock_irq(&dev->power.lock);
430 if (dev->power.wakeup) {
431 msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
432 enabled = true;
433 }
434 spin_unlock_irq(&dev->power.lock);
435 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
436}
437
438static DEVICE_ATTR(wakeup_prevent_sleep_time_ms, 0444,
439 wakeup_prevent_sleep_time_show, NULL);
440#endif /* CONFIG_PM_AUTOSLEEP */
441#endif /* CONFIG_PM_SLEEP */
442
443#ifdef CONFIG_PM_ADVANCED_DEBUG
444#ifdef CONFIG_PM_RUNTIME
445
446static ssize_t rtpm_usagecount_show(struct device *dev,
447 struct device_attribute *attr, char *buf)
448{
449 return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
450}
451
452static ssize_t rtpm_children_show(struct device *dev,
453 struct device_attribute *attr, char *buf)
454{
455 return sprintf(buf, "%d\n", dev->power.ignore_children ?
456 0 : atomic_read(&dev->power.child_count));
457}
458
459static ssize_t rtpm_enabled_show(struct device *dev,
460 struct device_attribute *attr, char *buf)
461{
462 if ((dev->power.disable_depth) && (dev->power.runtime_auto == false))
463 return sprintf(buf, "disabled & forbidden\n");
464 else if (dev->power.disable_depth)
465 return sprintf(buf, "disabled\n");
466 else if (dev->power.runtime_auto == false)
467 return sprintf(buf, "forbidden\n");
468 return sprintf(buf, "enabled\n");
469}
470
471static DEVICE_ATTR(runtime_usage, 0444, rtpm_usagecount_show, NULL);
472static DEVICE_ATTR(runtime_active_kids, 0444, rtpm_children_show, NULL);
473static DEVICE_ATTR(runtime_enabled, 0444, rtpm_enabled_show, NULL);
474
475#endif
476
477static ssize_t async_show(struct device *dev, struct device_attribute *attr,
478 char *buf)
479{
480 return sprintf(buf, "%s\n",
481 device_async_suspend_enabled(dev) ? enabled : disabled);
482}
483
484static ssize_t async_store(struct device *dev, struct device_attribute *attr,
485 const char *buf, size_t n)
486{
487 char *cp;
488 int len = n;
489
490 cp = memchr(buf, '\n', n);
491 if (cp)
492 len = cp - buf;
493 if (len == sizeof enabled - 1 && strncmp(buf, enabled, len) == 0)
494 device_enable_async_suspend(dev);
495 else if (len == sizeof disabled - 1 && strncmp(buf, disabled, len) == 0)
496 device_disable_async_suspend(dev);
497 else
498 return -EINVAL;
499 return n;
500}
501
502static DEVICE_ATTR(async, 0644, async_show, async_store);
503#endif /* CONFIG_PM_ADVANCED_DEBUG */
504
505static struct attribute *power_attrs[] = {
506#ifdef CONFIG_PM_ADVANCED_DEBUG
507#ifdef CONFIG_PM_SLEEP
508 &dev_attr_async.attr,
509#endif
510#ifdef CONFIG_PM_RUNTIME
511 &dev_attr_runtime_status.attr,
512 &dev_attr_runtime_usage.attr,
513 &dev_attr_runtime_active_kids.attr,
514 &dev_attr_runtime_enabled.attr,
515#endif
516#endif /* CONFIG_PM_ADVANCED_DEBUG */
517 NULL,
518};
519static struct attribute_group pm_attr_group = {
520 .name = power_group_name,
521 .attrs = power_attrs,
522};
523
524static struct attribute *wakeup_attrs[] = {
525#ifdef CONFIG_PM_SLEEP
526 &dev_attr_wakeup.attr,
527 &dev_attr_wakeup_count.attr,
528 &dev_attr_wakeup_active_count.attr,
529 &dev_attr_wakeup_abort_count.attr,
530 &dev_attr_wakeup_expire_count.attr,
531 &dev_attr_wakeup_active.attr,
532 &dev_attr_wakeup_total_time_ms.attr,
533 &dev_attr_wakeup_max_time_ms.attr,
534 &dev_attr_wakeup_last_time_ms.attr,
535#ifdef CONFIG_PM_AUTOSLEEP
536 &dev_attr_wakeup_prevent_sleep_time_ms.attr,
537#endif
538#endif
539 NULL,
540};
541static struct attribute_group pm_wakeup_attr_group = {
542 .name = power_group_name,
543 .attrs = wakeup_attrs,
544};
545
546static struct attribute *runtime_attrs[] = {
547#ifdef CONFIG_PM_RUNTIME
548#ifndef CONFIG_PM_ADVANCED_DEBUG
549 &dev_attr_runtime_status.attr,
550#endif
551 &dev_attr_control.attr,
552 &dev_attr_runtime_suspended_time.attr,
553 &dev_attr_runtime_active_time.attr,
554 &dev_attr_autosuspend_delay_ms.attr,
555#endif /* CONFIG_PM_RUNTIME */
556 NULL,
557};
558static struct attribute_group pm_runtime_attr_group = {
559 .name = power_group_name,
560 .attrs = runtime_attrs,
561};
562
563static struct attribute *pm_qos_attrs[] = {
564#ifdef CONFIG_PM_RUNTIME
565 &dev_attr_pm_qos_resume_latency_us.attr,
566#endif /* CONFIG_PM_RUNTIME */
567 NULL,
568};
569static struct attribute_group pm_qos_attr_group = {
570 .name = power_group_name,
571 .attrs = pm_qos_attrs,
572};
573
574int dpm_sysfs_add(struct device *dev)
575{
576 int rc;
577
578 rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
579 if (rc)
580 return rc;
581
582 if (pm_runtime_callbacks_present(dev)) {
583 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
584 if (rc)
585 goto err_out;
586 }
587
588 if (device_can_wakeup(dev)) {
589 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
590 if (rc) {
591 if (pm_runtime_callbacks_present(dev))
592 sysfs_unmerge_group(&dev->kobj,
593 &pm_runtime_attr_group);
594 goto err_out;
595 }
596 }
597 return 0;
598
599 err_out:
600 sysfs_remove_group(&dev->kobj, &pm_attr_group);
601 return rc;
602}
603
604int wakeup_sysfs_add(struct device *dev)
605{
606 return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
607}
608
609void wakeup_sysfs_remove(struct device *dev)
610{
611 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
612}
613
614int pm_qos_sysfs_add(struct device *dev)
615{
616 return sysfs_merge_group(&dev->kobj, &pm_qos_attr_group);
617}
618
619void pm_qos_sysfs_remove(struct device *dev)
620{
621 sysfs_unmerge_group(&dev->kobj, &pm_qos_attr_group);
622}
623
624void rpm_sysfs_remove(struct device *dev)
625{
626 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
627}
628
629void dpm_sysfs_remove(struct device *dev)
630{
631 rpm_sysfs_remove(dev);
632 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
633 sysfs_remove_group(&dev->kobj, &pm_attr_group);
634}