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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/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}