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>
14 * control - Report/change current runtime PM setting of the device
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:
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;
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
29 * wakeup - Report/change current wakeup option for device
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:
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.
39 * (For example, unconfigured USB devices can't issue wakeups.)
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
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.
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.
61 * async - Report/change current async suspend setting for the device
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.
68 * All devices have one of the following two values for power/async:
70 * + "enabled\n" to permit the asynchronous suspend/resume of the device;
71 * + "disabled\n" to forbid it;
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.
79 * autosuspend_delay_ms - Report/change a device's autosuspend_delay value
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
88 * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
89 * value are used only if the driver calls pm_runtime_use_autosuspend().
91 * wakeup_count - Report the number of wakeup events related to the device
94 const char power_group_name[] = "power";
95 EXPORT_SYMBOL_GPL(power_group_name);
97 static const char ctrl_auto[] = "auto";
98 static const char ctrl_on[] = "on";
100 static ssize_t control_show(struct device *dev, struct device_attribute *attr,
103 return sprintf(buf, "%s\n",
104 dev->power.runtime_auto ? ctrl_auto : ctrl_on);
107 static ssize_t control_store(struct device * dev, struct device_attribute *attr,
108 const char * buf, size_t n)
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);
121 static DEVICE_ATTR_RW(control);
123 static ssize_t runtime_active_time_show(struct device *dev,
124 struct device_attribute *attr, char *buf)
127 u64 tmp = pm_runtime_active_time(dev);
128 do_div(tmp, NSEC_PER_MSEC);
129 ret = sprintf(buf, "%llu\n", tmp);
133 static DEVICE_ATTR_RO(runtime_active_time);
135 static ssize_t runtime_suspended_time_show(struct device *dev,
136 struct device_attribute *attr, char *buf)
139 u64 tmp = pm_runtime_suspended_time(dev);
140 do_div(tmp, NSEC_PER_MSEC);
141 ret = sprintf(buf, "%llu\n", tmp);
145 static DEVICE_ATTR_RO(runtime_suspended_time);
147 static ssize_t runtime_status_show(struct device *dev,
148 struct device_attribute *attr, char *buf)
152 if (dev->power.runtime_error) {
154 } else if (dev->power.disable_depth) {
157 switch (dev->power.runtime_status) {
174 return sprintf(buf, p);
177 static DEVICE_ATTR_RO(runtime_status);
179 static ssize_t autosuspend_delay_ms_show(struct device *dev,
180 struct device_attribute *attr, char *buf)
182 if (!dev->power.use_autosuspend)
184 return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
187 static ssize_t autosuspend_delay_ms_store(struct device *dev,
188 struct device_attribute *attr, const char *buf, size_t n)
192 if (!dev->power.use_autosuspend)
195 if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay)
199 pm_runtime_set_autosuspend_delay(dev, delay);
204 static DEVICE_ATTR_RW(autosuspend_delay_ms);
206 static ssize_t pm_qos_resume_latency_us_show(struct device *dev,
207 struct device_attribute *attr,
210 s32 value = dev_pm_qos_requested_resume_latency(dev);
213 return sprintf(buf, "n/a\n");
214 if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
217 return sprintf(buf, "%d\n", value);
220 static ssize_t pm_qos_resume_latency_us_store(struct device *dev,
221 struct device_attribute *attr,
222 const char *buf, size_t n)
227 if (!kstrtos32(buf, 0, &value)) {
229 * Prevent users from writing negative or "no constraint" values
232 if (value < 0 || value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
236 value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
237 } else if (sysfs_streq(buf, "n/a")) {
243 ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req,
245 return ret < 0 ? ret : n;
248 static DEVICE_ATTR_RW(pm_qos_resume_latency_us);
250 static ssize_t pm_qos_latency_tolerance_us_show(struct device *dev,
251 struct device_attribute *attr,
254 s32 value = dev_pm_qos_get_user_latency_tolerance(dev);
257 return sprintf(buf, "auto\n");
258 if (value == PM_QOS_LATENCY_ANY)
259 return sprintf(buf, "any\n");
261 return sprintf(buf, "%d\n", value);
264 static ssize_t pm_qos_latency_tolerance_us_store(struct device *dev,
265 struct device_attribute *attr,
266 const char *buf, size_t n)
271 if (kstrtos32(buf, 0, &value) == 0) {
272 /* Users can't write negative values directly */
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;
283 ret = dev_pm_qos_update_user_latency_tolerance(dev, value);
284 return ret < 0 ? ret : n;
287 static DEVICE_ATTR_RW(pm_qos_latency_tolerance_us);
289 static ssize_t pm_qos_no_power_off_show(struct device *dev,
290 struct device_attribute *attr,
293 return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
294 & PM_QOS_FLAG_NO_POWER_OFF));
297 static ssize_t pm_qos_no_power_off_store(struct device *dev,
298 struct device_attribute *attr,
299 const char *buf, size_t n)
303 if (kstrtoint(buf, 0, &ret))
306 if (ret != 0 && ret != 1)
309 ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret);
310 return ret < 0 ? ret : n;
313 static DEVICE_ATTR_RW(pm_qos_no_power_off);
315 #ifdef CONFIG_PM_SLEEP
316 static const char _enabled[] = "enabled";
317 static const char _disabled[] = "disabled";
319 static ssize_t wakeup_show(struct device *dev, struct device_attribute *attr,
322 return sprintf(buf, "%s\n", device_can_wakeup(dev)
323 ? (device_may_wakeup(dev) ? _enabled : _disabled)
327 static ssize_t wakeup_store(struct device *dev, struct device_attribute *attr,
328 const char *buf, size_t n)
330 if (!device_can_wakeup(dev))
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);
342 static DEVICE_ATTR_RW(wakeup);
344 static ssize_t wakeup_count_show(struct device *dev,
345 struct device_attribute *attr, char *buf)
347 unsigned long count = 0;
348 bool enabled = false;
350 spin_lock_irq(&dev->power.lock);
351 if (dev->power.wakeup) {
352 count = dev->power.wakeup->wakeup_count;
355 spin_unlock_irq(&dev->power.lock);
356 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
359 static DEVICE_ATTR_RO(wakeup_count);
361 static ssize_t wakeup_active_count_show(struct device *dev,
362 struct device_attribute *attr,
365 unsigned long count = 0;
366 bool enabled = false;
368 spin_lock_irq(&dev->power.lock);
369 if (dev->power.wakeup) {
370 count = dev->power.wakeup->active_count;
373 spin_unlock_irq(&dev->power.lock);
374 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
377 static DEVICE_ATTR_RO(wakeup_active_count);
379 static ssize_t wakeup_abort_count_show(struct device *dev,
380 struct device_attribute *attr,
383 unsigned long count = 0;
384 bool enabled = false;
386 spin_lock_irq(&dev->power.lock);
387 if (dev->power.wakeup) {
388 count = dev->power.wakeup->wakeup_count;
391 spin_unlock_irq(&dev->power.lock);
392 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
395 static DEVICE_ATTR_RO(wakeup_abort_count);
397 static ssize_t wakeup_expire_count_show(struct device *dev,
398 struct device_attribute *attr,
401 unsigned long count = 0;
402 bool enabled = false;
404 spin_lock_irq(&dev->power.lock);
405 if (dev->power.wakeup) {
406 count = dev->power.wakeup->expire_count;
409 spin_unlock_irq(&dev->power.lock);
410 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
413 static DEVICE_ATTR_RO(wakeup_expire_count);
415 static ssize_t wakeup_active_show(struct device *dev,
416 struct device_attribute *attr, char *buf)
418 unsigned int active = 0;
419 bool enabled = false;
421 spin_lock_irq(&dev->power.lock);
422 if (dev->power.wakeup) {
423 active = dev->power.wakeup->active;
426 spin_unlock_irq(&dev->power.lock);
427 return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
430 static DEVICE_ATTR_RO(wakeup_active);
432 static ssize_t wakeup_total_time_ms_show(struct device *dev,
433 struct device_attribute *attr,
437 bool enabled = false;
439 spin_lock_irq(&dev->power.lock);
440 if (dev->power.wakeup) {
441 msec = ktime_to_ms(dev->power.wakeup->total_time);
444 spin_unlock_irq(&dev->power.lock);
445 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
448 static DEVICE_ATTR_RO(wakeup_total_time_ms);
450 static ssize_t wakeup_max_time_ms_show(struct device *dev,
451 struct device_attribute *attr, char *buf)
454 bool enabled = false;
456 spin_lock_irq(&dev->power.lock);
457 if (dev->power.wakeup) {
458 msec = ktime_to_ms(dev->power.wakeup->max_time);
461 spin_unlock_irq(&dev->power.lock);
462 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
465 static DEVICE_ATTR_RO(wakeup_max_time_ms);
467 static ssize_t wakeup_last_time_ms_show(struct device *dev,
468 struct device_attribute *attr,
472 bool enabled = false;
474 spin_lock_irq(&dev->power.lock);
475 if (dev->power.wakeup) {
476 msec = ktime_to_ms(dev->power.wakeup->last_time);
479 spin_unlock_irq(&dev->power.lock);
480 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
483 static DEVICE_ATTR_RO(wakeup_last_time_ms);
485 #ifdef CONFIG_PM_AUTOSLEEP
486 static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev,
487 struct device_attribute *attr,
491 bool enabled = false;
493 spin_lock_irq(&dev->power.lock);
494 if (dev->power.wakeup) {
495 msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
498 spin_unlock_irq(&dev->power.lock);
499 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
502 static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms);
503 #endif /* CONFIG_PM_AUTOSLEEP */
504 #endif /* CONFIG_PM_SLEEP */
506 #ifdef CONFIG_PM_ADVANCED_DEBUG
507 static ssize_t runtime_usage_show(struct device *dev,
508 struct device_attribute *attr, char *buf)
510 return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
512 static DEVICE_ATTR_RO(runtime_usage);
514 static ssize_t runtime_active_kids_show(struct device *dev,
515 struct device_attribute *attr,
518 return sprintf(buf, "%d\n", dev->power.ignore_children ?
519 0 : atomic_read(&dev->power.child_count));
521 static DEVICE_ATTR_RO(runtime_active_kids);
523 static ssize_t runtime_enabled_show(struct device *dev,
524 struct device_attribute *attr, char *buf)
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");
534 static DEVICE_ATTR_RO(runtime_enabled);
536 #ifdef CONFIG_PM_SLEEP
537 static ssize_t async_show(struct device *dev, struct device_attribute *attr,
540 return sprintf(buf, "%s\n",
541 device_async_suspend_enabled(dev) ?
542 _enabled : _disabled);
545 static ssize_t async_store(struct device *dev, struct device_attribute *attr,
546 const char *buf, size_t n)
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);
557 static DEVICE_ATTR_RW(async);
559 #endif /* CONFIG_PM_SLEEP */
560 #endif /* CONFIG_PM_ADVANCED_DEBUG */
562 static struct attribute *power_attrs[] = {
563 #ifdef CONFIG_PM_ADVANCED_DEBUG
564 #ifdef CONFIG_PM_SLEEP
565 &dev_attr_async.attr,
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 */
574 static const struct attribute_group pm_attr_group = {
575 .name = power_group_name,
576 .attrs = power_attrs,
579 static 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,
596 static const struct attribute_group pm_wakeup_attr_group = {
597 .name = power_group_name,
598 .attrs = wakeup_attrs,
601 static struct attribute *runtime_attrs[] = {
602 #ifndef CONFIG_PM_ADVANCED_DEBUG
603 &dev_attr_runtime_status.attr,
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,
611 static const struct attribute_group pm_runtime_attr_group = {
612 .name = power_group_name,
613 .attrs = runtime_attrs,
616 static struct attribute *pm_qos_resume_latency_attrs[] = {
617 &dev_attr_pm_qos_resume_latency_us.attr,
620 static const struct attribute_group pm_qos_resume_latency_attr_group = {
621 .name = power_group_name,
622 .attrs = pm_qos_resume_latency_attrs,
625 static struct attribute *pm_qos_latency_tolerance_attrs[] = {
626 &dev_attr_pm_qos_latency_tolerance_us.attr,
629 static const struct attribute_group pm_qos_latency_tolerance_attr_group = {
630 .name = power_group_name,
631 .attrs = pm_qos_latency_tolerance_attrs,
634 static struct attribute *pm_qos_flags_attrs[] = {
635 &dev_attr_pm_qos_no_power_off.attr,
638 static const struct attribute_group pm_qos_flags_attr_group = {
639 .name = power_group_name,
640 .attrs = pm_qos_flags_attrs,
643 int dpm_sysfs_add(struct device *dev)
647 /* No need to create PM sysfs if explicitly disabled. */
648 if (device_pm_not_required(dev))
651 rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
655 if (pm_runtime_callbacks_present(dev)) {
656 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
660 if (device_can_wakeup(dev)) {
661 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
665 if (dev->power.set_latency_tolerance) {
666 rc = sysfs_merge_group(&dev->kobj,
667 &pm_qos_latency_tolerance_attr_group);
671 rc = pm_wakeup_source_sysfs_add(dev);
677 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
679 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
681 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
683 sysfs_remove_group(&dev->kobj, &pm_attr_group);
687 int wakeup_sysfs_add(struct device *dev)
689 return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
692 void wakeup_sysfs_remove(struct device *dev)
694 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
697 int pm_qos_sysfs_add_resume_latency(struct device *dev)
699 return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
702 void pm_qos_sysfs_remove_resume_latency(struct device *dev)
704 sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
707 int pm_qos_sysfs_add_flags(struct device *dev)
709 return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group);
712 void pm_qos_sysfs_remove_flags(struct device *dev)
714 sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
717 int pm_qos_sysfs_add_latency_tolerance(struct device *dev)
719 return sysfs_merge_group(&dev->kobj,
720 &pm_qos_latency_tolerance_attr_group);
723 void pm_qos_sysfs_remove_latency_tolerance(struct device *dev)
725 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
728 void rpm_sysfs_remove(struct device *dev)
730 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
733 void dpm_sysfs_remove(struct device *dev)
735 if (device_pm_not_required(dev))
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);