2 * drivers/base/power/sysfs.c - sysfs entries for device PM
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>
15 * control - Report/change current runtime PM setting of the device
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:
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;
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
30 * wakeup - Report/change current wakeup option for device
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:
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.
40 * (For example, unconfigured USB devices can't issue wakeups.)
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
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.
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.
62 * async - Report/change current async suspend setting for the device
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.
69 * All devices have one of the following two values for power/async:
71 * + "enabled\n" to permit the asynchronous suspend/resume of the device;
72 * + "disabled\n" to forbid it;
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.
80 * autosuspend_delay_ms - Report/change a device's autosuspend_delay value
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
89 * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
90 * value are used only if the driver calls pm_runtime_use_autosuspend().
92 * wakeup_count - Report the number of wakeup events related to the device
95 const char power_group_name[] = "power";
96 EXPORT_SYMBOL_GPL(power_group_name);
98 static const char ctrl_auto[] = "auto";
99 static const char ctrl_on[] = "on";
101 static ssize_t control_show(struct device *dev, struct device_attribute *attr,
104 return sprintf(buf, "%s\n",
105 dev->power.runtime_auto ? ctrl_auto : ctrl_on);
108 static ssize_t control_store(struct device * dev, struct device_attribute *attr,
109 const char * buf, size_t n)
114 cp = memchr(buf, '\n', n);
118 if (len == sizeof ctrl_auto - 1 && strncmp(buf, ctrl_auto, len) == 0)
119 pm_runtime_allow(dev);
120 else if (len == sizeof ctrl_on - 1 && strncmp(buf, ctrl_on, len) == 0)
121 pm_runtime_forbid(dev);
128 static DEVICE_ATTR(control, 0644, control_show, control_store);
130 static ssize_t rtpm_active_time_show(struct device *dev,
131 struct device_attribute *attr, char *buf)
134 spin_lock_irq(&dev->power.lock);
135 update_pm_runtime_accounting(dev);
136 ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies));
137 spin_unlock_irq(&dev->power.lock);
141 static DEVICE_ATTR(runtime_active_time, 0444, rtpm_active_time_show, NULL);
143 static ssize_t rtpm_suspended_time_show(struct device *dev,
144 struct device_attribute *attr, char *buf)
147 spin_lock_irq(&dev->power.lock);
148 update_pm_runtime_accounting(dev);
149 ret = sprintf(buf, "%i\n",
150 jiffies_to_msecs(dev->power.suspended_jiffies));
151 spin_unlock_irq(&dev->power.lock);
155 static DEVICE_ATTR(runtime_suspended_time, 0444, rtpm_suspended_time_show, NULL);
157 static ssize_t rtpm_status_show(struct device *dev,
158 struct device_attribute *attr, char *buf)
162 if (dev->power.runtime_error) {
164 } else if (dev->power.disable_depth) {
167 switch (dev->power.runtime_status) {
184 return sprintf(buf, p);
187 static DEVICE_ATTR(runtime_status, 0444, rtpm_status_show, NULL);
189 static ssize_t autosuspend_delay_ms_show(struct device *dev,
190 struct device_attribute *attr, char *buf)
192 if (!dev->power.use_autosuspend)
194 return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
197 static ssize_t autosuspend_delay_ms_store(struct device *dev,
198 struct device_attribute *attr, const char *buf, size_t n)
202 if (!dev->power.use_autosuspend)
205 if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay)
209 pm_runtime_set_autosuspend_delay(dev, delay);
214 static DEVICE_ATTR(autosuspend_delay_ms, 0644, autosuspend_delay_ms_show,
215 autosuspend_delay_ms_store);
217 static ssize_t pm_qos_resume_latency_show(struct device *dev,
218 struct device_attribute *attr,
221 return sprintf(buf, "%d\n", dev_pm_qos_requested_resume_latency(dev));
224 static ssize_t pm_qos_resume_latency_store(struct device *dev,
225 struct device_attribute *attr,
226 const char *buf, size_t n)
231 if (kstrtos32(buf, 0, &value))
237 ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req,
239 return ret < 0 ? ret : n;
242 static DEVICE_ATTR(pm_qos_resume_latency_us, 0644,
243 pm_qos_resume_latency_show, pm_qos_resume_latency_store);
245 static ssize_t pm_qos_latency_tolerance_show(struct device *dev,
246 struct device_attribute *attr,
249 s32 value = dev_pm_qos_get_user_latency_tolerance(dev);
252 return sprintf(buf, "auto\n");
253 else if (value == PM_QOS_LATENCY_ANY)
254 return sprintf(buf, "any\n");
256 return sprintf(buf, "%d\n", value);
259 static ssize_t pm_qos_latency_tolerance_store(struct device *dev,
260 struct device_attribute *attr,
261 const char *buf, size_t n)
266 if (kstrtos32(buf, 0, &value)) {
267 if (!strcmp(buf, "auto") || !strcmp(buf, "auto\n"))
268 value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;
269 else if (!strcmp(buf, "any") || !strcmp(buf, "any\n"))
270 value = PM_QOS_LATENCY_ANY;
274 ret = dev_pm_qos_update_user_latency_tolerance(dev, value);
275 return ret < 0 ? ret : n;
278 static DEVICE_ATTR(pm_qos_latency_tolerance_us, 0644,
279 pm_qos_latency_tolerance_show, pm_qos_latency_tolerance_store);
281 static ssize_t pm_qos_no_power_off_show(struct device *dev,
282 struct device_attribute *attr,
285 return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
286 & PM_QOS_FLAG_NO_POWER_OFF));
289 static ssize_t pm_qos_no_power_off_store(struct device *dev,
290 struct device_attribute *attr,
291 const char *buf, size_t n)
295 if (kstrtoint(buf, 0, &ret))
298 if (ret != 0 && ret != 1)
301 ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret);
302 return ret < 0 ? ret : n;
305 static DEVICE_ATTR(pm_qos_no_power_off, 0644,
306 pm_qos_no_power_off_show, pm_qos_no_power_off_store);
308 static ssize_t pm_qos_remote_wakeup_show(struct device *dev,
309 struct device_attribute *attr,
312 return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
313 & PM_QOS_FLAG_REMOTE_WAKEUP));
316 static ssize_t pm_qos_remote_wakeup_store(struct device *dev,
317 struct device_attribute *attr,
318 const char *buf, size_t n)
322 if (kstrtoint(buf, 0, &ret))
325 if (ret != 0 && ret != 1)
328 ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP, ret);
329 return ret < 0 ? ret : n;
332 static DEVICE_ATTR(pm_qos_remote_wakeup, 0644,
333 pm_qos_remote_wakeup_show, pm_qos_remote_wakeup_store);
335 #ifdef CONFIG_PM_SLEEP
336 static const char _enabled[] = "enabled";
337 static const char _disabled[] = "disabled";
340 wake_show(struct device * dev, struct device_attribute *attr, char * buf)
342 return sprintf(buf, "%s\n", device_can_wakeup(dev)
343 ? (device_may_wakeup(dev) ? _enabled : _disabled)
348 wake_store(struct device * dev, struct device_attribute *attr,
349 const char * buf, size_t n)
354 if (!device_can_wakeup(dev))
357 cp = memchr(buf, '\n', n);
360 if (len == sizeof _enabled - 1
361 && strncmp(buf, _enabled, sizeof _enabled - 1) == 0)
362 device_set_wakeup_enable(dev, 1);
363 else if (len == sizeof _disabled - 1
364 && strncmp(buf, _disabled, sizeof _disabled - 1) == 0)
365 device_set_wakeup_enable(dev, 0);
371 static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
373 static ssize_t wakeup_count_show(struct device *dev,
374 struct device_attribute *attr, char *buf)
376 unsigned long count = 0;
377 bool enabled = false;
379 spin_lock_irq(&dev->power.lock);
380 if (dev->power.wakeup) {
381 count = dev->power.wakeup->event_count;
384 spin_unlock_irq(&dev->power.lock);
385 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
388 static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL);
390 static ssize_t wakeup_active_count_show(struct device *dev,
391 struct device_attribute *attr, char *buf)
393 unsigned long count = 0;
394 bool enabled = false;
396 spin_lock_irq(&dev->power.lock);
397 if (dev->power.wakeup) {
398 count = dev->power.wakeup->active_count;
401 spin_unlock_irq(&dev->power.lock);
402 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
405 static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL);
407 static ssize_t wakeup_abort_count_show(struct device *dev,
408 struct device_attribute *attr,
411 unsigned long count = 0;
412 bool enabled = false;
414 spin_lock_irq(&dev->power.lock);
415 if (dev->power.wakeup) {
416 count = dev->power.wakeup->wakeup_count;
419 spin_unlock_irq(&dev->power.lock);
420 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
423 static DEVICE_ATTR(wakeup_abort_count, 0444, wakeup_abort_count_show, NULL);
425 static ssize_t wakeup_expire_count_show(struct device *dev,
426 struct device_attribute *attr,
429 unsigned long count = 0;
430 bool enabled = false;
432 spin_lock_irq(&dev->power.lock);
433 if (dev->power.wakeup) {
434 count = dev->power.wakeup->expire_count;
437 spin_unlock_irq(&dev->power.lock);
438 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
441 static DEVICE_ATTR(wakeup_expire_count, 0444, wakeup_expire_count_show, NULL);
443 static ssize_t wakeup_active_show(struct device *dev,
444 struct device_attribute *attr, char *buf)
446 unsigned int active = 0;
447 bool enabled = false;
449 spin_lock_irq(&dev->power.lock);
450 if (dev->power.wakeup) {
451 active = dev->power.wakeup->active;
454 spin_unlock_irq(&dev->power.lock);
455 return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
458 static DEVICE_ATTR(wakeup_active, 0444, wakeup_active_show, NULL);
460 static ssize_t wakeup_total_time_show(struct device *dev,
461 struct device_attribute *attr, char *buf)
464 bool enabled = false;
466 spin_lock_irq(&dev->power.lock);
467 if (dev->power.wakeup) {
468 msec = ktime_to_ms(dev->power.wakeup->total_time);
471 spin_unlock_irq(&dev->power.lock);
472 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
475 static DEVICE_ATTR(wakeup_total_time_ms, 0444, wakeup_total_time_show, NULL);
477 static ssize_t wakeup_max_time_show(struct device *dev,
478 struct device_attribute *attr, char *buf)
481 bool enabled = false;
483 spin_lock_irq(&dev->power.lock);
484 if (dev->power.wakeup) {
485 msec = ktime_to_ms(dev->power.wakeup->max_time);
488 spin_unlock_irq(&dev->power.lock);
489 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
492 static DEVICE_ATTR(wakeup_max_time_ms, 0444, wakeup_max_time_show, NULL);
494 static ssize_t wakeup_last_time_show(struct device *dev,
495 struct device_attribute *attr, char *buf)
498 bool enabled = false;
500 spin_lock_irq(&dev->power.lock);
501 if (dev->power.wakeup) {
502 msec = ktime_to_ms(dev->power.wakeup->last_time);
505 spin_unlock_irq(&dev->power.lock);
506 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
509 static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL);
511 #ifdef CONFIG_PM_AUTOSLEEP
512 static ssize_t wakeup_prevent_sleep_time_show(struct device *dev,
513 struct device_attribute *attr,
517 bool enabled = false;
519 spin_lock_irq(&dev->power.lock);
520 if (dev->power.wakeup) {
521 msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
524 spin_unlock_irq(&dev->power.lock);
525 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
528 static DEVICE_ATTR(wakeup_prevent_sleep_time_ms, 0444,
529 wakeup_prevent_sleep_time_show, NULL);
530 #endif /* CONFIG_PM_AUTOSLEEP */
531 #endif /* CONFIG_PM_SLEEP */
533 #ifdef CONFIG_PM_ADVANCED_DEBUG
534 static ssize_t rtpm_usagecount_show(struct device *dev,
535 struct device_attribute *attr, char *buf)
537 return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
540 static ssize_t rtpm_children_show(struct device *dev,
541 struct device_attribute *attr, char *buf)
543 return sprintf(buf, "%d\n", dev->power.ignore_children ?
544 0 : atomic_read(&dev->power.child_count));
547 static ssize_t rtpm_enabled_show(struct device *dev,
548 struct device_attribute *attr, char *buf)
550 if ((dev->power.disable_depth) && (dev->power.runtime_auto == false))
551 return sprintf(buf, "disabled & forbidden\n");
552 else if (dev->power.disable_depth)
553 return sprintf(buf, "disabled\n");
554 else if (dev->power.runtime_auto == false)
555 return sprintf(buf, "forbidden\n");
556 return sprintf(buf, "enabled\n");
559 static DEVICE_ATTR(runtime_usage, 0444, rtpm_usagecount_show, NULL);
560 static DEVICE_ATTR(runtime_active_kids, 0444, rtpm_children_show, NULL);
561 static DEVICE_ATTR(runtime_enabled, 0444, rtpm_enabled_show, NULL);
563 #ifdef CONFIG_PM_SLEEP
564 static ssize_t async_show(struct device *dev, struct device_attribute *attr,
567 return sprintf(buf, "%s\n",
568 device_async_suspend_enabled(dev) ?
569 _enabled : _disabled);
572 static ssize_t async_store(struct device *dev, struct device_attribute *attr,
573 const char *buf, size_t n)
578 cp = memchr(buf, '\n', n);
581 if (len == sizeof _enabled - 1 && strncmp(buf, _enabled, len) == 0)
582 device_enable_async_suspend(dev);
583 else if (len == sizeof _disabled - 1 &&
584 strncmp(buf, _disabled, len) == 0)
585 device_disable_async_suspend(dev);
591 static DEVICE_ATTR(async, 0644, async_show, async_store);
593 #endif /* CONFIG_PM_SLEEP */
594 #endif /* CONFIG_PM_ADVANCED_DEBUG */
596 static struct attribute *power_attrs[] = {
597 #ifdef CONFIG_PM_ADVANCED_DEBUG
598 #ifdef CONFIG_PM_SLEEP
599 &dev_attr_async.attr,
601 &dev_attr_runtime_status.attr,
602 &dev_attr_runtime_usage.attr,
603 &dev_attr_runtime_active_kids.attr,
604 &dev_attr_runtime_enabled.attr,
605 #endif /* CONFIG_PM_ADVANCED_DEBUG */
608 static struct attribute_group pm_attr_group = {
609 .name = power_group_name,
610 .attrs = power_attrs,
613 static struct attribute *wakeup_attrs[] = {
614 #ifdef CONFIG_PM_SLEEP
615 &dev_attr_wakeup.attr,
616 &dev_attr_wakeup_count.attr,
617 &dev_attr_wakeup_active_count.attr,
618 &dev_attr_wakeup_abort_count.attr,
619 &dev_attr_wakeup_expire_count.attr,
620 &dev_attr_wakeup_active.attr,
621 &dev_attr_wakeup_total_time_ms.attr,
622 &dev_attr_wakeup_max_time_ms.attr,
623 &dev_attr_wakeup_last_time_ms.attr,
624 #ifdef CONFIG_PM_AUTOSLEEP
625 &dev_attr_wakeup_prevent_sleep_time_ms.attr,
630 static struct attribute_group pm_wakeup_attr_group = {
631 .name = power_group_name,
632 .attrs = wakeup_attrs,
635 static struct attribute *runtime_attrs[] = {
636 #ifndef CONFIG_PM_ADVANCED_DEBUG
637 &dev_attr_runtime_status.attr,
639 &dev_attr_control.attr,
640 &dev_attr_runtime_suspended_time.attr,
641 &dev_attr_runtime_active_time.attr,
642 &dev_attr_autosuspend_delay_ms.attr,
645 static struct attribute_group pm_runtime_attr_group = {
646 .name = power_group_name,
647 .attrs = runtime_attrs,
650 static struct attribute *pm_qos_resume_latency_attrs[] = {
651 &dev_attr_pm_qos_resume_latency_us.attr,
654 static struct attribute_group pm_qos_resume_latency_attr_group = {
655 .name = power_group_name,
656 .attrs = pm_qos_resume_latency_attrs,
659 static struct attribute *pm_qos_latency_tolerance_attrs[] = {
660 &dev_attr_pm_qos_latency_tolerance_us.attr,
663 static struct attribute_group pm_qos_latency_tolerance_attr_group = {
664 .name = power_group_name,
665 .attrs = pm_qos_latency_tolerance_attrs,
668 static struct attribute *pm_qos_flags_attrs[] = {
669 &dev_attr_pm_qos_no_power_off.attr,
670 &dev_attr_pm_qos_remote_wakeup.attr,
673 static struct attribute_group pm_qos_flags_attr_group = {
674 .name = power_group_name,
675 .attrs = pm_qos_flags_attrs,
678 int dpm_sysfs_add(struct device *dev)
682 rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
686 if (pm_runtime_callbacks_present(dev)) {
687 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
691 if (device_can_wakeup(dev)) {
692 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
696 if (dev->power.set_latency_tolerance) {
697 rc = sysfs_merge_group(&dev->kobj,
698 &pm_qos_latency_tolerance_attr_group);
705 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
707 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
709 sysfs_remove_group(&dev->kobj, &pm_attr_group);
713 int wakeup_sysfs_add(struct device *dev)
715 return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
718 void wakeup_sysfs_remove(struct device *dev)
720 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
723 int pm_qos_sysfs_add_resume_latency(struct device *dev)
725 return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
728 void pm_qos_sysfs_remove_resume_latency(struct device *dev)
730 sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
733 int pm_qos_sysfs_add_flags(struct device *dev)
735 return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group);
738 void pm_qos_sysfs_remove_flags(struct device *dev)
740 sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
743 int pm_qos_sysfs_add_latency_tolerance(struct device *dev)
745 return sysfs_merge_group(&dev->kobj,
746 &pm_qos_latency_tolerance_attr_group);
749 void pm_qos_sysfs_remove_latency_tolerance(struct device *dev)
751 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
754 void rpm_sysfs_remove(struct device *dev)
756 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
759 void dpm_sysfs_remove(struct device *dev)
761 sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
762 dev_pm_qos_constraints_destroy(dev);
763 rpm_sysfs_remove(dev);
764 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
765 sysfs_remove_group(&dev->kobj, &pm_attr_group);