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 static const char enabled
[] = "enabled";
96 static const char disabled
[] = "disabled";
98 const char power_group_name
[] = "power";
99 EXPORT_SYMBOL_GPL(power_group_name
);
101 #ifdef CONFIG_PM_RUNTIME
102 static const char ctrl_auto
[] = "auto";
103 static const char ctrl_on
[] = "on";
105 static ssize_t
control_show(struct device
*dev
, struct device_attribute
*attr
,
108 return sprintf(buf
, "%s\n",
109 dev
->power
.runtime_auto
? ctrl_auto
: ctrl_on
);
112 static ssize_t
control_store(struct device
* dev
, struct device_attribute
*attr
,
113 const char * buf
, size_t n
)
118 cp
= memchr(buf
, '\n', n
);
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
);
132 static DEVICE_ATTR(control
, 0644, control_show
, control_store
);
134 static ssize_t
rtpm_active_time_show(struct device
*dev
,
135 struct device_attribute
*attr
, char *buf
)
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
);
145 static DEVICE_ATTR(runtime_active_time
, 0444, rtpm_active_time_show
, NULL
);
147 static ssize_t
rtpm_suspended_time_show(struct device
*dev
,
148 struct device_attribute
*attr
, char *buf
)
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
);
159 static DEVICE_ATTR(runtime_suspended_time
, 0444, rtpm_suspended_time_show
, NULL
);
161 static ssize_t
rtpm_status_show(struct device
*dev
,
162 struct device_attribute
*attr
, char *buf
)
166 if (dev
->power
.runtime_error
) {
168 } else if (dev
->power
.disable_depth
) {
171 switch (dev
->power
.runtime_status
) {
188 return sprintf(buf
, p
);
191 static DEVICE_ATTR(runtime_status
, 0444, rtpm_status_show
, NULL
);
193 static ssize_t
autosuspend_delay_ms_show(struct device
*dev
,
194 struct device_attribute
*attr
, char *buf
)
196 if (!dev
->power
.use_autosuspend
)
198 return sprintf(buf
, "%d\n", dev
->power
.autosuspend_delay
);
201 static ssize_t
autosuspend_delay_ms_store(struct device
*dev
,
202 struct device_attribute
*attr
, const char *buf
, size_t n
)
206 if (!dev
->power
.use_autosuspend
)
209 if (kstrtol(buf
, 10, &delay
) != 0 || delay
!= (int) delay
)
213 pm_runtime_set_autosuspend_delay(dev
, delay
);
218 static DEVICE_ATTR(autosuspend_delay_ms
, 0644, autosuspend_delay_ms_show
,
219 autosuspend_delay_ms_store
);
221 static ssize_t
pm_qos_latency_show(struct device
*dev
,
222 struct device_attribute
*attr
, char *buf
)
224 return sprintf(buf
, "%d\n", dev_pm_qos_requested_latency(dev
));
227 static ssize_t
pm_qos_latency_store(struct device
*dev
,
228 struct device_attribute
*attr
,
229 const char *buf
, size_t n
)
234 if (kstrtos32(buf
, 0, &value
))
240 ret
= dev_pm_qos_update_request(dev
->power
.qos
->latency_req
, value
);
241 return ret
< 0 ? ret
: n
;
244 static DEVICE_ATTR(pm_qos_resume_latency_us
, 0644,
245 pm_qos_latency_show
, pm_qos_latency_store
);
247 static ssize_t
pm_qos_no_power_off_show(struct device
*dev
,
248 struct device_attribute
*attr
,
251 return sprintf(buf
, "%d\n", !!(dev_pm_qos_requested_flags(dev
)
252 & PM_QOS_FLAG_NO_POWER_OFF
));
255 static ssize_t
pm_qos_no_power_off_store(struct device
*dev
,
256 struct device_attribute
*attr
,
257 const char *buf
, size_t n
)
261 if (kstrtoint(buf
, 0, &ret
))
264 if (ret
!= 0 && ret
!= 1)
267 ret
= dev_pm_qos_update_flags(dev
, PM_QOS_FLAG_NO_POWER_OFF
, ret
);
268 return ret
< 0 ? ret
: n
;
271 static DEVICE_ATTR(pm_qos_no_power_off
, 0644,
272 pm_qos_no_power_off_show
, pm_qos_no_power_off_store
);
274 static ssize_t
pm_qos_remote_wakeup_show(struct device
*dev
,
275 struct device_attribute
*attr
,
278 return sprintf(buf
, "%d\n", !!(dev_pm_qos_requested_flags(dev
)
279 & PM_QOS_FLAG_REMOTE_WAKEUP
));
282 static ssize_t
pm_qos_remote_wakeup_store(struct device
*dev
,
283 struct device_attribute
*attr
,
284 const char *buf
, size_t n
)
288 if (kstrtoint(buf
, 0, &ret
))
291 if (ret
!= 0 && ret
!= 1)
294 ret
= dev_pm_qos_update_flags(dev
, PM_QOS_FLAG_REMOTE_WAKEUP
, ret
);
295 return ret
< 0 ? ret
: n
;
298 static DEVICE_ATTR(pm_qos_remote_wakeup
, 0644,
299 pm_qos_remote_wakeup_show
, pm_qos_remote_wakeup_store
);
300 #endif /* CONFIG_PM_RUNTIME */
302 #ifdef CONFIG_PM_SLEEP
304 wake_show(struct device
* dev
, struct device_attribute
*attr
, char * buf
)
306 return sprintf(buf
, "%s\n", device_can_wakeup(dev
)
307 ? (device_may_wakeup(dev
) ? enabled
: disabled
)
312 wake_store(struct device
* dev
, struct device_attribute
*attr
,
313 const char * buf
, size_t n
)
318 if (!device_can_wakeup(dev
))
321 cp
= memchr(buf
, '\n', n
);
324 if (len
== sizeof enabled
- 1
325 && strncmp(buf
, enabled
, sizeof enabled
- 1) == 0)
326 device_set_wakeup_enable(dev
, 1);
327 else if (len
== sizeof disabled
- 1
328 && strncmp(buf
, disabled
, sizeof disabled
- 1) == 0)
329 device_set_wakeup_enable(dev
, 0);
335 static DEVICE_ATTR(wakeup
, 0644, wake_show
, wake_store
);
337 static ssize_t
wakeup_count_show(struct device
*dev
,
338 struct device_attribute
*attr
, char *buf
)
340 unsigned long count
= 0;
341 bool enabled
= false;
343 spin_lock_irq(&dev
->power
.lock
);
344 if (dev
->power
.wakeup
) {
345 count
= dev
->power
.wakeup
->event_count
;
348 spin_unlock_irq(&dev
->power
.lock
);
349 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
352 static DEVICE_ATTR(wakeup_count
, 0444, wakeup_count_show
, NULL
);
354 static ssize_t
wakeup_active_count_show(struct device
*dev
,
355 struct device_attribute
*attr
, char *buf
)
357 unsigned long count
= 0;
358 bool enabled
= false;
360 spin_lock_irq(&dev
->power
.lock
);
361 if (dev
->power
.wakeup
) {
362 count
= dev
->power
.wakeup
->active_count
;
365 spin_unlock_irq(&dev
->power
.lock
);
366 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
369 static DEVICE_ATTR(wakeup_active_count
, 0444, wakeup_active_count_show
, NULL
);
371 static ssize_t
wakeup_abort_count_show(struct device
*dev
,
372 struct device_attribute
*attr
,
375 unsigned long count
= 0;
376 bool enabled
= false;
378 spin_lock_irq(&dev
->power
.lock
);
379 if (dev
->power
.wakeup
) {
380 count
= dev
->power
.wakeup
->wakeup_count
;
383 spin_unlock_irq(&dev
->power
.lock
);
384 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
387 static DEVICE_ATTR(wakeup_abort_count
, 0444, wakeup_abort_count_show
, NULL
);
389 static ssize_t
wakeup_expire_count_show(struct device
*dev
,
390 struct device_attribute
*attr
,
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
->expire_count
;
401 spin_unlock_irq(&dev
->power
.lock
);
402 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
405 static DEVICE_ATTR(wakeup_expire_count
, 0444, wakeup_expire_count_show
, NULL
);
407 static ssize_t
wakeup_active_show(struct device
*dev
,
408 struct device_attribute
*attr
, char *buf
)
410 unsigned int active
= 0;
411 bool enabled
= false;
413 spin_lock_irq(&dev
->power
.lock
);
414 if (dev
->power
.wakeup
) {
415 active
= dev
->power
.wakeup
->active
;
418 spin_unlock_irq(&dev
->power
.lock
);
419 return enabled
? sprintf(buf
, "%u\n", active
) : sprintf(buf
, "\n");
422 static DEVICE_ATTR(wakeup_active
, 0444, wakeup_active_show
, NULL
);
424 static ssize_t
wakeup_total_time_show(struct device
*dev
,
425 struct device_attribute
*attr
, char *buf
)
428 bool enabled
= false;
430 spin_lock_irq(&dev
->power
.lock
);
431 if (dev
->power
.wakeup
) {
432 msec
= ktime_to_ms(dev
->power
.wakeup
->total_time
);
435 spin_unlock_irq(&dev
->power
.lock
);
436 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
439 static DEVICE_ATTR(wakeup_total_time_ms
, 0444, wakeup_total_time_show
, NULL
);
441 static ssize_t
wakeup_max_time_show(struct device
*dev
,
442 struct device_attribute
*attr
, char *buf
)
445 bool enabled
= false;
447 spin_lock_irq(&dev
->power
.lock
);
448 if (dev
->power
.wakeup
) {
449 msec
= ktime_to_ms(dev
->power
.wakeup
->max_time
);
452 spin_unlock_irq(&dev
->power
.lock
);
453 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
456 static DEVICE_ATTR(wakeup_max_time_ms
, 0444, wakeup_max_time_show
, NULL
);
458 static ssize_t
wakeup_last_time_show(struct device
*dev
,
459 struct device_attribute
*attr
, char *buf
)
462 bool enabled
= false;
464 spin_lock_irq(&dev
->power
.lock
);
465 if (dev
->power
.wakeup
) {
466 msec
= ktime_to_ms(dev
->power
.wakeup
->last_time
);
469 spin_unlock_irq(&dev
->power
.lock
);
470 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
473 static DEVICE_ATTR(wakeup_last_time_ms
, 0444, wakeup_last_time_show
, NULL
);
475 #ifdef CONFIG_PM_AUTOSLEEP
476 static ssize_t
wakeup_prevent_sleep_time_show(struct device
*dev
,
477 struct device_attribute
*attr
,
481 bool enabled
= false;
483 spin_lock_irq(&dev
->power
.lock
);
484 if (dev
->power
.wakeup
) {
485 msec
= ktime_to_ms(dev
->power
.wakeup
->prevent_sleep_time
);
488 spin_unlock_irq(&dev
->power
.lock
);
489 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
492 static DEVICE_ATTR(wakeup_prevent_sleep_time_ms
, 0444,
493 wakeup_prevent_sleep_time_show
, NULL
);
494 #endif /* CONFIG_PM_AUTOSLEEP */
495 #endif /* CONFIG_PM_SLEEP */
497 #ifdef CONFIG_PM_ADVANCED_DEBUG
498 #ifdef CONFIG_PM_RUNTIME
500 static ssize_t
rtpm_usagecount_show(struct device
*dev
,
501 struct device_attribute
*attr
, char *buf
)
503 return sprintf(buf
, "%d\n", atomic_read(&dev
->power
.usage_count
));
506 static ssize_t
rtpm_children_show(struct device
*dev
,
507 struct device_attribute
*attr
, char *buf
)
509 return sprintf(buf
, "%d\n", dev
->power
.ignore_children
?
510 0 : atomic_read(&dev
->power
.child_count
));
513 static ssize_t
rtpm_enabled_show(struct device
*dev
,
514 struct device_attribute
*attr
, char *buf
)
516 if ((dev
->power
.disable_depth
) && (dev
->power
.runtime_auto
== false))
517 return sprintf(buf
, "disabled & forbidden\n");
518 else if (dev
->power
.disable_depth
)
519 return sprintf(buf
, "disabled\n");
520 else if (dev
->power
.runtime_auto
== false)
521 return sprintf(buf
, "forbidden\n");
522 return sprintf(buf
, "enabled\n");
525 static DEVICE_ATTR(runtime_usage
, 0444, rtpm_usagecount_show
, NULL
);
526 static DEVICE_ATTR(runtime_active_kids
, 0444, rtpm_children_show
, NULL
);
527 static DEVICE_ATTR(runtime_enabled
, 0444, rtpm_enabled_show
, NULL
);
531 #ifdef CONFIG_PM_SLEEP
533 static ssize_t
async_show(struct device
*dev
, struct device_attribute
*attr
,
536 return sprintf(buf
, "%s\n",
537 device_async_suspend_enabled(dev
) ? enabled
: disabled
);
540 static ssize_t
async_store(struct device
*dev
, struct device_attribute
*attr
,
541 const char *buf
, size_t n
)
546 cp
= memchr(buf
, '\n', n
);
549 if (len
== sizeof enabled
- 1 && strncmp(buf
, enabled
, len
) == 0)
550 device_enable_async_suspend(dev
);
551 else if (len
== sizeof disabled
- 1 && strncmp(buf
, disabled
, len
) == 0)
552 device_disable_async_suspend(dev
);
558 static DEVICE_ATTR(async
, 0644, async_show
, async_store
);
561 #endif /* CONFIG_PM_ADVANCED_DEBUG */
563 static struct attribute
*power_attrs
[] = {
564 #ifdef CONFIG_PM_ADVANCED_DEBUG
565 #ifdef CONFIG_PM_SLEEP
566 &dev_attr_async
.attr
,
568 #ifdef CONFIG_PM_RUNTIME
569 &dev_attr_runtime_status
.attr
,
570 &dev_attr_runtime_usage
.attr
,
571 &dev_attr_runtime_active_kids
.attr
,
572 &dev_attr_runtime_enabled
.attr
,
574 #endif /* CONFIG_PM_ADVANCED_DEBUG */
577 static struct attribute_group pm_attr_group
= {
578 .name
= power_group_name
,
579 .attrs
= power_attrs
,
582 static struct attribute
*wakeup_attrs
[] = {
583 #ifdef CONFIG_PM_SLEEP
584 &dev_attr_wakeup
.attr
,
585 &dev_attr_wakeup_count
.attr
,
586 &dev_attr_wakeup_active_count
.attr
,
587 &dev_attr_wakeup_abort_count
.attr
,
588 &dev_attr_wakeup_expire_count
.attr
,
589 &dev_attr_wakeup_active
.attr
,
590 &dev_attr_wakeup_total_time_ms
.attr
,
591 &dev_attr_wakeup_max_time_ms
.attr
,
592 &dev_attr_wakeup_last_time_ms
.attr
,
593 #ifdef CONFIG_PM_AUTOSLEEP
594 &dev_attr_wakeup_prevent_sleep_time_ms
.attr
,
599 static struct attribute_group pm_wakeup_attr_group
= {
600 .name
= power_group_name
,
601 .attrs
= wakeup_attrs
,
604 static struct attribute
*runtime_attrs
[] = {
605 #ifdef CONFIG_PM_RUNTIME
606 #ifndef CONFIG_PM_ADVANCED_DEBUG
607 &dev_attr_runtime_status
.attr
,
609 &dev_attr_control
.attr
,
610 &dev_attr_runtime_suspended_time
.attr
,
611 &dev_attr_runtime_active_time
.attr
,
612 &dev_attr_autosuspend_delay_ms
.attr
,
613 #endif /* CONFIG_PM_RUNTIME */
616 static struct attribute_group pm_runtime_attr_group
= {
617 .name
= power_group_name
,
618 .attrs
= runtime_attrs
,
621 static struct attribute
*pm_qos_latency_attrs
[] = {
622 #ifdef CONFIG_PM_RUNTIME
623 &dev_attr_pm_qos_resume_latency_us
.attr
,
624 #endif /* CONFIG_PM_RUNTIME */
627 static struct attribute_group pm_qos_latency_attr_group
= {
628 .name
= power_group_name
,
629 .attrs
= pm_qos_latency_attrs
,
632 static struct attribute
*pm_qos_flags_attrs
[] = {
633 #ifdef CONFIG_PM_RUNTIME
634 &dev_attr_pm_qos_no_power_off
.attr
,
635 &dev_attr_pm_qos_remote_wakeup
.attr
,
636 #endif /* CONFIG_PM_RUNTIME */
639 static struct attribute_group pm_qos_flags_attr_group
= {
640 .name
= power_group_name
,
641 .attrs
= pm_qos_flags_attrs
,
644 int dpm_sysfs_add(struct device
*dev
)
648 rc
= sysfs_create_group(&dev
->kobj
, &pm_attr_group
);
652 if (pm_runtime_callbacks_present(dev
)) {
653 rc
= sysfs_merge_group(&dev
->kobj
, &pm_runtime_attr_group
);
658 if (device_can_wakeup(dev
)) {
659 rc
= sysfs_merge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
661 if (pm_runtime_callbacks_present(dev
))
662 sysfs_unmerge_group(&dev
->kobj
,
663 &pm_runtime_attr_group
);
670 sysfs_remove_group(&dev
->kobj
, &pm_attr_group
);
674 int wakeup_sysfs_add(struct device
*dev
)
676 return sysfs_merge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
679 void wakeup_sysfs_remove(struct device
*dev
)
681 sysfs_unmerge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
684 int pm_qos_sysfs_add_latency(struct device
*dev
)
686 return sysfs_merge_group(&dev
->kobj
, &pm_qos_latency_attr_group
);
689 void pm_qos_sysfs_remove_latency(struct device
*dev
)
691 sysfs_unmerge_group(&dev
->kobj
, &pm_qos_latency_attr_group
);
694 int pm_qos_sysfs_add_flags(struct device
*dev
)
696 return sysfs_merge_group(&dev
->kobj
, &pm_qos_flags_attr_group
);
699 void pm_qos_sysfs_remove_flags(struct device
*dev
)
701 sysfs_unmerge_group(&dev
->kobj
, &pm_qos_flags_attr_group
);
704 void rpm_sysfs_remove(struct device
*dev
)
706 sysfs_unmerge_group(&dev
->kobj
, &pm_runtime_attr_group
);
709 void dpm_sysfs_remove(struct device
*dev
)
711 dev_pm_qos_constraints_destroy(dev
);
712 rpm_sysfs_remove(dev
);
713 sysfs_unmerge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
714 sysfs_remove_group(&dev
->kobj
, &pm_attr_group
);