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 (strict_strtol(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
->power
.pq_req
->node
.prio
);
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
.pq_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
);
246 #endif /* CONFIG_PM_RUNTIME */
248 #ifdef CONFIG_PM_SLEEP
250 wake_show(struct device
* dev
, struct device_attribute
*attr
, char * buf
)
252 return sprintf(buf
, "%s\n", device_can_wakeup(dev
)
253 ? (device_may_wakeup(dev
) ? enabled
: disabled
)
258 wake_store(struct device
* dev
, struct device_attribute
*attr
,
259 const char * buf
, size_t n
)
264 if (!device_can_wakeup(dev
))
267 cp
= memchr(buf
, '\n', n
);
270 if (len
== sizeof enabled
- 1
271 && strncmp(buf
, enabled
, sizeof enabled
- 1) == 0)
272 device_set_wakeup_enable(dev
, 1);
273 else if (len
== sizeof disabled
- 1
274 && strncmp(buf
, disabled
, sizeof disabled
- 1) == 0)
275 device_set_wakeup_enable(dev
, 0);
281 static DEVICE_ATTR(wakeup
, 0644, wake_show
, wake_store
);
283 static ssize_t
wakeup_count_show(struct device
*dev
,
284 struct device_attribute
*attr
, char *buf
)
286 unsigned long count
= 0;
287 bool enabled
= false;
289 spin_lock_irq(&dev
->power
.lock
);
290 if (dev
->power
.wakeup
) {
291 count
= dev
->power
.wakeup
->event_count
;
294 spin_unlock_irq(&dev
->power
.lock
);
295 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
298 static DEVICE_ATTR(wakeup_count
, 0444, wakeup_count_show
, NULL
);
300 static ssize_t
wakeup_active_count_show(struct device
*dev
,
301 struct device_attribute
*attr
, char *buf
)
303 unsigned long count
= 0;
304 bool enabled
= false;
306 spin_lock_irq(&dev
->power
.lock
);
307 if (dev
->power
.wakeup
) {
308 count
= dev
->power
.wakeup
->active_count
;
311 spin_unlock_irq(&dev
->power
.lock
);
312 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
315 static DEVICE_ATTR(wakeup_active_count
, 0444, wakeup_active_count_show
, NULL
);
317 static ssize_t
wakeup_abort_count_show(struct device
*dev
,
318 struct device_attribute
*attr
,
321 unsigned long count
= 0;
322 bool enabled
= false;
324 spin_lock_irq(&dev
->power
.lock
);
325 if (dev
->power
.wakeup
) {
326 count
= dev
->power
.wakeup
->wakeup_count
;
329 spin_unlock_irq(&dev
->power
.lock
);
330 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
333 static DEVICE_ATTR(wakeup_abort_count
, 0444, wakeup_abort_count_show
, NULL
);
335 static ssize_t
wakeup_expire_count_show(struct device
*dev
,
336 struct device_attribute
*attr
,
339 unsigned long count
= 0;
340 bool enabled
= false;
342 spin_lock_irq(&dev
->power
.lock
);
343 if (dev
->power
.wakeup
) {
344 count
= dev
->power
.wakeup
->expire_count
;
347 spin_unlock_irq(&dev
->power
.lock
);
348 return enabled
? sprintf(buf
, "%lu\n", count
) : sprintf(buf
, "\n");
351 static DEVICE_ATTR(wakeup_expire_count
, 0444, wakeup_expire_count_show
, NULL
);
353 static ssize_t
wakeup_active_show(struct device
*dev
,
354 struct device_attribute
*attr
, char *buf
)
356 unsigned int active
= 0;
357 bool enabled
= false;
359 spin_lock_irq(&dev
->power
.lock
);
360 if (dev
->power
.wakeup
) {
361 active
= dev
->power
.wakeup
->active
;
364 spin_unlock_irq(&dev
->power
.lock
);
365 return enabled
? sprintf(buf
, "%u\n", active
) : sprintf(buf
, "\n");
368 static DEVICE_ATTR(wakeup_active
, 0444, wakeup_active_show
, NULL
);
370 static ssize_t
wakeup_total_time_show(struct device
*dev
,
371 struct device_attribute
*attr
, char *buf
)
374 bool enabled
= false;
376 spin_lock_irq(&dev
->power
.lock
);
377 if (dev
->power
.wakeup
) {
378 msec
= ktime_to_ms(dev
->power
.wakeup
->total_time
);
381 spin_unlock_irq(&dev
->power
.lock
);
382 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
385 static DEVICE_ATTR(wakeup_total_time_ms
, 0444, wakeup_total_time_show
, NULL
);
387 static ssize_t
wakeup_max_time_show(struct device
*dev
,
388 struct device_attribute
*attr
, char *buf
)
391 bool enabled
= false;
393 spin_lock_irq(&dev
->power
.lock
);
394 if (dev
->power
.wakeup
) {
395 msec
= ktime_to_ms(dev
->power
.wakeup
->max_time
);
398 spin_unlock_irq(&dev
->power
.lock
);
399 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
402 static DEVICE_ATTR(wakeup_max_time_ms
, 0444, wakeup_max_time_show
, NULL
);
404 static ssize_t
wakeup_last_time_show(struct device
*dev
,
405 struct device_attribute
*attr
, char *buf
)
408 bool enabled
= false;
410 spin_lock_irq(&dev
->power
.lock
);
411 if (dev
->power
.wakeup
) {
412 msec
= ktime_to_ms(dev
->power
.wakeup
->last_time
);
415 spin_unlock_irq(&dev
->power
.lock
);
416 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
419 static DEVICE_ATTR(wakeup_last_time_ms
, 0444, wakeup_last_time_show
, NULL
);
421 #ifdef CONFIG_PM_AUTOSLEEP
422 static ssize_t
wakeup_prevent_sleep_time_show(struct device
*dev
,
423 struct device_attribute
*attr
,
427 bool enabled
= false;
429 spin_lock_irq(&dev
->power
.lock
);
430 if (dev
->power
.wakeup
) {
431 msec
= ktime_to_ms(dev
->power
.wakeup
->prevent_sleep_time
);
434 spin_unlock_irq(&dev
->power
.lock
);
435 return enabled
? sprintf(buf
, "%lld\n", msec
) : sprintf(buf
, "\n");
438 static DEVICE_ATTR(wakeup_prevent_sleep_time_ms
, 0444,
439 wakeup_prevent_sleep_time_show
, NULL
);
440 #endif /* CONFIG_PM_AUTOSLEEP */
441 #endif /* CONFIG_PM_SLEEP */
443 #ifdef CONFIG_PM_ADVANCED_DEBUG
444 #ifdef CONFIG_PM_RUNTIME
446 static ssize_t
rtpm_usagecount_show(struct device
*dev
,
447 struct device_attribute
*attr
, char *buf
)
449 return sprintf(buf
, "%d\n", atomic_read(&dev
->power
.usage_count
));
452 static ssize_t
rtpm_children_show(struct device
*dev
,
453 struct device_attribute
*attr
, char *buf
)
455 return sprintf(buf
, "%d\n", dev
->power
.ignore_children
?
456 0 : atomic_read(&dev
->power
.child_count
));
459 static ssize_t
rtpm_enabled_show(struct device
*dev
,
460 struct device_attribute
*attr
, char *buf
)
462 if ((dev
->power
.disable_depth
) && (dev
->power
.runtime_auto
== false))
463 return sprintf(buf
, "disabled & forbidden\n");
464 else if (dev
->power
.disable_depth
)
465 return sprintf(buf
, "disabled\n");
466 else if (dev
->power
.runtime_auto
== false)
467 return sprintf(buf
, "forbidden\n");
468 return sprintf(buf
, "enabled\n");
471 static DEVICE_ATTR(runtime_usage
, 0444, rtpm_usagecount_show
, NULL
);
472 static DEVICE_ATTR(runtime_active_kids
, 0444, rtpm_children_show
, NULL
);
473 static DEVICE_ATTR(runtime_enabled
, 0444, rtpm_enabled_show
, NULL
);
477 #ifdef CONFIG_PM_SLEEP
479 static ssize_t
async_show(struct device
*dev
, struct device_attribute
*attr
,
482 return sprintf(buf
, "%s\n",
483 device_async_suspend_enabled(dev
) ? enabled
: disabled
);
486 static ssize_t
async_store(struct device
*dev
, struct device_attribute
*attr
,
487 const char *buf
, size_t n
)
492 cp
= memchr(buf
, '\n', n
);
495 if (len
== sizeof enabled
- 1 && strncmp(buf
, enabled
, len
) == 0)
496 device_enable_async_suspend(dev
);
497 else if (len
== sizeof disabled
- 1 && strncmp(buf
, disabled
, len
) == 0)
498 device_disable_async_suspend(dev
);
504 static DEVICE_ATTR(async
, 0644, async_show
, async_store
);
507 #endif /* CONFIG_PM_ADVANCED_DEBUG */
509 static struct attribute
*power_attrs
[] = {
510 #ifdef CONFIG_PM_ADVANCED_DEBUG
511 #ifdef CONFIG_PM_SLEEP
512 &dev_attr_async
.attr
,
514 #ifdef CONFIG_PM_RUNTIME
515 &dev_attr_runtime_status
.attr
,
516 &dev_attr_runtime_usage
.attr
,
517 &dev_attr_runtime_active_kids
.attr
,
518 &dev_attr_runtime_enabled
.attr
,
520 #endif /* CONFIG_PM_ADVANCED_DEBUG */
523 static struct attribute_group pm_attr_group
= {
524 .name
= power_group_name
,
525 .attrs
= power_attrs
,
528 static struct attribute
*wakeup_attrs
[] = {
529 #ifdef CONFIG_PM_SLEEP
530 &dev_attr_wakeup
.attr
,
531 &dev_attr_wakeup_count
.attr
,
532 &dev_attr_wakeup_active_count
.attr
,
533 &dev_attr_wakeup_abort_count
.attr
,
534 &dev_attr_wakeup_expire_count
.attr
,
535 &dev_attr_wakeup_active
.attr
,
536 &dev_attr_wakeup_total_time_ms
.attr
,
537 &dev_attr_wakeup_max_time_ms
.attr
,
538 &dev_attr_wakeup_last_time_ms
.attr
,
539 #ifdef CONFIG_PM_AUTOSLEEP
540 &dev_attr_wakeup_prevent_sleep_time_ms
.attr
,
545 static struct attribute_group pm_wakeup_attr_group
= {
546 .name
= power_group_name
,
547 .attrs
= wakeup_attrs
,
550 static struct attribute
*runtime_attrs
[] = {
551 #ifdef CONFIG_PM_RUNTIME
552 #ifndef CONFIG_PM_ADVANCED_DEBUG
553 &dev_attr_runtime_status
.attr
,
555 &dev_attr_control
.attr
,
556 &dev_attr_runtime_suspended_time
.attr
,
557 &dev_attr_runtime_active_time
.attr
,
558 &dev_attr_autosuspend_delay_ms
.attr
,
559 #endif /* CONFIG_PM_RUNTIME */
562 static struct attribute_group pm_runtime_attr_group
= {
563 .name
= power_group_name
,
564 .attrs
= runtime_attrs
,
567 static struct attribute
*pm_qos_attrs
[] = {
568 #ifdef CONFIG_PM_RUNTIME
569 &dev_attr_pm_qos_resume_latency_us
.attr
,
570 #endif /* CONFIG_PM_RUNTIME */
573 static struct attribute_group pm_qos_attr_group
= {
574 .name
= power_group_name
,
575 .attrs
= pm_qos_attrs
,
578 int dpm_sysfs_add(struct device
*dev
)
582 rc
= sysfs_create_group(&dev
->kobj
, &pm_attr_group
);
586 if (pm_runtime_callbacks_present(dev
)) {
587 rc
= sysfs_merge_group(&dev
->kobj
, &pm_runtime_attr_group
);
592 if (device_can_wakeup(dev
)) {
593 rc
= sysfs_merge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
595 if (pm_runtime_callbacks_present(dev
))
596 sysfs_unmerge_group(&dev
->kobj
,
597 &pm_runtime_attr_group
);
604 sysfs_remove_group(&dev
->kobj
, &pm_attr_group
);
608 int wakeup_sysfs_add(struct device
*dev
)
610 return sysfs_merge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
613 void wakeup_sysfs_remove(struct device
*dev
)
615 sysfs_unmerge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
618 int pm_qos_sysfs_add(struct device
*dev
)
620 return sysfs_merge_group(&dev
->kobj
, &pm_qos_attr_group
);
623 void pm_qos_sysfs_remove(struct device
*dev
)
625 sysfs_unmerge_group(&dev
->kobj
, &pm_qos_attr_group
);
628 void rpm_sysfs_remove(struct device
*dev
)
630 sysfs_unmerge_group(&dev
->kobj
, &pm_runtime_attr_group
);
633 void dpm_sysfs_remove(struct device
*dev
)
635 rpm_sysfs_remove(dev
);
636 sysfs_unmerge_group(&dev
->kobj
, &pm_wakeup_attr_group
);
637 sysfs_remove_group(&dev
->kobj
, &pm_attr_group
);