blob: 17b7934f31cb00c014688d6d0e197886687c3730 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * drivers/base/power/sysfs.c - sysfs entries for device PM
3 */
4
5#include <linux/device.h>
Tim Schmielau8c65b4a2005-11-07 00:59:43 -08006#include <linux/string.h>
Rafael J. Wysocki53823632010-01-23 22:02:51 +01007#include <linux/pm_runtime.h>
Arun Sharma600634972011-07-26 16:09:06 -07008#include <linux/atomic.h>
Arjan van de Ven8d4b9d12010-07-19 02:01:06 +02009#include <linux/jiffies.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include "power.h"
11
David Brownell0ac85242005-09-12 19:39:34 -070012/*
Rafael J. Wysocki53823632010-01-23 22:02:51 +010013 * 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 *
David Brownell0ac85242005-09-12 19:39:34 -070028 * 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.
Rafael J. Wysocki5a2eb852010-01-23 22:25:23 +010059 *
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.
Rafael J. Wysockic125e962010-07-05 22:43:53 +020077 *
Alan Stern15bcb91d2010-09-25 23:35:21 +020078 * 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 *
Rafael J. Wysockic125e962010-07-05 22:43:53 +020090 * wakeup_count - Report the number of wakeup events related to the device
David Brownell0ac85242005-09-12 19:39:34 -070091 */
92
93static const char enabled[] = "enabled";
94static const char disabled[] = "disabled";
95
Alan Stern7490e442010-09-25 23:35:15 +020096const char power_group_name[] = "power";
97EXPORT_SYMBOL_GPL(power_group_name);
98
Rafael J. Wysocki53823632010-01-23 22:02:51 +010099#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;
Alan Stern69c843b2011-07-06 10:52:23 +0200119 device_lock(dev);
Rafael J. Wysocki53823632010-01-23 22:02:51 +0100120 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
Alan Stern69c843b2011-07-06 10:52:23 +0200125 n = -EINVAL;
126 device_unlock(dev);
Rafael J. Wysocki53823632010-01-23 22:02:51 +0100127 return n;
128}
129
130static DEVICE_ATTR(control, 0644, control_show, control_store);
Alan Stern0fcb4ee2010-07-08 00:05:37 +0200131
Arjan van de Ven8d4b9d12010-07-19 02:01:06 +0200132static 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
Alan Stern0fcb4ee2010-07-08 00:05:37 +0200159static 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);
Alan Stern15bcb91d2010-09-25 23:35:21 +0200190
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
Alan Stern69c843b2011-07-06 10:52:23 +0200210 device_lock(dev);
Alan Stern15bcb91d2010-09-25 23:35:21 +0200211 pm_runtime_set_autosuspend_delay(dev, delay);
Alan Stern69c843b2011-07-06 10:52:23 +0200212 device_unlock(dev);
Alan Stern15bcb91d2010-09-25 23:35:21 +0200213 return n;
214}
215
216static DEVICE_ATTR(autosuspend_delay_ms, 0644, autosuspend_delay_ms_show,
217 autosuspend_delay_ms_store);
218
Rafael J. Wysockie7623182011-05-07 18:11:52 +0200219#endif /* CONFIG_PM_RUNTIME */
Rafael J. Wysocki53823632010-01-23 22:02:51 +0100220
Rafael J. Wysockie7623182011-05-07 18:11:52 +0200221#ifdef CONFIG_PM_SLEEP
David Brownell0ac85242005-09-12 19:39:34 -0700222static 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
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200256static ssize_t wakeup_count_show(struct device *dev,
257 struct device_attribute *attr, char *buf)
258{
Rafael J. Wysocki074037e2010-09-22 22:09:10 +0200259 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");
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200269}
270
271static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL);
Rafael J. Wysocki074037e2010-09-22 22:09:10 +0200272
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 */
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200375
Dominik Brodowskic92445f2010-04-23 20:32:23 +0200376#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
Dominik Brodowskic92445f2010-04-23 20:32:23 +0200404static DEVICE_ATTR(runtime_usage, 0444, rtpm_usagecount_show, NULL);
405static DEVICE_ATTR(runtime_active_kids, 0444, rtpm_children_show, NULL);
Dominik Brodowskic92445f2010-04-23 20:32:23 +0200406static DEVICE_ATTR(runtime_enabled, 0444, rtpm_enabled_show, NULL);
407
408#endif
409
Rafael J. Wysocki5a2eb852010-01-23 22:25:23 +0100410static 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);
Dominik Brodowskic92445f2010-04-23 20:32:23 +0200436#endif /* CONFIG_PM_ADVANCED_DEBUG */
David Brownell0ac85242005-09-12 19:39:34 -0700437
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100438static struct attribute *power_attrs[] = {
439#ifdef CONFIG_PM_ADVANCED_DEBUG
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200440#ifdef CONFIG_PM_SLEEP
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100441 &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,
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200460 &dev_attr_wakeup_count.attr,
Rafael J. Wysocki074037e2010-09-22 22:09:10 +0200461 &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,
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200467#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 NULL,
469};
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100470static struct attribute_group pm_wakeup_attr_group = {
Alan Stern7490e442010-09-25 23:35:15 +0200471 .name = power_group_name,
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100472 .attrs = wakeup_attrs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473};
474
Alan Stern7490e442010-09-25 23:35:15 +0200475static struct attribute *runtime_attrs[] = {
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100476#ifdef CONFIG_PM_RUNTIME
Alan Stern7490e442010-09-25 23:35:15 +0200477#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,
Alan Stern15bcb91d2010-09-25 23:35:21 +0200483 &dev_attr_autosuspend_delay_ms.attr,
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100484#endif /* CONFIG_PM_RUNTIME */
Alan Stern7490e442010-09-25 23:35:15 +0200485 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);
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100497 if (rc)
498 return rc;
499
500 if (pm_runtime_callbacks_present(dev)) {
Alan Stern7490e442010-09-25 23:35:15 +0200501 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
502 if (rc)
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100503 goto err_out;
Alan Stern7490e442010-09-25 23:35:15 +0200504 }
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100505
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);
Alan Stern7490e442010-09-25 23:35:15 +0200519 return rc;
520}
521
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100522int 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
Alan Stern7490e442010-09-25 23:35:15 +0200532void 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);
Rafael J. Wysockicb8f51b2011-02-08 23:26:02 +0100540 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
Alan Stern7490e442010-09-25 23:35:15 +0200541 sysfs_remove_group(&dev->kobj, &pm_attr_group);
542}