Merge branches 'x86-cleanups-for-linus' and 'x86-cpufeature-for-linus' of git://git...
[deliverable/linux.git] / drivers / base / power / sysfs.c
1 /*
2 * drivers/base/power/sysfs.c - sysfs entries for device PM
3 */
4
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>
12 #include "power.h"
13
14 /*
15 * control - Report/change current runtime PM setting of the device
16 *
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:
20 *
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;
23 *
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
28 * it to be woken up.
29 *
30 * wakeup - Report/change current wakeup option for device
31 *
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:
35 *
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.
39 *
40 * (For example, unconfigured USB devices can't issue wakeups.)
41 *
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
48 * of band signaling.
49 *
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.
53 *
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.
61 *
62 * async - Report/change current async suspend setting for the device
63 *
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.
68 *
69 * All devices have one of the following two values for power/async:
70 *
71 * + "enabled\n" to permit the asynchronous suspend/resume of the device;
72 * + "disabled\n" to forbid it;
73 *
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.
79 *
80 * autosuspend_delay_ms - Report/change a device's autosuspend_delay value
81 *
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
87 * suspended.
88 *
89 * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
90 * value are used only if the driver calls pm_runtime_use_autosuspend().
91 *
92 * wakeup_count - Report the number of wakeup events related to the device
93 */
94
95 static const char enabled[] = "enabled";
96 static const char disabled[] = "disabled";
97
98 const char power_group_name[] = "power";
99 EXPORT_SYMBOL_GPL(power_group_name);
100
101 #ifdef CONFIG_PM_RUNTIME
102 static const char ctrl_auto[] = "auto";
103 static const char ctrl_on[] = "on";
104
105 static ssize_t control_show(struct device *dev, struct device_attribute *attr,
106 char *buf)
107 {
108 return sprintf(buf, "%s\n",
109 dev->power.runtime_auto ? ctrl_auto : ctrl_on);
110 }
111
112 static ssize_t control_store(struct device * dev, struct device_attribute *attr,
113 const char * buf, size_t n)
114 {
115 char *cp;
116 int len = n;
117
118 cp = memchr(buf, '\n', n);
119 if (cp)
120 len = cp - buf;
121 device_lock(dev);
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);
126 else
127 n = -EINVAL;
128 device_unlock(dev);
129 return n;
130 }
131
132 static DEVICE_ATTR(control, 0644, control_show, control_store);
133
134 static ssize_t rtpm_active_time_show(struct device *dev,
135 struct device_attribute *attr, char *buf)
136 {
137 int ret;
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);
142 return ret;
143 }
144
145 static DEVICE_ATTR(runtime_active_time, 0444, rtpm_active_time_show, NULL);
146
147 static ssize_t rtpm_suspended_time_show(struct device *dev,
148 struct device_attribute *attr, char *buf)
149 {
150 int ret;
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);
156 return ret;
157 }
158
159 static DEVICE_ATTR(runtime_suspended_time, 0444, rtpm_suspended_time_show, NULL);
160
161 static ssize_t rtpm_status_show(struct device *dev,
162 struct device_attribute *attr, char *buf)
163 {
164 const char *p;
165
166 if (dev->power.runtime_error) {
167 p = "error\n";
168 } else if (dev->power.disable_depth) {
169 p = "unsupported\n";
170 } else {
171 switch (dev->power.runtime_status) {
172 case RPM_SUSPENDED:
173 p = "suspended\n";
174 break;
175 case RPM_SUSPENDING:
176 p = "suspending\n";
177 break;
178 case RPM_RESUMING:
179 p = "resuming\n";
180 break;
181 case RPM_ACTIVE:
182 p = "active\n";
183 break;
184 default:
185 return -EIO;
186 }
187 }
188 return sprintf(buf, p);
189 }
190
191 static DEVICE_ATTR(runtime_status, 0444, rtpm_status_show, NULL);
192
193 static ssize_t autosuspend_delay_ms_show(struct device *dev,
194 struct device_attribute *attr, char *buf)
195 {
196 if (!dev->power.use_autosuspend)
197 return -EIO;
198 return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
199 }
200
201 static ssize_t autosuspend_delay_ms_store(struct device *dev,
202 struct device_attribute *attr, const char *buf, size_t n)
203 {
204 long delay;
205
206 if (!dev->power.use_autosuspend)
207 return -EIO;
208
209 if (strict_strtol(buf, 10, &delay) != 0 || delay != (int) delay)
210 return -EINVAL;
211
212 device_lock(dev);
213 pm_runtime_set_autosuspend_delay(dev, delay);
214 device_unlock(dev);
215 return n;
216 }
217
218 static DEVICE_ATTR(autosuspend_delay_ms, 0644, autosuspend_delay_ms_show,
219 autosuspend_delay_ms_store);
220
221 static ssize_t pm_qos_latency_show(struct device *dev,
222 struct device_attribute *attr, char *buf)
223 {
224 return sprintf(buf, "%d\n", dev->power.pq_req->node.prio);
225 }
226
227 static ssize_t pm_qos_latency_store(struct device *dev,
228 struct device_attribute *attr,
229 const char *buf, size_t n)
230 {
231 s32 value;
232 int ret;
233
234 if (kstrtos32(buf, 0, &value))
235 return -EINVAL;
236
237 if (value < 0)
238 return -EINVAL;
239
240 ret = dev_pm_qos_update_request(dev->power.pq_req, value);
241 return ret < 0 ? ret : n;
242 }
243
244 static DEVICE_ATTR(pm_qos_resume_latency_us, 0644,
245 pm_qos_latency_show, pm_qos_latency_store);
246 #endif /* CONFIG_PM_RUNTIME */
247
248 #ifdef CONFIG_PM_SLEEP
249 static ssize_t
250 wake_show(struct device * dev, struct device_attribute *attr, char * buf)
251 {
252 return sprintf(buf, "%s\n", device_can_wakeup(dev)
253 ? (device_may_wakeup(dev) ? enabled : disabled)
254 : "");
255 }
256
257 static ssize_t
258 wake_store(struct device * dev, struct device_attribute *attr,
259 const char * buf, size_t n)
260 {
261 char *cp;
262 int len = n;
263
264 if (!device_can_wakeup(dev))
265 return -EINVAL;
266
267 cp = memchr(buf, '\n', n);
268 if (cp)
269 len = cp - buf;
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);
276 else
277 return -EINVAL;
278 return n;
279 }
280
281 static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
282
283 static ssize_t wakeup_count_show(struct device *dev,
284 struct device_attribute *attr, char *buf)
285 {
286 unsigned long count = 0;
287 bool enabled = false;
288
289 spin_lock_irq(&dev->power.lock);
290 if (dev->power.wakeup) {
291 count = dev->power.wakeup->event_count;
292 enabled = true;
293 }
294 spin_unlock_irq(&dev->power.lock);
295 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
296 }
297
298 static DEVICE_ATTR(wakeup_count, 0444, wakeup_count_show, NULL);
299
300 static ssize_t wakeup_active_count_show(struct device *dev,
301 struct device_attribute *attr, char *buf)
302 {
303 unsigned long count = 0;
304 bool enabled = false;
305
306 spin_lock_irq(&dev->power.lock);
307 if (dev->power.wakeup) {
308 count = dev->power.wakeup->active_count;
309 enabled = true;
310 }
311 spin_unlock_irq(&dev->power.lock);
312 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
313 }
314
315 static DEVICE_ATTR(wakeup_active_count, 0444, wakeup_active_count_show, NULL);
316
317 static ssize_t wakeup_abort_count_show(struct device *dev,
318 struct device_attribute *attr,
319 char *buf)
320 {
321 unsigned long count = 0;
322 bool enabled = false;
323
324 spin_lock_irq(&dev->power.lock);
325 if (dev->power.wakeup) {
326 count = dev->power.wakeup->wakeup_count;
327 enabled = true;
328 }
329 spin_unlock_irq(&dev->power.lock);
330 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
331 }
332
333 static DEVICE_ATTR(wakeup_abort_count, 0444, wakeup_abort_count_show, NULL);
334
335 static ssize_t wakeup_expire_count_show(struct device *dev,
336 struct device_attribute *attr,
337 char *buf)
338 {
339 unsigned long count = 0;
340 bool enabled = false;
341
342 spin_lock_irq(&dev->power.lock);
343 if (dev->power.wakeup) {
344 count = dev->power.wakeup->expire_count;
345 enabled = true;
346 }
347 spin_unlock_irq(&dev->power.lock);
348 return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
349 }
350
351 static DEVICE_ATTR(wakeup_expire_count, 0444, wakeup_expire_count_show, NULL);
352
353 static ssize_t wakeup_active_show(struct device *dev,
354 struct device_attribute *attr, char *buf)
355 {
356 unsigned int active = 0;
357 bool enabled = false;
358
359 spin_lock_irq(&dev->power.lock);
360 if (dev->power.wakeup) {
361 active = dev->power.wakeup->active;
362 enabled = true;
363 }
364 spin_unlock_irq(&dev->power.lock);
365 return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
366 }
367
368 static DEVICE_ATTR(wakeup_active, 0444, wakeup_active_show, NULL);
369
370 static ssize_t wakeup_total_time_show(struct device *dev,
371 struct device_attribute *attr, char *buf)
372 {
373 s64 msec = 0;
374 bool enabled = false;
375
376 spin_lock_irq(&dev->power.lock);
377 if (dev->power.wakeup) {
378 msec = ktime_to_ms(dev->power.wakeup->total_time);
379 enabled = true;
380 }
381 spin_unlock_irq(&dev->power.lock);
382 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
383 }
384
385 static DEVICE_ATTR(wakeup_total_time_ms, 0444, wakeup_total_time_show, NULL);
386
387 static ssize_t wakeup_max_time_show(struct device *dev,
388 struct device_attribute *attr, char *buf)
389 {
390 s64 msec = 0;
391 bool enabled = false;
392
393 spin_lock_irq(&dev->power.lock);
394 if (dev->power.wakeup) {
395 msec = ktime_to_ms(dev->power.wakeup->max_time);
396 enabled = true;
397 }
398 spin_unlock_irq(&dev->power.lock);
399 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
400 }
401
402 static DEVICE_ATTR(wakeup_max_time_ms, 0444, wakeup_max_time_show, NULL);
403
404 static ssize_t wakeup_last_time_show(struct device *dev,
405 struct device_attribute *attr, char *buf)
406 {
407 s64 msec = 0;
408 bool enabled = false;
409
410 spin_lock_irq(&dev->power.lock);
411 if (dev->power.wakeup) {
412 msec = ktime_to_ms(dev->power.wakeup->last_time);
413 enabled = true;
414 }
415 spin_unlock_irq(&dev->power.lock);
416 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
417 }
418
419 static DEVICE_ATTR(wakeup_last_time_ms, 0444, wakeup_last_time_show, NULL);
420
421 #ifdef CONFIG_PM_AUTOSLEEP
422 static ssize_t wakeup_prevent_sleep_time_show(struct device *dev,
423 struct device_attribute *attr,
424 char *buf)
425 {
426 s64 msec = 0;
427 bool enabled = false;
428
429 spin_lock_irq(&dev->power.lock);
430 if (dev->power.wakeup) {
431 msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
432 enabled = true;
433 }
434 spin_unlock_irq(&dev->power.lock);
435 return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
436 }
437
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 */
442
443 #ifdef CONFIG_PM_ADVANCED_DEBUG
444 #ifdef CONFIG_PM_RUNTIME
445
446 static ssize_t rtpm_usagecount_show(struct device *dev,
447 struct device_attribute *attr, char *buf)
448 {
449 return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
450 }
451
452 static ssize_t rtpm_children_show(struct device *dev,
453 struct device_attribute *attr, char *buf)
454 {
455 return sprintf(buf, "%d\n", dev->power.ignore_children ?
456 0 : atomic_read(&dev->power.child_count));
457 }
458
459 static ssize_t rtpm_enabled_show(struct device *dev,
460 struct device_attribute *attr, char *buf)
461 {
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");
469 }
470
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);
474
475 #endif
476
477 #ifdef CONFIG_PM_SLEEP
478
479 static ssize_t async_show(struct device *dev, struct device_attribute *attr,
480 char *buf)
481 {
482 return sprintf(buf, "%s\n",
483 device_async_suspend_enabled(dev) ? enabled : disabled);
484 }
485
486 static ssize_t async_store(struct device *dev, struct device_attribute *attr,
487 const char *buf, size_t n)
488 {
489 char *cp;
490 int len = n;
491
492 cp = memchr(buf, '\n', n);
493 if (cp)
494 len = cp - buf;
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);
499 else
500 return -EINVAL;
501 return n;
502 }
503
504 static DEVICE_ATTR(async, 0644, async_show, async_store);
505
506 #endif
507 #endif /* CONFIG_PM_ADVANCED_DEBUG */
508
509 static struct attribute *power_attrs[] = {
510 #ifdef CONFIG_PM_ADVANCED_DEBUG
511 #ifdef CONFIG_PM_SLEEP
512 &dev_attr_async.attr,
513 #endif
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,
519 #endif
520 #endif /* CONFIG_PM_ADVANCED_DEBUG */
521 NULL,
522 };
523 static struct attribute_group pm_attr_group = {
524 .name = power_group_name,
525 .attrs = power_attrs,
526 };
527
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,
541 #endif
542 #endif
543 NULL,
544 };
545 static struct attribute_group pm_wakeup_attr_group = {
546 .name = power_group_name,
547 .attrs = wakeup_attrs,
548 };
549
550 static struct attribute *runtime_attrs[] = {
551 #ifdef CONFIG_PM_RUNTIME
552 #ifndef CONFIG_PM_ADVANCED_DEBUG
553 &dev_attr_runtime_status.attr,
554 #endif
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 */
560 NULL,
561 };
562 static struct attribute_group pm_runtime_attr_group = {
563 .name = power_group_name,
564 .attrs = runtime_attrs,
565 };
566
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 */
571 NULL,
572 };
573 static struct attribute_group pm_qos_attr_group = {
574 .name = power_group_name,
575 .attrs = pm_qos_attrs,
576 };
577
578 int dpm_sysfs_add(struct device *dev)
579 {
580 int rc;
581
582 rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
583 if (rc)
584 return rc;
585
586 if (pm_runtime_callbacks_present(dev)) {
587 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
588 if (rc)
589 goto err_out;
590 }
591
592 if (device_can_wakeup(dev)) {
593 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
594 if (rc) {
595 if (pm_runtime_callbacks_present(dev))
596 sysfs_unmerge_group(&dev->kobj,
597 &pm_runtime_attr_group);
598 goto err_out;
599 }
600 }
601 return 0;
602
603 err_out:
604 sysfs_remove_group(&dev->kobj, &pm_attr_group);
605 return rc;
606 }
607
608 int wakeup_sysfs_add(struct device *dev)
609 {
610 return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
611 }
612
613 void wakeup_sysfs_remove(struct device *dev)
614 {
615 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
616 }
617
618 int pm_qos_sysfs_add(struct device *dev)
619 {
620 return sysfs_merge_group(&dev->kobj, &pm_qos_attr_group);
621 }
622
623 void pm_qos_sysfs_remove(struct device *dev)
624 {
625 sysfs_unmerge_group(&dev->kobj, &pm_qos_attr_group);
626 }
627
628 void rpm_sysfs_remove(struct device *dev)
629 {
630 sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
631 }
632
633 void dpm_sysfs_remove(struct device *dev)
634 {
635 rpm_sysfs_remove(dev);
636 sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
637 sysfs_remove_group(&dev->kobj, &pm_attr_group);
638 }
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