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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * kernel/power/main.c - PM subsystem core functionality.
4 *
5 * Copyright (c) 2003 Patrick Mochel
6 * Copyright (c) 2003 Open Source Development Lab
7 */
8
9#include <linux/export.h>
10#include <linux/kobject.h>
11#include <linux/string.h>
12#include <linux/pm-trace.h>
13#include <linux/workqueue.h>
14#include <linux/debugfs.h>
15#include <linux/seq_file.h>
16#include <linux/suspend.h>
17#include <linux/syscalls.h>
18#include <linux/pm_runtime.h>
19
20#include "power.h"
21
22#ifdef CONFIG_PM_SLEEP
23
24void lock_system_sleep(void)
25{
26 current->flags |= PF_FREEZER_SKIP;
27 mutex_lock(&system_transition_mutex);
28}
29EXPORT_SYMBOL_GPL(lock_system_sleep);
30
31void unlock_system_sleep(void)
32{
33 /*
34 * Don't use freezer_count() because we don't want the call to
35 * try_to_freeze() here.
36 *
37 * Reason:
38 * Fundamentally, we just don't need it, because freezing condition
39 * doesn't come into effect until we release the
40 * system_transition_mutex lock, since the freezer always works with
41 * system_transition_mutex held.
42 *
43 * More importantly, in the case of hibernation,
44 * unlock_system_sleep() gets called in snapshot_read() and
45 * snapshot_write() when the freezing condition is still in effect.
46 * Which means, if we use try_to_freeze() here, it would make them
47 * enter the refrigerator, thus causing hibernation to lockup.
48 */
49 current->flags &= ~PF_FREEZER_SKIP;
50 mutex_unlock(&system_transition_mutex);
51}
52EXPORT_SYMBOL_GPL(unlock_system_sleep);
53
54void ksys_sync_helper(void)
55{
56 ktime_t start;
57 long elapsed_msecs;
58
59 start = ktime_get();
60 ksys_sync();
61 elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
62 pr_info("Filesystems sync: %ld.%03ld seconds\n",
63 elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
64}
65EXPORT_SYMBOL_GPL(ksys_sync_helper);
66
67/* Routines for PM-transition notifications */
68
69static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
70
71int register_pm_notifier(struct notifier_block *nb)
72{
73 return blocking_notifier_chain_register(&pm_chain_head, nb);
74}
75EXPORT_SYMBOL_GPL(register_pm_notifier);
76
77int unregister_pm_notifier(struct notifier_block *nb)
78{
79 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
80}
81EXPORT_SYMBOL_GPL(unregister_pm_notifier);
82
83int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
84{
85 int ret;
86
87 ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
88 nr_to_call, nr_calls);
89
90 return notifier_to_errno(ret);
91}
92int pm_notifier_call_chain(unsigned long val)
93{
94 return __pm_notifier_call_chain(val, -1, NULL);
95}
96
97/* If set, devices may be suspended and resumed asynchronously. */
98int pm_async_enabled = 1;
99
100static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
101 char *buf)
102{
103 return sprintf(buf, "%d\n", pm_async_enabled);
104}
105
106static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
107 const char *buf, size_t n)
108{
109 unsigned long val;
110
111 if (kstrtoul(buf, 10, &val))
112 return -EINVAL;
113
114 if (val > 1)
115 return -EINVAL;
116
117 pm_async_enabled = val;
118 return n;
119}
120
121power_attr(pm_async);
122
123#ifdef CONFIG_SUSPEND
124static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
125 char *buf)
126{
127 char *s = buf;
128 suspend_state_t i;
129
130 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
131 if (mem_sleep_states[i]) {
132 const char *label = mem_sleep_states[i];
133
134 if (mem_sleep_current == i)
135 s += sprintf(s, "[%s] ", label);
136 else
137 s += sprintf(s, "%s ", label);
138 }
139
140 /* Convert the last space to a newline if needed. */
141 if (s != buf)
142 *(s-1) = '\n';
143
144 return (s - buf);
145}
146
147static suspend_state_t decode_suspend_state(const char *buf, size_t n)
148{
149 suspend_state_t state;
150 char *p;
151 int len;
152
153 p = memchr(buf, '\n', n);
154 len = p ? p - buf : n;
155
156 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
157 const char *label = mem_sleep_states[state];
158
159 if (label && len == strlen(label) && !strncmp(buf, label, len))
160 return state;
161 }
162
163 return PM_SUSPEND_ON;
164}
165
166static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
167 const char *buf, size_t n)
168{
169 suspend_state_t state;
170 int error;
171
172 error = pm_autosleep_lock();
173 if (error)
174 return error;
175
176 if (pm_autosleep_state() > PM_SUSPEND_ON) {
177 error = -EBUSY;
178 goto out;
179 }
180
181 state = decode_suspend_state(buf, n);
182 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
183 mem_sleep_current = state;
184 else
185 error = -EINVAL;
186
187 out:
188 pm_autosleep_unlock();
189 return error ? error : n;
190}
191
192power_attr(mem_sleep);
193
194/*
195 * sync_on_suspend: invoke ksys_sync_helper() before suspend.
196 *
197 * show() returns whether ksys_sync_helper() is invoked before suspend.
198 * store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it.
199 */
200bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC);
201
202static ssize_t sync_on_suspend_show(struct kobject *kobj,
203 struct kobj_attribute *attr, char *buf)
204{
205 return sprintf(buf, "%d\n", sync_on_suspend_enabled);
206}
207
208static ssize_t sync_on_suspend_store(struct kobject *kobj,
209 struct kobj_attribute *attr,
210 const char *buf, size_t n)
211{
212 unsigned long val;
213
214 if (kstrtoul(buf, 10, &val))
215 return -EINVAL;
216
217 if (val > 1)
218 return -EINVAL;
219
220 sync_on_suspend_enabled = !!val;
221 return n;
222}
223
224power_attr(sync_on_suspend);
225#endif /* CONFIG_SUSPEND */
226
227#ifdef CONFIG_PM_SLEEP_DEBUG
228int pm_test_level = TEST_NONE;
229
230static const char * const pm_tests[__TEST_AFTER_LAST] = {
231 [TEST_NONE] = "none",
232 [TEST_CORE] = "core",
233 [TEST_CPUS] = "processors",
234 [TEST_PLATFORM] = "platform",
235 [TEST_DEVICES] = "devices",
236 [TEST_FREEZER] = "freezer",
237};
238
239static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
240 char *buf)
241{
242 char *s = buf;
243 int level;
244
245 for (level = TEST_FIRST; level <= TEST_MAX; level++)
246 if (pm_tests[level]) {
247 if (level == pm_test_level)
248 s += sprintf(s, "[%s] ", pm_tests[level]);
249 else
250 s += sprintf(s, "%s ", pm_tests[level]);
251 }
252
253 if (s != buf)
254 /* convert the last space to a newline */
255 *(s-1) = '\n';
256
257 return (s - buf);
258}
259
260static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
261 const char *buf, size_t n)
262{
263 const char * const *s;
264 int level;
265 char *p;
266 int len;
267 int error = -EINVAL;
268
269 p = memchr(buf, '\n', n);
270 len = p ? p - buf : n;
271
272 lock_system_sleep();
273
274 level = TEST_FIRST;
275 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
276 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
277 pm_test_level = level;
278 error = 0;
279 break;
280 }
281
282 unlock_system_sleep();
283
284 return error ? error : n;
285}
286
287power_attr(pm_test);
288#endif /* CONFIG_PM_SLEEP_DEBUG */
289
290static char *suspend_step_name(enum suspend_stat_step step)
291{
292 switch (step) {
293 case SUSPEND_FREEZE:
294 return "freeze";
295 case SUSPEND_PREPARE:
296 return "prepare";
297 case SUSPEND_SUSPEND:
298 return "suspend";
299 case SUSPEND_SUSPEND_NOIRQ:
300 return "suspend_noirq";
301 case SUSPEND_RESUME_NOIRQ:
302 return "resume_noirq";
303 case SUSPEND_RESUME:
304 return "resume";
305 default:
306 return "";
307 }
308}
309
310#define suspend_attr(_name) \
311static ssize_t _name##_show(struct kobject *kobj, \
312 struct kobj_attribute *attr, char *buf) \
313{ \
314 return sprintf(buf, "%d\n", suspend_stats._name); \
315} \
316static struct kobj_attribute _name = __ATTR_RO(_name)
317
318suspend_attr(success);
319suspend_attr(fail);
320suspend_attr(failed_freeze);
321suspend_attr(failed_prepare);
322suspend_attr(failed_suspend);
323suspend_attr(failed_suspend_late);
324suspend_attr(failed_suspend_noirq);
325suspend_attr(failed_resume);
326suspend_attr(failed_resume_early);
327suspend_attr(failed_resume_noirq);
328
329static ssize_t last_failed_dev_show(struct kobject *kobj,
330 struct kobj_attribute *attr, char *buf)
331{
332 int index;
333 char *last_failed_dev = NULL;
334
335 index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
336 index %= REC_FAILED_NUM;
337 last_failed_dev = suspend_stats.failed_devs[index];
338
339 return sprintf(buf, "%s\n", last_failed_dev);
340}
341static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
342
343static ssize_t last_failed_errno_show(struct kobject *kobj,
344 struct kobj_attribute *attr, char *buf)
345{
346 int index;
347 int last_failed_errno;
348
349 index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
350 index %= REC_FAILED_NUM;
351 last_failed_errno = suspend_stats.errno[index];
352
353 return sprintf(buf, "%d\n", last_failed_errno);
354}
355static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
356
357static ssize_t last_failed_step_show(struct kobject *kobj,
358 struct kobj_attribute *attr, char *buf)
359{
360 int index;
361 enum suspend_stat_step step;
362 char *last_failed_step = NULL;
363
364 index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
365 index %= REC_FAILED_NUM;
366 step = suspend_stats.failed_steps[index];
367 last_failed_step = suspend_step_name(step);
368
369 return sprintf(buf, "%s\n", last_failed_step);
370}
371static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
372
373static struct attribute *suspend_attrs[] = {
374 &success.attr,
375 &fail.attr,
376 &failed_freeze.attr,
377 &failed_prepare.attr,
378 &failed_suspend.attr,
379 &failed_suspend_late.attr,
380 &failed_suspend_noirq.attr,
381 &failed_resume.attr,
382 &failed_resume_early.attr,
383 &failed_resume_noirq.attr,
384 &last_failed_dev.attr,
385 &last_failed_errno.attr,
386 &last_failed_step.attr,
387 NULL,
388};
389
390static struct attribute_group suspend_attr_group = {
391 .name = "suspend_stats",
392 .attrs = suspend_attrs,
393};
394
395#ifdef CONFIG_DEBUG_FS
396static int suspend_stats_show(struct seq_file *s, void *unused)
397{
398 int i, index, last_dev, last_errno, last_step;
399
400 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
401 last_dev %= REC_FAILED_NUM;
402 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
403 last_errno %= REC_FAILED_NUM;
404 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
405 last_step %= REC_FAILED_NUM;
406 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
407 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
408 "success", suspend_stats.success,
409 "fail", suspend_stats.fail,
410 "failed_freeze", suspend_stats.failed_freeze,
411 "failed_prepare", suspend_stats.failed_prepare,
412 "failed_suspend", suspend_stats.failed_suspend,
413 "failed_suspend_late",
414 suspend_stats.failed_suspend_late,
415 "failed_suspend_noirq",
416 suspend_stats.failed_suspend_noirq,
417 "failed_resume", suspend_stats.failed_resume,
418 "failed_resume_early",
419 suspend_stats.failed_resume_early,
420 "failed_resume_noirq",
421 suspend_stats.failed_resume_noirq);
422 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
423 suspend_stats.failed_devs[last_dev]);
424 for (i = 1; i < REC_FAILED_NUM; i++) {
425 index = last_dev + REC_FAILED_NUM - i;
426 index %= REC_FAILED_NUM;
427 seq_printf(s, "\t\t\t%-s\n",
428 suspend_stats.failed_devs[index]);
429 }
430 seq_printf(s, " last_failed_errno:\t%-d\n",
431 suspend_stats.errno[last_errno]);
432 for (i = 1; i < REC_FAILED_NUM; i++) {
433 index = last_errno + REC_FAILED_NUM - i;
434 index %= REC_FAILED_NUM;
435 seq_printf(s, "\t\t\t%-d\n",
436 suspend_stats.errno[index]);
437 }
438 seq_printf(s, " last_failed_step:\t%-s\n",
439 suspend_step_name(
440 suspend_stats.failed_steps[last_step]));
441 for (i = 1; i < REC_FAILED_NUM; i++) {
442 index = last_step + REC_FAILED_NUM - i;
443 index %= REC_FAILED_NUM;
444 seq_printf(s, "\t\t\t%-s\n",
445 suspend_step_name(
446 suspend_stats.failed_steps[index]));
447 }
448
449 return 0;
450}
451DEFINE_SHOW_ATTRIBUTE(suspend_stats);
452
453static int __init pm_debugfs_init(void)
454{
455 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
456 NULL, NULL, &suspend_stats_fops);
457 return 0;
458}
459
460late_initcall(pm_debugfs_init);
461#endif /* CONFIG_DEBUG_FS */
462
463#endif /* CONFIG_PM_SLEEP */
464
465#ifdef CONFIG_PM_SLEEP_DEBUG
466/*
467 * pm_print_times: print time taken by devices to suspend and resume.
468 *
469 * show() returns whether printing of suspend and resume times is enabled.
470 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
471 */
472bool pm_print_times_enabled;
473
474static ssize_t pm_print_times_show(struct kobject *kobj,
475 struct kobj_attribute *attr, char *buf)
476{
477 return sprintf(buf, "%d\n", pm_print_times_enabled);
478}
479
480static ssize_t pm_print_times_store(struct kobject *kobj,
481 struct kobj_attribute *attr,
482 const char *buf, size_t n)
483{
484 unsigned long val;
485
486 if (kstrtoul(buf, 10, &val))
487 return -EINVAL;
488
489 if (val > 1)
490 return -EINVAL;
491
492 pm_print_times_enabled = !!val;
493 return n;
494}
495
496power_attr(pm_print_times);
497
498static inline void pm_print_times_init(void)
499{
500 pm_print_times_enabled = !!initcall_debug;
501}
502
503static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
504 struct kobj_attribute *attr,
505 char *buf)
506{
507 return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA;
508}
509
510power_attr_ro(pm_wakeup_irq);
511
512bool pm_debug_messages_on __read_mostly;
513
514static ssize_t pm_debug_messages_show(struct kobject *kobj,
515 struct kobj_attribute *attr, char *buf)
516{
517 return sprintf(buf, "%d\n", pm_debug_messages_on);
518}
519
520static ssize_t pm_debug_messages_store(struct kobject *kobj,
521 struct kobj_attribute *attr,
522 const char *buf, size_t n)
523{
524 unsigned long val;
525
526 if (kstrtoul(buf, 10, &val))
527 return -EINVAL;
528
529 if (val > 1)
530 return -EINVAL;
531
532 pm_debug_messages_on = !!val;
533 return n;
534}
535
536power_attr(pm_debug_messages);
537
538static int __init pm_debug_messages_setup(char *str)
539{
540 pm_debug_messages_on = true;
541 return 1;
542}
543__setup("pm_debug_messages", pm_debug_messages_setup);
544
545/**
546 * __pm_pr_dbg - Print a suspend debug message to the kernel log.
547 * @defer: Whether or not to use printk_deferred() to print the message.
548 * @fmt: Message format.
549 *
550 * The message will be emitted if enabled through the pm_debug_messages
551 * sysfs attribute.
552 */
553void __pm_pr_dbg(bool defer, const char *fmt, ...)
554{
555 struct va_format vaf;
556 va_list args;
557
558 if (!pm_debug_messages_on)
559 return;
560
561 va_start(args, fmt);
562
563 vaf.fmt = fmt;
564 vaf.va = &args;
565
566 if (defer)
567 printk_deferred(KERN_DEBUG "PM: %pV", &vaf);
568 else
569 printk(KERN_DEBUG "PM: %pV", &vaf);
570
571 va_end(args);
572}
573
574#else /* !CONFIG_PM_SLEEP_DEBUG */
575static inline void pm_print_times_init(void) {}
576#endif /* CONFIG_PM_SLEEP_DEBUG */
577
578struct kobject *power_kobj;
579
580/**
581 * state - control system sleep states.
582 *
583 * show() returns available sleep state labels, which may be "mem", "standby",
584 * "freeze" and "disk" (hibernation).
585 * See Documentation/admin-guide/pm/sleep-states.rst for a description of
586 * what they mean.
587 *
588 * store() accepts one of those strings, translates it into the proper
589 * enumerated value, and initiates a suspend transition.
590 */
591static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
592 char *buf)
593{
594 char *s = buf;
595#ifdef CONFIG_SUSPEND
596 suspend_state_t i;
597
598 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
599 if (pm_states[i])
600 s += sprintf(s,"%s ", pm_states[i]);
601
602#endif
603 if (hibernation_available())
604 s += sprintf(s, "disk ");
605 if (s != buf)
606 /* convert the last space to a newline */
607 *(s-1) = '\n';
608 return (s - buf);
609}
610
611static suspend_state_t decode_state(const char *buf, size_t n)
612{
613#ifdef CONFIG_SUSPEND
614 suspend_state_t state;
615#endif
616 char *p;
617 int len;
618
619 p = memchr(buf, '\n', n);
620 len = p ? p - buf : n;
621
622 /* Check hibernation first. */
623 if (len == 4 && str_has_prefix(buf, "disk"))
624 return PM_SUSPEND_MAX;
625
626#ifdef CONFIG_SUSPEND
627 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
628 const char *label = pm_states[state];
629
630 if (label && len == strlen(label) && !strncmp(buf, label, len))
631 return state;
632 }
633#endif
634
635 return PM_SUSPEND_ON;
636}
637
638static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
639 const char *buf, size_t n)
640{
641 suspend_state_t state;
642 int error;
643
644 error = pm_autosleep_lock();
645 if (error)
646 return error;
647
648 if (pm_autosleep_state() > PM_SUSPEND_ON) {
649 error = -EBUSY;
650 goto out;
651 }
652
653 state = decode_state(buf, n);
654 if (state < PM_SUSPEND_MAX) {
655 if (state == PM_SUSPEND_MEM)
656 state = mem_sleep_current;
657
658 error = pm_suspend(state);
659 } else if (state == PM_SUSPEND_MAX) {
660 error = hibernate();
661 } else {
662 error = -EINVAL;
663 }
664
665 out:
666 pm_autosleep_unlock();
667 return error ? error : n;
668}
669
670power_attr(state);
671
672#ifdef CONFIG_PM_SLEEP
673/*
674 * The 'wakeup_count' attribute, along with the functions defined in
675 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
676 * handled in a non-racy way.
677 *
678 * If a wakeup event occurs when the system is in a sleep state, it simply is
679 * woken up. In turn, if an event that would wake the system up from a sleep
680 * state occurs when it is undergoing a transition to that sleep state, the
681 * transition should be aborted. Moreover, if such an event occurs when the
682 * system is in the working state, an attempt to start a transition to the
683 * given sleep state should fail during certain period after the detection of
684 * the event. Using the 'state' attribute alone is not sufficient to satisfy
685 * these requirements, because a wakeup event may occur exactly when 'state'
686 * is being written to and may be delivered to user space right before it is
687 * frozen, so the event will remain only partially processed until the system is
688 * woken up by another event. In particular, it won't cause the transition to
689 * a sleep state to be aborted.
690 *
691 * This difficulty may be overcome if user space uses 'wakeup_count' before
692 * writing to 'state'. It first should read from 'wakeup_count' and store
693 * the read value. Then, after carrying out its own preparations for the system
694 * transition to a sleep state, it should write the stored value to
695 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
696 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
697 * is allowed to write to 'state', but the transition will be aborted if there
698 * are any wakeup events detected after 'wakeup_count' was written to.
699 */
700
701static ssize_t wakeup_count_show(struct kobject *kobj,
702 struct kobj_attribute *attr,
703 char *buf)
704{
705 unsigned int val;
706
707 return pm_get_wakeup_count(&val, true) ?
708 sprintf(buf, "%u\n", val) : -EINTR;
709}
710
711static ssize_t wakeup_count_store(struct kobject *kobj,
712 struct kobj_attribute *attr,
713 const char *buf, size_t n)
714{
715 unsigned int val;
716 int error;
717
718 error = pm_autosleep_lock();
719 if (error)
720 return error;
721
722 if (pm_autosleep_state() > PM_SUSPEND_ON) {
723 error = -EBUSY;
724 goto out;
725 }
726
727 error = -EINVAL;
728 if (sscanf(buf, "%u", &val) == 1) {
729 if (pm_save_wakeup_count(val))
730 error = n;
731 else
732 pm_print_active_wakeup_sources();
733 }
734
735 out:
736 pm_autosleep_unlock();
737 return error;
738}
739
740power_attr(wakeup_count);
741
742#ifdef CONFIG_PM_AUTOSLEEP
743static ssize_t autosleep_show(struct kobject *kobj,
744 struct kobj_attribute *attr,
745 char *buf)
746{
747 suspend_state_t state = pm_autosleep_state();
748
749 if (state == PM_SUSPEND_ON)
750 return sprintf(buf, "off\n");
751
752#ifdef CONFIG_SUSPEND
753 if (state < PM_SUSPEND_MAX)
754 return sprintf(buf, "%s\n", pm_states[state] ?
755 pm_states[state] : "error");
756#endif
757#ifdef CONFIG_HIBERNATION
758 return sprintf(buf, "disk\n");
759#else
760 return sprintf(buf, "error");
761#endif
762}
763
764static ssize_t autosleep_store(struct kobject *kobj,
765 struct kobj_attribute *attr,
766 const char *buf, size_t n)
767{
768 suspend_state_t state = decode_state(buf, n);
769 int error;
770
771 if (state == PM_SUSPEND_ON
772 && strcmp(buf, "off") && strcmp(buf, "off\n"))
773 return -EINVAL;
774
775 if (state == PM_SUSPEND_MEM)
776 state = mem_sleep_current;
777
778 error = pm_autosleep_set_state(state);
779 return error ? error : n;
780}
781
782power_attr(autosleep);
783#endif /* CONFIG_PM_AUTOSLEEP */
784
785#ifdef CONFIG_PM_WAKELOCKS
786static ssize_t wake_lock_show(struct kobject *kobj,
787 struct kobj_attribute *attr,
788 char *buf)
789{
790 return pm_show_wakelocks(buf, true);
791}
792
793static ssize_t wake_lock_store(struct kobject *kobj,
794 struct kobj_attribute *attr,
795 const char *buf, size_t n)
796{
797 int error = pm_wake_lock(buf);
798 return error ? error : n;
799}
800
801power_attr(wake_lock);
802
803static ssize_t wake_unlock_show(struct kobject *kobj,
804 struct kobj_attribute *attr,
805 char *buf)
806{
807 return pm_show_wakelocks(buf, false);
808}
809
810static ssize_t wake_unlock_store(struct kobject *kobj,
811 struct kobj_attribute *attr,
812 const char *buf, size_t n)
813{
814 int error = pm_wake_unlock(buf);
815 return error ? error : n;
816}
817
818power_attr(wake_unlock);
819
820#endif /* CONFIG_PM_WAKELOCKS */
821#endif /* CONFIG_PM_SLEEP */
822
823#ifdef CONFIG_PM_TRACE
824int pm_trace_enabled;
825
826static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
827 char *buf)
828{
829 return sprintf(buf, "%d\n", pm_trace_enabled);
830}
831
832static ssize_t
833pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
834 const char *buf, size_t n)
835{
836 int val;
837
838 if (sscanf(buf, "%d", &val) == 1) {
839 pm_trace_enabled = !!val;
840 if (pm_trace_enabled) {
841 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
842 "PM: Correct system time has to be restored manually after resume.\n");
843 }
844 return n;
845 }
846 return -EINVAL;
847}
848
849power_attr(pm_trace);
850
851static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
852 struct kobj_attribute *attr,
853 char *buf)
854{
855 return show_trace_dev_match(buf, PAGE_SIZE);
856}
857
858power_attr_ro(pm_trace_dev_match);
859
860#endif /* CONFIG_PM_TRACE */
861
862#ifdef CONFIG_FREEZER
863static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
864 struct kobj_attribute *attr, char *buf)
865{
866 return sprintf(buf, "%u\n", freeze_timeout_msecs);
867}
868
869static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
870 struct kobj_attribute *attr,
871 const char *buf, size_t n)
872{
873 unsigned long val;
874
875 if (kstrtoul(buf, 10, &val))
876 return -EINVAL;
877
878 freeze_timeout_msecs = val;
879 return n;
880}
881
882power_attr(pm_freeze_timeout);
883
884#endif /* CONFIG_FREEZER*/
885
886static struct attribute * g[] = {
887 &state_attr.attr,
888#ifdef CONFIG_PM_TRACE
889 &pm_trace_attr.attr,
890 &pm_trace_dev_match_attr.attr,
891#endif
892#ifdef CONFIG_PM_SLEEP
893 &pm_async_attr.attr,
894 &wakeup_count_attr.attr,
895#ifdef CONFIG_SUSPEND
896 &mem_sleep_attr.attr,
897 &sync_on_suspend_attr.attr,
898#endif
899#ifdef CONFIG_PM_AUTOSLEEP
900 &autosleep_attr.attr,
901#endif
902#ifdef CONFIG_PM_WAKELOCKS
903 &wake_lock_attr.attr,
904 &wake_unlock_attr.attr,
905#endif
906#ifdef CONFIG_PM_SLEEP_DEBUG
907 &pm_test_attr.attr,
908 &pm_print_times_attr.attr,
909 &pm_wakeup_irq_attr.attr,
910 &pm_debug_messages_attr.attr,
911#endif
912#endif
913#ifdef CONFIG_FREEZER
914 &pm_freeze_timeout_attr.attr,
915#endif
916 NULL,
917};
918
919static const struct attribute_group attr_group = {
920 .attrs = g,
921};
922
923static const struct attribute_group *attr_groups[] = {
924 &attr_group,
925#ifdef CONFIG_PM_SLEEP
926 &suspend_attr_group,
927#endif
928 NULL,
929};
930
931struct workqueue_struct *pm_wq;
932EXPORT_SYMBOL_GPL(pm_wq);
933
934static int __init pm_start_workqueue(void)
935{
936 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
937
938 return pm_wq ? 0 : -ENOMEM;
939}
940
941static int __init pm_init(void)
942{
943 int error = pm_start_workqueue();
944 if (error)
945 return error;
946 hibernate_image_size_init();
947 hibernate_reserved_size_init();
948 pm_states_init();
949 power_kobj = kobject_create_and_add("power", NULL);
950 if (!power_kobj)
951 return -ENOMEM;
952 error = sysfs_create_groups(power_kobj, attr_groups);
953 if (error)
954 return error;
955 pm_print_times_init();
956 return pm_autosleep_init();
957}
958
959core_initcall(pm_init);
1/*
2 * kernel/power/main.c - PM subsystem core functionality.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 *
7 * This file is released under the GPLv2
8 *
9 */
10
11#include <linux/export.h>
12#include <linux/kobject.h>
13#include <linux/string.h>
14#include <linux/resume-trace.h>
15#include <linux/workqueue.h>
16#include <linux/debugfs.h>
17#include <linux/seq_file.h>
18
19#include "power.h"
20
21DEFINE_MUTEX(pm_mutex);
22
23#ifdef CONFIG_PM_SLEEP
24
25/* Routines for PM-transition notifications */
26
27static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
28
29int register_pm_notifier(struct notifier_block *nb)
30{
31 return blocking_notifier_chain_register(&pm_chain_head, nb);
32}
33EXPORT_SYMBOL_GPL(register_pm_notifier);
34
35int unregister_pm_notifier(struct notifier_block *nb)
36{
37 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
38}
39EXPORT_SYMBOL_GPL(unregister_pm_notifier);
40
41int pm_notifier_call_chain(unsigned long val)
42{
43 int ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL);
44
45 return notifier_to_errno(ret);
46}
47
48/* If set, devices may be suspended and resumed asynchronously. */
49int pm_async_enabled = 1;
50
51static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
52 char *buf)
53{
54 return sprintf(buf, "%d\n", pm_async_enabled);
55}
56
57static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
58 const char *buf, size_t n)
59{
60 unsigned long val;
61
62 if (kstrtoul(buf, 10, &val))
63 return -EINVAL;
64
65 if (val > 1)
66 return -EINVAL;
67
68 pm_async_enabled = val;
69 return n;
70}
71
72power_attr(pm_async);
73
74#ifdef CONFIG_PM_DEBUG
75int pm_test_level = TEST_NONE;
76
77static const char * const pm_tests[__TEST_AFTER_LAST] = {
78 [TEST_NONE] = "none",
79 [TEST_CORE] = "core",
80 [TEST_CPUS] = "processors",
81 [TEST_PLATFORM] = "platform",
82 [TEST_DEVICES] = "devices",
83 [TEST_FREEZER] = "freezer",
84};
85
86static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
87 char *buf)
88{
89 char *s = buf;
90 int level;
91
92 for (level = TEST_FIRST; level <= TEST_MAX; level++)
93 if (pm_tests[level]) {
94 if (level == pm_test_level)
95 s += sprintf(s, "[%s] ", pm_tests[level]);
96 else
97 s += sprintf(s, "%s ", pm_tests[level]);
98 }
99
100 if (s != buf)
101 /* convert the last space to a newline */
102 *(s-1) = '\n';
103
104 return (s - buf);
105}
106
107static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
108 const char *buf, size_t n)
109{
110 const char * const *s;
111 int level;
112 char *p;
113 int len;
114 int error = -EINVAL;
115
116 p = memchr(buf, '\n', n);
117 len = p ? p - buf : n;
118
119 lock_system_sleep();
120
121 level = TEST_FIRST;
122 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
123 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
124 pm_test_level = level;
125 error = 0;
126 break;
127 }
128
129 unlock_system_sleep();
130
131 return error ? error : n;
132}
133
134power_attr(pm_test);
135#endif /* CONFIG_PM_DEBUG */
136
137#ifdef CONFIG_DEBUG_FS
138static char *suspend_step_name(enum suspend_stat_step step)
139{
140 switch (step) {
141 case SUSPEND_FREEZE:
142 return "freeze";
143 case SUSPEND_PREPARE:
144 return "prepare";
145 case SUSPEND_SUSPEND:
146 return "suspend";
147 case SUSPEND_SUSPEND_NOIRQ:
148 return "suspend_noirq";
149 case SUSPEND_RESUME_NOIRQ:
150 return "resume_noirq";
151 case SUSPEND_RESUME:
152 return "resume";
153 default:
154 return "";
155 }
156}
157
158static int suspend_stats_show(struct seq_file *s, void *unused)
159{
160 int i, index, last_dev, last_errno, last_step;
161
162 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
163 last_dev %= REC_FAILED_NUM;
164 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
165 last_errno %= REC_FAILED_NUM;
166 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
167 last_step %= REC_FAILED_NUM;
168 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
169 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
170 "success", suspend_stats.success,
171 "fail", suspend_stats.fail,
172 "failed_freeze", suspend_stats.failed_freeze,
173 "failed_prepare", suspend_stats.failed_prepare,
174 "failed_suspend", suspend_stats.failed_suspend,
175 "failed_suspend_late",
176 suspend_stats.failed_suspend_late,
177 "failed_suspend_noirq",
178 suspend_stats.failed_suspend_noirq,
179 "failed_resume", suspend_stats.failed_resume,
180 "failed_resume_early",
181 suspend_stats.failed_resume_early,
182 "failed_resume_noirq",
183 suspend_stats.failed_resume_noirq);
184 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
185 suspend_stats.failed_devs[last_dev]);
186 for (i = 1; i < REC_FAILED_NUM; i++) {
187 index = last_dev + REC_FAILED_NUM - i;
188 index %= REC_FAILED_NUM;
189 seq_printf(s, "\t\t\t%-s\n",
190 suspend_stats.failed_devs[index]);
191 }
192 seq_printf(s, " last_failed_errno:\t%-d\n",
193 suspend_stats.errno[last_errno]);
194 for (i = 1; i < REC_FAILED_NUM; i++) {
195 index = last_errno + REC_FAILED_NUM - i;
196 index %= REC_FAILED_NUM;
197 seq_printf(s, "\t\t\t%-d\n",
198 suspend_stats.errno[index]);
199 }
200 seq_printf(s, " last_failed_step:\t%-s\n",
201 suspend_step_name(
202 suspend_stats.failed_steps[last_step]));
203 for (i = 1; i < REC_FAILED_NUM; i++) {
204 index = last_step + REC_FAILED_NUM - i;
205 index %= REC_FAILED_NUM;
206 seq_printf(s, "\t\t\t%-s\n",
207 suspend_step_name(
208 suspend_stats.failed_steps[index]));
209 }
210
211 return 0;
212}
213
214static int suspend_stats_open(struct inode *inode, struct file *file)
215{
216 return single_open(file, suspend_stats_show, NULL);
217}
218
219static const struct file_operations suspend_stats_operations = {
220 .open = suspend_stats_open,
221 .read = seq_read,
222 .llseek = seq_lseek,
223 .release = single_release,
224};
225
226static int __init pm_debugfs_init(void)
227{
228 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
229 NULL, NULL, &suspend_stats_operations);
230 return 0;
231}
232
233late_initcall(pm_debugfs_init);
234#endif /* CONFIG_DEBUG_FS */
235
236#endif /* CONFIG_PM_SLEEP */
237
238#ifdef CONFIG_PM_SLEEP_DEBUG
239/*
240 * pm_print_times: print time taken by devices to suspend and resume.
241 *
242 * show() returns whether printing of suspend and resume times is enabled.
243 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
244 */
245bool pm_print_times_enabled;
246
247static ssize_t pm_print_times_show(struct kobject *kobj,
248 struct kobj_attribute *attr, char *buf)
249{
250 return sprintf(buf, "%d\n", pm_print_times_enabled);
251}
252
253static ssize_t pm_print_times_store(struct kobject *kobj,
254 struct kobj_attribute *attr,
255 const char *buf, size_t n)
256{
257 unsigned long val;
258
259 if (kstrtoul(buf, 10, &val))
260 return -EINVAL;
261
262 if (val > 1)
263 return -EINVAL;
264
265 pm_print_times_enabled = !!val;
266 return n;
267}
268
269power_attr(pm_print_times);
270
271static inline void pm_print_times_init(void)
272{
273 pm_print_times_enabled = !!initcall_debug;
274}
275#else /* !CONFIG_PP_SLEEP_DEBUG */
276static inline void pm_print_times_init(void) {}
277#endif /* CONFIG_PM_SLEEP_DEBUG */
278
279struct kobject *power_kobj;
280
281/**
282 * state - control system power state.
283 *
284 * show() returns what states are supported, which is hard-coded to
285 * 'freeze' (Low-Power Idle), 'standby' (Power-On Suspend),
286 * 'mem' (Suspend-to-RAM), and 'disk' (Suspend-to-Disk).
287 *
288 * store() accepts one of those strings, translates it into the
289 * proper enumerated value, and initiates a suspend transition.
290 */
291static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
292 char *buf)
293{
294 char *s = buf;
295#ifdef CONFIG_SUSPEND
296 int i;
297
298 for (i = 0; i < PM_SUSPEND_MAX; i++) {
299 if (pm_states[i] && valid_state(i))
300 s += sprintf(s,"%s ", pm_states[i]);
301 }
302#endif
303#ifdef CONFIG_HIBERNATION
304 s += sprintf(s, "%s\n", "disk");
305#else
306 if (s != buf)
307 /* convert the last space to a newline */
308 *(s-1) = '\n';
309#endif
310 return (s - buf);
311}
312
313static suspend_state_t decode_state(const char *buf, size_t n)
314{
315#ifdef CONFIG_SUSPEND
316 suspend_state_t state = PM_SUSPEND_MIN;
317 const char * const *s;
318#endif
319 char *p;
320 int len;
321
322 p = memchr(buf, '\n', n);
323 len = p ? p - buf : n;
324
325 /* Check hibernation first. */
326 if (len == 4 && !strncmp(buf, "disk", len))
327 return PM_SUSPEND_MAX;
328
329#ifdef CONFIG_SUSPEND
330 for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++)
331 if (*s && len == strlen(*s) && !strncmp(buf, *s, len))
332 return state;
333#endif
334
335 return PM_SUSPEND_ON;
336}
337
338static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
339 const char *buf, size_t n)
340{
341 suspend_state_t state;
342 int error;
343
344 error = pm_autosleep_lock();
345 if (error)
346 return error;
347
348 if (pm_autosleep_state() > PM_SUSPEND_ON) {
349 error = -EBUSY;
350 goto out;
351 }
352
353 state = decode_state(buf, n);
354 if (state < PM_SUSPEND_MAX)
355 error = pm_suspend(state);
356 else if (state == PM_SUSPEND_MAX)
357 error = hibernate();
358 else
359 error = -EINVAL;
360
361 out:
362 pm_autosleep_unlock();
363 return error ? error : n;
364}
365
366power_attr(state);
367
368#ifdef CONFIG_PM_SLEEP
369/*
370 * The 'wakeup_count' attribute, along with the functions defined in
371 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
372 * handled in a non-racy way.
373 *
374 * If a wakeup event occurs when the system is in a sleep state, it simply is
375 * woken up. In turn, if an event that would wake the system up from a sleep
376 * state occurs when it is undergoing a transition to that sleep state, the
377 * transition should be aborted. Moreover, if such an event occurs when the
378 * system is in the working state, an attempt to start a transition to the
379 * given sleep state should fail during certain period after the detection of
380 * the event. Using the 'state' attribute alone is not sufficient to satisfy
381 * these requirements, because a wakeup event may occur exactly when 'state'
382 * is being written to and may be delivered to user space right before it is
383 * frozen, so the event will remain only partially processed until the system is
384 * woken up by another event. In particular, it won't cause the transition to
385 * a sleep state to be aborted.
386 *
387 * This difficulty may be overcome if user space uses 'wakeup_count' before
388 * writing to 'state'. It first should read from 'wakeup_count' and store
389 * the read value. Then, after carrying out its own preparations for the system
390 * transition to a sleep state, it should write the stored value to
391 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
392 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
393 * is allowed to write to 'state', but the transition will be aborted if there
394 * are any wakeup events detected after 'wakeup_count' was written to.
395 */
396
397static ssize_t wakeup_count_show(struct kobject *kobj,
398 struct kobj_attribute *attr,
399 char *buf)
400{
401 unsigned int val;
402
403 return pm_get_wakeup_count(&val, true) ?
404 sprintf(buf, "%u\n", val) : -EINTR;
405}
406
407static ssize_t wakeup_count_store(struct kobject *kobj,
408 struct kobj_attribute *attr,
409 const char *buf, size_t n)
410{
411 unsigned int val;
412 int error;
413
414 error = pm_autosleep_lock();
415 if (error)
416 return error;
417
418 if (pm_autosleep_state() > PM_SUSPEND_ON) {
419 error = -EBUSY;
420 goto out;
421 }
422
423 error = -EINVAL;
424 if (sscanf(buf, "%u", &val) == 1) {
425 if (pm_save_wakeup_count(val))
426 error = n;
427 else
428 pm_print_active_wakeup_sources();
429 }
430
431 out:
432 pm_autosleep_unlock();
433 return error;
434}
435
436power_attr(wakeup_count);
437
438#ifdef CONFIG_PM_AUTOSLEEP
439static ssize_t autosleep_show(struct kobject *kobj,
440 struct kobj_attribute *attr,
441 char *buf)
442{
443 suspend_state_t state = pm_autosleep_state();
444
445 if (state == PM_SUSPEND_ON)
446 return sprintf(buf, "off\n");
447
448#ifdef CONFIG_SUSPEND
449 if (state < PM_SUSPEND_MAX)
450 return sprintf(buf, "%s\n", valid_state(state) ?
451 pm_states[state] : "error");
452#endif
453#ifdef CONFIG_HIBERNATION
454 return sprintf(buf, "disk\n");
455#else
456 return sprintf(buf, "error");
457#endif
458}
459
460static ssize_t autosleep_store(struct kobject *kobj,
461 struct kobj_attribute *attr,
462 const char *buf, size_t n)
463{
464 suspend_state_t state = decode_state(buf, n);
465 int error;
466
467 if (state == PM_SUSPEND_ON
468 && strcmp(buf, "off") && strcmp(buf, "off\n"))
469 return -EINVAL;
470
471 error = pm_autosleep_set_state(state);
472 return error ? error : n;
473}
474
475power_attr(autosleep);
476#endif /* CONFIG_PM_AUTOSLEEP */
477
478#ifdef CONFIG_PM_WAKELOCKS
479static ssize_t wake_lock_show(struct kobject *kobj,
480 struct kobj_attribute *attr,
481 char *buf)
482{
483 return pm_show_wakelocks(buf, true);
484}
485
486static ssize_t wake_lock_store(struct kobject *kobj,
487 struct kobj_attribute *attr,
488 const char *buf, size_t n)
489{
490 int error = pm_wake_lock(buf);
491 return error ? error : n;
492}
493
494power_attr(wake_lock);
495
496static ssize_t wake_unlock_show(struct kobject *kobj,
497 struct kobj_attribute *attr,
498 char *buf)
499{
500 return pm_show_wakelocks(buf, false);
501}
502
503static ssize_t wake_unlock_store(struct kobject *kobj,
504 struct kobj_attribute *attr,
505 const char *buf, size_t n)
506{
507 int error = pm_wake_unlock(buf);
508 return error ? error : n;
509}
510
511power_attr(wake_unlock);
512
513#endif /* CONFIG_PM_WAKELOCKS */
514#endif /* CONFIG_PM_SLEEP */
515
516#ifdef CONFIG_PM_TRACE
517int pm_trace_enabled;
518
519static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
520 char *buf)
521{
522 return sprintf(buf, "%d\n", pm_trace_enabled);
523}
524
525static ssize_t
526pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
527 const char *buf, size_t n)
528{
529 int val;
530
531 if (sscanf(buf, "%d", &val) == 1) {
532 pm_trace_enabled = !!val;
533 if (pm_trace_enabled) {
534 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
535 "PM: Correct system time has to be restored manually after resume.\n");
536 }
537 return n;
538 }
539 return -EINVAL;
540}
541
542power_attr(pm_trace);
543
544static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
545 struct kobj_attribute *attr,
546 char *buf)
547{
548 return show_trace_dev_match(buf, PAGE_SIZE);
549}
550
551static ssize_t
552pm_trace_dev_match_store(struct kobject *kobj, struct kobj_attribute *attr,
553 const char *buf, size_t n)
554{
555 return -EINVAL;
556}
557
558power_attr(pm_trace_dev_match);
559
560#endif /* CONFIG_PM_TRACE */
561
562#ifdef CONFIG_FREEZER
563static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
564 struct kobj_attribute *attr, char *buf)
565{
566 return sprintf(buf, "%u\n", freeze_timeout_msecs);
567}
568
569static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
570 struct kobj_attribute *attr,
571 const char *buf, size_t n)
572{
573 unsigned long val;
574
575 if (kstrtoul(buf, 10, &val))
576 return -EINVAL;
577
578 freeze_timeout_msecs = val;
579 return n;
580}
581
582power_attr(pm_freeze_timeout);
583
584#endif /* CONFIG_FREEZER*/
585
586static struct attribute * g[] = {
587 &state_attr.attr,
588#ifdef CONFIG_PM_TRACE
589 &pm_trace_attr.attr,
590 &pm_trace_dev_match_attr.attr,
591#endif
592#ifdef CONFIG_PM_SLEEP
593 &pm_async_attr.attr,
594 &wakeup_count_attr.attr,
595#ifdef CONFIG_PM_AUTOSLEEP
596 &autosleep_attr.attr,
597#endif
598#ifdef CONFIG_PM_WAKELOCKS
599 &wake_lock_attr.attr,
600 &wake_unlock_attr.attr,
601#endif
602#ifdef CONFIG_PM_DEBUG
603 &pm_test_attr.attr,
604#endif
605#ifdef CONFIG_PM_SLEEP_DEBUG
606 &pm_print_times_attr.attr,
607#endif
608#endif
609#ifdef CONFIG_FREEZER
610 &pm_freeze_timeout_attr.attr,
611#endif
612 NULL,
613};
614
615static struct attribute_group attr_group = {
616 .attrs = g,
617};
618
619#ifdef CONFIG_PM_RUNTIME
620struct workqueue_struct *pm_wq;
621EXPORT_SYMBOL_GPL(pm_wq);
622
623static int __init pm_start_workqueue(void)
624{
625 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
626
627 return pm_wq ? 0 : -ENOMEM;
628}
629#else
630static inline int pm_start_workqueue(void) { return 0; }
631#endif
632
633static int __init pm_init(void)
634{
635 int error = pm_start_workqueue();
636 if (error)
637 return error;
638 hibernate_image_size_init();
639 hibernate_reserved_size_init();
640 power_kobj = kobject_create_and_add("power", NULL);
641 if (!power_kobj)
642 return -ENOMEM;
643 error = sysfs_create_group(power_kobj, &attr_group);
644 if (error)
645 return error;
646 pm_print_times_init();
647 return pm_autosleep_init();
648}
649
650core_initcall(pm_init);