Loading...
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
24unsigned int lock_system_sleep(void)
25{
26 unsigned int flags = current->flags;
27 current->flags |= PF_NOFREEZE;
28 mutex_lock(&system_transition_mutex);
29 return flags;
30}
31EXPORT_SYMBOL_GPL(lock_system_sleep);
32
33void unlock_system_sleep(unsigned int flags)
34{
35 /*
36 * Don't use freezer_count() because we don't want the call to
37 * try_to_freeze() here.
38 *
39 * Reason:
40 * Fundamentally, we just don't need it, because freezing condition
41 * doesn't come into effect until we release the
42 * system_transition_mutex lock, since the freezer always works with
43 * system_transition_mutex held.
44 *
45 * More importantly, in the case of hibernation,
46 * unlock_system_sleep() gets called in snapshot_read() and
47 * snapshot_write() when the freezing condition is still in effect.
48 * Which means, if we use try_to_freeze() here, it would make them
49 * enter the refrigerator, thus causing hibernation to lockup.
50 */
51 if (!(flags & PF_NOFREEZE))
52 current->flags &= ~PF_NOFREEZE;
53 mutex_unlock(&system_transition_mutex);
54}
55EXPORT_SYMBOL_GPL(unlock_system_sleep);
56
57void ksys_sync_helper(void)
58{
59 ktime_t start;
60 long elapsed_msecs;
61
62 start = ktime_get();
63 ksys_sync();
64 elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
65 pr_info("Filesystems sync: %ld.%03ld seconds\n",
66 elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
67}
68EXPORT_SYMBOL_GPL(ksys_sync_helper);
69
70/* Routines for PM-transition notifications */
71
72static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
73
74int register_pm_notifier(struct notifier_block *nb)
75{
76 return blocking_notifier_chain_register(&pm_chain_head, nb);
77}
78EXPORT_SYMBOL_GPL(register_pm_notifier);
79
80int unregister_pm_notifier(struct notifier_block *nb)
81{
82 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
83}
84EXPORT_SYMBOL_GPL(unregister_pm_notifier);
85
86int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down)
87{
88 int ret;
89
90 ret = blocking_notifier_call_chain_robust(&pm_chain_head, val_up, val_down, NULL);
91
92 return notifier_to_errno(ret);
93}
94
95int pm_notifier_call_chain(unsigned long val)
96{
97 return blocking_notifier_call_chain(&pm_chain_head, val, NULL);
98}
99
100/* If set, devices may be suspended and resumed asynchronously. */
101int pm_async_enabled = 1;
102
103static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
104 char *buf)
105{
106 return sprintf(buf, "%d\n", pm_async_enabled);
107}
108
109static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
110 const char *buf, size_t n)
111{
112 unsigned long val;
113
114 if (kstrtoul(buf, 10, &val))
115 return -EINVAL;
116
117 if (val > 1)
118 return -EINVAL;
119
120 pm_async_enabled = val;
121 return n;
122}
123
124power_attr(pm_async);
125
126#ifdef CONFIG_SUSPEND
127static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
128 char *buf)
129{
130 char *s = buf;
131 suspend_state_t i;
132
133 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) {
134 if (i >= PM_SUSPEND_MEM && cxl_mem_active())
135 continue;
136 if (mem_sleep_states[i]) {
137 const char *label = mem_sleep_states[i];
138
139 if (mem_sleep_current == i)
140 s += sprintf(s, "[%s] ", label);
141 else
142 s += sprintf(s, "%s ", label);
143 }
144 }
145
146 /* Convert the last space to a newline if needed. */
147 if (s != buf)
148 *(s-1) = '\n';
149
150 return (s - buf);
151}
152
153static suspend_state_t decode_suspend_state(const char *buf, size_t n)
154{
155 suspend_state_t state;
156 char *p;
157 int len;
158
159 p = memchr(buf, '\n', n);
160 len = p ? p - buf : n;
161
162 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
163 const char *label = mem_sleep_states[state];
164
165 if (label && len == strlen(label) && !strncmp(buf, label, len))
166 return state;
167 }
168
169 return PM_SUSPEND_ON;
170}
171
172static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
173 const char *buf, size_t n)
174{
175 suspend_state_t state;
176 int error;
177
178 error = pm_autosleep_lock();
179 if (error)
180 return error;
181
182 if (pm_autosleep_state() > PM_SUSPEND_ON) {
183 error = -EBUSY;
184 goto out;
185 }
186
187 state = decode_suspend_state(buf, n);
188 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
189 mem_sleep_current = state;
190 else
191 error = -EINVAL;
192
193 out:
194 pm_autosleep_unlock();
195 return error ? error : n;
196}
197
198power_attr(mem_sleep);
199
200/*
201 * sync_on_suspend: invoke ksys_sync_helper() before suspend.
202 *
203 * show() returns whether ksys_sync_helper() is invoked before suspend.
204 * store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it.
205 */
206bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC);
207
208static ssize_t sync_on_suspend_show(struct kobject *kobj,
209 struct kobj_attribute *attr, char *buf)
210{
211 return sprintf(buf, "%d\n", sync_on_suspend_enabled);
212}
213
214static ssize_t sync_on_suspend_store(struct kobject *kobj,
215 struct kobj_attribute *attr,
216 const char *buf, size_t n)
217{
218 unsigned long val;
219
220 if (kstrtoul(buf, 10, &val))
221 return -EINVAL;
222
223 if (val > 1)
224 return -EINVAL;
225
226 sync_on_suspend_enabled = !!val;
227 return n;
228}
229
230power_attr(sync_on_suspend);
231#endif /* CONFIG_SUSPEND */
232
233#ifdef CONFIG_PM_SLEEP_DEBUG
234int pm_test_level = TEST_NONE;
235
236static const char * const pm_tests[__TEST_AFTER_LAST] = {
237 [TEST_NONE] = "none",
238 [TEST_CORE] = "core",
239 [TEST_CPUS] = "processors",
240 [TEST_PLATFORM] = "platform",
241 [TEST_DEVICES] = "devices",
242 [TEST_FREEZER] = "freezer",
243};
244
245static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
246 char *buf)
247{
248 char *s = buf;
249 int level;
250
251 for (level = TEST_FIRST; level <= TEST_MAX; level++)
252 if (pm_tests[level]) {
253 if (level == pm_test_level)
254 s += sprintf(s, "[%s] ", pm_tests[level]);
255 else
256 s += sprintf(s, "%s ", pm_tests[level]);
257 }
258
259 if (s != buf)
260 /* convert the last space to a newline */
261 *(s-1) = '\n';
262
263 return (s - buf);
264}
265
266static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
267 const char *buf, size_t n)
268{
269 unsigned int sleep_flags;
270 const char * const *s;
271 int error = -EINVAL;
272 int level;
273 char *p;
274 int len;
275
276 p = memchr(buf, '\n', n);
277 len = p ? p - buf : n;
278
279 sleep_flags = lock_system_sleep();
280
281 level = TEST_FIRST;
282 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
283 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
284 pm_test_level = level;
285 error = 0;
286 break;
287 }
288
289 unlock_system_sleep(sleep_flags);
290
291 return error ? error : n;
292}
293
294power_attr(pm_test);
295#endif /* CONFIG_PM_SLEEP_DEBUG */
296
297static char *suspend_step_name(enum suspend_stat_step step)
298{
299 switch (step) {
300 case SUSPEND_FREEZE:
301 return "freeze";
302 case SUSPEND_PREPARE:
303 return "prepare";
304 case SUSPEND_SUSPEND:
305 return "suspend";
306 case SUSPEND_SUSPEND_NOIRQ:
307 return "suspend_noirq";
308 case SUSPEND_RESUME_NOIRQ:
309 return "resume_noirq";
310 case SUSPEND_RESUME:
311 return "resume";
312 default:
313 return "";
314 }
315}
316
317#define suspend_attr(_name) \
318static ssize_t _name##_show(struct kobject *kobj, \
319 struct kobj_attribute *attr, char *buf) \
320{ \
321 return sprintf(buf, "%d\n", suspend_stats._name); \
322} \
323static struct kobj_attribute _name = __ATTR_RO(_name)
324
325suspend_attr(success);
326suspend_attr(fail);
327suspend_attr(failed_freeze);
328suspend_attr(failed_prepare);
329suspend_attr(failed_suspend);
330suspend_attr(failed_suspend_late);
331suspend_attr(failed_suspend_noirq);
332suspend_attr(failed_resume);
333suspend_attr(failed_resume_early);
334suspend_attr(failed_resume_noirq);
335
336static ssize_t last_failed_dev_show(struct kobject *kobj,
337 struct kobj_attribute *attr, char *buf)
338{
339 int index;
340 char *last_failed_dev = NULL;
341
342 index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
343 index %= REC_FAILED_NUM;
344 last_failed_dev = suspend_stats.failed_devs[index];
345
346 return sprintf(buf, "%s\n", last_failed_dev);
347}
348static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
349
350static ssize_t last_failed_errno_show(struct kobject *kobj,
351 struct kobj_attribute *attr, char *buf)
352{
353 int index;
354 int last_failed_errno;
355
356 index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
357 index %= REC_FAILED_NUM;
358 last_failed_errno = suspend_stats.errno[index];
359
360 return sprintf(buf, "%d\n", last_failed_errno);
361}
362static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
363
364static ssize_t last_failed_step_show(struct kobject *kobj,
365 struct kobj_attribute *attr, char *buf)
366{
367 int index;
368 enum suspend_stat_step step;
369 char *last_failed_step = NULL;
370
371 index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
372 index %= REC_FAILED_NUM;
373 step = suspend_stats.failed_steps[index];
374 last_failed_step = suspend_step_name(step);
375
376 return sprintf(buf, "%s\n", last_failed_step);
377}
378static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
379
380static struct attribute *suspend_attrs[] = {
381 &success.attr,
382 &fail.attr,
383 &failed_freeze.attr,
384 &failed_prepare.attr,
385 &failed_suspend.attr,
386 &failed_suspend_late.attr,
387 &failed_suspend_noirq.attr,
388 &failed_resume.attr,
389 &failed_resume_early.attr,
390 &failed_resume_noirq.attr,
391 &last_failed_dev.attr,
392 &last_failed_errno.attr,
393 &last_failed_step.attr,
394 NULL,
395};
396
397static const struct attribute_group suspend_attr_group = {
398 .name = "suspend_stats",
399 .attrs = suspend_attrs,
400};
401
402#ifdef CONFIG_DEBUG_FS
403static int suspend_stats_show(struct seq_file *s, void *unused)
404{
405 int i, index, last_dev, last_errno, last_step;
406
407 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
408 last_dev %= REC_FAILED_NUM;
409 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
410 last_errno %= REC_FAILED_NUM;
411 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
412 last_step %= REC_FAILED_NUM;
413 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
414 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
415 "success", suspend_stats.success,
416 "fail", suspend_stats.fail,
417 "failed_freeze", suspend_stats.failed_freeze,
418 "failed_prepare", suspend_stats.failed_prepare,
419 "failed_suspend", suspend_stats.failed_suspend,
420 "failed_suspend_late",
421 suspend_stats.failed_suspend_late,
422 "failed_suspend_noirq",
423 suspend_stats.failed_suspend_noirq,
424 "failed_resume", suspend_stats.failed_resume,
425 "failed_resume_early",
426 suspend_stats.failed_resume_early,
427 "failed_resume_noirq",
428 suspend_stats.failed_resume_noirq);
429 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
430 suspend_stats.failed_devs[last_dev]);
431 for (i = 1; i < REC_FAILED_NUM; i++) {
432 index = last_dev + REC_FAILED_NUM - i;
433 index %= REC_FAILED_NUM;
434 seq_printf(s, "\t\t\t%-s\n",
435 suspend_stats.failed_devs[index]);
436 }
437 seq_printf(s, " last_failed_errno:\t%-d\n",
438 suspend_stats.errno[last_errno]);
439 for (i = 1; i < REC_FAILED_NUM; i++) {
440 index = last_errno + REC_FAILED_NUM - i;
441 index %= REC_FAILED_NUM;
442 seq_printf(s, "\t\t\t%-d\n",
443 suspend_stats.errno[index]);
444 }
445 seq_printf(s, " last_failed_step:\t%-s\n",
446 suspend_step_name(
447 suspend_stats.failed_steps[last_step]));
448 for (i = 1; i < REC_FAILED_NUM; i++) {
449 index = last_step + REC_FAILED_NUM - i;
450 index %= REC_FAILED_NUM;
451 seq_printf(s, "\t\t\t%-s\n",
452 suspend_step_name(
453 suspend_stats.failed_steps[index]));
454 }
455
456 return 0;
457}
458DEFINE_SHOW_ATTRIBUTE(suspend_stats);
459
460static int __init pm_debugfs_init(void)
461{
462 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
463 NULL, NULL, &suspend_stats_fops);
464 return 0;
465}
466
467late_initcall(pm_debugfs_init);
468#endif /* CONFIG_DEBUG_FS */
469
470#endif /* CONFIG_PM_SLEEP */
471
472#ifdef CONFIG_PM_SLEEP_DEBUG
473/*
474 * pm_print_times: print time taken by devices to suspend and resume.
475 *
476 * show() returns whether printing of suspend and resume times is enabled.
477 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
478 */
479bool pm_print_times_enabled;
480
481static ssize_t pm_print_times_show(struct kobject *kobj,
482 struct kobj_attribute *attr, char *buf)
483{
484 return sprintf(buf, "%d\n", pm_print_times_enabled);
485}
486
487static ssize_t pm_print_times_store(struct kobject *kobj,
488 struct kobj_attribute *attr,
489 const char *buf, size_t n)
490{
491 unsigned long val;
492
493 if (kstrtoul(buf, 10, &val))
494 return -EINVAL;
495
496 if (val > 1)
497 return -EINVAL;
498
499 pm_print_times_enabled = !!val;
500 return n;
501}
502
503power_attr(pm_print_times);
504
505static inline void pm_print_times_init(void)
506{
507 pm_print_times_enabled = !!initcall_debug;
508}
509
510static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
511 struct kobj_attribute *attr,
512 char *buf)
513{
514 if (!pm_wakeup_irq())
515 return -ENODATA;
516
517 return sprintf(buf, "%u\n", pm_wakeup_irq());
518}
519
520power_attr_ro(pm_wakeup_irq);
521
522bool pm_debug_messages_on __read_mostly;
523
524static ssize_t pm_debug_messages_show(struct kobject *kobj,
525 struct kobj_attribute *attr, char *buf)
526{
527 return sprintf(buf, "%d\n", pm_debug_messages_on);
528}
529
530static ssize_t pm_debug_messages_store(struct kobject *kobj,
531 struct kobj_attribute *attr,
532 const char *buf, size_t n)
533{
534 unsigned long val;
535
536 if (kstrtoul(buf, 10, &val))
537 return -EINVAL;
538
539 if (val > 1)
540 return -EINVAL;
541
542 pm_debug_messages_on = !!val;
543 return n;
544}
545
546power_attr(pm_debug_messages);
547
548static int __init pm_debug_messages_setup(char *str)
549{
550 pm_debug_messages_on = true;
551 return 1;
552}
553__setup("pm_debug_messages", pm_debug_messages_setup);
554
555#else /* !CONFIG_PM_SLEEP_DEBUG */
556static inline void pm_print_times_init(void) {}
557#endif /* CONFIG_PM_SLEEP_DEBUG */
558
559struct kobject *power_kobj;
560
561/*
562 * state - control system sleep states.
563 *
564 * show() returns available sleep state labels, which may be "mem", "standby",
565 * "freeze" and "disk" (hibernation).
566 * See Documentation/admin-guide/pm/sleep-states.rst for a description of
567 * what they mean.
568 *
569 * store() accepts one of those strings, translates it into the proper
570 * enumerated value, and initiates a suspend transition.
571 */
572static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
573 char *buf)
574{
575 char *s = buf;
576#ifdef CONFIG_SUSPEND
577 suspend_state_t i;
578
579 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
580 if (pm_states[i])
581 s += sprintf(s,"%s ", pm_states[i]);
582
583#endif
584 if (hibernation_available())
585 s += sprintf(s, "disk ");
586 if (s != buf)
587 /* convert the last space to a newline */
588 *(s-1) = '\n';
589 return (s - buf);
590}
591
592static suspend_state_t decode_state(const char *buf, size_t n)
593{
594#ifdef CONFIG_SUSPEND
595 suspend_state_t state;
596#endif
597 char *p;
598 int len;
599
600 p = memchr(buf, '\n', n);
601 len = p ? p - buf : n;
602
603 /* Check hibernation first. */
604 if (len == 4 && str_has_prefix(buf, "disk"))
605 return PM_SUSPEND_MAX;
606
607#ifdef CONFIG_SUSPEND
608 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
609 const char *label = pm_states[state];
610
611 if (label && len == strlen(label) && !strncmp(buf, label, len))
612 return state;
613 }
614#endif
615
616 return PM_SUSPEND_ON;
617}
618
619static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
620 const char *buf, size_t n)
621{
622 suspend_state_t state;
623 int error;
624
625 error = pm_autosleep_lock();
626 if (error)
627 return error;
628
629 if (pm_autosleep_state() > PM_SUSPEND_ON) {
630 error = -EBUSY;
631 goto out;
632 }
633
634 state = decode_state(buf, n);
635 if (state < PM_SUSPEND_MAX) {
636 if (state == PM_SUSPEND_MEM)
637 state = mem_sleep_current;
638
639 error = pm_suspend(state);
640 } else if (state == PM_SUSPEND_MAX) {
641 error = hibernate();
642 } else {
643 error = -EINVAL;
644 }
645
646 out:
647 pm_autosleep_unlock();
648 return error ? error : n;
649}
650
651power_attr(state);
652
653#ifdef CONFIG_PM_SLEEP
654/*
655 * The 'wakeup_count' attribute, along with the functions defined in
656 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
657 * handled in a non-racy way.
658 *
659 * If a wakeup event occurs when the system is in a sleep state, it simply is
660 * woken up. In turn, if an event that would wake the system up from a sleep
661 * state occurs when it is undergoing a transition to that sleep state, the
662 * transition should be aborted. Moreover, if such an event occurs when the
663 * system is in the working state, an attempt to start a transition to the
664 * given sleep state should fail during certain period after the detection of
665 * the event. Using the 'state' attribute alone is not sufficient to satisfy
666 * these requirements, because a wakeup event may occur exactly when 'state'
667 * is being written to and may be delivered to user space right before it is
668 * frozen, so the event will remain only partially processed until the system is
669 * woken up by another event. In particular, it won't cause the transition to
670 * a sleep state to be aborted.
671 *
672 * This difficulty may be overcome if user space uses 'wakeup_count' before
673 * writing to 'state'. It first should read from 'wakeup_count' and store
674 * the read value. Then, after carrying out its own preparations for the system
675 * transition to a sleep state, it should write the stored value to
676 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
677 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
678 * is allowed to write to 'state', but the transition will be aborted if there
679 * are any wakeup events detected after 'wakeup_count' was written to.
680 */
681
682static ssize_t wakeup_count_show(struct kobject *kobj,
683 struct kobj_attribute *attr,
684 char *buf)
685{
686 unsigned int val;
687
688 return pm_get_wakeup_count(&val, true) ?
689 sprintf(buf, "%u\n", val) : -EINTR;
690}
691
692static ssize_t wakeup_count_store(struct kobject *kobj,
693 struct kobj_attribute *attr,
694 const char *buf, size_t n)
695{
696 unsigned int val;
697 int error;
698
699 error = pm_autosleep_lock();
700 if (error)
701 return error;
702
703 if (pm_autosleep_state() > PM_SUSPEND_ON) {
704 error = -EBUSY;
705 goto out;
706 }
707
708 error = -EINVAL;
709 if (sscanf(buf, "%u", &val) == 1) {
710 if (pm_save_wakeup_count(val))
711 error = n;
712 else
713 pm_print_active_wakeup_sources();
714 }
715
716 out:
717 pm_autosleep_unlock();
718 return error;
719}
720
721power_attr(wakeup_count);
722
723#ifdef CONFIG_PM_AUTOSLEEP
724static ssize_t autosleep_show(struct kobject *kobj,
725 struct kobj_attribute *attr,
726 char *buf)
727{
728 suspend_state_t state = pm_autosleep_state();
729
730 if (state == PM_SUSPEND_ON)
731 return sprintf(buf, "off\n");
732
733#ifdef CONFIG_SUSPEND
734 if (state < PM_SUSPEND_MAX)
735 return sprintf(buf, "%s\n", pm_states[state] ?
736 pm_states[state] : "error");
737#endif
738#ifdef CONFIG_HIBERNATION
739 return sprintf(buf, "disk\n");
740#else
741 return sprintf(buf, "error");
742#endif
743}
744
745static ssize_t autosleep_store(struct kobject *kobj,
746 struct kobj_attribute *attr,
747 const char *buf, size_t n)
748{
749 suspend_state_t state = decode_state(buf, n);
750 int error;
751
752 if (state == PM_SUSPEND_ON
753 && strcmp(buf, "off") && strcmp(buf, "off\n"))
754 return -EINVAL;
755
756 if (state == PM_SUSPEND_MEM)
757 state = mem_sleep_current;
758
759 error = pm_autosleep_set_state(state);
760 return error ? error : n;
761}
762
763power_attr(autosleep);
764#endif /* CONFIG_PM_AUTOSLEEP */
765
766#ifdef CONFIG_PM_WAKELOCKS
767static ssize_t wake_lock_show(struct kobject *kobj,
768 struct kobj_attribute *attr,
769 char *buf)
770{
771 return pm_show_wakelocks(buf, true);
772}
773
774static ssize_t wake_lock_store(struct kobject *kobj,
775 struct kobj_attribute *attr,
776 const char *buf, size_t n)
777{
778 int error = pm_wake_lock(buf);
779 return error ? error : n;
780}
781
782power_attr(wake_lock);
783
784static ssize_t wake_unlock_show(struct kobject *kobj,
785 struct kobj_attribute *attr,
786 char *buf)
787{
788 return pm_show_wakelocks(buf, false);
789}
790
791static ssize_t wake_unlock_store(struct kobject *kobj,
792 struct kobj_attribute *attr,
793 const char *buf, size_t n)
794{
795 int error = pm_wake_unlock(buf);
796 return error ? error : n;
797}
798
799power_attr(wake_unlock);
800
801#endif /* CONFIG_PM_WAKELOCKS */
802#endif /* CONFIG_PM_SLEEP */
803
804#ifdef CONFIG_PM_TRACE
805int pm_trace_enabled;
806
807static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
808 char *buf)
809{
810 return sprintf(buf, "%d\n", pm_trace_enabled);
811}
812
813static ssize_t
814pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
815 const char *buf, size_t n)
816{
817 int val;
818
819 if (sscanf(buf, "%d", &val) == 1) {
820 pm_trace_enabled = !!val;
821 if (pm_trace_enabled) {
822 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
823 "PM: Correct system time has to be restored manually after resume.\n");
824 }
825 return n;
826 }
827 return -EINVAL;
828}
829
830power_attr(pm_trace);
831
832static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
833 struct kobj_attribute *attr,
834 char *buf)
835{
836 return show_trace_dev_match(buf, PAGE_SIZE);
837}
838
839power_attr_ro(pm_trace_dev_match);
840
841#endif /* CONFIG_PM_TRACE */
842
843#ifdef CONFIG_FREEZER
844static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
845 struct kobj_attribute *attr, char *buf)
846{
847 return sprintf(buf, "%u\n", freeze_timeout_msecs);
848}
849
850static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
851 struct kobj_attribute *attr,
852 const char *buf, size_t n)
853{
854 unsigned long val;
855
856 if (kstrtoul(buf, 10, &val))
857 return -EINVAL;
858
859 freeze_timeout_msecs = val;
860 return n;
861}
862
863power_attr(pm_freeze_timeout);
864
865#endif /* CONFIG_FREEZER*/
866
867static struct attribute * g[] = {
868 &state_attr.attr,
869#ifdef CONFIG_PM_TRACE
870 &pm_trace_attr.attr,
871 &pm_trace_dev_match_attr.attr,
872#endif
873#ifdef CONFIG_PM_SLEEP
874 &pm_async_attr.attr,
875 &wakeup_count_attr.attr,
876#ifdef CONFIG_SUSPEND
877 &mem_sleep_attr.attr,
878 &sync_on_suspend_attr.attr,
879#endif
880#ifdef CONFIG_PM_AUTOSLEEP
881 &autosleep_attr.attr,
882#endif
883#ifdef CONFIG_PM_WAKELOCKS
884 &wake_lock_attr.attr,
885 &wake_unlock_attr.attr,
886#endif
887#ifdef CONFIG_PM_SLEEP_DEBUG
888 &pm_test_attr.attr,
889 &pm_print_times_attr.attr,
890 &pm_wakeup_irq_attr.attr,
891 &pm_debug_messages_attr.attr,
892#endif
893#endif
894#ifdef CONFIG_FREEZER
895 &pm_freeze_timeout_attr.attr,
896#endif
897 NULL,
898};
899
900static const struct attribute_group attr_group = {
901 .attrs = g,
902};
903
904static const struct attribute_group *attr_groups[] = {
905 &attr_group,
906#ifdef CONFIG_PM_SLEEP
907 &suspend_attr_group,
908#endif
909 NULL,
910};
911
912struct workqueue_struct *pm_wq;
913EXPORT_SYMBOL_GPL(pm_wq);
914
915static int __init pm_start_workqueue(void)
916{
917 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
918
919 return pm_wq ? 0 : -ENOMEM;
920}
921
922static int __init pm_init(void)
923{
924 int error = pm_start_workqueue();
925 if (error)
926 return error;
927 hibernate_image_size_init();
928 hibernate_reserved_size_init();
929 pm_states_init();
930 power_kobj = kobject_create_and_add("power", NULL);
931 if (!power_kobj)
932 return -ENOMEM;
933 error = sysfs_create_groups(power_kobj, attr_groups);
934 if (error)
935 return error;
936 pm_print_times_init();
937 return pm_autosleep_init();
938}
939
940core_initcall(pm_init);
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/acpi.h>
10#include <linux/export.h>
11#include <linux/kobject.h>
12#include <linux/string.h>
13#include <linux/pm-trace.h>
14#include <linux/workqueue.h>
15#include <linux/debugfs.h>
16#include <linux/seq_file.h>
17#include <linux/suspend.h>
18#include <linux/syscalls.h>
19#include <linux/pm_runtime.h>
20
21#include "power.h"
22
23#ifdef CONFIG_PM_SLEEP
24/*
25 * The following functions are used by the suspend/hibernate code to temporarily
26 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
27 * while devices are suspended. To avoid races with the suspend/hibernate code,
28 * they should always be called with system_transition_mutex held
29 * (gfp_allowed_mask also should only be modified with system_transition_mutex
30 * held, unless the suspend/hibernate code is guaranteed not to run in parallel
31 * with that modification).
32 */
33static gfp_t saved_gfp_mask;
34
35void pm_restore_gfp_mask(void)
36{
37 WARN_ON(!mutex_is_locked(&system_transition_mutex));
38 if (saved_gfp_mask) {
39 gfp_allowed_mask = saved_gfp_mask;
40 saved_gfp_mask = 0;
41 }
42}
43
44void pm_restrict_gfp_mask(void)
45{
46 WARN_ON(!mutex_is_locked(&system_transition_mutex));
47 WARN_ON(saved_gfp_mask);
48 saved_gfp_mask = gfp_allowed_mask;
49 gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS);
50}
51
52unsigned int lock_system_sleep(void)
53{
54 unsigned int flags = current->flags;
55 current->flags |= PF_NOFREEZE;
56 mutex_lock(&system_transition_mutex);
57 return flags;
58}
59EXPORT_SYMBOL_GPL(lock_system_sleep);
60
61void unlock_system_sleep(unsigned int flags)
62{
63 if (!(flags & PF_NOFREEZE))
64 current->flags &= ~PF_NOFREEZE;
65 mutex_unlock(&system_transition_mutex);
66}
67EXPORT_SYMBOL_GPL(unlock_system_sleep);
68
69void ksys_sync_helper(void)
70{
71 ktime_t start;
72 long elapsed_msecs;
73
74 start = ktime_get();
75 ksys_sync();
76 elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start));
77 pr_info("Filesystems sync: %ld.%03ld seconds\n",
78 elapsed_msecs / MSEC_PER_SEC, elapsed_msecs % MSEC_PER_SEC);
79}
80EXPORT_SYMBOL_GPL(ksys_sync_helper);
81
82/* Routines for PM-transition notifications */
83
84static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
85
86int register_pm_notifier(struct notifier_block *nb)
87{
88 return blocking_notifier_chain_register(&pm_chain_head, nb);
89}
90EXPORT_SYMBOL_GPL(register_pm_notifier);
91
92int unregister_pm_notifier(struct notifier_block *nb)
93{
94 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
95}
96EXPORT_SYMBOL_GPL(unregister_pm_notifier);
97
98void pm_report_hw_sleep_time(u64 t)
99{
100 suspend_stats.last_hw_sleep = t;
101 suspend_stats.total_hw_sleep += t;
102}
103EXPORT_SYMBOL_GPL(pm_report_hw_sleep_time);
104
105void pm_report_max_hw_sleep(u64 t)
106{
107 suspend_stats.max_hw_sleep = t;
108}
109EXPORT_SYMBOL_GPL(pm_report_max_hw_sleep);
110
111int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down)
112{
113 int ret;
114
115 ret = blocking_notifier_call_chain_robust(&pm_chain_head, val_up, val_down, NULL);
116
117 return notifier_to_errno(ret);
118}
119
120int pm_notifier_call_chain(unsigned long val)
121{
122 return blocking_notifier_call_chain(&pm_chain_head, val, NULL);
123}
124
125/* If set, devices may be suspended and resumed asynchronously. */
126int pm_async_enabled = 1;
127
128static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
129 char *buf)
130{
131 return sprintf(buf, "%d\n", pm_async_enabled);
132}
133
134static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
135 const char *buf, size_t n)
136{
137 unsigned long val;
138
139 if (kstrtoul(buf, 10, &val))
140 return -EINVAL;
141
142 if (val > 1)
143 return -EINVAL;
144
145 pm_async_enabled = val;
146 return n;
147}
148
149power_attr(pm_async);
150
151#ifdef CONFIG_SUSPEND
152static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
153 char *buf)
154{
155 char *s = buf;
156 suspend_state_t i;
157
158 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) {
159 if (i >= PM_SUSPEND_MEM && cxl_mem_active())
160 continue;
161 if (mem_sleep_states[i]) {
162 const char *label = mem_sleep_states[i];
163
164 if (mem_sleep_current == i)
165 s += sprintf(s, "[%s] ", label);
166 else
167 s += sprintf(s, "%s ", label);
168 }
169 }
170
171 /* Convert the last space to a newline if needed. */
172 if (s != buf)
173 *(s-1) = '\n';
174
175 return (s - buf);
176}
177
178static suspend_state_t decode_suspend_state(const char *buf, size_t n)
179{
180 suspend_state_t state;
181 char *p;
182 int len;
183
184 p = memchr(buf, '\n', n);
185 len = p ? p - buf : n;
186
187 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
188 const char *label = mem_sleep_states[state];
189
190 if (label && len == strlen(label) && !strncmp(buf, label, len))
191 return state;
192 }
193
194 return PM_SUSPEND_ON;
195}
196
197static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
198 const char *buf, size_t n)
199{
200 suspend_state_t state;
201 int error;
202
203 error = pm_autosleep_lock();
204 if (error)
205 return error;
206
207 if (pm_autosleep_state() > PM_SUSPEND_ON) {
208 error = -EBUSY;
209 goto out;
210 }
211
212 state = decode_suspend_state(buf, n);
213 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
214 mem_sleep_current = state;
215 else
216 error = -EINVAL;
217
218 out:
219 pm_autosleep_unlock();
220 return error ? error : n;
221}
222
223power_attr(mem_sleep);
224
225/*
226 * sync_on_suspend: invoke ksys_sync_helper() before suspend.
227 *
228 * show() returns whether ksys_sync_helper() is invoked before suspend.
229 * store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it.
230 */
231bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC);
232
233static ssize_t sync_on_suspend_show(struct kobject *kobj,
234 struct kobj_attribute *attr, char *buf)
235{
236 return sprintf(buf, "%d\n", sync_on_suspend_enabled);
237}
238
239static ssize_t sync_on_suspend_store(struct kobject *kobj,
240 struct kobj_attribute *attr,
241 const char *buf, size_t n)
242{
243 unsigned long val;
244
245 if (kstrtoul(buf, 10, &val))
246 return -EINVAL;
247
248 if (val > 1)
249 return -EINVAL;
250
251 sync_on_suspend_enabled = !!val;
252 return n;
253}
254
255power_attr(sync_on_suspend);
256#endif /* CONFIG_SUSPEND */
257
258#ifdef CONFIG_PM_SLEEP_DEBUG
259int pm_test_level = TEST_NONE;
260
261static const char * const pm_tests[__TEST_AFTER_LAST] = {
262 [TEST_NONE] = "none",
263 [TEST_CORE] = "core",
264 [TEST_CPUS] = "processors",
265 [TEST_PLATFORM] = "platform",
266 [TEST_DEVICES] = "devices",
267 [TEST_FREEZER] = "freezer",
268};
269
270static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
271 char *buf)
272{
273 char *s = buf;
274 int level;
275
276 for (level = TEST_FIRST; level <= TEST_MAX; level++)
277 if (pm_tests[level]) {
278 if (level == pm_test_level)
279 s += sprintf(s, "[%s] ", pm_tests[level]);
280 else
281 s += sprintf(s, "%s ", pm_tests[level]);
282 }
283
284 if (s != buf)
285 /* convert the last space to a newline */
286 *(s-1) = '\n';
287
288 return (s - buf);
289}
290
291static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
292 const char *buf, size_t n)
293{
294 unsigned int sleep_flags;
295 const char * const *s;
296 int error = -EINVAL;
297 int level;
298 char *p;
299 int len;
300
301 p = memchr(buf, '\n', n);
302 len = p ? p - buf : n;
303
304 sleep_flags = lock_system_sleep();
305
306 level = TEST_FIRST;
307 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
308 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
309 pm_test_level = level;
310 error = 0;
311 break;
312 }
313
314 unlock_system_sleep(sleep_flags);
315
316 return error ? error : n;
317}
318
319power_attr(pm_test);
320#endif /* CONFIG_PM_SLEEP_DEBUG */
321
322static char *suspend_step_name(enum suspend_stat_step step)
323{
324 switch (step) {
325 case SUSPEND_FREEZE:
326 return "freeze";
327 case SUSPEND_PREPARE:
328 return "prepare";
329 case SUSPEND_SUSPEND:
330 return "suspend";
331 case SUSPEND_SUSPEND_NOIRQ:
332 return "suspend_noirq";
333 case SUSPEND_RESUME_NOIRQ:
334 return "resume_noirq";
335 case SUSPEND_RESUME:
336 return "resume";
337 default:
338 return "";
339 }
340}
341
342#define suspend_attr(_name, format_str) \
343static ssize_t _name##_show(struct kobject *kobj, \
344 struct kobj_attribute *attr, char *buf) \
345{ \
346 return sprintf(buf, format_str, suspend_stats._name); \
347} \
348static struct kobj_attribute _name = __ATTR_RO(_name)
349
350suspend_attr(success, "%d\n");
351suspend_attr(fail, "%d\n");
352suspend_attr(failed_freeze, "%d\n");
353suspend_attr(failed_prepare, "%d\n");
354suspend_attr(failed_suspend, "%d\n");
355suspend_attr(failed_suspend_late, "%d\n");
356suspend_attr(failed_suspend_noirq, "%d\n");
357suspend_attr(failed_resume, "%d\n");
358suspend_attr(failed_resume_early, "%d\n");
359suspend_attr(failed_resume_noirq, "%d\n");
360suspend_attr(last_hw_sleep, "%llu\n");
361suspend_attr(total_hw_sleep, "%llu\n");
362suspend_attr(max_hw_sleep, "%llu\n");
363
364static ssize_t last_failed_dev_show(struct kobject *kobj,
365 struct kobj_attribute *attr, char *buf)
366{
367 int index;
368 char *last_failed_dev = NULL;
369
370 index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
371 index %= REC_FAILED_NUM;
372 last_failed_dev = suspend_stats.failed_devs[index];
373
374 return sprintf(buf, "%s\n", last_failed_dev);
375}
376static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
377
378static ssize_t last_failed_errno_show(struct kobject *kobj,
379 struct kobj_attribute *attr, char *buf)
380{
381 int index;
382 int last_failed_errno;
383
384 index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
385 index %= REC_FAILED_NUM;
386 last_failed_errno = suspend_stats.errno[index];
387
388 return sprintf(buf, "%d\n", last_failed_errno);
389}
390static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
391
392static ssize_t last_failed_step_show(struct kobject *kobj,
393 struct kobj_attribute *attr, char *buf)
394{
395 int index;
396 enum suspend_stat_step step;
397 char *last_failed_step = NULL;
398
399 index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
400 index %= REC_FAILED_NUM;
401 step = suspend_stats.failed_steps[index];
402 last_failed_step = suspend_step_name(step);
403
404 return sprintf(buf, "%s\n", last_failed_step);
405}
406static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
407
408static struct attribute *suspend_attrs[] = {
409 &success.attr,
410 &fail.attr,
411 &failed_freeze.attr,
412 &failed_prepare.attr,
413 &failed_suspend.attr,
414 &failed_suspend_late.attr,
415 &failed_suspend_noirq.attr,
416 &failed_resume.attr,
417 &failed_resume_early.attr,
418 &failed_resume_noirq.attr,
419 &last_failed_dev.attr,
420 &last_failed_errno.attr,
421 &last_failed_step.attr,
422 &last_hw_sleep.attr,
423 &total_hw_sleep.attr,
424 &max_hw_sleep.attr,
425 NULL,
426};
427
428static umode_t suspend_attr_is_visible(struct kobject *kobj, struct attribute *attr, int idx)
429{
430 if (attr != &last_hw_sleep.attr &&
431 attr != &total_hw_sleep.attr &&
432 attr != &max_hw_sleep.attr)
433 return 0444;
434
435#ifdef CONFIG_ACPI
436 if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
437 return 0444;
438#endif
439 return 0;
440}
441
442static const struct attribute_group suspend_attr_group = {
443 .name = "suspend_stats",
444 .attrs = suspend_attrs,
445 .is_visible = suspend_attr_is_visible,
446};
447
448#ifdef CONFIG_DEBUG_FS
449static int suspend_stats_show(struct seq_file *s, void *unused)
450{
451 int i, index, last_dev, last_errno, last_step;
452
453 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
454 last_dev %= REC_FAILED_NUM;
455 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
456 last_errno %= REC_FAILED_NUM;
457 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
458 last_step %= REC_FAILED_NUM;
459 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
460 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
461 "success", suspend_stats.success,
462 "fail", suspend_stats.fail,
463 "failed_freeze", suspend_stats.failed_freeze,
464 "failed_prepare", suspend_stats.failed_prepare,
465 "failed_suspend", suspend_stats.failed_suspend,
466 "failed_suspend_late",
467 suspend_stats.failed_suspend_late,
468 "failed_suspend_noirq",
469 suspend_stats.failed_suspend_noirq,
470 "failed_resume", suspend_stats.failed_resume,
471 "failed_resume_early",
472 suspend_stats.failed_resume_early,
473 "failed_resume_noirq",
474 suspend_stats.failed_resume_noirq);
475 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
476 suspend_stats.failed_devs[last_dev]);
477 for (i = 1; i < REC_FAILED_NUM; i++) {
478 index = last_dev + REC_FAILED_NUM - i;
479 index %= REC_FAILED_NUM;
480 seq_printf(s, "\t\t\t%-s\n",
481 suspend_stats.failed_devs[index]);
482 }
483 seq_printf(s, " last_failed_errno:\t%-d\n",
484 suspend_stats.errno[last_errno]);
485 for (i = 1; i < REC_FAILED_NUM; i++) {
486 index = last_errno + REC_FAILED_NUM - i;
487 index %= REC_FAILED_NUM;
488 seq_printf(s, "\t\t\t%-d\n",
489 suspend_stats.errno[index]);
490 }
491 seq_printf(s, " last_failed_step:\t%-s\n",
492 suspend_step_name(
493 suspend_stats.failed_steps[last_step]));
494 for (i = 1; i < REC_FAILED_NUM; i++) {
495 index = last_step + REC_FAILED_NUM - i;
496 index %= REC_FAILED_NUM;
497 seq_printf(s, "\t\t\t%-s\n",
498 suspend_step_name(
499 suspend_stats.failed_steps[index]));
500 }
501
502 return 0;
503}
504DEFINE_SHOW_ATTRIBUTE(suspend_stats);
505
506static int __init pm_debugfs_init(void)
507{
508 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
509 NULL, NULL, &suspend_stats_fops);
510 return 0;
511}
512
513late_initcall(pm_debugfs_init);
514#endif /* CONFIG_DEBUG_FS */
515
516#endif /* CONFIG_PM_SLEEP */
517
518#ifdef CONFIG_PM_SLEEP_DEBUG
519/*
520 * pm_print_times: print time taken by devices to suspend and resume.
521 *
522 * show() returns whether printing of suspend and resume times is enabled.
523 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
524 */
525bool pm_print_times_enabled;
526
527static ssize_t pm_print_times_show(struct kobject *kobj,
528 struct kobj_attribute *attr, char *buf)
529{
530 return sprintf(buf, "%d\n", pm_print_times_enabled);
531}
532
533static ssize_t pm_print_times_store(struct kobject *kobj,
534 struct kobj_attribute *attr,
535 const char *buf, size_t n)
536{
537 unsigned long val;
538
539 if (kstrtoul(buf, 10, &val))
540 return -EINVAL;
541
542 if (val > 1)
543 return -EINVAL;
544
545 pm_print_times_enabled = !!val;
546 return n;
547}
548
549power_attr(pm_print_times);
550
551static inline void pm_print_times_init(void)
552{
553 pm_print_times_enabled = !!initcall_debug;
554}
555
556static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
557 struct kobj_attribute *attr,
558 char *buf)
559{
560 if (!pm_wakeup_irq())
561 return -ENODATA;
562
563 return sprintf(buf, "%u\n", pm_wakeup_irq());
564}
565
566power_attr_ro(pm_wakeup_irq);
567
568bool pm_debug_messages_on __read_mostly;
569
570bool pm_debug_messages_should_print(void)
571{
572 return pm_debug_messages_on && pm_suspend_target_state != PM_SUSPEND_ON;
573}
574EXPORT_SYMBOL_GPL(pm_debug_messages_should_print);
575
576static ssize_t pm_debug_messages_show(struct kobject *kobj,
577 struct kobj_attribute *attr, char *buf)
578{
579 return sprintf(buf, "%d\n", pm_debug_messages_on);
580}
581
582static ssize_t pm_debug_messages_store(struct kobject *kobj,
583 struct kobj_attribute *attr,
584 const char *buf, size_t n)
585{
586 unsigned long val;
587
588 if (kstrtoul(buf, 10, &val))
589 return -EINVAL;
590
591 if (val > 1)
592 return -EINVAL;
593
594 pm_debug_messages_on = !!val;
595 return n;
596}
597
598power_attr(pm_debug_messages);
599
600static int __init pm_debug_messages_setup(char *str)
601{
602 pm_debug_messages_on = true;
603 return 1;
604}
605__setup("pm_debug_messages", pm_debug_messages_setup);
606
607#else /* !CONFIG_PM_SLEEP_DEBUG */
608static inline void pm_print_times_init(void) {}
609#endif /* CONFIG_PM_SLEEP_DEBUG */
610
611struct kobject *power_kobj;
612
613/*
614 * state - control system sleep states.
615 *
616 * show() returns available sleep state labels, which may be "mem", "standby",
617 * "freeze" and "disk" (hibernation).
618 * See Documentation/admin-guide/pm/sleep-states.rst for a description of
619 * what they mean.
620 *
621 * store() accepts one of those strings, translates it into the proper
622 * enumerated value, and initiates a suspend transition.
623 */
624static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
625 char *buf)
626{
627 char *s = buf;
628#ifdef CONFIG_SUSPEND
629 suspend_state_t i;
630
631 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
632 if (pm_states[i])
633 s += sprintf(s,"%s ", pm_states[i]);
634
635#endif
636 if (hibernation_available())
637 s += sprintf(s, "disk ");
638 if (s != buf)
639 /* convert the last space to a newline */
640 *(s-1) = '\n';
641 return (s - buf);
642}
643
644static suspend_state_t decode_state(const char *buf, size_t n)
645{
646#ifdef CONFIG_SUSPEND
647 suspend_state_t state;
648#endif
649 char *p;
650 int len;
651
652 p = memchr(buf, '\n', n);
653 len = p ? p - buf : n;
654
655 /* Check hibernation first. */
656 if (len == 4 && str_has_prefix(buf, "disk"))
657 return PM_SUSPEND_MAX;
658
659#ifdef CONFIG_SUSPEND
660 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
661 const char *label = pm_states[state];
662
663 if (label && len == strlen(label) && !strncmp(buf, label, len))
664 return state;
665 }
666#endif
667
668 return PM_SUSPEND_ON;
669}
670
671static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
672 const char *buf, size_t n)
673{
674 suspend_state_t state;
675 int error;
676
677 error = pm_autosleep_lock();
678 if (error)
679 return error;
680
681 if (pm_autosleep_state() > PM_SUSPEND_ON) {
682 error = -EBUSY;
683 goto out;
684 }
685
686 state = decode_state(buf, n);
687 if (state < PM_SUSPEND_MAX) {
688 if (state == PM_SUSPEND_MEM)
689 state = mem_sleep_current;
690
691 error = pm_suspend(state);
692 } else if (state == PM_SUSPEND_MAX) {
693 error = hibernate();
694 } else {
695 error = -EINVAL;
696 }
697
698 out:
699 pm_autosleep_unlock();
700 return error ? error : n;
701}
702
703power_attr(state);
704
705#ifdef CONFIG_PM_SLEEP
706/*
707 * The 'wakeup_count' attribute, along with the functions defined in
708 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
709 * handled in a non-racy way.
710 *
711 * If a wakeup event occurs when the system is in a sleep state, it simply is
712 * woken up. In turn, if an event that would wake the system up from a sleep
713 * state occurs when it is undergoing a transition to that sleep state, the
714 * transition should be aborted. Moreover, if such an event occurs when the
715 * system is in the working state, an attempt to start a transition to the
716 * given sleep state should fail during certain period after the detection of
717 * the event. Using the 'state' attribute alone is not sufficient to satisfy
718 * these requirements, because a wakeup event may occur exactly when 'state'
719 * is being written to and may be delivered to user space right before it is
720 * frozen, so the event will remain only partially processed until the system is
721 * woken up by another event. In particular, it won't cause the transition to
722 * a sleep state to be aborted.
723 *
724 * This difficulty may be overcome if user space uses 'wakeup_count' before
725 * writing to 'state'. It first should read from 'wakeup_count' and store
726 * the read value. Then, after carrying out its own preparations for the system
727 * transition to a sleep state, it should write the stored value to
728 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
729 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
730 * is allowed to write to 'state', but the transition will be aborted if there
731 * are any wakeup events detected after 'wakeup_count' was written to.
732 */
733
734static ssize_t wakeup_count_show(struct kobject *kobj,
735 struct kobj_attribute *attr,
736 char *buf)
737{
738 unsigned int val;
739
740 return pm_get_wakeup_count(&val, true) ?
741 sprintf(buf, "%u\n", val) : -EINTR;
742}
743
744static ssize_t wakeup_count_store(struct kobject *kobj,
745 struct kobj_attribute *attr,
746 const char *buf, size_t n)
747{
748 unsigned int val;
749 int error;
750
751 error = pm_autosleep_lock();
752 if (error)
753 return error;
754
755 if (pm_autosleep_state() > PM_SUSPEND_ON) {
756 error = -EBUSY;
757 goto out;
758 }
759
760 error = -EINVAL;
761 if (sscanf(buf, "%u", &val) == 1) {
762 if (pm_save_wakeup_count(val))
763 error = n;
764 else
765 pm_print_active_wakeup_sources();
766 }
767
768 out:
769 pm_autosleep_unlock();
770 return error;
771}
772
773power_attr(wakeup_count);
774
775#ifdef CONFIG_PM_AUTOSLEEP
776static ssize_t autosleep_show(struct kobject *kobj,
777 struct kobj_attribute *attr,
778 char *buf)
779{
780 suspend_state_t state = pm_autosleep_state();
781
782 if (state == PM_SUSPEND_ON)
783 return sprintf(buf, "off\n");
784
785#ifdef CONFIG_SUSPEND
786 if (state < PM_SUSPEND_MAX)
787 return sprintf(buf, "%s\n", pm_states[state] ?
788 pm_states[state] : "error");
789#endif
790#ifdef CONFIG_HIBERNATION
791 return sprintf(buf, "disk\n");
792#else
793 return sprintf(buf, "error");
794#endif
795}
796
797static ssize_t autosleep_store(struct kobject *kobj,
798 struct kobj_attribute *attr,
799 const char *buf, size_t n)
800{
801 suspend_state_t state = decode_state(buf, n);
802 int error;
803
804 if (state == PM_SUSPEND_ON
805 && strcmp(buf, "off") && strcmp(buf, "off\n"))
806 return -EINVAL;
807
808 if (state == PM_SUSPEND_MEM)
809 state = mem_sleep_current;
810
811 error = pm_autosleep_set_state(state);
812 return error ? error : n;
813}
814
815power_attr(autosleep);
816#endif /* CONFIG_PM_AUTOSLEEP */
817
818#ifdef CONFIG_PM_WAKELOCKS
819static ssize_t wake_lock_show(struct kobject *kobj,
820 struct kobj_attribute *attr,
821 char *buf)
822{
823 return pm_show_wakelocks(buf, true);
824}
825
826static ssize_t wake_lock_store(struct kobject *kobj,
827 struct kobj_attribute *attr,
828 const char *buf, size_t n)
829{
830 int error = pm_wake_lock(buf);
831 return error ? error : n;
832}
833
834power_attr(wake_lock);
835
836static ssize_t wake_unlock_show(struct kobject *kobj,
837 struct kobj_attribute *attr,
838 char *buf)
839{
840 return pm_show_wakelocks(buf, false);
841}
842
843static ssize_t wake_unlock_store(struct kobject *kobj,
844 struct kobj_attribute *attr,
845 const char *buf, size_t n)
846{
847 int error = pm_wake_unlock(buf);
848 return error ? error : n;
849}
850
851power_attr(wake_unlock);
852
853#endif /* CONFIG_PM_WAKELOCKS */
854#endif /* CONFIG_PM_SLEEP */
855
856#ifdef CONFIG_PM_TRACE
857int pm_trace_enabled;
858
859static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
860 char *buf)
861{
862 return sprintf(buf, "%d\n", pm_trace_enabled);
863}
864
865static ssize_t
866pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
867 const char *buf, size_t n)
868{
869 int val;
870
871 if (sscanf(buf, "%d", &val) == 1) {
872 pm_trace_enabled = !!val;
873 if (pm_trace_enabled) {
874 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
875 "PM: Correct system time has to be restored manually after resume.\n");
876 }
877 return n;
878 }
879 return -EINVAL;
880}
881
882power_attr(pm_trace);
883
884static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
885 struct kobj_attribute *attr,
886 char *buf)
887{
888 return show_trace_dev_match(buf, PAGE_SIZE);
889}
890
891power_attr_ro(pm_trace_dev_match);
892
893#endif /* CONFIG_PM_TRACE */
894
895#ifdef CONFIG_FREEZER
896static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
897 struct kobj_attribute *attr, char *buf)
898{
899 return sprintf(buf, "%u\n", freeze_timeout_msecs);
900}
901
902static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
903 struct kobj_attribute *attr,
904 const char *buf, size_t n)
905{
906 unsigned long val;
907
908 if (kstrtoul(buf, 10, &val))
909 return -EINVAL;
910
911 freeze_timeout_msecs = val;
912 return n;
913}
914
915power_attr(pm_freeze_timeout);
916
917#endif /* CONFIG_FREEZER*/
918
919static struct attribute * g[] = {
920 &state_attr.attr,
921#ifdef CONFIG_PM_TRACE
922 &pm_trace_attr.attr,
923 &pm_trace_dev_match_attr.attr,
924#endif
925#ifdef CONFIG_PM_SLEEP
926 &pm_async_attr.attr,
927 &wakeup_count_attr.attr,
928#ifdef CONFIG_SUSPEND
929 &mem_sleep_attr.attr,
930 &sync_on_suspend_attr.attr,
931#endif
932#ifdef CONFIG_PM_AUTOSLEEP
933 &autosleep_attr.attr,
934#endif
935#ifdef CONFIG_PM_WAKELOCKS
936 &wake_lock_attr.attr,
937 &wake_unlock_attr.attr,
938#endif
939#ifdef CONFIG_PM_SLEEP_DEBUG
940 &pm_test_attr.attr,
941 &pm_print_times_attr.attr,
942 &pm_wakeup_irq_attr.attr,
943 &pm_debug_messages_attr.attr,
944#endif
945#endif
946#ifdef CONFIG_FREEZER
947 &pm_freeze_timeout_attr.attr,
948#endif
949 NULL,
950};
951
952static const struct attribute_group attr_group = {
953 .attrs = g,
954};
955
956static const struct attribute_group *attr_groups[] = {
957 &attr_group,
958#ifdef CONFIG_PM_SLEEP
959 &suspend_attr_group,
960#endif
961 NULL,
962};
963
964struct workqueue_struct *pm_wq;
965EXPORT_SYMBOL_GPL(pm_wq);
966
967static int __init pm_start_workqueue(void)
968{
969 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
970
971 return pm_wq ? 0 : -ENOMEM;
972}
973
974static int __init pm_init(void)
975{
976 int error = pm_start_workqueue();
977 if (error)
978 return error;
979 hibernate_image_size_init();
980 hibernate_reserved_size_init();
981 pm_states_init();
982 power_kobj = kobject_create_and_add("power", NULL);
983 if (!power_kobj)
984 return -ENOMEM;
985 error = sysfs_create_groups(power_kobj, attr_groups);
986 if (error)
987 return error;
988 pm_print_times_init();
989 return pm_autosleep_init();
990}
991
992core_initcall(pm_init);