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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
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
98int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down)
99{
100 int ret;
101
102 ret = blocking_notifier_call_chain_robust(&pm_chain_head, val_up, val_down, NULL);
103
104 return notifier_to_errno(ret);
105}
106
107int pm_notifier_call_chain(unsigned long val)
108{
109 return blocking_notifier_call_chain(&pm_chain_head, val, NULL);
110}
111
112/* If set, devices may be suspended and resumed asynchronously. */
113int pm_async_enabled = 1;
114
115static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
116 char *buf)
117{
118 return sysfs_emit(buf, "%d\n", pm_async_enabled);
119}
120
121static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
122 const char *buf, size_t n)
123{
124 unsigned long val;
125
126 if (kstrtoul(buf, 10, &val))
127 return -EINVAL;
128
129 if (val > 1)
130 return -EINVAL;
131
132 pm_async_enabled = val;
133 return n;
134}
135
136power_attr(pm_async);
137
138#ifdef CONFIG_SUSPEND
139static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
140 char *buf)
141{
142 ssize_t count = 0;
143 suspend_state_t i;
144
145 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++) {
146 if (i >= PM_SUSPEND_MEM && cxl_mem_active())
147 continue;
148 if (mem_sleep_states[i]) {
149 const char *label = mem_sleep_states[i];
150
151 if (mem_sleep_current == i)
152 count += sysfs_emit_at(buf, count, "[%s] ", label);
153 else
154 count += sysfs_emit_at(buf, count, "%s ", label);
155 }
156 }
157
158 /* Convert the last space to a newline if needed. */
159 if (count > 0)
160 buf[count - 1] = '\n';
161
162 return count;
163}
164
165static suspend_state_t decode_suspend_state(const char *buf, size_t n)
166{
167 suspend_state_t state;
168 char *p;
169 int len;
170
171 p = memchr(buf, '\n', n);
172 len = p ? p - buf : n;
173
174 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
175 const char *label = mem_sleep_states[state];
176
177 if (label && len == strlen(label) && !strncmp(buf, label, len))
178 return state;
179 }
180
181 return PM_SUSPEND_ON;
182}
183
184static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
185 const char *buf, size_t n)
186{
187 suspend_state_t state;
188 int error;
189
190 error = pm_autosleep_lock();
191 if (error)
192 return error;
193
194 if (pm_autosleep_state() > PM_SUSPEND_ON) {
195 error = -EBUSY;
196 goto out;
197 }
198
199 state = decode_suspend_state(buf, n);
200 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
201 mem_sleep_current = state;
202 else
203 error = -EINVAL;
204
205 out:
206 pm_autosleep_unlock();
207 return error ? error : n;
208}
209
210power_attr(mem_sleep);
211
212/*
213 * sync_on_suspend: invoke ksys_sync_helper() before suspend.
214 *
215 * show() returns whether ksys_sync_helper() is invoked before suspend.
216 * store() accepts 0 or 1. 0 disables ksys_sync_helper() and 1 enables it.
217 */
218bool sync_on_suspend_enabled = !IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC);
219
220static ssize_t sync_on_suspend_show(struct kobject *kobj,
221 struct kobj_attribute *attr, char *buf)
222{
223 return sysfs_emit(buf, "%d\n", sync_on_suspend_enabled);
224}
225
226static ssize_t sync_on_suspend_store(struct kobject *kobj,
227 struct kobj_attribute *attr,
228 const char *buf, size_t n)
229{
230 unsigned long val;
231
232 if (kstrtoul(buf, 10, &val))
233 return -EINVAL;
234
235 if (val > 1)
236 return -EINVAL;
237
238 sync_on_suspend_enabled = !!val;
239 return n;
240}
241
242power_attr(sync_on_suspend);
243#endif /* CONFIG_SUSPEND */
244
245#ifdef CONFIG_PM_SLEEP_DEBUG
246int pm_test_level = TEST_NONE;
247
248static const char * const pm_tests[__TEST_AFTER_LAST] = {
249 [TEST_NONE] = "none",
250 [TEST_CORE] = "core",
251 [TEST_CPUS] = "processors",
252 [TEST_PLATFORM] = "platform",
253 [TEST_DEVICES] = "devices",
254 [TEST_FREEZER] = "freezer",
255};
256
257static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
258 char *buf)
259{
260 ssize_t count = 0;
261 int level;
262
263 for (level = TEST_FIRST; level <= TEST_MAX; level++)
264 if (pm_tests[level]) {
265 if (level == pm_test_level)
266 count += sysfs_emit_at(buf, count, "[%s] ", pm_tests[level]);
267 else
268 count += sysfs_emit_at(buf, count, "%s ", pm_tests[level]);
269 }
270
271 /* Convert the last space to a newline if needed. */
272 if (count > 0)
273 buf[count - 1] = '\n';
274
275 return count;
276}
277
278static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
279 const char *buf, size_t n)
280{
281 unsigned int sleep_flags;
282 const char * const *s;
283 int error = -EINVAL;
284 int level;
285 char *p;
286 int len;
287
288 p = memchr(buf, '\n', n);
289 len = p ? p - buf : n;
290
291 sleep_flags = lock_system_sleep();
292
293 level = TEST_FIRST;
294 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
295 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
296 pm_test_level = level;
297 error = 0;
298 break;
299 }
300
301 unlock_system_sleep(sleep_flags);
302
303 return error ? error : n;
304}
305
306power_attr(pm_test);
307#endif /* CONFIG_PM_SLEEP_DEBUG */
308
309#define SUSPEND_NR_STEPS SUSPEND_RESUME
310#define REC_FAILED_NUM 2
311
312struct suspend_stats {
313 unsigned int step_failures[SUSPEND_NR_STEPS];
314 unsigned int success;
315 unsigned int fail;
316 int last_failed_dev;
317 char failed_devs[REC_FAILED_NUM][40];
318 int last_failed_errno;
319 int errno[REC_FAILED_NUM];
320 int last_failed_step;
321 u64 last_hw_sleep;
322 u64 total_hw_sleep;
323 u64 max_hw_sleep;
324 enum suspend_stat_step failed_steps[REC_FAILED_NUM];
325};
326
327static struct suspend_stats suspend_stats;
328static DEFINE_MUTEX(suspend_stats_lock);
329
330void dpm_save_failed_dev(const char *name)
331{
332 mutex_lock(&suspend_stats_lock);
333
334 strscpy(suspend_stats.failed_devs[suspend_stats.last_failed_dev],
335 name, sizeof(suspend_stats.failed_devs[0]));
336 suspend_stats.last_failed_dev++;
337 suspend_stats.last_failed_dev %= REC_FAILED_NUM;
338
339 mutex_unlock(&suspend_stats_lock);
340}
341
342void dpm_save_failed_step(enum suspend_stat_step step)
343{
344 suspend_stats.step_failures[step-1]++;
345 suspend_stats.failed_steps[suspend_stats.last_failed_step] = step;
346 suspend_stats.last_failed_step++;
347 suspend_stats.last_failed_step %= REC_FAILED_NUM;
348}
349
350void dpm_save_errno(int err)
351{
352 if (!err) {
353 suspend_stats.success++;
354 return;
355 }
356
357 suspend_stats.fail++;
358
359 suspend_stats.errno[suspend_stats.last_failed_errno] = err;
360 suspend_stats.last_failed_errno++;
361 suspend_stats.last_failed_errno %= REC_FAILED_NUM;
362}
363
364void pm_report_hw_sleep_time(u64 t)
365{
366 suspend_stats.last_hw_sleep = t;
367 suspend_stats.total_hw_sleep += t;
368}
369EXPORT_SYMBOL_GPL(pm_report_hw_sleep_time);
370
371void pm_report_max_hw_sleep(u64 t)
372{
373 suspend_stats.max_hw_sleep = t;
374}
375EXPORT_SYMBOL_GPL(pm_report_max_hw_sleep);
376
377static const char * const suspend_step_names[] = {
378 [SUSPEND_WORKING] = "",
379 [SUSPEND_FREEZE] = "freeze",
380 [SUSPEND_PREPARE] = "prepare",
381 [SUSPEND_SUSPEND] = "suspend",
382 [SUSPEND_SUSPEND_LATE] = "suspend_late",
383 [SUSPEND_SUSPEND_NOIRQ] = "suspend_noirq",
384 [SUSPEND_RESUME_NOIRQ] = "resume_noirq",
385 [SUSPEND_RESUME_EARLY] = "resume_early",
386 [SUSPEND_RESUME] = "resume",
387};
388
389#define suspend_attr(_name, format_str) \
390static ssize_t _name##_show(struct kobject *kobj, \
391 struct kobj_attribute *attr, char *buf) \
392{ \
393 return sysfs_emit(buf, format_str, suspend_stats._name);\
394} \
395static struct kobj_attribute _name = __ATTR_RO(_name)
396
397suspend_attr(success, "%u\n");
398suspend_attr(fail, "%u\n");
399suspend_attr(last_hw_sleep, "%llu\n");
400suspend_attr(total_hw_sleep, "%llu\n");
401suspend_attr(max_hw_sleep, "%llu\n");
402
403#define suspend_step_attr(_name, step) \
404static ssize_t _name##_show(struct kobject *kobj, \
405 struct kobj_attribute *attr, char *buf) \
406{ \
407 return sysfs_emit(buf, "%u\n", \
408 suspend_stats.step_failures[step-1]); \
409} \
410static struct kobj_attribute _name = __ATTR_RO(_name)
411
412suspend_step_attr(failed_freeze, SUSPEND_FREEZE);
413suspend_step_attr(failed_prepare, SUSPEND_PREPARE);
414suspend_step_attr(failed_suspend, SUSPEND_SUSPEND);
415suspend_step_attr(failed_suspend_late, SUSPEND_SUSPEND_LATE);
416suspend_step_attr(failed_suspend_noirq, SUSPEND_SUSPEND_NOIRQ);
417suspend_step_attr(failed_resume, SUSPEND_RESUME);
418suspend_step_attr(failed_resume_early, SUSPEND_RESUME_EARLY);
419suspend_step_attr(failed_resume_noirq, SUSPEND_RESUME_NOIRQ);
420
421static ssize_t last_failed_dev_show(struct kobject *kobj,
422 struct kobj_attribute *attr, char *buf)
423{
424 int index;
425 char *last_failed_dev = NULL;
426
427 index = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
428 index %= REC_FAILED_NUM;
429 last_failed_dev = suspend_stats.failed_devs[index];
430
431 return sysfs_emit(buf, "%s\n", last_failed_dev);
432}
433static struct kobj_attribute last_failed_dev = __ATTR_RO(last_failed_dev);
434
435static ssize_t last_failed_errno_show(struct kobject *kobj,
436 struct kobj_attribute *attr, char *buf)
437{
438 int index;
439 int last_failed_errno;
440
441 index = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
442 index %= REC_FAILED_NUM;
443 last_failed_errno = suspend_stats.errno[index];
444
445 return sysfs_emit(buf, "%d\n", last_failed_errno);
446}
447static struct kobj_attribute last_failed_errno = __ATTR_RO(last_failed_errno);
448
449static ssize_t last_failed_step_show(struct kobject *kobj,
450 struct kobj_attribute *attr, char *buf)
451{
452 enum suspend_stat_step step;
453 int index;
454
455 index = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
456 index %= REC_FAILED_NUM;
457 step = suspend_stats.failed_steps[index];
458
459 return sysfs_emit(buf, "%s\n", suspend_step_names[step]);
460}
461static struct kobj_attribute last_failed_step = __ATTR_RO(last_failed_step);
462
463static struct attribute *suspend_attrs[] = {
464 &success.attr,
465 &fail.attr,
466 &failed_freeze.attr,
467 &failed_prepare.attr,
468 &failed_suspend.attr,
469 &failed_suspend_late.attr,
470 &failed_suspend_noirq.attr,
471 &failed_resume.attr,
472 &failed_resume_early.attr,
473 &failed_resume_noirq.attr,
474 &last_failed_dev.attr,
475 &last_failed_errno.attr,
476 &last_failed_step.attr,
477 &last_hw_sleep.attr,
478 &total_hw_sleep.attr,
479 &max_hw_sleep.attr,
480 NULL,
481};
482
483static umode_t suspend_attr_is_visible(struct kobject *kobj, struct attribute *attr, int idx)
484{
485 if (attr != &last_hw_sleep.attr &&
486 attr != &total_hw_sleep.attr &&
487 attr != &max_hw_sleep.attr)
488 return 0444;
489
490#ifdef CONFIG_ACPI
491 if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
492 return 0444;
493#endif
494 return 0;
495}
496
497static const struct attribute_group suspend_attr_group = {
498 .name = "suspend_stats",
499 .attrs = suspend_attrs,
500 .is_visible = suspend_attr_is_visible,
501};
502
503#ifdef CONFIG_DEBUG_FS
504static int suspend_stats_show(struct seq_file *s, void *unused)
505{
506 int i, index, last_dev, last_errno, last_step;
507 enum suspend_stat_step step;
508
509 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
510 last_dev %= REC_FAILED_NUM;
511 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
512 last_errno %= REC_FAILED_NUM;
513 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
514 last_step %= REC_FAILED_NUM;
515
516 seq_printf(s, "success: %u\nfail: %u\n",
517 suspend_stats.success, suspend_stats.fail);
518
519 for (step = SUSPEND_FREEZE; step <= SUSPEND_NR_STEPS; step++)
520 seq_printf(s, "failed_%s: %u\n", suspend_step_names[step],
521 suspend_stats.step_failures[step-1]);
522
523 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
524 suspend_stats.failed_devs[last_dev]);
525 for (i = 1; i < REC_FAILED_NUM; i++) {
526 index = last_dev + REC_FAILED_NUM - i;
527 index %= REC_FAILED_NUM;
528 seq_printf(s, "\t\t\t%-s\n", suspend_stats.failed_devs[index]);
529 }
530 seq_printf(s, " last_failed_errno:\t%-d\n",
531 suspend_stats.errno[last_errno]);
532 for (i = 1; i < REC_FAILED_NUM; i++) {
533 index = last_errno + REC_FAILED_NUM - i;
534 index %= REC_FAILED_NUM;
535 seq_printf(s, "\t\t\t%-d\n", suspend_stats.errno[index]);
536 }
537 seq_printf(s, " last_failed_step:\t%-s\n",
538 suspend_step_names[suspend_stats.failed_steps[last_step]]);
539 for (i = 1; i < REC_FAILED_NUM; i++) {
540 index = last_step + REC_FAILED_NUM - i;
541 index %= REC_FAILED_NUM;
542 seq_printf(s, "\t\t\t%-s\n",
543 suspend_step_names[suspend_stats.failed_steps[index]]);
544 }
545
546 return 0;
547}
548DEFINE_SHOW_ATTRIBUTE(suspend_stats);
549
550static int __init pm_debugfs_init(void)
551{
552 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
553 NULL, NULL, &suspend_stats_fops);
554 return 0;
555}
556
557late_initcall(pm_debugfs_init);
558#endif /* CONFIG_DEBUG_FS */
559
560#endif /* CONFIG_PM_SLEEP */
561
562#ifdef CONFIG_PM_SLEEP_DEBUG
563/*
564 * pm_print_times: print time taken by devices to suspend and resume.
565 *
566 * show() returns whether printing of suspend and resume times is enabled.
567 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
568 */
569bool pm_print_times_enabled;
570
571static ssize_t pm_print_times_show(struct kobject *kobj,
572 struct kobj_attribute *attr, char *buf)
573{
574 return sysfs_emit(buf, "%d\n", pm_print_times_enabled);
575}
576
577static ssize_t pm_print_times_store(struct kobject *kobj,
578 struct kobj_attribute *attr,
579 const char *buf, size_t n)
580{
581 unsigned long val;
582
583 if (kstrtoul(buf, 10, &val))
584 return -EINVAL;
585
586 if (val > 1)
587 return -EINVAL;
588
589 pm_print_times_enabled = !!val;
590 return n;
591}
592
593power_attr(pm_print_times);
594
595static inline void pm_print_times_init(void)
596{
597 pm_print_times_enabled = !!initcall_debug;
598}
599
600static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
601 struct kobj_attribute *attr,
602 char *buf)
603{
604 if (!pm_wakeup_irq())
605 return -ENODATA;
606
607 return sysfs_emit(buf, "%u\n", pm_wakeup_irq());
608}
609
610power_attr_ro(pm_wakeup_irq);
611
612bool pm_debug_messages_on __read_mostly;
613
614bool pm_debug_messages_should_print(void)
615{
616 return pm_debug_messages_on && pm_suspend_target_state != PM_SUSPEND_ON;
617}
618EXPORT_SYMBOL_GPL(pm_debug_messages_should_print);
619
620static ssize_t pm_debug_messages_show(struct kobject *kobj,
621 struct kobj_attribute *attr, char *buf)
622{
623 return sysfs_emit(buf, "%d\n", pm_debug_messages_on);
624}
625
626static ssize_t pm_debug_messages_store(struct kobject *kobj,
627 struct kobj_attribute *attr,
628 const char *buf, size_t n)
629{
630 unsigned long val;
631
632 if (kstrtoul(buf, 10, &val))
633 return -EINVAL;
634
635 if (val > 1)
636 return -EINVAL;
637
638 pm_debug_messages_on = !!val;
639 return n;
640}
641
642power_attr(pm_debug_messages);
643
644static int __init pm_debug_messages_setup(char *str)
645{
646 pm_debug_messages_on = true;
647 return 1;
648}
649__setup("pm_debug_messages", pm_debug_messages_setup);
650
651#else /* !CONFIG_PM_SLEEP_DEBUG */
652static inline void pm_print_times_init(void) {}
653#endif /* CONFIG_PM_SLEEP_DEBUG */
654
655struct kobject *power_kobj;
656
657/*
658 * state - control system sleep states.
659 *
660 * show() returns available sleep state labels, which may be "mem", "standby",
661 * "freeze" and "disk" (hibernation).
662 * See Documentation/admin-guide/pm/sleep-states.rst for a description of
663 * what they mean.
664 *
665 * store() accepts one of those strings, translates it into the proper
666 * enumerated value, and initiates a suspend transition.
667 */
668static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
669 char *buf)
670{
671 ssize_t count = 0;
672#ifdef CONFIG_SUSPEND
673 suspend_state_t i;
674
675 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
676 if (pm_states[i])
677 count += sysfs_emit_at(buf, count, "%s ", pm_states[i]);
678
679#endif
680 if (hibernation_available())
681 count += sysfs_emit_at(buf, count, "disk ");
682
683 /* Convert the last space to a newline if needed. */
684 if (count > 0)
685 buf[count - 1] = '\n';
686
687 return count;
688}
689
690static suspend_state_t decode_state(const char *buf, size_t n)
691{
692#ifdef CONFIG_SUSPEND
693 suspend_state_t state;
694#endif
695 char *p;
696 int len;
697
698 p = memchr(buf, '\n', n);
699 len = p ? p - buf : n;
700
701 /* Check hibernation first. */
702 if (len == 4 && str_has_prefix(buf, "disk"))
703 return PM_SUSPEND_MAX;
704
705#ifdef CONFIG_SUSPEND
706 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
707 const char *label = pm_states[state];
708
709 if (label && len == strlen(label) && !strncmp(buf, label, len))
710 return state;
711 }
712#endif
713
714 return PM_SUSPEND_ON;
715}
716
717static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
718 const char *buf, size_t n)
719{
720 suspend_state_t state;
721 int error;
722
723 error = pm_autosleep_lock();
724 if (error)
725 return error;
726
727 if (pm_autosleep_state() > PM_SUSPEND_ON) {
728 error = -EBUSY;
729 goto out;
730 }
731
732 state = decode_state(buf, n);
733 if (state < PM_SUSPEND_MAX) {
734 if (state == PM_SUSPEND_MEM)
735 state = mem_sleep_current;
736
737 error = pm_suspend(state);
738 } else if (state == PM_SUSPEND_MAX) {
739 error = hibernate();
740 } else {
741 error = -EINVAL;
742 }
743
744 out:
745 pm_autosleep_unlock();
746 return error ? error : n;
747}
748
749power_attr(state);
750
751#ifdef CONFIG_PM_SLEEP
752/*
753 * The 'wakeup_count' attribute, along with the functions defined in
754 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
755 * handled in a non-racy way.
756 *
757 * If a wakeup event occurs when the system is in a sleep state, it simply is
758 * woken up. In turn, if an event that would wake the system up from a sleep
759 * state occurs when it is undergoing a transition to that sleep state, the
760 * transition should be aborted. Moreover, if such an event occurs when the
761 * system is in the working state, an attempt to start a transition to the
762 * given sleep state should fail during certain period after the detection of
763 * the event. Using the 'state' attribute alone is not sufficient to satisfy
764 * these requirements, because a wakeup event may occur exactly when 'state'
765 * is being written to and may be delivered to user space right before it is
766 * frozen, so the event will remain only partially processed until the system is
767 * woken up by another event. In particular, it won't cause the transition to
768 * a sleep state to be aborted.
769 *
770 * This difficulty may be overcome if user space uses 'wakeup_count' before
771 * writing to 'state'. It first should read from 'wakeup_count' and store
772 * the read value. Then, after carrying out its own preparations for the system
773 * transition to a sleep state, it should write the stored value to
774 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
775 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
776 * is allowed to write to 'state', but the transition will be aborted if there
777 * are any wakeup events detected after 'wakeup_count' was written to.
778 */
779
780static ssize_t wakeup_count_show(struct kobject *kobj,
781 struct kobj_attribute *attr,
782 char *buf)
783{
784 unsigned int val;
785
786 return pm_get_wakeup_count(&val, true) ?
787 sysfs_emit(buf, "%u\n", val) : -EINTR;
788}
789
790static ssize_t wakeup_count_store(struct kobject *kobj,
791 struct kobj_attribute *attr,
792 const char *buf, size_t n)
793{
794 unsigned int val;
795 int error;
796
797 error = pm_autosleep_lock();
798 if (error)
799 return error;
800
801 if (pm_autosleep_state() > PM_SUSPEND_ON) {
802 error = -EBUSY;
803 goto out;
804 }
805
806 error = -EINVAL;
807 if (sscanf(buf, "%u", &val) == 1) {
808 if (pm_save_wakeup_count(val))
809 error = n;
810 else
811 pm_print_active_wakeup_sources();
812 }
813
814 out:
815 pm_autosleep_unlock();
816 return error;
817}
818
819power_attr(wakeup_count);
820
821#ifdef CONFIG_PM_AUTOSLEEP
822static ssize_t autosleep_show(struct kobject *kobj,
823 struct kobj_attribute *attr,
824 char *buf)
825{
826 suspend_state_t state = pm_autosleep_state();
827
828 if (state == PM_SUSPEND_ON)
829 return sysfs_emit(buf, "off\n");
830
831#ifdef CONFIG_SUSPEND
832 if (state < PM_SUSPEND_MAX)
833 return sysfs_emit(buf, "%s\n", pm_states[state] ?
834 pm_states[state] : "error");
835#endif
836#ifdef CONFIG_HIBERNATION
837 return sysfs_emit(buf, "disk\n");
838#else
839 return sysfs_emit(buf, "error\n");
840#endif
841}
842
843static ssize_t autosleep_store(struct kobject *kobj,
844 struct kobj_attribute *attr,
845 const char *buf, size_t n)
846{
847 suspend_state_t state = decode_state(buf, n);
848 int error;
849
850 if (state == PM_SUSPEND_ON
851 && strcmp(buf, "off") && strcmp(buf, "off\n"))
852 return -EINVAL;
853
854 if (state == PM_SUSPEND_MEM)
855 state = mem_sleep_current;
856
857 error = pm_autosleep_set_state(state);
858 return error ? error : n;
859}
860
861power_attr(autosleep);
862#endif /* CONFIG_PM_AUTOSLEEP */
863
864#ifdef CONFIG_PM_WAKELOCKS
865static ssize_t wake_lock_show(struct kobject *kobj,
866 struct kobj_attribute *attr,
867 char *buf)
868{
869 return pm_show_wakelocks(buf, true);
870}
871
872static ssize_t wake_lock_store(struct kobject *kobj,
873 struct kobj_attribute *attr,
874 const char *buf, size_t n)
875{
876 int error = pm_wake_lock(buf);
877 return error ? error : n;
878}
879
880power_attr(wake_lock);
881
882static ssize_t wake_unlock_show(struct kobject *kobj,
883 struct kobj_attribute *attr,
884 char *buf)
885{
886 return pm_show_wakelocks(buf, false);
887}
888
889static ssize_t wake_unlock_store(struct kobject *kobj,
890 struct kobj_attribute *attr,
891 const char *buf, size_t n)
892{
893 int error = pm_wake_unlock(buf);
894 return error ? error : n;
895}
896
897power_attr(wake_unlock);
898
899#endif /* CONFIG_PM_WAKELOCKS */
900#endif /* CONFIG_PM_SLEEP */
901
902#ifdef CONFIG_PM_TRACE
903int pm_trace_enabled;
904
905static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
906 char *buf)
907{
908 return sysfs_emit(buf, "%d\n", pm_trace_enabled);
909}
910
911static ssize_t
912pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
913 const char *buf, size_t n)
914{
915 int val;
916
917 if (sscanf(buf, "%d", &val) == 1) {
918 pm_trace_enabled = !!val;
919 if (pm_trace_enabled) {
920 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
921 "PM: Correct system time has to be restored manually after resume.\n");
922 }
923 return n;
924 }
925 return -EINVAL;
926}
927
928power_attr(pm_trace);
929
930static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
931 struct kobj_attribute *attr,
932 char *buf)
933{
934 return show_trace_dev_match(buf, PAGE_SIZE);
935}
936
937power_attr_ro(pm_trace_dev_match);
938
939#endif /* CONFIG_PM_TRACE */
940
941#ifdef CONFIG_FREEZER
942static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
943 struct kobj_attribute *attr, char *buf)
944{
945 return sysfs_emit(buf, "%u\n", freeze_timeout_msecs);
946}
947
948static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
949 struct kobj_attribute *attr,
950 const char *buf, size_t n)
951{
952 unsigned long val;
953
954 if (kstrtoul(buf, 10, &val))
955 return -EINVAL;
956
957 freeze_timeout_msecs = val;
958 return n;
959}
960
961power_attr(pm_freeze_timeout);
962
963#endif /* CONFIG_FREEZER*/
964
965static struct attribute * g[] = {
966 &state_attr.attr,
967#ifdef CONFIG_PM_TRACE
968 &pm_trace_attr.attr,
969 &pm_trace_dev_match_attr.attr,
970#endif
971#ifdef CONFIG_PM_SLEEP
972 &pm_async_attr.attr,
973 &wakeup_count_attr.attr,
974#ifdef CONFIG_SUSPEND
975 &mem_sleep_attr.attr,
976 &sync_on_suspend_attr.attr,
977#endif
978#ifdef CONFIG_PM_AUTOSLEEP
979 &autosleep_attr.attr,
980#endif
981#ifdef CONFIG_PM_WAKELOCKS
982 &wake_lock_attr.attr,
983 &wake_unlock_attr.attr,
984#endif
985#ifdef CONFIG_PM_SLEEP_DEBUG
986 &pm_test_attr.attr,
987 &pm_print_times_attr.attr,
988 &pm_wakeup_irq_attr.attr,
989 &pm_debug_messages_attr.attr,
990#endif
991#endif
992#ifdef CONFIG_FREEZER
993 &pm_freeze_timeout_attr.attr,
994#endif
995 NULL,
996};
997
998static const struct attribute_group attr_group = {
999 .attrs = g,
1000};
1001
1002static const struct attribute_group *attr_groups[] = {
1003 &attr_group,
1004#ifdef CONFIG_PM_SLEEP
1005 &suspend_attr_group,
1006#endif
1007 NULL,
1008};
1009
1010struct workqueue_struct *pm_wq;
1011EXPORT_SYMBOL_GPL(pm_wq);
1012
1013static int __init pm_start_workqueue(void)
1014{
1015 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
1016
1017 return pm_wq ? 0 : -ENOMEM;
1018}
1019
1020static int __init pm_init(void)
1021{
1022 int error = pm_start_workqueue();
1023 if (error)
1024 return error;
1025 hibernate_image_size_init();
1026 hibernate_reserved_size_init();
1027 pm_states_init();
1028 power_kobj = kobject_create_and_add("power", NULL);
1029 if (!power_kobj)
1030 return -ENOMEM;
1031 error = sysfs_create_groups(power_kobj, attr_groups);
1032 if (error)
1033 return error;
1034 pm_print_times_init();
1035 return pm_autosleep_init();
1036}
1037
1038core_initcall(pm_init);