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1/*
2 * kernel/power/main.c - PM subsystem core functionality.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 *
7 * This file is released under the GPLv2
8 *
9 */
10
11#include <linux/export.h>
12#include <linux/kobject.h>
13#include <linux/string.h>
14#include <linux/pm-trace.h>
15#include <linux/workqueue.h>
16#include <linux/debugfs.h>
17#include <linux/seq_file.h>
18
19#include "power.h"
20
21DEFINE_MUTEX(pm_mutex);
22
23#ifdef CONFIG_PM_SLEEP
24
25/* Routines for PM-transition notifications */
26
27static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
28
29int register_pm_notifier(struct notifier_block *nb)
30{
31 return blocking_notifier_chain_register(&pm_chain_head, nb);
32}
33EXPORT_SYMBOL_GPL(register_pm_notifier);
34
35int unregister_pm_notifier(struct notifier_block *nb)
36{
37 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
38}
39EXPORT_SYMBOL_GPL(unregister_pm_notifier);
40
41int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
42{
43 int ret;
44
45 ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
46 nr_to_call, nr_calls);
47
48 return notifier_to_errno(ret);
49}
50int pm_notifier_call_chain(unsigned long val)
51{
52 return __pm_notifier_call_chain(val, -1, NULL);
53}
54
55/* If set, devices may be suspended and resumed asynchronously. */
56int pm_async_enabled = 1;
57
58static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
59 char *buf)
60{
61 return sprintf(buf, "%d\n", pm_async_enabled);
62}
63
64static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
65 const char *buf, size_t n)
66{
67 unsigned long val;
68
69 if (kstrtoul(buf, 10, &val))
70 return -EINVAL;
71
72 if (val > 1)
73 return -EINVAL;
74
75 pm_async_enabled = val;
76 return n;
77}
78
79power_attr(pm_async);
80
81#ifdef CONFIG_SUSPEND
82static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
83 char *buf)
84{
85 char *s = buf;
86 suspend_state_t i;
87
88 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
89 if (mem_sleep_states[i]) {
90 const char *label = mem_sleep_states[i];
91
92 if (mem_sleep_current == i)
93 s += sprintf(s, "[%s] ", label);
94 else
95 s += sprintf(s, "%s ", label);
96 }
97
98 /* Convert the last space to a newline if needed. */
99 if (s != buf)
100 *(s-1) = '\n';
101
102 return (s - buf);
103}
104
105static suspend_state_t decode_suspend_state(const char *buf, size_t n)
106{
107 suspend_state_t state;
108 char *p;
109 int len;
110
111 p = memchr(buf, '\n', n);
112 len = p ? p - buf : n;
113
114 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
115 const char *label = mem_sleep_states[state];
116
117 if (label && len == strlen(label) && !strncmp(buf, label, len))
118 return state;
119 }
120
121 return PM_SUSPEND_ON;
122}
123
124static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
125 const char *buf, size_t n)
126{
127 suspend_state_t state;
128 int error;
129
130 error = pm_autosleep_lock();
131 if (error)
132 return error;
133
134 if (pm_autosleep_state() > PM_SUSPEND_ON) {
135 error = -EBUSY;
136 goto out;
137 }
138
139 state = decode_suspend_state(buf, n);
140 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
141 mem_sleep_current = state;
142 else
143 error = -EINVAL;
144
145 out:
146 pm_autosleep_unlock();
147 return error ? error : n;
148}
149
150power_attr(mem_sleep);
151#endif /* CONFIG_SUSPEND */
152
153#ifdef CONFIG_PM_DEBUG
154int pm_test_level = TEST_NONE;
155
156static const char * const pm_tests[__TEST_AFTER_LAST] = {
157 [TEST_NONE] = "none",
158 [TEST_CORE] = "core",
159 [TEST_CPUS] = "processors",
160 [TEST_PLATFORM] = "platform",
161 [TEST_DEVICES] = "devices",
162 [TEST_FREEZER] = "freezer",
163};
164
165static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
166 char *buf)
167{
168 char *s = buf;
169 int level;
170
171 for (level = TEST_FIRST; level <= TEST_MAX; level++)
172 if (pm_tests[level]) {
173 if (level == pm_test_level)
174 s += sprintf(s, "[%s] ", pm_tests[level]);
175 else
176 s += sprintf(s, "%s ", pm_tests[level]);
177 }
178
179 if (s != buf)
180 /* convert the last space to a newline */
181 *(s-1) = '\n';
182
183 return (s - buf);
184}
185
186static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
187 const char *buf, size_t n)
188{
189 const char * const *s;
190 int level;
191 char *p;
192 int len;
193 int error = -EINVAL;
194
195 p = memchr(buf, '\n', n);
196 len = p ? p - buf : n;
197
198 lock_system_sleep();
199
200 level = TEST_FIRST;
201 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
202 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
203 pm_test_level = level;
204 error = 0;
205 break;
206 }
207
208 unlock_system_sleep();
209
210 return error ? error : n;
211}
212
213power_attr(pm_test);
214#endif /* CONFIG_PM_DEBUG */
215
216#ifdef CONFIG_DEBUG_FS
217static char *suspend_step_name(enum suspend_stat_step step)
218{
219 switch (step) {
220 case SUSPEND_FREEZE:
221 return "freeze";
222 case SUSPEND_PREPARE:
223 return "prepare";
224 case SUSPEND_SUSPEND:
225 return "suspend";
226 case SUSPEND_SUSPEND_NOIRQ:
227 return "suspend_noirq";
228 case SUSPEND_RESUME_NOIRQ:
229 return "resume_noirq";
230 case SUSPEND_RESUME:
231 return "resume";
232 default:
233 return "";
234 }
235}
236
237static int suspend_stats_show(struct seq_file *s, void *unused)
238{
239 int i, index, last_dev, last_errno, last_step;
240
241 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
242 last_dev %= REC_FAILED_NUM;
243 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
244 last_errno %= REC_FAILED_NUM;
245 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
246 last_step %= REC_FAILED_NUM;
247 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
248 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
249 "success", suspend_stats.success,
250 "fail", suspend_stats.fail,
251 "failed_freeze", suspend_stats.failed_freeze,
252 "failed_prepare", suspend_stats.failed_prepare,
253 "failed_suspend", suspend_stats.failed_suspend,
254 "failed_suspend_late",
255 suspend_stats.failed_suspend_late,
256 "failed_suspend_noirq",
257 suspend_stats.failed_suspend_noirq,
258 "failed_resume", suspend_stats.failed_resume,
259 "failed_resume_early",
260 suspend_stats.failed_resume_early,
261 "failed_resume_noirq",
262 suspend_stats.failed_resume_noirq);
263 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
264 suspend_stats.failed_devs[last_dev]);
265 for (i = 1; i < REC_FAILED_NUM; i++) {
266 index = last_dev + REC_FAILED_NUM - i;
267 index %= REC_FAILED_NUM;
268 seq_printf(s, "\t\t\t%-s\n",
269 suspend_stats.failed_devs[index]);
270 }
271 seq_printf(s, " last_failed_errno:\t%-d\n",
272 suspend_stats.errno[last_errno]);
273 for (i = 1; i < REC_FAILED_NUM; i++) {
274 index = last_errno + REC_FAILED_NUM - i;
275 index %= REC_FAILED_NUM;
276 seq_printf(s, "\t\t\t%-d\n",
277 suspend_stats.errno[index]);
278 }
279 seq_printf(s, " last_failed_step:\t%-s\n",
280 suspend_step_name(
281 suspend_stats.failed_steps[last_step]));
282 for (i = 1; i < REC_FAILED_NUM; i++) {
283 index = last_step + REC_FAILED_NUM - i;
284 index %= REC_FAILED_NUM;
285 seq_printf(s, "\t\t\t%-s\n",
286 suspend_step_name(
287 suspend_stats.failed_steps[index]));
288 }
289
290 return 0;
291}
292
293static int suspend_stats_open(struct inode *inode, struct file *file)
294{
295 return single_open(file, suspend_stats_show, NULL);
296}
297
298static const struct file_operations suspend_stats_operations = {
299 .open = suspend_stats_open,
300 .read = seq_read,
301 .llseek = seq_lseek,
302 .release = single_release,
303};
304
305static int __init pm_debugfs_init(void)
306{
307 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
308 NULL, NULL, &suspend_stats_operations);
309 return 0;
310}
311
312late_initcall(pm_debugfs_init);
313#endif /* CONFIG_DEBUG_FS */
314
315#endif /* CONFIG_PM_SLEEP */
316
317#ifdef CONFIG_PM_SLEEP_DEBUG
318/*
319 * pm_print_times: print time taken by devices to suspend and resume.
320 *
321 * show() returns whether printing of suspend and resume times is enabled.
322 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
323 */
324bool pm_print_times_enabled;
325
326static ssize_t pm_print_times_show(struct kobject *kobj,
327 struct kobj_attribute *attr, char *buf)
328{
329 return sprintf(buf, "%d\n", pm_print_times_enabled);
330}
331
332static ssize_t pm_print_times_store(struct kobject *kobj,
333 struct kobj_attribute *attr,
334 const char *buf, size_t n)
335{
336 unsigned long val;
337
338 if (kstrtoul(buf, 10, &val))
339 return -EINVAL;
340
341 if (val > 1)
342 return -EINVAL;
343
344 pm_print_times_enabled = !!val;
345 return n;
346}
347
348power_attr(pm_print_times);
349
350static inline void pm_print_times_init(void)
351{
352 pm_print_times_enabled = !!initcall_debug;
353}
354
355static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
356 struct kobj_attribute *attr,
357 char *buf)
358{
359 return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA;
360}
361
362power_attr_ro(pm_wakeup_irq);
363
364#else /* !CONFIG_PM_SLEEP_DEBUG */
365static inline void pm_print_times_init(void) {}
366#endif /* CONFIG_PM_SLEEP_DEBUG */
367
368struct kobject *power_kobj;
369
370/**
371 * state - control system sleep states.
372 *
373 * show() returns available sleep state labels, which may be "mem", "standby",
374 * "freeze" and "disk" (hibernation). See Documentation/power/states.txt for a
375 * description of what they mean.
376 *
377 * store() accepts one of those strings, translates it into the proper
378 * enumerated value, and initiates a suspend transition.
379 */
380static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
381 char *buf)
382{
383 char *s = buf;
384#ifdef CONFIG_SUSPEND
385 suspend_state_t i;
386
387 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
388 if (pm_states[i])
389 s += sprintf(s,"%s ", pm_states[i]);
390
391#endif
392 if (hibernation_available())
393 s += sprintf(s, "disk ");
394 if (s != buf)
395 /* convert the last space to a newline */
396 *(s-1) = '\n';
397 return (s - buf);
398}
399
400static suspend_state_t decode_state(const char *buf, size_t n)
401{
402#ifdef CONFIG_SUSPEND
403 suspend_state_t state;
404#endif
405 char *p;
406 int len;
407
408 p = memchr(buf, '\n', n);
409 len = p ? p - buf : n;
410
411 /* Check hibernation first. */
412 if (len == 4 && !strncmp(buf, "disk", len))
413 return PM_SUSPEND_MAX;
414
415#ifdef CONFIG_SUSPEND
416 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
417 const char *label = pm_states[state];
418
419 if (label && len == strlen(label) && !strncmp(buf, label, len))
420 return state;
421 }
422#endif
423
424 return PM_SUSPEND_ON;
425}
426
427static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
428 const char *buf, size_t n)
429{
430 suspend_state_t state;
431 int error;
432
433 error = pm_autosleep_lock();
434 if (error)
435 return error;
436
437 if (pm_autosleep_state() > PM_SUSPEND_ON) {
438 error = -EBUSY;
439 goto out;
440 }
441
442 state = decode_state(buf, n);
443 if (state < PM_SUSPEND_MAX) {
444 if (state == PM_SUSPEND_MEM)
445 state = mem_sleep_current;
446
447 error = pm_suspend(state);
448 } else if (state == PM_SUSPEND_MAX) {
449 error = hibernate();
450 } else {
451 error = -EINVAL;
452 }
453
454 out:
455 pm_autosleep_unlock();
456 return error ? error : n;
457}
458
459power_attr(state);
460
461#ifdef CONFIG_PM_SLEEP
462/*
463 * The 'wakeup_count' attribute, along with the functions defined in
464 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
465 * handled in a non-racy way.
466 *
467 * If a wakeup event occurs when the system is in a sleep state, it simply is
468 * woken up. In turn, if an event that would wake the system up from a sleep
469 * state occurs when it is undergoing a transition to that sleep state, the
470 * transition should be aborted. Moreover, if such an event occurs when the
471 * system is in the working state, an attempt to start a transition to the
472 * given sleep state should fail during certain period after the detection of
473 * the event. Using the 'state' attribute alone is not sufficient to satisfy
474 * these requirements, because a wakeup event may occur exactly when 'state'
475 * is being written to and may be delivered to user space right before it is
476 * frozen, so the event will remain only partially processed until the system is
477 * woken up by another event. In particular, it won't cause the transition to
478 * a sleep state to be aborted.
479 *
480 * This difficulty may be overcome if user space uses 'wakeup_count' before
481 * writing to 'state'. It first should read from 'wakeup_count' and store
482 * the read value. Then, after carrying out its own preparations for the system
483 * transition to a sleep state, it should write the stored value to
484 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
485 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
486 * is allowed to write to 'state', but the transition will be aborted if there
487 * are any wakeup events detected after 'wakeup_count' was written to.
488 */
489
490static ssize_t wakeup_count_show(struct kobject *kobj,
491 struct kobj_attribute *attr,
492 char *buf)
493{
494 unsigned int val;
495
496 return pm_get_wakeup_count(&val, true) ?
497 sprintf(buf, "%u\n", val) : -EINTR;
498}
499
500static ssize_t wakeup_count_store(struct kobject *kobj,
501 struct kobj_attribute *attr,
502 const char *buf, size_t n)
503{
504 unsigned int val;
505 int error;
506
507 error = pm_autosleep_lock();
508 if (error)
509 return error;
510
511 if (pm_autosleep_state() > PM_SUSPEND_ON) {
512 error = -EBUSY;
513 goto out;
514 }
515
516 error = -EINVAL;
517 if (sscanf(buf, "%u", &val) == 1) {
518 if (pm_save_wakeup_count(val))
519 error = n;
520 else
521 pm_print_active_wakeup_sources();
522 }
523
524 out:
525 pm_autosleep_unlock();
526 return error;
527}
528
529power_attr(wakeup_count);
530
531#ifdef CONFIG_PM_AUTOSLEEP
532static ssize_t autosleep_show(struct kobject *kobj,
533 struct kobj_attribute *attr,
534 char *buf)
535{
536 suspend_state_t state = pm_autosleep_state();
537
538 if (state == PM_SUSPEND_ON)
539 return sprintf(buf, "off\n");
540
541#ifdef CONFIG_SUSPEND
542 if (state < PM_SUSPEND_MAX)
543 return sprintf(buf, "%s\n", pm_states[state] ?
544 pm_states[state] : "error");
545#endif
546#ifdef CONFIG_HIBERNATION
547 return sprintf(buf, "disk\n");
548#else
549 return sprintf(buf, "error");
550#endif
551}
552
553static ssize_t autosleep_store(struct kobject *kobj,
554 struct kobj_attribute *attr,
555 const char *buf, size_t n)
556{
557 suspend_state_t state = decode_state(buf, n);
558 int error;
559
560 if (state == PM_SUSPEND_ON
561 && strcmp(buf, "off") && strcmp(buf, "off\n"))
562 return -EINVAL;
563
564 if (state == PM_SUSPEND_MEM)
565 state = mem_sleep_current;
566
567 error = pm_autosleep_set_state(state);
568 return error ? error : n;
569}
570
571power_attr(autosleep);
572#endif /* CONFIG_PM_AUTOSLEEP */
573
574#ifdef CONFIG_PM_WAKELOCKS
575static ssize_t wake_lock_show(struct kobject *kobj,
576 struct kobj_attribute *attr,
577 char *buf)
578{
579 return pm_show_wakelocks(buf, true);
580}
581
582static ssize_t wake_lock_store(struct kobject *kobj,
583 struct kobj_attribute *attr,
584 const char *buf, size_t n)
585{
586 int error = pm_wake_lock(buf);
587 return error ? error : n;
588}
589
590power_attr(wake_lock);
591
592static ssize_t wake_unlock_show(struct kobject *kobj,
593 struct kobj_attribute *attr,
594 char *buf)
595{
596 return pm_show_wakelocks(buf, false);
597}
598
599static ssize_t wake_unlock_store(struct kobject *kobj,
600 struct kobj_attribute *attr,
601 const char *buf, size_t n)
602{
603 int error = pm_wake_unlock(buf);
604 return error ? error : n;
605}
606
607power_attr(wake_unlock);
608
609#endif /* CONFIG_PM_WAKELOCKS */
610#endif /* CONFIG_PM_SLEEP */
611
612#ifdef CONFIG_PM_TRACE
613int pm_trace_enabled;
614
615static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
616 char *buf)
617{
618 return sprintf(buf, "%d\n", pm_trace_enabled);
619}
620
621static ssize_t
622pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
623 const char *buf, size_t n)
624{
625 int val;
626
627 if (sscanf(buf, "%d", &val) == 1) {
628 pm_trace_enabled = !!val;
629 if (pm_trace_enabled) {
630 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
631 "PM: Correct system time has to be restored manually after resume.\n");
632 }
633 return n;
634 }
635 return -EINVAL;
636}
637
638power_attr(pm_trace);
639
640static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
641 struct kobj_attribute *attr,
642 char *buf)
643{
644 return show_trace_dev_match(buf, PAGE_SIZE);
645}
646
647power_attr_ro(pm_trace_dev_match);
648
649#endif /* CONFIG_PM_TRACE */
650
651#ifdef CONFIG_FREEZER
652static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
653 struct kobj_attribute *attr, char *buf)
654{
655 return sprintf(buf, "%u\n", freeze_timeout_msecs);
656}
657
658static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
659 struct kobj_attribute *attr,
660 const char *buf, size_t n)
661{
662 unsigned long val;
663
664 if (kstrtoul(buf, 10, &val))
665 return -EINVAL;
666
667 freeze_timeout_msecs = val;
668 return n;
669}
670
671power_attr(pm_freeze_timeout);
672
673#endif /* CONFIG_FREEZER*/
674
675static struct attribute * g[] = {
676 &state_attr.attr,
677#ifdef CONFIG_PM_TRACE
678 &pm_trace_attr.attr,
679 &pm_trace_dev_match_attr.attr,
680#endif
681#ifdef CONFIG_PM_SLEEP
682 &pm_async_attr.attr,
683 &wakeup_count_attr.attr,
684#ifdef CONFIG_SUSPEND
685 &mem_sleep_attr.attr,
686#endif
687#ifdef CONFIG_PM_AUTOSLEEP
688 &autosleep_attr.attr,
689#endif
690#ifdef CONFIG_PM_WAKELOCKS
691 &wake_lock_attr.attr,
692 &wake_unlock_attr.attr,
693#endif
694#ifdef CONFIG_PM_DEBUG
695 &pm_test_attr.attr,
696#endif
697#ifdef CONFIG_PM_SLEEP_DEBUG
698 &pm_print_times_attr.attr,
699 &pm_wakeup_irq_attr.attr,
700#endif
701#endif
702#ifdef CONFIG_FREEZER
703 &pm_freeze_timeout_attr.attr,
704#endif
705 NULL,
706};
707
708static struct attribute_group attr_group = {
709 .attrs = g,
710};
711
712struct workqueue_struct *pm_wq;
713EXPORT_SYMBOL_GPL(pm_wq);
714
715static int __init pm_start_workqueue(void)
716{
717 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
718
719 return pm_wq ? 0 : -ENOMEM;
720}
721
722static int __init pm_init(void)
723{
724 int error = pm_start_workqueue();
725 if (error)
726 return error;
727 hibernate_image_size_init();
728 hibernate_reserved_size_init();
729 pm_states_init();
730 power_kobj = kobject_create_and_add("power", NULL);
731 if (!power_kobj)
732 return -ENOMEM;
733 error = sysfs_create_group(power_kobj, &attr_group);
734 if (error)
735 return error;
736 pm_print_times_init();
737 return pm_autosleep_init();
738}
739
740core_initcall(pm_init);
1/*
2 * kernel/power/main.c - PM subsystem core functionality.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 *
7 * This file is released under the GPLv2
8 *
9 */
10
11#include <linux/export.h>
12#include <linux/kobject.h>
13#include <linux/string.h>
14#include <linux/pm-trace.h>
15#include <linux/workqueue.h>
16#include <linux/debugfs.h>
17#include <linux/seq_file.h>
18
19#include "power.h"
20
21DEFINE_MUTEX(pm_mutex);
22
23#ifdef CONFIG_PM_SLEEP
24
25/* Routines for PM-transition notifications */
26
27static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
28
29int register_pm_notifier(struct notifier_block *nb)
30{
31 return blocking_notifier_chain_register(&pm_chain_head, nb);
32}
33EXPORT_SYMBOL_GPL(register_pm_notifier);
34
35int unregister_pm_notifier(struct notifier_block *nb)
36{
37 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
38}
39EXPORT_SYMBOL_GPL(unregister_pm_notifier);
40
41int pm_notifier_call_chain(unsigned long val)
42{
43 int ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL);
44
45 return notifier_to_errno(ret);
46}
47
48/* If set, devices may be suspended and resumed asynchronously. */
49int pm_async_enabled = 1;
50
51static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
52 char *buf)
53{
54 return sprintf(buf, "%d\n", pm_async_enabled);
55}
56
57static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
58 const char *buf, size_t n)
59{
60 unsigned long val;
61
62 if (kstrtoul(buf, 10, &val))
63 return -EINVAL;
64
65 if (val > 1)
66 return -EINVAL;
67
68 pm_async_enabled = val;
69 return n;
70}
71
72power_attr(pm_async);
73
74#ifdef CONFIG_PM_DEBUG
75int pm_test_level = TEST_NONE;
76
77static const char * const pm_tests[__TEST_AFTER_LAST] = {
78 [TEST_NONE] = "none",
79 [TEST_CORE] = "core",
80 [TEST_CPUS] = "processors",
81 [TEST_PLATFORM] = "platform",
82 [TEST_DEVICES] = "devices",
83 [TEST_FREEZER] = "freezer",
84};
85
86static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
87 char *buf)
88{
89 char *s = buf;
90 int level;
91
92 for (level = TEST_FIRST; level <= TEST_MAX; level++)
93 if (pm_tests[level]) {
94 if (level == pm_test_level)
95 s += sprintf(s, "[%s] ", pm_tests[level]);
96 else
97 s += sprintf(s, "%s ", pm_tests[level]);
98 }
99
100 if (s != buf)
101 /* convert the last space to a newline */
102 *(s-1) = '\n';
103
104 return (s - buf);
105}
106
107static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
108 const char *buf, size_t n)
109{
110 const char * const *s;
111 int level;
112 char *p;
113 int len;
114 int error = -EINVAL;
115
116 p = memchr(buf, '\n', n);
117 len = p ? p - buf : n;
118
119 lock_system_sleep();
120
121 level = TEST_FIRST;
122 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
123 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
124 pm_test_level = level;
125 error = 0;
126 break;
127 }
128
129 unlock_system_sleep();
130
131 return error ? error : n;
132}
133
134power_attr(pm_test);
135#endif /* CONFIG_PM_DEBUG */
136
137#ifdef CONFIG_DEBUG_FS
138static char *suspend_step_name(enum suspend_stat_step step)
139{
140 switch (step) {
141 case SUSPEND_FREEZE:
142 return "freeze";
143 case SUSPEND_PREPARE:
144 return "prepare";
145 case SUSPEND_SUSPEND:
146 return "suspend";
147 case SUSPEND_SUSPEND_NOIRQ:
148 return "suspend_noirq";
149 case SUSPEND_RESUME_NOIRQ:
150 return "resume_noirq";
151 case SUSPEND_RESUME:
152 return "resume";
153 default:
154 return "";
155 }
156}
157
158static int suspend_stats_show(struct seq_file *s, void *unused)
159{
160 int i, index, last_dev, last_errno, last_step;
161
162 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
163 last_dev %= REC_FAILED_NUM;
164 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
165 last_errno %= REC_FAILED_NUM;
166 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
167 last_step %= REC_FAILED_NUM;
168 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
169 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
170 "success", suspend_stats.success,
171 "fail", suspend_stats.fail,
172 "failed_freeze", suspend_stats.failed_freeze,
173 "failed_prepare", suspend_stats.failed_prepare,
174 "failed_suspend", suspend_stats.failed_suspend,
175 "failed_suspend_late",
176 suspend_stats.failed_suspend_late,
177 "failed_suspend_noirq",
178 suspend_stats.failed_suspend_noirq,
179 "failed_resume", suspend_stats.failed_resume,
180 "failed_resume_early",
181 suspend_stats.failed_resume_early,
182 "failed_resume_noirq",
183 suspend_stats.failed_resume_noirq);
184 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
185 suspend_stats.failed_devs[last_dev]);
186 for (i = 1; i < REC_FAILED_NUM; i++) {
187 index = last_dev + REC_FAILED_NUM - i;
188 index %= REC_FAILED_NUM;
189 seq_printf(s, "\t\t\t%-s\n",
190 suspend_stats.failed_devs[index]);
191 }
192 seq_printf(s, " last_failed_errno:\t%-d\n",
193 suspend_stats.errno[last_errno]);
194 for (i = 1; i < REC_FAILED_NUM; i++) {
195 index = last_errno + REC_FAILED_NUM - i;
196 index %= REC_FAILED_NUM;
197 seq_printf(s, "\t\t\t%-d\n",
198 suspend_stats.errno[index]);
199 }
200 seq_printf(s, " last_failed_step:\t%-s\n",
201 suspend_step_name(
202 suspend_stats.failed_steps[last_step]));
203 for (i = 1; i < REC_FAILED_NUM; i++) {
204 index = last_step + REC_FAILED_NUM - i;
205 index %= REC_FAILED_NUM;
206 seq_printf(s, "\t\t\t%-s\n",
207 suspend_step_name(
208 suspend_stats.failed_steps[index]));
209 }
210
211 return 0;
212}
213
214static int suspend_stats_open(struct inode *inode, struct file *file)
215{
216 return single_open(file, suspend_stats_show, NULL);
217}
218
219static const struct file_operations suspend_stats_operations = {
220 .open = suspend_stats_open,
221 .read = seq_read,
222 .llseek = seq_lseek,
223 .release = single_release,
224};
225
226static int __init pm_debugfs_init(void)
227{
228 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
229 NULL, NULL, &suspend_stats_operations);
230 return 0;
231}
232
233late_initcall(pm_debugfs_init);
234#endif /* CONFIG_DEBUG_FS */
235
236#endif /* CONFIG_PM_SLEEP */
237
238#ifdef CONFIG_PM_SLEEP_DEBUG
239/*
240 * pm_print_times: print time taken by devices to suspend and resume.
241 *
242 * show() returns whether printing of suspend and resume times is enabled.
243 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
244 */
245bool pm_print_times_enabled;
246
247static ssize_t pm_print_times_show(struct kobject *kobj,
248 struct kobj_attribute *attr, char *buf)
249{
250 return sprintf(buf, "%d\n", pm_print_times_enabled);
251}
252
253static ssize_t pm_print_times_store(struct kobject *kobj,
254 struct kobj_attribute *attr,
255 const char *buf, size_t n)
256{
257 unsigned long val;
258
259 if (kstrtoul(buf, 10, &val))
260 return -EINVAL;
261
262 if (val > 1)
263 return -EINVAL;
264
265 pm_print_times_enabled = !!val;
266 return n;
267}
268
269power_attr(pm_print_times);
270
271static inline void pm_print_times_init(void)
272{
273 pm_print_times_enabled = !!initcall_debug;
274}
275
276static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
277 struct kobj_attribute *attr,
278 char *buf)
279{
280 return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA;
281}
282
283power_attr_ro(pm_wakeup_irq);
284
285#else /* !CONFIG_PM_SLEEP_DEBUG */
286static inline void pm_print_times_init(void) {}
287#endif /* CONFIG_PM_SLEEP_DEBUG */
288
289struct kobject *power_kobj;
290
291/**
292 * state - control system sleep states.
293 *
294 * show() returns available sleep state labels, which may be "mem", "standby",
295 * "freeze" and "disk" (hibernation). See Documentation/power/states.txt for a
296 * description of what they mean.
297 *
298 * store() accepts one of those strings, translates it into the proper
299 * enumerated value, and initiates a suspend transition.
300 */
301static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
302 char *buf)
303{
304 char *s = buf;
305#ifdef CONFIG_SUSPEND
306 suspend_state_t i;
307
308 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
309 if (pm_states[i])
310 s += sprintf(s,"%s ", pm_states[i]);
311
312#endif
313 if (hibernation_available())
314 s += sprintf(s, "disk ");
315 if (s != buf)
316 /* convert the last space to a newline */
317 *(s-1) = '\n';
318 return (s - buf);
319}
320
321static suspend_state_t decode_state(const char *buf, size_t n)
322{
323#ifdef CONFIG_SUSPEND
324 suspend_state_t state;
325#endif
326 char *p;
327 int len;
328
329 p = memchr(buf, '\n', n);
330 len = p ? p - buf : n;
331
332 /* Check hibernation first. */
333 if (len == 4 && !strncmp(buf, "disk", len))
334 return PM_SUSPEND_MAX;
335
336#ifdef CONFIG_SUSPEND
337 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
338 const char *label = pm_states[state];
339
340 if (label && len == strlen(label) && !strncmp(buf, label, len))
341 return state;
342 }
343#endif
344
345 return PM_SUSPEND_ON;
346}
347
348static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
349 const char *buf, size_t n)
350{
351 suspend_state_t state;
352 int error;
353
354 error = pm_autosleep_lock();
355 if (error)
356 return error;
357
358 if (pm_autosleep_state() > PM_SUSPEND_ON) {
359 error = -EBUSY;
360 goto out;
361 }
362
363 state = decode_state(buf, n);
364 if (state < PM_SUSPEND_MAX)
365 error = pm_suspend(state);
366 else if (state == PM_SUSPEND_MAX)
367 error = hibernate();
368 else
369 error = -EINVAL;
370
371 out:
372 pm_autosleep_unlock();
373 return error ? error : n;
374}
375
376power_attr(state);
377
378#ifdef CONFIG_PM_SLEEP
379/*
380 * The 'wakeup_count' attribute, along with the functions defined in
381 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
382 * handled in a non-racy way.
383 *
384 * If a wakeup event occurs when the system is in a sleep state, it simply is
385 * woken up. In turn, if an event that would wake the system up from a sleep
386 * state occurs when it is undergoing a transition to that sleep state, the
387 * transition should be aborted. Moreover, if such an event occurs when the
388 * system is in the working state, an attempt to start a transition to the
389 * given sleep state should fail during certain period after the detection of
390 * the event. Using the 'state' attribute alone is not sufficient to satisfy
391 * these requirements, because a wakeup event may occur exactly when 'state'
392 * is being written to and may be delivered to user space right before it is
393 * frozen, so the event will remain only partially processed until the system is
394 * woken up by another event. In particular, it won't cause the transition to
395 * a sleep state to be aborted.
396 *
397 * This difficulty may be overcome if user space uses 'wakeup_count' before
398 * writing to 'state'. It first should read from 'wakeup_count' and store
399 * the read value. Then, after carrying out its own preparations for the system
400 * transition to a sleep state, it should write the stored value to
401 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
402 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
403 * is allowed to write to 'state', but the transition will be aborted if there
404 * are any wakeup events detected after 'wakeup_count' was written to.
405 */
406
407static ssize_t wakeup_count_show(struct kobject *kobj,
408 struct kobj_attribute *attr,
409 char *buf)
410{
411 unsigned int val;
412
413 return pm_get_wakeup_count(&val, true) ?
414 sprintf(buf, "%u\n", val) : -EINTR;
415}
416
417static ssize_t wakeup_count_store(struct kobject *kobj,
418 struct kobj_attribute *attr,
419 const char *buf, size_t n)
420{
421 unsigned int val;
422 int error;
423
424 error = pm_autosleep_lock();
425 if (error)
426 return error;
427
428 if (pm_autosleep_state() > PM_SUSPEND_ON) {
429 error = -EBUSY;
430 goto out;
431 }
432
433 error = -EINVAL;
434 if (sscanf(buf, "%u", &val) == 1) {
435 if (pm_save_wakeup_count(val))
436 error = n;
437 else
438 pm_print_active_wakeup_sources();
439 }
440
441 out:
442 pm_autosleep_unlock();
443 return error;
444}
445
446power_attr(wakeup_count);
447
448#ifdef CONFIG_PM_AUTOSLEEP
449static ssize_t autosleep_show(struct kobject *kobj,
450 struct kobj_attribute *attr,
451 char *buf)
452{
453 suspend_state_t state = pm_autosleep_state();
454
455 if (state == PM_SUSPEND_ON)
456 return sprintf(buf, "off\n");
457
458#ifdef CONFIG_SUSPEND
459 if (state < PM_SUSPEND_MAX)
460 return sprintf(buf, "%s\n", pm_states[state] ?
461 pm_states[state] : "error");
462#endif
463#ifdef CONFIG_HIBERNATION
464 return sprintf(buf, "disk\n");
465#else
466 return sprintf(buf, "error");
467#endif
468}
469
470static ssize_t autosleep_store(struct kobject *kobj,
471 struct kobj_attribute *attr,
472 const char *buf, size_t n)
473{
474 suspend_state_t state = decode_state(buf, n);
475 int error;
476
477 if (state == PM_SUSPEND_ON
478 && strcmp(buf, "off") && strcmp(buf, "off\n"))
479 return -EINVAL;
480
481 error = pm_autosleep_set_state(state);
482 return error ? error : n;
483}
484
485power_attr(autosleep);
486#endif /* CONFIG_PM_AUTOSLEEP */
487
488#ifdef CONFIG_PM_WAKELOCKS
489static ssize_t wake_lock_show(struct kobject *kobj,
490 struct kobj_attribute *attr,
491 char *buf)
492{
493 return pm_show_wakelocks(buf, true);
494}
495
496static ssize_t wake_lock_store(struct kobject *kobj,
497 struct kobj_attribute *attr,
498 const char *buf, size_t n)
499{
500 int error = pm_wake_lock(buf);
501 return error ? error : n;
502}
503
504power_attr(wake_lock);
505
506static ssize_t wake_unlock_show(struct kobject *kobj,
507 struct kobj_attribute *attr,
508 char *buf)
509{
510 return pm_show_wakelocks(buf, false);
511}
512
513static ssize_t wake_unlock_store(struct kobject *kobj,
514 struct kobj_attribute *attr,
515 const char *buf, size_t n)
516{
517 int error = pm_wake_unlock(buf);
518 return error ? error : n;
519}
520
521power_attr(wake_unlock);
522
523#endif /* CONFIG_PM_WAKELOCKS */
524#endif /* CONFIG_PM_SLEEP */
525
526#ifdef CONFIG_PM_TRACE
527int pm_trace_enabled;
528
529static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
530 char *buf)
531{
532 return sprintf(buf, "%d\n", pm_trace_enabled);
533}
534
535static ssize_t
536pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
537 const char *buf, size_t n)
538{
539 int val;
540
541 if (sscanf(buf, "%d", &val) == 1) {
542 pm_trace_enabled = !!val;
543 if (pm_trace_enabled) {
544 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
545 "PM: Correct system time has to be restored manually after resume.\n");
546 }
547 return n;
548 }
549 return -EINVAL;
550}
551
552power_attr(pm_trace);
553
554static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
555 struct kobj_attribute *attr,
556 char *buf)
557{
558 return show_trace_dev_match(buf, PAGE_SIZE);
559}
560
561power_attr_ro(pm_trace_dev_match);
562
563#endif /* CONFIG_PM_TRACE */
564
565#ifdef CONFIG_FREEZER
566static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
567 struct kobj_attribute *attr, char *buf)
568{
569 return sprintf(buf, "%u\n", freeze_timeout_msecs);
570}
571
572static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
573 struct kobj_attribute *attr,
574 const char *buf, size_t n)
575{
576 unsigned long val;
577
578 if (kstrtoul(buf, 10, &val))
579 return -EINVAL;
580
581 freeze_timeout_msecs = val;
582 return n;
583}
584
585power_attr(pm_freeze_timeout);
586
587#endif /* CONFIG_FREEZER*/
588
589static struct attribute * g[] = {
590 &state_attr.attr,
591#ifdef CONFIG_PM_TRACE
592 &pm_trace_attr.attr,
593 &pm_trace_dev_match_attr.attr,
594#endif
595#ifdef CONFIG_PM_SLEEP
596 &pm_async_attr.attr,
597 &wakeup_count_attr.attr,
598#ifdef CONFIG_PM_AUTOSLEEP
599 &autosleep_attr.attr,
600#endif
601#ifdef CONFIG_PM_WAKELOCKS
602 &wake_lock_attr.attr,
603 &wake_unlock_attr.attr,
604#endif
605#ifdef CONFIG_PM_DEBUG
606 &pm_test_attr.attr,
607#endif
608#ifdef CONFIG_PM_SLEEP_DEBUG
609 &pm_print_times_attr.attr,
610 &pm_wakeup_irq_attr.attr,
611#endif
612#endif
613#ifdef CONFIG_FREEZER
614 &pm_freeze_timeout_attr.attr,
615#endif
616 NULL,
617};
618
619static struct attribute_group attr_group = {
620 .attrs = g,
621};
622
623struct workqueue_struct *pm_wq;
624EXPORT_SYMBOL_GPL(pm_wq);
625
626static int __init pm_start_workqueue(void)
627{
628 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
629
630 return pm_wq ? 0 : -ENOMEM;
631}
632
633static int __init pm_init(void)
634{
635 int error = pm_start_workqueue();
636 if (error)
637 return error;
638 hibernate_image_size_init();
639 hibernate_reserved_size_init();
640 power_kobj = kobject_create_and_add("power", NULL);
641 if (!power_kobj)
642 return -ENOMEM;
643 error = sysfs_create_group(power_kobj, &attr_group);
644 if (error)
645 return error;
646 pm_print_times_init();
647 return pm_autosleep_init();
648}
649
650core_initcall(pm_init);