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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * kernel/power/main.c - PM subsystem core functionality.
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
Srivatsa S. Bhat341d4162011-11-19 14:39:01 +01006 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * This file is released under the GPLv2
8 *
9 */
10
Paul Gortmaker6e5fdee2011-05-26 16:00:52 -040011#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/kobject.h>
13#include <linux/string.h>
Zhonghui Fu431d4522015-03-18 15:54:27 +010014#include <linux/pm-trace.h>
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +020015#include <linux/workqueue.h>
ShuoX Liu2a77c462011-08-10 23:01:26 +020016#include <linux/debugfs.h>
17#include <linux/seq_file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018
19#include "power.h"
20
Stephen Hemmingera6d70982006-12-06 20:34:35 -080021DEFINE_MUTEX(pm_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070022
Rafael J. Wysockicd51e61c2011-02-11 00:04:52 +010023#ifdef CONFIG_PM_SLEEP
24
Bart Van Assche4bf236a2018-01-05 09:19:08 -080025void lock_system_sleep(void)
26{
27 current->flags |= PF_FREEZER_SKIP;
28 mutex_lock(&pm_mutex);
29}
30EXPORT_SYMBOL_GPL(lock_system_sleep);
31
32void unlock_system_sleep(void)
33{
34 /*
35 * Don't use freezer_count() because we don't want the call to
36 * try_to_freeze() here.
37 *
38 * Reason:
39 * Fundamentally, we just don't need it, because freezing condition
40 * doesn't come into effect until we release the pm_mutex lock,
41 * since the freezer always works with pm_mutex held.
42 *
43 * More importantly, in the case of hibernation,
44 * unlock_system_sleep() gets called in snapshot_read() and
45 * snapshot_write() when the freezing condition is still in effect.
46 * Which means, if we use try_to_freeze() here, it would make them
47 * enter the refrigerator, thus causing hibernation to lockup.
48 */
49 current->flags &= ~PF_FREEZER_SKIP;
50 mutex_unlock(&pm_mutex);
51}
52EXPORT_SYMBOL_GPL(unlock_system_sleep);
53
Alan Stern82525752007-11-19 23:49:18 +010054/* Routines for PM-transition notifications */
55
56static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
57
58int register_pm_notifier(struct notifier_block *nb)
59{
60 return blocking_notifier_chain_register(&pm_chain_head, nb);
61}
62EXPORT_SYMBOL_GPL(register_pm_notifier);
63
64int unregister_pm_notifier(struct notifier_block *nb)
65{
66 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
67}
68EXPORT_SYMBOL_GPL(unregister_pm_notifier);
69
Lianwei Wangea00f4f2016-06-19 23:52:27 -070070int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
Alan Stern82525752007-11-19 23:49:18 +010071{
Lianwei Wangea00f4f2016-06-19 23:52:27 -070072 int ret;
73
74 ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
75 nr_to_call, nr_calls);
Akinobu Mitaf0c077a2011-07-08 20:53:36 +020076
77 return notifier_to_errno(ret);
Alan Stern82525752007-11-19 23:49:18 +010078}
Lianwei Wangea00f4f2016-06-19 23:52:27 -070079int pm_notifier_call_chain(unsigned long val)
80{
81 return __pm_notifier_call_chain(val, -1, NULL);
82}
Alan Stern82525752007-11-19 23:49:18 +010083
Rafael J. Wysocki0e06b4a2010-01-23 22:25:15 +010084/* If set, devices may be suspended and resumed asynchronously. */
85int pm_async_enabled = 1;
86
87static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
88 char *buf)
89{
90 return sprintf(buf, "%d\n", pm_async_enabled);
91}
92
93static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
94 const char *buf, size_t n)
95{
96 unsigned long val;
97
Daniel Walter883ee4f2012-10-23 01:20:35 +020098 if (kstrtoul(buf, 10, &val))
Rafael J. Wysocki0e06b4a2010-01-23 22:25:15 +010099 return -EINVAL;
100
101 if (val > 1)
102 return -EINVAL;
103
104 pm_async_enabled = val;
105 return n;
106}
107
108power_attr(pm_async);
109
Rafael J. Wysocki406e7932016-11-21 22:45:40 +0100110#ifdef CONFIG_SUSPEND
111static ssize_t mem_sleep_show(struct kobject *kobj, struct kobj_attribute *attr,
112 char *buf)
113{
114 char *s = buf;
115 suspend_state_t i;
116
117 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
118 if (mem_sleep_states[i]) {
119 const char *label = mem_sleep_states[i];
120
121 if (mem_sleep_current == i)
122 s += sprintf(s, "[%s] ", label);
123 else
124 s += sprintf(s, "%s ", label);
125 }
126
127 /* Convert the last space to a newline if needed. */
128 if (s != buf)
129 *(s-1) = '\n';
130
131 return (s - buf);
132}
133
134static suspend_state_t decode_suspend_state(const char *buf, size_t n)
135{
136 suspend_state_t state;
137 char *p;
138 int len;
139
140 p = memchr(buf, '\n', n);
141 len = p ? p - buf : n;
142
143 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
144 const char *label = mem_sleep_states[state];
145
146 if (label && len == strlen(label) && !strncmp(buf, label, len))
147 return state;
148 }
149
150 return PM_SUSPEND_ON;
151}
152
153static ssize_t mem_sleep_store(struct kobject *kobj, struct kobj_attribute *attr,
154 const char *buf, size_t n)
155{
156 suspend_state_t state;
157 int error;
158
159 error = pm_autosleep_lock();
160 if (error)
161 return error;
162
163 if (pm_autosleep_state() > PM_SUSPEND_ON) {
164 error = -EBUSY;
165 goto out;
166 }
167
168 state = decode_suspend_state(buf, n);
169 if (state < PM_SUSPEND_MAX && state > PM_SUSPEND_ON)
170 mem_sleep_current = state;
171 else
172 error = -EINVAL;
173
174 out:
175 pm_autosleep_unlock();
176 return error ? error : n;
177}
178
179power_attr(mem_sleep);
180#endif /* CONFIG_SUSPEND */
181
Rafael J. Wysockie516a1d2017-07-21 14:44:02 +0200182#ifdef CONFIG_PM_SLEEP_DEBUG
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100183int pm_test_level = TEST_NONE;
184
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100185static const char * const pm_tests[__TEST_AFTER_LAST] = {
186 [TEST_NONE] = "none",
187 [TEST_CORE] = "core",
188 [TEST_CPUS] = "processors",
189 [TEST_PLATFORM] = "platform",
190 [TEST_DEVICES] = "devices",
191 [TEST_FREEZER] = "freezer",
192};
193
Rafael J. Wysocki039a75c2008-01-29 00:29:06 +0100194static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
195 char *buf)
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100196{
197 char *s = buf;
198 int level;
199
200 for (level = TEST_FIRST; level <= TEST_MAX; level++)
201 if (pm_tests[level]) {
202 if (level == pm_test_level)
203 s += sprintf(s, "[%s] ", pm_tests[level]);
204 else
205 s += sprintf(s, "%s ", pm_tests[level]);
206 }
207
208 if (s != buf)
209 /* convert the last space to a newline */
210 *(s-1) = '\n';
211
212 return (s - buf);
213}
214
Rafael J. Wysocki039a75c2008-01-29 00:29:06 +0100215static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
216 const char *buf, size_t n)
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100217{
218 const char * const *s;
219 int level;
220 char *p;
221 int len;
222 int error = -EINVAL;
223
224 p = memchr(buf, '\n', n);
225 len = p ? p - buf : n;
226
Srivatsa S. Bhatbcda53f2011-12-07 22:29:54 +0100227 lock_system_sleep();
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100228
229 level = TEST_FIRST;
230 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
231 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
232 pm_test_level = level;
233 error = 0;
234 break;
235 }
236
Srivatsa S. Bhatbcda53f2011-12-07 22:29:54 +0100237 unlock_system_sleep();
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100238
239 return error ? error : n;
240}
241
242power_attr(pm_test);
Rafael J. Wysockie516a1d2017-07-21 14:44:02 +0200243#endif /* CONFIG_PM_SLEEP_DEBUG */
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100244
ShuoX Liu2a77c462011-08-10 23:01:26 +0200245#ifdef CONFIG_DEBUG_FS
246static char *suspend_step_name(enum suspend_stat_step step)
247{
248 switch (step) {
249 case SUSPEND_FREEZE:
250 return "freeze";
251 case SUSPEND_PREPARE:
252 return "prepare";
253 case SUSPEND_SUSPEND:
254 return "suspend";
255 case SUSPEND_SUSPEND_NOIRQ:
256 return "suspend_noirq";
257 case SUSPEND_RESUME_NOIRQ:
258 return "resume_noirq";
259 case SUSPEND_RESUME:
260 return "resume";
261 default:
262 return "";
263 }
264}
265
266static int suspend_stats_show(struct seq_file *s, void *unused)
267{
268 int i, index, last_dev, last_errno, last_step;
269
270 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
271 last_dev %= REC_FAILED_NUM;
272 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
273 last_errno %= REC_FAILED_NUM;
274 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
275 last_step %= REC_FAILED_NUM;
Rafael J. Wysockicf579df2012-01-29 20:38:29 +0100276 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
277 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
ShuoX Liu2a77c462011-08-10 23:01:26 +0200278 "success", suspend_stats.success,
279 "fail", suspend_stats.fail,
280 "failed_freeze", suspend_stats.failed_freeze,
281 "failed_prepare", suspend_stats.failed_prepare,
282 "failed_suspend", suspend_stats.failed_suspend,
Rafael J. Wysockicf579df2012-01-29 20:38:29 +0100283 "failed_suspend_late",
284 suspend_stats.failed_suspend_late,
ShuoX Liu2a77c462011-08-10 23:01:26 +0200285 "failed_suspend_noirq",
286 suspend_stats.failed_suspend_noirq,
287 "failed_resume", suspend_stats.failed_resume,
Rafael J. Wysockicf579df2012-01-29 20:38:29 +0100288 "failed_resume_early",
289 suspend_stats.failed_resume_early,
ShuoX Liu2a77c462011-08-10 23:01:26 +0200290 "failed_resume_noirq",
291 suspend_stats.failed_resume_noirq);
292 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
293 suspend_stats.failed_devs[last_dev]);
294 for (i = 1; i < REC_FAILED_NUM; i++) {
295 index = last_dev + REC_FAILED_NUM - i;
296 index %= REC_FAILED_NUM;
297 seq_printf(s, "\t\t\t%-s\n",
298 suspend_stats.failed_devs[index]);
299 }
300 seq_printf(s, " last_failed_errno:\t%-d\n",
301 suspend_stats.errno[last_errno]);
302 for (i = 1; i < REC_FAILED_NUM; i++) {
303 index = last_errno + REC_FAILED_NUM - i;
304 index %= REC_FAILED_NUM;
305 seq_printf(s, "\t\t\t%-d\n",
306 suspend_stats.errno[index]);
307 }
308 seq_printf(s, " last_failed_step:\t%-s\n",
309 suspend_step_name(
310 suspend_stats.failed_steps[last_step]));
311 for (i = 1; i < REC_FAILED_NUM; i++) {
312 index = last_step + REC_FAILED_NUM - i;
313 index %= REC_FAILED_NUM;
314 seq_printf(s, "\t\t\t%-s\n",
315 suspend_step_name(
316 suspend_stats.failed_steps[index]));
317 }
318
319 return 0;
320}
321
322static int suspend_stats_open(struct inode *inode, struct file *file)
323{
324 return single_open(file, suspend_stats_show, NULL);
325}
326
327static const struct file_operations suspend_stats_operations = {
328 .open = suspend_stats_open,
329 .read = seq_read,
330 .llseek = seq_lseek,
331 .release = single_release,
332};
333
334static int __init pm_debugfs_init(void)
335{
336 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
337 NULL, NULL, &suspend_stats_operations);
338 return 0;
339}
340
341late_initcall(pm_debugfs_init);
342#endif /* CONFIG_DEBUG_FS */
343
Rafael J. Wysockica123102011-08-11 22:38:12 +0200344#endif /* CONFIG_PM_SLEEP */
345
Rafael J. Wysockib2df1d42012-06-21 00:19:33 +0200346#ifdef CONFIG_PM_SLEEP_DEBUG
347/*
348 * pm_print_times: print time taken by devices to suspend and resume.
349 *
350 * show() returns whether printing of suspend and resume times is enabled.
351 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
352 */
353bool pm_print_times_enabled;
354
355static ssize_t pm_print_times_show(struct kobject *kobj,
356 struct kobj_attribute *attr, char *buf)
357{
358 return sprintf(buf, "%d\n", pm_print_times_enabled);
359}
360
361static ssize_t pm_print_times_store(struct kobject *kobj,
362 struct kobj_attribute *attr,
363 const char *buf, size_t n)
364{
365 unsigned long val;
366
367 if (kstrtoul(buf, 10, &val))
368 return -EINVAL;
369
370 if (val > 1)
371 return -EINVAL;
372
373 pm_print_times_enabled = !!val;
374 return n;
375}
376
377power_attr(pm_print_times);
378
379static inline void pm_print_times_init(void)
380{
381 pm_print_times_enabled = !!initcall_debug;
382}
Alexandra Yatesa6f5f0d2015-09-15 10:32:46 -0700383
384static ssize_t pm_wakeup_irq_show(struct kobject *kobj,
385 struct kobj_attribute *attr,
386 char *buf)
387{
388 return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA;
389}
390
Rafael J. Wysockia1e9ca62016-01-02 03:09:16 +0100391power_attr_ro(pm_wakeup_irq);
Alexandra Yatesa6f5f0d2015-09-15 10:32:46 -0700392
Srinivas Pandruvada726fb6b2017-08-15 18:16:59 -0700393bool pm_debug_messages_on __read_mostly;
Rafael J. Wysocki8d8b2442017-07-19 02:38:44 +0200394
395static ssize_t pm_debug_messages_show(struct kobject *kobj,
396 struct kobj_attribute *attr, char *buf)
397{
398 return sprintf(buf, "%d\n", pm_debug_messages_on);
399}
400
401static ssize_t pm_debug_messages_store(struct kobject *kobj,
402 struct kobj_attribute *attr,
403 const char *buf, size_t n)
404{
405 unsigned long val;
406
407 if (kstrtoul(buf, 10, &val))
408 return -EINVAL;
409
410 if (val > 1)
411 return -EINVAL;
412
413 pm_debug_messages_on = !!val;
414 return n;
415}
416
417power_attr(pm_debug_messages);
418
419/**
Rafael J. Wysockicb08e032017-07-23 00:03:43 +0200420 * __pm_pr_dbg - Print a suspend debug message to the kernel log.
421 * @defer: Whether or not to use printk_deferred() to print the message.
Rafael J. Wysocki8d8b2442017-07-19 02:38:44 +0200422 * @fmt: Message format.
423 *
424 * The message will be emitted if enabled through the pm_debug_messages
425 * sysfs attribute.
426 */
Rafael J. Wysockicb08e032017-07-23 00:03:43 +0200427void __pm_pr_dbg(bool defer, const char *fmt, ...)
Rafael J. Wysocki8d8b2442017-07-19 02:38:44 +0200428{
429 struct va_format vaf;
430 va_list args;
431
432 if (!pm_debug_messages_on)
433 return;
434
435 va_start(args, fmt);
436
437 vaf.fmt = fmt;
438 vaf.va = &args;
439
Rafael J. Wysockicb08e032017-07-23 00:03:43 +0200440 if (defer)
441 printk_deferred(KERN_DEBUG "PM: %pV", &vaf);
442 else
443 printk(KERN_DEBUG "PM: %pV", &vaf);
Rafael J. Wysocki8d8b2442017-07-19 02:38:44 +0200444
445 va_end(args);
446}
447
Rafael J. Wysocki819b1bb2015-05-13 15:31:12 +0200448#else /* !CONFIG_PM_SLEEP_DEBUG */
Rafael J. Wysockib2df1d42012-06-21 00:19:33 +0200449static inline void pm_print_times_init(void) {}
450#endif /* CONFIG_PM_SLEEP_DEBUG */
451
Greg Kroah-Hartmand76e15f2007-11-27 11:28:26 -0800452struct kobject *power_kobj;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453
454/**
Rafael J. Wysocki0399d4d2014-05-26 13:40:59 +0200455 * state - control system sleep states.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 *
Rafael J. Wysocki0399d4d2014-05-26 13:40:59 +0200457 * show() returns available sleep state labels, which may be "mem", "standby",
458 * "freeze" and "disk" (hibernation). See Documentation/power/states.txt for a
459 * description of what they mean.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 *
Rafael J. Wysocki0399d4d2014-05-26 13:40:59 +0200461 * store() accepts one of those strings, translates it into the proper
462 * enumerated value, and initiates a suspend transition.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 */
Kay Sievers386f2752007-11-02 13:47:53 +0100464static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
465 char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466{
Rafael J. Wysocki296699d2007-07-29 23:27:18 +0200467 char *s = buf;
468#ifdef CONFIG_SUSPEND
Rafael J. Wysocki27ddcc62014-05-26 13:40:47 +0200469 suspend_state_t i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470
Rafael J. Wysocki27ddcc62014-05-26 13:40:47 +0200471 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
Rafael J. Wysockid431cbc2014-07-15 22:02:11 +0200472 if (pm_states[i])
473 s += sprintf(s,"%s ", pm_states[i]);
Rafael J. Wysocki27ddcc62014-05-26 13:40:47 +0200474
Rafael J. Wysocki296699d2007-07-29 23:27:18 +0200475#endif
Kees Cooka6e15a32014-06-13 13:30:35 -0700476 if (hibernation_available())
477 s += sprintf(s, "disk ");
Rafael J. Wysockia3d25c22007-05-09 02:33:18 -0700478 if (s != buf)
479 /* convert the last space to a newline */
480 *(s-1) = '\n';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 return (s - buf);
482}
483
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200484static suspend_state_t decode_state(const char *buf, size_t n)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485{
Rafael J. Wysocki296699d2007-07-29 23:27:18 +0200486#ifdef CONFIG_SUSPEND
Rafael J. Wysockid431cbc2014-07-15 22:02:11 +0200487 suspend_state_t state;
Rafael J. Wysocki296699d2007-07-29 23:27:18 +0200488#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 char *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 int len;
491
492 p = memchr(buf, '\n', n);
493 len = p ? p - buf : n;
494
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200495 /* Check hibernation first. */
496 if (len == 4 && !strncmp(buf, "disk", len))
497 return PM_SUSPEND_MAX;
Rafael J. Wysockia3d25c22007-05-09 02:33:18 -0700498
Rafael J. Wysocki296699d2007-07-29 23:27:18 +0200499#ifdef CONFIG_SUSPEND
Rafael J. Wysockid431cbc2014-07-15 22:02:11 +0200500 for (state = PM_SUSPEND_MIN; state < PM_SUSPEND_MAX; state++) {
501 const char *label = pm_states[state];
502
503 if (label && len == strlen(label) && !strncmp(buf, label, len))
504 return state;
505 }
Rafael J. Wysocki296699d2007-07-29 23:27:18 +0200506#endif
507
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200508 return PM_SUSPEND_ON;
509}
510
511static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
512 const char *buf, size_t n)
513{
514 suspend_state_t state;
515 int error;
516
517 error = pm_autosleep_lock();
518 if (error)
519 return error;
520
521 if (pm_autosleep_state() > PM_SUSPEND_ON) {
522 error = -EBUSY;
523 goto out;
524 }
525
526 state = decode_state(buf, n);
Rafael J. Wysocki406e7932016-11-21 22:45:40 +0100527 if (state < PM_SUSPEND_MAX) {
528 if (state == PM_SUSPEND_MEM)
529 state = mem_sleep_current;
530
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200531 error = pm_suspend(state);
Rafael J. Wysocki406e7932016-11-21 22:45:40 +0100532 } else if (state == PM_SUSPEND_MAX) {
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200533 error = hibernate();
Rafael J. Wysocki406e7932016-11-21 22:45:40 +0100534 } else {
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200535 error = -EINVAL;
Rafael J. Wysocki406e7932016-11-21 22:45:40 +0100536 }
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200537
538 out:
539 pm_autosleep_unlock();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 return error ? error : n;
541}
542
543power_attr(state);
544
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200545#ifdef CONFIG_PM_SLEEP
546/*
547 * The 'wakeup_count' attribute, along with the functions defined in
548 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
549 * handled in a non-racy way.
550 *
551 * If a wakeup event occurs when the system is in a sleep state, it simply is
552 * woken up. In turn, if an event that would wake the system up from a sleep
553 * state occurs when it is undergoing a transition to that sleep state, the
554 * transition should be aborted. Moreover, if such an event occurs when the
555 * system is in the working state, an attempt to start a transition to the
556 * given sleep state should fail during certain period after the detection of
557 * the event. Using the 'state' attribute alone is not sufficient to satisfy
558 * these requirements, because a wakeup event may occur exactly when 'state'
559 * is being written to and may be delivered to user space right before it is
560 * frozen, so the event will remain only partially processed until the system is
561 * woken up by another event. In particular, it won't cause the transition to
562 * a sleep state to be aborted.
563 *
564 * This difficulty may be overcome if user space uses 'wakeup_count' before
565 * writing to 'state'. It first should read from 'wakeup_count' and store
566 * the read value. Then, after carrying out its own preparations for the system
567 * transition to a sleep state, it should write the stored value to
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300568 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200569 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
570 * is allowed to write to 'state', but the transition will be aborted if there
571 * are any wakeup events detected after 'wakeup_count' was written to.
572 */
573
574static ssize_t wakeup_count_show(struct kobject *kobj,
575 struct kobj_attribute *attr,
576 char *buf)
577{
Rafael J. Wysocki074037e2010-09-22 22:09:10 +0200578 unsigned int val;
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200579
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200580 return pm_get_wakeup_count(&val, true) ?
581 sprintf(buf, "%u\n", val) : -EINTR;
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200582}
583
584static ssize_t wakeup_count_store(struct kobject *kobj,
585 struct kobj_attribute *attr,
586 const char *buf, size_t n)
587{
Rafael J. Wysocki074037e2010-09-22 22:09:10 +0200588 unsigned int val;
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200589 int error;
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200590
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200591 error = pm_autosleep_lock();
592 if (error)
593 return error;
594
595 if (pm_autosleep_state() > PM_SUSPEND_ON) {
596 error = -EBUSY;
597 goto out;
598 }
599
600 error = -EINVAL;
Rafael J. Wysocki074037e2010-09-22 22:09:10 +0200601 if (sscanf(buf, "%u", &val) == 1) {
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200602 if (pm_save_wakeup_count(val))
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200603 error = n;
Julius Wernerbb177fe2013-06-12 12:55:22 -0700604 else
605 pm_print_active_wakeup_sources();
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200606 }
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200607
608 out:
609 pm_autosleep_unlock();
610 return error;
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200611}
612
613power_attr(wakeup_count);
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200614
615#ifdef CONFIG_PM_AUTOSLEEP
616static ssize_t autosleep_show(struct kobject *kobj,
617 struct kobj_attribute *attr,
618 char *buf)
619{
620 suspend_state_t state = pm_autosleep_state();
621
622 if (state == PM_SUSPEND_ON)
623 return sprintf(buf, "off\n");
624
625#ifdef CONFIG_SUSPEND
626 if (state < PM_SUSPEND_MAX)
Rafael J. Wysockid431cbc2014-07-15 22:02:11 +0200627 return sprintf(buf, "%s\n", pm_states[state] ?
628 pm_states[state] : "error");
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200629#endif
630#ifdef CONFIG_HIBERNATION
631 return sprintf(buf, "disk\n");
632#else
633 return sprintf(buf, "error");
634#endif
635}
636
637static ssize_t autosleep_store(struct kobject *kobj,
638 struct kobj_attribute *attr,
639 const char *buf, size_t n)
640{
641 suspend_state_t state = decode_state(buf, n);
642 int error;
643
644 if (state == PM_SUSPEND_ON
Arve Hjønnevåg040e5bf2012-05-04 00:14:21 +0200645 && strcmp(buf, "off") && strcmp(buf, "off\n"))
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200646 return -EINVAL;
647
Rafael J. Wysocki406e7932016-11-21 22:45:40 +0100648 if (state == PM_SUSPEND_MEM)
649 state = mem_sleep_current;
650
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200651 error = pm_autosleep_set_state(state);
652 return error ? error : n;
653}
654
655power_attr(autosleep);
656#endif /* CONFIG_PM_AUTOSLEEP */
Rafael J. Wysockib86ff9822012-04-29 22:53:42 +0200657
658#ifdef CONFIG_PM_WAKELOCKS
659static ssize_t wake_lock_show(struct kobject *kobj,
660 struct kobj_attribute *attr,
661 char *buf)
662{
663 return pm_show_wakelocks(buf, true);
664}
665
666static ssize_t wake_lock_store(struct kobject *kobj,
667 struct kobj_attribute *attr,
668 const char *buf, size_t n)
669{
670 int error = pm_wake_lock(buf);
671 return error ? error : n;
672}
673
674power_attr(wake_lock);
675
676static ssize_t wake_unlock_show(struct kobject *kobj,
677 struct kobj_attribute *attr,
678 char *buf)
679{
680 return pm_show_wakelocks(buf, false);
681}
682
683static ssize_t wake_unlock_store(struct kobject *kobj,
684 struct kobj_attribute *attr,
685 const char *buf, size_t n)
686{
687 int error = pm_wake_unlock(buf);
688 return error ? error : n;
689}
690
691power_attr(wake_unlock);
692
693#endif /* CONFIG_PM_WAKELOCKS */
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200694#endif /* CONFIG_PM_SLEEP */
695
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700696#ifdef CONFIG_PM_TRACE
697int pm_trace_enabled;
698
Kay Sievers386f2752007-11-02 13:47:53 +0100699static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
700 char *buf)
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700701{
702 return sprintf(buf, "%d\n", pm_trace_enabled);
703}
704
705static ssize_t
Kay Sievers386f2752007-11-02 13:47:53 +0100706pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
707 const char *buf, size_t n)
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700708{
709 int val;
710
711 if (sscanf(buf, "%d", &val) == 1) {
712 pm_trace_enabled = !!val;
Shuah Khan9dceefe2013-06-26 16:27:35 -0600713 if (pm_trace_enabled) {
714 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
715 "PM: Correct system time has to be restored manually after resume.\n");
716 }
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700717 return n;
718 }
719 return -EINVAL;
720}
721
722power_attr(pm_trace);
James Hogand33ac602010-10-12 00:00:25 +0200723
724static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
725 struct kobj_attribute *attr,
726 char *buf)
727{
728 return show_trace_dev_match(buf, PAGE_SIZE);
729}
730
Rafael J. Wysockia1e9ca62016-01-02 03:09:16 +0100731power_attr_ro(pm_trace_dev_match);
James Hogand33ac602010-10-12 00:00:25 +0200732
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100733#endif /* CONFIG_PM_TRACE */
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700734
Li Fei957d1282013-02-01 08:56:03 +0000735#ifdef CONFIG_FREEZER
736static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
737 struct kobj_attribute *attr, char *buf)
738{
739 return sprintf(buf, "%u\n", freeze_timeout_msecs);
740}
741
742static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
743 struct kobj_attribute *attr,
744 const char *buf, size_t n)
745{
746 unsigned long val;
747
748 if (kstrtoul(buf, 10, &val))
749 return -EINVAL;
750
751 freeze_timeout_msecs = val;
752 return n;
753}
754
755power_attr(pm_freeze_timeout);
756
757#endif /* CONFIG_FREEZER*/
758
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700759static struct attribute * g[] = {
760 &state_attr.attr,
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100761#ifdef CONFIG_PM_TRACE
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700762 &pm_trace_attr.attr,
James Hogand33ac602010-10-12 00:00:25 +0200763 &pm_trace_dev_match_attr.attr,
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100764#endif
Rafael J. Wysocki0e06b4a2010-01-23 22:25:15 +0100765#ifdef CONFIG_PM_SLEEP
766 &pm_async_attr.attr,
Rafael J. Wysockic125e962010-07-05 22:43:53 +0200767 &wakeup_count_attr.attr,
Rafael J. Wysocki406e7932016-11-21 22:45:40 +0100768#ifdef CONFIG_SUSPEND
769 &mem_sleep_attr.attr,
770#endif
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200771#ifdef CONFIG_PM_AUTOSLEEP
772 &autosleep_attr.attr,
773#endif
Rafael J. Wysockib86ff9822012-04-29 22:53:42 +0200774#ifdef CONFIG_PM_WAKELOCKS
775 &wake_lock_attr.attr,
776 &wake_unlock_attr.attr,
777#endif
Rafael J. Wysockib2df1d42012-06-21 00:19:33 +0200778#ifdef CONFIG_PM_SLEEP_DEBUG
Rafael J. Wysockie516a1d2017-07-21 14:44:02 +0200779 &pm_test_attr.attr,
Sameer Nanda4b7760b2012-06-19 22:23:33 +0200780 &pm_print_times_attr.attr,
Alexandra Yatesa6f5f0d2015-09-15 10:32:46 -0700781 &pm_wakeup_irq_attr.attr,
Rafael J. Wysocki8d8b2442017-07-19 02:38:44 +0200782 &pm_debug_messages_attr.attr,
Rafael J. Wysocki0e7d56e2007-11-19 23:41:19 +0100783#endif
Rafael J. Wysocki0e06b4a2010-01-23 22:25:15 +0100784#endif
Li Fei957d1282013-02-01 08:56:03 +0000785#ifdef CONFIG_FREEZER
786 &pm_freeze_timeout_attr.attr,
787#endif
Rafael J. Wysockic5c6ba42006-09-25 23:32:58 -0700788 NULL,
789};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790
Arvind Yadav1d0c6e52017-06-30 10:22:14 +0530791static const struct attribute_group attr_group = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 .attrs = g,
793};
794
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200795struct workqueue_struct *pm_wq;
Alan Stern7b199ca2009-12-03 20:22:21 +0100796EXPORT_SYMBOL_GPL(pm_wq);
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200797
798static int __init pm_start_workqueue(void)
799{
Tejun Heo58a69cb2011-02-16 09:25:31 +0100800 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200801
802 return pm_wq ? 0 : -ENOMEM;
803}
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200804
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805static int __init pm_init(void)
806{
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200807 int error = pm_start_workqueue();
808 if (error)
809 return error;
Rafael J. Wysockiac5c24ec2010-09-20 19:44:56 +0200810 hibernate_image_size_init();
Rafael J. Wysockiddeb6482011-05-15 11:38:48 +0200811 hibernate_reserved_size_init();
Sudeep Hollafa7fd6f2016-08-19 14:41:00 +0100812 pm_states_init();
Greg Kroah-Hartmand76e15f2007-11-27 11:28:26 -0800813 power_kobj = kobject_create_and_add("power", NULL);
814 if (!power_kobj)
Greg Kroah-Hartman039a5dc2007-11-01 10:39:50 -0700815 return -ENOMEM;
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200816 error = sysfs_create_group(power_kobj, &attr_group);
817 if (error)
818 return error;
Rafael J. Wysockib2df1d42012-06-21 00:19:33 +0200819 pm_print_times_init();
Rafael J. Wysocki7483b4a2012-04-29 22:53:22 +0200820 return pm_autosleep_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821}
822
823core_initcall(pm_init);