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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/resume-trace.h>
15#include <linux/workqueue.h>
16#include <linux/debugfs.h>
17#include <linux/seq_file.h>
18
19#include "power.h"
20
21DEFINE_MUTEX(pm_mutex);
22
23#ifdef CONFIG_PM_SLEEP
24
25/* Routines for PM-transition notifications */
26
27static BLOCKING_NOTIFIER_HEAD(pm_chain_head);
28
29int register_pm_notifier(struct notifier_block *nb)
30{
31 return blocking_notifier_chain_register(&pm_chain_head, nb);
32}
33EXPORT_SYMBOL_GPL(register_pm_notifier);
34
35int unregister_pm_notifier(struct notifier_block *nb)
36{
37 return blocking_notifier_chain_unregister(&pm_chain_head, nb);
38}
39EXPORT_SYMBOL_GPL(unregister_pm_notifier);
40
41int pm_notifier_call_chain(unsigned long val)
42{
43 int ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL);
44
45 return notifier_to_errno(ret);
46}
47
48/* If set, devices may be suspended and resumed asynchronously. */
49int pm_async_enabled = 1;
50
51static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr,
52 char *buf)
53{
54 return sprintf(buf, "%d\n", pm_async_enabled);
55}
56
57static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr,
58 const char *buf, size_t n)
59{
60 unsigned long val;
61
62 if (kstrtoul(buf, 10, &val))
63 return -EINVAL;
64
65 if (val > 1)
66 return -EINVAL;
67
68 pm_async_enabled = val;
69 return n;
70}
71
72power_attr(pm_async);
73
74#ifdef CONFIG_PM_DEBUG
75int pm_test_level = TEST_NONE;
76
77static const char * const pm_tests[__TEST_AFTER_LAST] = {
78 [TEST_NONE] = "none",
79 [TEST_CORE] = "core",
80 [TEST_CPUS] = "processors",
81 [TEST_PLATFORM] = "platform",
82 [TEST_DEVICES] = "devices",
83 [TEST_FREEZER] = "freezer",
84};
85
86static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
87 char *buf)
88{
89 char *s = buf;
90 int level;
91
92 for (level = TEST_FIRST; level <= TEST_MAX; level++)
93 if (pm_tests[level]) {
94 if (level == pm_test_level)
95 s += sprintf(s, "[%s] ", pm_tests[level]);
96 else
97 s += sprintf(s, "%s ", pm_tests[level]);
98 }
99
100 if (s != buf)
101 /* convert the last space to a newline */
102 *(s-1) = '\n';
103
104 return (s - buf);
105}
106
107static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
108 const char *buf, size_t n)
109{
110 const char * const *s;
111 int level;
112 char *p;
113 int len;
114 int error = -EINVAL;
115
116 p = memchr(buf, '\n', n);
117 len = p ? p - buf : n;
118
119 lock_system_sleep();
120
121 level = TEST_FIRST;
122 for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++)
123 if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) {
124 pm_test_level = level;
125 error = 0;
126 break;
127 }
128
129 unlock_system_sleep();
130
131 return error ? error : n;
132}
133
134power_attr(pm_test);
135#endif /* CONFIG_PM_DEBUG */
136
137#ifdef CONFIG_DEBUG_FS
138static char *suspend_step_name(enum suspend_stat_step step)
139{
140 switch (step) {
141 case SUSPEND_FREEZE:
142 return "freeze";
143 case SUSPEND_PREPARE:
144 return "prepare";
145 case SUSPEND_SUSPEND:
146 return "suspend";
147 case SUSPEND_SUSPEND_NOIRQ:
148 return "suspend_noirq";
149 case SUSPEND_RESUME_NOIRQ:
150 return "resume_noirq";
151 case SUSPEND_RESUME:
152 return "resume";
153 default:
154 return "";
155 }
156}
157
158static int suspend_stats_show(struct seq_file *s, void *unused)
159{
160 int i, index, last_dev, last_errno, last_step;
161
162 last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1;
163 last_dev %= REC_FAILED_NUM;
164 last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1;
165 last_errno %= REC_FAILED_NUM;
166 last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1;
167 last_step %= REC_FAILED_NUM;
168 seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
169 "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n",
170 "success", suspend_stats.success,
171 "fail", suspend_stats.fail,
172 "failed_freeze", suspend_stats.failed_freeze,
173 "failed_prepare", suspend_stats.failed_prepare,
174 "failed_suspend", suspend_stats.failed_suspend,
175 "failed_suspend_late",
176 suspend_stats.failed_suspend_late,
177 "failed_suspend_noirq",
178 suspend_stats.failed_suspend_noirq,
179 "failed_resume", suspend_stats.failed_resume,
180 "failed_resume_early",
181 suspend_stats.failed_resume_early,
182 "failed_resume_noirq",
183 suspend_stats.failed_resume_noirq);
184 seq_printf(s, "failures:\n last_failed_dev:\t%-s\n",
185 suspend_stats.failed_devs[last_dev]);
186 for (i = 1; i < REC_FAILED_NUM; i++) {
187 index = last_dev + REC_FAILED_NUM - i;
188 index %= REC_FAILED_NUM;
189 seq_printf(s, "\t\t\t%-s\n",
190 suspend_stats.failed_devs[index]);
191 }
192 seq_printf(s, " last_failed_errno:\t%-d\n",
193 suspend_stats.errno[last_errno]);
194 for (i = 1; i < REC_FAILED_NUM; i++) {
195 index = last_errno + REC_FAILED_NUM - i;
196 index %= REC_FAILED_NUM;
197 seq_printf(s, "\t\t\t%-d\n",
198 suspend_stats.errno[index]);
199 }
200 seq_printf(s, " last_failed_step:\t%-s\n",
201 suspend_step_name(
202 suspend_stats.failed_steps[last_step]));
203 for (i = 1; i < REC_FAILED_NUM; i++) {
204 index = last_step + REC_FAILED_NUM - i;
205 index %= REC_FAILED_NUM;
206 seq_printf(s, "\t\t\t%-s\n",
207 suspend_step_name(
208 suspend_stats.failed_steps[index]));
209 }
210
211 return 0;
212}
213
214static int suspend_stats_open(struct inode *inode, struct file *file)
215{
216 return single_open(file, suspend_stats_show, NULL);
217}
218
219static const struct file_operations suspend_stats_operations = {
220 .open = suspend_stats_open,
221 .read = seq_read,
222 .llseek = seq_lseek,
223 .release = single_release,
224};
225
226static int __init pm_debugfs_init(void)
227{
228 debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO,
229 NULL, NULL, &suspend_stats_operations);
230 return 0;
231}
232
233late_initcall(pm_debugfs_init);
234#endif /* CONFIG_DEBUG_FS */
235
236#endif /* CONFIG_PM_SLEEP */
237
238#ifdef CONFIG_PM_SLEEP_DEBUG
239/*
240 * pm_print_times: print time taken by devices to suspend and resume.
241 *
242 * show() returns whether printing of suspend and resume times is enabled.
243 * store() accepts 0 or 1. 0 disables printing and 1 enables it.
244 */
245bool pm_print_times_enabled;
246
247static ssize_t pm_print_times_show(struct kobject *kobj,
248 struct kobj_attribute *attr, char *buf)
249{
250 return sprintf(buf, "%d\n", pm_print_times_enabled);
251}
252
253static ssize_t pm_print_times_store(struct kobject *kobj,
254 struct kobj_attribute *attr,
255 const char *buf, size_t n)
256{
257 unsigned long val;
258
259 if (kstrtoul(buf, 10, &val))
260 return -EINVAL;
261
262 if (val > 1)
263 return -EINVAL;
264
265 pm_print_times_enabled = !!val;
266 return n;
267}
268
269power_attr(pm_print_times);
270
271static inline void pm_print_times_init(void)
272{
273 pm_print_times_enabled = !!initcall_debug;
274}
275#else /* !CONFIG_PP_SLEEP_DEBUG */
276static inline void pm_print_times_init(void) {}
277#endif /* CONFIG_PM_SLEEP_DEBUG */
278
279struct kobject *power_kobj;
280
281/**
282 * state - control system power state.
283 *
284 * show() returns what states are supported, which is hard-coded to
285 * 'freeze' (Low-Power Idle), 'standby' (Power-On Suspend),
286 * 'mem' (Suspend-to-RAM), and 'disk' (Suspend-to-Disk).
287 *
288 * store() accepts one of those strings, translates it into the
289 * proper enumerated value, and initiates a suspend transition.
290 */
291static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
292 char *buf)
293{
294 char *s = buf;
295#ifdef CONFIG_SUSPEND
296 int i;
297
298 for (i = 0; i < PM_SUSPEND_MAX; i++) {
299 if (pm_states[i] && valid_state(i))
300 s += sprintf(s,"%s ", pm_states[i]);
301 }
302#endif
303#ifdef CONFIG_HIBERNATION
304 s += sprintf(s, "%s\n", "disk");
305#else
306 if (s != buf)
307 /* convert the last space to a newline */
308 *(s-1) = '\n';
309#endif
310 return (s - buf);
311}
312
313static suspend_state_t decode_state(const char *buf, size_t n)
314{
315#ifdef CONFIG_SUSPEND
316 suspend_state_t state = PM_SUSPEND_MIN;
317 const char * const *s;
318#endif
319 char *p;
320 int len;
321
322 p = memchr(buf, '\n', n);
323 len = p ? p - buf : n;
324
325 /* Check hibernation first. */
326 if (len == 4 && !strncmp(buf, "disk", len))
327 return PM_SUSPEND_MAX;
328
329#ifdef CONFIG_SUSPEND
330 for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++)
331 if (*s && len == strlen(*s) && !strncmp(buf, *s, len))
332 return state;
333#endif
334
335 return PM_SUSPEND_ON;
336}
337
338static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr,
339 const char *buf, size_t n)
340{
341 suspend_state_t state;
342 int error;
343
344 error = pm_autosleep_lock();
345 if (error)
346 return error;
347
348 if (pm_autosleep_state() > PM_SUSPEND_ON) {
349 error = -EBUSY;
350 goto out;
351 }
352
353 state = decode_state(buf, n);
354 if (state < PM_SUSPEND_MAX)
355 error = pm_suspend(state);
356 else if (state == PM_SUSPEND_MAX)
357 error = hibernate();
358 else
359 error = -EINVAL;
360
361 out:
362 pm_autosleep_unlock();
363 return error ? error : n;
364}
365
366power_attr(state);
367
368#ifdef CONFIG_PM_SLEEP
369/*
370 * The 'wakeup_count' attribute, along with the functions defined in
371 * drivers/base/power/wakeup.c, provides a means by which wakeup events can be
372 * handled in a non-racy way.
373 *
374 * If a wakeup event occurs when the system is in a sleep state, it simply is
375 * woken up. In turn, if an event that would wake the system up from a sleep
376 * state occurs when it is undergoing a transition to that sleep state, the
377 * transition should be aborted. Moreover, if such an event occurs when the
378 * system is in the working state, an attempt to start a transition to the
379 * given sleep state should fail during certain period after the detection of
380 * the event. Using the 'state' attribute alone is not sufficient to satisfy
381 * these requirements, because a wakeup event may occur exactly when 'state'
382 * is being written to and may be delivered to user space right before it is
383 * frozen, so the event will remain only partially processed until the system is
384 * woken up by another event. In particular, it won't cause the transition to
385 * a sleep state to be aborted.
386 *
387 * This difficulty may be overcome if user space uses 'wakeup_count' before
388 * writing to 'state'. It first should read from 'wakeup_count' and store
389 * the read value. Then, after carrying out its own preparations for the system
390 * transition to a sleep state, it should write the stored value to
391 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
392 * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it
393 * is allowed to write to 'state', but the transition will be aborted if there
394 * are any wakeup events detected after 'wakeup_count' was written to.
395 */
396
397static ssize_t wakeup_count_show(struct kobject *kobj,
398 struct kobj_attribute *attr,
399 char *buf)
400{
401 unsigned int val;
402
403 return pm_get_wakeup_count(&val, true) ?
404 sprintf(buf, "%u\n", val) : -EINTR;
405}
406
407static ssize_t wakeup_count_store(struct kobject *kobj,
408 struct kobj_attribute *attr,
409 const char *buf, size_t n)
410{
411 unsigned int val;
412 int error;
413
414 error = pm_autosleep_lock();
415 if (error)
416 return error;
417
418 if (pm_autosleep_state() > PM_SUSPEND_ON) {
419 error = -EBUSY;
420 goto out;
421 }
422
423 error = -EINVAL;
424 if (sscanf(buf, "%u", &val) == 1) {
425 if (pm_save_wakeup_count(val))
426 error = n;
427 else
428 pm_print_active_wakeup_sources();
429 }
430
431 out:
432 pm_autosleep_unlock();
433 return error;
434}
435
436power_attr(wakeup_count);
437
438#ifdef CONFIG_PM_AUTOSLEEP
439static ssize_t autosleep_show(struct kobject *kobj,
440 struct kobj_attribute *attr,
441 char *buf)
442{
443 suspend_state_t state = pm_autosleep_state();
444
445 if (state == PM_SUSPEND_ON)
446 return sprintf(buf, "off\n");
447
448#ifdef CONFIG_SUSPEND
449 if (state < PM_SUSPEND_MAX)
450 return sprintf(buf, "%s\n", valid_state(state) ?
451 pm_states[state] : "error");
452#endif
453#ifdef CONFIG_HIBERNATION
454 return sprintf(buf, "disk\n");
455#else
456 return sprintf(buf, "error");
457#endif
458}
459
460static ssize_t autosleep_store(struct kobject *kobj,
461 struct kobj_attribute *attr,
462 const char *buf, size_t n)
463{
464 suspend_state_t state = decode_state(buf, n);
465 int error;
466
467 if (state == PM_SUSPEND_ON
468 && strcmp(buf, "off") && strcmp(buf, "off\n"))
469 return -EINVAL;
470
471 error = pm_autosleep_set_state(state);
472 return error ? error : n;
473}
474
475power_attr(autosleep);
476#endif /* CONFIG_PM_AUTOSLEEP */
477
478#ifdef CONFIG_PM_WAKELOCKS
479static ssize_t wake_lock_show(struct kobject *kobj,
480 struct kobj_attribute *attr,
481 char *buf)
482{
483 return pm_show_wakelocks(buf, true);
484}
485
486static ssize_t wake_lock_store(struct kobject *kobj,
487 struct kobj_attribute *attr,
488 const char *buf, size_t n)
489{
490 int error = pm_wake_lock(buf);
491 return error ? error : n;
492}
493
494power_attr(wake_lock);
495
496static ssize_t wake_unlock_show(struct kobject *kobj,
497 struct kobj_attribute *attr,
498 char *buf)
499{
500 return pm_show_wakelocks(buf, false);
501}
502
503static ssize_t wake_unlock_store(struct kobject *kobj,
504 struct kobj_attribute *attr,
505 const char *buf, size_t n)
506{
507 int error = pm_wake_unlock(buf);
508 return error ? error : n;
509}
510
511power_attr(wake_unlock);
512
513#endif /* CONFIG_PM_WAKELOCKS */
514#endif /* CONFIG_PM_SLEEP */
515
516#ifdef CONFIG_PM_TRACE
517int pm_trace_enabled;
518
519static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
520 char *buf)
521{
522 return sprintf(buf, "%d\n", pm_trace_enabled);
523}
524
525static ssize_t
526pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
527 const char *buf, size_t n)
528{
529 int val;
530
531 if (sscanf(buf, "%d", &val) == 1) {
532 pm_trace_enabled = !!val;
533 if (pm_trace_enabled) {
534 pr_warn("PM: Enabling pm_trace changes system date and time during resume.\n"
535 "PM: Correct system time has to be restored manually after resume.\n");
536 }
537 return n;
538 }
539 return -EINVAL;
540}
541
542power_attr(pm_trace);
543
544static ssize_t pm_trace_dev_match_show(struct kobject *kobj,
545 struct kobj_attribute *attr,
546 char *buf)
547{
548 return show_trace_dev_match(buf, PAGE_SIZE);
549}
550
551static ssize_t
552pm_trace_dev_match_store(struct kobject *kobj, struct kobj_attribute *attr,
553 const char *buf, size_t n)
554{
555 return -EINVAL;
556}
557
558power_attr(pm_trace_dev_match);
559
560#endif /* CONFIG_PM_TRACE */
561
562#ifdef CONFIG_FREEZER
563static ssize_t pm_freeze_timeout_show(struct kobject *kobj,
564 struct kobj_attribute *attr, char *buf)
565{
566 return sprintf(buf, "%u\n", freeze_timeout_msecs);
567}
568
569static ssize_t pm_freeze_timeout_store(struct kobject *kobj,
570 struct kobj_attribute *attr,
571 const char *buf, size_t n)
572{
573 unsigned long val;
574
575 if (kstrtoul(buf, 10, &val))
576 return -EINVAL;
577
578 freeze_timeout_msecs = val;
579 return n;
580}
581
582power_attr(pm_freeze_timeout);
583
584#endif /* CONFIG_FREEZER*/
585
586static struct attribute * g[] = {
587 &state_attr.attr,
588#ifdef CONFIG_PM_TRACE
589 &pm_trace_attr.attr,
590 &pm_trace_dev_match_attr.attr,
591#endif
592#ifdef CONFIG_PM_SLEEP
593 &pm_async_attr.attr,
594 &wakeup_count_attr.attr,
595#ifdef CONFIG_PM_AUTOSLEEP
596 &autosleep_attr.attr,
597#endif
598#ifdef CONFIG_PM_WAKELOCKS
599 &wake_lock_attr.attr,
600 &wake_unlock_attr.attr,
601#endif
602#ifdef CONFIG_PM_DEBUG
603 &pm_test_attr.attr,
604#endif
605#ifdef CONFIG_PM_SLEEP_DEBUG
606 &pm_print_times_attr.attr,
607#endif
608#endif
609#ifdef CONFIG_FREEZER
610 &pm_freeze_timeout_attr.attr,
611#endif
612 NULL,
613};
614
615static struct attribute_group attr_group = {
616 .attrs = g,
617};
618
619#ifdef CONFIG_PM_RUNTIME
620struct workqueue_struct *pm_wq;
621EXPORT_SYMBOL_GPL(pm_wq);
622
623static int __init pm_start_workqueue(void)
624{
625 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
626
627 return pm_wq ? 0 : -ENOMEM;
628}
629#else
630static inline int pm_start_workqueue(void) { return 0; }
631#endif
632
633static int __init pm_init(void)
634{
635 int error = pm_start_workqueue();
636 if (error)
637 return error;
638 hibernate_image_size_init();
639 hibernate_reserved_size_init();
640 power_kobj = kobject_create_and_add("power", NULL);
641 if (!power_kobj)
642 return -ENOMEM;
643 error = sysfs_create_group(power_kobj, &attr_group);
644 if (error)
645 return error;
646 pm_print_times_init();
647 return pm_autosleep_init();
648}
649
650core_initcall(pm_init);
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
25void 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
54/* 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
70int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
71{
72 int ret;
73
74 ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
75 nr_to_call, nr_calls);
76
77 return notifier_to_errno(ret);
78}
79int pm_notifier_call_chain(unsigned long val)
80{
81 return __pm_notifier_call_chain(val, -1, NULL);
82}
83
84/* 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
98 if (kstrtoul(buf, 10, &val))
99 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
110#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
182#ifdef CONFIG_PM_SLEEP_DEBUG
183int pm_test_level = TEST_NONE;
184
185static 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
194static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr,
195 char *buf)
196{
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
215static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr,
216 const char *buf, size_t n)
217{
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
227 lock_system_sleep();
228
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
237 unlock_system_sleep();
238
239 return error ? error : n;
240}
241
242power_attr(pm_test);
243#endif /* CONFIG_PM_SLEEP_DEBUG */
244
245#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;
276 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",
278 "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,
283 "failed_suspend_late",
284 suspend_stats.failed_suspend_late,
285 "failed_suspend_noirq",
286 suspend_stats.failed_suspend_noirq,
287 "failed_resume", suspend_stats.failed_resume,
288 "failed_resume_early",
289 suspend_stats.failed_resume_early,
290 "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
344#endif /* CONFIG_PM_SLEEP */
345
346#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}
383
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
391power_attr_ro(pm_wakeup_irq);
392
393bool pm_debug_messages_on __read_mostly;
394
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/**
420 * __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.
422 * @fmt: Message format.
423 *
424 * The message will be emitted if enabled through the pm_debug_messages
425 * sysfs attribute.
426 */
427void __pm_pr_dbg(bool defer, const char *fmt, ...)
428{
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
440 if (defer)
441 printk_deferred(KERN_DEBUG "PM: %pV", &vaf);
442 else
443 printk(KERN_DEBUG "PM: %pV", &vaf);
444
445 va_end(args);
446}
447
448#else /* !CONFIG_PM_SLEEP_DEBUG */
449static inline void pm_print_times_init(void) {}
450#endif /* CONFIG_PM_SLEEP_DEBUG */
451
452struct kobject *power_kobj;
453
454/**
455 * state - control system sleep states.
456 *
457 * 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.
460 *
461 * store() accepts one of those strings, translates it into the proper
462 * enumerated value, and initiates a suspend transition.
463 */
464static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
465 char *buf)
466{
467 char *s = buf;
468#ifdef CONFIG_SUSPEND
469 suspend_state_t i;
470
471 for (i = PM_SUSPEND_MIN; i < PM_SUSPEND_MAX; i++)
472 if (pm_states[i])
473 s += sprintf(s,"%s ", pm_states[i]);
474
475#endif
476 if (hibernation_available())
477 s += sprintf(s, "disk ");
478 if (s != buf)
479 /* convert the last space to a newline */
480 *(s-1) = '\n';
481 return (s - buf);
482}
483
484static suspend_state_t decode_state(const char *buf, size_t n)
485{
486#ifdef CONFIG_SUSPEND
487 suspend_state_t state;
488#endif
489 char *p;
490 int len;
491
492 p = memchr(buf, '\n', n);
493 len = p ? p - buf : n;
494
495 /* Check hibernation first. */
496 if (len == 4 && !strncmp(buf, "disk", len))
497 return PM_SUSPEND_MAX;
498
499#ifdef CONFIG_SUSPEND
500 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 }
506#endif
507
508 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);
527 if (state < PM_SUSPEND_MAX) {
528 if (state == PM_SUSPEND_MEM)
529 state = mem_sleep_current;
530
531 error = pm_suspend(state);
532 } else if (state == PM_SUSPEND_MAX) {
533 error = hibernate();
534 } else {
535 error = -EINVAL;
536 }
537
538 out:
539 pm_autosleep_unlock();
540 return error ? error : n;
541}
542
543power_attr(state);
544
545#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
568 * 'wakeup_count'. If that fails, at least one wakeup event has occurred since
569 * '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{
578 unsigned int val;
579
580 return pm_get_wakeup_count(&val, true) ?
581 sprintf(buf, "%u\n", val) : -EINTR;
582}
583
584static ssize_t wakeup_count_store(struct kobject *kobj,
585 struct kobj_attribute *attr,
586 const char *buf, size_t n)
587{
588 unsigned int val;
589 int error;
590
591 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;
601 if (sscanf(buf, "%u", &val) == 1) {
602 if (pm_save_wakeup_count(val))
603 error = n;
604 else
605 pm_print_active_wakeup_sources();
606 }
607
608 out:
609 pm_autosleep_unlock();
610 return error;
611}
612
613power_attr(wakeup_count);
614
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)
627 return sprintf(buf, "%s\n", pm_states[state] ?
628 pm_states[state] : "error");
629#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
645 && strcmp(buf, "off") && strcmp(buf, "off\n"))
646 return -EINVAL;
647
648 if (state == PM_SUSPEND_MEM)
649 state = mem_sleep_current;
650
651 error = pm_autosleep_set_state(state);
652 return error ? error : n;
653}
654
655power_attr(autosleep);
656#endif /* CONFIG_PM_AUTOSLEEP */
657
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 */
694#endif /* CONFIG_PM_SLEEP */
695
696#ifdef CONFIG_PM_TRACE
697int pm_trace_enabled;
698
699static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr,
700 char *buf)
701{
702 return sprintf(buf, "%d\n", pm_trace_enabled);
703}
704
705static ssize_t
706pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr,
707 const char *buf, size_t n)
708{
709 int val;
710
711 if (sscanf(buf, "%d", &val) == 1) {
712 pm_trace_enabled = !!val;
713 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 }
717 return n;
718 }
719 return -EINVAL;
720}
721
722power_attr(pm_trace);
723
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
731power_attr_ro(pm_trace_dev_match);
732
733#endif /* CONFIG_PM_TRACE */
734
735#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
759static struct attribute * g[] = {
760 &state_attr.attr,
761#ifdef CONFIG_PM_TRACE
762 &pm_trace_attr.attr,
763 &pm_trace_dev_match_attr.attr,
764#endif
765#ifdef CONFIG_PM_SLEEP
766 &pm_async_attr.attr,
767 &wakeup_count_attr.attr,
768#ifdef CONFIG_SUSPEND
769 &mem_sleep_attr.attr,
770#endif
771#ifdef CONFIG_PM_AUTOSLEEP
772 &autosleep_attr.attr,
773#endif
774#ifdef CONFIG_PM_WAKELOCKS
775 &wake_lock_attr.attr,
776 &wake_unlock_attr.attr,
777#endif
778#ifdef CONFIG_PM_SLEEP_DEBUG
779 &pm_test_attr.attr,
780 &pm_print_times_attr.attr,
781 &pm_wakeup_irq_attr.attr,
782 &pm_debug_messages_attr.attr,
783#endif
784#endif
785#ifdef CONFIG_FREEZER
786 &pm_freeze_timeout_attr.attr,
787#endif
788 NULL,
789};
790
791static const struct attribute_group attr_group = {
792 .attrs = g,
793};
794
795struct workqueue_struct *pm_wq;
796EXPORT_SYMBOL_GPL(pm_wq);
797
798static int __init pm_start_workqueue(void)
799{
800 pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0);
801
802 return pm_wq ? 0 : -ENOMEM;
803}
804
805static int __init pm_init(void)
806{
807 int error = pm_start_workqueue();
808 if (error)
809 return error;
810 hibernate_image_size_init();
811 hibernate_reserved_size_init();
812 pm_states_init();
813 power_kobj = kobject_create_and_add("power", NULL);
814 if (!power_kobj)
815 return -ENOMEM;
816 error = sysfs_create_group(power_kobj, &attr_group);
817 if (error)
818 return error;
819 pm_print_times_init();
820 return pm_autosleep_init();
821}
822
823core_initcall(pm_init);