Commit | Line | Data |
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1da177e4 LT |
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 | ||
1da177e4 LT |
11 | #include <linux/kobject.h> |
12 | #include <linux/string.h> | |
c5c6ba4e | 13 | #include <linux/resume-trace.h> |
5e928f77 | 14 | #include <linux/workqueue.h> |
2a77c46d SL |
15 | #include <linux/debugfs.h> |
16 | #include <linux/seq_file.h> | |
1da177e4 LT |
17 | |
18 | #include "power.h" | |
19 | ||
a6d70980 | 20 | DEFINE_MUTEX(pm_mutex); |
1da177e4 | 21 | |
cd51e61c RW |
22 | #ifdef CONFIG_PM_SLEEP |
23 | ||
82525756 AS |
24 | /* Routines for PM-transition notifications */ |
25 | ||
26 | static BLOCKING_NOTIFIER_HEAD(pm_chain_head); | |
27 | ||
28 | int register_pm_notifier(struct notifier_block *nb) | |
29 | { | |
30 | return blocking_notifier_chain_register(&pm_chain_head, nb); | |
31 | } | |
32 | EXPORT_SYMBOL_GPL(register_pm_notifier); | |
33 | ||
34 | int unregister_pm_notifier(struct notifier_block *nb) | |
35 | { | |
36 | return blocking_notifier_chain_unregister(&pm_chain_head, nb); | |
37 | } | |
38 | EXPORT_SYMBOL_GPL(unregister_pm_notifier); | |
39 | ||
40 | int pm_notifier_call_chain(unsigned long val) | |
41 | { | |
f0c077a8 AM |
42 | int ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL); |
43 | ||
44 | return notifier_to_errno(ret); | |
82525756 AS |
45 | } |
46 | ||
0e06b4a8 RW |
47 | /* If set, devices may be suspended and resumed asynchronously. */ |
48 | int pm_async_enabled = 1; | |
49 | ||
50 | static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr, | |
51 | char *buf) | |
52 | { | |
53 | return sprintf(buf, "%d\n", pm_async_enabled); | |
54 | } | |
55 | ||
56 | static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr, | |
57 | const char *buf, size_t n) | |
58 | { | |
59 | unsigned long val; | |
60 | ||
61 | if (strict_strtoul(buf, 10, &val)) | |
62 | return -EINVAL; | |
63 | ||
64 | if (val > 1) | |
65 | return -EINVAL; | |
66 | ||
67 | pm_async_enabled = val; | |
68 | return n; | |
69 | } | |
70 | ||
71 | power_attr(pm_async); | |
72 | ||
0e7d56e3 RW |
73 | #ifdef CONFIG_PM_DEBUG |
74 | int pm_test_level = TEST_NONE; | |
75 | ||
0e7d56e3 RW |
76 | static const char * const pm_tests[__TEST_AFTER_LAST] = { |
77 | [TEST_NONE] = "none", | |
78 | [TEST_CORE] = "core", | |
79 | [TEST_CPUS] = "processors", | |
80 | [TEST_PLATFORM] = "platform", | |
81 | [TEST_DEVICES] = "devices", | |
82 | [TEST_FREEZER] = "freezer", | |
83 | }; | |
84 | ||
039a75c6 RW |
85 | static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr, |
86 | char *buf) | |
0e7d56e3 RW |
87 | { |
88 | char *s = buf; | |
89 | int level; | |
90 | ||
91 | for (level = TEST_FIRST; level <= TEST_MAX; level++) | |
92 | if (pm_tests[level]) { | |
93 | if (level == pm_test_level) | |
94 | s += sprintf(s, "[%s] ", pm_tests[level]); | |
95 | else | |
96 | s += sprintf(s, "%s ", pm_tests[level]); | |
97 | } | |
98 | ||
99 | if (s != buf) | |
100 | /* convert the last space to a newline */ | |
101 | *(s-1) = '\n'; | |
102 | ||
103 | return (s - buf); | |
104 | } | |
105 | ||
039a75c6 RW |
106 | static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, |
107 | const char *buf, size_t n) | |
0e7d56e3 RW |
108 | { |
109 | const char * const *s; | |
110 | int level; | |
111 | char *p; | |
112 | int len; | |
113 | int error = -EINVAL; | |
114 | ||
115 | p = memchr(buf, '\n', n); | |
116 | len = p ? p - buf : n; | |
117 | ||
118 | mutex_lock(&pm_mutex); | |
119 | ||
120 | level = TEST_FIRST; | |
121 | for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) | |
122 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) { | |
123 | pm_test_level = level; | |
124 | error = 0; | |
125 | break; | |
126 | } | |
127 | ||
128 | mutex_unlock(&pm_mutex); | |
129 | ||
130 | return error ? error : n; | |
131 | } | |
132 | ||
133 | power_attr(pm_test); | |
091d71e0 | 134 | #endif /* CONFIG_PM_DEBUG */ |
0e7d56e3 | 135 | |
7671b8ae | 136 | #endif /* CONFIG_PM_SLEEP */ |
039a75c6 | 137 | |
2a77c46d SL |
138 | #ifdef CONFIG_DEBUG_FS |
139 | static char *suspend_step_name(enum suspend_stat_step step) | |
140 | { | |
141 | switch (step) { | |
142 | case SUSPEND_FREEZE: | |
143 | return "freeze"; | |
144 | case SUSPEND_PREPARE: | |
145 | return "prepare"; | |
146 | case SUSPEND_SUSPEND: | |
147 | return "suspend"; | |
148 | case SUSPEND_SUSPEND_NOIRQ: | |
149 | return "suspend_noirq"; | |
150 | case SUSPEND_RESUME_NOIRQ: | |
151 | return "resume_noirq"; | |
152 | case SUSPEND_RESUME: | |
153 | return "resume"; | |
154 | default: | |
155 | return ""; | |
156 | } | |
157 | } | |
158 | ||
159 | static int suspend_stats_show(struct seq_file *s, void *unused) | |
160 | { | |
161 | int i, index, last_dev, last_errno, last_step; | |
162 | ||
163 | last_dev = suspend_stats.last_failed_dev + REC_FAILED_NUM - 1; | |
164 | last_dev %= REC_FAILED_NUM; | |
165 | last_errno = suspend_stats.last_failed_errno + REC_FAILED_NUM - 1; | |
166 | last_errno %= REC_FAILED_NUM; | |
167 | last_step = suspend_stats.last_failed_step + REC_FAILED_NUM - 1; | |
168 | last_step %= REC_FAILED_NUM; | |
169 | seq_printf(s, "%s: %d\n%s: %d\n%s: %d\n%s: %d\n" | |
170 | "%s: %d\n%s: %d\n%s: %d\n%s: %d\n", | |
171 | "success", suspend_stats.success, | |
172 | "fail", suspend_stats.fail, | |
173 | "failed_freeze", suspend_stats.failed_freeze, | |
174 | "failed_prepare", suspend_stats.failed_prepare, | |
175 | "failed_suspend", suspend_stats.failed_suspend, | |
176 | "failed_suspend_noirq", | |
177 | suspend_stats.failed_suspend_noirq, | |
178 | "failed_resume", suspend_stats.failed_resume, | |
179 | "failed_resume_noirq", | |
180 | suspend_stats.failed_resume_noirq); | |
181 | seq_printf(s, "failures:\n last_failed_dev:\t%-s\n", | |
182 | suspend_stats.failed_devs[last_dev]); | |
183 | for (i = 1; i < REC_FAILED_NUM; i++) { | |
184 | index = last_dev + REC_FAILED_NUM - i; | |
185 | index %= REC_FAILED_NUM; | |
186 | seq_printf(s, "\t\t\t%-s\n", | |
187 | suspend_stats.failed_devs[index]); | |
188 | } | |
189 | seq_printf(s, " last_failed_errno:\t%-d\n", | |
190 | suspend_stats.errno[last_errno]); | |
191 | for (i = 1; i < REC_FAILED_NUM; i++) { | |
192 | index = last_errno + REC_FAILED_NUM - i; | |
193 | index %= REC_FAILED_NUM; | |
194 | seq_printf(s, "\t\t\t%-d\n", | |
195 | suspend_stats.errno[index]); | |
196 | } | |
197 | seq_printf(s, " last_failed_step:\t%-s\n", | |
198 | suspend_step_name( | |
199 | suspend_stats.failed_steps[last_step])); | |
200 | for (i = 1; i < REC_FAILED_NUM; i++) { | |
201 | index = last_step + REC_FAILED_NUM - i; | |
202 | index %= REC_FAILED_NUM; | |
203 | seq_printf(s, "\t\t\t%-s\n", | |
204 | suspend_step_name( | |
205 | suspend_stats.failed_steps[index])); | |
206 | } | |
207 | ||
208 | return 0; | |
209 | } | |
210 | ||
211 | static int suspend_stats_open(struct inode *inode, struct file *file) | |
212 | { | |
213 | return single_open(file, suspend_stats_show, NULL); | |
214 | } | |
215 | ||
216 | static const struct file_operations suspend_stats_operations = { | |
217 | .open = suspend_stats_open, | |
218 | .read = seq_read, | |
219 | .llseek = seq_lseek, | |
220 | .release = single_release, | |
221 | }; | |
222 | ||
223 | static int __init pm_debugfs_init(void) | |
224 | { | |
225 | debugfs_create_file("suspend_stats", S_IFREG | S_IRUGO, | |
226 | NULL, NULL, &suspend_stats_operations); | |
227 | return 0; | |
228 | } | |
229 | ||
230 | late_initcall(pm_debugfs_init); | |
231 | #endif /* CONFIG_DEBUG_FS */ | |
232 | ||
d76e15fb | 233 | struct kobject *power_kobj; |
1da177e4 LT |
234 | |
235 | /** | |
236 | * state - control system power state. | |
237 | * | |
238 | * show() returns what states are supported, which is hard-coded to | |
239 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and | |
240 | * 'disk' (Suspend-to-Disk). | |
241 | * | |
242 | * store() accepts one of those strings, translates it into the | |
243 | * proper enumerated value, and initiates a suspend transition. | |
244 | */ | |
386f275f KS |
245 | static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, |
246 | char *buf) | |
1da177e4 | 247 | { |
296699de RW |
248 | char *s = buf; |
249 | #ifdef CONFIG_SUSPEND | |
1da177e4 | 250 | int i; |
1da177e4 LT |
251 | |
252 | for (i = 0; i < PM_SUSPEND_MAX; i++) { | |
123d3c13 PM |
253 | if (pm_states[i] && valid_state(i)) |
254 | s += sprintf(s,"%s ", pm_states[i]); | |
1da177e4 | 255 | } |
296699de | 256 | #endif |
b0cb1a19 | 257 | #ifdef CONFIG_HIBERNATION |
a3d25c27 RW |
258 | s += sprintf(s, "%s\n", "disk"); |
259 | #else | |
260 | if (s != buf) | |
261 | /* convert the last space to a newline */ | |
262 | *(s-1) = '\n'; | |
263 | #endif | |
1da177e4 LT |
264 | return (s - buf); |
265 | } | |
266 | ||
386f275f KS |
267 | static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, |
268 | const char *buf, size_t n) | |
1da177e4 | 269 | { |
296699de | 270 | #ifdef CONFIG_SUSPEND |
1da177e4 | 271 | suspend_state_t state = PM_SUSPEND_STANDBY; |
3b364b8d | 272 | const char * const *s; |
296699de | 273 | #endif |
1da177e4 | 274 | char *p; |
1da177e4 | 275 | int len; |
296699de | 276 | int error = -EINVAL; |
1da177e4 LT |
277 | |
278 | p = memchr(buf, '\n', n); | |
279 | len = p ? p - buf : n; | |
280 | ||
a3d25c27 | 281 | /* First, check if we are requested to hibernate */ |
8d98a690 | 282 | if (len == 4 && !strncmp(buf, "disk", len)) { |
a3d25c27 | 283 | error = hibernate(); |
296699de | 284 | goto Exit; |
a3d25c27 RW |
285 | } |
286 | ||
296699de | 287 | #ifdef CONFIG_SUSPEND |
1da177e4 | 288 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
8d98a690 | 289 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) |
1da177e4 LT |
290 | break; |
291 | } | |
47bb7899 | 292 | if (state < PM_SUSPEND_MAX && *s) |
1da177e4 | 293 | error = enter_state(state); |
2a77c46d SL |
294 | if (error) { |
295 | suspend_stats.fail++; | |
296 | dpm_save_failed_errno(error); | |
297 | } else | |
298 | suspend_stats.success++; | |
296699de RW |
299 | #endif |
300 | ||
301 | Exit: | |
1da177e4 LT |
302 | return error ? error : n; |
303 | } | |
304 | ||
305 | power_attr(state); | |
306 | ||
c125e96f RW |
307 | #ifdef CONFIG_PM_SLEEP |
308 | /* | |
309 | * The 'wakeup_count' attribute, along with the functions defined in | |
310 | * drivers/base/power/wakeup.c, provides a means by which wakeup events can be | |
311 | * handled in a non-racy way. | |
312 | * | |
313 | * If a wakeup event occurs when the system is in a sleep state, it simply is | |
314 | * woken up. In turn, if an event that would wake the system up from a sleep | |
315 | * state occurs when it is undergoing a transition to that sleep state, the | |
316 | * transition should be aborted. Moreover, if such an event occurs when the | |
317 | * system is in the working state, an attempt to start a transition to the | |
318 | * given sleep state should fail during certain period after the detection of | |
319 | * the event. Using the 'state' attribute alone is not sufficient to satisfy | |
320 | * these requirements, because a wakeup event may occur exactly when 'state' | |
321 | * is being written to and may be delivered to user space right before it is | |
322 | * frozen, so the event will remain only partially processed until the system is | |
323 | * woken up by another event. In particular, it won't cause the transition to | |
324 | * a sleep state to be aborted. | |
325 | * | |
326 | * This difficulty may be overcome if user space uses 'wakeup_count' before | |
327 | * writing to 'state'. It first should read from 'wakeup_count' and store | |
328 | * the read value. Then, after carrying out its own preparations for the system | |
329 | * transition to a sleep state, it should write the stored value to | |
25985edc | 330 | * 'wakeup_count'. If that fails, at least one wakeup event has occurred since |
c125e96f RW |
331 | * 'wakeup_count' was read and 'state' should not be written to. Otherwise, it |
332 | * is allowed to write to 'state', but the transition will be aborted if there | |
333 | * are any wakeup events detected after 'wakeup_count' was written to. | |
334 | */ | |
335 | ||
336 | static ssize_t wakeup_count_show(struct kobject *kobj, | |
337 | struct kobj_attribute *attr, | |
338 | char *buf) | |
339 | { | |
074037ec | 340 | unsigned int val; |
c125e96f | 341 | |
074037ec | 342 | return pm_get_wakeup_count(&val) ? sprintf(buf, "%u\n", val) : -EINTR; |
c125e96f RW |
343 | } |
344 | ||
345 | static ssize_t wakeup_count_store(struct kobject *kobj, | |
346 | struct kobj_attribute *attr, | |
347 | const char *buf, size_t n) | |
348 | { | |
074037ec | 349 | unsigned int val; |
c125e96f | 350 | |
074037ec | 351 | if (sscanf(buf, "%u", &val) == 1) { |
c125e96f RW |
352 | if (pm_save_wakeup_count(val)) |
353 | return n; | |
354 | } | |
355 | return -EINVAL; | |
356 | } | |
357 | ||
358 | power_attr(wakeup_count); | |
359 | #endif /* CONFIG_PM_SLEEP */ | |
360 | ||
c5c6ba4e RW |
361 | #ifdef CONFIG_PM_TRACE |
362 | int pm_trace_enabled; | |
363 | ||
386f275f KS |
364 | static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr, |
365 | char *buf) | |
c5c6ba4e RW |
366 | { |
367 | return sprintf(buf, "%d\n", pm_trace_enabled); | |
368 | } | |
369 | ||
370 | static ssize_t | |
386f275f KS |
371 | pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr, |
372 | const char *buf, size_t n) | |
c5c6ba4e RW |
373 | { |
374 | int val; | |
375 | ||
376 | if (sscanf(buf, "%d", &val) == 1) { | |
377 | pm_trace_enabled = !!val; | |
378 | return n; | |
379 | } | |
380 | return -EINVAL; | |
381 | } | |
382 | ||
383 | power_attr(pm_trace); | |
d33ac60b JH |
384 | |
385 | static ssize_t pm_trace_dev_match_show(struct kobject *kobj, | |
386 | struct kobj_attribute *attr, | |
387 | char *buf) | |
388 | { | |
389 | return show_trace_dev_match(buf, PAGE_SIZE); | |
390 | } | |
391 | ||
392 | static ssize_t | |
393 | pm_trace_dev_match_store(struct kobject *kobj, struct kobj_attribute *attr, | |
394 | const char *buf, size_t n) | |
395 | { | |
396 | return -EINVAL; | |
397 | } | |
398 | ||
399 | power_attr(pm_trace_dev_match); | |
400 | ||
0e7d56e3 | 401 | #endif /* CONFIG_PM_TRACE */ |
c5c6ba4e RW |
402 | |
403 | static struct attribute * g[] = { | |
404 | &state_attr.attr, | |
0e7d56e3 | 405 | #ifdef CONFIG_PM_TRACE |
c5c6ba4e | 406 | &pm_trace_attr.attr, |
d33ac60b | 407 | &pm_trace_dev_match_attr.attr, |
0e7d56e3 | 408 | #endif |
0e06b4a8 RW |
409 | #ifdef CONFIG_PM_SLEEP |
410 | &pm_async_attr.attr, | |
c125e96f | 411 | &wakeup_count_attr.attr, |
0e06b4a8 | 412 | #ifdef CONFIG_PM_DEBUG |
0e7d56e3 | 413 | &pm_test_attr.attr, |
0e06b4a8 | 414 | #endif |
0e7d56e3 | 415 | #endif |
c5c6ba4e RW |
416 | NULL, |
417 | }; | |
1da177e4 LT |
418 | |
419 | static struct attribute_group attr_group = { | |
420 | .attrs = g, | |
421 | }; | |
422 | ||
5e928f77 RW |
423 | #ifdef CONFIG_PM_RUNTIME |
424 | struct workqueue_struct *pm_wq; | |
7b199ca2 | 425 | EXPORT_SYMBOL_GPL(pm_wq); |
5e928f77 RW |
426 | |
427 | static int __init pm_start_workqueue(void) | |
428 | { | |
58a69cb4 | 429 | pm_wq = alloc_workqueue("pm", WQ_FREEZABLE, 0); |
5e928f77 RW |
430 | |
431 | return pm_wq ? 0 : -ENOMEM; | |
432 | } | |
433 | #else | |
434 | static inline int pm_start_workqueue(void) { return 0; } | |
435 | #endif | |
436 | ||
1da177e4 LT |
437 | static int __init pm_init(void) |
438 | { | |
5e928f77 RW |
439 | int error = pm_start_workqueue(); |
440 | if (error) | |
441 | return error; | |
ac5c24ec | 442 | hibernate_image_size_init(); |
ddeb6487 | 443 | hibernate_reserved_size_init(); |
d76e15fb GKH |
444 | power_kobj = kobject_create_and_add("power", NULL); |
445 | if (!power_kobj) | |
039a5dcd | 446 | return -ENOMEM; |
d76e15fb | 447 | return sysfs_create_group(power_kobj, &attr_group); |
1da177e4 LT |
448 | } |
449 | ||
450 | core_initcall(pm_init); |