Commit | Line | Data |
---|---|---|
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 | ||
4cf30348 | 11 | #include <linux/module.h> |
1da177e4 LT |
12 | #include <linux/suspend.h> |
13 | #include <linux/kobject.h> | |
14 | #include <linux/string.h> | |
15 | #include <linux/delay.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/init.h> | |
6cc07191 | 18 | #include <linux/console.h> |
e3920fb4 | 19 | #include <linux/cpu.h> |
c5c6ba4e | 20 | #include <linux/resume-trace.h> |
7dfb7103 | 21 | #include <linux/freezer.h> |
96177299 | 22 | #include <linux/vmstat.h> |
232b1432 | 23 | #include <linux/syscalls.h> |
1da177e4 LT |
24 | |
25 | #include "power.h" | |
26 | ||
b10d9117 RW |
27 | BLOCKING_NOTIFIER_HEAD(pm_chain_head); |
28 | ||
a6d70980 | 29 | DEFINE_MUTEX(pm_mutex); |
1da177e4 | 30 | |
9f9adecd LB |
31 | unsigned int pm_flags; |
32 | EXPORT_SYMBOL(pm_flags); | |
33 | ||
0e7d56e3 RW |
34 | #ifdef CONFIG_PM_DEBUG |
35 | int pm_test_level = TEST_NONE; | |
36 | ||
37 | static int suspend_test(int level) | |
38 | { | |
39 | if (pm_test_level == level) { | |
40 | printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); | |
41 | mdelay(5000); | |
42 | return 1; | |
43 | } | |
44 | return 0; | |
45 | } | |
46 | ||
47 | static const char * const pm_tests[__TEST_AFTER_LAST] = { | |
48 | [TEST_NONE] = "none", | |
49 | [TEST_CORE] = "core", | |
50 | [TEST_CPUS] = "processors", | |
51 | [TEST_PLATFORM] = "platform", | |
52 | [TEST_DEVICES] = "devices", | |
53 | [TEST_FREEZER] = "freezer", | |
54 | }; | |
55 | ||
039a75c6 RW |
56 | static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr, |
57 | char *buf) | |
0e7d56e3 RW |
58 | { |
59 | char *s = buf; | |
60 | int level; | |
61 | ||
62 | for (level = TEST_FIRST; level <= TEST_MAX; level++) | |
63 | if (pm_tests[level]) { | |
64 | if (level == pm_test_level) | |
65 | s += sprintf(s, "[%s] ", pm_tests[level]); | |
66 | else | |
67 | s += sprintf(s, "%s ", pm_tests[level]); | |
68 | } | |
69 | ||
70 | if (s != buf) | |
71 | /* convert the last space to a newline */ | |
72 | *(s-1) = '\n'; | |
73 | ||
74 | return (s - buf); | |
75 | } | |
76 | ||
039a75c6 RW |
77 | static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, |
78 | const char *buf, size_t n) | |
0e7d56e3 RW |
79 | { |
80 | const char * const *s; | |
81 | int level; | |
82 | char *p; | |
83 | int len; | |
84 | int error = -EINVAL; | |
85 | ||
86 | p = memchr(buf, '\n', n); | |
87 | len = p ? p - buf : n; | |
88 | ||
89 | mutex_lock(&pm_mutex); | |
90 | ||
91 | level = TEST_FIRST; | |
92 | for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) | |
93 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) { | |
94 | pm_test_level = level; | |
95 | error = 0; | |
96 | break; | |
97 | } | |
98 | ||
99 | mutex_unlock(&pm_mutex); | |
100 | ||
101 | return error ? error : n; | |
102 | } | |
103 | ||
104 | power_attr(pm_test); | |
105 | #else /* !CONFIG_PM_DEBUG */ | |
106 | static inline int suspend_test(int level) { return 0; } | |
107 | #endif /* !CONFIG_PM_DEBUG */ | |
108 | ||
039a75c6 | 109 | |
296699de RW |
110 | #ifdef CONFIG_SUSPEND |
111 | ||
112 | /* This is just an arbitrary number */ | |
113 | #define FREE_PAGE_NUMBER (100) | |
114 | ||
f242d919 | 115 | static struct platform_suspend_ops *suspend_ops; |
1da177e4 LT |
116 | |
117 | /** | |
26398a70 | 118 | * suspend_set_ops - Set the global suspend method table. |
1da177e4 LT |
119 | * @ops: Pointer to ops structure. |
120 | */ | |
121 | ||
26398a70 | 122 | void suspend_set_ops(struct platform_suspend_ops *ops) |
1da177e4 | 123 | { |
a6d70980 | 124 | mutex_lock(&pm_mutex); |
26398a70 | 125 | suspend_ops = ops; |
a6d70980 | 126 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
127 | } |
128 | ||
e8c9c502 | 129 | /** |
26398a70 | 130 | * suspend_valid_only_mem - generic memory-only valid callback |
e8c9c502 | 131 | * |
26398a70 | 132 | * Platform drivers that implement mem suspend only and only need |
e8c9c502 JB |
133 | * to check for that in their .valid callback can use this instead |
134 | * of rolling their own .valid callback. | |
135 | */ | |
26398a70 | 136 | int suspend_valid_only_mem(suspend_state_t state) |
e8c9c502 JB |
137 | { |
138 | return state == PM_SUSPEND_MEM; | |
139 | } | |
140 | ||
1da177e4 LT |
141 | /** |
142 | * suspend_prepare - Do prep work before entering low-power state. | |
1da177e4 | 143 | * |
6c961dfb RW |
144 | * This is common code that is called for each state that we're entering. |
145 | * Run suspend notifiers, allocate a console and stop all processes. | |
1da177e4 | 146 | */ |
6c961dfb | 147 | static int suspend_prepare(void) |
1da177e4 | 148 | { |
e3920fb4 | 149 | int error; |
5ae947ec | 150 | unsigned int free_pages; |
1da177e4 | 151 | |
26398a70 | 152 | if (!suspend_ops || !suspend_ops->enter) |
1da177e4 LT |
153 | return -EPERM; |
154 | ||
b10d9117 RW |
155 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); |
156 | if (error) | |
157 | goto Finish; | |
158 | ||
1da177e4 LT |
159 | pm_prepare_console(); |
160 | ||
161 | if (freeze_processes()) { | |
162 | error = -EAGAIN; | |
163 | goto Thaw; | |
164 | } | |
165 | ||
6c961dfb RW |
166 | free_pages = global_page_state(NR_FREE_PAGES); |
167 | if (free_pages < FREE_PAGE_NUMBER) { | |
5ae947ec DSL |
168 | pr_debug("PM: free some memory\n"); |
169 | shrink_all_memory(FREE_PAGE_NUMBER - free_pages); | |
170 | if (nr_free_pages() < FREE_PAGE_NUMBER) { | |
171 | error = -ENOMEM; | |
172 | printk(KERN_ERR "PM: No enough memory\n"); | |
5ae947ec DSL |
173 | } |
174 | } | |
e3c7db62 RW |
175 | if (!error) |
176 | return 0; | |
177 | ||
1da177e4 LT |
178 | Thaw: |
179 | thaw_processes(); | |
180 | pm_restore_console(); | |
b10d9117 RW |
181 | Finish: |
182 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
1da177e4 LT |
183 | return error; |
184 | } | |
185 | ||
a53c46dc JB |
186 | /* default implementation */ |
187 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
188 | { | |
189 | local_irq_disable(); | |
190 | } | |
191 | ||
192 | /* default implementation */ | |
193 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
194 | { | |
195 | local_irq_enable(); | |
196 | } | |
1da177e4 | 197 | |
6c961dfb RW |
198 | /** |
199 | * suspend_enter - enter the desired system sleep state. | |
200 | * @state: state to enter | |
201 | * | |
202 | * This function should be called after devices have been suspended. | |
203 | */ | |
a065c86e | 204 | static int suspend_enter(suspend_state_t state) |
1da177e4 LT |
205 | { |
206 | int error = 0; | |
1da177e4 | 207 | |
a53c46dc JB |
208 | arch_suspend_disable_irqs(); |
209 | BUG_ON(!irqs_disabled()); | |
1da177e4 LT |
210 | |
211 | if ((error = device_power_down(PMSG_SUSPEND))) { | |
212 | printk(KERN_ERR "Some devices failed to power down\n"); | |
213 | goto Done; | |
214 | } | |
0e7d56e3 RW |
215 | |
216 | if (!suspend_test(TEST_CORE)) | |
217 | error = suspend_ops->enter(state); | |
218 | ||
1da177e4 LT |
219 | device_power_up(); |
220 | Done: | |
a53c46dc JB |
221 | arch_suspend_enable_irqs(); |
222 | BUG_ON(irqs_disabled()); | |
1da177e4 LT |
223 | return error; |
224 | } | |
225 | ||
6c961dfb RW |
226 | /** |
227 | * suspend_devices_and_enter - suspend devices and enter the desired system sleep | |
228 | * state. | |
229 | * @state: state to enter | |
230 | */ | |
231 | int suspend_devices_and_enter(suspend_state_t state) | |
232 | { | |
233 | int error; | |
234 | ||
26398a70 | 235 | if (!suspend_ops) |
6c961dfb RW |
236 | return -ENOSYS; |
237 | ||
26398a70 RW |
238 | if (suspend_ops->set_target) { |
239 | error = suspend_ops->set_target(state); | |
6c961dfb RW |
240 | if (error) |
241 | return error; | |
242 | } | |
243 | suspend_console(); | |
244 | error = device_suspend(PMSG_SUSPEND); | |
245 | if (error) { | |
246 | printk(KERN_ERR "Some devices failed to suspend\n"); | |
247 | goto Resume_console; | |
248 | } | |
0e7d56e3 RW |
249 | |
250 | if (suspend_test(TEST_DEVICES)) | |
251 | goto Resume_devices; | |
252 | ||
26398a70 | 253 | if (suspend_ops->prepare) { |
e6c5eb95 | 254 | error = suspend_ops->prepare(); |
6c961dfb RW |
255 | if (error) |
256 | goto Resume_devices; | |
257 | } | |
0e7d56e3 RW |
258 | |
259 | if (suspend_test(TEST_PLATFORM)) | |
260 | goto Finish; | |
261 | ||
6c961dfb | 262 | error = disable_nonboot_cpus(); |
0e7d56e3 | 263 | if (!error && !suspend_test(TEST_CPUS)) |
6c961dfb RW |
264 | suspend_enter(state); |
265 | ||
266 | enable_nonboot_cpus(); | |
0e7d56e3 | 267 | Finish: |
e6c5eb95 RW |
268 | if (suspend_ops->finish) |
269 | suspend_ops->finish(); | |
6c961dfb RW |
270 | Resume_devices: |
271 | device_resume(); | |
272 | Resume_console: | |
273 | resume_console(); | |
274 | return error; | |
275 | } | |
1da177e4 LT |
276 | |
277 | /** | |
278 | * suspend_finish - Do final work before exiting suspend sequence. | |
1da177e4 LT |
279 | * |
280 | * Call platform code to clean up, restart processes, and free the | |
281 | * console that we've allocated. This is not called for suspend-to-disk. | |
282 | */ | |
6c961dfb | 283 | static void suspend_finish(void) |
1da177e4 | 284 | { |
1da177e4 LT |
285 | thaw_processes(); |
286 | pm_restore_console(); | |
b10d9117 | 287 | pm_notifier_call_chain(PM_POST_SUSPEND); |
1da177e4 LT |
288 | } |
289 | ||
290 | ||
291 | ||
292 | ||
3b364b8d | 293 | static const char * const pm_states[PM_SUSPEND_MAX] = { |
1da177e4 LT |
294 | [PM_SUSPEND_STANDBY] = "standby", |
295 | [PM_SUSPEND_MEM] = "mem", | |
1da177e4 LT |
296 | }; |
297 | ||
123d3c13 PM |
298 | static inline int valid_state(suspend_state_t state) |
299 | { | |
a3d25c27 RW |
300 | /* All states need lowlevel support and need to be valid |
301 | * to the lowlevel implementation, no valid callback | |
9684e51c | 302 | * implies that none are valid. */ |
26398a70 | 303 | if (!suspend_ops || !suspend_ops->valid || !suspend_ops->valid(state)) |
123d3c13 PM |
304 | return 0; |
305 | return 1; | |
306 | } | |
307 | ||
1da177e4 LT |
308 | |
309 | /** | |
310 | * enter_state - Do common work of entering low-power state. | |
311 | * @state: pm_state structure for state we're entering. | |
312 | * | |
313 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
314 | * if someone has beat us to it, since we don't want anything weird to | |
315 | * happen when we wake up. | |
316 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
317 | * we've woken up). | |
318 | */ | |
1da177e4 LT |
319 | static int enter_state(suspend_state_t state) |
320 | { | |
321 | int error; | |
322 | ||
123d3c13 | 323 | if (!valid_state(state)) |
eb9289eb | 324 | return -ENODEV; |
232b1432 | 325 | |
a6d70980 | 326 | if (!mutex_trylock(&pm_mutex)) |
1da177e4 LT |
327 | return -EBUSY; |
328 | ||
232b1432 RW |
329 | printk("Syncing filesystems ... "); |
330 | sys_sync(); | |
331 | printk("done.\n"); | |
332 | ||
82428b62 | 333 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
0e7d56e3 RW |
334 | error = suspend_prepare(); |
335 | if (error) | |
1da177e4 LT |
336 | goto Unlock; |
337 | ||
0e7d56e3 RW |
338 | if (suspend_test(TEST_FREEZER)) |
339 | goto Finish; | |
340 | ||
82428b62 | 341 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
6c961dfb | 342 | error = suspend_devices_and_enter(state); |
1da177e4 | 343 | |
0e7d56e3 | 344 | Finish: |
82428b62 | 345 | pr_debug("PM: Finishing wakeup.\n"); |
6c961dfb | 346 | suspend_finish(); |
1da177e4 | 347 | Unlock: |
a6d70980 | 348 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
349 | return error; |
350 | } | |
351 | ||
1da177e4 LT |
352 | |
353 | /** | |
354 | * pm_suspend - Externally visible function for suspending system. | |
a3d25c27 | 355 | * @state: Enumerated value of state to enter. |
1da177e4 LT |
356 | * |
357 | * Determine whether or not value is within range, get state | |
358 | * structure, and enter (above). | |
359 | */ | |
360 | ||
361 | int pm_suspend(suspend_state_t state) | |
362 | { | |
e2a5b420 | 363 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
1da177e4 LT |
364 | return enter_state(state); |
365 | return -EINVAL; | |
366 | } | |
367 | ||
4cf30348 | 368 | EXPORT_SYMBOL(pm_suspend); |
1da177e4 | 369 | |
296699de RW |
370 | #endif /* CONFIG_SUSPEND */ |
371 | ||
d76e15fb | 372 | struct kobject *power_kobj; |
1da177e4 LT |
373 | |
374 | /** | |
375 | * state - control system power state. | |
376 | * | |
377 | * show() returns what states are supported, which is hard-coded to | |
378 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and | |
379 | * 'disk' (Suspend-to-Disk). | |
380 | * | |
381 | * store() accepts one of those strings, translates it into the | |
382 | * proper enumerated value, and initiates a suspend transition. | |
383 | */ | |
384 | ||
386f275f KS |
385 | static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, |
386 | char *buf) | |
1da177e4 | 387 | { |
296699de RW |
388 | char *s = buf; |
389 | #ifdef CONFIG_SUSPEND | |
1da177e4 | 390 | int i; |
1da177e4 LT |
391 | |
392 | for (i = 0; i < PM_SUSPEND_MAX; i++) { | |
123d3c13 PM |
393 | if (pm_states[i] && valid_state(i)) |
394 | s += sprintf(s,"%s ", pm_states[i]); | |
1da177e4 | 395 | } |
296699de | 396 | #endif |
b0cb1a19 | 397 | #ifdef CONFIG_HIBERNATION |
a3d25c27 RW |
398 | s += sprintf(s, "%s\n", "disk"); |
399 | #else | |
400 | if (s != buf) | |
401 | /* convert the last space to a newline */ | |
402 | *(s-1) = '\n'; | |
403 | #endif | |
1da177e4 LT |
404 | return (s - buf); |
405 | } | |
406 | ||
386f275f KS |
407 | static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, |
408 | const char *buf, size_t n) | |
1da177e4 | 409 | { |
296699de | 410 | #ifdef CONFIG_SUSPEND |
1da177e4 | 411 | suspend_state_t state = PM_SUSPEND_STANDBY; |
3b364b8d | 412 | const char * const *s; |
296699de | 413 | #endif |
1da177e4 | 414 | char *p; |
1da177e4 | 415 | int len; |
296699de | 416 | int error = -EINVAL; |
1da177e4 LT |
417 | |
418 | p = memchr(buf, '\n', n); | |
419 | len = p ? p - buf : n; | |
420 | ||
a3d25c27 | 421 | /* First, check if we are requested to hibernate */ |
8d98a690 | 422 | if (len == 4 && !strncmp(buf, "disk", len)) { |
a3d25c27 | 423 | error = hibernate(); |
296699de | 424 | goto Exit; |
a3d25c27 RW |
425 | } |
426 | ||
296699de | 427 | #ifdef CONFIG_SUSPEND |
1da177e4 | 428 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
8d98a690 | 429 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) |
1da177e4 LT |
430 | break; |
431 | } | |
47bb7899 | 432 | if (state < PM_SUSPEND_MAX && *s) |
1da177e4 | 433 | error = enter_state(state); |
296699de RW |
434 | #endif |
435 | ||
436 | Exit: | |
1da177e4 LT |
437 | return error ? error : n; |
438 | } | |
439 | ||
440 | power_attr(state); | |
441 | ||
c5c6ba4e RW |
442 | #ifdef CONFIG_PM_TRACE |
443 | int pm_trace_enabled; | |
444 | ||
386f275f KS |
445 | static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr, |
446 | char *buf) | |
c5c6ba4e RW |
447 | { |
448 | return sprintf(buf, "%d\n", pm_trace_enabled); | |
449 | } | |
450 | ||
451 | static ssize_t | |
386f275f KS |
452 | pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr, |
453 | const char *buf, size_t n) | |
c5c6ba4e RW |
454 | { |
455 | int val; | |
456 | ||
457 | if (sscanf(buf, "%d", &val) == 1) { | |
458 | pm_trace_enabled = !!val; | |
459 | return n; | |
460 | } | |
461 | return -EINVAL; | |
462 | } | |
463 | ||
464 | power_attr(pm_trace); | |
0e7d56e3 | 465 | #endif /* CONFIG_PM_TRACE */ |
c5c6ba4e RW |
466 | |
467 | static struct attribute * g[] = { | |
468 | &state_attr.attr, | |
0e7d56e3 | 469 | #ifdef CONFIG_PM_TRACE |
c5c6ba4e | 470 | &pm_trace_attr.attr, |
0e7d56e3 RW |
471 | #endif |
472 | #ifdef CONFIG_PM_DEBUG | |
473 | &pm_test_attr.attr, | |
474 | #endif | |
c5c6ba4e RW |
475 | NULL, |
476 | }; | |
1da177e4 LT |
477 | |
478 | static struct attribute_group attr_group = { | |
479 | .attrs = g, | |
480 | }; | |
481 | ||
482 | ||
483 | static int __init pm_init(void) | |
484 | { | |
d76e15fb GKH |
485 | power_kobj = kobject_create_and_add("power", NULL); |
486 | if (!power_kobj) | |
039a5dcd | 487 | return -ENOMEM; |
d76e15fb | 488 | return sysfs_create_group(power_kobj, &attr_group); |
1da177e4 LT |
489 | } |
490 | ||
491 | core_initcall(pm_init); |