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 | ||
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 | |
296699de RW |
31 | #ifdef CONFIG_SUSPEND |
32 | ||
33 | /* This is just an arbitrary number */ | |
34 | #define FREE_PAGE_NUMBER (100) | |
35 | ||
f242d919 | 36 | static struct platform_suspend_ops *suspend_ops; |
1da177e4 LT |
37 | |
38 | /** | |
26398a70 | 39 | * suspend_set_ops - Set the global suspend method table. |
1da177e4 LT |
40 | * @ops: Pointer to ops structure. |
41 | */ | |
42 | ||
26398a70 | 43 | void suspend_set_ops(struct platform_suspend_ops *ops) |
1da177e4 | 44 | { |
a6d70980 | 45 | mutex_lock(&pm_mutex); |
26398a70 | 46 | suspend_ops = ops; |
a6d70980 | 47 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
48 | } |
49 | ||
e8c9c502 | 50 | /** |
26398a70 | 51 | * suspend_valid_only_mem - generic memory-only valid callback |
e8c9c502 | 52 | * |
26398a70 | 53 | * Platform drivers that implement mem suspend only and only need |
e8c9c502 JB |
54 | * to check for that in their .valid callback can use this instead |
55 | * of rolling their own .valid callback. | |
56 | */ | |
26398a70 | 57 | int suspend_valid_only_mem(suspend_state_t state) |
e8c9c502 JB |
58 | { |
59 | return state == PM_SUSPEND_MEM; | |
60 | } | |
61 | ||
1da177e4 LT |
62 | /** |
63 | * suspend_prepare - Do prep work before entering low-power state. | |
1da177e4 | 64 | * |
6c961dfb RW |
65 | * This is common code that is called for each state that we're entering. |
66 | * Run suspend notifiers, allocate a console and stop all processes. | |
1da177e4 | 67 | */ |
6c961dfb | 68 | static int suspend_prepare(void) |
1da177e4 | 69 | { |
e3920fb4 | 70 | int error; |
5ae947ec | 71 | unsigned int free_pages; |
1da177e4 | 72 | |
26398a70 | 73 | if (!suspend_ops || !suspend_ops->enter) |
1da177e4 LT |
74 | return -EPERM; |
75 | ||
b10d9117 RW |
76 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); |
77 | if (error) | |
78 | goto Finish; | |
79 | ||
1da177e4 LT |
80 | pm_prepare_console(); |
81 | ||
82 | if (freeze_processes()) { | |
83 | error = -EAGAIN; | |
84 | goto Thaw; | |
85 | } | |
86 | ||
6c961dfb RW |
87 | free_pages = global_page_state(NR_FREE_PAGES); |
88 | if (free_pages < FREE_PAGE_NUMBER) { | |
5ae947ec DSL |
89 | pr_debug("PM: free some memory\n"); |
90 | shrink_all_memory(FREE_PAGE_NUMBER - free_pages); | |
91 | if (nr_free_pages() < FREE_PAGE_NUMBER) { | |
92 | error = -ENOMEM; | |
93 | printk(KERN_ERR "PM: No enough memory\n"); | |
5ae947ec DSL |
94 | } |
95 | } | |
e3c7db62 RW |
96 | if (!error) |
97 | return 0; | |
98 | ||
1da177e4 LT |
99 | Thaw: |
100 | thaw_processes(); | |
101 | pm_restore_console(); | |
b10d9117 RW |
102 | Finish: |
103 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
1da177e4 LT |
104 | return error; |
105 | } | |
106 | ||
a53c46dc JB |
107 | /* default implementation */ |
108 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
109 | { | |
110 | local_irq_disable(); | |
111 | } | |
112 | ||
113 | /* default implementation */ | |
114 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
115 | { | |
116 | local_irq_enable(); | |
117 | } | |
1da177e4 | 118 | |
6c961dfb RW |
119 | /** |
120 | * suspend_enter - enter the desired system sleep state. | |
121 | * @state: state to enter | |
122 | * | |
123 | * This function should be called after devices have been suspended. | |
124 | */ | |
a065c86e | 125 | static int suspend_enter(suspend_state_t state) |
1da177e4 LT |
126 | { |
127 | int error = 0; | |
1da177e4 | 128 | |
a53c46dc JB |
129 | arch_suspend_disable_irqs(); |
130 | BUG_ON(!irqs_disabled()); | |
1da177e4 LT |
131 | |
132 | if ((error = device_power_down(PMSG_SUSPEND))) { | |
133 | printk(KERN_ERR "Some devices failed to power down\n"); | |
134 | goto Done; | |
135 | } | |
26398a70 | 136 | error = suspend_ops->enter(state); |
1da177e4 LT |
137 | device_power_up(); |
138 | Done: | |
a53c46dc JB |
139 | arch_suspend_enable_irqs(); |
140 | BUG_ON(irqs_disabled()); | |
1da177e4 LT |
141 | return error; |
142 | } | |
143 | ||
6c961dfb RW |
144 | /** |
145 | * suspend_devices_and_enter - suspend devices and enter the desired system sleep | |
146 | * state. | |
147 | * @state: state to enter | |
148 | */ | |
149 | int suspend_devices_and_enter(suspend_state_t state) | |
150 | { | |
151 | int error; | |
152 | ||
26398a70 | 153 | if (!suspend_ops) |
6c961dfb RW |
154 | return -ENOSYS; |
155 | ||
26398a70 RW |
156 | if (suspend_ops->set_target) { |
157 | error = suspend_ops->set_target(state); | |
6c961dfb RW |
158 | if (error) |
159 | return error; | |
160 | } | |
161 | suspend_console(); | |
162 | error = device_suspend(PMSG_SUSPEND); | |
163 | if (error) { | |
164 | printk(KERN_ERR "Some devices failed to suspend\n"); | |
165 | goto Resume_console; | |
166 | } | |
26398a70 | 167 | if (suspend_ops->prepare) { |
e6c5eb95 | 168 | error = suspend_ops->prepare(); |
6c961dfb RW |
169 | if (error) |
170 | goto Resume_devices; | |
171 | } | |
172 | error = disable_nonboot_cpus(); | |
173 | if (!error) | |
174 | suspend_enter(state); | |
175 | ||
176 | enable_nonboot_cpus(); | |
e6c5eb95 RW |
177 | if (suspend_ops->finish) |
178 | suspend_ops->finish(); | |
6c961dfb RW |
179 | Resume_devices: |
180 | device_resume(); | |
181 | Resume_console: | |
182 | resume_console(); | |
183 | return error; | |
184 | } | |
1da177e4 LT |
185 | |
186 | /** | |
187 | * suspend_finish - Do final work before exiting suspend sequence. | |
1da177e4 LT |
188 | * |
189 | * Call platform code to clean up, restart processes, and free the | |
190 | * console that we've allocated. This is not called for suspend-to-disk. | |
191 | */ | |
6c961dfb | 192 | static void suspend_finish(void) |
1da177e4 | 193 | { |
1da177e4 LT |
194 | thaw_processes(); |
195 | pm_restore_console(); | |
b10d9117 | 196 | pm_notifier_call_chain(PM_POST_SUSPEND); |
1da177e4 LT |
197 | } |
198 | ||
199 | ||
200 | ||
201 | ||
3b364b8d | 202 | static const char * const pm_states[PM_SUSPEND_MAX] = { |
1da177e4 LT |
203 | [PM_SUSPEND_STANDBY] = "standby", |
204 | [PM_SUSPEND_MEM] = "mem", | |
1da177e4 LT |
205 | }; |
206 | ||
123d3c13 PM |
207 | static inline int valid_state(suspend_state_t state) |
208 | { | |
a3d25c27 RW |
209 | /* All states need lowlevel support and need to be valid |
210 | * to the lowlevel implementation, no valid callback | |
9684e51c | 211 | * implies that none are valid. */ |
26398a70 | 212 | if (!suspend_ops || !suspend_ops->valid || !suspend_ops->valid(state)) |
123d3c13 PM |
213 | return 0; |
214 | return 1; | |
215 | } | |
216 | ||
1da177e4 LT |
217 | |
218 | /** | |
219 | * enter_state - Do common work of entering low-power state. | |
220 | * @state: pm_state structure for state we're entering. | |
221 | * | |
222 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
223 | * if someone has beat us to it, since we don't want anything weird to | |
224 | * happen when we wake up. | |
225 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
226 | * we've woken up). | |
227 | */ | |
1da177e4 LT |
228 | static int enter_state(suspend_state_t state) |
229 | { | |
230 | int error; | |
231 | ||
123d3c13 | 232 | if (!valid_state(state)) |
eb9289eb | 233 | return -ENODEV; |
232b1432 | 234 | |
a6d70980 | 235 | if (!mutex_trylock(&pm_mutex)) |
1da177e4 LT |
236 | return -EBUSY; |
237 | ||
232b1432 RW |
238 | printk("Syncing filesystems ... "); |
239 | sys_sync(); | |
240 | printk("done.\n"); | |
241 | ||
82428b62 | 242 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
6c961dfb | 243 | if ((error = suspend_prepare())) |
1da177e4 LT |
244 | goto Unlock; |
245 | ||
82428b62 | 246 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
6c961dfb | 247 | error = suspend_devices_and_enter(state); |
1da177e4 | 248 | |
82428b62 | 249 | pr_debug("PM: Finishing wakeup.\n"); |
6c961dfb | 250 | suspend_finish(); |
1da177e4 | 251 | Unlock: |
a6d70980 | 252 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
253 | return error; |
254 | } | |
255 | ||
1da177e4 LT |
256 | |
257 | /** | |
258 | * pm_suspend - Externally visible function for suspending system. | |
a3d25c27 | 259 | * @state: Enumerated value of state to enter. |
1da177e4 LT |
260 | * |
261 | * Determine whether or not value is within range, get state | |
262 | * structure, and enter (above). | |
263 | */ | |
264 | ||
265 | int pm_suspend(suspend_state_t state) | |
266 | { | |
e2a5b420 | 267 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
1da177e4 LT |
268 | return enter_state(state); |
269 | return -EINVAL; | |
270 | } | |
271 | ||
4cf30348 | 272 | EXPORT_SYMBOL(pm_suspend); |
1da177e4 | 273 | |
296699de RW |
274 | #endif /* CONFIG_SUSPEND */ |
275 | ||
1da177e4 LT |
276 | decl_subsys(power,NULL,NULL); |
277 | ||
278 | ||
279 | /** | |
280 | * state - control system power state. | |
281 | * | |
282 | * show() returns what states are supported, which is hard-coded to | |
283 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and | |
284 | * 'disk' (Suspend-to-Disk). | |
285 | * | |
286 | * store() accepts one of those strings, translates it into the | |
287 | * proper enumerated value, and initiates a suspend transition. | |
288 | */ | |
289 | ||
823bccfc | 290 | static ssize_t state_show(struct kset *kset, char *buf) |
1da177e4 | 291 | { |
296699de RW |
292 | char *s = buf; |
293 | #ifdef CONFIG_SUSPEND | |
1da177e4 | 294 | int i; |
1da177e4 LT |
295 | |
296 | for (i = 0; i < PM_SUSPEND_MAX; i++) { | |
123d3c13 PM |
297 | if (pm_states[i] && valid_state(i)) |
298 | s += sprintf(s,"%s ", pm_states[i]); | |
1da177e4 | 299 | } |
296699de | 300 | #endif |
b0cb1a19 | 301 | #ifdef CONFIG_HIBERNATION |
a3d25c27 RW |
302 | s += sprintf(s, "%s\n", "disk"); |
303 | #else | |
304 | if (s != buf) | |
305 | /* convert the last space to a newline */ | |
306 | *(s-1) = '\n'; | |
307 | #endif | |
1da177e4 LT |
308 | return (s - buf); |
309 | } | |
310 | ||
823bccfc | 311 | static ssize_t state_store(struct kset *kset, const char *buf, size_t n) |
1da177e4 | 312 | { |
296699de | 313 | #ifdef CONFIG_SUSPEND |
1da177e4 | 314 | suspend_state_t state = PM_SUSPEND_STANDBY; |
3b364b8d | 315 | const char * const *s; |
296699de | 316 | #endif |
1da177e4 | 317 | char *p; |
1da177e4 | 318 | int len; |
296699de | 319 | int error = -EINVAL; |
1da177e4 LT |
320 | |
321 | p = memchr(buf, '\n', n); | |
322 | len = p ? p - buf : n; | |
323 | ||
a3d25c27 | 324 | /* First, check if we are requested to hibernate */ |
8d98a690 | 325 | if (len == 4 && !strncmp(buf, "disk", len)) { |
a3d25c27 | 326 | error = hibernate(); |
296699de | 327 | goto Exit; |
a3d25c27 RW |
328 | } |
329 | ||
296699de | 330 | #ifdef CONFIG_SUSPEND |
1da177e4 | 331 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
8d98a690 | 332 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) |
1da177e4 LT |
333 | break; |
334 | } | |
47bb7899 | 335 | if (state < PM_SUSPEND_MAX && *s) |
1da177e4 | 336 | error = enter_state(state); |
296699de RW |
337 | #endif |
338 | ||
339 | Exit: | |
1da177e4 LT |
340 | return error ? error : n; |
341 | } | |
342 | ||
343 | power_attr(state); | |
344 | ||
c5c6ba4e RW |
345 | #ifdef CONFIG_PM_TRACE |
346 | int pm_trace_enabled; | |
347 | ||
823bccfc | 348 | static ssize_t pm_trace_show(struct kset *kset, char *buf) |
c5c6ba4e RW |
349 | { |
350 | return sprintf(buf, "%d\n", pm_trace_enabled); | |
351 | } | |
352 | ||
353 | static ssize_t | |
823bccfc | 354 | pm_trace_store(struct kset *kset, const char *buf, size_t n) |
c5c6ba4e RW |
355 | { |
356 | int val; | |
357 | ||
358 | if (sscanf(buf, "%d", &val) == 1) { | |
359 | pm_trace_enabled = !!val; | |
360 | return n; | |
361 | } | |
362 | return -EINVAL; | |
363 | } | |
364 | ||
365 | power_attr(pm_trace); | |
366 | ||
367 | static struct attribute * g[] = { | |
368 | &state_attr.attr, | |
369 | &pm_trace_attr.attr, | |
370 | NULL, | |
371 | }; | |
372 | #else | |
1da177e4 LT |
373 | static struct attribute * g[] = { |
374 | &state_attr.attr, | |
375 | NULL, | |
376 | }; | |
c5c6ba4e | 377 | #endif /* CONFIG_PM_TRACE */ |
1da177e4 LT |
378 | |
379 | static struct attribute_group attr_group = { | |
380 | .attrs = g, | |
381 | }; | |
382 | ||
383 | ||
384 | static int __init pm_init(void) | |
385 | { | |
386 | int error = subsystem_register(&power_subsys); | |
387 | if (!error) | |
823bccfc | 388 | error = sysfs_create_group(&power_subsys.kobj,&attr_group); |
1da177e4 LT |
389 | return error; |
390 | } | |
391 | ||
392 | core_initcall(pm_init); |