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 | ||
296699de RW |
34 | #ifdef CONFIG_SUSPEND |
35 | ||
36 | /* This is just an arbitrary number */ | |
37 | #define FREE_PAGE_NUMBER (100) | |
38 | ||
f242d919 | 39 | static struct platform_suspend_ops *suspend_ops; |
1da177e4 LT |
40 | |
41 | /** | |
26398a70 | 42 | * suspend_set_ops - Set the global suspend method table. |
1da177e4 LT |
43 | * @ops: Pointer to ops structure. |
44 | */ | |
45 | ||
26398a70 | 46 | void suspend_set_ops(struct platform_suspend_ops *ops) |
1da177e4 | 47 | { |
a6d70980 | 48 | mutex_lock(&pm_mutex); |
26398a70 | 49 | suspend_ops = ops; |
a6d70980 | 50 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
51 | } |
52 | ||
e8c9c502 | 53 | /** |
26398a70 | 54 | * suspend_valid_only_mem - generic memory-only valid callback |
e8c9c502 | 55 | * |
26398a70 | 56 | * Platform drivers that implement mem suspend only and only need |
e8c9c502 JB |
57 | * to check for that in their .valid callback can use this instead |
58 | * of rolling their own .valid callback. | |
59 | */ | |
26398a70 | 60 | int suspend_valid_only_mem(suspend_state_t state) |
e8c9c502 JB |
61 | { |
62 | return state == PM_SUSPEND_MEM; | |
63 | } | |
64 | ||
1da177e4 LT |
65 | /** |
66 | * suspend_prepare - Do prep work before entering low-power state. | |
1da177e4 | 67 | * |
6c961dfb RW |
68 | * This is common code that is called for each state that we're entering. |
69 | * Run suspend notifiers, allocate a console and stop all processes. | |
1da177e4 | 70 | */ |
6c961dfb | 71 | static int suspend_prepare(void) |
1da177e4 | 72 | { |
e3920fb4 | 73 | int error; |
5ae947ec | 74 | unsigned int free_pages; |
1da177e4 | 75 | |
26398a70 | 76 | if (!suspend_ops || !suspend_ops->enter) |
1da177e4 LT |
77 | return -EPERM; |
78 | ||
b10d9117 RW |
79 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); |
80 | if (error) | |
81 | goto Finish; | |
82 | ||
1da177e4 LT |
83 | pm_prepare_console(); |
84 | ||
85 | if (freeze_processes()) { | |
86 | error = -EAGAIN; | |
87 | goto Thaw; | |
88 | } | |
89 | ||
6c961dfb RW |
90 | free_pages = global_page_state(NR_FREE_PAGES); |
91 | if (free_pages < FREE_PAGE_NUMBER) { | |
5ae947ec DSL |
92 | pr_debug("PM: free some memory\n"); |
93 | shrink_all_memory(FREE_PAGE_NUMBER - free_pages); | |
94 | if (nr_free_pages() < FREE_PAGE_NUMBER) { | |
95 | error = -ENOMEM; | |
96 | printk(KERN_ERR "PM: No enough memory\n"); | |
5ae947ec DSL |
97 | } |
98 | } | |
e3c7db62 RW |
99 | if (!error) |
100 | return 0; | |
101 | ||
1da177e4 LT |
102 | Thaw: |
103 | thaw_processes(); | |
104 | pm_restore_console(); | |
b10d9117 RW |
105 | Finish: |
106 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
1da177e4 LT |
107 | return error; |
108 | } | |
109 | ||
a53c46dc JB |
110 | /* default implementation */ |
111 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
112 | { | |
113 | local_irq_disable(); | |
114 | } | |
115 | ||
116 | /* default implementation */ | |
117 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
118 | { | |
119 | local_irq_enable(); | |
120 | } | |
1da177e4 | 121 | |
6c961dfb RW |
122 | /** |
123 | * suspend_enter - enter the desired system sleep state. | |
124 | * @state: state to enter | |
125 | * | |
126 | * This function should be called after devices have been suspended. | |
127 | */ | |
a065c86e | 128 | static int suspend_enter(suspend_state_t state) |
1da177e4 LT |
129 | { |
130 | int error = 0; | |
1da177e4 | 131 | |
a53c46dc JB |
132 | arch_suspend_disable_irqs(); |
133 | BUG_ON(!irqs_disabled()); | |
1da177e4 LT |
134 | |
135 | if ((error = device_power_down(PMSG_SUSPEND))) { | |
136 | printk(KERN_ERR "Some devices failed to power down\n"); | |
137 | goto Done; | |
138 | } | |
26398a70 | 139 | error = suspend_ops->enter(state); |
1da177e4 LT |
140 | device_power_up(); |
141 | Done: | |
a53c46dc JB |
142 | arch_suspend_enable_irqs(); |
143 | BUG_ON(irqs_disabled()); | |
1da177e4 LT |
144 | return error; |
145 | } | |
146 | ||
6c961dfb RW |
147 | /** |
148 | * suspend_devices_and_enter - suspend devices and enter the desired system sleep | |
149 | * state. | |
150 | * @state: state to enter | |
151 | */ | |
152 | int suspend_devices_and_enter(suspend_state_t state) | |
153 | { | |
154 | int error; | |
155 | ||
26398a70 | 156 | if (!suspend_ops) |
6c961dfb RW |
157 | return -ENOSYS; |
158 | ||
26398a70 RW |
159 | if (suspend_ops->set_target) { |
160 | error = suspend_ops->set_target(state); | |
6c961dfb RW |
161 | if (error) |
162 | return error; | |
163 | } | |
164 | suspend_console(); | |
165 | error = device_suspend(PMSG_SUSPEND); | |
166 | if (error) { | |
167 | printk(KERN_ERR "Some devices failed to suspend\n"); | |
168 | goto Resume_console; | |
169 | } | |
26398a70 | 170 | if (suspend_ops->prepare) { |
e6c5eb95 | 171 | error = suspend_ops->prepare(); |
6c961dfb RW |
172 | if (error) |
173 | goto Resume_devices; | |
174 | } | |
175 | error = disable_nonboot_cpus(); | |
176 | if (!error) | |
177 | suspend_enter(state); | |
178 | ||
179 | enable_nonboot_cpus(); | |
e6c5eb95 RW |
180 | if (suspend_ops->finish) |
181 | suspend_ops->finish(); | |
6c961dfb RW |
182 | Resume_devices: |
183 | device_resume(); | |
184 | Resume_console: | |
185 | resume_console(); | |
186 | return error; | |
187 | } | |
1da177e4 LT |
188 | |
189 | /** | |
190 | * suspend_finish - Do final work before exiting suspend sequence. | |
1da177e4 LT |
191 | * |
192 | * Call platform code to clean up, restart processes, and free the | |
193 | * console that we've allocated. This is not called for suspend-to-disk. | |
194 | */ | |
6c961dfb | 195 | static void suspend_finish(void) |
1da177e4 | 196 | { |
1da177e4 LT |
197 | thaw_processes(); |
198 | pm_restore_console(); | |
b10d9117 | 199 | pm_notifier_call_chain(PM_POST_SUSPEND); |
1da177e4 LT |
200 | } |
201 | ||
202 | ||
203 | ||
204 | ||
3b364b8d | 205 | static const char * const pm_states[PM_SUSPEND_MAX] = { |
1da177e4 LT |
206 | [PM_SUSPEND_STANDBY] = "standby", |
207 | [PM_SUSPEND_MEM] = "mem", | |
1da177e4 LT |
208 | }; |
209 | ||
123d3c13 PM |
210 | static inline int valid_state(suspend_state_t state) |
211 | { | |
a3d25c27 RW |
212 | /* All states need lowlevel support and need to be valid |
213 | * to the lowlevel implementation, no valid callback | |
9684e51c | 214 | * implies that none are valid. */ |
26398a70 | 215 | if (!suspend_ops || !suspend_ops->valid || !suspend_ops->valid(state)) |
123d3c13 PM |
216 | return 0; |
217 | return 1; | |
218 | } | |
219 | ||
1da177e4 LT |
220 | |
221 | /** | |
222 | * enter_state - Do common work of entering low-power state. | |
223 | * @state: pm_state structure for state we're entering. | |
224 | * | |
225 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
226 | * if someone has beat us to it, since we don't want anything weird to | |
227 | * happen when we wake up. | |
228 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
229 | * we've woken up). | |
230 | */ | |
1da177e4 LT |
231 | static int enter_state(suspend_state_t state) |
232 | { | |
233 | int error; | |
234 | ||
123d3c13 | 235 | if (!valid_state(state)) |
eb9289eb | 236 | return -ENODEV; |
232b1432 | 237 | |
a6d70980 | 238 | if (!mutex_trylock(&pm_mutex)) |
1da177e4 LT |
239 | return -EBUSY; |
240 | ||
232b1432 RW |
241 | printk("Syncing filesystems ... "); |
242 | sys_sync(); | |
243 | printk("done.\n"); | |
244 | ||
82428b62 | 245 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
6c961dfb | 246 | if ((error = suspend_prepare())) |
1da177e4 LT |
247 | goto Unlock; |
248 | ||
82428b62 | 249 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
6c961dfb | 250 | error = suspend_devices_and_enter(state); |
1da177e4 | 251 | |
82428b62 | 252 | pr_debug("PM: Finishing wakeup.\n"); |
6c961dfb | 253 | suspend_finish(); |
1da177e4 | 254 | Unlock: |
a6d70980 | 255 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
256 | return error; |
257 | } | |
258 | ||
1da177e4 LT |
259 | |
260 | /** | |
261 | * pm_suspend - Externally visible function for suspending system. | |
a3d25c27 | 262 | * @state: Enumerated value of state to enter. |
1da177e4 LT |
263 | * |
264 | * Determine whether or not value is within range, get state | |
265 | * structure, and enter (above). | |
266 | */ | |
267 | ||
268 | int pm_suspend(suspend_state_t state) | |
269 | { | |
e2a5b420 | 270 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
1da177e4 LT |
271 | return enter_state(state); |
272 | return -EINVAL; | |
273 | } | |
274 | ||
4cf30348 | 275 | EXPORT_SYMBOL(pm_suspend); |
1da177e4 | 276 | |
296699de RW |
277 | #endif /* CONFIG_SUSPEND */ |
278 | ||
3514faca | 279 | decl_subsys(power, NULL); |
1da177e4 LT |
280 | |
281 | ||
282 | /** | |
283 | * state - control system power state. | |
284 | * | |
285 | * show() returns what states are supported, which is hard-coded to | |
286 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and | |
287 | * 'disk' (Suspend-to-Disk). | |
288 | * | |
289 | * store() accepts one of those strings, translates it into the | |
290 | * proper enumerated value, and initiates a suspend transition. | |
291 | */ | |
292 | ||
823bccfc | 293 | static ssize_t state_show(struct kset *kset, char *buf) |
1da177e4 | 294 | { |
296699de RW |
295 | char *s = buf; |
296 | #ifdef CONFIG_SUSPEND | |
1da177e4 | 297 | int i; |
1da177e4 LT |
298 | |
299 | for (i = 0; i < PM_SUSPEND_MAX; i++) { | |
123d3c13 PM |
300 | if (pm_states[i] && valid_state(i)) |
301 | s += sprintf(s,"%s ", pm_states[i]); | |
1da177e4 | 302 | } |
296699de | 303 | #endif |
b0cb1a19 | 304 | #ifdef CONFIG_HIBERNATION |
a3d25c27 RW |
305 | s += sprintf(s, "%s\n", "disk"); |
306 | #else | |
307 | if (s != buf) | |
308 | /* convert the last space to a newline */ | |
309 | *(s-1) = '\n'; | |
310 | #endif | |
1da177e4 LT |
311 | return (s - buf); |
312 | } | |
313 | ||
823bccfc | 314 | static ssize_t state_store(struct kset *kset, const char *buf, size_t n) |
1da177e4 | 315 | { |
296699de | 316 | #ifdef CONFIG_SUSPEND |
1da177e4 | 317 | suspend_state_t state = PM_SUSPEND_STANDBY; |
3b364b8d | 318 | const char * const *s; |
296699de | 319 | #endif |
1da177e4 | 320 | char *p; |
1da177e4 | 321 | int len; |
296699de | 322 | int error = -EINVAL; |
1da177e4 LT |
323 | |
324 | p = memchr(buf, '\n', n); | |
325 | len = p ? p - buf : n; | |
326 | ||
a3d25c27 | 327 | /* First, check if we are requested to hibernate */ |
8d98a690 | 328 | if (len == 4 && !strncmp(buf, "disk", len)) { |
a3d25c27 | 329 | error = hibernate(); |
296699de | 330 | goto Exit; |
a3d25c27 RW |
331 | } |
332 | ||
296699de | 333 | #ifdef CONFIG_SUSPEND |
1da177e4 | 334 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
8d98a690 | 335 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) |
1da177e4 LT |
336 | break; |
337 | } | |
47bb7899 | 338 | if (state < PM_SUSPEND_MAX && *s) |
1da177e4 | 339 | error = enter_state(state); |
296699de RW |
340 | #endif |
341 | ||
342 | Exit: | |
1da177e4 LT |
343 | return error ? error : n; |
344 | } | |
345 | ||
346 | power_attr(state); | |
347 | ||
c5c6ba4e RW |
348 | #ifdef CONFIG_PM_TRACE |
349 | int pm_trace_enabled; | |
350 | ||
823bccfc | 351 | static ssize_t pm_trace_show(struct kset *kset, char *buf) |
c5c6ba4e RW |
352 | { |
353 | return sprintf(buf, "%d\n", pm_trace_enabled); | |
354 | } | |
355 | ||
356 | static ssize_t | |
823bccfc | 357 | pm_trace_store(struct kset *kset, const char *buf, size_t n) |
c5c6ba4e RW |
358 | { |
359 | int val; | |
360 | ||
361 | if (sscanf(buf, "%d", &val) == 1) { | |
362 | pm_trace_enabled = !!val; | |
363 | return n; | |
364 | } | |
365 | return -EINVAL; | |
366 | } | |
367 | ||
368 | power_attr(pm_trace); | |
369 | ||
370 | static struct attribute * g[] = { | |
371 | &state_attr.attr, | |
372 | &pm_trace_attr.attr, | |
373 | NULL, | |
374 | }; | |
375 | #else | |
1da177e4 LT |
376 | static struct attribute * g[] = { |
377 | &state_attr.attr, | |
378 | NULL, | |
379 | }; | |
c5c6ba4e | 380 | #endif /* CONFIG_PM_TRACE */ |
1da177e4 LT |
381 | |
382 | static struct attribute_group attr_group = { | |
383 | .attrs = g, | |
384 | }; | |
385 | ||
386 | ||
387 | static int __init pm_init(void) | |
388 | { | |
389 | int error = subsystem_register(&power_subsys); | |
390 | if (!error) | |
823bccfc | 391 | error = sysfs_create_group(&power_subsys.kobj,&attr_group); |
1da177e4 LT |
392 | return error; |
393 | } | |
394 | ||
395 | core_initcall(pm_init); |