Commit | Line | Data |
---|---|---|
a9d70523 RW |
1 | /* |
2 | * kernel/power/suspend.c - Suspend to RAM and standby functionality. | |
3 | * | |
4 | * Copyright (c) 2003 Patrick Mochel | |
5 | * Copyright (c) 2003 Open Source Development Lab | |
6 | * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. | |
7 | * | |
8 | * This file is released under the GPLv2. | |
9 | */ | |
10 | ||
11 | #include <linux/string.h> | |
12 | #include <linux/delay.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/init.h> | |
15 | #include <linux/console.h> | |
16 | #include <linux/cpu.h> | |
17 | #include <linux/syscalls.h> | |
5a0e3ad6 | 18 | #include <linux/gfp.h> |
dd4c4f17 MG |
19 | #include <linux/io.h> |
20 | #include <linux/kernel.h> | |
21 | #include <linux/list.h> | |
22 | #include <linux/mm.h> | |
23 | #include <linux/slab.h> | |
6e5fdeed | 24 | #include <linux/export.h> |
dd4c4f17 | 25 | #include <linux/suspend.h> |
40dc166c | 26 | #include <linux/syscore_ops.h> |
443772d4 | 27 | #include <linux/ftrace.h> |
938cfed1 | 28 | #include <trace/events/power.h> |
a9d70523 RW |
29 | |
30 | #include "power.h" | |
31 | ||
32 | const char *const pm_states[PM_SUSPEND_MAX] = { | |
7e73c5ae | 33 | [PM_SUSPEND_FREEZE] = "freeze", |
a9d70523 RW |
34 | [PM_SUSPEND_STANDBY] = "standby", |
35 | [PM_SUSPEND_MEM] = "mem", | |
36 | }; | |
37 | ||
2f55ac07 | 38 | static const struct platform_suspend_ops *suspend_ops; |
a9d70523 | 39 | |
7e73c5ae ZR |
40 | static bool need_suspend_ops(suspend_state_t state) |
41 | { | |
7500d936 | 42 | return state > PM_SUSPEND_FREEZE; |
7e73c5ae ZR |
43 | } |
44 | ||
45 | static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head); | |
46 | static bool suspend_freeze_wake; | |
47 | ||
48 | static void freeze_begin(void) | |
49 | { | |
50 | suspend_freeze_wake = false; | |
51 | } | |
52 | ||
53 | static void freeze_enter(void) | |
54 | { | |
55 | wait_event(suspend_freeze_wait_head, suspend_freeze_wake); | |
56 | } | |
57 | ||
58 | void freeze_wake(void) | |
59 | { | |
60 | suspend_freeze_wake = true; | |
61 | wake_up(&suspend_freeze_wait_head); | |
62 | } | |
63 | EXPORT_SYMBOL_GPL(freeze_wake); | |
64 | ||
a9d70523 | 65 | /** |
55ae4519 RW |
66 | * suspend_set_ops - Set the global suspend method table. |
67 | * @ops: Suspend operations to use. | |
a9d70523 | 68 | */ |
2f55ac07 | 69 | void suspend_set_ops(const struct platform_suspend_ops *ops) |
a9d70523 | 70 | { |
bcda53fa | 71 | lock_system_sleep(); |
a9d70523 | 72 | suspend_ops = ops; |
bcda53fa | 73 | unlock_system_sleep(); |
a9d70523 | 74 | } |
a5e4fd87 | 75 | EXPORT_SYMBOL_GPL(suspend_set_ops); |
a9d70523 RW |
76 | |
77 | bool valid_state(suspend_state_t state) | |
78 | { | |
c26b78a2 ZR |
79 | if (state == PM_SUSPEND_FREEZE) { |
80 | #ifdef CONFIG_PM_DEBUG | |
81 | if (pm_test_level != TEST_NONE && | |
82 | pm_test_level != TEST_FREEZER && | |
83 | pm_test_level != TEST_DEVICES && | |
84 | pm_test_level != TEST_PLATFORM) { | |
85 | printk(KERN_WARNING "Unsupported pm_test mode for " | |
86 | "freeze state, please choose " | |
87 | "none/freezer/devices/platform.\n"); | |
88 | return false; | |
89 | } | |
90 | #endif | |
91 | return true; | |
92 | } | |
a9d70523 | 93 | /* |
7e73c5ae ZR |
94 | * PM_SUSPEND_STANDBY and PM_SUSPEND_MEMORY states need lowlevel |
95 | * support and need to be valid to the lowlevel | |
a9d70523 RW |
96 | * implementation, no valid callback implies that none are valid. |
97 | */ | |
98 | return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); | |
99 | } | |
100 | ||
101 | /** | |
55ae4519 | 102 | * suspend_valid_only_mem - Generic memory-only valid callback. |
a9d70523 | 103 | * |
55ae4519 RW |
104 | * Platform drivers that implement mem suspend only and only need to check for |
105 | * that in their .valid() callback can use this instead of rolling their own | |
106 | * .valid() callback. | |
a9d70523 RW |
107 | */ |
108 | int suspend_valid_only_mem(suspend_state_t state) | |
109 | { | |
110 | return state == PM_SUSPEND_MEM; | |
111 | } | |
a5e4fd87 | 112 | EXPORT_SYMBOL_GPL(suspend_valid_only_mem); |
a9d70523 RW |
113 | |
114 | static int suspend_test(int level) | |
115 | { | |
116 | #ifdef CONFIG_PM_DEBUG | |
117 | if (pm_test_level == level) { | |
118 | printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); | |
119 | mdelay(5000); | |
120 | return 1; | |
121 | } | |
122 | #endif /* !CONFIG_PM_DEBUG */ | |
123 | return 0; | |
124 | } | |
125 | ||
126 | /** | |
55ae4519 | 127 | * suspend_prepare - Prepare for entering system sleep state. |
a9d70523 | 128 | * |
55ae4519 RW |
129 | * Common code run for every system sleep state that can be entered (except for |
130 | * hibernation). Run suspend notifiers, allocate the "suspend" console and | |
131 | * freeze processes. | |
a9d70523 | 132 | */ |
7e73c5ae | 133 | static int suspend_prepare(suspend_state_t state) |
a9d70523 RW |
134 | { |
135 | int error; | |
136 | ||
7e73c5ae | 137 | if (need_suspend_ops(state) && (!suspend_ops || !suspend_ops->enter)) |
a9d70523 RW |
138 | return -EPERM; |
139 | ||
140 | pm_prepare_console(); | |
141 | ||
142 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); | |
143 | if (error) | |
144 | goto Finish; | |
145 | ||
a9d70523 | 146 | error = suspend_freeze_processes(); |
03afed8b | 147 | if (!error) |
a9d70523 RW |
148 | return 0; |
149 | ||
03afed8b TH |
150 | suspend_stats.failed_freeze++; |
151 | dpm_save_failed_step(SUSPEND_FREEZE); | |
a9d70523 RW |
152 | Finish: |
153 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
154 | pm_restore_console(); | |
155 | return error; | |
156 | } | |
157 | ||
158 | /* default implementation */ | |
159 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
160 | { | |
161 | local_irq_disable(); | |
162 | } | |
163 | ||
164 | /* default implementation */ | |
165 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
166 | { | |
167 | local_irq_enable(); | |
168 | } | |
169 | ||
170 | /** | |
55ae4519 RW |
171 | * suspend_enter - Make the system enter the given sleep state. |
172 | * @state: System sleep state to enter. | |
173 | * @wakeup: Returns information that the sleep state should not be re-entered. | |
a9d70523 | 174 | * |
3b5fe852 | 175 | * This function should be called after devices have been suspended. |
a9d70523 | 176 | */ |
3b5fe852 | 177 | static int suspend_enter(suspend_state_t state, bool *wakeup) |
a9d70523 RW |
178 | { |
179 | int error; | |
180 | ||
7e73c5ae | 181 | if (need_suspend_ops(state) && suspend_ops->prepare) { |
a9d70523 RW |
182 | error = suspend_ops->prepare(); |
183 | if (error) | |
ce441011 | 184 | goto Platform_finish; |
a9d70523 RW |
185 | } |
186 | ||
cf579dfb | 187 | error = dpm_suspend_end(PMSG_SUSPEND); |
a9d70523 RW |
188 | if (error) { |
189 | printk(KERN_ERR "PM: Some devices failed to power down\n"); | |
ce441011 | 190 | goto Platform_finish; |
a9d70523 RW |
191 | } |
192 | ||
7e73c5ae | 193 | if (need_suspend_ops(state) && suspend_ops->prepare_late) { |
a9d70523 RW |
194 | error = suspend_ops->prepare_late(); |
195 | if (error) | |
ce441011 | 196 | goto Platform_wake; |
a9d70523 RW |
197 | } |
198 | ||
08605acc ZR |
199 | if (suspend_test(TEST_PLATFORM)) |
200 | goto Platform_wake; | |
201 | ||
7e73c5ae ZR |
202 | /* |
203 | * PM_SUSPEND_FREEZE equals | |
204 | * frozen processes + suspended devices + idle processors. | |
205 | * Thus we should invoke freeze_enter() soon after | |
206 | * all the devices are suspended. | |
207 | */ | |
208 | if (state == PM_SUSPEND_FREEZE) { | |
209 | freeze_enter(); | |
210 | goto Platform_wake; | |
211 | } | |
212 | ||
3831261e | 213 | ftrace_stop(); |
a9d70523 RW |
214 | error = disable_nonboot_cpus(); |
215 | if (error || suspend_test(TEST_CPUS)) | |
216 | goto Enable_cpus; | |
217 | ||
218 | arch_suspend_disable_irqs(); | |
219 | BUG_ON(!irqs_disabled()); | |
220 | ||
2e711c04 | 221 | error = syscore_suspend(); |
a9d70523 | 222 | if (!error) { |
3b5fe852 MH |
223 | *wakeup = pm_wakeup_pending(); |
224 | if (!(suspend_test(TEST_CORE) || *wakeup)) { | |
a9d70523 | 225 | error = suspend_ops->enter(state); |
c125e96f RW |
226 | events_check_enabled = false; |
227 | } | |
40dc166c | 228 | syscore_resume(); |
a9d70523 RW |
229 | } |
230 | ||
231 | arch_suspend_enable_irqs(); | |
232 | BUG_ON(irqs_disabled()); | |
233 | ||
234 | Enable_cpus: | |
235 | enable_nonboot_cpus(); | |
3831261e | 236 | ftrace_start(); |
a9d70523 RW |
237 | |
238 | Platform_wake: | |
7e73c5ae | 239 | if (need_suspend_ops(state) && suspend_ops->wake) |
a9d70523 RW |
240 | suspend_ops->wake(); |
241 | ||
cf579dfb | 242 | dpm_resume_start(PMSG_RESUME); |
a9d70523 | 243 | |
ce441011 | 244 | Platform_finish: |
7e73c5ae | 245 | if (need_suspend_ops(state) && suspend_ops->finish) |
a9d70523 RW |
246 | suspend_ops->finish(); |
247 | ||
248 | return error; | |
249 | } | |
250 | ||
251 | /** | |
55ae4519 RW |
252 | * suspend_devices_and_enter - Suspend devices and enter system sleep state. |
253 | * @state: System sleep state to enter. | |
a9d70523 RW |
254 | */ |
255 | int suspend_devices_and_enter(suspend_state_t state) | |
256 | { | |
257 | int error; | |
3b5fe852 | 258 | bool wakeup = false; |
a9d70523 | 259 | |
7e73c5ae | 260 | if (need_suspend_ops(state) && !suspend_ops) |
a9d70523 RW |
261 | return -ENOSYS; |
262 | ||
938cfed1 | 263 | trace_machine_suspend(state); |
7e73c5ae | 264 | if (need_suspend_ops(state) && suspend_ops->begin) { |
a9d70523 RW |
265 | error = suspend_ops->begin(state); |
266 | if (error) | |
267 | goto Close; | |
268 | } | |
269 | suspend_console(); | |
270 | suspend_test_start(); | |
271 | error = dpm_suspend_start(PMSG_SUSPEND); | |
272 | if (error) { | |
9350de06 | 273 | pr_err("PM: Some devices failed to suspend, or early wake event detected\n"); |
a9d70523 RW |
274 | goto Recover_platform; |
275 | } | |
276 | suspend_test_finish("suspend devices"); | |
277 | if (suspend_test(TEST_DEVICES)) | |
278 | goto Recover_platform; | |
279 | ||
3b5fe852 MH |
280 | do { |
281 | error = suspend_enter(state, &wakeup); | |
7e73c5ae | 282 | } while (!error && !wakeup && need_suspend_ops(state) |
3b5fe852 | 283 | && suspend_ops->suspend_again && suspend_ops->suspend_again()); |
a9d70523 RW |
284 | |
285 | Resume_devices: | |
286 | suspend_test_start(); | |
287 | dpm_resume_end(PMSG_RESUME); | |
288 | suspend_test_finish("resume devices"); | |
289 | resume_console(); | |
290 | Close: | |
7e73c5ae | 291 | if (need_suspend_ops(state) && suspend_ops->end) |
a9d70523 | 292 | suspend_ops->end(); |
938cfed1 | 293 | trace_machine_suspend(PWR_EVENT_EXIT); |
a9d70523 RW |
294 | return error; |
295 | ||
296 | Recover_platform: | |
7e73c5ae | 297 | if (need_suspend_ops(state) && suspend_ops->recover) |
a9d70523 RW |
298 | suspend_ops->recover(); |
299 | goto Resume_devices; | |
300 | } | |
301 | ||
302 | /** | |
55ae4519 | 303 | * suspend_finish - Clean up before finishing the suspend sequence. |
a9d70523 | 304 | * |
55ae4519 RW |
305 | * Call platform code to clean up, restart processes, and free the console that |
306 | * we've allocated. This routine is not called for hibernation. | |
a9d70523 RW |
307 | */ |
308 | static void suspend_finish(void) | |
309 | { | |
310 | suspend_thaw_processes(); | |
a9d70523 RW |
311 | pm_notifier_call_chain(PM_POST_SUSPEND); |
312 | pm_restore_console(); | |
313 | } | |
314 | ||
315 | /** | |
55ae4519 RW |
316 | * enter_state - Do common work needed to enter system sleep state. |
317 | * @state: System sleep state to enter. | |
a9d70523 | 318 | * |
55ae4519 RW |
319 | * Make sure that no one else is trying to put the system into a sleep state. |
320 | * Fail if that's not the case. Otherwise, prepare for system suspend, make the | |
321 | * system enter the given sleep state and clean up after wakeup. | |
a9d70523 | 322 | */ |
93e1ee43 | 323 | static int enter_state(suspend_state_t state) |
a9d70523 RW |
324 | { |
325 | int error; | |
326 | ||
327 | if (!valid_state(state)) | |
328 | return -ENODEV; | |
329 | ||
330 | if (!mutex_trylock(&pm_mutex)) | |
331 | return -EBUSY; | |
332 | ||
7e73c5ae ZR |
333 | if (state == PM_SUSPEND_FREEZE) |
334 | freeze_begin(); | |
335 | ||
a9d70523 RW |
336 | printk(KERN_INFO "PM: Syncing filesystems ... "); |
337 | sys_sync(); | |
338 | printk("done.\n"); | |
339 | ||
340 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); | |
7e73c5ae | 341 | error = suspend_prepare(state); |
a9d70523 RW |
342 | if (error) |
343 | goto Unlock; | |
344 | ||
345 | if (suspend_test(TEST_FREEZER)) | |
346 | goto Finish; | |
347 | ||
348 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); | |
87186475 | 349 | pm_restrict_gfp_mask(); |
a9d70523 | 350 | error = suspend_devices_and_enter(state); |
87186475 | 351 | pm_restore_gfp_mask(); |
a9d70523 RW |
352 | |
353 | Finish: | |
354 | pr_debug("PM: Finishing wakeup.\n"); | |
355 | suspend_finish(); | |
356 | Unlock: | |
357 | mutex_unlock(&pm_mutex); | |
358 | return error; | |
359 | } | |
360 | ||
361 | /** | |
55ae4519 RW |
362 | * pm_suspend - Externally visible function for suspending the system. |
363 | * @state: System sleep state to enter. | |
a9d70523 | 364 | * |
55ae4519 RW |
365 | * Check if the value of @state represents one of the supported states, |
366 | * execute enter_state() and update system suspend statistics. | |
a9d70523 RW |
367 | */ |
368 | int pm_suspend(suspend_state_t state) | |
369 | { | |
bc25cf50 RW |
370 | int error; |
371 | ||
372 | if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX) | |
373 | return -EINVAL; | |
374 | ||
375 | error = enter_state(state); | |
376 | if (error) { | |
377 | suspend_stats.fail++; | |
378 | dpm_save_failed_errno(error); | |
379 | } else { | |
380 | suspend_stats.success++; | |
2a77c46d | 381 | } |
bc25cf50 | 382 | return error; |
a9d70523 RW |
383 | } |
384 | EXPORT_SYMBOL(pm_suspend); |