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> | |
f3f12532 | 17 | #include <linux/cpuidle.h> |
a9d70523 | 18 | #include <linux/syscalls.h> |
5a0e3ad6 | 19 | #include <linux/gfp.h> |
dd4c4f17 MG |
20 | #include <linux/io.h> |
21 | #include <linux/kernel.h> | |
22 | #include <linux/list.h> | |
23 | #include <linux/mm.h> | |
24 | #include <linux/slab.h> | |
6e5fdeed | 25 | #include <linux/export.h> |
dd4c4f17 | 26 | #include <linux/suspend.h> |
40dc166c | 27 | #include <linux/syscore_ops.h> |
443772d4 | 28 | #include <linux/ftrace.h> |
938cfed1 | 29 | #include <trace/events/power.h> |
52f5684c | 30 | #include <linux/compiler.h> |
a9d70523 RW |
31 | |
32 | #include "power.h" | |
33 | ||
34 | const char *const pm_states[PM_SUSPEND_MAX] = { | |
7e73c5ae | 35 | [PM_SUSPEND_FREEZE] = "freeze", |
a9d70523 RW |
36 | [PM_SUSPEND_STANDBY] = "standby", |
37 | [PM_SUSPEND_MEM] = "mem", | |
38 | }; | |
39 | ||
2f55ac07 | 40 | static const struct platform_suspend_ops *suspend_ops; |
a9d70523 | 41 | |
7e73c5ae ZR |
42 | static bool need_suspend_ops(suspend_state_t state) |
43 | { | |
7500d936 | 44 | return state > PM_SUSPEND_FREEZE; |
7e73c5ae ZR |
45 | } |
46 | ||
47 | static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head); | |
48 | static bool suspend_freeze_wake; | |
49 | ||
50 | static void freeze_begin(void) | |
51 | { | |
52 | suspend_freeze_wake = false; | |
53 | } | |
54 | ||
55 | static void freeze_enter(void) | |
56 | { | |
f3f12532 | 57 | cpuidle_resume(); |
7e73c5ae | 58 | wait_event(suspend_freeze_wait_head, suspend_freeze_wake); |
f3f12532 | 59 | cpuidle_pause(); |
7e73c5ae ZR |
60 | } |
61 | ||
62 | void freeze_wake(void) | |
63 | { | |
64 | suspend_freeze_wake = true; | |
65 | wake_up(&suspend_freeze_wait_head); | |
66 | } | |
67 | EXPORT_SYMBOL_GPL(freeze_wake); | |
68 | ||
a9d70523 | 69 | /** |
55ae4519 RW |
70 | * suspend_set_ops - Set the global suspend method table. |
71 | * @ops: Suspend operations to use. | |
a9d70523 | 72 | */ |
2f55ac07 | 73 | void suspend_set_ops(const struct platform_suspend_ops *ops) |
a9d70523 | 74 | { |
bcda53fa | 75 | lock_system_sleep(); |
a9d70523 | 76 | suspend_ops = ops; |
bcda53fa | 77 | unlock_system_sleep(); |
a9d70523 | 78 | } |
a5e4fd87 | 79 | EXPORT_SYMBOL_GPL(suspend_set_ops); |
a9d70523 RW |
80 | |
81 | bool valid_state(suspend_state_t state) | |
82 | { | |
c26b78a2 ZR |
83 | if (state == PM_SUSPEND_FREEZE) { |
84 | #ifdef CONFIG_PM_DEBUG | |
85 | if (pm_test_level != TEST_NONE && | |
86 | pm_test_level != TEST_FREEZER && | |
87 | pm_test_level != TEST_DEVICES && | |
88 | pm_test_level != TEST_PLATFORM) { | |
89 | printk(KERN_WARNING "Unsupported pm_test mode for " | |
90 | "freeze state, please choose " | |
91 | "none/freezer/devices/platform.\n"); | |
92 | return false; | |
93 | } | |
94 | #endif | |
95 | return true; | |
96 | } | |
a9d70523 | 97 | /* |
7e73c5ae ZR |
98 | * PM_SUSPEND_STANDBY and PM_SUSPEND_MEMORY states need lowlevel |
99 | * support and need to be valid to the lowlevel | |
a9d70523 RW |
100 | * implementation, no valid callback implies that none are valid. |
101 | */ | |
102 | return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); | |
103 | } | |
104 | ||
105 | /** | |
55ae4519 | 106 | * suspend_valid_only_mem - Generic memory-only valid callback. |
a9d70523 | 107 | * |
55ae4519 RW |
108 | * Platform drivers that implement mem suspend only and only need to check for |
109 | * that in their .valid() callback can use this instead of rolling their own | |
110 | * .valid() callback. | |
a9d70523 RW |
111 | */ |
112 | int suspend_valid_only_mem(suspend_state_t state) | |
113 | { | |
114 | return state == PM_SUSPEND_MEM; | |
115 | } | |
a5e4fd87 | 116 | EXPORT_SYMBOL_GPL(suspend_valid_only_mem); |
a9d70523 RW |
117 | |
118 | static int suspend_test(int level) | |
119 | { | |
120 | #ifdef CONFIG_PM_DEBUG | |
121 | if (pm_test_level == level) { | |
122 | printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); | |
123 | mdelay(5000); | |
124 | return 1; | |
125 | } | |
126 | #endif /* !CONFIG_PM_DEBUG */ | |
127 | return 0; | |
128 | } | |
129 | ||
130 | /** | |
55ae4519 | 131 | * suspend_prepare - Prepare for entering system sleep state. |
a9d70523 | 132 | * |
55ae4519 RW |
133 | * Common code run for every system sleep state that can be entered (except for |
134 | * hibernation). Run suspend notifiers, allocate the "suspend" console and | |
135 | * freeze processes. | |
a9d70523 | 136 | */ |
7e73c5ae | 137 | static int suspend_prepare(suspend_state_t state) |
a9d70523 RW |
138 | { |
139 | int error; | |
140 | ||
7e73c5ae | 141 | if (need_suspend_ops(state) && (!suspend_ops || !suspend_ops->enter)) |
a9d70523 RW |
142 | return -EPERM; |
143 | ||
144 | pm_prepare_console(); | |
145 | ||
146 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); | |
147 | if (error) | |
148 | goto Finish; | |
149 | ||
a9d70523 | 150 | error = suspend_freeze_processes(); |
03afed8b | 151 | if (!error) |
a9d70523 RW |
152 | return 0; |
153 | ||
03afed8b TH |
154 | suspend_stats.failed_freeze++; |
155 | dpm_save_failed_step(SUSPEND_FREEZE); | |
a9d70523 RW |
156 | Finish: |
157 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
158 | pm_restore_console(); | |
159 | return error; | |
160 | } | |
161 | ||
162 | /* default implementation */ | |
52f5684c | 163 | void __weak arch_suspend_disable_irqs(void) |
a9d70523 RW |
164 | { |
165 | local_irq_disable(); | |
166 | } | |
167 | ||
168 | /* default implementation */ | |
52f5684c | 169 | void __weak arch_suspend_enable_irqs(void) |
a9d70523 RW |
170 | { |
171 | local_irq_enable(); | |
172 | } | |
173 | ||
174 | /** | |
55ae4519 RW |
175 | * suspend_enter - Make the system enter the given sleep state. |
176 | * @state: System sleep state to enter. | |
177 | * @wakeup: Returns information that the sleep state should not be re-entered. | |
a9d70523 | 178 | * |
3b5fe852 | 179 | * This function should be called after devices have been suspended. |
a9d70523 | 180 | */ |
3b5fe852 | 181 | static int suspend_enter(suspend_state_t state, bool *wakeup) |
a9d70523 RW |
182 | { |
183 | int error; | |
184 | ||
7e73c5ae | 185 | if (need_suspend_ops(state) && suspend_ops->prepare) { |
a9d70523 RW |
186 | error = suspend_ops->prepare(); |
187 | if (error) | |
ce441011 | 188 | goto Platform_finish; |
a9d70523 RW |
189 | } |
190 | ||
cf579dfb | 191 | error = dpm_suspend_end(PMSG_SUSPEND); |
a9d70523 RW |
192 | if (error) { |
193 | printk(KERN_ERR "PM: Some devices failed to power down\n"); | |
ce441011 | 194 | goto Platform_finish; |
a9d70523 RW |
195 | } |
196 | ||
7e73c5ae | 197 | if (need_suspend_ops(state) && suspend_ops->prepare_late) { |
a9d70523 RW |
198 | error = suspend_ops->prepare_late(); |
199 | if (error) | |
ce441011 | 200 | goto Platform_wake; |
a9d70523 RW |
201 | } |
202 | ||
08605acc ZR |
203 | if (suspend_test(TEST_PLATFORM)) |
204 | goto Platform_wake; | |
205 | ||
7e73c5ae ZR |
206 | /* |
207 | * PM_SUSPEND_FREEZE equals | |
208 | * frozen processes + suspended devices + idle processors. | |
209 | * Thus we should invoke freeze_enter() soon after | |
210 | * all the devices are suspended. | |
211 | */ | |
212 | if (state == PM_SUSPEND_FREEZE) { | |
213 | freeze_enter(); | |
214 | goto Platform_wake; | |
215 | } | |
216 | ||
3831261e | 217 | ftrace_stop(); |
a9d70523 RW |
218 | error = disable_nonboot_cpus(); |
219 | if (error || suspend_test(TEST_CPUS)) | |
220 | goto Enable_cpus; | |
221 | ||
222 | arch_suspend_disable_irqs(); | |
223 | BUG_ON(!irqs_disabled()); | |
224 | ||
2e711c04 | 225 | error = syscore_suspend(); |
a9d70523 | 226 | if (!error) { |
3b5fe852 MH |
227 | *wakeup = pm_wakeup_pending(); |
228 | if (!(suspend_test(TEST_CORE) || *wakeup)) { | |
a9d70523 | 229 | error = suspend_ops->enter(state); |
c125e96f RW |
230 | events_check_enabled = false; |
231 | } | |
40dc166c | 232 | syscore_resume(); |
a9d70523 RW |
233 | } |
234 | ||
235 | arch_suspend_enable_irqs(); | |
236 | BUG_ON(irqs_disabled()); | |
237 | ||
238 | Enable_cpus: | |
239 | enable_nonboot_cpus(); | |
3831261e | 240 | ftrace_start(); |
a9d70523 RW |
241 | |
242 | Platform_wake: | |
7e73c5ae | 243 | if (need_suspend_ops(state) && suspend_ops->wake) |
a9d70523 RW |
244 | suspend_ops->wake(); |
245 | ||
cf579dfb | 246 | dpm_resume_start(PMSG_RESUME); |
a9d70523 | 247 | |
ce441011 | 248 | Platform_finish: |
7e73c5ae | 249 | if (need_suspend_ops(state) && suspend_ops->finish) |
a9d70523 RW |
250 | suspend_ops->finish(); |
251 | ||
252 | return error; | |
253 | } | |
254 | ||
255 | /** | |
55ae4519 RW |
256 | * suspend_devices_and_enter - Suspend devices and enter system sleep state. |
257 | * @state: System sleep state to enter. | |
a9d70523 RW |
258 | */ |
259 | int suspend_devices_and_enter(suspend_state_t state) | |
260 | { | |
261 | int error; | |
3b5fe852 | 262 | bool wakeup = false; |
a9d70523 | 263 | |
7e73c5ae | 264 | if (need_suspend_ops(state) && !suspend_ops) |
a9d70523 RW |
265 | return -ENOSYS; |
266 | ||
938cfed1 | 267 | trace_machine_suspend(state); |
7e73c5ae | 268 | if (need_suspend_ops(state) && suspend_ops->begin) { |
a9d70523 RW |
269 | error = suspend_ops->begin(state); |
270 | if (error) | |
271 | goto Close; | |
272 | } | |
273 | suspend_console(); | |
274 | suspend_test_start(); | |
275 | error = dpm_suspend_start(PMSG_SUSPEND); | |
276 | if (error) { | |
9350de06 | 277 | pr_err("PM: Some devices failed to suspend, or early wake event detected\n"); |
a9d70523 RW |
278 | goto Recover_platform; |
279 | } | |
280 | suspend_test_finish("suspend devices"); | |
281 | if (suspend_test(TEST_DEVICES)) | |
282 | goto Recover_platform; | |
283 | ||
3b5fe852 MH |
284 | do { |
285 | error = suspend_enter(state, &wakeup); | |
7e73c5ae | 286 | } while (!error && !wakeup && need_suspend_ops(state) |
3b5fe852 | 287 | && suspend_ops->suspend_again && suspend_ops->suspend_again()); |
a9d70523 RW |
288 | |
289 | Resume_devices: | |
290 | suspend_test_start(); | |
291 | dpm_resume_end(PMSG_RESUME); | |
292 | suspend_test_finish("resume devices"); | |
293 | resume_console(); | |
294 | Close: | |
7e73c5ae | 295 | if (need_suspend_ops(state) && suspend_ops->end) |
a9d70523 | 296 | suspend_ops->end(); |
938cfed1 | 297 | trace_machine_suspend(PWR_EVENT_EXIT); |
a9d70523 RW |
298 | return error; |
299 | ||
300 | Recover_platform: | |
7e73c5ae | 301 | if (need_suspend_ops(state) && suspend_ops->recover) |
a9d70523 RW |
302 | suspend_ops->recover(); |
303 | goto Resume_devices; | |
304 | } | |
305 | ||
306 | /** | |
55ae4519 | 307 | * suspend_finish - Clean up before finishing the suspend sequence. |
a9d70523 | 308 | * |
55ae4519 RW |
309 | * Call platform code to clean up, restart processes, and free the console that |
310 | * we've allocated. This routine is not called for hibernation. | |
a9d70523 RW |
311 | */ |
312 | static void suspend_finish(void) | |
313 | { | |
314 | suspend_thaw_processes(); | |
a9d70523 RW |
315 | pm_notifier_call_chain(PM_POST_SUSPEND); |
316 | pm_restore_console(); | |
317 | } | |
318 | ||
319 | /** | |
55ae4519 RW |
320 | * enter_state - Do common work needed to enter system sleep state. |
321 | * @state: System sleep state to enter. | |
a9d70523 | 322 | * |
55ae4519 RW |
323 | * Make sure that no one else is trying to put the system into a sleep state. |
324 | * Fail if that's not the case. Otherwise, prepare for system suspend, make the | |
325 | * system enter the given sleep state and clean up after wakeup. | |
a9d70523 | 326 | */ |
93e1ee43 | 327 | static int enter_state(suspend_state_t state) |
a9d70523 RW |
328 | { |
329 | int error; | |
330 | ||
331 | if (!valid_state(state)) | |
332 | return -ENODEV; | |
333 | ||
334 | if (!mutex_trylock(&pm_mutex)) | |
335 | return -EBUSY; | |
336 | ||
7e73c5ae ZR |
337 | if (state == PM_SUSPEND_FREEZE) |
338 | freeze_begin(); | |
339 | ||
a9d70523 RW |
340 | printk(KERN_INFO "PM: Syncing filesystems ... "); |
341 | sys_sync(); | |
342 | printk("done.\n"); | |
343 | ||
344 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); | |
7e73c5ae | 345 | error = suspend_prepare(state); |
a9d70523 RW |
346 | if (error) |
347 | goto Unlock; | |
348 | ||
349 | if (suspend_test(TEST_FREEZER)) | |
350 | goto Finish; | |
351 | ||
352 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); | |
87186475 | 353 | pm_restrict_gfp_mask(); |
a9d70523 | 354 | error = suspend_devices_and_enter(state); |
87186475 | 355 | pm_restore_gfp_mask(); |
a9d70523 RW |
356 | |
357 | Finish: | |
358 | pr_debug("PM: Finishing wakeup.\n"); | |
359 | suspend_finish(); | |
360 | Unlock: | |
361 | mutex_unlock(&pm_mutex); | |
362 | return error; | |
363 | } | |
364 | ||
365 | /** | |
55ae4519 RW |
366 | * pm_suspend - Externally visible function for suspending the system. |
367 | * @state: System sleep state to enter. | |
a9d70523 | 368 | * |
55ae4519 RW |
369 | * Check if the value of @state represents one of the supported states, |
370 | * execute enter_state() and update system suspend statistics. | |
a9d70523 RW |
371 | */ |
372 | int pm_suspend(suspend_state_t state) | |
373 | { | |
bc25cf50 RW |
374 | int error; |
375 | ||
376 | if (state <= PM_SUSPEND_ON || state >= PM_SUSPEND_MAX) | |
377 | return -EINVAL; | |
378 | ||
379 | error = enter_state(state); | |
380 | if (error) { | |
381 | suspend_stats.fail++; | |
382 | dpm_save_failed_errno(error); | |
383 | } else { | |
384 | suspend_stats.success++; | |
2a77c46d | 385 | } |
bc25cf50 | 386 | return error; |
a9d70523 RW |
387 | } |
388 | EXPORT_SYMBOL(pm_suspend); |