Commit | Line | Data |
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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> | |
74da1ff7 | 15 | #include <linux/kmod.h> |
a9d70523 RW |
16 | #include <linux/console.h> |
17 | #include <linux/cpu.h> | |
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> |
938cfed1 | 28 | #include <trace/events/power.h> |
a9d70523 RW |
29 | |
30 | #include "power.h" | |
31 | ||
32 | const char *const pm_states[PM_SUSPEND_MAX] = { | |
33 | [PM_SUSPEND_STANDBY] = "standby", | |
34 | [PM_SUSPEND_MEM] = "mem", | |
35 | }; | |
36 | ||
2f55ac07 | 37 | static const struct platform_suspend_ops *suspend_ops; |
a9d70523 RW |
38 | |
39 | /** | |
40 | * suspend_set_ops - Set the global suspend method table. | |
41 | * @ops: Pointer to ops structure. | |
42 | */ | |
2f55ac07 | 43 | void suspend_set_ops(const struct platform_suspend_ops *ops) |
a9d70523 | 44 | { |
bcda53fa | 45 | lock_system_sleep(); |
a9d70523 | 46 | suspend_ops = ops; |
bcda53fa | 47 | unlock_system_sleep(); |
a9d70523 | 48 | } |
a5e4fd87 | 49 | EXPORT_SYMBOL_GPL(suspend_set_ops); |
a9d70523 RW |
50 | |
51 | bool valid_state(suspend_state_t state) | |
52 | { | |
53 | /* | |
54 | * All states need lowlevel support and need to be valid to the lowlevel | |
55 | * implementation, no valid callback implies that none are valid. | |
56 | */ | |
57 | return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); | |
58 | } | |
59 | ||
60 | /** | |
61 | * suspend_valid_only_mem - generic memory-only valid callback | |
62 | * | |
63 | * Platform drivers that implement mem suspend only and only need | |
64 | * to check for that in their .valid callback can use this instead | |
65 | * of rolling their own .valid callback. | |
66 | */ | |
67 | int suspend_valid_only_mem(suspend_state_t state) | |
68 | { | |
69 | return state == PM_SUSPEND_MEM; | |
70 | } | |
a5e4fd87 | 71 | EXPORT_SYMBOL_GPL(suspend_valid_only_mem); |
a9d70523 RW |
72 | |
73 | static int suspend_test(int level) | |
74 | { | |
75 | #ifdef CONFIG_PM_DEBUG | |
76 | if (pm_test_level == level) { | |
77 | printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); | |
78 | mdelay(5000); | |
79 | return 1; | |
80 | } | |
81 | #endif /* !CONFIG_PM_DEBUG */ | |
82 | return 0; | |
83 | } | |
84 | ||
85 | /** | |
86 | * suspend_prepare - Do prep work before entering low-power state. | |
87 | * | |
88 | * This is common code that is called for each state that we're entering. | |
89 | * Run suspend notifiers, allocate a console and stop all processes. | |
90 | */ | |
91 | static int suspend_prepare(void) | |
92 | { | |
93 | int error; | |
94 | ||
95 | if (!suspend_ops || !suspend_ops->enter) | |
96 | return -EPERM; | |
97 | ||
98 | pm_prepare_console(); | |
99 | ||
100 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); | |
101 | if (error) | |
102 | goto Finish; | |
103 | ||
104 | error = usermodehelper_disable(); | |
105 | if (error) | |
106 | goto Finish; | |
107 | ||
108 | error = suspend_freeze_processes(); | |
03afed8b | 109 | if (!error) |
a9d70523 RW |
110 | return 0; |
111 | ||
03afed8b TH |
112 | suspend_stats.failed_freeze++; |
113 | dpm_save_failed_step(SUSPEND_FREEZE); | |
a9d70523 RW |
114 | usermodehelper_enable(); |
115 | Finish: | |
116 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
117 | pm_restore_console(); | |
118 | return error; | |
119 | } | |
120 | ||
121 | /* default implementation */ | |
122 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
123 | { | |
124 | local_irq_disable(); | |
125 | } | |
126 | ||
127 | /* default implementation */ | |
128 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
129 | { | |
130 | local_irq_enable(); | |
131 | } | |
132 | ||
133 | /** | |
3b5fe852 MH |
134 | * suspend_enter - enter the desired system sleep state. |
135 | * @state: State to enter | |
136 | * @wakeup: Returns information that suspend should not be entered again. | |
a9d70523 | 137 | * |
3b5fe852 | 138 | * This function should be called after devices have been suspended. |
a9d70523 | 139 | */ |
3b5fe852 | 140 | static int suspend_enter(suspend_state_t state, bool *wakeup) |
a9d70523 RW |
141 | { |
142 | int error; | |
143 | ||
144 | if (suspend_ops->prepare) { | |
145 | error = suspend_ops->prepare(); | |
146 | if (error) | |
ce441011 | 147 | goto Platform_finish; |
a9d70523 RW |
148 | } |
149 | ||
150 | error = dpm_suspend_noirq(PMSG_SUSPEND); | |
151 | if (error) { | |
152 | printk(KERN_ERR "PM: Some devices failed to power down\n"); | |
ce441011 | 153 | goto Platform_finish; |
a9d70523 RW |
154 | } |
155 | ||
156 | if (suspend_ops->prepare_late) { | |
157 | error = suspend_ops->prepare_late(); | |
158 | if (error) | |
ce441011 | 159 | goto Platform_wake; |
a9d70523 RW |
160 | } |
161 | ||
162 | if (suspend_test(TEST_PLATFORM)) | |
163 | goto Platform_wake; | |
164 | ||
165 | error = disable_nonboot_cpus(); | |
166 | if (error || suspend_test(TEST_CPUS)) | |
167 | goto Enable_cpus; | |
168 | ||
169 | arch_suspend_disable_irqs(); | |
170 | BUG_ON(!irqs_disabled()); | |
171 | ||
2e711c04 | 172 | error = syscore_suspend(); |
a9d70523 | 173 | if (!error) { |
3b5fe852 MH |
174 | *wakeup = pm_wakeup_pending(); |
175 | if (!(suspend_test(TEST_CORE) || *wakeup)) { | |
a9d70523 | 176 | error = suspend_ops->enter(state); |
c125e96f RW |
177 | events_check_enabled = false; |
178 | } | |
40dc166c | 179 | syscore_resume(); |
a9d70523 RW |
180 | } |
181 | ||
182 | arch_suspend_enable_irqs(); | |
183 | BUG_ON(irqs_disabled()); | |
184 | ||
185 | Enable_cpus: | |
186 | enable_nonboot_cpus(); | |
187 | ||
188 | Platform_wake: | |
189 | if (suspend_ops->wake) | |
190 | suspend_ops->wake(); | |
191 | ||
a9d70523 RW |
192 | dpm_resume_noirq(PMSG_RESUME); |
193 | ||
ce441011 | 194 | Platform_finish: |
a9d70523 RW |
195 | if (suspend_ops->finish) |
196 | suspend_ops->finish(); | |
197 | ||
198 | return error; | |
199 | } | |
200 | ||
201 | /** | |
202 | * suspend_devices_and_enter - suspend devices and enter the desired system | |
203 | * sleep state. | |
204 | * @state: state to enter | |
205 | */ | |
206 | int suspend_devices_and_enter(suspend_state_t state) | |
207 | { | |
208 | int error; | |
3b5fe852 | 209 | bool wakeup = false; |
a9d70523 RW |
210 | |
211 | if (!suspend_ops) | |
212 | return -ENOSYS; | |
213 | ||
938cfed1 | 214 | trace_machine_suspend(state); |
a9d70523 RW |
215 | if (suspend_ops->begin) { |
216 | error = suspend_ops->begin(state); | |
217 | if (error) | |
218 | goto Close; | |
219 | } | |
220 | suspend_console(); | |
221 | suspend_test_start(); | |
222 | error = dpm_suspend_start(PMSG_SUSPEND); | |
223 | if (error) { | |
224 | printk(KERN_ERR "PM: Some devices failed to suspend\n"); | |
225 | goto Recover_platform; | |
226 | } | |
227 | suspend_test_finish("suspend devices"); | |
228 | if (suspend_test(TEST_DEVICES)) | |
229 | goto Recover_platform; | |
230 | ||
3b5fe852 MH |
231 | do { |
232 | error = suspend_enter(state, &wakeup); | |
233 | } while (!error && !wakeup | |
234 | && suspend_ops->suspend_again && suspend_ops->suspend_again()); | |
a9d70523 RW |
235 | |
236 | Resume_devices: | |
237 | suspend_test_start(); | |
238 | dpm_resume_end(PMSG_RESUME); | |
239 | suspend_test_finish("resume devices"); | |
240 | resume_console(); | |
241 | Close: | |
242 | if (suspend_ops->end) | |
243 | suspend_ops->end(); | |
938cfed1 | 244 | trace_machine_suspend(PWR_EVENT_EXIT); |
a9d70523 RW |
245 | return error; |
246 | ||
247 | Recover_platform: | |
248 | if (suspend_ops->recover) | |
249 | suspend_ops->recover(); | |
250 | goto Resume_devices; | |
251 | } | |
252 | ||
253 | /** | |
254 | * suspend_finish - Do final work before exiting suspend sequence. | |
255 | * | |
256 | * Call platform code to clean up, restart processes, and free the | |
257 | * console that we've allocated. This is not called for suspend-to-disk. | |
258 | */ | |
259 | static void suspend_finish(void) | |
260 | { | |
261 | suspend_thaw_processes(); | |
262 | usermodehelper_enable(); | |
263 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
264 | pm_restore_console(); | |
265 | } | |
266 | ||
267 | /** | |
268 | * enter_state - Do common work of entering low-power state. | |
269 | * @state: pm_state structure for state we're entering. | |
270 | * | |
271 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
272 | * if someone has beat us to it, since we don't want anything weird to | |
273 | * happen when we wake up. | |
274 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
275 | * we've woken up). | |
276 | */ | |
277 | int enter_state(suspend_state_t state) | |
278 | { | |
279 | int error; | |
280 | ||
281 | if (!valid_state(state)) | |
282 | return -ENODEV; | |
283 | ||
284 | if (!mutex_trylock(&pm_mutex)) | |
285 | return -EBUSY; | |
286 | ||
287 | printk(KERN_INFO "PM: Syncing filesystems ... "); | |
288 | sys_sync(); | |
289 | printk("done.\n"); | |
290 | ||
291 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); | |
292 | error = suspend_prepare(); | |
293 | if (error) | |
294 | goto Unlock; | |
295 | ||
296 | if (suspend_test(TEST_FREEZER)) | |
297 | goto Finish; | |
298 | ||
299 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); | |
87186475 | 300 | pm_restrict_gfp_mask(); |
a9d70523 | 301 | error = suspend_devices_and_enter(state); |
87186475 | 302 | pm_restore_gfp_mask(); |
a9d70523 RW |
303 | |
304 | Finish: | |
305 | pr_debug("PM: Finishing wakeup.\n"); | |
306 | suspend_finish(); | |
307 | Unlock: | |
308 | mutex_unlock(&pm_mutex); | |
309 | return error; | |
310 | } | |
311 | ||
312 | /** | |
313 | * pm_suspend - Externally visible function for suspending system. | |
314 | * @state: Enumerated value of state to enter. | |
315 | * | |
316 | * Determine whether or not value is within range, get state | |
317 | * structure, and enter (above). | |
318 | */ | |
319 | int pm_suspend(suspend_state_t state) | |
320 | { | |
2a77c46d | 321 | int ret; |
528f7ce6 | 322 | if (state > PM_SUSPEND_ON && state < PM_SUSPEND_MAX) { |
2a77c46d SL |
323 | ret = enter_state(state); |
324 | if (ret) { | |
325 | suspend_stats.fail++; | |
326 | dpm_save_failed_errno(ret); | |
327 | } else | |
328 | suspend_stats.success++; | |
329 | return ret; | |
330 | } | |
a9d70523 RW |
331 | return -EINVAL; |
332 | } | |
333 | EXPORT_SYMBOL(pm_suspend); |