]>
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> | |
24 | #include <linux/suspend.h> | |
938cfed1 | 25 | #include <trace/events/power.h> |
a9d70523 RW |
26 | |
27 | #include "power.h" | |
28 | ||
29 | const char *const pm_states[PM_SUSPEND_MAX] = { | |
30 | [PM_SUSPEND_STANDBY] = "standby", | |
31 | [PM_SUSPEND_MEM] = "mem", | |
32 | }; | |
33 | ||
2f55ac07 | 34 | static const struct platform_suspend_ops *suspend_ops; |
a9d70523 RW |
35 | |
36 | /** | |
37 | * suspend_set_ops - Set the global suspend method table. | |
38 | * @ops: Pointer to ops structure. | |
39 | */ | |
2f55ac07 | 40 | void suspend_set_ops(const struct platform_suspend_ops *ops) |
a9d70523 RW |
41 | { |
42 | mutex_lock(&pm_mutex); | |
43 | suspend_ops = ops; | |
44 | mutex_unlock(&pm_mutex); | |
45 | } | |
46 | ||
47 | bool valid_state(suspend_state_t state) | |
48 | { | |
49 | /* | |
50 | * All states need lowlevel support and need to be valid to the lowlevel | |
51 | * implementation, no valid callback implies that none are valid. | |
52 | */ | |
53 | return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); | |
54 | } | |
55 | ||
56 | /** | |
57 | * suspend_valid_only_mem - generic memory-only valid callback | |
58 | * | |
59 | * Platform drivers that implement mem suspend only and only need | |
60 | * to check for that in their .valid callback can use this instead | |
61 | * of rolling their own .valid callback. | |
62 | */ | |
63 | int suspend_valid_only_mem(suspend_state_t state) | |
64 | { | |
65 | return state == PM_SUSPEND_MEM; | |
66 | } | |
67 | ||
68 | static int suspend_test(int level) | |
69 | { | |
70 | #ifdef CONFIG_PM_DEBUG | |
71 | if (pm_test_level == level) { | |
72 | printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); | |
73 | mdelay(5000); | |
74 | return 1; | |
75 | } | |
76 | #endif /* !CONFIG_PM_DEBUG */ | |
77 | return 0; | |
78 | } | |
79 | ||
80 | /** | |
81 | * suspend_prepare - Do prep work before entering low-power state. | |
82 | * | |
83 | * This is common code that is called for each state that we're entering. | |
84 | * Run suspend notifiers, allocate a console and stop all processes. | |
85 | */ | |
86 | static int suspend_prepare(void) | |
87 | { | |
88 | int error; | |
89 | ||
90 | if (!suspend_ops || !suspend_ops->enter) | |
91 | return -EPERM; | |
92 | ||
93 | pm_prepare_console(); | |
94 | ||
95 | error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); | |
96 | if (error) | |
97 | goto Finish; | |
98 | ||
99 | error = usermodehelper_disable(); | |
100 | if (error) | |
101 | goto Finish; | |
102 | ||
103 | error = suspend_freeze_processes(); | |
104 | if (!error) | |
105 | return 0; | |
106 | ||
107 | suspend_thaw_processes(); | |
108 | usermodehelper_enable(); | |
109 | Finish: | |
110 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
111 | pm_restore_console(); | |
112 | return error; | |
113 | } | |
114 | ||
115 | /* default implementation */ | |
116 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
117 | { | |
118 | local_irq_disable(); | |
119 | } | |
120 | ||
121 | /* default implementation */ | |
122 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
123 | { | |
124 | local_irq_enable(); | |
125 | } | |
126 | ||
127 | /** | |
128 | * suspend_enter - enter the desired system sleep state. | |
129 | * @state: state to enter | |
130 | * | |
131 | * This function should be called after devices have been suspended. | |
132 | */ | |
133 | static int suspend_enter(suspend_state_t state) | |
134 | { | |
135 | int error; | |
136 | ||
137 | if (suspend_ops->prepare) { | |
138 | error = suspend_ops->prepare(); | |
139 | if (error) | |
ce441011 | 140 | goto Platform_finish; |
a9d70523 RW |
141 | } |
142 | ||
143 | error = dpm_suspend_noirq(PMSG_SUSPEND); | |
144 | if (error) { | |
145 | printk(KERN_ERR "PM: Some devices failed to power down\n"); | |
ce441011 | 146 | goto Platform_finish; |
a9d70523 RW |
147 | } |
148 | ||
149 | if (suspend_ops->prepare_late) { | |
150 | error = suspend_ops->prepare_late(); | |
151 | if (error) | |
ce441011 | 152 | goto Platform_wake; |
a9d70523 RW |
153 | } |
154 | ||
155 | if (suspend_test(TEST_PLATFORM)) | |
156 | goto Platform_wake; | |
157 | ||
158 | error = disable_nonboot_cpus(); | |
159 | if (error || suspend_test(TEST_CPUS)) | |
160 | goto Enable_cpus; | |
161 | ||
162 | arch_suspend_disable_irqs(); | |
163 | BUG_ON(!irqs_disabled()); | |
164 | ||
165 | error = sysdev_suspend(PMSG_SUSPEND); | |
166 | if (!error) { | |
a2867e08 | 167 | if (!(suspend_test(TEST_CORE) || pm_wakeup_pending())) { |
a9d70523 | 168 | error = suspend_ops->enter(state); |
c125e96f RW |
169 | events_check_enabled = false; |
170 | } | |
a9d70523 RW |
171 | sysdev_resume(); |
172 | } | |
173 | ||
174 | arch_suspend_enable_irqs(); | |
175 | BUG_ON(irqs_disabled()); | |
176 | ||
177 | Enable_cpus: | |
178 | enable_nonboot_cpus(); | |
179 | ||
180 | Platform_wake: | |
181 | if (suspend_ops->wake) | |
182 | suspend_ops->wake(); | |
183 | ||
a9d70523 RW |
184 | dpm_resume_noirq(PMSG_RESUME); |
185 | ||
ce441011 | 186 | Platform_finish: |
a9d70523 RW |
187 | if (suspend_ops->finish) |
188 | suspend_ops->finish(); | |
189 | ||
190 | return error; | |
191 | } | |
192 | ||
193 | /** | |
194 | * suspend_devices_and_enter - suspend devices and enter the desired system | |
195 | * sleep state. | |
196 | * @state: state to enter | |
197 | */ | |
198 | int suspend_devices_and_enter(suspend_state_t state) | |
199 | { | |
200 | int error; | |
201 | ||
202 | if (!suspend_ops) | |
203 | return -ENOSYS; | |
204 | ||
938cfed1 | 205 | trace_machine_suspend(state); |
a9d70523 RW |
206 | if (suspend_ops->begin) { |
207 | error = suspend_ops->begin(state); | |
208 | if (error) | |
209 | goto Close; | |
210 | } | |
211 | suspend_console(); | |
c9e664f1 | 212 | pm_restrict_gfp_mask(); |
a9d70523 RW |
213 | suspend_test_start(); |
214 | error = dpm_suspend_start(PMSG_SUSPEND); | |
215 | if (error) { | |
216 | printk(KERN_ERR "PM: Some devices failed to suspend\n"); | |
217 | goto Recover_platform; | |
218 | } | |
219 | suspend_test_finish("suspend devices"); | |
220 | if (suspend_test(TEST_DEVICES)) | |
221 | goto Recover_platform; | |
222 | ||
223 | suspend_enter(state); | |
224 | ||
225 | Resume_devices: | |
226 | suspend_test_start(); | |
227 | dpm_resume_end(PMSG_RESUME); | |
228 | suspend_test_finish("resume devices"); | |
c9e664f1 | 229 | pm_restore_gfp_mask(); |
a9d70523 RW |
230 | resume_console(); |
231 | Close: | |
232 | if (suspend_ops->end) | |
233 | suspend_ops->end(); | |
938cfed1 | 234 | trace_machine_suspend(PWR_EVENT_EXIT); |
a9d70523 RW |
235 | return error; |
236 | ||
237 | Recover_platform: | |
238 | if (suspend_ops->recover) | |
239 | suspend_ops->recover(); | |
240 | goto Resume_devices; | |
241 | } | |
242 | ||
243 | /** | |
244 | * suspend_finish - Do final work before exiting suspend sequence. | |
245 | * | |
246 | * Call platform code to clean up, restart processes, and free the | |
247 | * console that we've allocated. This is not called for suspend-to-disk. | |
248 | */ | |
249 | static void suspend_finish(void) | |
250 | { | |
251 | suspend_thaw_processes(); | |
252 | usermodehelper_enable(); | |
253 | pm_notifier_call_chain(PM_POST_SUSPEND); | |
254 | pm_restore_console(); | |
255 | } | |
256 | ||
257 | /** | |
258 | * enter_state - Do common work of entering low-power state. | |
259 | * @state: pm_state structure for state we're entering. | |
260 | * | |
261 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
262 | * if someone has beat us to it, since we don't want anything weird to | |
263 | * happen when we wake up. | |
264 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
265 | * we've woken up). | |
266 | */ | |
267 | int enter_state(suspend_state_t state) | |
268 | { | |
269 | int error; | |
270 | ||
271 | if (!valid_state(state)) | |
272 | return -ENODEV; | |
273 | ||
274 | if (!mutex_trylock(&pm_mutex)) | |
275 | return -EBUSY; | |
276 | ||
277 | printk(KERN_INFO "PM: Syncing filesystems ... "); | |
278 | sys_sync(); | |
279 | printk("done.\n"); | |
280 | ||
281 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); | |
282 | error = suspend_prepare(); | |
283 | if (error) | |
284 | goto Unlock; | |
285 | ||
286 | if (suspend_test(TEST_FREEZER)) | |
287 | goto Finish; | |
288 | ||
289 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); | |
290 | error = suspend_devices_and_enter(state); | |
291 | ||
292 | Finish: | |
293 | pr_debug("PM: Finishing wakeup.\n"); | |
294 | suspend_finish(); | |
295 | Unlock: | |
296 | mutex_unlock(&pm_mutex); | |
297 | return error; | |
298 | } | |
299 | ||
300 | /** | |
301 | * pm_suspend - Externally visible function for suspending system. | |
302 | * @state: Enumerated value of state to enter. | |
303 | * | |
304 | * Determine whether or not value is within range, get state | |
305 | * structure, and enter (above). | |
306 | */ | |
307 | int pm_suspend(suspend_state_t state) | |
308 | { | |
309 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) | |
310 | return enter_state(state); | |
311 | return -EINVAL; | |
312 | } | |
313 | EXPORT_SYMBOL(pm_suspend); |