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> |
1da177e4 LT |
23 | |
24 | #include "power.h" | |
25 | ||
5ae947ec DSL |
26 | /*This is just an arbitrary number */ |
27 | #define FREE_PAGE_NUMBER (100) | |
28 | ||
a6d70980 | 29 | DEFINE_MUTEX(pm_mutex); |
1da177e4 | 30 | |
123d3c13 | 31 | struct pm_ops *pm_ops; |
1da177e4 LT |
32 | |
33 | /** | |
34 | * pm_set_ops - Set the global power method table. | |
35 | * @ops: Pointer to ops structure. | |
36 | */ | |
37 | ||
38 | void pm_set_ops(struct pm_ops * ops) | |
39 | { | |
a6d70980 | 40 | mutex_lock(&pm_mutex); |
1da177e4 | 41 | pm_ops = ops; |
a6d70980 | 42 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
43 | } |
44 | ||
e8c9c502 JB |
45 | /** |
46 | * pm_valid_only_mem - generic memory-only valid callback | |
47 | * | |
48 | * pm_ops drivers that implement mem suspend only and only need | |
49 | * to check for that in their .valid callback can use this instead | |
50 | * of rolling their own .valid callback. | |
51 | */ | |
52 | int pm_valid_only_mem(suspend_state_t state) | |
53 | { | |
54 | return state == PM_SUSPEND_MEM; | |
55 | } | |
56 | ||
57 | ||
e3c7db62 RW |
58 | static inline void pm_finish(suspend_state_t state) |
59 | { | |
60 | if (pm_ops->finish) | |
61 | pm_ops->finish(state); | |
62 | } | |
1da177e4 LT |
63 | |
64 | /** | |
65 | * suspend_prepare - Do prep work before entering low-power state. | |
66 | * @state: State we're entering. | |
67 | * | |
68 | * This is common code that is called for each state that we're | |
69 | * entering. Allocate a console, stop all processes, then make sure | |
70 | * the platform can enter the requested state. | |
71 | */ | |
72 | ||
73 | static int suspend_prepare(suspend_state_t state) | |
74 | { | |
e3920fb4 | 75 | int error; |
5ae947ec | 76 | unsigned int free_pages; |
1da177e4 LT |
77 | |
78 | if (!pm_ops || !pm_ops->enter) | |
79 | return -EPERM; | |
80 | ||
81 | pm_prepare_console(); | |
82 | ||
83 | if (freeze_processes()) { | |
84 | error = -EAGAIN; | |
85 | goto Thaw; | |
86 | } | |
87 | ||
96177299 CL |
88 | if ((free_pages = global_page_state(NR_FREE_PAGES)) |
89 | < FREE_PAGE_NUMBER) { | |
5ae947ec DSL |
90 | pr_debug("PM: free some memory\n"); |
91 | shrink_all_memory(FREE_PAGE_NUMBER - free_pages); | |
92 | if (nr_free_pages() < FREE_PAGE_NUMBER) { | |
93 | error = -ENOMEM; | |
94 | printk(KERN_ERR "PM: No enough memory\n"); | |
95 | goto Thaw; | |
96 | } | |
97 | } | |
98 | ||
2391dae3 RW |
99 | if (pm_ops->set_target) { |
100 | error = pm_ops->set_target(state); | |
101 | if (error) | |
102 | goto Thaw; | |
103 | } | |
557240b4 | 104 | suspend_console(); |
e3c7db62 RW |
105 | error = device_suspend(PMSG_SUSPEND); |
106 | if (error) { | |
1da177e4 | 107 | printk(KERN_ERR "Some devices failed to suspend\n"); |
52ade9b3 | 108 | goto Resume_console; |
1da177e4 | 109 | } |
52ade9b3 LT |
110 | if (pm_ops->prepare) { |
111 | if ((error = pm_ops->prepare(state))) | |
112 | goto Resume_devices; | |
113 | } | |
114 | ||
e3c7db62 RW |
115 | error = disable_nonboot_cpus(); |
116 | if (!error) | |
117 | return 0; | |
118 | ||
119 | enable_nonboot_cpus(); | |
e3c7db62 | 120 | pm_finish(state); |
52ade9b3 | 121 | Resume_devices: |
e3c7db62 | 122 | device_resume(); |
52ade9b3 | 123 | Resume_console: |
e3c7db62 | 124 | resume_console(); |
1da177e4 LT |
125 | Thaw: |
126 | thaw_processes(); | |
127 | pm_restore_console(); | |
128 | return error; | |
129 | } | |
130 | ||
a53c46dc JB |
131 | /* default implementation */ |
132 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
133 | { | |
134 | local_irq_disable(); | |
135 | } | |
136 | ||
137 | /* default implementation */ | |
138 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
139 | { | |
140 | local_irq_enable(); | |
141 | } | |
1da177e4 | 142 | |
9b238205 | 143 | int suspend_enter(suspend_state_t state) |
1da177e4 LT |
144 | { |
145 | int error = 0; | |
1da177e4 | 146 | |
a53c46dc JB |
147 | arch_suspend_disable_irqs(); |
148 | BUG_ON(!irqs_disabled()); | |
1da177e4 LT |
149 | |
150 | if ((error = device_power_down(PMSG_SUSPEND))) { | |
151 | printk(KERN_ERR "Some devices failed to power down\n"); | |
152 | goto Done; | |
153 | } | |
154 | error = pm_ops->enter(state); | |
155 | device_power_up(); | |
156 | Done: | |
a53c46dc JB |
157 | arch_suspend_enable_irqs(); |
158 | BUG_ON(irqs_disabled()); | |
1da177e4 LT |
159 | return error; |
160 | } | |
161 | ||
162 | ||
163 | /** | |
164 | * suspend_finish - Do final work before exiting suspend sequence. | |
165 | * @state: State we're coming out of. | |
166 | * | |
167 | * Call platform code to clean up, restart processes, and free the | |
168 | * console that we've allocated. This is not called for suspend-to-disk. | |
169 | */ | |
170 | ||
171 | static void suspend_finish(suspend_state_t state) | |
172 | { | |
e3c7db62 RW |
173 | enable_nonboot_cpus(); |
174 | pm_finish(state); | |
1da177e4 | 175 | device_resume(); |
557240b4 | 176 | resume_console(); |
1da177e4 LT |
177 | thaw_processes(); |
178 | pm_restore_console(); | |
179 | } | |
180 | ||
181 | ||
182 | ||
183 | ||
3b364b8d | 184 | static const char * const pm_states[PM_SUSPEND_MAX] = { |
1da177e4 LT |
185 | [PM_SUSPEND_STANDBY] = "standby", |
186 | [PM_SUSPEND_MEM] = "mem", | |
1da177e4 LT |
187 | }; |
188 | ||
123d3c13 PM |
189 | static inline int valid_state(suspend_state_t state) |
190 | { | |
a3d25c27 RW |
191 | /* All states need lowlevel support and need to be valid |
192 | * to the lowlevel implementation, no valid callback | |
9684e51c JB |
193 | * implies that none are valid. */ |
194 | if (!pm_ops || !pm_ops->valid || !pm_ops->valid(state)) | |
123d3c13 PM |
195 | return 0; |
196 | return 1; | |
197 | } | |
198 | ||
1da177e4 LT |
199 | |
200 | /** | |
201 | * enter_state - Do common work of entering low-power state. | |
202 | * @state: pm_state structure for state we're entering. | |
203 | * | |
204 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
205 | * if someone has beat us to it, since we don't want anything weird to | |
206 | * happen when we wake up. | |
207 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
208 | * we've woken up). | |
209 | */ | |
210 | ||
211 | static int enter_state(suspend_state_t state) | |
212 | { | |
213 | int error; | |
214 | ||
123d3c13 | 215 | if (!valid_state(state)) |
eb9289eb | 216 | return -ENODEV; |
a6d70980 | 217 | if (!mutex_trylock(&pm_mutex)) |
1da177e4 LT |
218 | return -EBUSY; |
219 | ||
82428b62 | 220 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
1da177e4 LT |
221 | if ((error = suspend_prepare(state))) |
222 | goto Unlock; | |
223 | ||
82428b62 | 224 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
1da177e4 LT |
225 | error = suspend_enter(state); |
226 | ||
82428b62 | 227 | pr_debug("PM: Finishing wakeup.\n"); |
1da177e4 LT |
228 | suspend_finish(state); |
229 | Unlock: | |
a6d70980 | 230 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
231 | return error; |
232 | } | |
233 | ||
1da177e4 LT |
234 | |
235 | /** | |
236 | * pm_suspend - Externally visible function for suspending system. | |
a3d25c27 | 237 | * @state: Enumerated value of state to enter. |
1da177e4 LT |
238 | * |
239 | * Determine whether or not value is within range, get state | |
240 | * structure, and enter (above). | |
241 | */ | |
242 | ||
243 | int pm_suspend(suspend_state_t state) | |
244 | { | |
e2a5b420 | 245 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
1da177e4 LT |
246 | return enter_state(state); |
247 | return -EINVAL; | |
248 | } | |
249 | ||
4cf30348 | 250 | EXPORT_SYMBOL(pm_suspend); |
1da177e4 LT |
251 | |
252 | decl_subsys(power,NULL,NULL); | |
253 | ||
254 | ||
255 | /** | |
256 | * state - control system power state. | |
257 | * | |
258 | * show() returns what states are supported, which is hard-coded to | |
259 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and | |
260 | * 'disk' (Suspend-to-Disk). | |
261 | * | |
262 | * store() accepts one of those strings, translates it into the | |
263 | * proper enumerated value, and initiates a suspend transition. | |
264 | */ | |
265 | ||
823bccfc | 266 | static ssize_t state_show(struct kset *kset, char *buf) |
1da177e4 LT |
267 | { |
268 | int i; | |
269 | char * s = buf; | |
270 | ||
271 | for (i = 0; i < PM_SUSPEND_MAX; i++) { | |
123d3c13 PM |
272 | if (pm_states[i] && valid_state(i)) |
273 | s += sprintf(s,"%s ", pm_states[i]); | |
1da177e4 | 274 | } |
a3d25c27 RW |
275 | #ifdef CONFIG_SOFTWARE_SUSPEND |
276 | s += sprintf(s, "%s\n", "disk"); | |
277 | #else | |
278 | if (s != buf) | |
279 | /* convert the last space to a newline */ | |
280 | *(s-1) = '\n'; | |
281 | #endif | |
1da177e4 LT |
282 | return (s - buf); |
283 | } | |
284 | ||
823bccfc | 285 | static ssize_t state_store(struct kset *kset, const char *buf, size_t n) |
1da177e4 LT |
286 | { |
287 | suspend_state_t state = PM_SUSPEND_STANDBY; | |
3b364b8d | 288 | const char * const *s; |
1da177e4 LT |
289 | char *p; |
290 | int error; | |
291 | int len; | |
292 | ||
293 | p = memchr(buf, '\n', n); | |
294 | len = p ? p - buf : n; | |
295 | ||
a3d25c27 | 296 | /* First, check if we are requested to hibernate */ |
8d98a690 | 297 | if (len == 4 && !strncmp(buf, "disk", len)) { |
a3d25c27 RW |
298 | error = hibernate(); |
299 | return error ? error : n; | |
300 | } | |
301 | ||
1da177e4 | 302 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
8d98a690 | 303 | if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) |
1da177e4 LT |
304 | break; |
305 | } | |
47bb7899 | 306 | if (state < PM_SUSPEND_MAX && *s) |
1da177e4 LT |
307 | error = enter_state(state); |
308 | else | |
309 | error = -EINVAL; | |
310 | return error ? error : n; | |
311 | } | |
312 | ||
313 | power_attr(state); | |
314 | ||
c5c6ba4e RW |
315 | #ifdef CONFIG_PM_TRACE |
316 | int pm_trace_enabled; | |
317 | ||
823bccfc | 318 | static ssize_t pm_trace_show(struct kset *kset, char *buf) |
c5c6ba4e RW |
319 | { |
320 | return sprintf(buf, "%d\n", pm_trace_enabled); | |
321 | } | |
322 | ||
323 | static ssize_t | |
823bccfc | 324 | pm_trace_store(struct kset *kset, const char *buf, size_t n) |
c5c6ba4e RW |
325 | { |
326 | int val; | |
327 | ||
328 | if (sscanf(buf, "%d", &val) == 1) { | |
329 | pm_trace_enabled = !!val; | |
330 | return n; | |
331 | } | |
332 | return -EINVAL; | |
333 | } | |
334 | ||
335 | power_attr(pm_trace); | |
336 | ||
337 | static struct attribute * g[] = { | |
338 | &state_attr.attr, | |
339 | &pm_trace_attr.attr, | |
340 | NULL, | |
341 | }; | |
342 | #else | |
1da177e4 LT |
343 | static struct attribute * g[] = { |
344 | &state_attr.attr, | |
345 | NULL, | |
346 | }; | |
c5c6ba4e | 347 | #endif /* CONFIG_PM_TRACE */ |
1da177e4 LT |
348 | |
349 | static struct attribute_group attr_group = { | |
350 | .attrs = g, | |
351 | }; | |
352 | ||
353 | ||
354 | static int __init pm_init(void) | |
355 | { | |
356 | int error = subsystem_register(&power_subsys); | |
357 | if (!error) | |
823bccfc | 358 | error = sysfs_create_group(&power_subsys.kobj,&attr_group); |
1da177e4 LT |
359 | return error; |
360 | } | |
361 | ||
362 | core_initcall(pm_init); |