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> | |
18 | #include <linux/pm.h> | |
6cc07191 | 19 | #include <linux/console.h> |
e3920fb4 | 20 | #include <linux/cpu.h> |
c5c6ba4e | 21 | #include <linux/resume-trace.h> |
7dfb7103 | 22 | #include <linux/freezer.h> |
96177299 | 23 | #include <linux/vmstat.h> |
1da177e4 LT |
24 | |
25 | #include "power.h" | |
26 | ||
5ae947ec DSL |
27 | /*This is just an arbitrary number */ |
28 | #define FREE_PAGE_NUMBER (100) | |
29 | ||
a6d70980 | 30 | DEFINE_MUTEX(pm_mutex); |
1da177e4 | 31 | |
123d3c13 | 32 | struct pm_ops *pm_ops; |
1da177e4 LT |
33 | |
34 | /** | |
35 | * pm_set_ops - Set the global power method table. | |
36 | * @ops: Pointer to ops structure. | |
37 | */ | |
38 | ||
39 | void pm_set_ops(struct pm_ops * ops) | |
40 | { | |
a6d70980 | 41 | mutex_lock(&pm_mutex); |
1da177e4 | 42 | pm_ops = ops; |
a6d70980 | 43 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
44 | } |
45 | ||
e8c9c502 JB |
46 | /** |
47 | * pm_valid_only_mem - generic memory-only valid callback | |
48 | * | |
49 | * pm_ops drivers that implement mem suspend only and only need | |
50 | * to check for that in their .valid callback can use this instead | |
51 | * of rolling their own .valid callback. | |
52 | */ | |
53 | int pm_valid_only_mem(suspend_state_t state) | |
54 | { | |
55 | return state == PM_SUSPEND_MEM; | |
56 | } | |
57 | ||
58 | ||
e3c7db62 RW |
59 | static inline void pm_finish(suspend_state_t state) |
60 | { | |
61 | if (pm_ops->finish) | |
62 | pm_ops->finish(state); | |
63 | } | |
1da177e4 LT |
64 | |
65 | /** | |
66 | * suspend_prepare - Do prep work before entering low-power state. | |
67 | * @state: State we're entering. | |
68 | * | |
69 | * This is common code that is called for each state that we're | |
70 | * entering. Allocate a console, stop all processes, then make sure | |
71 | * the platform can enter the requested state. | |
72 | */ | |
73 | ||
74 | static int suspend_prepare(suspend_state_t state) | |
75 | { | |
e3920fb4 | 76 | int error; |
5ae947ec | 77 | unsigned int free_pages; |
1da177e4 LT |
78 | |
79 | if (!pm_ops || !pm_ops->enter) | |
80 | return -EPERM; | |
81 | ||
82 | pm_prepare_console(); | |
83 | ||
84 | if (freeze_processes()) { | |
85 | error = -EAGAIN; | |
86 | goto Thaw; | |
87 | } | |
88 | ||
96177299 CL |
89 | if ((free_pages = global_page_state(NR_FREE_PAGES)) |
90 | < FREE_PAGE_NUMBER) { | |
5ae947ec DSL |
91 | pr_debug("PM: free some memory\n"); |
92 | shrink_all_memory(FREE_PAGE_NUMBER - free_pages); | |
93 | if (nr_free_pages() < FREE_PAGE_NUMBER) { | |
94 | error = -ENOMEM; | |
95 | printk(KERN_ERR "PM: No enough memory\n"); | |
96 | goto Thaw; | |
97 | } | |
98 | } | |
99 | ||
1da177e4 LT |
100 | if (pm_ops->prepare) { |
101 | if ((error = pm_ops->prepare(state))) | |
102 | goto Thaw; | |
103 | } | |
104 | ||
557240b4 | 105 | suspend_console(); |
e3c7db62 RW |
106 | error = device_suspend(PMSG_SUSPEND); |
107 | if (error) { | |
1da177e4 | 108 | printk(KERN_ERR "Some devices failed to suspend\n"); |
e3c7db62 | 109 | goto Resume_devices; |
1da177e4 | 110 | } |
e3c7db62 RW |
111 | error = disable_nonboot_cpus(); |
112 | if (!error) | |
113 | return 0; | |
114 | ||
115 | enable_nonboot_cpus(); | |
116 | Resume_devices: | |
117 | pm_finish(state); | |
118 | device_resume(); | |
119 | resume_console(); | |
1da177e4 LT |
120 | Thaw: |
121 | thaw_processes(); | |
122 | pm_restore_console(); | |
123 | return error; | |
124 | } | |
125 | ||
a53c46dc JB |
126 | /* default implementation */ |
127 | void __attribute__ ((weak)) arch_suspend_disable_irqs(void) | |
128 | { | |
129 | local_irq_disable(); | |
130 | } | |
131 | ||
132 | /* default implementation */ | |
133 | void __attribute__ ((weak)) arch_suspend_enable_irqs(void) | |
134 | { | |
135 | local_irq_enable(); | |
136 | } | |
1da177e4 | 137 | |
9b238205 | 138 | int suspend_enter(suspend_state_t state) |
1da177e4 LT |
139 | { |
140 | int error = 0; | |
1da177e4 | 141 | |
a53c46dc JB |
142 | arch_suspend_disable_irqs(); |
143 | BUG_ON(!irqs_disabled()); | |
1da177e4 LT |
144 | |
145 | if ((error = device_power_down(PMSG_SUSPEND))) { | |
146 | printk(KERN_ERR "Some devices failed to power down\n"); | |
147 | goto Done; | |
148 | } | |
149 | error = pm_ops->enter(state); | |
150 | device_power_up(); | |
151 | Done: | |
a53c46dc JB |
152 | arch_suspend_enable_irqs(); |
153 | BUG_ON(irqs_disabled()); | |
1da177e4 LT |
154 | return error; |
155 | } | |
156 | ||
157 | ||
158 | /** | |
159 | * suspend_finish - Do final work before exiting suspend sequence. | |
160 | * @state: State we're coming out of. | |
161 | * | |
162 | * Call platform code to clean up, restart processes, and free the | |
163 | * console that we've allocated. This is not called for suspend-to-disk. | |
164 | */ | |
165 | ||
166 | static void suspend_finish(suspend_state_t state) | |
167 | { | |
e3c7db62 RW |
168 | enable_nonboot_cpus(); |
169 | pm_finish(state); | |
1da177e4 | 170 | device_resume(); |
557240b4 | 171 | resume_console(); |
1da177e4 LT |
172 | thaw_processes(); |
173 | pm_restore_console(); | |
174 | } | |
175 | ||
176 | ||
177 | ||
178 | ||
3b364b8d | 179 | static const char * const pm_states[PM_SUSPEND_MAX] = { |
1da177e4 LT |
180 | [PM_SUSPEND_STANDBY] = "standby", |
181 | [PM_SUSPEND_MEM] = "mem", | |
1da177e4 LT |
182 | }; |
183 | ||
123d3c13 PM |
184 | static inline int valid_state(suspend_state_t state) |
185 | { | |
a3d25c27 RW |
186 | /* All states need lowlevel support and need to be valid |
187 | * to the lowlevel implementation, no valid callback | |
9684e51c JB |
188 | * implies that none are valid. */ |
189 | if (!pm_ops || !pm_ops->valid || !pm_ops->valid(state)) | |
123d3c13 PM |
190 | return 0; |
191 | return 1; | |
192 | } | |
193 | ||
1da177e4 LT |
194 | |
195 | /** | |
196 | * enter_state - Do common work of entering low-power state. | |
197 | * @state: pm_state structure for state we're entering. | |
198 | * | |
199 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
200 | * if someone has beat us to it, since we don't want anything weird to | |
201 | * happen when we wake up. | |
202 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
203 | * we've woken up). | |
204 | */ | |
205 | ||
206 | static int enter_state(suspend_state_t state) | |
207 | { | |
208 | int error; | |
209 | ||
123d3c13 | 210 | if (!valid_state(state)) |
eb9289eb | 211 | return -ENODEV; |
a6d70980 | 212 | if (!mutex_trylock(&pm_mutex)) |
1da177e4 LT |
213 | return -EBUSY; |
214 | ||
82428b62 | 215 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
1da177e4 LT |
216 | if ((error = suspend_prepare(state))) |
217 | goto Unlock; | |
218 | ||
82428b62 | 219 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
1da177e4 LT |
220 | error = suspend_enter(state); |
221 | ||
82428b62 | 222 | pr_debug("PM: Finishing wakeup.\n"); |
1da177e4 LT |
223 | suspend_finish(state); |
224 | Unlock: | |
a6d70980 | 225 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
226 | return error; |
227 | } | |
228 | ||
1da177e4 LT |
229 | |
230 | /** | |
231 | * pm_suspend - Externally visible function for suspending system. | |
a3d25c27 | 232 | * @state: Enumerated value of state to enter. |
1da177e4 LT |
233 | * |
234 | * Determine whether or not value is within range, get state | |
235 | * structure, and enter (above). | |
236 | */ | |
237 | ||
238 | int pm_suspend(suspend_state_t state) | |
239 | { | |
e2a5b420 | 240 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
1da177e4 LT |
241 | return enter_state(state); |
242 | return -EINVAL; | |
243 | } | |
244 | ||
4cf30348 | 245 | EXPORT_SYMBOL(pm_suspend); |
1da177e4 LT |
246 | |
247 | decl_subsys(power,NULL,NULL); | |
248 | ||
249 | ||
250 | /** | |
251 | * state - control system power state. | |
252 | * | |
253 | * show() returns what states are supported, which is hard-coded to | |
254 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and | |
255 | * 'disk' (Suspend-to-Disk). | |
256 | * | |
257 | * store() accepts one of those strings, translates it into the | |
258 | * proper enumerated value, and initiates a suspend transition. | |
259 | */ | |
260 | ||
823bccfc | 261 | static ssize_t state_show(struct kset *kset, char *buf) |
1da177e4 LT |
262 | { |
263 | int i; | |
264 | char * s = buf; | |
265 | ||
266 | for (i = 0; i < PM_SUSPEND_MAX; i++) { | |
123d3c13 PM |
267 | if (pm_states[i] && valid_state(i)) |
268 | s += sprintf(s,"%s ", pm_states[i]); | |
1da177e4 | 269 | } |
a3d25c27 RW |
270 | #ifdef CONFIG_SOFTWARE_SUSPEND |
271 | s += sprintf(s, "%s\n", "disk"); | |
272 | #else | |
273 | if (s != buf) | |
274 | /* convert the last space to a newline */ | |
275 | *(s-1) = '\n'; | |
276 | #endif | |
1da177e4 LT |
277 | return (s - buf); |
278 | } | |
279 | ||
823bccfc | 280 | static ssize_t state_store(struct kset *kset, const char *buf, size_t n) |
1da177e4 LT |
281 | { |
282 | suspend_state_t state = PM_SUSPEND_STANDBY; | |
3b364b8d | 283 | const char * const *s; |
1da177e4 LT |
284 | char *p; |
285 | int error; | |
286 | int len; | |
287 | ||
288 | p = memchr(buf, '\n', n); | |
289 | len = p ? p - buf : n; | |
290 | ||
a3d25c27 RW |
291 | /* First, check if we are requested to hibernate */ |
292 | if (!strncmp(buf, "disk", len)) { | |
293 | error = hibernate(); | |
294 | return error ? error : n; | |
295 | } | |
296 | ||
1da177e4 LT |
297 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { |
298 | if (*s && !strncmp(buf, *s, len)) | |
299 | break; | |
300 | } | |
47bb7899 | 301 | if (state < PM_SUSPEND_MAX && *s) |
1da177e4 LT |
302 | error = enter_state(state); |
303 | else | |
304 | error = -EINVAL; | |
305 | return error ? error : n; | |
306 | } | |
307 | ||
308 | power_attr(state); | |
309 | ||
c5c6ba4e RW |
310 | #ifdef CONFIG_PM_TRACE |
311 | int pm_trace_enabled; | |
312 | ||
823bccfc | 313 | static ssize_t pm_trace_show(struct kset *kset, char *buf) |
c5c6ba4e RW |
314 | { |
315 | return sprintf(buf, "%d\n", pm_trace_enabled); | |
316 | } | |
317 | ||
318 | static ssize_t | |
823bccfc | 319 | pm_trace_store(struct kset *kset, const char *buf, size_t n) |
c5c6ba4e RW |
320 | { |
321 | int val; | |
322 | ||
323 | if (sscanf(buf, "%d", &val) == 1) { | |
324 | pm_trace_enabled = !!val; | |
325 | return n; | |
326 | } | |
327 | return -EINVAL; | |
328 | } | |
329 | ||
330 | power_attr(pm_trace); | |
331 | ||
332 | static struct attribute * g[] = { | |
333 | &state_attr.attr, | |
334 | &pm_trace_attr.attr, | |
335 | NULL, | |
336 | }; | |
337 | #else | |
1da177e4 LT |
338 | static struct attribute * g[] = { |
339 | &state_attr.attr, | |
340 | NULL, | |
341 | }; | |
c5c6ba4e | 342 | #endif /* CONFIG_PM_TRACE */ |
1da177e4 LT |
343 | |
344 | static struct attribute_group attr_group = { | |
345 | .attrs = g, | |
346 | }; | |
347 | ||
348 | ||
349 | static int __init pm_init(void) | |
350 | { | |
351 | int error = subsystem_register(&power_subsys); | |
352 | if (!error) | |
823bccfc | 353 | error = sysfs_create_group(&power_subsys.kobj,&attr_group); |
1da177e4 LT |
354 | return error; |
355 | } | |
356 | ||
357 | core_initcall(pm_init); |