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; |
fe0c935a | 33 | suspend_disk_method_t pm_disk_mode = PM_DISK_SHUTDOWN; |
1da177e4 LT |
34 | |
35 | /** | |
36 | * pm_set_ops - Set the global power method table. | |
37 | * @ops: Pointer to ops structure. | |
38 | */ | |
39 | ||
40 | void pm_set_ops(struct pm_ops * ops) | |
41 | { | |
a6d70980 | 42 | mutex_lock(&pm_mutex); |
1da177e4 | 43 | pm_ops = ops; |
fe0c935a JB |
44 | if (ops && ops->pm_disk_mode != PM_DISK_INVALID) { |
45 | pm_disk_mode = ops->pm_disk_mode; | |
46 | } else | |
47 | pm_disk_mode = PM_DISK_SHUTDOWN; | |
a6d70980 | 48 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
49 | } |
50 | ||
e8c9c502 JB |
51 | /** |
52 | * pm_valid_only_mem - generic memory-only valid callback | |
53 | * | |
54 | * pm_ops drivers that implement mem suspend only and only need | |
55 | * to check for that in their .valid callback can use this instead | |
56 | * of rolling their own .valid callback. | |
57 | */ | |
58 | int pm_valid_only_mem(suspend_state_t state) | |
59 | { | |
60 | return state == PM_SUSPEND_MEM; | |
61 | } | |
62 | ||
63 | ||
e3c7db62 RW |
64 | static inline void pm_finish(suspend_state_t state) |
65 | { | |
66 | if (pm_ops->finish) | |
67 | pm_ops->finish(state); | |
68 | } | |
1da177e4 LT |
69 | |
70 | /** | |
71 | * suspend_prepare - Do prep work before entering low-power state. | |
72 | * @state: State we're entering. | |
73 | * | |
74 | * This is common code that is called for each state that we're | |
75 | * entering. Allocate a console, stop all processes, then make sure | |
76 | * the platform can enter the requested state. | |
77 | */ | |
78 | ||
79 | static int suspend_prepare(suspend_state_t state) | |
80 | { | |
e3920fb4 | 81 | int error; |
5ae947ec | 82 | unsigned int free_pages; |
1da177e4 LT |
83 | |
84 | if (!pm_ops || !pm_ops->enter) | |
85 | return -EPERM; | |
86 | ||
87 | pm_prepare_console(); | |
88 | ||
89 | if (freeze_processes()) { | |
90 | error = -EAGAIN; | |
91 | goto Thaw; | |
92 | } | |
93 | ||
96177299 CL |
94 | if ((free_pages = global_page_state(NR_FREE_PAGES)) |
95 | < FREE_PAGE_NUMBER) { | |
5ae947ec DSL |
96 | pr_debug("PM: free some memory\n"); |
97 | shrink_all_memory(FREE_PAGE_NUMBER - free_pages); | |
98 | if (nr_free_pages() < FREE_PAGE_NUMBER) { | |
99 | error = -ENOMEM; | |
100 | printk(KERN_ERR "PM: No enough memory\n"); | |
101 | goto Thaw; | |
102 | } | |
103 | } | |
104 | ||
1da177e4 LT |
105 | if (pm_ops->prepare) { |
106 | if ((error = pm_ops->prepare(state))) | |
107 | goto Thaw; | |
108 | } | |
109 | ||
557240b4 | 110 | suspend_console(); |
e3c7db62 RW |
111 | error = device_suspend(PMSG_SUSPEND); |
112 | if (error) { | |
1da177e4 | 113 | printk(KERN_ERR "Some devices failed to suspend\n"); |
e3c7db62 | 114 | goto Resume_devices; |
1da177e4 | 115 | } |
e3c7db62 RW |
116 | error = disable_nonboot_cpus(); |
117 | if (!error) | |
118 | return 0; | |
119 | ||
120 | enable_nonboot_cpus(); | |
121 | Resume_devices: | |
122 | pm_finish(state); | |
123 | device_resume(); | |
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", | |
57c4ce3c | 187 | #ifdef CONFIG_SOFTWARE_SUSPEND |
1da177e4 | 188 | [PM_SUSPEND_DISK] = "disk", |
57c4ce3c | 189 | #endif |
1da177e4 LT |
190 | }; |
191 | ||
123d3c13 PM |
192 | static inline int valid_state(suspend_state_t state) |
193 | { | |
194 | /* Suspend-to-disk does not really need low-level support. | |
195 | * It can work with reboot if needed. */ | |
196 | if (state == PM_SUSPEND_DISK) | |
197 | return 1; | |
198 | ||
9c372d06 JB |
199 | /* all other states need lowlevel support and need to be |
200 | * valid to the lowlevel implementation, no valid callback | |
9684e51c JB |
201 | * implies that none are valid. */ |
202 | if (!pm_ops || !pm_ops->valid || !pm_ops->valid(state)) | |
123d3c13 PM |
203 | return 0; |
204 | return 1; | |
205 | } | |
206 | ||
1da177e4 LT |
207 | |
208 | /** | |
209 | * enter_state - Do common work of entering low-power state. | |
210 | * @state: pm_state structure for state we're entering. | |
211 | * | |
212 | * Make sure we're the only ones trying to enter a sleep state. Fail | |
213 | * if someone has beat us to it, since we don't want anything weird to | |
214 | * happen when we wake up. | |
215 | * Then, do the setup for suspend, enter the state, and cleaup (after | |
216 | * we've woken up). | |
217 | */ | |
218 | ||
219 | static int enter_state(suspend_state_t state) | |
220 | { | |
221 | int error; | |
222 | ||
123d3c13 | 223 | if (!valid_state(state)) |
eb9289eb | 224 | return -ENODEV; |
a6d70980 | 225 | if (!mutex_trylock(&pm_mutex)) |
1da177e4 LT |
226 | return -EBUSY; |
227 | ||
228 | if (state == PM_SUSPEND_DISK) { | |
229 | error = pm_suspend_disk(); | |
230 | goto Unlock; | |
231 | } | |
232 | ||
82428b62 | 233 | pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); |
1da177e4 LT |
234 | if ((error = suspend_prepare(state))) |
235 | goto Unlock; | |
236 | ||
82428b62 | 237 | pr_debug("PM: Entering %s sleep\n", pm_states[state]); |
1da177e4 LT |
238 | error = suspend_enter(state); |
239 | ||
82428b62 | 240 | pr_debug("PM: Finishing wakeup.\n"); |
1da177e4 LT |
241 | suspend_finish(state); |
242 | Unlock: | |
a6d70980 | 243 | mutex_unlock(&pm_mutex); |
1da177e4 LT |
244 | return error; |
245 | } | |
246 | ||
247 | /* | |
248 | * This is main interface to the outside world. It needs to be | |
249 | * called from process context. | |
250 | */ | |
251 | int software_suspend(void) | |
252 | { | |
253 | return enter_state(PM_SUSPEND_DISK); | |
254 | } | |
255 | ||
256 | ||
257 | /** | |
258 | * pm_suspend - Externally visible function for suspending system. | |
259 | * @state: Enumarted value of state to enter. | |
260 | * | |
261 | * Determine whether or not value is within range, get state | |
262 | * structure, and enter (above). | |
263 | */ | |
264 | ||
265 | int pm_suspend(suspend_state_t state) | |
266 | { | |
e2a5b420 | 267 | if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX) |
1da177e4 LT |
268 | return enter_state(state); |
269 | return -EINVAL; | |
270 | } | |
271 | ||
4cf30348 | 272 | EXPORT_SYMBOL(pm_suspend); |
1da177e4 LT |
273 | |
274 | decl_subsys(power,NULL,NULL); | |
275 | ||
276 | ||
277 | /** | |
278 | * state - control system power state. | |
279 | * | |
280 | * show() returns what states are supported, which is hard-coded to | |
281 | * 'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and | |
282 | * 'disk' (Suspend-to-Disk). | |
283 | * | |
284 | * store() accepts one of those strings, translates it into the | |
285 | * proper enumerated value, and initiates a suspend transition. | |
286 | */ | |
287 | ||
823bccfc | 288 | static ssize_t state_show(struct kset *kset, char *buf) |
1da177e4 LT |
289 | { |
290 | int i; | |
291 | char * s = buf; | |
292 | ||
293 | for (i = 0; i < PM_SUSPEND_MAX; i++) { | |
123d3c13 PM |
294 | if (pm_states[i] && valid_state(i)) |
295 | s += sprintf(s,"%s ", pm_states[i]); | |
1da177e4 LT |
296 | } |
297 | s += sprintf(s,"\n"); | |
298 | return (s - buf); | |
299 | } | |
300 | ||
823bccfc | 301 | static ssize_t state_store(struct kset *kset, const char *buf, size_t n) |
1da177e4 LT |
302 | { |
303 | suspend_state_t state = PM_SUSPEND_STANDBY; | |
3b364b8d | 304 | const char * const *s; |
1da177e4 LT |
305 | char *p; |
306 | int error; | |
307 | int len; | |
308 | ||
309 | p = memchr(buf, '\n', n); | |
310 | len = p ? p - buf : n; | |
311 | ||
312 | for (s = &pm_states[state]; state < PM_SUSPEND_MAX; s++, state++) { | |
313 | if (*s && !strncmp(buf, *s, len)) | |
314 | break; | |
315 | } | |
47bb7899 | 316 | if (state < PM_SUSPEND_MAX && *s) |
1da177e4 LT |
317 | error = enter_state(state); |
318 | else | |
319 | error = -EINVAL; | |
320 | return error ? error : n; | |
321 | } | |
322 | ||
323 | power_attr(state); | |
324 | ||
c5c6ba4e RW |
325 | #ifdef CONFIG_PM_TRACE |
326 | int pm_trace_enabled; | |
327 | ||
823bccfc | 328 | static ssize_t pm_trace_show(struct kset *kset, char *buf) |
c5c6ba4e RW |
329 | { |
330 | return sprintf(buf, "%d\n", pm_trace_enabled); | |
331 | } | |
332 | ||
333 | static ssize_t | |
823bccfc | 334 | pm_trace_store(struct kset *kset, const char *buf, size_t n) |
c5c6ba4e RW |
335 | { |
336 | int val; | |
337 | ||
338 | if (sscanf(buf, "%d", &val) == 1) { | |
339 | pm_trace_enabled = !!val; | |
340 | return n; | |
341 | } | |
342 | return -EINVAL; | |
343 | } | |
344 | ||
345 | power_attr(pm_trace); | |
346 | ||
347 | static struct attribute * g[] = { | |
348 | &state_attr.attr, | |
349 | &pm_trace_attr.attr, | |
350 | NULL, | |
351 | }; | |
352 | #else | |
1da177e4 LT |
353 | static struct attribute * g[] = { |
354 | &state_attr.attr, | |
355 | NULL, | |
356 | }; | |
c5c6ba4e | 357 | #endif /* CONFIG_PM_TRACE */ |
1da177e4 LT |
358 | |
359 | static struct attribute_group attr_group = { | |
360 | .attrs = g, | |
361 | }; | |
362 | ||
363 | ||
364 | static int __init pm_init(void) | |
365 | { | |
366 | int error = subsystem_register(&power_subsys); | |
367 | if (!error) | |
823bccfc | 368 | error = sysfs_create_group(&power_subsys.kobj,&attr_group); |
1da177e4 LT |
369 | return error; |
370 | } | |
371 | ||
372 | core_initcall(pm_init); |