1 /*
2 * pm.h - Power management interface
3 *
4 * Copyright (C) 2000 Andrew Henroid
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21 #ifndef _LINUX_PM_H
22 #define _LINUX_PM_H
23
24 #include <linux/list.h>
25 #include <linux/workqueue.h>
26 #include <linux/spinlock.h>
27 #include <linux/wait.h>
28 #include <linux/timer.h>
29 #include <linux/completion.h>
30
31 /*
32 * Callbacks for platform drivers to implement.
33 */
34 extern void (*pm_idle)(void);
35 extern void (*pm_power_off)(void);
36 extern void (*pm_power_off_prepare)(void);
37
38 /*
39 * Device power management
40 */
41
42 struct device;
43
44 #ifdef CONFIG_PM
45 extern const char power_group_name[]; /* = "power" */
46 #else
47 #define power_group_name NULL
48 #endif
49
50 typedef struct pm_message {
51 int event;
52 } pm_message_t;
53
54 /**
55 * struct dev_pm_ops - device PM callbacks
56 *
57 * Several device power state transitions are externally visible, affecting
58 * the state of pending I/O queues and (for drivers that touch hardware)
59 * interrupts, wakeups, DMA, and other hardware state. There may also be
60 * internal transitions to various low-power modes which are transparent
61 * to the rest of the driver stack (such as a driver that's ON gating off
62 * clocks which are not in active use).
63 *
64 * The externally visible transitions are handled with the help of callbacks
65 * included in this structure in such a way that two levels of callbacks are
66 * involved. First, the PM core executes callbacks provided by PM domains,
67 * device types, classes and bus types. They are the subsystem-level callbacks
68 * supposed to execute callbacks provided by device drivers, although they may
69 * choose not to do that. If the driver callbacks are executed, they have to
70 * collaborate with the subsystem-level callbacks to achieve the goals
71 * appropriate for the given system transition, given transition phase and the
72 * subsystem the device belongs to.
73 *
74 * @prepare: The principal role of this callback is to prevent new children of
75 * the device from being registered after it has returned (the driver's
76 * subsystem and generally the rest of the kernel is supposed to prevent
77 * new calls to the probe method from being made too once @prepare() has
78 * succeeded). If @prepare() detects a situation it cannot handle (e.g.
79 * registration of a child already in progress), it may return -EAGAIN, so
80 * that the PM core can execute it once again (e.g. after a new child has
81 * been registered) to recover from the race condition.
82 * This method is executed for all kinds of suspend transitions and is
83 * followed by one of the suspend callbacks: @suspend(), @freeze(), or
84 * @poweroff(). The PM core executes subsystem-level @prepare() for all
85 * devices before starting to invoke suspend callbacks for any of them, so
86 * generally devices may be assumed to be functional or to respond to
87 * runtime resume requests while @prepare() is being executed. However,
88 * device drivers may NOT assume anything about the availability of user
89 * space at that time and it is NOT valid to request firmware from within
90 * @prepare() (it's too late to do that). It also is NOT valid to allocate
91 * substantial amounts of memory from @prepare() in the GFP_KERNEL mode.
92 * [To work around these limitations, drivers may register suspend and
93 * hibernation notifiers to be executed before the freezing of tasks.]
94 *
95 * @complete: Undo the changes made by @prepare(). This method is executed for
96 * all kinds of resume transitions, following one of the resume callbacks:
97 * @resume(), @thaw(), @restore(). Also called if the state transition
98 * fails before the driver's suspend callback: @suspend(), @freeze() or
99 * @poweroff(), can be executed (e.g. if the suspend callback fails for one
100 * of the other devices that the PM core has unsuccessfully attempted to
101 * suspend earlier).
102 * The PM core executes subsystem-level @complete() after it has executed
103 * the appropriate resume callbacks for all devices.
104 *
105 * @suspend: Executed before putting the system into a sleep state in which the
106 * contents of main memory are preserved. The exact action to perform
107 * depends on the device's subsystem (PM domain, device type, class or bus
108 * type), but generally the device must be quiescent after subsystem-level
109 * @suspend() has returned, so that it doesn't do any I/O or DMA.
110 * Subsystem-level @suspend() is executed for all devices after invoking
111 * subsystem-level @prepare() for all of them.
112 *
113 * @suspend_late: Continue operations started by @suspend(). For a number of
114 * devices @suspend_late() may point to the same callback routine as the
115 * runtime suspend callback.
116 *
117 * @resume: Executed after waking the system up from a sleep state in which the
118 * contents of main memory were preserved. The exact action to perform
119 * depends on the device's subsystem, but generally the driver is expected
120 * to start working again, responding to hardware events and software
121 * requests (the device itself may be left in a low-power state, waiting
122 * for a runtime resume to occur). The state of the device at the time its
123 * driver's @resume() callback is run depends on the platform and subsystem
124 * the device belongs to. On most platforms, there are no restrictions on
125 * availability of resources like clocks during @resume().
126 * Subsystem-level @resume() is executed for all devices after invoking
127 * subsystem-level @resume_noirq() for all of them.
128 *
129 * @resume_early: Prepare to execute @resume(). For a number of devices
130 * @resume_early() may point to the same callback routine as the runtime
131 * resume callback.
132 *
133 * @freeze: Hibernation-specific, executed before creating a hibernation image.
134 * Analogous to @suspend(), but it should not enable the device to signal
135 * wakeup events or change its power state. The majority of subsystems
136 * (with the notable exception of the PCI bus type) expect the driver-level
137 * @freeze() to save the device settings in memory to be used by @restore()
138 * during the subsequent resume from hibernation.
139 * Subsystem-level @freeze() is executed for all devices after invoking
140 * subsystem-level @prepare() for all of them.
141 *
142 * @freeze_late: Continue operations started by @freeze(). Analogous to
143 * @suspend_late(), but it should not enable the device to signal wakeup
144 * events or change its power state.
145 *
146 * @thaw: Hibernation-specific, executed after creating a hibernation image OR
147 * if the creation of an image has failed. Also executed after a failing
148 * attempt to restore the contents of main memory from such an image.
149 * Undo the changes made by the preceding @freeze(), so the device can be
150 * operated in the same way as immediately before the call to @freeze().
151 * Subsystem-level @thaw() is executed for all devices after invoking
152 * subsystem-level @thaw_noirq() for all of them. It also may be executed
153 * directly after @freeze() in case of a transition error.
154 *
155 * @thaw_early: Prepare to execute @thaw(). Undo the changes made by the
156 * preceding @freeze_late().
157 *
158 * @poweroff: Hibernation-specific, executed after saving a hibernation image.
159 * Analogous to @suspend(), but it need not save the device's settings in
160 * memory.
161 * Subsystem-level @poweroff() is executed for all devices after invoking
162 * subsystem-level @prepare() for all of them.
163 *
164 * @poweroff_late: Continue operations started by @poweroff(). Analogous to
165 * @suspend_late(), but it need not save the device's settings in memory.
166 *
167 * @restore: Hibernation-specific, executed after restoring the contents of main
168 * memory from a hibernation image, analogous to @resume().
169 *
170 * @restore_early: Prepare to execute @restore(), analogous to @resume_early().
171 *
172 * @suspend_noirq: Complete the actions started by @suspend(). Carry out any
173 * additional operations required for suspending the device that might be
174 * racing with its driver's interrupt handler, which is guaranteed not to
175 * run while @suspend_noirq() is being executed.
176 * It generally is expected that the device will be in a low-power state
177 * (appropriate for the target system sleep state) after subsystem-level
178 * @suspend_noirq() has returned successfully. If the device can generate
179 * system wakeup signals and is enabled to wake up the system, it should be
180 * configured to do so at that time. However, depending on the platform
181 * and device's subsystem, @suspend() or @suspend_late() may be allowed to
182 * put the device into the low-power state and configure it to generate
183 * wakeup signals, in which case it generally is not necessary to define
184 * @suspend_noirq().
185 *
186 * @resume_noirq: Prepare for the execution of @resume() by carrying out any
187 * operations required for resuming the device that might be racing with
188 * its driver's interrupt handler, which is guaranteed not to run while
189 * @resume_noirq() is being executed.
190 *
191 * @freeze_noirq: Complete the actions started by @freeze(). Carry out any
192 * additional operations required for freezing the device that might be
193 * racing with its driver's interrupt handler, which is guaranteed not to
194 * run while @freeze_noirq() is being executed.
195 * The power state of the device should not be changed by either @freeze(),
196 * or @freeze_late(), or @freeze_noirq() and it should not be configured to
197 * signal system wakeup by any of these callbacks.
198 *
199 * @thaw_noirq: Prepare for the execution of @thaw() by carrying out any
200 * operations required for thawing the device that might be racing with its
201 * driver's interrupt handler, which is guaranteed not to run while
202 * @thaw_noirq() is being executed.
203 *
204 * @poweroff_noirq: Complete the actions started by @poweroff(). Analogous to
205 * @suspend_noirq(), but it need not save the device's settings in memory.
206 *
207 * @restore_noirq: Prepare for the execution of @restore() by carrying out any
208 * operations required for thawing the device that might be racing with its
209 * driver's interrupt handler, which is guaranteed not to run while
210 * @restore_noirq() is being executed. Analogous to @resume_noirq().
211 *
212 * All of the above callbacks, except for @complete(), return error codes.
213 * However, the error codes returned by the resume operations, @resume(),
214 * @thaw(), @restore(), @resume_noirq(), @thaw_noirq(), and @restore_noirq(), do
215 * not cause the PM core to abort the resume transition during which they are
216 * returned. The error codes returned in those cases are only printed by the PM
217 * core to the system logs for debugging purposes. Still, it is recommended
218 * that drivers only return error codes from their resume methods in case of an
219 * unrecoverable failure (i.e. when the device being handled refuses to resume
220 * and becomes unusable) to allow us to modify the PM core in the future, so
221 * that it can avoid attempting to handle devices that failed to resume and
222 * their children.
223 *
224 * It is allowed to unregister devices while the above callbacks are being
225 * executed. However, a callback routine must NOT try to unregister the device
226 * it was called for, although it may unregister children of that device (for
227 * example, if it detects that a child was unplugged while the system was
228 * asleep).
229 *
230 * Refer to Documentation/power/devices.txt for more information about the role
231 * of the above callbacks in the system suspend process.
232 *
233 * There also are callbacks related to runtime power management of devices.
234 * Again, these callbacks are executed by the PM core only for subsystems
235 * (PM domains, device types, classes and bus types) and the subsystem-level
236 * callbacks are supposed to invoke the driver callbacks. Moreover, the exact
237 * actions to be performed by a device driver's callbacks generally depend on
238 * the platform and subsystem the device belongs to.
239 *
240 * @runtime_suspend: Prepare the device for a condition in which it won't be
241 * able to communicate with the CPU(s) and RAM due to power management.
242 * This need not mean that the device should be put into a low-power state.
243 * For example, if the device is behind a link which is about to be turned
244 * off, the device may remain at full power. If the device does go to low
245 * power and is capable of generating runtime wakeup events, remote wakeup
246 * (i.e., a hardware mechanism allowing the device to request a change of
247 * its power state via an interrupt) should be enabled for it.
248 *
249 * @runtime_resume: Put the device into the fully active state in response to a
250 * wakeup event generated by hardware or at the request of software. If
251 * necessary, put the device into the full-power state and restore its
252 * registers, so that it is fully operational.
253 *
254 * @runtime_idle: Device appears to be inactive and it might be put into a
255 * low-power state if all of the necessary conditions are satisfied. Check
256 * these conditions and handle the device as appropriate, possibly queueing
257 * a suspend request for it. The return value is ignored by the PM core.
258 *
259 * Refer to Documentation/power/runtime_pm.txt for more information about the
260 * role of the above callbacks in device runtime power management.
261 *
262 */
263
264 struct dev_pm_ops {
265 int (*prepare)(struct device *dev);
266 void (*complete)(struct device *dev);
267 int (*suspend)(struct device *dev);
268 int (*resume)(struct device *dev);
269 int (*freeze)(struct device *dev);
270 int (*thaw)(struct device *dev);
271 int (*poweroff)(struct device *dev);
272 int (*restore)(struct device *dev);
273 int (*suspend_late)(struct device *dev);
274 int (*resume_early)(struct device *dev);
275 int (*freeze_late)(struct device *dev);
276 int (*thaw_early)(struct device *dev);
277 int (*poweroff_late)(struct device *dev);
278 int (*restore_early)(struct device *dev);
279 int (*suspend_noirq)(struct device *dev);
280 int (*resume_noirq)(struct device *dev);
281 int (*freeze_noirq)(struct device *dev);
282 int (*thaw_noirq)(struct device *dev);
283 int (*poweroff_noirq)(struct device *dev);
284 int (*restore_noirq)(struct device *dev);
285 int (*runtime_suspend)(struct device *dev);
286 int (*runtime_resume)(struct device *dev);
287 int (*runtime_idle)(struct device *dev);
288 };
289
290 #ifdef CONFIG_PM_SLEEP
291 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
292 .suspend = suspend_fn, \
293 .resume = resume_fn, \
294 .freeze = suspend_fn, \
295 .thaw = resume_fn, \
296 .poweroff = suspend_fn, \
297 .restore = resume_fn,
298 #else
299 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
300 #endif
301
302 #ifdef CONFIG_PM_RUNTIME
303 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
304 .runtime_suspend = suspend_fn, \
305 .runtime_resume = resume_fn, \
306 .runtime_idle = idle_fn,
307 #else
308 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
309 #endif
310
311 /*
312 * Use this if you want to use the same suspend and resume callbacks for suspend
313 * to RAM and hibernation.
314 */
315 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
316 const struct dev_pm_ops name = { \
317 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
318 }
319
320 /*
321 * Use this for defining a set of PM operations to be used in all situations
322 * (sustem suspend, hibernation or runtime PM).
323 * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
324 * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
325 * and .runtime_resume(), because .runtime_suspend() always works on an already
326 * quiescent device, while .suspend() should assume that the device may be doing
327 * something when it is called (it should ensure that the device will be
328 * quiescent after it has returned). Therefore it's better to point the "late"
329 * suspend and "early" resume callback pointers, .suspend_late() and
330 * .resume_early(), to the same routines as .runtime_suspend() and
331 * .runtime_resume(), respectively (and analogously for hibernation).
332 */
333 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
334 const struct dev_pm_ops name = { \
335 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
336 SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
337 }
338
339 /**
340 * PM_EVENT_ messages
341 *
342 * The following PM_EVENT_ messages are defined for the internal use of the PM
343 * core, in order to provide a mechanism allowing the high level suspend and
344 * hibernation code to convey the necessary information to the device PM core
345 * code:
346 *
347 * ON No transition.
348 *
349 * FREEZE System is going to hibernate, call ->prepare() and ->freeze()
350 * for all devices.
351 *
352 * SUSPEND System is going to suspend, call ->prepare() and ->suspend()
353 * for all devices.
354 *
355 * HIBERNATE Hibernation image has been saved, call ->prepare() and
356 * ->poweroff() for all devices.
357 *
358 * QUIESCE Contents of main memory are going to be restored from a (loaded)
359 * hibernation image, call ->prepare() and ->freeze() for all
360 * devices.
361 *
362 * RESUME System is resuming, call ->resume() and ->complete() for all
363 * devices.
364 *
365 * THAW Hibernation image has been created, call ->thaw() and
366 * ->complete() for all devices.
367 *
368 * RESTORE Contents of main memory have been restored from a hibernation
369 * image, call ->restore() and ->complete() for all devices.
370 *
371 * RECOVER Creation of a hibernation image or restoration of the main
372 * memory contents from a hibernation image has failed, call
373 * ->thaw() and ->complete() for all devices.
374 *
375 * The following PM_EVENT_ messages are defined for internal use by
376 * kernel subsystems. They are never issued by the PM core.
377 *
378 * USER_SUSPEND Manual selective suspend was issued by userspace.
379 *
380 * USER_RESUME Manual selective resume was issued by userspace.
381 *
382 * REMOTE_WAKEUP Remote-wakeup request was received from the device.
383 *
384 * AUTO_SUSPEND Automatic (device idle) runtime suspend was
385 * initiated by the subsystem.
386 *
387 * AUTO_RESUME Automatic (device needed) runtime resume was
388 * requested by a driver.
389 */
390
391 #define PM_EVENT_INVALID (-1)
392 #define PM_EVENT_ON 0x0000
393 #define PM_EVENT_FREEZE 0x0001
394 #define PM_EVENT_SUSPEND 0x0002
395 #define PM_EVENT_HIBERNATE 0x0004
396 #define PM_EVENT_QUIESCE 0x0008
397 #define PM_EVENT_RESUME 0x0010
398 #define PM_EVENT_THAW 0x0020
399 #define PM_EVENT_RESTORE 0x0040
400 #define PM_EVENT_RECOVER 0x0080
401 #define PM_EVENT_USER 0x0100
402 #define PM_EVENT_REMOTE 0x0200
403 #define PM_EVENT_AUTO 0x0400
404
405 #define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
406 #define PM_EVENT_USER_SUSPEND (PM_EVENT_USER | PM_EVENT_SUSPEND)
407 #define PM_EVENT_USER_RESUME (PM_EVENT_USER | PM_EVENT_RESUME)
408 #define PM_EVENT_REMOTE_RESUME (PM_EVENT_REMOTE | PM_EVENT_RESUME)
409 #define PM_EVENT_AUTO_SUSPEND (PM_EVENT_AUTO | PM_EVENT_SUSPEND)
410 #define PM_EVENT_AUTO_RESUME (PM_EVENT_AUTO | PM_EVENT_RESUME)
411
412 #define PMSG_INVALID ((struct pm_message){ .event = PM_EVENT_INVALID, })
413 #define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, })
414 #define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, })
415 #define PMSG_QUIESCE ((struct pm_message){ .event = PM_EVENT_QUIESCE, })
416 #define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
417 #define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
418 #define PMSG_RESUME ((struct pm_message){ .event = PM_EVENT_RESUME, })
419 #define PMSG_THAW ((struct pm_message){ .event = PM_EVENT_THAW, })
420 #define PMSG_RESTORE ((struct pm_message){ .event = PM_EVENT_RESTORE, })
421 #define PMSG_RECOVER ((struct pm_message){ .event = PM_EVENT_RECOVER, })
422 #define PMSG_USER_SUSPEND ((struct pm_message) \
423 { .event = PM_EVENT_USER_SUSPEND, })
424 #define PMSG_USER_RESUME ((struct pm_message) \
425 { .event = PM_EVENT_USER_RESUME, })
426 #define PMSG_REMOTE_RESUME ((struct pm_message) \
427 { .event = PM_EVENT_REMOTE_RESUME, })
428 #define PMSG_AUTO_SUSPEND ((struct pm_message) \
429 { .event = PM_EVENT_AUTO_SUSPEND, })
430 #define PMSG_AUTO_RESUME ((struct pm_message) \
431 { .event = PM_EVENT_AUTO_RESUME, })
432
433 #define PMSG_IS_AUTO(msg) (((msg).event & PM_EVENT_AUTO) != 0)
434
435 /**
436 * Device run-time power management status.
437 *
438 * These status labels are used internally by the PM core to indicate the
439 * current status of a device with respect to the PM core operations. They do
440 * not reflect the actual power state of the device or its status as seen by the
441 * driver.
442 *
443 * RPM_ACTIVE Device is fully operational. Indicates that the device
444 * bus type's ->runtime_resume() callback has completed
445 * successfully.
446 *
447 * RPM_SUSPENDED Device bus type's ->runtime_suspend() callback has
448 * completed successfully. The device is regarded as
449 * suspended.
450 *
451 * RPM_RESUMING Device bus type's ->runtime_resume() callback is being
452 * executed.
453 *
454 * RPM_SUSPENDING Device bus type's ->runtime_suspend() callback is being
455 * executed.
456 */
457
458 enum rpm_status {
459 RPM_ACTIVE = 0,
460 RPM_RESUMING,
461 RPM_SUSPENDED,
462 RPM_SUSPENDING,
463 };
464
465 /**
466 * Device run-time power management request types.
467 *
468 * RPM_REQ_NONE Do nothing.
469 *
470 * RPM_REQ_IDLE Run the device bus type's ->runtime_idle() callback
471 *
472 * RPM_REQ_SUSPEND Run the device bus type's ->runtime_suspend() callback
473 *
474 * RPM_REQ_AUTOSUSPEND Same as RPM_REQ_SUSPEND, but not until the device has
475 * been inactive for as long as power.autosuspend_delay
476 *
477 * RPM_REQ_RESUME Run the device bus type's ->runtime_resume() callback
478 */
479
480 enum rpm_request {
481 RPM_REQ_NONE = 0,
482 RPM_REQ_IDLE,
483 RPM_REQ_SUSPEND,
484 RPM_REQ_AUTOSUSPEND,
485 RPM_REQ_RESUME,
486 };
487
488 struct wakeup_source;
489
490 struct pm_domain_data {
491 struct list_head list_node;
492 struct device *dev;
493 };
494
495 struct pm_subsys_data {
496 spinlock_t lock;
497 unsigned int refcount;
498 #ifdef CONFIG_PM_CLK
499 struct list_head clock_list;
500 #endif
501 #ifdef CONFIG_PM_GENERIC_DOMAINS
502 struct pm_domain_data *domain_data;
503 #endif
504 };
505
506 struct dev_pm_info {
507 pm_message_t power_state;
508 unsigned int can_wakeup:1;
509 unsigned int async_suspend:1;
510 bool is_prepared:1; /* Owned by the PM core */
511 bool is_suspended:1; /* Ditto */
512 bool ignore_children:1;
513 spinlock_t lock;
514 #ifdef CONFIG_PM_SLEEP
515 struct list_head entry;
516 struct completion completion;
517 struct wakeup_source *wakeup;
518 bool wakeup_path:1;
519 #else
520 unsigned int should_wakeup:1;
521 #endif
522 #ifdef CONFIG_PM_RUNTIME
523 struct timer_list suspend_timer;
524 unsigned long timer_expires;
525 struct work_struct work;
526 wait_queue_head_t wait_queue;
527 atomic_t usage_count;
528 atomic_t child_count;
529 unsigned int disable_depth:3;
530 unsigned int idle_notification:1;
531 unsigned int request_pending:1;
532 unsigned int deferred_resume:1;
533 unsigned int run_wake:1;
534 unsigned int runtime_auto:1;
535 unsigned int no_callbacks:1;
536 unsigned int irq_safe:1;
537 unsigned int use_autosuspend:1;
538 unsigned int timer_autosuspends:1;
539 enum rpm_request request;
540 enum rpm_status runtime_status;
541 int runtime_error;
542 int autosuspend_delay;
543 unsigned long last_busy;
544 unsigned long active_jiffies;
545 unsigned long suspended_jiffies;
546 unsigned long accounting_timestamp;
547 struct dev_pm_qos_request *pq_req;
548 #endif
549 struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */
550 struct pm_qos_constraints *constraints;
551 };
552
553 extern void update_pm_runtime_accounting(struct device *dev);
554 extern int dev_pm_get_subsys_data(struct device *dev);
555 extern int dev_pm_put_subsys_data(struct device *dev);
556
557 /*
558 * Power domains provide callbacks that are executed during system suspend,
559 * hibernation, system resume and during runtime PM transitions along with
560 * subsystem-level and driver-level callbacks.
561 */
562 struct dev_pm_domain {
563 struct dev_pm_ops ops;
564 };
565
566 /*
567 * The PM_EVENT_ messages are also used by drivers implementing the legacy
568 * suspend framework, based on the ->suspend() and ->resume() callbacks common
569 * for suspend and hibernation transitions, according to the rules below.
570 */
571
572 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
573 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
574
575 /*
576 * One transition is triggered by resume(), after a suspend() call; the
577 * message is implicit:
578 *
579 * ON Driver starts working again, responding to hardware events
580 * and software requests. The hardware may have gone through
581 * a power-off reset, or it may have maintained state from the
582 * previous suspend() which the driver will rely on while
583 * resuming. On most platforms, there are no restrictions on
584 * availability of resources like clocks during resume().
585 *
586 * Other transitions are triggered by messages sent using suspend(). All
587 * these transitions quiesce the driver, so that I/O queues are inactive.
588 * That commonly entails turning off IRQs and DMA; there may be rules
589 * about how to quiesce that are specific to the bus or the device's type.
590 * (For example, network drivers mark the link state.) Other details may
591 * differ according to the message:
592 *
593 * SUSPEND Quiesce, enter a low power device state appropriate for
594 * the upcoming system state (such as PCI_D3hot), and enable
595 * wakeup events as appropriate.
596 *
597 * HIBERNATE Enter a low power device state appropriate for the hibernation
598 * state (eg. ACPI S4) and enable wakeup events as appropriate.
599 *
600 * FREEZE Quiesce operations so that a consistent image can be saved;
601 * but do NOT otherwise enter a low power device state, and do
602 * NOT emit system wakeup events.
603 *
604 * PRETHAW Quiesce as if for FREEZE; additionally, prepare for restoring
605 * the system from a snapshot taken after an earlier FREEZE.
606 * Some drivers will need to reset their hardware state instead
607 * of preserving it, to ensure that it's never mistaken for the
608 * state which that earlier snapshot had set up.
609 *
610 * A minimally power-aware driver treats all messages as SUSPEND, fully
611 * reinitializes its device during resume() -- whether or not it was reset
612 * during the suspend/resume cycle -- and can't issue wakeup events.
613 *
614 * More power-aware drivers may also use low power states at runtime as
615 * well as during system sleep states like PM_SUSPEND_STANDBY. They may
616 * be able to use wakeup events to exit from runtime low-power states,
617 * or from system low-power states such as standby or suspend-to-RAM.
618 */
619
620 #ifdef CONFIG_PM_SLEEP
621 extern void device_pm_lock(void);
622 extern void dpm_resume_start(pm_message_t state);
623 extern void dpm_resume_end(pm_message_t state);
624 extern void dpm_resume(pm_message_t state);
625 extern void dpm_complete(pm_message_t state);
626
627 extern void device_pm_unlock(void);
628 extern int dpm_suspend_end(pm_message_t state);
629 extern int dpm_suspend_start(pm_message_t state);
630 extern int dpm_suspend(pm_message_t state);
631 extern int dpm_prepare(pm_message_t state);
632
633 extern void __suspend_report_result(const char *function, void *fn, int ret);
634
635 #define suspend_report_result(fn, ret) \
636 do { \
637 __suspend_report_result(__func__, fn, ret); \
638 } while (0)
639
640 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
641
642 extern int pm_generic_prepare(struct device *dev);
643 extern int pm_generic_suspend_late(struct device *dev);
644 extern int pm_generic_suspend_noirq(struct device *dev);
645 extern int pm_generic_suspend(struct device *dev);
646 extern int pm_generic_resume_early(struct device *dev);
647 extern int pm_generic_resume_noirq(struct device *dev);
648 extern int pm_generic_resume(struct device *dev);
649 extern int pm_generic_freeze_noirq(struct device *dev);
650 extern int pm_generic_freeze_late(struct device *dev);
651 extern int pm_generic_freeze(struct device *dev);
652 extern int pm_generic_thaw_noirq(struct device *dev);
653 extern int pm_generic_thaw_early(struct device *dev);
654 extern int pm_generic_thaw(struct device *dev);
655 extern int pm_generic_restore_noirq(struct device *dev);
656 extern int pm_generic_restore_early(struct device *dev);
657 extern int pm_generic_restore(struct device *dev);
658 extern int pm_generic_poweroff_noirq(struct device *dev);
659 extern int pm_generic_poweroff_late(struct device *dev);
660 extern int pm_generic_poweroff(struct device *dev);
661 extern void pm_generic_complete(struct device *dev);
662
663 #else /* !CONFIG_PM_SLEEP */
664
665 #define device_pm_lock() do {} while (0)
666 #define device_pm_unlock() do {} while (0)
667
dpm_suspend_start(pm_message_t state)668 static inline int dpm_suspend_start(pm_message_t state)
669 {
670 return 0;
671 }
672
673 #define suspend_report_result(fn, ret) do {} while (0)
674
device_pm_wait_for_dev(struct device * a,struct device * b)675 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
676 {
677 return 0;
678 }
679
680 #define pm_generic_prepare NULL
681 #define pm_generic_suspend NULL
682 #define pm_generic_resume NULL
683 #define pm_generic_freeze NULL
684 #define pm_generic_thaw NULL
685 #define pm_generic_restore NULL
686 #define pm_generic_poweroff NULL
687 #define pm_generic_complete NULL
688 #endif /* !CONFIG_PM_SLEEP */
689
690 /* How to reorder dpm_list after device_move() */
691 enum dpm_order {
692 DPM_ORDER_NONE,
693 DPM_ORDER_DEV_AFTER_PARENT,
694 DPM_ORDER_PARENT_BEFORE_DEV,
695 DPM_ORDER_DEV_LAST,
696 };
697
698 #endif /* _LINUX_PM_H */
699