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_power_off)(void);
35 extern void (*pm_power_off_prepare)(void);
36
37 struct device; /* we have a circular dep with device.h */
38 #ifdef CONFIG_VT_CONSOLE_SLEEP
39 extern void pm_vt_switch_required(struct device *dev, bool required);
40 extern void pm_vt_switch_unregister(struct device *dev);
41 #else
pm_vt_switch_required(struct device * dev,bool required)42 static inline void pm_vt_switch_required(struct device *dev, bool required)
43 {
44 }
pm_vt_switch_unregister(struct device * dev)45 static inline void pm_vt_switch_unregister(struct device *dev)
46 {
47 }
48 #endif /* CONFIG_VT_CONSOLE_SLEEP */
49
50 /*
51 * Device power management
52 */
53
54 struct device;
55
56 #ifdef CONFIG_PM
57 extern const char power_group_name[]; /* = "power" */
58 #else
59 #define power_group_name NULL
60 #endif
61
62 typedef struct pm_message {
63 int event;
64 } pm_message_t;
65
66 /**
67 * struct dev_pm_ops - device PM callbacks.
68 *
69 * @prepare: The principal role of this callback is to prevent new children of
70 * the device from being registered after it has returned (the driver's
71 * subsystem and generally the rest of the kernel is supposed to prevent
72 * new calls to the probe method from being made too once @prepare() has
73 * succeeded). If @prepare() detects a situation it cannot handle (e.g.
74 * registration of a child already in progress), it may return -EAGAIN, so
75 * that the PM core can execute it once again (e.g. after a new child has
76 * been registered) to recover from the race condition.
77 * This method is executed for all kinds of suspend transitions and is
78 * followed by one of the suspend callbacks: @suspend(), @freeze(), or
79 * @poweroff(). If the transition is a suspend to memory or standby (that
80 * is, not related to hibernation), the return value of @prepare() may be
81 * used to indicate to the PM core to leave the device in runtime suspend
82 * if applicable. Namely, if @prepare() returns a positive number, the PM
83 * core will understand that as a declaration that the device appears to be
84 * runtime-suspended and it may be left in that state during the entire
85 * transition and during the subsequent resume if all of its descendants
86 * are left in runtime suspend too. If that happens, @complete() will be
87 * executed directly after @prepare() and it must ensure the proper
88 * functioning of the device after the system resume.
89 * The PM core executes subsystem-level @prepare() for all devices before
90 * starting to invoke suspend callbacks for any of them, so generally
91 * devices may be assumed to be functional or to respond to runtime resume
92 * requests while @prepare() is being executed. However, device drivers
93 * may NOT assume anything about the availability of user space at that
94 * time and it is NOT valid to request firmware from within @prepare()
95 * (it's too late to do that). It also is NOT valid to allocate
96 * substantial amounts of memory from @prepare() in the GFP_KERNEL mode.
97 * [To work around these limitations, drivers may register suspend and
98 * hibernation notifiers to be executed before the freezing of tasks.]
99 *
100 * @complete: Undo the changes made by @prepare(). This method is executed for
101 * all kinds of resume transitions, following one of the resume callbacks:
102 * @resume(), @thaw(), @restore(). Also called if the state transition
103 * fails before the driver's suspend callback: @suspend(), @freeze() or
104 * @poweroff(), can be executed (e.g. if the suspend callback fails for one
105 * of the other devices that the PM core has unsuccessfully attempted to
106 * suspend earlier).
107 * The PM core executes subsystem-level @complete() after it has executed
108 * the appropriate resume callbacks for all devices. If the corresponding
109 * @prepare() at the beginning of the suspend transition returned a
110 * positive number and the device was left in runtime suspend (without
111 * executing any suspend and resume callbacks for it), @complete() will be
112 * the only callback executed for the device during resume. In that case,
113 * @complete() must be prepared to do whatever is necessary to ensure the
114 * proper functioning of the device after the system resume. To this end,
115 * @complete() can check the power.direct_complete flag of the device to
116 * learn whether (unset) or not (set) the previous suspend and resume
117 * callbacks have been executed for it.
118 *
119 * @suspend: Executed before putting the system into a sleep state in which the
120 * contents of main memory are preserved. The exact action to perform
121 * depends on the device's subsystem (PM domain, device type, class or bus
122 * type), but generally the device must be quiescent after subsystem-level
123 * @suspend() has returned, so that it doesn't do any I/O or DMA.
124 * Subsystem-level @suspend() is executed for all devices after invoking
125 * subsystem-level @prepare() for all of them.
126 *
127 * @suspend_late: Continue operations started by @suspend(). For a number of
128 * devices @suspend_late() may point to the same callback routine as the
129 * runtime suspend callback.
130 *
131 * @resume: Executed after waking the system up from a sleep state in which the
132 * contents of main memory were preserved. The exact action to perform
133 * depends on the device's subsystem, but generally the driver is expected
134 * to start working again, responding to hardware events and software
135 * requests (the device itself may be left in a low-power state, waiting
136 * for a runtime resume to occur). The state of the device at the time its
137 * driver's @resume() callback is run depends on the platform and subsystem
138 * the device belongs to. On most platforms, there are no restrictions on
139 * availability of resources like clocks during @resume().
140 * Subsystem-level @resume() is executed for all devices after invoking
141 * subsystem-level @resume_noirq() for all of them.
142 *
143 * @resume_early: Prepare to execute @resume(). For a number of devices
144 * @resume_early() may point to the same callback routine as the runtime
145 * resume callback.
146 *
147 * @freeze: Hibernation-specific, executed before creating a hibernation image.
148 * Analogous to @suspend(), but it should not enable the device to signal
149 * wakeup events or change its power state. The majority of subsystems
150 * (with the notable exception of the PCI bus type) expect the driver-level
151 * @freeze() to save the device settings in memory to be used by @restore()
152 * during the subsequent resume from hibernation.
153 * Subsystem-level @freeze() is executed for all devices after invoking
154 * subsystem-level @prepare() for all of them.
155 *
156 * @freeze_late: Continue operations started by @freeze(). Analogous to
157 * @suspend_late(), but it should not enable the device to signal wakeup
158 * events or change its power state.
159 *
160 * @thaw: Hibernation-specific, executed after creating a hibernation image OR
161 * if the creation of an image has failed. Also executed after a failing
162 * attempt to restore the contents of main memory from such an image.
163 * Undo the changes made by the preceding @freeze(), so the device can be
164 * operated in the same way as immediately before the call to @freeze().
165 * Subsystem-level @thaw() is executed for all devices after invoking
166 * subsystem-level @thaw_noirq() for all of them. It also may be executed
167 * directly after @freeze() in case of a transition error.
168 *
169 * @thaw_early: Prepare to execute @thaw(). Undo the changes made by the
170 * preceding @freeze_late().
171 *
172 * @poweroff: Hibernation-specific, executed after saving a hibernation image.
173 * Analogous to @suspend(), but it need not save the device's settings in
174 * memory.
175 * Subsystem-level @poweroff() is executed for all devices after invoking
176 * subsystem-level @prepare() for all of them.
177 *
178 * @poweroff_late: Continue operations started by @poweroff(). Analogous to
179 * @suspend_late(), but it need not save the device's settings in memory.
180 *
181 * @restore: Hibernation-specific, executed after restoring the contents of main
182 * memory from a hibernation image, analogous to @resume().
183 *
184 * @restore_early: Prepare to execute @restore(), analogous to @resume_early().
185 *
186 * @suspend_noirq: Complete the actions started by @suspend(). Carry out any
187 * additional operations required for suspending the device that might be
188 * racing with its driver's interrupt handler, which is guaranteed not to
189 * run while @suspend_noirq() is being executed.
190 * It generally is expected that the device will be in a low-power state
191 * (appropriate for the target system sleep state) after subsystem-level
192 * @suspend_noirq() has returned successfully. If the device can generate
193 * system wakeup signals and is enabled to wake up the system, it should be
194 * configured to do so at that time. However, depending on the platform
195 * and device's subsystem, @suspend() or @suspend_late() may be allowed to
196 * put the device into the low-power state and configure it to generate
197 * wakeup signals, in which case it generally is not necessary to define
198 * @suspend_noirq().
199 *
200 * @resume_noirq: Prepare for the execution of @resume() by carrying out any
201 * operations required for resuming the device that might be racing with
202 * its driver's interrupt handler, which is guaranteed not to run while
203 * @resume_noirq() is being executed.
204 *
205 * @freeze_noirq: Complete the actions started by @freeze(). Carry out any
206 * additional operations required for freezing the device that might be
207 * racing with its driver's interrupt handler, which is guaranteed not to
208 * run while @freeze_noirq() is being executed.
209 * The power state of the device should not be changed by either @freeze(),
210 * or @freeze_late(), or @freeze_noirq() and it should not be configured to
211 * signal system wakeup by any of these callbacks.
212 *
213 * @thaw_noirq: Prepare for the execution of @thaw() by carrying out any
214 * operations required for thawing the device that might be racing with its
215 * driver's interrupt handler, which is guaranteed not to run while
216 * @thaw_noirq() is being executed.
217 *
218 * @poweroff_noirq: Complete the actions started by @poweroff(). Analogous to
219 * @suspend_noirq(), but it need not save the device's settings in memory.
220 *
221 * @restore_noirq: Prepare for the execution of @restore() by carrying out any
222 * operations required for thawing the device that might be racing with its
223 * driver's interrupt handler, which is guaranteed not to run while
224 * @restore_noirq() is being executed. Analogous to @resume_noirq().
225 *
226 * @runtime_suspend: Prepare the device for a condition in which it won't be
227 * able to communicate with the CPU(s) and RAM due to power management.
228 * This need not mean that the device should be put into a low-power state.
229 * For example, if the device is behind a link which is about to be turned
230 * off, the device may remain at full power. If the device does go to low
231 * power and is capable of generating runtime wakeup events, remote wakeup
232 * (i.e., a hardware mechanism allowing the device to request a change of
233 * its power state via an interrupt) should be enabled for it.
234 *
235 * @runtime_resume: Put the device into the fully active state in response to a
236 * wakeup event generated by hardware or at the request of software. If
237 * necessary, put the device into the full-power state and restore its
238 * registers, so that it is fully operational.
239 *
240 * @runtime_idle: Device appears to be inactive and it might be put into a
241 * low-power state if all of the necessary conditions are satisfied.
242 * Check these conditions, and return 0 if it's appropriate to let the PM
243 * core queue a suspend request for the device.
244 *
245 * Several device power state transitions are externally visible, affecting
246 * the state of pending I/O queues and (for drivers that touch hardware)
247 * interrupts, wakeups, DMA, and other hardware state. There may also be
248 * internal transitions to various low-power modes which are transparent
249 * to the rest of the driver stack (such as a driver that's ON gating off
250 * clocks which are not in active use).
251 *
252 * The externally visible transitions are handled with the help of callbacks
253 * included in this structure in such a way that, typically, two levels of
254 * callbacks are involved. First, the PM core executes callbacks provided by PM
255 * domains, device types, classes and bus types. They are the subsystem-level
256 * callbacks expected to execute callbacks provided by device drivers, although
257 * they may choose not to do that. If the driver callbacks are executed, they
258 * have to collaborate with the subsystem-level callbacks to achieve the goals
259 * appropriate for the given system transition, given transition phase and the
260 * subsystem the device belongs to.
261 *
262 * All of the above callbacks, except for @complete(), return error codes.
263 * However, the error codes returned by @resume(), @thaw(), @restore(),
264 * @resume_noirq(), @thaw_noirq(), and @restore_noirq(), do not cause the PM
265 * core to abort the resume transition during which they are returned. The
266 * error codes returned in those cases are only printed to the system logs for
267 * debugging purposes. Still, it is recommended that drivers only return error
268 * codes from their resume methods in case of an unrecoverable failure (i.e.
269 * when the device being handled refuses to resume and becomes unusable) to
270 * allow the PM core to be modified in the future, so that it can avoid
271 * attempting to handle devices that failed to resume and their children.
272 *
273 * It is allowed to unregister devices while the above callbacks are being
274 * executed. However, a callback routine MUST NOT try to unregister the device
275 * it was called for, although it may unregister children of that device (for
276 * example, if it detects that a child was unplugged while the system was
277 * asleep).
278 *
279 * There also are callbacks related to runtime power management of devices.
280 * Again, as a rule these callbacks are executed by the PM core for subsystems
281 * (PM domains, device types, classes and bus types) and the subsystem-level
282 * callbacks are expected to invoke the driver callbacks. Moreover, the exact
283 * actions to be performed by a device driver's callbacks generally depend on
284 * the platform and subsystem the device belongs to.
285 *
286 * Refer to Documentation/power/runtime_pm.txt for more information about the
287 * role of the @runtime_suspend(), @runtime_resume() and @runtime_idle()
288 * callbacks in device runtime power management.
289 */
290 struct dev_pm_ops {
291 int (*prepare)(struct device *dev);
292 void (*complete)(struct device *dev);
293 int (*suspend)(struct device *dev);
294 int (*resume)(struct device *dev);
295 int (*freeze)(struct device *dev);
296 int (*thaw)(struct device *dev);
297 int (*poweroff)(struct device *dev);
298 int (*restore)(struct device *dev);
299 int (*suspend_late)(struct device *dev);
300 int (*resume_early)(struct device *dev);
301 int (*freeze_late)(struct device *dev);
302 int (*thaw_early)(struct device *dev);
303 int (*poweroff_late)(struct device *dev);
304 int (*restore_early)(struct device *dev);
305 int (*suspend_noirq)(struct device *dev);
306 int (*resume_noirq)(struct device *dev);
307 int (*freeze_noirq)(struct device *dev);
308 int (*thaw_noirq)(struct device *dev);
309 int (*poweroff_noirq)(struct device *dev);
310 int (*restore_noirq)(struct device *dev);
311 int (*runtime_suspend)(struct device *dev);
312 int (*runtime_resume)(struct device *dev);
313 int (*runtime_idle)(struct device *dev);
314 };
315
316 #ifdef CONFIG_PM_SLEEP
317 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
318 .suspend = suspend_fn, \
319 .resume = resume_fn, \
320 .freeze = suspend_fn, \
321 .thaw = resume_fn, \
322 .poweroff = suspend_fn, \
323 .restore = resume_fn,
324 #else
325 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
326 #endif
327
328 #ifdef CONFIG_PM_SLEEP
329 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
330 .suspend_late = suspend_fn, \
331 .resume_early = resume_fn, \
332 .freeze_late = suspend_fn, \
333 .thaw_early = resume_fn, \
334 .poweroff_late = suspend_fn, \
335 .restore_early = resume_fn,
336 #else
337 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
338 #endif
339
340 #ifdef CONFIG_PM_SLEEP
341 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
342 .suspend_noirq = suspend_fn, \
343 .resume_noirq = resume_fn, \
344 .freeze_noirq = suspend_fn, \
345 .thaw_noirq = resume_fn, \
346 .poweroff_noirq = suspend_fn, \
347 .restore_noirq = resume_fn,
348 #else
349 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
350 #endif
351
352 #ifdef CONFIG_PM
353 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
354 .runtime_suspend = suspend_fn, \
355 .runtime_resume = resume_fn, \
356 .runtime_idle = idle_fn,
357 #else
358 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
359 #endif
360
361 /*
362 * Use this if you want to use the same suspend and resume callbacks for suspend
363 * to RAM and hibernation.
364 */
365 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
366 const struct dev_pm_ops name = { \
367 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
368 }
369
370 /*
371 * Use this for defining a set of PM operations to be used in all situations
372 * (system suspend, hibernation or runtime PM).
373 * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
374 * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
375 * and .runtime_resume(), because .runtime_suspend() always works on an already
376 * quiescent device, while .suspend() should assume that the device may be doing
377 * something when it is called (it should ensure that the device will be
378 * quiescent after it has returned). Therefore it's better to point the "late"
379 * suspend and "early" resume callback pointers, .suspend_late() and
380 * .resume_early(), to the same routines as .runtime_suspend() and
381 * .runtime_resume(), respectively (and analogously for hibernation).
382 */
383 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
384 const struct dev_pm_ops name = { \
385 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
386 SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
387 }
388
389 /*
390 * PM_EVENT_ messages
391 *
392 * The following PM_EVENT_ messages are defined for the internal use of the PM
393 * core, in order to provide a mechanism allowing the high level suspend and
394 * hibernation code to convey the necessary information to the device PM core
395 * code:
396 *
397 * ON No transition.
398 *
399 * FREEZE System is going to hibernate, call ->prepare() and ->freeze()
400 * for all devices.
401 *
402 * SUSPEND System is going to suspend, call ->prepare() and ->suspend()
403 * for all devices.
404 *
405 * HIBERNATE Hibernation image has been saved, call ->prepare() and
406 * ->poweroff() for all devices.
407 *
408 * QUIESCE Contents of main memory are going to be restored from a (loaded)
409 * hibernation image, call ->prepare() and ->freeze() for all
410 * devices.
411 *
412 * RESUME System is resuming, call ->resume() and ->complete() for all
413 * devices.
414 *
415 * THAW Hibernation image has been created, call ->thaw() and
416 * ->complete() for all devices.
417 *
418 * RESTORE Contents of main memory have been restored from a hibernation
419 * image, call ->restore() and ->complete() for all devices.
420 *
421 * RECOVER Creation of a hibernation image or restoration of the main
422 * memory contents from a hibernation image has failed, call
423 * ->thaw() and ->complete() for all devices.
424 *
425 * The following PM_EVENT_ messages are defined for internal use by
426 * kernel subsystems. They are never issued by the PM core.
427 *
428 * USER_SUSPEND Manual selective suspend was issued by userspace.
429 *
430 * USER_RESUME Manual selective resume was issued by userspace.
431 *
432 * REMOTE_WAKEUP Remote-wakeup request was received from the device.
433 *
434 * AUTO_SUSPEND Automatic (device idle) runtime suspend was
435 * initiated by the subsystem.
436 *
437 * AUTO_RESUME Automatic (device needed) runtime resume was
438 * requested by a driver.
439 */
440
441 #define PM_EVENT_INVALID (-1)
442 #define PM_EVENT_ON 0x0000
443 #define PM_EVENT_FREEZE 0x0001
444 #define PM_EVENT_SUSPEND 0x0002
445 #define PM_EVENT_HIBERNATE 0x0004
446 #define PM_EVENT_QUIESCE 0x0008
447 #define PM_EVENT_RESUME 0x0010
448 #define PM_EVENT_THAW 0x0020
449 #define PM_EVENT_RESTORE 0x0040
450 #define PM_EVENT_RECOVER 0x0080
451 #define PM_EVENT_USER 0x0100
452 #define PM_EVENT_REMOTE 0x0200
453 #define PM_EVENT_AUTO 0x0400
454
455 #define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
456 #define PM_EVENT_USER_SUSPEND (PM_EVENT_USER | PM_EVENT_SUSPEND)
457 #define PM_EVENT_USER_RESUME (PM_EVENT_USER | PM_EVENT_RESUME)
458 #define PM_EVENT_REMOTE_RESUME (PM_EVENT_REMOTE | PM_EVENT_RESUME)
459 #define PM_EVENT_AUTO_SUSPEND (PM_EVENT_AUTO | PM_EVENT_SUSPEND)
460 #define PM_EVENT_AUTO_RESUME (PM_EVENT_AUTO | PM_EVENT_RESUME)
461
462 #define PMSG_INVALID ((struct pm_message){ .event = PM_EVENT_INVALID, })
463 #define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, })
464 #define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, })
465 #define PMSG_QUIESCE ((struct pm_message){ .event = PM_EVENT_QUIESCE, })
466 #define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
467 #define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
468 #define PMSG_RESUME ((struct pm_message){ .event = PM_EVENT_RESUME, })
469 #define PMSG_THAW ((struct pm_message){ .event = PM_EVENT_THAW, })
470 #define PMSG_RESTORE ((struct pm_message){ .event = PM_EVENT_RESTORE, })
471 #define PMSG_RECOVER ((struct pm_message){ .event = PM_EVENT_RECOVER, })
472 #define PMSG_USER_SUSPEND ((struct pm_message) \
473 { .event = PM_EVENT_USER_SUSPEND, })
474 #define PMSG_USER_RESUME ((struct pm_message) \
475 { .event = PM_EVENT_USER_RESUME, })
476 #define PMSG_REMOTE_RESUME ((struct pm_message) \
477 { .event = PM_EVENT_REMOTE_RESUME, })
478 #define PMSG_AUTO_SUSPEND ((struct pm_message) \
479 { .event = PM_EVENT_AUTO_SUSPEND, })
480 #define PMSG_AUTO_RESUME ((struct pm_message) \
481 { .event = PM_EVENT_AUTO_RESUME, })
482
483 #define PMSG_IS_AUTO(msg) (((msg).event & PM_EVENT_AUTO) != 0)
484
485 /*
486 * Device run-time power management status.
487 *
488 * These status labels are used internally by the PM core to indicate the
489 * current status of a device with respect to the PM core operations. They do
490 * not reflect the actual power state of the device or its status as seen by the
491 * driver.
492 *
493 * RPM_ACTIVE Device is fully operational. Indicates that the device
494 * bus type's ->runtime_resume() callback has completed
495 * successfully.
496 *
497 * RPM_SUSPENDED Device bus type's ->runtime_suspend() callback has
498 * completed successfully. The device is regarded as
499 * suspended.
500 *
501 * RPM_RESUMING Device bus type's ->runtime_resume() callback is being
502 * executed.
503 *
504 * RPM_SUSPENDING Device bus type's ->runtime_suspend() callback is being
505 * executed.
506 */
507
508 enum rpm_status {
509 RPM_ACTIVE = 0,
510 RPM_RESUMING,
511 RPM_SUSPENDED,
512 RPM_SUSPENDING,
513 };
514
515 /*
516 * Device run-time power management request types.
517 *
518 * RPM_REQ_NONE Do nothing.
519 *
520 * RPM_REQ_IDLE Run the device bus type's ->runtime_idle() callback
521 *
522 * RPM_REQ_SUSPEND Run the device bus type's ->runtime_suspend() callback
523 *
524 * RPM_REQ_AUTOSUSPEND Same as RPM_REQ_SUSPEND, but not until the device has
525 * been inactive for as long as power.autosuspend_delay
526 *
527 * RPM_REQ_RESUME Run the device bus type's ->runtime_resume() callback
528 */
529
530 enum rpm_request {
531 RPM_REQ_NONE = 0,
532 RPM_REQ_IDLE,
533 RPM_REQ_SUSPEND,
534 RPM_REQ_AUTOSUSPEND,
535 RPM_REQ_RESUME,
536 };
537
538 struct wakeup_source;
539 struct wake_irq;
540 struct pm_domain_data;
541
542 struct pm_subsys_data {
543 spinlock_t lock;
544 unsigned int refcount;
545 #ifdef CONFIG_PM_CLK
546 struct list_head clock_list;
547 #endif
548 #ifdef CONFIG_PM_GENERIC_DOMAINS
549 struct pm_domain_data *domain_data;
550 #endif
551 };
552
553 /*
554 * Driver flags to control system suspend/resume behavior.
555 *
556 * These flags can be set by device drivers at the probe time. They need not be
557 * cleared by the drivers as the driver core will take care of that.
558 *
559 * NEVER_SKIP: Do not skip all system suspend/resume callbacks for the device.
560 * SMART_PREPARE: Check the return value of the driver's ->prepare callback.
561 * SMART_SUSPEND: No need to resume the device from runtime suspend.
562 * LEAVE_SUSPENDED: Avoid resuming the device during system resume if possible.
563 *
564 * Setting SMART_PREPARE instructs bus types and PM domains which may want
565 * system suspend/resume callbacks to be skipped for the device to return 0 from
566 * their ->prepare callbacks if the driver's ->prepare callback returns 0 (in
567 * other words, the system suspend/resume callbacks can only be skipped for the
568 * device if its driver doesn't object against that). This flag has no effect
569 * if NEVER_SKIP is set.
570 *
571 * Setting SMART_SUSPEND instructs bus types and PM domains which may want to
572 * runtime resume the device upfront during system suspend that doing so is not
573 * necessary from the driver's perspective. It also may cause them to skip
574 * invocations of the ->suspend_late and ->suspend_noirq callbacks provided by
575 * the driver if they decide to leave the device in runtime suspend.
576 *
577 * Setting LEAVE_SUSPENDED informs the PM core and middle-layer code that the
578 * driver prefers the device to be left in suspend after system resume.
579 */
580 #define DPM_FLAG_NEVER_SKIP BIT(0)
581 #define DPM_FLAG_SMART_PREPARE BIT(1)
582 #define DPM_FLAG_SMART_SUSPEND BIT(2)
583 #define DPM_FLAG_LEAVE_SUSPENDED BIT(3)
584
585 struct dev_pm_info {
586 pm_message_t power_state;
587 unsigned int can_wakeup:1;
588 unsigned int async_suspend:1;
589 bool in_dpm_list:1; /* Owned by the PM core */
590 bool is_prepared:1; /* Owned by the PM core */
591 bool is_suspended:1; /* Ditto */
592 bool is_noirq_suspended:1;
593 bool is_late_suspended:1;
594 bool early_init:1; /* Owned by the PM core */
595 bool direct_complete:1; /* Owned by the PM core */
596 u32 driver_flags;
597 spinlock_t lock;
598 #ifdef CONFIG_PM_SLEEP
599 struct list_head entry;
600 struct completion completion;
601 struct wakeup_source *wakeup;
602 bool wakeup_path:1;
603 bool syscore:1;
604 bool no_pm_callbacks:1; /* Owned by the PM core */
605 unsigned int must_resume:1; /* Owned by the PM core */
606 unsigned int may_skip_resume:1; /* Set by subsystems */
607 #else
608 unsigned int should_wakeup:1;
609 #endif
610 #ifdef CONFIG_PM
611 struct timer_list suspend_timer;
612 unsigned long timer_expires;
613 struct work_struct work;
614 wait_queue_head_t wait_queue;
615 struct wake_irq *wakeirq;
616 atomic_t usage_count;
617 atomic_t child_count;
618 unsigned int disable_depth:3;
619 unsigned int idle_notification:1;
620 unsigned int request_pending:1;
621 unsigned int deferred_resume:1;
622 unsigned int runtime_auto:1;
623 bool ignore_children:1;
624 unsigned int no_callbacks:1;
625 unsigned int irq_safe:1;
626 unsigned int use_autosuspend:1;
627 unsigned int timer_autosuspends:1;
628 unsigned int memalloc_noio:1;
629 unsigned int links_count;
630 enum rpm_request request;
631 enum rpm_status runtime_status;
632 int runtime_error;
633 int autosuspend_delay;
634 unsigned long last_busy;
635 unsigned long active_jiffies;
636 unsigned long suspended_jiffies;
637 unsigned long accounting_timestamp;
638 #endif
639 struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */
640 void (*set_latency_tolerance)(struct device *, s32);
641 struct dev_pm_qos *qos;
642 };
643
644 extern void update_pm_runtime_accounting(struct device *dev);
645 extern int dev_pm_get_subsys_data(struct device *dev);
646 extern void dev_pm_put_subsys_data(struct device *dev);
647
648 /**
649 * struct dev_pm_domain - power management domain representation.
650 *
651 * @ops: Power management operations associated with this domain.
652 * @detach: Called when removing a device from the domain.
653 * @activate: Called before executing probe routines for bus types and drivers.
654 * @sync: Called after successful driver probe.
655 * @dismiss: Called after unsuccessful driver probe and after driver removal.
656 *
657 * Power domains provide callbacks that are executed during system suspend,
658 * hibernation, system resume and during runtime PM transitions instead of
659 * subsystem-level and driver-level callbacks.
660 */
661 struct dev_pm_domain {
662 struct dev_pm_ops ops;
663 void (*detach)(struct device *dev, bool power_off);
664 int (*activate)(struct device *dev);
665 void (*sync)(struct device *dev);
666 void (*dismiss)(struct device *dev);
667 };
668
669 /*
670 * The PM_EVENT_ messages are also used by drivers implementing the legacy
671 * suspend framework, based on the ->suspend() and ->resume() callbacks common
672 * for suspend and hibernation transitions, according to the rules below.
673 */
674
675 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
676 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
677
678 /*
679 * One transition is triggered by resume(), after a suspend() call; the
680 * message is implicit:
681 *
682 * ON Driver starts working again, responding to hardware events
683 * and software requests. The hardware may have gone through
684 * a power-off reset, or it may have maintained state from the
685 * previous suspend() which the driver will rely on while
686 * resuming. On most platforms, there are no restrictions on
687 * availability of resources like clocks during resume().
688 *
689 * Other transitions are triggered by messages sent using suspend(). All
690 * these transitions quiesce the driver, so that I/O queues are inactive.
691 * That commonly entails turning off IRQs and DMA; there may be rules
692 * about how to quiesce that are specific to the bus or the device's type.
693 * (For example, network drivers mark the link state.) Other details may
694 * differ according to the message:
695 *
696 * SUSPEND Quiesce, enter a low power device state appropriate for
697 * the upcoming system state (such as PCI_D3hot), and enable
698 * wakeup events as appropriate.
699 *
700 * HIBERNATE Enter a low power device state appropriate for the hibernation
701 * state (eg. ACPI S4) and enable wakeup events as appropriate.
702 *
703 * FREEZE Quiesce operations so that a consistent image can be saved;
704 * but do NOT otherwise enter a low power device state, and do
705 * NOT emit system wakeup events.
706 *
707 * PRETHAW Quiesce as if for FREEZE; additionally, prepare for restoring
708 * the system from a snapshot taken after an earlier FREEZE.
709 * Some drivers will need to reset their hardware state instead
710 * of preserving it, to ensure that it's never mistaken for the
711 * state which that earlier snapshot had set up.
712 *
713 * A minimally power-aware driver treats all messages as SUSPEND, fully
714 * reinitializes its device during resume() -- whether or not it was reset
715 * during the suspend/resume cycle -- and can't issue wakeup events.
716 *
717 * More power-aware drivers may also use low power states at runtime as
718 * well as during system sleep states like PM_SUSPEND_STANDBY. They may
719 * be able to use wakeup events to exit from runtime low-power states,
720 * or from system low-power states such as standby or suspend-to-RAM.
721 */
722
723 #ifdef CONFIG_PM_SLEEP
724 extern void device_pm_lock(void);
725 extern void dpm_resume_start(pm_message_t state);
726 extern void dpm_resume_end(pm_message_t state);
727 extern void dpm_noirq_resume_devices(pm_message_t state);
728 extern void dpm_noirq_end(void);
729 extern void dpm_resume_noirq(pm_message_t state);
730 extern void dpm_resume_early(pm_message_t state);
731 extern void dpm_resume(pm_message_t state);
732 extern void dpm_complete(pm_message_t state);
733
734 extern void device_pm_unlock(void);
735 extern int dpm_suspend_end(pm_message_t state);
736 extern int dpm_suspend_start(pm_message_t state);
737 extern void dpm_noirq_begin(void);
738 extern int dpm_noirq_suspend_devices(pm_message_t state);
739 extern int dpm_suspend_noirq(pm_message_t state);
740 extern int dpm_suspend_late(pm_message_t state);
741 extern int dpm_suspend(pm_message_t state);
742 extern int dpm_prepare(pm_message_t state);
743
744 extern void __suspend_report_result(const char *function, void *fn, int ret);
745
746 #define suspend_report_result(fn, ret) \
747 do { \
748 __suspend_report_result(__func__, fn, ret); \
749 } while (0)
750
751 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
752 extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
753
754 extern int pm_generic_prepare(struct device *dev);
755 extern int pm_generic_suspend_late(struct device *dev);
756 extern int pm_generic_suspend_noirq(struct device *dev);
757 extern int pm_generic_suspend(struct device *dev);
758 extern int pm_generic_resume_early(struct device *dev);
759 extern int pm_generic_resume_noirq(struct device *dev);
760 extern int pm_generic_resume(struct device *dev);
761 extern int pm_generic_freeze_noirq(struct device *dev);
762 extern int pm_generic_freeze_late(struct device *dev);
763 extern int pm_generic_freeze(struct device *dev);
764 extern int pm_generic_thaw_noirq(struct device *dev);
765 extern int pm_generic_thaw_early(struct device *dev);
766 extern int pm_generic_thaw(struct device *dev);
767 extern int pm_generic_restore_noirq(struct device *dev);
768 extern int pm_generic_restore_early(struct device *dev);
769 extern int pm_generic_restore(struct device *dev);
770 extern int pm_generic_poweroff_noirq(struct device *dev);
771 extern int pm_generic_poweroff_late(struct device *dev);
772 extern int pm_generic_poweroff(struct device *dev);
773 extern void pm_generic_complete(struct device *dev);
774
775 extern void dev_pm_skip_next_resume_phases(struct device *dev);
776 extern bool dev_pm_may_skip_resume(struct device *dev);
777 extern bool dev_pm_smart_suspend_and_suspended(struct device *dev);
778
779 #else /* !CONFIG_PM_SLEEP */
780
781 #define device_pm_lock() do {} while (0)
782 #define device_pm_unlock() do {} while (0)
783
dpm_suspend_start(pm_message_t state)784 static inline int dpm_suspend_start(pm_message_t state)
785 {
786 return 0;
787 }
788
789 #define suspend_report_result(fn, ret) do {} while (0)
790
device_pm_wait_for_dev(struct device * a,struct device * b)791 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
792 {
793 return 0;
794 }
795
dpm_for_each_dev(void * data,void (* fn)(struct device *,void *))796 static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
797 {
798 }
799
800 #define pm_generic_prepare NULL
801 #define pm_generic_suspend_late NULL
802 #define pm_generic_suspend_noirq NULL
803 #define pm_generic_suspend NULL
804 #define pm_generic_resume_early NULL
805 #define pm_generic_resume_noirq NULL
806 #define pm_generic_resume NULL
807 #define pm_generic_freeze_noirq NULL
808 #define pm_generic_freeze_late NULL
809 #define pm_generic_freeze NULL
810 #define pm_generic_thaw_noirq NULL
811 #define pm_generic_thaw_early NULL
812 #define pm_generic_thaw NULL
813 #define pm_generic_restore_noirq NULL
814 #define pm_generic_restore_early NULL
815 #define pm_generic_restore NULL
816 #define pm_generic_poweroff_noirq NULL
817 #define pm_generic_poweroff_late NULL
818 #define pm_generic_poweroff NULL
819 #define pm_generic_complete NULL
820 #endif /* !CONFIG_PM_SLEEP */
821
822 /* How to reorder dpm_list after device_move() */
823 enum dpm_order {
824 DPM_ORDER_NONE,
825 DPM_ORDER_DEV_AFTER_PARENT,
826 DPM_ORDER_PARENT_BEFORE_DEV,
827 DPM_ORDER_DEV_LAST,
828 };
829
830 #endif /* _LINUX_PM_H */
831