1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * pm.h - Power management interface
4 *
5 * Copyright (C) 2000 Andrew Henroid
6 */
7
8 #ifndef _LINUX_PM_H
9 #define _LINUX_PM_H
10
11 #include <linux/list.h>
12 #include <linux/workqueue.h>
13 #include <linux/spinlock.h>
14 #include <linux/wait.h>
15 #include <linux/timer.h>
16 #include <linux/hrtimer.h>
17 #include <linux/completion.h>
18
19 /*
20 * Callbacks for platform drivers to implement.
21 */
22 extern void (*pm_power_off)(void);
23 extern void (*pm_power_off_prepare)(void);
24
25 struct device; /* we have a circular dep with device.h */
26 #ifdef CONFIG_VT_CONSOLE_SLEEP
27 extern void pm_vt_switch_required(struct device *dev, bool required);
28 extern void pm_vt_switch_unregister(struct device *dev);
29 #else
pm_vt_switch_required(struct device * dev,bool required)30 static inline void pm_vt_switch_required(struct device *dev, bool required)
31 {
32 }
pm_vt_switch_unregister(struct device * dev)33 static inline void pm_vt_switch_unregister(struct device *dev)
34 {
35 }
36 #endif /* CONFIG_VT_CONSOLE_SLEEP */
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 * @prepare: The principal role of this callback is to prevent new children of
58 * the device from being registered after it has returned (the driver's
59 * subsystem and generally the rest of the kernel is supposed to prevent
60 * new calls to the probe method from being made too once @prepare() has
61 * succeeded). If @prepare() detects a situation it cannot handle (e.g.
62 * registration of a child already in progress), it may return -EAGAIN, so
63 * that the PM core can execute it once again (e.g. after a new child has
64 * been registered) to recover from the race condition.
65 * This method is executed for all kinds of suspend transitions and is
66 * followed by one of the suspend callbacks: @suspend(), @freeze(), or
67 * @poweroff(). If the transition is a suspend to memory or standby (that
68 * is, not related to hibernation), the return value of @prepare() may be
69 * used to indicate to the PM core to leave the device in runtime suspend
70 * if applicable. Namely, if @prepare() returns a positive number, the PM
71 * core will understand that as a declaration that the device appears to be
72 * runtime-suspended and it may be left in that state during the entire
73 * transition and during the subsequent resume if all of its descendants
74 * are left in runtime suspend too. If that happens, @complete() will be
75 * executed directly after @prepare() and it must ensure the proper
76 * functioning of the device after the system resume.
77 * The PM core executes subsystem-level @prepare() for all devices before
78 * starting to invoke suspend callbacks for any of them, so generally
79 * devices may be assumed to be functional or to respond to runtime resume
80 * requests while @prepare() is being executed. However, device drivers
81 * may NOT assume anything about the availability of user space at that
82 * time and it is NOT valid to request firmware from within @prepare()
83 * (it's too late to do that). It also is NOT valid to allocate
84 * substantial amounts of memory from @prepare() in the GFP_KERNEL mode.
85 * [To work around these limitations, drivers may register suspend and
86 * hibernation notifiers to be executed before the freezing of tasks.]
87 *
88 * @complete: Undo the changes made by @prepare(). This method is executed for
89 * all kinds of resume transitions, following one of the resume callbacks:
90 * @resume(), @thaw(), @restore(). Also called if the state transition
91 * fails before the driver's suspend callback: @suspend(), @freeze() or
92 * @poweroff(), can be executed (e.g. if the suspend callback fails for one
93 * of the other devices that the PM core has unsuccessfully attempted to
94 * suspend earlier).
95 * The PM core executes subsystem-level @complete() after it has executed
96 * the appropriate resume callbacks for all devices. If the corresponding
97 * @prepare() at the beginning of the suspend transition returned a
98 * positive number and the device was left in runtime suspend (without
99 * executing any suspend and resume callbacks for it), @complete() will be
100 * the only callback executed for the device during resume. In that case,
101 * @complete() must be prepared to do whatever is necessary to ensure the
102 * proper functioning of the device after the system resume. To this end,
103 * @complete() can check the power.direct_complete flag of the device to
104 * learn whether (unset) or not (set) the previous suspend and resume
105 * callbacks have been executed for it.
106 *
107 * @suspend: Executed before putting the system into a sleep state in which the
108 * contents of main memory are preserved. The exact action to perform
109 * depends on the device's subsystem (PM domain, device type, class or bus
110 * type), but generally the device must be quiescent after subsystem-level
111 * @suspend() has returned, so that it doesn't do any I/O or DMA.
112 * Subsystem-level @suspend() is executed for all devices after invoking
113 * subsystem-level @prepare() for all of them.
114 *
115 * @suspend_late: Continue operations started by @suspend(). For a number of
116 * devices @suspend_late() may point to the same callback routine as the
117 * runtime suspend callback.
118 *
119 * @resume: Executed after waking the system up from a sleep state in which the
120 * contents of main memory were preserved. The exact action to perform
121 * depends on the device's subsystem, but generally the driver is expected
122 * to start working again, responding to hardware events and software
123 * requests (the device itself may be left in a low-power state, waiting
124 * for a runtime resume to occur). The state of the device at the time its
125 * driver's @resume() callback is run depends on the platform and subsystem
126 * the device belongs to. On most platforms, there are no restrictions on
127 * availability of resources like clocks during @resume().
128 * Subsystem-level @resume() is executed for all devices after invoking
129 * subsystem-level @resume_noirq() for all of them.
130 *
131 * @resume_early: Prepare to execute @resume(). For a number of devices
132 * @resume_early() may point to the same callback routine as the runtime
133 * resume callback.
134 *
135 * @freeze: Hibernation-specific, executed before creating a hibernation image.
136 * Analogous to @suspend(), but it should not enable the device to signal
137 * wakeup events or change its power state. The majority of subsystems
138 * (with the notable exception of the PCI bus type) expect the driver-level
139 * @freeze() to save the device settings in memory to be used by @restore()
140 * during the subsequent resume from hibernation.
141 * Subsystem-level @freeze() is executed for all devices after invoking
142 * subsystem-level @prepare() for all of them.
143 *
144 * @freeze_late: Continue operations started by @freeze(). Analogous to
145 * @suspend_late(), but it should not enable the device to signal wakeup
146 * events or change its power state.
147 *
148 * @thaw: Hibernation-specific, executed after creating a hibernation image OR
149 * if the creation of an image has failed. Also executed after a failing
150 * attempt to restore the contents of main memory from such an image.
151 * Undo the changes made by the preceding @freeze(), so the device can be
152 * operated in the same way as immediately before the call to @freeze().
153 * Subsystem-level @thaw() is executed for all devices after invoking
154 * subsystem-level @thaw_noirq() for all of them. It also may be executed
155 * directly after @freeze() in case of a transition error.
156 *
157 * @thaw_early: Prepare to execute @thaw(). Undo the changes made by the
158 * preceding @freeze_late().
159 *
160 * @poweroff: Hibernation-specific, executed after saving a hibernation image.
161 * Analogous to @suspend(), but it need not save the device's settings in
162 * memory.
163 * Subsystem-level @poweroff() is executed for all devices after invoking
164 * subsystem-level @prepare() for all of them.
165 *
166 * @poweroff_late: Continue operations started by @poweroff(). Analogous to
167 * @suspend_late(), but it need not save the device's settings in memory.
168 *
169 * @restore: Hibernation-specific, executed after restoring the contents of main
170 * memory from a hibernation image, analogous to @resume().
171 *
172 * @restore_early: Prepare to execute @restore(), analogous to @resume_early().
173 *
174 * @suspend_noirq: Complete the actions started by @suspend(). Carry out any
175 * additional operations required for suspending the device that might be
176 * racing with its driver's interrupt handler, which is guaranteed not to
177 * run while @suspend_noirq() is being executed.
178 * It generally is expected that the device will be in a low-power state
179 * (appropriate for the target system sleep state) after subsystem-level
180 * @suspend_noirq() has returned successfully. If the device can generate
181 * system wakeup signals and is enabled to wake up the system, it should be
182 * configured to do so at that time. However, depending on the platform
183 * and device's subsystem, @suspend() or @suspend_late() may be allowed to
184 * put the device into the low-power state and configure it to generate
185 * wakeup signals, in which case it generally is not necessary to define
186 * @suspend_noirq().
187 *
188 * @resume_noirq: Prepare for the execution of @resume() by carrying out any
189 * operations required for resuming the device that might be racing with
190 * its driver's interrupt handler, which is guaranteed not to run while
191 * @resume_noirq() is being executed.
192 *
193 * @freeze_noirq: Complete the actions started by @freeze(). Carry out any
194 * additional operations required for freezing the device that might be
195 * racing with its driver's interrupt handler, which is guaranteed not to
196 * run while @freeze_noirq() is being executed.
197 * The power state of the device should not be changed by either @freeze(),
198 * or @freeze_late(), or @freeze_noirq() and it should not be configured to
199 * signal system wakeup by any of these callbacks.
200 *
201 * @thaw_noirq: Prepare for the execution of @thaw() by carrying out any
202 * operations required for thawing the device that might be racing with its
203 * driver's interrupt handler, which is guaranteed not to run while
204 * @thaw_noirq() is being executed.
205 *
206 * @poweroff_noirq: Complete the actions started by @poweroff(). Analogous to
207 * @suspend_noirq(), but it need not save the device's settings in memory.
208 *
209 * @restore_noirq: Prepare for the execution of @restore() by carrying out any
210 * operations required for thawing the device that might be racing with its
211 * driver's interrupt handler, which is guaranteed not to run while
212 * @restore_noirq() is being executed. Analogous to @resume_noirq().
213 *
214 * @runtime_suspend: Prepare the device for a condition in which it won't be
215 * able to communicate with the CPU(s) and RAM due to power management.
216 * This need not mean that the device should be put into a low-power state.
217 * For example, if the device is behind a link which is about to be turned
218 * off, the device may remain at full power. If the device does go to low
219 * power and is capable of generating runtime wakeup events, remote wakeup
220 * (i.e., a hardware mechanism allowing the device to request a change of
221 * its power state via an interrupt) should be enabled for it.
222 *
223 * @runtime_resume: Put the device into the fully active state in response to a
224 * wakeup event generated by hardware or at the request of software. If
225 * necessary, put the device into the full-power state and restore its
226 * registers, so that it is fully operational.
227 *
228 * @runtime_idle: Device appears to be inactive and it might be put into a
229 * low-power state if all of the necessary conditions are satisfied.
230 * Check these conditions, and return 0 if it's appropriate to let the PM
231 * core queue a suspend request for the device.
232 *
233 * Several device power state transitions are externally visible, affecting
234 * the state of pending I/O queues and (for drivers that touch hardware)
235 * interrupts, wakeups, DMA, and other hardware state. There may also be
236 * internal transitions to various low-power modes which are transparent
237 * to the rest of the driver stack (such as a driver that's ON gating off
238 * clocks which are not in active use).
239 *
240 * The externally visible transitions are handled with the help of callbacks
241 * included in this structure in such a way that, typically, two levels of
242 * callbacks are involved. First, the PM core executes callbacks provided by PM
243 * domains, device types, classes and bus types. They are the subsystem-level
244 * callbacks expected to execute callbacks provided by device drivers, although
245 * they may choose not to do that. If the driver callbacks are executed, they
246 * have to collaborate with the subsystem-level callbacks to achieve the goals
247 * appropriate for the given system transition, given transition phase and the
248 * subsystem the device belongs to.
249 *
250 * All of the above callbacks, except for @complete(), return error codes.
251 * However, the error codes returned by @resume(), @thaw(), @restore(),
252 * @resume_noirq(), @thaw_noirq(), and @restore_noirq(), do not cause the PM
253 * core to abort the resume transition during which they are returned. The
254 * error codes returned in those cases are only printed to the system logs for
255 * debugging purposes. Still, it is recommended that drivers only return error
256 * codes from their resume methods in case of an unrecoverable failure (i.e.
257 * when the device being handled refuses to resume and becomes unusable) to
258 * allow the PM core to be modified in the future, so that it can avoid
259 * attempting to handle devices that failed to resume and their children.
260 *
261 * It is allowed to unregister devices while the above callbacks are being
262 * executed. However, a callback routine MUST NOT try to unregister the device
263 * it was called for, although it may unregister children of that device (for
264 * example, if it detects that a child was unplugged while the system was
265 * asleep).
266 *
267 * There also are callbacks related to runtime power management of devices.
268 * Again, as a rule these callbacks are executed by the PM core for subsystems
269 * (PM domains, device types, classes and bus types) and the subsystem-level
270 * callbacks are expected to invoke the driver callbacks. Moreover, the exact
271 * actions to be performed by a device driver's callbacks generally depend on
272 * the platform and subsystem the device belongs to.
273 *
274 * Refer to Documentation/power/runtime_pm.rst for more information about the
275 * role of the @runtime_suspend(), @runtime_resume() and @runtime_idle()
276 * callbacks in device runtime power management.
277 */
278 struct dev_pm_ops {
279 int (*prepare)(struct device *dev);
280 void (*complete)(struct device *dev);
281 int (*suspend)(struct device *dev);
282 int (*resume)(struct device *dev);
283 int (*freeze)(struct device *dev);
284 int (*thaw)(struct device *dev);
285 int (*poweroff)(struct device *dev);
286 int (*restore)(struct device *dev);
287 int (*suspend_late)(struct device *dev);
288 int (*resume_early)(struct device *dev);
289 int (*freeze_late)(struct device *dev);
290 int (*thaw_early)(struct device *dev);
291 int (*poweroff_late)(struct device *dev);
292 int (*restore_early)(struct device *dev);
293 int (*suspend_noirq)(struct device *dev);
294 int (*resume_noirq)(struct device *dev);
295 int (*freeze_noirq)(struct device *dev);
296 int (*thaw_noirq)(struct device *dev);
297 int (*poweroff_noirq)(struct device *dev);
298 int (*restore_noirq)(struct device *dev);
299 int (*runtime_suspend)(struct device *dev);
300 int (*runtime_resume)(struct device *dev);
301 int (*runtime_idle)(struct device *dev);
302 };
303
304 #ifdef CONFIG_PM_SLEEP
305 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
306 .suspend = suspend_fn, \
307 .resume = resume_fn, \
308 .freeze = suspend_fn, \
309 .thaw = resume_fn, \
310 .poweroff = suspend_fn, \
311 .restore = resume_fn,
312 #else
313 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
314 #endif
315
316 #ifdef CONFIG_PM_SLEEP
317 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
318 .suspend_late = suspend_fn, \
319 .resume_early = resume_fn, \
320 .freeze_late = suspend_fn, \
321 .thaw_early = resume_fn, \
322 .poweroff_late = suspend_fn, \
323 .restore_early = resume_fn,
324 #else
325 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
326 #endif
327
328 #ifdef CONFIG_PM_SLEEP
329 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
330 .suspend_noirq = suspend_fn, \
331 .resume_noirq = resume_fn, \
332 .freeze_noirq = suspend_fn, \
333 .thaw_noirq = resume_fn, \
334 .poweroff_noirq = suspend_fn, \
335 .restore_noirq = resume_fn,
336 #else
337 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
338 #endif
339
340 #ifdef CONFIG_PM
341 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
342 .runtime_suspend = suspend_fn, \
343 .runtime_resume = resume_fn, \
344 .runtime_idle = idle_fn,
345 #else
346 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
347 #endif
348
349 /*
350 * Use this if you want to use the same suspend and resume callbacks for suspend
351 * to RAM and hibernation.
352 */
353 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
354 const struct dev_pm_ops __maybe_unused name = { \
355 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
356 }
357
358 /*
359 * Use this for defining a set of PM operations to be used in all situations
360 * (system suspend, hibernation or runtime PM).
361 * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
362 * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
363 * and .runtime_resume(), because .runtime_suspend() always works on an already
364 * quiescent device, while .suspend() should assume that the device may be doing
365 * something when it is called (it should ensure that the device will be
366 * quiescent after it has returned). Therefore it's better to point the "late"
367 * suspend and "early" resume callback pointers, .suspend_late() and
368 * .resume_early(), to the same routines as .runtime_suspend() and
369 * .runtime_resume(), respectively (and analogously for hibernation).
370 */
371 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
372 const struct dev_pm_ops __maybe_unused name = { \
373 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
374 SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
375 }
376
377 #ifdef CONFIG_PM
378 #define pm_ptr(_ptr) (_ptr)
379 #else
380 #define pm_ptr(_ptr) NULL
381 #endif
382
383 /*
384 * PM_EVENT_ messages
385 *
386 * The following PM_EVENT_ messages are defined for the internal use of the PM
387 * core, in order to provide a mechanism allowing the high level suspend and
388 * hibernation code to convey the necessary information to the device PM core
389 * code:
390 *
391 * ON No transition.
392 *
393 * FREEZE System is going to hibernate, call ->prepare() and ->freeze()
394 * for all devices.
395 *
396 * SUSPEND System is going to suspend, call ->prepare() and ->suspend()
397 * for all devices.
398 *
399 * HIBERNATE Hibernation image has been saved, call ->prepare() and
400 * ->poweroff() for all devices.
401 *
402 * QUIESCE Contents of main memory are going to be restored from a (loaded)
403 * hibernation image, call ->prepare() and ->freeze() for all
404 * devices.
405 *
406 * RESUME System is resuming, call ->resume() and ->complete() for all
407 * devices.
408 *
409 * THAW Hibernation image has been created, call ->thaw() and
410 * ->complete() for all devices.
411 *
412 * RESTORE Contents of main memory have been restored from a hibernation
413 * image, call ->restore() and ->complete() for all devices.
414 *
415 * RECOVER Creation of a hibernation image or restoration of the main
416 * memory contents from a hibernation image has failed, call
417 * ->thaw() and ->complete() for all devices.
418 *
419 * The following PM_EVENT_ messages are defined for internal use by
420 * kernel subsystems. They are never issued by the PM core.
421 *
422 * USER_SUSPEND Manual selective suspend was issued by userspace.
423 *
424 * USER_RESUME Manual selective resume was issued by userspace.
425 *
426 * REMOTE_WAKEUP Remote-wakeup request was received from the device.
427 *
428 * AUTO_SUSPEND Automatic (device idle) runtime suspend was
429 * initiated by the subsystem.
430 *
431 * AUTO_RESUME Automatic (device needed) runtime resume was
432 * requested by a driver.
433 */
434
435 #define PM_EVENT_INVALID (-1)
436 #define PM_EVENT_ON 0x0000
437 #define PM_EVENT_FREEZE 0x0001
438 #define PM_EVENT_SUSPEND 0x0002
439 #define PM_EVENT_HIBERNATE 0x0004
440 #define PM_EVENT_QUIESCE 0x0008
441 #define PM_EVENT_RESUME 0x0010
442 #define PM_EVENT_THAW 0x0020
443 #define PM_EVENT_RESTORE 0x0040
444 #define PM_EVENT_RECOVER 0x0080
445 #define PM_EVENT_USER 0x0100
446 #define PM_EVENT_REMOTE 0x0200
447 #define PM_EVENT_AUTO 0x0400
448
449 #define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
450 #define PM_EVENT_USER_SUSPEND (PM_EVENT_USER | PM_EVENT_SUSPEND)
451 #define PM_EVENT_USER_RESUME (PM_EVENT_USER | PM_EVENT_RESUME)
452 #define PM_EVENT_REMOTE_RESUME (PM_EVENT_REMOTE | PM_EVENT_RESUME)
453 #define PM_EVENT_AUTO_SUSPEND (PM_EVENT_AUTO | PM_EVENT_SUSPEND)
454 #define PM_EVENT_AUTO_RESUME (PM_EVENT_AUTO | PM_EVENT_RESUME)
455
456 #define PMSG_INVALID ((struct pm_message){ .event = PM_EVENT_INVALID, })
457 #define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, })
458 #define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, })
459 #define PMSG_QUIESCE ((struct pm_message){ .event = PM_EVENT_QUIESCE, })
460 #define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
461 #define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
462 #define PMSG_RESUME ((struct pm_message){ .event = PM_EVENT_RESUME, })
463 #define PMSG_THAW ((struct pm_message){ .event = PM_EVENT_THAW, })
464 #define PMSG_RESTORE ((struct pm_message){ .event = PM_EVENT_RESTORE, })
465 #define PMSG_RECOVER ((struct pm_message){ .event = PM_EVENT_RECOVER, })
466 #define PMSG_USER_SUSPEND ((struct pm_message) \
467 { .event = PM_EVENT_USER_SUSPEND, })
468 #define PMSG_USER_RESUME ((struct pm_message) \
469 { .event = PM_EVENT_USER_RESUME, })
470 #define PMSG_REMOTE_RESUME ((struct pm_message) \
471 { .event = PM_EVENT_REMOTE_RESUME, })
472 #define PMSG_AUTO_SUSPEND ((struct pm_message) \
473 { .event = PM_EVENT_AUTO_SUSPEND, })
474 #define PMSG_AUTO_RESUME ((struct pm_message) \
475 { .event = PM_EVENT_AUTO_RESUME, })
476
477 #define PMSG_IS_AUTO(msg) (((msg).event & PM_EVENT_AUTO) != 0)
478
479 /*
480 * Device run-time power management status.
481 *
482 * These status labels are used internally by the PM core to indicate the
483 * current status of a device with respect to the PM core operations. They do
484 * not reflect the actual power state of the device or its status as seen by the
485 * driver.
486 *
487 * RPM_ACTIVE Device is fully operational. Indicates that the device
488 * bus type's ->runtime_resume() callback has completed
489 * successfully.
490 *
491 * RPM_SUSPENDED Device bus type's ->runtime_suspend() callback has
492 * completed successfully. The device is regarded as
493 * suspended.
494 *
495 * RPM_RESUMING Device bus type's ->runtime_resume() callback is being
496 * executed.
497 *
498 * RPM_SUSPENDING Device bus type's ->runtime_suspend() callback is being
499 * executed.
500 */
501
502 enum rpm_status {
503 RPM_ACTIVE = 0,
504 RPM_RESUMING,
505 RPM_SUSPENDED,
506 RPM_SUSPENDING,
507 };
508
509 /*
510 * Device run-time power management request types.
511 *
512 * RPM_REQ_NONE Do nothing.
513 *
514 * RPM_REQ_IDLE Run the device bus type's ->runtime_idle() callback
515 *
516 * RPM_REQ_SUSPEND Run the device bus type's ->runtime_suspend() callback
517 *
518 * RPM_REQ_AUTOSUSPEND Same as RPM_REQ_SUSPEND, but not until the device has
519 * been inactive for as long as power.autosuspend_delay
520 *
521 * RPM_REQ_RESUME Run the device bus type's ->runtime_resume() callback
522 */
523
524 enum rpm_request {
525 RPM_REQ_NONE = 0,
526 RPM_REQ_IDLE,
527 RPM_REQ_SUSPEND,
528 RPM_REQ_AUTOSUSPEND,
529 RPM_REQ_RESUME,
530 };
531
532 struct wakeup_source;
533 struct wake_irq;
534 struct pm_domain_data;
535
536 struct pm_subsys_data {
537 spinlock_t lock;
538 unsigned int refcount;
539 #ifdef CONFIG_PM_CLK
540 struct list_head clock_list;
541 #endif
542 #ifdef CONFIG_PM_GENERIC_DOMAINS
543 struct pm_domain_data *domain_data;
544 #endif
545 };
546
547 /*
548 * Driver flags to control system suspend/resume behavior.
549 *
550 * These flags can be set by device drivers at the probe time. They need not be
551 * cleared by the drivers as the driver core will take care of that.
552 *
553 * NO_DIRECT_COMPLETE: Do not apply direct-complete optimization to the device.
554 * SMART_PREPARE: Take the driver ->prepare callback return value into account.
555 * SMART_SUSPEND: Avoid resuming the device from runtime suspend.
556 * MAY_SKIP_RESUME: Allow driver "noirq" and "early" callbacks to be skipped.
557 *
558 * See Documentation/driver-api/pm/devices.rst for details.
559 */
560 #define DPM_FLAG_NO_DIRECT_COMPLETE BIT(0)
561 #define DPM_FLAG_SMART_PREPARE BIT(1)
562 #define DPM_FLAG_SMART_SUSPEND BIT(2)
563 #define DPM_FLAG_MAY_SKIP_RESUME BIT(3)
564
565 struct dev_pm_info {
566 pm_message_t power_state;
567 unsigned int can_wakeup:1;
568 unsigned int async_suspend:1;
569 bool in_dpm_list:1; /* Owned by the PM core */
570 bool is_prepared:1; /* Owned by the PM core */
571 bool is_suspended:1; /* Ditto */
572 bool is_noirq_suspended:1;
573 bool is_late_suspended:1;
574 bool no_pm:1;
575 bool early_init:1; /* Owned by the PM core */
576 bool direct_complete:1; /* Owned by the PM core */
577 u32 driver_flags;
578 spinlock_t lock;
579 #ifdef CONFIG_PM_SLEEP
580 struct list_head entry;
581 struct completion completion;
582 struct wakeup_source *wakeup;
583 bool wakeup_path:1;
584 bool syscore:1;
585 bool no_pm_callbacks:1; /* Owned by the PM core */
586 unsigned int must_resume:1; /* Owned by the PM core */
587 unsigned int may_skip_resume:1; /* Set by subsystems */
588 #else
589 unsigned int should_wakeup:1;
590 #endif
591 #ifdef CONFIG_PM
592 struct hrtimer suspend_timer;
593 u64 timer_expires;
594 struct work_struct work;
595 wait_queue_head_t wait_queue;
596 struct wake_irq *wakeirq;
597 atomic_t usage_count;
598 atomic_t child_count;
599 unsigned int disable_depth:3;
600 unsigned int idle_notification:1;
601 unsigned int request_pending:1;
602 unsigned int deferred_resume:1;
603 unsigned int runtime_auto:1;
604 bool ignore_children:1;
605 unsigned int no_callbacks:1;
606 unsigned int irq_safe:1;
607 unsigned int use_autosuspend:1;
608 unsigned int timer_autosuspends:1;
609 unsigned int memalloc_noio:1;
610 unsigned int links_count;
611 enum rpm_request request;
612 enum rpm_status runtime_status;
613 int runtime_error;
614 int autosuspend_delay;
615 u64 last_busy;
616 u64 active_time;
617 u64 suspended_time;
618 u64 accounting_timestamp;
619 #endif
620 struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */
621 void (*set_latency_tolerance)(struct device *, s32);
622 struct dev_pm_qos *qos;
623 };
624
625 extern int dev_pm_get_subsys_data(struct device *dev);
626 extern void dev_pm_put_subsys_data(struct device *dev);
627
628 /**
629 * struct dev_pm_domain - power management domain representation.
630 *
631 * @ops: Power management operations associated with this domain.
632 * @start: Called when a user needs to start the device via the domain.
633 * @detach: Called when removing a device from the domain.
634 * @activate: Called before executing probe routines for bus types and drivers.
635 * @sync: Called after successful driver probe.
636 * @dismiss: Called after unsuccessful driver probe and after driver removal.
637 *
638 * Power domains provide callbacks that are executed during system suspend,
639 * hibernation, system resume and during runtime PM transitions instead of
640 * subsystem-level and driver-level callbacks.
641 */
642 struct dev_pm_domain {
643 struct dev_pm_ops ops;
644 int (*start)(struct device *dev);
645 void (*detach)(struct device *dev, bool power_off);
646 int (*activate)(struct device *dev);
647 void (*sync)(struct device *dev);
648 void (*dismiss)(struct device *dev);
649 };
650
651 /*
652 * The PM_EVENT_ messages are also used by drivers implementing the legacy
653 * suspend framework, based on the ->suspend() and ->resume() callbacks common
654 * for suspend and hibernation transitions, according to the rules below.
655 */
656
657 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
658 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
659
660 /*
661 * One transition is triggered by resume(), after a suspend() call; the
662 * message is implicit:
663 *
664 * ON Driver starts working again, responding to hardware events
665 * and software requests. The hardware may have gone through
666 * a power-off reset, or it may have maintained state from the
667 * previous suspend() which the driver will rely on while
668 * resuming. On most platforms, there are no restrictions on
669 * availability of resources like clocks during resume().
670 *
671 * Other transitions are triggered by messages sent using suspend(). All
672 * these transitions quiesce the driver, so that I/O queues are inactive.
673 * That commonly entails turning off IRQs and DMA; there may be rules
674 * about how to quiesce that are specific to the bus or the device's type.
675 * (For example, network drivers mark the link state.) Other details may
676 * differ according to the message:
677 *
678 * SUSPEND Quiesce, enter a low power device state appropriate for
679 * the upcoming system state (such as PCI_D3hot), and enable
680 * wakeup events as appropriate.
681 *
682 * HIBERNATE Enter a low power device state appropriate for the hibernation
683 * state (eg. ACPI S4) and enable wakeup events as appropriate.
684 *
685 * FREEZE Quiesce operations so that a consistent image can be saved;
686 * but do NOT otherwise enter a low power device state, and do
687 * NOT emit system wakeup events.
688 *
689 * PRETHAW Quiesce as if for FREEZE; additionally, prepare for restoring
690 * the system from a snapshot taken after an earlier FREEZE.
691 * Some drivers will need to reset their hardware state instead
692 * of preserving it, to ensure that it's never mistaken for the
693 * state which that earlier snapshot had set up.
694 *
695 * A minimally power-aware driver treats all messages as SUSPEND, fully
696 * reinitializes its device during resume() -- whether or not it was reset
697 * during the suspend/resume cycle -- and can't issue wakeup events.
698 *
699 * More power-aware drivers may also use low power states at runtime as
700 * well as during system sleep states like PM_SUSPEND_STANDBY. They may
701 * be able to use wakeup events to exit from runtime low-power states,
702 * or from system low-power states such as standby or suspend-to-RAM.
703 */
704
705 #ifdef CONFIG_PM_SLEEP
706 extern void device_pm_lock(void);
707 extern void dpm_resume_start(pm_message_t state);
708 extern void dpm_resume_end(pm_message_t state);
709 extern void dpm_resume_noirq(pm_message_t state);
710 extern void dpm_resume_early(pm_message_t state);
711 extern void dpm_resume(pm_message_t state);
712 extern void dpm_complete(pm_message_t state);
713
714 extern void device_pm_unlock(void);
715 extern int dpm_suspend_end(pm_message_t state);
716 extern int dpm_suspend_start(pm_message_t state);
717 extern int dpm_suspend_noirq(pm_message_t state);
718 extern int dpm_suspend_late(pm_message_t state);
719 extern int dpm_suspend(pm_message_t state);
720 extern int dpm_prepare(pm_message_t state);
721
722 extern void __suspend_report_result(const char *function, void *fn, int ret);
723
724 #define suspend_report_result(fn, ret) \
725 do { \
726 __suspend_report_result(__func__, fn, ret); \
727 } while (0)
728
729 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
730 extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
731
732 extern int pm_generic_prepare(struct device *dev);
733 extern int pm_generic_suspend_late(struct device *dev);
734 extern int pm_generic_suspend_noirq(struct device *dev);
735 extern int pm_generic_suspend(struct device *dev);
736 extern int pm_generic_resume_early(struct device *dev);
737 extern int pm_generic_resume_noirq(struct device *dev);
738 extern int pm_generic_resume(struct device *dev);
739 extern int pm_generic_freeze_noirq(struct device *dev);
740 extern int pm_generic_freeze_late(struct device *dev);
741 extern int pm_generic_freeze(struct device *dev);
742 extern int pm_generic_thaw_noirq(struct device *dev);
743 extern int pm_generic_thaw_early(struct device *dev);
744 extern int pm_generic_thaw(struct device *dev);
745 extern int pm_generic_restore_noirq(struct device *dev);
746 extern int pm_generic_restore_early(struct device *dev);
747 extern int pm_generic_restore(struct device *dev);
748 extern int pm_generic_poweroff_noirq(struct device *dev);
749 extern int pm_generic_poweroff_late(struct device *dev);
750 extern int pm_generic_poweroff(struct device *dev);
751 extern void pm_generic_complete(struct device *dev);
752
753 extern bool dev_pm_skip_resume(struct device *dev);
754 extern bool dev_pm_skip_suspend(struct device *dev);
755
756 #else /* !CONFIG_PM_SLEEP */
757
758 #define device_pm_lock() do {} while (0)
759 #define device_pm_unlock() do {} while (0)
760
dpm_suspend_start(pm_message_t state)761 static inline int dpm_suspend_start(pm_message_t state)
762 {
763 return 0;
764 }
765
766 #define suspend_report_result(fn, ret) do {} while (0)
767
device_pm_wait_for_dev(struct device * a,struct device * b)768 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
769 {
770 return 0;
771 }
772
dpm_for_each_dev(void * data,void (* fn)(struct device *,void *))773 static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
774 {
775 }
776
777 #define pm_generic_prepare NULL
778 #define pm_generic_suspend_late NULL
779 #define pm_generic_suspend_noirq NULL
780 #define pm_generic_suspend NULL
781 #define pm_generic_resume_early NULL
782 #define pm_generic_resume_noirq NULL
783 #define pm_generic_resume NULL
784 #define pm_generic_freeze_noirq NULL
785 #define pm_generic_freeze_late NULL
786 #define pm_generic_freeze NULL
787 #define pm_generic_thaw_noirq NULL
788 #define pm_generic_thaw_early NULL
789 #define pm_generic_thaw NULL
790 #define pm_generic_restore_noirq NULL
791 #define pm_generic_restore_early NULL
792 #define pm_generic_restore NULL
793 #define pm_generic_poweroff_noirq NULL
794 #define pm_generic_poweroff_late NULL
795 #define pm_generic_poweroff NULL
796 #define pm_generic_complete NULL
797 #endif /* !CONFIG_PM_SLEEP */
798
799 /* How to reorder dpm_list after device_move() */
800 enum dpm_order {
801 DPM_ORDER_NONE,
802 DPM_ORDER_DEV_AFTER_PARENT,
803 DPM_ORDER_PARENT_BEFORE_DEV,
804 DPM_ORDER_DEV_LAST,
805 };
806
807 #endif /* _LINUX_PM_H */
808
