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
43 #ifdef CONFIG_PM
44 extern const char power_group_name[]; /* = "power" */
45 #else
46 #define power_group_name NULL
47 #endif
48
49 typedef struct pm_message {
50 int event;
51 } pm_message_t;
52
53 /**
54 * struct dev_pm_ops - device PM callbacks.
55 *
56 * @prepare: The principal role of this callback is to prevent new children of
57 * the device from being registered after it has returned (the driver's
58 * subsystem and generally the rest of the kernel is supposed to prevent
59 * new calls to the probe method from being made too once @prepare() has
60 * succeeded). If @prepare() detects a situation it cannot handle (e.g.
61 * registration of a child already in progress), it may return -EAGAIN, so
62 * that the PM core can execute it once again (e.g. after a new child has
63 * been registered) to recover from the race condition.
64 * This method is executed for all kinds of suspend transitions and is
65 * followed by one of the suspend callbacks: @suspend(), @freeze(), or
66 * @poweroff(). If the transition is a suspend to memory or standby (that
67 * is, not related to hibernation), the return value of @prepare() may be
68 * used to indicate to the PM core to leave the device in runtime suspend
69 * if applicable. Namely, if @prepare() returns a positive number, the PM
70 * core will understand that as a declaration that the device appears to be
71 * runtime-suspended and it may be left in that state during the entire
72 * transition and during the subsequent resume if all of its descendants
73 * are left in runtime suspend too. If that happens, @complete() will be
74 * executed directly after @prepare() and it must ensure the proper
75 * functioning of the device after the system resume.
76 * The PM core executes subsystem-level @prepare() for all devices before
77 * starting to invoke suspend callbacks for any of them, so generally
78 * devices may be assumed to be functional or to respond to runtime resume
79 * requests while @prepare() is being executed. However, device drivers
80 * may NOT assume anything about the availability of user space at that
81 * time and it is NOT valid to request firmware from within @prepare()
82 * (it's too late to do that). It also is NOT valid to allocate
83 * substantial amounts of memory from @prepare() in the GFP_KERNEL mode.
84 * [To work around these limitations, drivers may register suspend and
85 * hibernation notifiers to be executed before the freezing of tasks.]
86 *
87 * @complete: Undo the changes made by @prepare(). This method is executed for
88 * all kinds of resume transitions, following one of the resume callbacks:
89 * @resume(), @thaw(), @restore(). Also called if the state transition
90 * fails before the driver's suspend callback: @suspend(), @freeze() or
91 * @poweroff(), can be executed (e.g. if the suspend callback fails for one
92 * of the other devices that the PM core has unsuccessfully attempted to
93 * suspend earlier).
94 * The PM core executes subsystem-level @complete() after it has executed
95 * the appropriate resume callbacks for all devices. If the corresponding
96 * @prepare() at the beginning of the suspend transition returned a
97 * positive number and the device was left in runtime suspend (without
98 * executing any suspend and resume callbacks for it), @complete() will be
99 * the only callback executed for the device during resume. In that case,
100 * @complete() must be prepared to do whatever is necessary to ensure the
101 * proper functioning of the device after the system resume. To this end,
102 * @complete() can check the power.direct_complete flag of the device to
103 * learn whether (unset) or not (set) the previous suspend and resume
104 * callbacks have been executed for it.
105 *
106 * @suspend: Executed before putting the system into a sleep state in which the
107 * contents of main memory are preserved. The exact action to perform
108 * depends on the device's subsystem (PM domain, device type, class or bus
109 * type), but generally the device must be quiescent after subsystem-level
110 * @suspend() has returned, so that it doesn't do any I/O or DMA.
111 * Subsystem-level @suspend() is executed for all devices after invoking
112 * subsystem-level @prepare() for all of them.
113 *
114 * @suspend_late: Continue operations started by @suspend(). For a number of
115 * devices @suspend_late() may point to the same callback routine as the
116 * runtime suspend callback.
117 *
118 * @resume: Executed after waking the system up from a sleep state in which the
119 * contents of main memory were preserved. The exact action to perform
120 * depends on the device's subsystem, but generally the driver is expected
121 * to start working again, responding to hardware events and software
122 * requests (the device itself may be left in a low-power state, waiting
123 * for a runtime resume to occur). The state of the device at the time its
124 * driver's @resume() callback is run depends on the platform and subsystem
125 * the device belongs to. On most platforms, there are no restrictions on
126 * availability of resources like clocks during @resume().
127 * Subsystem-level @resume() is executed for all devices after invoking
128 * subsystem-level @resume_noirq() for all of them.
129 *
130 * @resume_early: Prepare to execute @resume(). For a number of devices
131 * @resume_early() may point to the same callback routine as the runtime
132 * resume callback.
133 *
134 * @freeze: Hibernation-specific, executed before creating a hibernation image.
135 * Analogous to @suspend(), but it should not enable the device to signal
136 * wakeup events or change its power state. The majority of subsystems
137 * (with the notable exception of the PCI bus type) expect the driver-level
138 * @freeze() to save the device settings in memory to be used by @restore()
139 * during the subsequent resume from hibernation.
140 * Subsystem-level @freeze() is executed for all devices after invoking
141 * subsystem-level @prepare() for all of them.
142 *
143 * @freeze_late: Continue operations started by @freeze(). Analogous to
144 * @suspend_late(), but it should not enable the device to signal wakeup
145 * events or change its power state.
146 *
147 * @thaw: Hibernation-specific, executed after creating a hibernation image OR
148 * if the creation of an image has failed. Also executed after a failing
149 * attempt to restore the contents of main memory from such an image.
150 * Undo the changes made by the preceding @freeze(), so the device can be
151 * operated in the same way as immediately before the call to @freeze().
152 * Subsystem-level @thaw() is executed for all devices after invoking
153 * subsystem-level @thaw_noirq() for all of them. It also may be executed
154 * directly after @freeze() in case of a transition error.
155 *
156 * @thaw_early: Prepare to execute @thaw(). Undo the changes made by the
157 * preceding @freeze_late().
158 *
159 * @poweroff: Hibernation-specific, executed after saving a hibernation image.
160 * Analogous to @suspend(), but it need not save the device's settings in
161 * memory.
162 * Subsystem-level @poweroff() is executed for all devices after invoking
163 * subsystem-level @prepare() for all of them.
164 *
165 * @poweroff_late: Continue operations started by @poweroff(). Analogous to
166 * @suspend_late(), but it need not save the device's settings in memory.
167 *
168 * @restore: Hibernation-specific, executed after restoring the contents of main
169 * memory from a hibernation image, analogous to @resume().
170 *
171 * @restore_early: Prepare to execute @restore(), analogous to @resume_early().
172 *
173 * @suspend_noirq: Complete the actions started by @suspend(). Carry out any
174 * additional operations required for suspending the device that might be
175 * racing with its driver's interrupt handler, which is guaranteed not to
176 * run while @suspend_noirq() is being executed.
177 * It generally is expected that the device will be in a low-power state
178 * (appropriate for the target system sleep state) after subsystem-level
179 * @suspend_noirq() has returned successfully. If the device can generate
180 * system wakeup signals and is enabled to wake up the system, it should be
181 * configured to do so at that time. However, depending on the platform
182 * and device's subsystem, @suspend() or @suspend_late() may be allowed to
183 * put the device into the low-power state and configure it to generate
184 * wakeup signals, in which case it generally is not necessary to define
185 * @suspend_noirq().
186 *
187 * @resume_noirq: Prepare for the execution of @resume() by carrying out any
188 * operations required for resuming the device that might be racing with
189 * its driver's interrupt handler, which is guaranteed not to run while
190 * @resume_noirq() is being executed.
191 *
192 * @freeze_noirq: Complete the actions started by @freeze(). Carry out any
193 * additional operations required for freezing the device that might be
194 * racing with its driver's interrupt handler, which is guaranteed not to
195 * run while @freeze_noirq() is being executed.
196 * The power state of the device should not be changed by either @freeze(),
197 * or @freeze_late(), or @freeze_noirq() and it should not be configured to
198 * signal system wakeup by any of these callbacks.
199 *
200 * @thaw_noirq: Prepare for the execution of @thaw() by carrying out any
201 * operations required for thawing the device that might be racing with its
202 * driver's interrupt handler, which is guaranteed not to run while
203 * @thaw_noirq() is being executed.
204 *
205 * @poweroff_noirq: Complete the actions started by @poweroff(). Analogous to
206 * @suspend_noirq(), but it need not save the device's settings in memory.
207 *
208 * @restore_noirq: Prepare for the execution of @restore() by carrying out any
209 * operations required for thawing the device that might be racing with its
210 * driver's interrupt handler, which is guaranteed not to run while
211 * @restore_noirq() is being executed. Analogous to @resume_noirq().
212 *
213 * @runtime_suspend: Prepare the device for a condition in which it won't be
214 * able to communicate with the CPU(s) and RAM due to power management.
215 * This need not mean that the device should be put into a low-power state.
216 * For example, if the device is behind a link which is about to be turned
217 * off, the device may remain at full power. If the device does go to low
218 * power and is capable of generating runtime wakeup events, remote wakeup
219 * (i.e., a hardware mechanism allowing the device to request a change of
220 * its power state via an interrupt) should be enabled for it.
221 *
222 * @runtime_resume: Put the device into the fully active state in response to a
223 * wakeup event generated by hardware or at the request of software. If
224 * necessary, put the device into the full-power state and restore its
225 * registers, so that it is fully operational.
226 *
227 * @runtime_idle: Device appears to be inactive and it might be put into a
228 * low-power state if all of the necessary conditions are satisfied.
229 * Check these conditions, and return 0 if it's appropriate to let the PM
230 * core queue a suspend request for the device.
231 *
232 * Several device power state transitions are externally visible, affecting
233 * the state of pending I/O queues and (for drivers that touch hardware)
234 * interrupts, wakeups, DMA, and other hardware state. There may also be
235 * internal transitions to various low-power modes which are transparent
236 * to the rest of the driver stack (such as a driver that's ON gating off
237 * clocks which are not in active use).
238 *
239 * The externally visible transitions are handled with the help of callbacks
240 * included in this structure in such a way that, typically, two levels of
241 * callbacks are involved. First, the PM core executes callbacks provided by PM
242 * domains, device types, classes and bus types. They are the subsystem-level
243 * callbacks expected to execute callbacks provided by device drivers, although
244 * they may choose not to do that. If the driver callbacks are executed, they
245 * have to collaborate with the subsystem-level callbacks to achieve the goals
246 * appropriate for the given system transition, given transition phase and the
247 * subsystem the device belongs to.
248 *
249 * All of the above callbacks, except for @complete(), return error codes.
250 * However, the error codes returned by @resume(), @thaw(), @restore(),
251 * @resume_noirq(), @thaw_noirq(), and @restore_noirq(), do not cause the PM
252 * core to abort the resume transition during which they are returned. The
253 * error codes returned in those cases are only printed to the system logs for
254 * debugging purposes. Still, it is recommended that drivers only return error
255 * codes from their resume methods in case of an unrecoverable failure (i.e.
256 * when the device being handled refuses to resume and becomes unusable) to
257 * allow the PM core to be modified in the future, so that it can avoid
258 * attempting to handle devices that failed to resume and their children.
259 *
260 * It is allowed to unregister devices while the above callbacks are being
261 * executed. However, a callback routine MUST NOT try to unregister the device
262 * it was called for, although it may unregister children of that device (for
263 * example, if it detects that a child was unplugged while the system was
264 * asleep).
265 *
266 * There also are callbacks related to runtime power management of devices.
267 * Again, as a rule these callbacks are executed by the PM core for subsystems
268 * (PM domains, device types, classes and bus types) and the subsystem-level
269 * callbacks are expected to invoke the driver callbacks. Moreover, the exact
270 * actions to be performed by a device driver's callbacks generally depend on
271 * the platform and subsystem the device belongs to.
272 *
273 * Refer to Documentation/power/runtime_pm.rst for more information about the
274 * role of the @runtime_suspend(), @runtime_resume() and @runtime_idle()
275 * callbacks in device runtime power management.
276 */
277 struct dev_pm_ops {
278 int (*prepare)(struct device *dev);
279 void (*complete)(struct device *dev);
280 int (*suspend)(struct device *dev);
281 int (*resume)(struct device *dev);
282 int (*freeze)(struct device *dev);
283 int (*thaw)(struct device *dev);
284 int (*poweroff)(struct device *dev);
285 int (*restore)(struct device *dev);
286 int (*suspend_late)(struct device *dev);
287 int (*resume_early)(struct device *dev);
288 int (*freeze_late)(struct device *dev);
289 int (*thaw_early)(struct device *dev);
290 int (*poweroff_late)(struct device *dev);
291 int (*restore_early)(struct device *dev);
292 int (*suspend_noirq)(struct device *dev);
293 int (*resume_noirq)(struct device *dev);
294 int (*freeze_noirq)(struct device *dev);
295 int (*thaw_noirq)(struct device *dev);
296 int (*poweroff_noirq)(struct device *dev);
297 int (*restore_noirq)(struct device *dev);
298 int (*runtime_suspend)(struct device *dev);
299 int (*runtime_resume)(struct device *dev);
300 int (*runtime_idle)(struct device *dev);
301 };
302
303 #ifdef CONFIG_PM_SLEEP
304 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
305 .suspend = suspend_fn, \
306 .resume = resume_fn, \
307 .freeze = suspend_fn, \
308 .thaw = resume_fn, \
309 .poweroff = suspend_fn, \
310 .restore = resume_fn,
311 #else
312 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
313 #endif
314
315 #ifdef CONFIG_PM_SLEEP
316 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
317 .suspend_late = suspend_fn, \
318 .resume_early = resume_fn, \
319 .freeze_late = suspend_fn, \
320 .thaw_early = resume_fn, \
321 .poweroff_late = suspend_fn, \
322 .restore_early = resume_fn,
323 #else
324 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
325 #endif
326
327 #ifdef CONFIG_PM_SLEEP
328 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
329 .suspend_noirq = suspend_fn, \
330 .resume_noirq = resume_fn, \
331 .freeze_noirq = suspend_fn, \
332 .thaw_noirq = resume_fn, \
333 .poweroff_noirq = suspend_fn, \
334 .restore_noirq = resume_fn,
335 #else
336 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
337 #endif
338
339 #ifdef CONFIG_PM
340 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
341 .runtime_suspend = suspend_fn, \
342 .runtime_resume = resume_fn, \
343 .runtime_idle = idle_fn,
344 #else
345 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
346 #endif
347
348 /*
349 * Use this if you want to use the same suspend and resume callbacks for suspend
350 * to RAM and hibernation.
351 */
352 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
353 const struct dev_pm_ops __maybe_unused name = { \
354 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
355 }
356
357 /*
358 * Use this for defining a set of PM operations to be used in all situations
359 * (system suspend, hibernation or runtime PM).
360 * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
361 * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
362 * and .runtime_resume(), because .runtime_suspend() always works on an already
363 * quiescent device, while .suspend() should assume that the device may be doing
364 * something when it is called (it should ensure that the device will be
365 * quiescent after it has returned). Therefore it's better to point the "late"
366 * suspend and "early" resume callback pointers, .suspend_late() and
367 * .resume_early(), to the same routines as .runtime_suspend() and
368 * .runtime_resume(), respectively (and analogously for hibernation).
369 */
370 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
371 const struct dev_pm_ops __maybe_unused name = { \
372 SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
373 SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
374 }
375
376 #ifdef CONFIG_PM
377 #define pm_ptr(_ptr) (_ptr)
378 #else
379 #define pm_ptr(_ptr) NULL
380 #endif
381
382 /*
383 * PM_EVENT_ messages
384 *
385 * The following PM_EVENT_ messages are defined for the internal use of the PM
386 * core, in order to provide a mechanism allowing the high level suspend and
387 * hibernation code to convey the necessary information to the device PM core
388 * code:
389 *
390 * ON No transition.
391 *
392 * FREEZE System is going to hibernate, call ->prepare() and ->freeze()
393 * for all devices.
394 *
395 * SUSPEND System is going to suspend, call ->prepare() and ->suspend()
396 * for all devices.
397 *
398 * HIBERNATE Hibernation image has been saved, call ->prepare() and
399 * ->poweroff() for all devices.
400 *
401 * QUIESCE Contents of main memory are going to be restored from a (loaded)
402 * hibernation image, call ->prepare() and ->freeze() for all
403 * devices.
404 *
405 * RESUME System is resuming, call ->resume() and ->complete() for all
406 * devices.
407 *
408 * THAW Hibernation image has been created, call ->thaw() and
409 * ->complete() for all devices.
410 *
411 * RESTORE Contents of main memory have been restored from a hibernation
412 * image, call ->restore() and ->complete() for all devices.
413 *
414 * RECOVER Creation of a hibernation image or restoration of the main
415 * memory contents from a hibernation image has failed, call
416 * ->thaw() and ->complete() for all devices.
417 *
418 * The following PM_EVENT_ messages are defined for internal use by
419 * kernel subsystems. They are never issued by the PM core.
420 *
421 * USER_SUSPEND Manual selective suspend was issued by userspace.
422 *
423 * USER_RESUME Manual selective resume was issued by userspace.
424 *
425 * REMOTE_WAKEUP Remote-wakeup request was received from the device.
426 *
427 * AUTO_SUSPEND Automatic (device idle) runtime suspend was
428 * initiated by the subsystem.
429 *
430 * AUTO_RESUME Automatic (device needed) runtime resume was
431 * requested by a driver.
432 */
433
434 #define PM_EVENT_INVALID (-1)
435 #define PM_EVENT_ON 0x0000
436 #define PM_EVENT_FREEZE 0x0001
437 #define PM_EVENT_SUSPEND 0x0002
438 #define PM_EVENT_HIBERNATE 0x0004
439 #define PM_EVENT_QUIESCE 0x0008
440 #define PM_EVENT_RESUME 0x0010
441 #define PM_EVENT_THAW 0x0020
442 #define PM_EVENT_RESTORE 0x0040
443 #define PM_EVENT_RECOVER 0x0080
444 #define PM_EVENT_USER 0x0100
445 #define PM_EVENT_REMOTE 0x0200
446 #define PM_EVENT_AUTO 0x0400
447
448 #define PM_EVENT_SLEEP (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
449 #define PM_EVENT_USER_SUSPEND (PM_EVENT_USER | PM_EVENT_SUSPEND)
450 #define PM_EVENT_USER_RESUME (PM_EVENT_USER | PM_EVENT_RESUME)
451 #define PM_EVENT_REMOTE_RESUME (PM_EVENT_REMOTE | PM_EVENT_RESUME)
452 #define PM_EVENT_AUTO_SUSPEND (PM_EVENT_AUTO | PM_EVENT_SUSPEND)
453 #define PM_EVENT_AUTO_RESUME (PM_EVENT_AUTO | PM_EVENT_RESUME)
454
455 #define PMSG_INVALID ((struct pm_message){ .event = PM_EVENT_INVALID, })
456 #define PMSG_ON ((struct pm_message){ .event = PM_EVENT_ON, })
457 #define PMSG_FREEZE ((struct pm_message){ .event = PM_EVENT_FREEZE, })
458 #define PMSG_QUIESCE ((struct pm_message){ .event = PM_EVENT_QUIESCE, })
459 #define PMSG_SUSPEND ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
460 #define PMSG_HIBERNATE ((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
461 #define PMSG_RESUME ((struct pm_message){ .event = PM_EVENT_RESUME, })
462 #define PMSG_THAW ((struct pm_message){ .event = PM_EVENT_THAW, })
463 #define PMSG_RESTORE ((struct pm_message){ .event = PM_EVENT_RESTORE, })
464 #define PMSG_RECOVER ((struct pm_message){ .event = PM_EVENT_RECOVER, })
465 #define PMSG_USER_SUSPEND ((struct pm_message) \
466 { .event = PM_EVENT_USER_SUSPEND, })
467 #define PMSG_USER_RESUME ((struct pm_message) \
468 { .event = PM_EVENT_USER_RESUME, })
469 #define PMSG_REMOTE_RESUME ((struct pm_message) \
470 { .event = PM_EVENT_REMOTE_RESUME, })
471 #define PMSG_AUTO_SUSPEND ((struct pm_message) \
472 { .event = PM_EVENT_AUTO_SUSPEND, })
473 #define PMSG_AUTO_RESUME ((struct pm_message) \
474 { .event = PM_EVENT_AUTO_RESUME, })
475
476 #define PMSG_IS_AUTO(msg) (((msg).event & PM_EVENT_AUTO) != 0)
477
478 /*
479 * Device run-time power management status.
480 *
481 * These status labels are used internally by the PM core to indicate the
482 * current status of a device with respect to the PM core operations. They do
483 * not reflect the actual power state of the device or its status as seen by the
484 * driver.
485 *
486 * RPM_ACTIVE Device is fully operational. Indicates that the device
487 * bus type's ->runtime_resume() callback has completed
488 * successfully.
489 *
490 * RPM_SUSPENDED Device bus type's ->runtime_suspend() callback has
491 * completed successfully. The device is regarded as
492 * suspended.
493 *
494 * RPM_RESUMING Device bus type's ->runtime_resume() callback is being
495 * executed.
496 *
497 * RPM_SUSPENDING Device bus type's ->runtime_suspend() callback is being
498 * executed.
499 */
500
501 enum rpm_status {
502 RPM_ACTIVE = 0,
503 RPM_RESUMING,
504 RPM_SUSPENDED,
505 RPM_SUSPENDING,
506 };
507
508 /*
509 * Device run-time power management request types.
510 *
511 * RPM_REQ_NONE Do nothing.
512 *
513 * RPM_REQ_IDLE Run the device bus type's ->runtime_idle() callback
514 *
515 * RPM_REQ_SUSPEND Run the device bus type's ->runtime_suspend() callback
516 *
517 * RPM_REQ_AUTOSUSPEND Same as RPM_REQ_SUSPEND, but not until the device has
518 * been inactive for as long as power.autosuspend_delay
519 *
520 * RPM_REQ_RESUME Run the device bus type's ->runtime_resume() callback
521 */
522
523 enum rpm_request {
524 RPM_REQ_NONE = 0,
525 RPM_REQ_IDLE,
526 RPM_REQ_SUSPEND,
527 RPM_REQ_AUTOSUSPEND,
528 RPM_REQ_RESUME,
529 };
530
531 struct wakeup_source;
532 struct wake_irq;
533 struct pm_domain_data;
534
535 struct pm_subsys_data {
536 spinlock_t lock;
537 unsigned int refcount;
538 #ifdef CONFIG_PM_CLK
539 unsigned int clock_op_might_sleep;
540 struct mutex clock_mutex;
541 struct list_head clock_list;
542 #endif
543 #ifdef CONFIG_PM_GENERIC_DOMAINS
544 struct pm_domain_data *domain_data;
545 #endif
546 };
547
548 /*
549 * Driver flags to control system suspend/resume behavior.
550 *
551 * These flags can be set by device drivers at the probe time. They need not be
552 * cleared by the drivers as the driver core will take care of that.
553 *
554 * NO_DIRECT_COMPLETE: Do not apply direct-complete optimization to the device.
555 * SMART_PREPARE: Take the driver ->prepare callback return value into account.
556 * SMART_SUSPEND: Avoid resuming the device from runtime suspend.
557 * MAY_SKIP_RESUME: Allow driver "noirq" and "early" callbacks to be skipped.
558 *
559 * See Documentation/driver-api/pm/devices.rst for details.
560 */
561 #define DPM_FLAG_NO_DIRECT_COMPLETE BIT(0)
562 #define DPM_FLAG_SMART_PREPARE BIT(1)
563 #define DPM_FLAG_SMART_SUSPEND BIT(2)
564 #define DPM_FLAG_MAY_SKIP_RESUME BIT(3)
565
566 struct dev_pm_info {
567 pm_message_t power_state;
568 unsigned int can_wakeup:1;
569 unsigned int async_suspend:1;
570 bool in_dpm_list:1; /* Owned by the PM core */
571 bool is_prepared:1; /* Owned by the PM core */
572 bool is_suspended:1; /* Ditto */
573 bool is_noirq_suspended:1;
574 bool is_late_suspended:1;
575 bool no_pm:1;
576 bool early_init:1; /* Owned by the PM core */
577 bool direct_complete:1; /* Owned by the PM core */
578 u32 driver_flags;
579 spinlock_t lock;
580 #ifdef CONFIG_PM_SLEEP
581 struct list_head entry;
582 struct completion completion;
583 struct wakeup_source *wakeup;
584 bool wakeup_path:1;
585 bool syscore:1;
586 bool no_pm_callbacks:1; /* Owned by the PM core */
587 unsigned int must_resume:1; /* Owned by the PM core */
588 unsigned int may_skip_resume:1; /* Set by subsystems */
589 #else
590 unsigned int should_wakeup:1;
591 #endif
592 #ifdef CONFIG_PM
593 struct hrtimer suspend_timer;
594 u64 timer_expires;
595 struct work_struct work;
596 wait_queue_head_t wait_queue;
597 struct wake_irq *wakeirq;
598 atomic_t usage_count;
599 atomic_t child_count;
600 unsigned int disable_depth:3;
601 unsigned int idle_notification:1;
602 unsigned int request_pending:1;
603 unsigned int deferred_resume:1;
604 unsigned int needs_force_resume:1;
605 unsigned int runtime_auto:1;
606 bool ignore_children:1;
607 unsigned int no_callbacks:1;
608 unsigned int irq_safe:1;
609 unsigned int use_autosuspend:1;
610 unsigned int timer_autosuspends:1;
611 unsigned int memalloc_noio:1;
612 unsigned int links_count;
613 enum rpm_request request;
614 enum rpm_status runtime_status;
615 int runtime_error;
616 int autosuspend_delay;
617 u64 last_busy;
618 u64 active_time;
619 u64 suspended_time;
620 u64 accounting_timestamp;
621 #endif
622 struct pm_subsys_data *subsys_data; /* Owned by the subsystem. */
623 void (*set_latency_tolerance)(struct device *, s32);
624 struct dev_pm_qos *qos;
625 };
626
627 extern int dev_pm_get_subsys_data(struct device *dev);
628 extern void dev_pm_put_subsys_data(struct device *dev);
629
630 /**
631 * struct dev_pm_domain - power management domain representation.
632 *
633 * @ops: Power management operations associated with this domain.
634 * @start: Called when a user needs to start the device via the domain.
635 * @detach: Called when removing a device from the domain.
636 * @activate: Called before executing probe routines for bus types and drivers.
637 * @sync: Called after successful driver probe.
638 * @dismiss: Called after unsuccessful driver probe and after driver removal.
639 *
640 * Power domains provide callbacks that are executed during system suspend,
641 * hibernation, system resume and during runtime PM transitions instead of
642 * subsystem-level and driver-level callbacks.
643 */
644 struct dev_pm_domain {
645 struct dev_pm_ops ops;
646 int (*start)(struct device *dev);
647 void (*detach)(struct device *dev, bool power_off);
648 int (*activate)(struct device *dev);
649 void (*sync)(struct device *dev);
650 void (*dismiss)(struct device *dev);
651 };
652
653 /*
654 * The PM_EVENT_ messages are also used by drivers implementing the legacy
655 * suspend framework, based on the ->suspend() and ->resume() callbacks common
656 * for suspend and hibernation transitions, according to the rules below.
657 */
658
659 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
660 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
661
662 /*
663 * One transition is triggered by resume(), after a suspend() call; the
664 * message is implicit:
665 *
666 * ON Driver starts working again, responding to hardware events
667 * and software requests. The hardware may have gone through
668 * a power-off reset, or it may have maintained state from the
669 * previous suspend() which the driver will rely on while
670 * resuming. On most platforms, there are no restrictions on
671 * availability of resources like clocks during resume().
672 *
673 * Other transitions are triggered by messages sent using suspend(). All
674 * these transitions quiesce the driver, so that I/O queues are inactive.
675 * That commonly entails turning off IRQs and DMA; there may be rules
676 * about how to quiesce that are specific to the bus or the device's type.
677 * (For example, network drivers mark the link state.) Other details may
678 * differ according to the message:
679 *
680 * SUSPEND Quiesce, enter a low power device state appropriate for
681 * the upcoming system state (such as PCI_D3hot), and enable
682 * wakeup events as appropriate.
683 *
684 * HIBERNATE Enter a low power device state appropriate for the hibernation
685 * state (eg. ACPI S4) and enable wakeup events as appropriate.
686 *
687 * FREEZE Quiesce operations so that a consistent image can be saved;
688 * but do NOT otherwise enter a low power device state, and do
689 * NOT emit system wakeup events.
690 *
691 * PRETHAW Quiesce as if for FREEZE; additionally, prepare for restoring
692 * the system from a snapshot taken after an earlier FREEZE.
693 * Some drivers will need to reset their hardware state instead
694 * of preserving it, to ensure that it's never mistaken for the
695 * state which that earlier snapshot had set up.
696 *
697 * A minimally power-aware driver treats all messages as SUSPEND, fully
698 * reinitializes its device during resume() -- whether or not it was reset
699 * during the suspend/resume cycle -- and can't issue wakeup events.
700 *
701 * More power-aware drivers may also use low power states at runtime as
702 * well as during system sleep states like PM_SUSPEND_STANDBY. They may
703 * be able to use wakeup events to exit from runtime low-power states,
704 * or from system low-power states such as standby or suspend-to-RAM.
705 */
706
707 #ifdef CONFIG_PM_SLEEP
708 extern void device_pm_lock(void);
709 extern void dpm_resume_start(pm_message_t state);
710 extern void dpm_resume_end(pm_message_t state);
711 extern void dpm_resume_noirq(pm_message_t state);
712 extern void dpm_resume_early(pm_message_t state);
713 extern void dpm_resume(pm_message_t state);
714 extern void dpm_complete(pm_message_t state);
715
716 extern void device_pm_unlock(void);
717 extern int dpm_suspend_end(pm_message_t state);
718 extern int dpm_suspend_start(pm_message_t state);
719 extern int dpm_suspend_noirq(pm_message_t state);
720 extern int dpm_suspend_late(pm_message_t state);
721 extern int dpm_suspend(pm_message_t state);
722 extern int dpm_prepare(pm_message_t state);
723
724 extern void __suspend_report_result(const char *function, void *fn, int ret);
725
726 #define suspend_report_result(fn, ret) \
727 do { \
728 __suspend_report_result(__func__, fn, ret); \
729 } while (0)
730
731 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
732 extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
733
734 extern int pm_generic_prepare(struct device *dev);
735 extern int pm_generic_suspend_late(struct device *dev);
736 extern int pm_generic_suspend_noirq(struct device *dev);
737 extern int pm_generic_suspend(struct device *dev);
738 extern int pm_generic_resume_early(struct device *dev);
739 extern int pm_generic_resume_noirq(struct device *dev);
740 extern int pm_generic_resume(struct device *dev);
741 extern int pm_generic_freeze_noirq(struct device *dev);
742 extern int pm_generic_freeze_late(struct device *dev);
743 extern int pm_generic_freeze(struct device *dev);
744 extern int pm_generic_thaw_noirq(struct device *dev);
745 extern int pm_generic_thaw_early(struct device *dev);
746 extern int pm_generic_thaw(struct device *dev);
747 extern int pm_generic_restore_noirq(struct device *dev);
748 extern int pm_generic_restore_early(struct device *dev);
749 extern int pm_generic_restore(struct device *dev);
750 extern int pm_generic_poweroff_noirq(struct device *dev);
751 extern int pm_generic_poweroff_late(struct device *dev);
752 extern int pm_generic_poweroff(struct device *dev);
753 extern void pm_generic_complete(struct device *dev);
754
755 extern bool dev_pm_skip_resume(struct device *dev);
756 extern bool dev_pm_skip_suspend(struct device *dev);
757
758 #else /* !CONFIG_PM_SLEEP */
759
760 #define device_pm_lock() do {} while (0)
761 #define device_pm_unlock() do {} while (0)
762
dpm_suspend_start(pm_message_t state)763 static inline int dpm_suspend_start(pm_message_t state)
764 {
765 return 0;
766 }
767
768 #define suspend_report_result(fn, ret) do {} while (0)
769
device_pm_wait_for_dev(struct device * a,struct device * b)770 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
771 {
772 return 0;
773 }
774
dpm_for_each_dev(void * data,void (* fn)(struct device *,void *))775 static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
776 {
777 }
778
779 #define pm_generic_prepare NULL
780 #define pm_generic_suspend_late NULL
781 #define pm_generic_suspend_noirq NULL
782 #define pm_generic_suspend NULL
783 #define pm_generic_resume_early NULL
784 #define pm_generic_resume_noirq NULL
785 #define pm_generic_resume NULL
786 #define pm_generic_freeze_noirq NULL
787 #define pm_generic_freeze_late NULL
788 #define pm_generic_freeze NULL
789 #define pm_generic_thaw_noirq NULL
790 #define pm_generic_thaw_early NULL
791 #define pm_generic_thaw NULL
792 #define pm_generic_restore_noirq NULL
793 #define pm_generic_restore_early NULL
794 #define pm_generic_restore NULL
795 #define pm_generic_poweroff_noirq NULL
796 #define pm_generic_poweroff_late NULL
797 #define pm_generic_poweroff NULL
798 #define pm_generic_complete NULL
799 #endif /* !CONFIG_PM_SLEEP */
800
801 /* How to reorder dpm_list after device_move() */
802 enum dpm_order {
803 DPM_ORDER_NONE,
804 DPM_ORDER_DEV_AFTER_PARENT,
805 DPM_ORDER_PARENT_BEFORE_DEV,
806 DPM_ORDER_DEV_LAST,
807 };
808
809 #endif /* _LINUX_PM_H */
810