xref: /linux-6.15/include/linux/pm.h (revision 99fc11bb)
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
30 static inline void pm_vt_switch_required(struct device *dev, bool required)
31 {
32 }
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 #define SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
304 	.suspend = pm_sleep_ptr(suspend_fn), \
305 	.resume = pm_sleep_ptr(resume_fn), \
306 	.freeze = pm_sleep_ptr(suspend_fn), \
307 	.thaw = pm_sleep_ptr(resume_fn), \
308 	.poweroff = pm_sleep_ptr(suspend_fn), \
309 	.restore = pm_sleep_ptr(resume_fn),
310 
311 #define LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
312 	.suspend_late = pm_sleep_ptr(suspend_fn), \
313 	.resume_early = pm_sleep_ptr(resume_fn), \
314 	.freeze_late = pm_sleep_ptr(suspend_fn), \
315 	.thaw_early = pm_sleep_ptr(resume_fn), \
316 	.poweroff_late = pm_sleep_ptr(suspend_fn), \
317 	.restore_early = pm_sleep_ptr(resume_fn),
318 
319 #define NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
320 	.suspend_noirq = pm_sleep_ptr(suspend_fn), \
321 	.resume_noirq = pm_sleep_ptr(resume_fn), \
322 	.freeze_noirq = pm_sleep_ptr(suspend_fn), \
323 	.thaw_noirq = pm_sleep_ptr(resume_fn), \
324 	.poweroff_noirq = pm_sleep_ptr(suspend_fn), \
325 	.restore_noirq = pm_sleep_ptr(resume_fn),
326 
327 #define RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
328 	.runtime_suspend = suspend_fn, \
329 	.runtime_resume = resume_fn, \
330 	.runtime_idle = idle_fn,
331 
332 #ifdef CONFIG_PM_SLEEP
333 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
334 	SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
335 #else
336 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
337 #endif
338 
339 #ifdef CONFIG_PM_SLEEP
340 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
341 	LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
342 #else
343 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
344 #endif
345 
346 #ifdef CONFIG_PM_SLEEP
347 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
348 	NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
349 #else
350 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
351 #endif
352 
353 #ifdef CONFIG_PM
354 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
355 	RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
356 #else
357 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
358 #endif
359 
360 /*
361  * Use this if you want to use the same suspend and resume callbacks for suspend
362  * to RAM and hibernation.
363  */
364 #define DEFINE_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
365 static const struct dev_pm_ops name = { \
366 	SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
367 }
368 
369 /*
370  * Use this for defining a set of PM operations to be used in all situations
371  * (system suspend, hibernation or runtime PM).
372  * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
373  * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
374  * and .runtime_resume(), because .runtime_suspend() always works on an already
375  * quiescent device, while .suspend() should assume that the device may be doing
376  * something when it is called (it should ensure that the device will be
377  * quiescent after it has returned).  Therefore it's better to point the "late"
378  * suspend and "early" resume callback pointers, .suspend_late() and
379  * .resume_early(), to the same routines as .runtime_suspend() and
380  * .runtime_resume(), respectively (and analogously for hibernation).
381  */
382 #define DEFINE_UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
383 static const struct dev_pm_ops name = { \
384 	SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
385 	RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
386 }
387 
388 /* Deprecated. Use DEFINE_SIMPLE_DEV_PM_OPS() instead. */
389 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
390 const struct dev_pm_ops __maybe_unused name = { \
391 	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
392 }
393 
394 /* Deprecated. Use DEFINE_UNIVERSAL_DEV_PM_OPS() instead. */
395 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
396 const struct dev_pm_ops __maybe_unused name = { \
397 	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
398 	SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
399 }
400 
401 #define pm_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM), (_ptr))
402 #define pm_sleep_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM_SLEEP), (_ptr))
403 
404 /*
405  * PM_EVENT_ messages
406  *
407  * The following PM_EVENT_ messages are defined for the internal use of the PM
408  * core, in order to provide a mechanism allowing the high level suspend and
409  * hibernation code to convey the necessary information to the device PM core
410  * code:
411  *
412  * ON		No transition.
413  *
414  * FREEZE	System is going to hibernate, call ->prepare() and ->freeze()
415  *		for all devices.
416  *
417  * SUSPEND	System is going to suspend, call ->prepare() and ->suspend()
418  *		for all devices.
419  *
420  * HIBERNATE	Hibernation image has been saved, call ->prepare() and
421  *		->poweroff() for all devices.
422  *
423  * QUIESCE	Contents of main memory are going to be restored from a (loaded)
424  *		hibernation image, call ->prepare() and ->freeze() for all
425  *		devices.
426  *
427  * RESUME	System is resuming, call ->resume() and ->complete() for all
428  *		devices.
429  *
430  * THAW		Hibernation image has been created, call ->thaw() and
431  *		->complete() for all devices.
432  *
433  * RESTORE	Contents of main memory have been restored from a hibernation
434  *		image, call ->restore() and ->complete() for all devices.
435  *
436  * RECOVER	Creation of a hibernation image or restoration of the main
437  *		memory contents from a hibernation image has failed, call
438  *		->thaw() and ->complete() for all devices.
439  *
440  * The following PM_EVENT_ messages are defined for internal use by
441  * kernel subsystems.  They are never issued by the PM core.
442  *
443  * USER_SUSPEND		Manual selective suspend was issued by userspace.
444  *
445  * USER_RESUME		Manual selective resume was issued by userspace.
446  *
447  * REMOTE_WAKEUP	Remote-wakeup request was received from the device.
448  *
449  * AUTO_SUSPEND		Automatic (device idle) runtime suspend was
450  *			initiated by the subsystem.
451  *
452  * AUTO_RESUME		Automatic (device needed) runtime resume was
453  *			requested by a driver.
454  */
455 
456 #define PM_EVENT_INVALID	(-1)
457 #define PM_EVENT_ON		0x0000
458 #define PM_EVENT_FREEZE		0x0001
459 #define PM_EVENT_SUSPEND	0x0002
460 #define PM_EVENT_HIBERNATE	0x0004
461 #define PM_EVENT_QUIESCE	0x0008
462 #define PM_EVENT_RESUME		0x0010
463 #define PM_EVENT_THAW		0x0020
464 #define PM_EVENT_RESTORE	0x0040
465 #define PM_EVENT_RECOVER	0x0080
466 #define PM_EVENT_USER		0x0100
467 #define PM_EVENT_REMOTE		0x0200
468 #define PM_EVENT_AUTO		0x0400
469 
470 #define PM_EVENT_SLEEP		(PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
471 #define PM_EVENT_USER_SUSPEND	(PM_EVENT_USER | PM_EVENT_SUSPEND)
472 #define PM_EVENT_USER_RESUME	(PM_EVENT_USER | PM_EVENT_RESUME)
473 #define PM_EVENT_REMOTE_RESUME	(PM_EVENT_REMOTE | PM_EVENT_RESUME)
474 #define PM_EVENT_AUTO_SUSPEND	(PM_EVENT_AUTO | PM_EVENT_SUSPEND)
475 #define PM_EVENT_AUTO_RESUME	(PM_EVENT_AUTO | PM_EVENT_RESUME)
476 
477 #define PMSG_INVALID	((struct pm_message){ .event = PM_EVENT_INVALID, })
478 #define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })
479 #define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })
480 #define PMSG_QUIESCE	((struct pm_message){ .event = PM_EVENT_QUIESCE, })
481 #define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
482 #define PMSG_HIBERNATE	((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
483 #define PMSG_RESUME	((struct pm_message){ .event = PM_EVENT_RESUME, })
484 #define PMSG_THAW	((struct pm_message){ .event = PM_EVENT_THAW, })
485 #define PMSG_RESTORE	((struct pm_message){ .event = PM_EVENT_RESTORE, })
486 #define PMSG_RECOVER	((struct pm_message){ .event = PM_EVENT_RECOVER, })
487 #define PMSG_USER_SUSPEND	((struct pm_message) \
488 					{ .event = PM_EVENT_USER_SUSPEND, })
489 #define PMSG_USER_RESUME	((struct pm_message) \
490 					{ .event = PM_EVENT_USER_RESUME, })
491 #define PMSG_REMOTE_RESUME	((struct pm_message) \
492 					{ .event = PM_EVENT_REMOTE_RESUME, })
493 #define PMSG_AUTO_SUSPEND	((struct pm_message) \
494 					{ .event = PM_EVENT_AUTO_SUSPEND, })
495 #define PMSG_AUTO_RESUME	((struct pm_message) \
496 					{ .event = PM_EVENT_AUTO_RESUME, })
497 
498 #define PMSG_IS_AUTO(msg)	(((msg).event & PM_EVENT_AUTO) != 0)
499 
500 /*
501  * Device run-time power management status.
502  *
503  * These status labels are used internally by the PM core to indicate the
504  * current status of a device with respect to the PM core operations.  They do
505  * not reflect the actual power state of the device or its status as seen by the
506  * driver.
507  *
508  * RPM_ACTIVE		Device is fully operational.  Indicates that the device
509  *			bus type's ->runtime_resume() callback has completed
510  *			successfully.
511  *
512  * RPM_SUSPENDED	Device bus type's ->runtime_suspend() callback has
513  *			completed successfully.  The device is regarded as
514  *			suspended.
515  *
516  * RPM_RESUMING		Device bus type's ->runtime_resume() callback is being
517  *			executed.
518  *
519  * RPM_SUSPENDING	Device bus type's ->runtime_suspend() callback is being
520  *			executed.
521  */
522 
523 enum rpm_status {
524 	RPM_INVALID = -1,
525 	RPM_ACTIVE = 0,
526 	RPM_RESUMING,
527 	RPM_SUSPENDED,
528 	RPM_SUSPENDING,
529 };
530 
531 /*
532  * Device run-time power management request types.
533  *
534  * RPM_REQ_NONE		Do nothing.
535  *
536  * RPM_REQ_IDLE		Run the device bus type's ->runtime_idle() callback
537  *
538  * RPM_REQ_SUSPEND	Run the device bus type's ->runtime_suspend() callback
539  *
540  * RPM_REQ_AUTOSUSPEND	Same as RPM_REQ_SUSPEND, but not until the device has
541  *			been inactive for as long as power.autosuspend_delay
542  *
543  * RPM_REQ_RESUME	Run the device bus type's ->runtime_resume() callback
544  */
545 
546 enum rpm_request {
547 	RPM_REQ_NONE = 0,
548 	RPM_REQ_IDLE,
549 	RPM_REQ_SUSPEND,
550 	RPM_REQ_AUTOSUSPEND,
551 	RPM_REQ_RESUME,
552 };
553 
554 struct wakeup_source;
555 struct wake_irq;
556 struct pm_domain_data;
557 
558 struct pm_subsys_data {
559 	spinlock_t lock;
560 	unsigned int refcount;
561 #ifdef CONFIG_PM_CLK
562 	unsigned int clock_op_might_sleep;
563 	struct mutex clock_mutex;
564 	struct list_head clock_list;
565 #endif
566 #ifdef CONFIG_PM_GENERIC_DOMAINS
567 	struct pm_domain_data *domain_data;
568 #endif
569 };
570 
571 /*
572  * Driver flags to control system suspend/resume behavior.
573  *
574  * These flags can be set by device drivers at the probe time.  They need not be
575  * cleared by the drivers as the driver core will take care of that.
576  *
577  * NO_DIRECT_COMPLETE: Do not apply direct-complete optimization to the device.
578  * SMART_PREPARE: Take the driver ->prepare callback return value into account.
579  * SMART_SUSPEND: Avoid resuming the device from runtime suspend.
580  * MAY_SKIP_RESUME: Allow driver "noirq" and "early" callbacks to be skipped.
581  *
582  * See Documentation/driver-api/pm/devices.rst for details.
583  */
584 #define DPM_FLAG_NO_DIRECT_COMPLETE	BIT(0)
585 #define DPM_FLAG_SMART_PREPARE		BIT(1)
586 #define DPM_FLAG_SMART_SUSPEND		BIT(2)
587 #define DPM_FLAG_MAY_SKIP_RESUME	BIT(3)
588 
589 struct dev_pm_info {
590 	pm_message_t		power_state;
591 	unsigned int		can_wakeup:1;
592 	unsigned int		async_suspend:1;
593 	bool			in_dpm_list:1;	/* Owned by the PM core */
594 	bool			is_prepared:1;	/* Owned by the PM core */
595 	bool			is_suspended:1;	/* Ditto */
596 	bool			is_noirq_suspended:1;
597 	bool			is_late_suspended:1;
598 	bool			no_pm:1;
599 	bool			early_init:1;	/* Owned by the PM core */
600 	bool			direct_complete:1;	/* Owned by the PM core */
601 	u32			driver_flags;
602 	spinlock_t		lock;
603 #ifdef CONFIG_PM_SLEEP
604 	struct list_head	entry;
605 	struct completion	completion;
606 	struct wakeup_source	*wakeup;
607 	bool			wakeup_path:1;
608 	bool			syscore:1;
609 	bool			no_pm_callbacks:1;	/* Owned by the PM core */
610 	unsigned int		must_resume:1;	/* Owned by the PM core */
611 	unsigned int		may_skip_resume:1;	/* Set by subsystems */
612 #else
613 	unsigned int		should_wakeup:1;
614 #endif
615 #ifdef CONFIG_PM
616 	struct hrtimer		suspend_timer;
617 	u64			timer_expires;
618 	struct work_struct	work;
619 	wait_queue_head_t	wait_queue;
620 	struct wake_irq		*wakeirq;
621 	atomic_t		usage_count;
622 	atomic_t		child_count;
623 	unsigned int		disable_depth:3;
624 	unsigned int		idle_notification:1;
625 	unsigned int		request_pending:1;
626 	unsigned int		deferred_resume:1;
627 	unsigned int		needs_force_resume:1;
628 	unsigned int		runtime_auto:1;
629 	bool			ignore_children:1;
630 	unsigned int		no_callbacks:1;
631 	unsigned int		irq_safe:1;
632 	unsigned int		use_autosuspend:1;
633 	unsigned int		timer_autosuspends:1;
634 	unsigned int		memalloc_noio:1;
635 	unsigned int		links_count;
636 	enum rpm_request	request;
637 	enum rpm_status		runtime_status;
638 	enum rpm_status		last_status;
639 	int			runtime_error;
640 	int			autosuspend_delay;
641 	u64			last_busy;
642 	u64			active_time;
643 	u64			suspended_time;
644 	u64			accounting_timestamp;
645 #endif
646 	struct pm_subsys_data	*subsys_data;  /* Owned by the subsystem. */
647 	void (*set_latency_tolerance)(struct device *, s32);
648 	struct dev_pm_qos	*qos;
649 };
650 
651 extern int dev_pm_get_subsys_data(struct device *dev);
652 extern void dev_pm_put_subsys_data(struct device *dev);
653 
654 /**
655  * struct dev_pm_domain - power management domain representation.
656  *
657  * @ops: Power management operations associated with this domain.
658  * @start: Called when a user needs to start the device via the domain.
659  * @detach: Called when removing a device from the domain.
660  * @activate: Called before executing probe routines for bus types and drivers.
661  * @sync: Called after successful driver probe.
662  * @dismiss: Called after unsuccessful driver probe and after driver removal.
663  *
664  * Power domains provide callbacks that are executed during system suspend,
665  * hibernation, system resume and during runtime PM transitions instead of
666  * subsystem-level and driver-level callbacks.
667  */
668 struct dev_pm_domain {
669 	struct dev_pm_ops	ops;
670 	int (*start)(struct device *dev);
671 	void (*detach)(struct device *dev, bool power_off);
672 	int (*activate)(struct device *dev);
673 	void (*sync)(struct device *dev);
674 	void (*dismiss)(struct device *dev);
675 };
676 
677 /*
678  * The PM_EVENT_ messages are also used by drivers implementing the legacy
679  * suspend framework, based on the ->suspend() and ->resume() callbacks common
680  * for suspend and hibernation transitions, according to the rules below.
681  */
682 
683 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
684 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
685 
686 /*
687  * One transition is triggered by resume(), after a suspend() call; the
688  * message is implicit:
689  *
690  * ON		Driver starts working again, responding to hardware events
691  *		and software requests.  The hardware may have gone through
692  *		a power-off reset, or it may have maintained state from the
693  *		previous suspend() which the driver will rely on while
694  *		resuming.  On most platforms, there are no restrictions on
695  *		availability of resources like clocks during resume().
696  *
697  * Other transitions are triggered by messages sent using suspend().  All
698  * these transitions quiesce the driver, so that I/O queues are inactive.
699  * That commonly entails turning off IRQs and DMA; there may be rules
700  * about how to quiesce that are specific to the bus or the device's type.
701  * (For example, network drivers mark the link state.)  Other details may
702  * differ according to the message:
703  *
704  * SUSPEND	Quiesce, enter a low power device state appropriate for
705  *		the upcoming system state (such as PCI_D3hot), and enable
706  *		wakeup events as appropriate.
707  *
708  * HIBERNATE	Enter a low power device state appropriate for the hibernation
709  *		state (eg. ACPI S4) and enable wakeup events as appropriate.
710  *
711  * FREEZE	Quiesce operations so that a consistent image can be saved;
712  *		but do NOT otherwise enter a low power device state, and do
713  *		NOT emit system wakeup events.
714  *
715  * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
716  *		the system from a snapshot taken after an earlier FREEZE.
717  *		Some drivers will need to reset their hardware state instead
718  *		of preserving it, to ensure that it's never mistaken for the
719  *		state which that earlier snapshot had set up.
720  *
721  * A minimally power-aware driver treats all messages as SUSPEND, fully
722  * reinitializes its device during resume() -- whether or not it was reset
723  * during the suspend/resume cycle -- and can't issue wakeup events.
724  *
725  * More power-aware drivers may also use low power states at runtime as
726  * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
727  * be able to use wakeup events to exit from runtime low-power states,
728  * or from system low-power states such as standby or suspend-to-RAM.
729  */
730 
731 #ifdef CONFIG_PM_SLEEP
732 extern void device_pm_lock(void);
733 extern void dpm_resume_start(pm_message_t state);
734 extern void dpm_resume_end(pm_message_t state);
735 extern void dpm_resume_noirq(pm_message_t state);
736 extern void dpm_resume_early(pm_message_t state);
737 extern void dpm_resume(pm_message_t state);
738 extern void dpm_complete(pm_message_t state);
739 
740 extern void device_pm_unlock(void);
741 extern int dpm_suspend_end(pm_message_t state);
742 extern int dpm_suspend_start(pm_message_t state);
743 extern int dpm_suspend_noirq(pm_message_t state);
744 extern int dpm_suspend_late(pm_message_t state);
745 extern int dpm_suspend(pm_message_t state);
746 extern int dpm_prepare(pm_message_t state);
747 
748 extern void __suspend_report_result(const char *function, void *fn, int ret);
749 
750 #define suspend_report_result(fn, ret)					\
751 	do {								\
752 		__suspend_report_result(__func__, fn, ret);		\
753 	} while (0)
754 
755 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
756 extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
757 
758 extern int pm_generic_prepare(struct device *dev);
759 extern int pm_generic_suspend_late(struct device *dev);
760 extern int pm_generic_suspend_noirq(struct device *dev);
761 extern int pm_generic_suspend(struct device *dev);
762 extern int pm_generic_resume_early(struct device *dev);
763 extern int pm_generic_resume_noirq(struct device *dev);
764 extern int pm_generic_resume(struct device *dev);
765 extern int pm_generic_freeze_noirq(struct device *dev);
766 extern int pm_generic_freeze_late(struct device *dev);
767 extern int pm_generic_freeze(struct device *dev);
768 extern int pm_generic_thaw_noirq(struct device *dev);
769 extern int pm_generic_thaw_early(struct device *dev);
770 extern int pm_generic_thaw(struct device *dev);
771 extern int pm_generic_restore_noirq(struct device *dev);
772 extern int pm_generic_restore_early(struct device *dev);
773 extern int pm_generic_restore(struct device *dev);
774 extern int pm_generic_poweroff_noirq(struct device *dev);
775 extern int pm_generic_poweroff_late(struct device *dev);
776 extern int pm_generic_poweroff(struct device *dev);
777 extern void pm_generic_complete(struct device *dev);
778 
779 extern bool dev_pm_skip_resume(struct device *dev);
780 extern bool dev_pm_skip_suspend(struct device *dev);
781 
782 #else /* !CONFIG_PM_SLEEP */
783 
784 #define device_pm_lock() do {} while (0)
785 #define device_pm_unlock() do {} while (0)
786 
787 static inline int dpm_suspend_start(pm_message_t state)
788 {
789 	return 0;
790 }
791 
792 #define suspend_report_result(fn, ret)		do {} while (0)
793 
794 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
795 {
796 	return 0;
797 }
798 
799 static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
800 {
801 }
802 
803 #define pm_generic_prepare		NULL
804 #define pm_generic_suspend_late		NULL
805 #define pm_generic_suspend_noirq	NULL
806 #define pm_generic_suspend		NULL
807 #define pm_generic_resume_early		NULL
808 #define pm_generic_resume_noirq		NULL
809 #define pm_generic_resume		NULL
810 #define pm_generic_freeze_noirq		NULL
811 #define pm_generic_freeze_late		NULL
812 #define pm_generic_freeze		NULL
813 #define pm_generic_thaw_noirq		NULL
814 #define pm_generic_thaw_early		NULL
815 #define pm_generic_thaw			NULL
816 #define pm_generic_restore_noirq	NULL
817 #define pm_generic_restore_early	NULL
818 #define pm_generic_restore		NULL
819 #define pm_generic_poweroff_noirq	NULL
820 #define pm_generic_poweroff_late	NULL
821 #define pm_generic_poweroff		NULL
822 #define pm_generic_complete		NULL
823 #endif /* !CONFIG_PM_SLEEP */
824 
825 /* How to reorder dpm_list after device_move() */
826 enum dpm_order {
827 	DPM_ORDER_NONE,
828 	DPM_ORDER_DEV_AFTER_PARENT,
829 	DPM_ORDER_PARENT_BEFORE_DEV,
830 	DPM_ORDER_DEV_LAST,
831 };
832 
833 #endif /* _LINUX_PM_H */
834