xref: /linux-6.15/include/linux/pm.h (revision 0ae101fd)
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/export.h>
12 #include <linux/list.h>
13 #include <linux/workqueue.h>
14 #include <linux/spinlock.h>
15 #include <linux/wait.h>
16 #include <linux/timer.h>
17 #include <linux/hrtimer.h>
18 #include <linux/completion.h>
19 
20 /*
21  * Callbacks for platform drivers to implement.
22  */
23 extern void (*pm_power_off)(void);
24 extern void (*pm_power_off_prepare)(void);
25 
26 struct device; /* we have a circular dep with device.h */
27 #ifdef CONFIG_VT_CONSOLE_SLEEP
28 extern void pm_vt_switch_required(struct device *dev, bool required);
29 extern void pm_vt_switch_unregister(struct device *dev);
30 #else
31 static inline void pm_vt_switch_required(struct device *dev, bool required)
32 {
33 }
34 static inline void pm_vt_switch_unregister(struct device *dev)
35 {
36 }
37 #endif /* CONFIG_VT_CONSOLE_SLEEP */
38 
39 /*
40  * Device power management
41  */
42 
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 #define SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
305 	.suspend = pm_sleep_ptr(suspend_fn), \
306 	.resume = pm_sleep_ptr(resume_fn), \
307 	.freeze = pm_sleep_ptr(suspend_fn), \
308 	.thaw = pm_sleep_ptr(resume_fn), \
309 	.poweroff = pm_sleep_ptr(suspend_fn), \
310 	.restore = pm_sleep_ptr(resume_fn),
311 
312 #define LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
313 	.suspend_late = pm_sleep_ptr(suspend_fn), \
314 	.resume_early = pm_sleep_ptr(resume_fn), \
315 	.freeze_late = pm_sleep_ptr(suspend_fn), \
316 	.thaw_early = pm_sleep_ptr(resume_fn), \
317 	.poweroff_late = pm_sleep_ptr(suspend_fn), \
318 	.restore_early = pm_sleep_ptr(resume_fn),
319 
320 #define NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
321 	.suspend_noirq = pm_sleep_ptr(suspend_fn), \
322 	.resume_noirq = pm_sleep_ptr(resume_fn), \
323 	.freeze_noirq = pm_sleep_ptr(suspend_fn), \
324 	.thaw_noirq = pm_sleep_ptr(resume_fn), \
325 	.poweroff_noirq = pm_sleep_ptr(suspend_fn), \
326 	.restore_noirq = pm_sleep_ptr(resume_fn),
327 
328 #define RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
329 	.runtime_suspend = suspend_fn, \
330 	.runtime_resume = resume_fn, \
331 	.runtime_idle = idle_fn,
332 
333 #ifdef CONFIG_PM_SLEEP
334 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
335 	SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
336 #else
337 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
338 #endif
339 
340 #ifdef CONFIG_PM_SLEEP
341 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
342 	LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
343 #else
344 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
345 #endif
346 
347 #ifdef CONFIG_PM_SLEEP
348 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
349 	NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
350 #else
351 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
352 #endif
353 
354 #ifdef CONFIG_PM
355 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
356 	RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
357 #else
358 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
359 #endif
360 
361 #define _DEFINE_DEV_PM_OPS(name, \
362 			   suspend_fn, resume_fn, \
363 			   runtime_suspend_fn, runtime_resume_fn, idle_fn) \
364 const struct dev_pm_ops name = { \
365 	SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
366 	RUNTIME_PM_OPS(runtime_suspend_fn, runtime_resume_fn, idle_fn) \
367 }
368 
369 #ifdef CONFIG_PM
370 #define _EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, runtime_suspend_fn, \
371 			   runtime_resume_fn, idle_fn, sec) \
372 	_DEFINE_DEV_PM_OPS(name, suspend_fn, resume_fn, runtime_suspend_fn, \
373 			   runtime_resume_fn, idle_fn); \
374 	_EXPORT_SYMBOL(name, sec)
375 #else
376 #define _EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, runtime_suspend_fn, \
377 			   runtime_resume_fn, idle_fn, sec) \
378 static __maybe_unused _DEFINE_DEV_PM_OPS(__static_##name, suspend_fn, \
379 					 resume_fn, runtime_suspend_fn, \
380 					 runtime_resume_fn, idle_fn)
381 #endif
382 
383 /*
384  * Use this if you want to use the same suspend and resume callbacks for suspend
385  * to RAM and hibernation.
386  *
387  * If the underlying dev_pm_ops struct symbol has to be exported, use
388  * EXPORT_SIMPLE_DEV_PM_OPS() or EXPORT_GPL_SIMPLE_DEV_PM_OPS() instead.
389  */
390 #define DEFINE_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
391 	_DEFINE_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL)
392 
393 #define EXPORT_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
394 	_EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL, "")
395 #define EXPORT_GPL_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
396 	_EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL, "_gpl")
397 
398 /* Deprecated. Use DEFINE_SIMPLE_DEV_PM_OPS() instead. */
399 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
400 const struct dev_pm_ops __maybe_unused name = { \
401 	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
402 }
403 
404 /*
405  * Use this for defining a set of PM operations to be used in all situations
406  * (system suspend, hibernation or runtime PM).
407  * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
408  * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
409  * and .runtime_resume(), because .runtime_suspend() always works on an already
410  * quiescent device, while .suspend() should assume that the device may be doing
411  * something when it is called (it should ensure that the device will be
412  * quiescent after it has returned).  Therefore it's better to point the "late"
413  * suspend and "early" resume callback pointers, .suspend_late() and
414  * .resume_early(), to the same routines as .runtime_suspend() and
415  * .runtime_resume(), respectively (and analogously for hibernation).
416  *
417  * Deprecated. You most likely don't want this macro.
418  */
419 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
420 const struct dev_pm_ops __maybe_unused name = { \
421 	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
422 	SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
423 }
424 
425 #define pm_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM), (_ptr))
426 #define pm_sleep_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM_SLEEP), (_ptr))
427 
428 /*
429  * PM_EVENT_ messages
430  *
431  * The following PM_EVENT_ messages are defined for the internal use of the PM
432  * core, in order to provide a mechanism allowing the high level suspend and
433  * hibernation code to convey the necessary information to the device PM core
434  * code:
435  *
436  * ON		No transition.
437  *
438  * FREEZE	System is going to hibernate, call ->prepare() and ->freeze()
439  *		for all devices.
440  *
441  * SUSPEND	System is going to suspend, call ->prepare() and ->suspend()
442  *		for all devices.
443  *
444  * HIBERNATE	Hibernation image has been saved, call ->prepare() and
445  *		->poweroff() for all devices.
446  *
447  * QUIESCE	Contents of main memory are going to be restored from a (loaded)
448  *		hibernation image, call ->prepare() and ->freeze() for all
449  *		devices.
450  *
451  * RESUME	System is resuming, call ->resume() and ->complete() for all
452  *		devices.
453  *
454  * THAW		Hibernation image has been created, call ->thaw() and
455  *		->complete() for all devices.
456  *
457  * RESTORE	Contents of main memory have been restored from a hibernation
458  *		image, call ->restore() and ->complete() for all devices.
459  *
460  * RECOVER	Creation of a hibernation image or restoration of the main
461  *		memory contents from a hibernation image has failed, call
462  *		->thaw() and ->complete() for all devices.
463  *
464  * The following PM_EVENT_ messages are defined for internal use by
465  * kernel subsystems.  They are never issued by the PM core.
466  *
467  * USER_SUSPEND		Manual selective suspend was issued by userspace.
468  *
469  * USER_RESUME		Manual selective resume was issued by userspace.
470  *
471  * REMOTE_WAKEUP	Remote-wakeup request was received from the device.
472  *
473  * AUTO_SUSPEND		Automatic (device idle) runtime suspend was
474  *			initiated by the subsystem.
475  *
476  * AUTO_RESUME		Automatic (device needed) runtime resume was
477  *			requested by a driver.
478  */
479 
480 #define PM_EVENT_INVALID	(-1)
481 #define PM_EVENT_ON		0x0000
482 #define PM_EVENT_FREEZE		0x0001
483 #define PM_EVENT_SUSPEND	0x0002
484 #define PM_EVENT_HIBERNATE	0x0004
485 #define PM_EVENT_QUIESCE	0x0008
486 #define PM_EVENT_RESUME		0x0010
487 #define PM_EVENT_THAW		0x0020
488 #define PM_EVENT_RESTORE	0x0040
489 #define PM_EVENT_RECOVER	0x0080
490 #define PM_EVENT_USER		0x0100
491 #define PM_EVENT_REMOTE		0x0200
492 #define PM_EVENT_AUTO		0x0400
493 
494 #define PM_EVENT_SLEEP		(PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
495 #define PM_EVENT_USER_SUSPEND	(PM_EVENT_USER | PM_EVENT_SUSPEND)
496 #define PM_EVENT_USER_RESUME	(PM_EVENT_USER | PM_EVENT_RESUME)
497 #define PM_EVENT_REMOTE_RESUME	(PM_EVENT_REMOTE | PM_EVENT_RESUME)
498 #define PM_EVENT_AUTO_SUSPEND	(PM_EVENT_AUTO | PM_EVENT_SUSPEND)
499 #define PM_EVENT_AUTO_RESUME	(PM_EVENT_AUTO | PM_EVENT_RESUME)
500 
501 #define PMSG_INVALID	((struct pm_message){ .event = PM_EVENT_INVALID, })
502 #define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })
503 #define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })
504 #define PMSG_QUIESCE	((struct pm_message){ .event = PM_EVENT_QUIESCE, })
505 #define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
506 #define PMSG_HIBERNATE	((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
507 #define PMSG_RESUME	((struct pm_message){ .event = PM_EVENT_RESUME, })
508 #define PMSG_THAW	((struct pm_message){ .event = PM_EVENT_THAW, })
509 #define PMSG_RESTORE	((struct pm_message){ .event = PM_EVENT_RESTORE, })
510 #define PMSG_RECOVER	((struct pm_message){ .event = PM_EVENT_RECOVER, })
511 #define PMSG_USER_SUSPEND	((struct pm_message) \
512 					{ .event = PM_EVENT_USER_SUSPEND, })
513 #define PMSG_USER_RESUME	((struct pm_message) \
514 					{ .event = PM_EVENT_USER_RESUME, })
515 #define PMSG_REMOTE_RESUME	((struct pm_message) \
516 					{ .event = PM_EVENT_REMOTE_RESUME, })
517 #define PMSG_AUTO_SUSPEND	((struct pm_message) \
518 					{ .event = PM_EVENT_AUTO_SUSPEND, })
519 #define PMSG_AUTO_RESUME	((struct pm_message) \
520 					{ .event = PM_EVENT_AUTO_RESUME, })
521 
522 #define PMSG_IS_AUTO(msg)	(((msg).event & PM_EVENT_AUTO) != 0)
523 
524 /*
525  * Device run-time power management status.
526  *
527  * These status labels are used internally by the PM core to indicate the
528  * current status of a device with respect to the PM core operations.  They do
529  * not reflect the actual power state of the device or its status as seen by the
530  * driver.
531  *
532  * RPM_ACTIVE		Device is fully operational.  Indicates that the device
533  *			bus type's ->runtime_resume() callback has completed
534  *			successfully.
535  *
536  * RPM_SUSPENDED	Device bus type's ->runtime_suspend() callback has
537  *			completed successfully.  The device is regarded as
538  *			suspended.
539  *
540  * RPM_RESUMING		Device bus type's ->runtime_resume() callback is being
541  *			executed.
542  *
543  * RPM_SUSPENDING	Device bus type's ->runtime_suspend() callback is being
544  *			executed.
545  */
546 
547 enum rpm_status {
548 	RPM_INVALID = -1,
549 	RPM_ACTIVE = 0,
550 	RPM_RESUMING,
551 	RPM_SUSPENDED,
552 	RPM_SUSPENDING,
553 };
554 
555 /*
556  * Device run-time power management request types.
557  *
558  * RPM_REQ_NONE		Do nothing.
559  *
560  * RPM_REQ_IDLE		Run the device bus type's ->runtime_idle() callback
561  *
562  * RPM_REQ_SUSPEND	Run the device bus type's ->runtime_suspend() callback
563  *
564  * RPM_REQ_AUTOSUSPEND	Same as RPM_REQ_SUSPEND, but not until the device has
565  *			been inactive for as long as power.autosuspend_delay
566  *
567  * RPM_REQ_RESUME	Run the device bus type's ->runtime_resume() callback
568  */
569 
570 enum rpm_request {
571 	RPM_REQ_NONE = 0,
572 	RPM_REQ_IDLE,
573 	RPM_REQ_SUSPEND,
574 	RPM_REQ_AUTOSUSPEND,
575 	RPM_REQ_RESUME,
576 };
577 
578 struct wakeup_source;
579 struct wake_irq;
580 struct pm_domain_data;
581 
582 struct pm_subsys_data {
583 	spinlock_t lock;
584 	unsigned int refcount;
585 #ifdef CONFIG_PM_CLK
586 	unsigned int clock_op_might_sleep;
587 	struct mutex clock_mutex;
588 	struct list_head clock_list;
589 #endif
590 #ifdef CONFIG_PM_GENERIC_DOMAINS
591 	struct pm_domain_data *domain_data;
592 #endif
593 };
594 
595 /*
596  * Driver flags to control system suspend/resume behavior.
597  *
598  * These flags can be set by device drivers at the probe time.  They need not be
599  * cleared by the drivers as the driver core will take care of that.
600  *
601  * NO_DIRECT_COMPLETE: Do not apply direct-complete optimization to the device.
602  * SMART_PREPARE: Take the driver ->prepare callback return value into account.
603  * SMART_SUSPEND: Avoid resuming the device from runtime suspend.
604  * MAY_SKIP_RESUME: Allow driver "noirq" and "early" callbacks to be skipped.
605  *
606  * See Documentation/driver-api/pm/devices.rst for details.
607  */
608 #define DPM_FLAG_NO_DIRECT_COMPLETE	BIT(0)
609 #define DPM_FLAG_SMART_PREPARE		BIT(1)
610 #define DPM_FLAG_SMART_SUSPEND		BIT(2)
611 #define DPM_FLAG_MAY_SKIP_RESUME	BIT(3)
612 
613 struct dev_pm_info {
614 	pm_message_t		power_state;
615 	unsigned int		can_wakeup:1;
616 	unsigned int		async_suspend:1;
617 	bool			in_dpm_list:1;	/* Owned by the PM core */
618 	bool			is_prepared:1;	/* Owned by the PM core */
619 	bool			is_suspended:1;	/* Ditto */
620 	bool			is_noirq_suspended:1;
621 	bool			is_late_suspended:1;
622 	bool			no_pm:1;
623 	bool			early_init:1;	/* Owned by the PM core */
624 	bool			direct_complete:1;	/* Owned by the PM core */
625 	u32			driver_flags;
626 	spinlock_t		lock;
627 #ifdef CONFIG_PM_SLEEP
628 	struct list_head	entry;
629 	struct completion	completion;
630 	struct wakeup_source	*wakeup;
631 	bool			wakeup_path:1;
632 	bool			syscore:1;
633 	bool			no_pm_callbacks:1;	/* Owned by the PM core */
634 	unsigned int		must_resume:1;	/* Owned by the PM core */
635 	unsigned int		may_skip_resume:1;	/* Set by subsystems */
636 #else
637 	unsigned int		should_wakeup:1;
638 #endif
639 #ifdef CONFIG_PM
640 	struct hrtimer		suspend_timer;
641 	u64			timer_expires;
642 	struct work_struct	work;
643 	wait_queue_head_t	wait_queue;
644 	struct wake_irq		*wakeirq;
645 	atomic_t		usage_count;
646 	atomic_t		child_count;
647 	unsigned int		disable_depth:3;
648 	unsigned int		idle_notification:1;
649 	unsigned int		request_pending:1;
650 	unsigned int		deferred_resume:1;
651 	unsigned int		needs_force_resume:1;
652 	unsigned int		runtime_auto:1;
653 	bool			ignore_children:1;
654 	unsigned int		no_callbacks:1;
655 	unsigned int		irq_safe:1;
656 	unsigned int		use_autosuspend:1;
657 	unsigned int		timer_autosuspends:1;
658 	unsigned int		memalloc_noio:1;
659 	unsigned int		links_count;
660 	enum rpm_request	request;
661 	enum rpm_status		runtime_status;
662 	enum rpm_status		last_status;
663 	int			runtime_error;
664 	int			autosuspend_delay;
665 	u64			last_busy;
666 	u64			active_time;
667 	u64			suspended_time;
668 	u64			accounting_timestamp;
669 #endif
670 	struct pm_subsys_data	*subsys_data;  /* Owned by the subsystem. */
671 	void (*set_latency_tolerance)(struct device *, s32);
672 	struct dev_pm_qos	*qos;
673 };
674 
675 extern int dev_pm_get_subsys_data(struct device *dev);
676 extern void dev_pm_put_subsys_data(struct device *dev);
677 
678 /**
679  * struct dev_pm_domain - power management domain representation.
680  *
681  * @ops: Power management operations associated with this domain.
682  * @start: Called when a user needs to start the device via the domain.
683  * @detach: Called when removing a device from the domain.
684  * @activate: Called before executing probe routines for bus types and drivers.
685  * @sync: Called after successful driver probe.
686  * @dismiss: Called after unsuccessful driver probe and after driver removal.
687  *
688  * Power domains provide callbacks that are executed during system suspend,
689  * hibernation, system resume and during runtime PM transitions instead of
690  * subsystem-level and driver-level callbacks.
691  */
692 struct dev_pm_domain {
693 	struct dev_pm_ops	ops;
694 	int (*start)(struct device *dev);
695 	void (*detach)(struct device *dev, bool power_off);
696 	int (*activate)(struct device *dev);
697 	void (*sync)(struct device *dev);
698 	void (*dismiss)(struct device *dev);
699 };
700 
701 /*
702  * The PM_EVENT_ messages are also used by drivers implementing the legacy
703  * suspend framework, based on the ->suspend() and ->resume() callbacks common
704  * for suspend and hibernation transitions, according to the rules below.
705  */
706 
707 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
708 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
709 
710 /*
711  * One transition is triggered by resume(), after a suspend() call; the
712  * message is implicit:
713  *
714  * ON		Driver starts working again, responding to hardware events
715  *		and software requests.  The hardware may have gone through
716  *		a power-off reset, or it may have maintained state from the
717  *		previous suspend() which the driver will rely on while
718  *		resuming.  On most platforms, there are no restrictions on
719  *		availability of resources like clocks during resume().
720  *
721  * Other transitions are triggered by messages sent using suspend().  All
722  * these transitions quiesce the driver, so that I/O queues are inactive.
723  * That commonly entails turning off IRQs and DMA; there may be rules
724  * about how to quiesce that are specific to the bus or the device's type.
725  * (For example, network drivers mark the link state.)  Other details may
726  * differ according to the message:
727  *
728  * SUSPEND	Quiesce, enter a low power device state appropriate for
729  *		the upcoming system state (such as PCI_D3hot), and enable
730  *		wakeup events as appropriate.
731  *
732  * HIBERNATE	Enter a low power device state appropriate for the hibernation
733  *		state (eg. ACPI S4) and enable wakeup events as appropriate.
734  *
735  * FREEZE	Quiesce operations so that a consistent image can be saved;
736  *		but do NOT otherwise enter a low power device state, and do
737  *		NOT emit system wakeup events.
738  *
739  * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
740  *		the system from a snapshot taken after an earlier FREEZE.
741  *		Some drivers will need to reset their hardware state instead
742  *		of preserving it, to ensure that it's never mistaken for the
743  *		state which that earlier snapshot had set up.
744  *
745  * A minimally power-aware driver treats all messages as SUSPEND, fully
746  * reinitializes its device during resume() -- whether or not it was reset
747  * during the suspend/resume cycle -- and can't issue wakeup events.
748  *
749  * More power-aware drivers may also use low power states at runtime as
750  * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
751  * be able to use wakeup events to exit from runtime low-power states,
752  * or from system low-power states such as standby or suspend-to-RAM.
753  */
754 
755 #ifdef CONFIG_PM_SLEEP
756 extern void device_pm_lock(void);
757 extern void dpm_resume_start(pm_message_t state);
758 extern void dpm_resume_end(pm_message_t state);
759 extern void dpm_resume_noirq(pm_message_t state);
760 extern void dpm_resume_early(pm_message_t state);
761 extern void dpm_resume(pm_message_t state);
762 extern void dpm_complete(pm_message_t state);
763 
764 extern void device_pm_unlock(void);
765 extern int dpm_suspend_end(pm_message_t state);
766 extern int dpm_suspend_start(pm_message_t state);
767 extern int dpm_suspend_noirq(pm_message_t state);
768 extern int dpm_suspend_late(pm_message_t state);
769 extern int dpm_suspend(pm_message_t state);
770 extern int dpm_prepare(pm_message_t state);
771 
772 extern void __suspend_report_result(const char *function, void *fn, int ret);
773 
774 #define suspend_report_result(fn, ret)					\
775 	do {								\
776 		__suspend_report_result(__func__, fn, ret);		\
777 	} while (0)
778 
779 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
780 extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
781 
782 extern int pm_generic_prepare(struct device *dev);
783 extern int pm_generic_suspend_late(struct device *dev);
784 extern int pm_generic_suspend_noirq(struct device *dev);
785 extern int pm_generic_suspend(struct device *dev);
786 extern int pm_generic_resume_early(struct device *dev);
787 extern int pm_generic_resume_noirq(struct device *dev);
788 extern int pm_generic_resume(struct device *dev);
789 extern int pm_generic_freeze_noirq(struct device *dev);
790 extern int pm_generic_freeze_late(struct device *dev);
791 extern int pm_generic_freeze(struct device *dev);
792 extern int pm_generic_thaw_noirq(struct device *dev);
793 extern int pm_generic_thaw_early(struct device *dev);
794 extern int pm_generic_thaw(struct device *dev);
795 extern int pm_generic_restore_noirq(struct device *dev);
796 extern int pm_generic_restore_early(struct device *dev);
797 extern int pm_generic_restore(struct device *dev);
798 extern int pm_generic_poweroff_noirq(struct device *dev);
799 extern int pm_generic_poweroff_late(struct device *dev);
800 extern int pm_generic_poweroff(struct device *dev);
801 extern void pm_generic_complete(struct device *dev);
802 
803 extern bool dev_pm_skip_resume(struct device *dev);
804 extern bool dev_pm_skip_suspend(struct device *dev);
805 
806 #else /* !CONFIG_PM_SLEEP */
807 
808 #define device_pm_lock() do {} while (0)
809 #define device_pm_unlock() do {} while (0)
810 
811 static inline int dpm_suspend_start(pm_message_t state)
812 {
813 	return 0;
814 }
815 
816 #define suspend_report_result(fn, ret)		do {} while (0)
817 
818 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
819 {
820 	return 0;
821 }
822 
823 static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
824 {
825 }
826 
827 #define pm_generic_prepare		NULL
828 #define pm_generic_suspend_late		NULL
829 #define pm_generic_suspend_noirq	NULL
830 #define pm_generic_suspend		NULL
831 #define pm_generic_resume_early		NULL
832 #define pm_generic_resume_noirq		NULL
833 #define pm_generic_resume		NULL
834 #define pm_generic_freeze_noirq		NULL
835 #define pm_generic_freeze_late		NULL
836 #define pm_generic_freeze		NULL
837 #define pm_generic_thaw_noirq		NULL
838 #define pm_generic_thaw_early		NULL
839 #define pm_generic_thaw			NULL
840 #define pm_generic_restore_noirq	NULL
841 #define pm_generic_restore_early	NULL
842 #define pm_generic_restore		NULL
843 #define pm_generic_poweroff_noirq	NULL
844 #define pm_generic_poweroff_late	NULL
845 #define pm_generic_poweroff		NULL
846 #define pm_generic_complete		NULL
847 #endif /* !CONFIG_PM_SLEEP */
848 
849 /* How to reorder dpm_list after device_move() */
850 enum dpm_order {
851 	DPM_ORDER_NONE,
852 	DPM_ORDER_DEV_AFTER_PARENT,
853 	DPM_ORDER_PARENT_BEFORE_DEV,
854 	DPM_ORDER_DEV_LAST,
855 };
856 
857 #endif /* _LINUX_PM_H */
858