xref: /linux-6.15/include/linux/pm.h (revision 9ea4dcf4)
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 #ifdef CONFIG_CXL_SUSPEND
40 bool cxl_mem_active(void);
41 #else
42 static inline bool cxl_mem_active(void)
43 {
44 	return false;
45 }
46 #endif
47 
48 /*
49  * Device power management
50  */
51 
52 
53 #ifdef CONFIG_PM
54 extern const char power_group_name[];		/* = "power" */
55 #else
56 #define power_group_name	NULL
57 #endif
58 
59 typedef struct pm_message {
60 	int event;
61 } pm_message_t;
62 
63 /**
64  * struct dev_pm_ops - device PM callbacks.
65  *
66  * @prepare: The principal role of this callback is to prevent new children of
67  *	the device from being registered after it has returned (the driver's
68  *	subsystem and generally the rest of the kernel is supposed to prevent
69  *	new calls to the probe method from being made too once @prepare() has
70  *	succeeded).  If @prepare() detects a situation it cannot handle (e.g.
71  *	registration of a child already in progress), it may return -EAGAIN, so
72  *	that the PM core can execute it once again (e.g. after a new child has
73  *	been registered) to recover from the race condition.
74  *	This method is executed for all kinds of suspend transitions and is
75  *	followed by one of the suspend callbacks: @suspend(), @freeze(), or
76  *	@poweroff().  If the transition is a suspend to memory or standby (that
77  *	is, not related to hibernation), the return value of @prepare() may be
78  *	used to indicate to the PM core to leave the device in runtime suspend
79  *	if applicable.  Namely, if @prepare() returns a positive number, the PM
80  *	core will understand that as a declaration that the device appears to be
81  *	runtime-suspended and it may be left in that state during the entire
82  *	transition and during the subsequent resume if all of its descendants
83  *	are left in runtime suspend too.  If that happens, @complete() will be
84  *	executed directly after @prepare() and it must ensure the proper
85  *	functioning of the device after the system resume.
86  *	The PM core executes subsystem-level @prepare() for all devices before
87  *	starting to invoke suspend callbacks for any of them, so generally
88  *	devices may be assumed to be functional or to respond to runtime resume
89  *	requests while @prepare() is being executed.  However, device drivers
90  *	may NOT assume anything about the availability of user space at that
91  *	time and it is NOT valid to request firmware from within @prepare()
92  *	(it's too late to do that).  It also is NOT valid to allocate
93  *	substantial amounts of memory from @prepare() in the GFP_KERNEL mode.
94  *	[To work around these limitations, drivers may register suspend and
95  *	hibernation notifiers to be executed before the freezing of tasks.]
96  *
97  * @complete: Undo the changes made by @prepare().  This method is executed for
98  *	all kinds of resume transitions, following one of the resume callbacks:
99  *	@resume(), @thaw(), @restore().  Also called if the state transition
100  *	fails before the driver's suspend callback: @suspend(), @freeze() or
101  *	@poweroff(), can be executed (e.g. if the suspend callback fails for one
102  *	of the other devices that the PM core has unsuccessfully attempted to
103  *	suspend earlier).
104  *	The PM core executes subsystem-level @complete() after it has executed
105  *	the appropriate resume callbacks for all devices.  If the corresponding
106  *	@prepare() at the beginning of the suspend transition returned a
107  *	positive number and the device was left in runtime suspend (without
108  *	executing any suspend and resume callbacks for it), @complete() will be
109  *	the only callback executed for the device during resume.  In that case,
110  *	@complete() must be prepared to do whatever is necessary to ensure the
111  *	proper functioning of the device after the system resume.  To this end,
112  *	@complete() can check the power.direct_complete flag of the device to
113  *	learn whether (unset) or not (set) the previous suspend and resume
114  *	callbacks have been executed for it.
115  *
116  * @suspend: Executed before putting the system into a sleep state in which the
117  *	contents of main memory are preserved.  The exact action to perform
118  *	depends on the device's subsystem (PM domain, device type, class or bus
119  *	type), but generally the device must be quiescent after subsystem-level
120  *	@suspend() has returned, so that it doesn't do any I/O or DMA.
121  *	Subsystem-level @suspend() is executed for all devices after invoking
122  *	subsystem-level @prepare() for all of them.
123  *
124  * @suspend_late: Continue operations started by @suspend().  For a number of
125  *	devices @suspend_late() may point to the same callback routine as the
126  *	runtime suspend callback.
127  *
128  * @resume: Executed after waking the system up from a sleep state in which the
129  *	contents of main memory were preserved.  The exact action to perform
130  *	depends on the device's subsystem, but generally the driver is expected
131  *	to start working again, responding to hardware events and software
132  *	requests (the device itself may be left in a low-power state, waiting
133  *	for a runtime resume to occur).  The state of the device at the time its
134  *	driver's @resume() callback is run depends on the platform and subsystem
135  *	the device belongs to.  On most platforms, there are no restrictions on
136  *	availability of resources like clocks during @resume().
137  *	Subsystem-level @resume() is executed for all devices after invoking
138  *	subsystem-level @resume_noirq() for all of them.
139  *
140  * @resume_early: Prepare to execute @resume().  For a number of devices
141  *	@resume_early() may point to the same callback routine as the runtime
142  *	resume callback.
143  *
144  * @freeze: Hibernation-specific, executed before creating a hibernation image.
145  *	Analogous to @suspend(), but it should not enable the device to signal
146  *	wakeup events or change its power state.  The majority of subsystems
147  *	(with the notable exception of the PCI bus type) expect the driver-level
148  *	@freeze() to save the device settings in memory to be used by @restore()
149  *	during the subsequent resume from hibernation.
150  *	Subsystem-level @freeze() is executed for all devices after invoking
151  *	subsystem-level @prepare() for all of them.
152  *
153  * @freeze_late: Continue operations started by @freeze().  Analogous to
154  *	@suspend_late(), but it should not enable the device to signal wakeup
155  *	events or change its power state.
156  *
157  * @thaw: Hibernation-specific, executed after creating a hibernation image OR
158  *	if the creation of an image has failed.  Also executed after a failing
159  *	attempt to restore the contents of main memory from such an image.
160  *	Undo the changes made by the preceding @freeze(), so the device can be
161  *	operated in the same way as immediately before the call to @freeze().
162  *	Subsystem-level @thaw() is executed for all devices after invoking
163  *	subsystem-level @thaw_noirq() for all of them.  It also may be executed
164  *	directly after @freeze() in case of a transition error.
165  *
166  * @thaw_early: Prepare to execute @thaw().  Undo the changes made by the
167  *	preceding @freeze_late().
168  *
169  * @poweroff: Hibernation-specific, executed after saving a hibernation image.
170  *	Analogous to @suspend(), but it need not save the device's settings in
171  *	memory.
172  *	Subsystem-level @poweroff() is executed for all devices after invoking
173  *	subsystem-level @prepare() for all of them.
174  *
175  * @poweroff_late: Continue operations started by @poweroff().  Analogous to
176  *	@suspend_late(), but it need not save the device's settings in memory.
177  *
178  * @restore: Hibernation-specific, executed after restoring the contents of main
179  *	memory from a hibernation image, analogous to @resume().
180  *
181  * @restore_early: Prepare to execute @restore(), analogous to @resume_early().
182  *
183  * @suspend_noirq: Complete the actions started by @suspend().  Carry out any
184  *	additional operations required for suspending the device that might be
185  *	racing with its driver's interrupt handler, which is guaranteed not to
186  *	run while @suspend_noirq() is being executed.
187  *	It generally is expected that the device will be in a low-power state
188  *	(appropriate for the target system sleep state) after subsystem-level
189  *	@suspend_noirq() has returned successfully.  If the device can generate
190  *	system wakeup signals and is enabled to wake up the system, it should be
191  *	configured to do so at that time.  However, depending on the platform
192  *	and device's subsystem, @suspend() or @suspend_late() may be allowed to
193  *	put the device into the low-power state and configure it to generate
194  *	wakeup signals, in which case it generally is not necessary to define
195  *	@suspend_noirq().
196  *
197  * @resume_noirq: Prepare for the execution of @resume() by carrying out any
198  *	operations required for resuming the device that might be racing with
199  *	its driver's interrupt handler, which is guaranteed not to run while
200  *	@resume_noirq() is being executed.
201  *
202  * @freeze_noirq: Complete the actions started by @freeze().  Carry out any
203  *	additional operations required for freezing the device that might be
204  *	racing with its driver's interrupt handler, which is guaranteed not to
205  *	run while @freeze_noirq() is being executed.
206  *	The power state of the device should not be changed by either @freeze(),
207  *	or @freeze_late(), or @freeze_noirq() and it should not be configured to
208  *	signal system wakeup by any of these callbacks.
209  *
210  * @thaw_noirq: Prepare for the execution of @thaw() by carrying out any
211  *	operations required for thawing the device that might be racing with its
212  *	driver's interrupt handler, which is guaranteed not to run while
213  *	@thaw_noirq() is being executed.
214  *
215  * @poweroff_noirq: Complete the actions started by @poweroff().  Analogous to
216  *	@suspend_noirq(), but it need not save the device's settings in memory.
217  *
218  * @restore_noirq: Prepare for the execution of @restore() by carrying out any
219  *	operations required for thawing the device that might be racing with its
220  *	driver's interrupt handler, which is guaranteed not to run while
221  *	@restore_noirq() is being executed.  Analogous to @resume_noirq().
222  *
223  * @runtime_suspend: Prepare the device for a condition in which it won't be
224  *	able to communicate with the CPU(s) and RAM due to power management.
225  *	This need not mean that the device should be put into a low-power state.
226  *	For example, if the device is behind a link which is about to be turned
227  *	off, the device may remain at full power.  If the device does go to low
228  *	power and is capable of generating runtime wakeup events, remote wakeup
229  *	(i.e., a hardware mechanism allowing the device to request a change of
230  *	its power state via an interrupt) should be enabled for it.
231  *
232  * @runtime_resume: Put the device into the fully active state in response to a
233  *	wakeup event generated by hardware or at the request of software.  If
234  *	necessary, put the device into the full-power state and restore its
235  *	registers, so that it is fully operational.
236  *
237  * @runtime_idle: Device appears to be inactive and it might be put into a
238  *	low-power state if all of the necessary conditions are satisfied.
239  *	Check these conditions, and return 0 if it's appropriate to let the PM
240  *	core queue a suspend request for the device.
241  *
242  * Several device power state transitions are externally visible, affecting
243  * the state of pending I/O queues and (for drivers that touch hardware)
244  * interrupts, wakeups, DMA, and other hardware state.  There may also be
245  * internal transitions to various low-power modes which are transparent
246  * to the rest of the driver stack (such as a driver that's ON gating off
247  * clocks which are not in active use).
248  *
249  * The externally visible transitions are handled with the help of callbacks
250  * included in this structure in such a way that, typically, two levels of
251  * callbacks are involved.  First, the PM core executes callbacks provided by PM
252  * domains, device types, classes and bus types.  They are the subsystem-level
253  * callbacks expected to execute callbacks provided by device drivers, although
254  * they may choose not to do that.  If the driver callbacks are executed, they
255  * have to collaborate with the subsystem-level callbacks to achieve the goals
256  * appropriate for the given system transition, given transition phase and the
257  * subsystem the device belongs to.
258  *
259  * All of the above callbacks, except for @complete(), return error codes.
260  * However, the error codes returned by @resume(), @thaw(), @restore(),
261  * @resume_noirq(), @thaw_noirq(), and @restore_noirq(), do not cause the PM
262  * core to abort the resume transition during which they are returned.  The
263  * error codes returned in those cases are only printed to the system logs for
264  * debugging purposes.  Still, it is recommended that drivers only return error
265  * codes from their resume methods in case of an unrecoverable failure (i.e.
266  * when the device being handled refuses to resume and becomes unusable) to
267  * allow the PM core to be modified in the future, so that it can avoid
268  * attempting to handle devices that failed to resume and their children.
269  *
270  * It is allowed to unregister devices while the above callbacks are being
271  * executed.  However, a callback routine MUST NOT try to unregister the device
272  * it was called for, although it may unregister children of that device (for
273  * example, if it detects that a child was unplugged while the system was
274  * asleep).
275  *
276  * There also are callbacks related to runtime power management of devices.
277  * Again, as a rule these callbacks are executed by the PM core for subsystems
278  * (PM domains, device types, classes and bus types) and the subsystem-level
279  * callbacks are expected to invoke the driver callbacks.  Moreover, the exact
280  * actions to be performed by a device driver's callbacks generally depend on
281  * the platform and subsystem the device belongs to.
282  *
283  * Refer to Documentation/power/runtime_pm.rst for more information about the
284  * role of the @runtime_suspend(), @runtime_resume() and @runtime_idle()
285  * callbacks in device runtime power management.
286  */
287 struct dev_pm_ops {
288 	int (*prepare)(struct device *dev);
289 	void (*complete)(struct device *dev);
290 	int (*suspend)(struct device *dev);
291 	int (*resume)(struct device *dev);
292 	int (*freeze)(struct device *dev);
293 	int (*thaw)(struct device *dev);
294 	int (*poweroff)(struct device *dev);
295 	int (*restore)(struct device *dev);
296 	int (*suspend_late)(struct device *dev);
297 	int (*resume_early)(struct device *dev);
298 	int (*freeze_late)(struct device *dev);
299 	int (*thaw_early)(struct device *dev);
300 	int (*poweroff_late)(struct device *dev);
301 	int (*restore_early)(struct device *dev);
302 	int (*suspend_noirq)(struct device *dev);
303 	int (*resume_noirq)(struct device *dev);
304 	int (*freeze_noirq)(struct device *dev);
305 	int (*thaw_noirq)(struct device *dev);
306 	int (*poweroff_noirq)(struct device *dev);
307 	int (*restore_noirq)(struct device *dev);
308 	int (*runtime_suspend)(struct device *dev);
309 	int (*runtime_resume)(struct device *dev);
310 	int (*runtime_idle)(struct device *dev);
311 };
312 
313 #define SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
314 	.suspend = pm_sleep_ptr(suspend_fn), \
315 	.resume = pm_sleep_ptr(resume_fn), \
316 	.freeze = pm_sleep_ptr(suspend_fn), \
317 	.thaw = pm_sleep_ptr(resume_fn), \
318 	.poweroff = pm_sleep_ptr(suspend_fn), \
319 	.restore = pm_sleep_ptr(resume_fn),
320 
321 #define LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
322 	.suspend_late = pm_sleep_ptr(suspend_fn), \
323 	.resume_early = pm_sleep_ptr(resume_fn), \
324 	.freeze_late = pm_sleep_ptr(suspend_fn), \
325 	.thaw_early = pm_sleep_ptr(resume_fn), \
326 	.poweroff_late = pm_sleep_ptr(suspend_fn), \
327 	.restore_early = pm_sleep_ptr(resume_fn),
328 
329 #define NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
330 	.suspend_noirq = pm_sleep_ptr(suspend_fn), \
331 	.resume_noirq = pm_sleep_ptr(resume_fn), \
332 	.freeze_noirq = pm_sleep_ptr(suspend_fn), \
333 	.thaw_noirq = pm_sleep_ptr(resume_fn), \
334 	.poweroff_noirq = pm_sleep_ptr(suspend_fn), \
335 	.restore_noirq = pm_sleep_ptr(resume_fn),
336 
337 #define RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
338 	.runtime_suspend = suspend_fn, \
339 	.runtime_resume = resume_fn, \
340 	.runtime_idle = idle_fn,
341 
342 #ifdef CONFIG_PM_SLEEP
343 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
344 	SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
345 #else
346 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
347 #endif
348 
349 #ifdef CONFIG_PM_SLEEP
350 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
351 	LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
352 #else
353 #define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
354 #endif
355 
356 #ifdef CONFIG_PM_SLEEP
357 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
358 	NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
359 #else
360 #define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
361 #endif
362 
363 #ifdef CONFIG_PM
364 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
365 	RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
366 #else
367 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
368 #endif
369 
370 #define _DEFINE_DEV_PM_OPS(name, \
371 			   suspend_fn, resume_fn, \
372 			   runtime_suspend_fn, runtime_resume_fn, idle_fn) \
373 const struct dev_pm_ops name = { \
374 	SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
375 	RUNTIME_PM_OPS(runtime_suspend_fn, runtime_resume_fn, idle_fn) \
376 }
377 
378 #ifdef CONFIG_PM
379 #define _EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, runtime_suspend_fn, \
380 			   runtime_resume_fn, idle_fn, sec) \
381 	_DEFINE_DEV_PM_OPS(name, suspend_fn, resume_fn, runtime_suspend_fn, \
382 			   runtime_resume_fn, idle_fn); \
383 	_EXPORT_SYMBOL(name, sec)
384 #else
385 #define _EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, runtime_suspend_fn, \
386 			   runtime_resume_fn, idle_fn, sec) \
387 static __maybe_unused _DEFINE_DEV_PM_OPS(__static_##name, suspend_fn, \
388 					 resume_fn, runtime_suspend_fn, \
389 					 runtime_resume_fn, idle_fn)
390 #endif
391 
392 /*
393  * Use this if you want to use the same suspend and resume callbacks for suspend
394  * to RAM and hibernation.
395  *
396  * If the underlying dev_pm_ops struct symbol has to be exported, use
397  * EXPORT_SIMPLE_DEV_PM_OPS() or EXPORT_GPL_SIMPLE_DEV_PM_OPS() instead.
398  */
399 #define DEFINE_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
400 	_DEFINE_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL)
401 
402 #define EXPORT_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
403 	_EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL, "")
404 #define EXPORT_GPL_SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
405 	_EXPORT_DEV_PM_OPS(name, suspend_fn, resume_fn, NULL, NULL, NULL, "_gpl")
406 
407 /* Deprecated. Use DEFINE_SIMPLE_DEV_PM_OPS() instead. */
408 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
409 const struct dev_pm_ops __maybe_unused name = { \
410 	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
411 }
412 
413 /*
414  * Use this for defining a set of PM operations to be used in all situations
415  * (system suspend, hibernation or runtime PM).
416  * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
417  * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
418  * and .runtime_resume(), because .runtime_suspend() always works on an already
419  * quiescent device, while .suspend() should assume that the device may be doing
420  * something when it is called (it should ensure that the device will be
421  * quiescent after it has returned).  Therefore it's better to point the "late"
422  * suspend and "early" resume callback pointers, .suspend_late() and
423  * .resume_early(), to the same routines as .runtime_suspend() and
424  * .runtime_resume(), respectively (and analogously for hibernation).
425  *
426  * Deprecated. You most likely don't want this macro. Use
427  * DEFINE_RUNTIME_DEV_PM_OPS() instead.
428  */
429 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
430 const struct dev_pm_ops __maybe_unused name = { \
431 	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
432 	SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
433 }
434 
435 #define pm_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM), (_ptr))
436 #define pm_sleep_ptr(_ptr) PTR_IF(IS_ENABLED(CONFIG_PM_SLEEP), (_ptr))
437 
438 /*
439  * PM_EVENT_ messages
440  *
441  * The following PM_EVENT_ messages are defined for the internal use of the PM
442  * core, in order to provide a mechanism allowing the high level suspend and
443  * hibernation code to convey the necessary information to the device PM core
444  * code:
445  *
446  * ON		No transition.
447  *
448  * FREEZE	System is going to hibernate, call ->prepare() and ->freeze()
449  *		for all devices.
450  *
451  * SUSPEND	System is going to suspend, call ->prepare() and ->suspend()
452  *		for all devices.
453  *
454  * HIBERNATE	Hibernation image has been saved, call ->prepare() and
455  *		->poweroff() for all devices.
456  *
457  * QUIESCE	Contents of main memory are going to be restored from a (loaded)
458  *		hibernation image, call ->prepare() and ->freeze() for all
459  *		devices.
460  *
461  * RESUME	System is resuming, call ->resume() and ->complete() for all
462  *		devices.
463  *
464  * THAW		Hibernation image has been created, call ->thaw() and
465  *		->complete() for all devices.
466  *
467  * RESTORE	Contents of main memory have been restored from a hibernation
468  *		image, call ->restore() and ->complete() for all devices.
469  *
470  * RECOVER	Creation of a hibernation image or restoration of the main
471  *		memory contents from a hibernation image has failed, call
472  *		->thaw() and ->complete() for all devices.
473  *
474  * The following PM_EVENT_ messages are defined for internal use by
475  * kernel subsystems.  They are never issued by the PM core.
476  *
477  * USER_SUSPEND		Manual selective suspend was issued by userspace.
478  *
479  * USER_RESUME		Manual selective resume was issued by userspace.
480  *
481  * REMOTE_WAKEUP	Remote-wakeup request was received from the device.
482  *
483  * AUTO_SUSPEND		Automatic (device idle) runtime suspend was
484  *			initiated by the subsystem.
485  *
486  * AUTO_RESUME		Automatic (device needed) runtime resume was
487  *			requested by a driver.
488  */
489 
490 #define PM_EVENT_INVALID	(-1)
491 #define PM_EVENT_ON		0x0000
492 #define PM_EVENT_FREEZE		0x0001
493 #define PM_EVENT_SUSPEND	0x0002
494 #define PM_EVENT_HIBERNATE	0x0004
495 #define PM_EVENT_QUIESCE	0x0008
496 #define PM_EVENT_RESUME		0x0010
497 #define PM_EVENT_THAW		0x0020
498 #define PM_EVENT_RESTORE	0x0040
499 #define PM_EVENT_RECOVER	0x0080
500 #define PM_EVENT_USER		0x0100
501 #define PM_EVENT_REMOTE		0x0200
502 #define PM_EVENT_AUTO		0x0400
503 
504 #define PM_EVENT_SLEEP		(PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
505 #define PM_EVENT_USER_SUSPEND	(PM_EVENT_USER | PM_EVENT_SUSPEND)
506 #define PM_EVENT_USER_RESUME	(PM_EVENT_USER | PM_EVENT_RESUME)
507 #define PM_EVENT_REMOTE_RESUME	(PM_EVENT_REMOTE | PM_EVENT_RESUME)
508 #define PM_EVENT_AUTO_SUSPEND	(PM_EVENT_AUTO | PM_EVENT_SUSPEND)
509 #define PM_EVENT_AUTO_RESUME	(PM_EVENT_AUTO | PM_EVENT_RESUME)
510 
511 #define PMSG_INVALID	((struct pm_message){ .event = PM_EVENT_INVALID, })
512 #define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })
513 #define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })
514 #define PMSG_QUIESCE	((struct pm_message){ .event = PM_EVENT_QUIESCE, })
515 #define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
516 #define PMSG_HIBERNATE	((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
517 #define PMSG_RESUME	((struct pm_message){ .event = PM_EVENT_RESUME, })
518 #define PMSG_THAW	((struct pm_message){ .event = PM_EVENT_THAW, })
519 #define PMSG_RESTORE	((struct pm_message){ .event = PM_EVENT_RESTORE, })
520 #define PMSG_RECOVER	((struct pm_message){ .event = PM_EVENT_RECOVER, })
521 #define PMSG_USER_SUSPEND	((struct pm_message) \
522 					{ .event = PM_EVENT_USER_SUSPEND, })
523 #define PMSG_USER_RESUME	((struct pm_message) \
524 					{ .event = PM_EVENT_USER_RESUME, })
525 #define PMSG_REMOTE_RESUME	((struct pm_message) \
526 					{ .event = PM_EVENT_REMOTE_RESUME, })
527 #define PMSG_AUTO_SUSPEND	((struct pm_message) \
528 					{ .event = PM_EVENT_AUTO_SUSPEND, })
529 #define PMSG_AUTO_RESUME	((struct pm_message) \
530 					{ .event = PM_EVENT_AUTO_RESUME, })
531 
532 #define PMSG_IS_AUTO(msg)	(((msg).event & PM_EVENT_AUTO) != 0)
533 
534 /*
535  * Device run-time power management status.
536  *
537  * These status labels are used internally by the PM core to indicate the
538  * current status of a device with respect to the PM core operations.  They do
539  * not reflect the actual power state of the device or its status as seen by the
540  * driver.
541  *
542  * RPM_ACTIVE		Device is fully operational.  Indicates that the device
543  *			bus type's ->runtime_resume() callback has completed
544  *			successfully.
545  *
546  * RPM_SUSPENDED	Device bus type's ->runtime_suspend() callback has
547  *			completed successfully.  The device is regarded as
548  *			suspended.
549  *
550  * RPM_RESUMING		Device bus type's ->runtime_resume() callback is being
551  *			executed.
552  *
553  * RPM_SUSPENDING	Device bus type's ->runtime_suspend() callback is being
554  *			executed.
555  */
556 
557 enum rpm_status {
558 	RPM_INVALID = -1,
559 	RPM_ACTIVE = 0,
560 	RPM_RESUMING,
561 	RPM_SUSPENDED,
562 	RPM_SUSPENDING,
563 };
564 
565 /*
566  * Device run-time power management request types.
567  *
568  * RPM_REQ_NONE		Do nothing.
569  *
570  * RPM_REQ_IDLE		Run the device bus type's ->runtime_idle() callback
571  *
572  * RPM_REQ_SUSPEND	Run the device bus type's ->runtime_suspend() callback
573  *
574  * RPM_REQ_AUTOSUSPEND	Same as RPM_REQ_SUSPEND, but not until the device has
575  *			been inactive for as long as power.autosuspend_delay
576  *
577  * RPM_REQ_RESUME	Run the device bus type's ->runtime_resume() callback
578  */
579 
580 enum rpm_request {
581 	RPM_REQ_NONE = 0,
582 	RPM_REQ_IDLE,
583 	RPM_REQ_SUSPEND,
584 	RPM_REQ_AUTOSUSPEND,
585 	RPM_REQ_RESUME,
586 };
587 
588 struct wakeup_source;
589 struct wake_irq;
590 struct pm_domain_data;
591 
592 struct pm_subsys_data {
593 	spinlock_t lock;
594 	unsigned int refcount;
595 #ifdef CONFIG_PM_CLK
596 	unsigned int clock_op_might_sleep;
597 	struct mutex clock_mutex;
598 	struct list_head clock_list;
599 #endif
600 #ifdef CONFIG_PM_GENERIC_DOMAINS
601 	struct pm_domain_data *domain_data;
602 #endif
603 };
604 
605 /*
606  * Driver flags to control system suspend/resume behavior.
607  *
608  * These flags can be set by device drivers at the probe time.  They need not be
609  * cleared by the drivers as the driver core will take care of that.
610  *
611  * NO_DIRECT_COMPLETE: Do not apply direct-complete optimization to the device.
612  * SMART_PREPARE: Take the driver ->prepare callback return value into account.
613  * SMART_SUSPEND: Avoid resuming the device from runtime suspend.
614  * MAY_SKIP_RESUME: Allow driver "noirq" and "early" callbacks to be skipped.
615  *
616  * See Documentation/driver-api/pm/devices.rst for details.
617  */
618 #define DPM_FLAG_NO_DIRECT_COMPLETE	BIT(0)
619 #define DPM_FLAG_SMART_PREPARE		BIT(1)
620 #define DPM_FLAG_SMART_SUSPEND		BIT(2)
621 #define DPM_FLAG_MAY_SKIP_RESUME	BIT(3)
622 
623 struct dev_pm_info {
624 	pm_message_t		power_state;
625 	unsigned int		can_wakeup:1;
626 	unsigned int		async_suspend:1;
627 	bool			in_dpm_list:1;	/* Owned by the PM core */
628 	bool			is_prepared:1;	/* Owned by the PM core */
629 	bool			is_suspended:1;	/* Ditto */
630 	bool			is_noirq_suspended:1;
631 	bool			is_late_suspended:1;
632 	bool			no_pm:1;
633 	bool			early_init:1;	/* Owned by the PM core */
634 	bool			direct_complete:1;	/* Owned by the PM core */
635 	u32			driver_flags;
636 	spinlock_t		lock;
637 #ifdef CONFIG_PM_SLEEP
638 	struct list_head	entry;
639 	struct completion	completion;
640 	struct wakeup_source	*wakeup;
641 	bool			wakeup_path:1;
642 	bool			syscore:1;
643 	bool			no_pm_callbacks:1;	/* Owned by the PM core */
644 	unsigned int		must_resume:1;	/* Owned by the PM core */
645 	unsigned int		may_skip_resume:1;	/* Set by subsystems */
646 #else
647 	unsigned int		should_wakeup:1;
648 #endif
649 #ifdef CONFIG_PM
650 	struct hrtimer		suspend_timer;
651 	u64			timer_expires;
652 	struct work_struct	work;
653 	wait_queue_head_t	wait_queue;
654 	struct wake_irq		*wakeirq;
655 	atomic_t		usage_count;
656 	atomic_t		child_count;
657 	unsigned int		disable_depth:3;
658 	unsigned int		idle_notification:1;
659 	unsigned int		request_pending:1;
660 	unsigned int		deferred_resume:1;
661 	unsigned int		needs_force_resume:1;
662 	unsigned int		runtime_auto:1;
663 	bool			ignore_children:1;
664 	unsigned int		no_callbacks:1;
665 	unsigned int		irq_safe:1;
666 	unsigned int		use_autosuspend:1;
667 	unsigned int		timer_autosuspends:1;
668 	unsigned int		memalloc_noio:1;
669 	unsigned int		links_count;
670 	enum rpm_request	request;
671 	enum rpm_status		runtime_status;
672 	enum rpm_status		last_status;
673 	int			runtime_error;
674 	int			autosuspend_delay;
675 	u64			last_busy;
676 	u64			active_time;
677 	u64			suspended_time;
678 	u64			accounting_timestamp;
679 #endif
680 	struct pm_subsys_data	*subsys_data;  /* Owned by the subsystem. */
681 	void (*set_latency_tolerance)(struct device *, s32);
682 	struct dev_pm_qos	*qos;
683 };
684 
685 extern int dev_pm_get_subsys_data(struct device *dev);
686 extern void dev_pm_put_subsys_data(struct device *dev);
687 
688 /**
689  * struct dev_pm_domain - power management domain representation.
690  *
691  * @ops: Power management operations associated with this domain.
692  * @start: Called when a user needs to start the device via the domain.
693  * @detach: Called when removing a device from the domain.
694  * @activate: Called before executing probe routines for bus types and drivers.
695  * @sync: Called after successful driver probe.
696  * @dismiss: Called after unsuccessful driver probe and after driver removal.
697  *
698  * Power domains provide callbacks that are executed during system suspend,
699  * hibernation, system resume and during runtime PM transitions instead of
700  * subsystem-level and driver-level callbacks.
701  */
702 struct dev_pm_domain {
703 	struct dev_pm_ops	ops;
704 	int (*start)(struct device *dev);
705 	void (*detach)(struct device *dev, bool power_off);
706 	int (*activate)(struct device *dev);
707 	void (*sync)(struct device *dev);
708 	void (*dismiss)(struct device *dev);
709 };
710 
711 /*
712  * The PM_EVENT_ messages are also used by drivers implementing the legacy
713  * suspend framework, based on the ->suspend() and ->resume() callbacks common
714  * for suspend and hibernation transitions, according to the rules below.
715  */
716 
717 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
718 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
719 
720 /*
721  * One transition is triggered by resume(), after a suspend() call; the
722  * message is implicit:
723  *
724  * ON		Driver starts working again, responding to hardware events
725  *		and software requests.  The hardware may have gone through
726  *		a power-off reset, or it may have maintained state from the
727  *		previous suspend() which the driver will rely on while
728  *		resuming.  On most platforms, there are no restrictions on
729  *		availability of resources like clocks during resume().
730  *
731  * Other transitions are triggered by messages sent using suspend().  All
732  * these transitions quiesce the driver, so that I/O queues are inactive.
733  * That commonly entails turning off IRQs and DMA; there may be rules
734  * about how to quiesce that are specific to the bus or the device's type.
735  * (For example, network drivers mark the link state.)  Other details may
736  * differ according to the message:
737  *
738  * SUSPEND	Quiesce, enter a low power device state appropriate for
739  *		the upcoming system state (such as PCI_D3hot), and enable
740  *		wakeup events as appropriate.
741  *
742  * HIBERNATE	Enter a low power device state appropriate for the hibernation
743  *		state (eg. ACPI S4) and enable wakeup events as appropriate.
744  *
745  * FREEZE	Quiesce operations so that a consistent image can be saved;
746  *		but do NOT otherwise enter a low power device state, and do
747  *		NOT emit system wakeup events.
748  *
749  * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
750  *		the system from a snapshot taken after an earlier FREEZE.
751  *		Some drivers will need to reset their hardware state instead
752  *		of preserving it, to ensure that it's never mistaken for the
753  *		state which that earlier snapshot had set up.
754  *
755  * A minimally power-aware driver treats all messages as SUSPEND, fully
756  * reinitializes its device during resume() -- whether or not it was reset
757  * during the suspend/resume cycle -- and can't issue wakeup events.
758  *
759  * More power-aware drivers may also use low power states at runtime as
760  * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
761  * be able to use wakeup events to exit from runtime low-power states,
762  * or from system low-power states such as standby or suspend-to-RAM.
763  */
764 
765 #ifdef CONFIG_PM_SLEEP
766 extern void device_pm_lock(void);
767 extern void dpm_resume_start(pm_message_t state);
768 extern void dpm_resume_end(pm_message_t state);
769 extern void dpm_resume_noirq(pm_message_t state);
770 extern void dpm_resume_early(pm_message_t state);
771 extern void dpm_resume(pm_message_t state);
772 extern void dpm_complete(pm_message_t state);
773 
774 extern void device_pm_unlock(void);
775 extern int dpm_suspend_end(pm_message_t state);
776 extern int dpm_suspend_start(pm_message_t state);
777 extern int dpm_suspend_noirq(pm_message_t state);
778 extern int dpm_suspend_late(pm_message_t state);
779 extern int dpm_suspend(pm_message_t state);
780 extern int dpm_prepare(pm_message_t state);
781 
782 extern void __suspend_report_result(const char *function, struct device *dev, void *fn, int ret);
783 
784 #define suspend_report_result(dev, fn, ret)				\
785 	do {								\
786 		__suspend_report_result(__func__, dev, fn, ret);	\
787 	} while (0)
788 
789 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
790 extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
791 
792 extern int pm_generic_prepare(struct device *dev);
793 extern int pm_generic_suspend_late(struct device *dev);
794 extern int pm_generic_suspend_noirq(struct device *dev);
795 extern int pm_generic_suspend(struct device *dev);
796 extern int pm_generic_resume_early(struct device *dev);
797 extern int pm_generic_resume_noirq(struct device *dev);
798 extern int pm_generic_resume(struct device *dev);
799 extern int pm_generic_freeze_noirq(struct device *dev);
800 extern int pm_generic_freeze_late(struct device *dev);
801 extern int pm_generic_freeze(struct device *dev);
802 extern int pm_generic_thaw_noirq(struct device *dev);
803 extern int pm_generic_thaw_early(struct device *dev);
804 extern int pm_generic_thaw(struct device *dev);
805 extern int pm_generic_restore_noirq(struct device *dev);
806 extern int pm_generic_restore_early(struct device *dev);
807 extern int pm_generic_restore(struct device *dev);
808 extern int pm_generic_poweroff_noirq(struct device *dev);
809 extern int pm_generic_poweroff_late(struct device *dev);
810 extern int pm_generic_poweroff(struct device *dev);
811 extern void pm_generic_complete(struct device *dev);
812 
813 extern bool dev_pm_skip_resume(struct device *dev);
814 extern bool dev_pm_skip_suspend(struct device *dev);
815 
816 #else /* !CONFIG_PM_SLEEP */
817 
818 #define device_pm_lock() do {} while (0)
819 #define device_pm_unlock() do {} while (0)
820 
821 static inline int dpm_suspend_start(pm_message_t state)
822 {
823 	return 0;
824 }
825 
826 #define suspend_report_result(dev, fn, ret)	do {} while (0)
827 
828 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
829 {
830 	return 0;
831 }
832 
833 static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
834 {
835 }
836 
837 #define pm_generic_prepare		NULL
838 #define pm_generic_suspend_late		NULL
839 #define pm_generic_suspend_noirq	NULL
840 #define pm_generic_suspend		NULL
841 #define pm_generic_resume_early		NULL
842 #define pm_generic_resume_noirq		NULL
843 #define pm_generic_resume		NULL
844 #define pm_generic_freeze_noirq		NULL
845 #define pm_generic_freeze_late		NULL
846 #define pm_generic_freeze		NULL
847 #define pm_generic_thaw_noirq		NULL
848 #define pm_generic_thaw_early		NULL
849 #define pm_generic_thaw			NULL
850 #define pm_generic_restore_noirq	NULL
851 #define pm_generic_restore_early	NULL
852 #define pm_generic_restore		NULL
853 #define pm_generic_poweroff_noirq	NULL
854 #define pm_generic_poweroff_late	NULL
855 #define pm_generic_poweroff		NULL
856 #define pm_generic_complete		NULL
857 #endif /* !CONFIG_PM_SLEEP */
858 
859 /* How to reorder dpm_list after device_move() */
860 enum dpm_order {
861 	DPM_ORDER_NONE,
862 	DPM_ORDER_DEV_AFTER_PARENT,
863 	DPM_ORDER_PARENT_BEFORE_DEV,
864 	DPM_ORDER_DEV_LAST,
865 };
866 
867 #endif /* _LINUX_PM_H */
868