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v5.9
  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 */
 
 22extern void (*pm_power_off)(void);
 23extern void (*pm_power_off_prepare)(void);
 24
 25struct device; /* we have a circular dep with device.h */
 26#ifdef CONFIG_VT_CONSOLE_SLEEP
 27extern void pm_vt_switch_required(struct device *dev, bool required);
 28extern void pm_vt_switch_unregister(struct device *dev);
 29#else
 30static inline void pm_vt_switch_required(struct device *dev, bool required)
 31{
 32}
 33static 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
 42struct device;
 43
 44#ifdef CONFIG_PM
 45extern const char power_group_name[];		/* = "power" */
 46#else
 47#define power_group_name	NULL
 48#endif
 49
 50typedef 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 */
 
278struct dev_pm_ops {
279	int (*prepare)(struct device *dev);
280	void (*complete)(struct device *dev);
281	int (*suspend)(struct device *dev);
282	int (*resume)(struct device *dev);
283	int (*freeze)(struct device *dev);
284	int (*thaw)(struct device *dev);
285	int (*poweroff)(struct device *dev);
286	int (*restore)(struct device *dev);
287	int (*suspend_late)(struct device *dev);
288	int (*resume_early)(struct device *dev);
289	int (*freeze_late)(struct device *dev);
290	int (*thaw_early)(struct device *dev);
291	int (*poweroff_late)(struct device *dev);
292	int (*restore_early)(struct device *dev);
293	int (*suspend_noirq)(struct device *dev);
294	int (*resume_noirq)(struct device *dev);
295	int (*freeze_noirq)(struct device *dev);
296	int (*thaw_noirq)(struct device *dev);
297	int (*poweroff_noirq)(struct device *dev);
298	int (*restore_noirq)(struct device *dev);
299	int (*runtime_suspend)(struct device *dev);
300	int (*runtime_resume)(struct device *dev);
301	int (*runtime_idle)(struct device *dev);
302};
303
304#ifdef CONFIG_PM_SLEEP
305#define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
306	.suspend = suspend_fn, \
307	.resume = resume_fn, \
308	.freeze = suspend_fn, \
309	.thaw = resume_fn, \
310	.poweroff = suspend_fn, \
311	.restore = resume_fn,
312#else
313#define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
314#endif
315
316#ifdef CONFIG_PM_SLEEP
317#define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
318	.suspend_late = suspend_fn, \
319	.resume_early = resume_fn, \
320	.freeze_late = suspend_fn, \
321	.thaw_early = resume_fn, \
322	.poweroff_late = suspend_fn, \
323	.restore_early = resume_fn,
324#else
325#define SET_LATE_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
326#endif
327
328#ifdef CONFIG_PM_SLEEP
329#define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
330	.suspend_noirq = suspend_fn, \
331	.resume_noirq = resume_fn, \
332	.freeze_noirq = suspend_fn, \
333	.thaw_noirq = resume_fn, \
334	.poweroff_noirq = suspend_fn, \
335	.restore_noirq = resume_fn,
336#else
337#define SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
338#endif
339
340#ifdef CONFIG_PM
341#define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
342	.runtime_suspend = suspend_fn, \
343	.runtime_resume = resume_fn, \
344	.runtime_idle = idle_fn,
345#else
346#define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
347#endif
348
349/*
350 * Use this if you want to use the same suspend and resume callbacks for suspend
351 * to RAM and hibernation.
352 */
353#define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
354const struct dev_pm_ops __maybe_unused name = { \
355	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
356}
357
358/*
359 * Use this for defining a set of PM operations to be used in all situations
360 * (system suspend, hibernation or runtime PM).
361 * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
362 * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
363 * and .runtime_resume(), because .runtime_suspend() always works on an already
364 * quiescent device, while .suspend() should assume that the device may be doing
365 * something when it is called (it should ensure that the device will be
366 * quiescent after it has returned).  Therefore it's better to point the "late"
367 * suspend and "early" resume callback pointers, .suspend_late() and
368 * .resume_early(), to the same routines as .runtime_suspend() and
369 * .runtime_resume(), respectively (and analogously for hibernation).
370 */
371#define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
372const struct dev_pm_ops __maybe_unused name = { \
373	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
374	SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
375}
376
377#ifdef CONFIG_PM
378#define pm_ptr(_ptr) (_ptr)
379#else
380#define pm_ptr(_ptr) NULL
381#endif
382
383/*
384 * PM_EVENT_ messages
385 *
386 * The following PM_EVENT_ messages are defined for the internal use of the PM
387 * core, in order to provide a mechanism allowing the high level suspend and
388 * hibernation code to convey the necessary information to the device PM core
389 * code:
390 *
391 * ON		No transition.
392 *
393 * FREEZE	System is going to hibernate, call ->prepare() and ->freeze()
394 *		for all devices.
395 *
396 * SUSPEND	System is going to suspend, call ->prepare() and ->suspend()
397 *		for all devices.
398 *
399 * HIBERNATE	Hibernation image has been saved, call ->prepare() and
400 *		->poweroff() for all devices.
401 *
402 * QUIESCE	Contents of main memory are going to be restored from a (loaded)
403 *		hibernation image, call ->prepare() and ->freeze() for all
404 *		devices.
405 *
406 * RESUME	System is resuming, call ->resume() and ->complete() for all
407 *		devices.
408 *
409 * THAW		Hibernation image has been created, call ->thaw() and
410 *		->complete() for all devices.
411 *
412 * RESTORE	Contents of main memory have been restored from a hibernation
413 *		image, call ->restore() and ->complete() for all devices.
414 *
415 * RECOVER	Creation of a hibernation image or restoration of the main
416 *		memory contents from a hibernation image has failed, call
417 *		->thaw() and ->complete() for all devices.
418 *
419 * The following PM_EVENT_ messages are defined for internal use by
420 * kernel subsystems.  They are never issued by the PM core.
421 *
422 * USER_SUSPEND		Manual selective suspend was issued by userspace.
423 *
424 * USER_RESUME		Manual selective resume was issued by userspace.
425 *
426 * REMOTE_WAKEUP	Remote-wakeup request was received from the device.
427 *
428 * AUTO_SUSPEND		Automatic (device idle) runtime suspend was
429 *			initiated by the subsystem.
430 *
431 * AUTO_RESUME		Automatic (device needed) runtime resume was
432 *			requested by a driver.
433 */
434
435#define PM_EVENT_INVALID	(-1)
436#define PM_EVENT_ON		0x0000
437#define PM_EVENT_FREEZE		0x0001
438#define PM_EVENT_SUSPEND	0x0002
439#define PM_EVENT_HIBERNATE	0x0004
440#define PM_EVENT_QUIESCE	0x0008
441#define PM_EVENT_RESUME		0x0010
442#define PM_EVENT_THAW		0x0020
443#define PM_EVENT_RESTORE	0x0040
444#define PM_EVENT_RECOVER	0x0080
445#define PM_EVENT_USER		0x0100
446#define PM_EVENT_REMOTE		0x0200
447#define PM_EVENT_AUTO		0x0400
448
449#define PM_EVENT_SLEEP		(PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
450#define PM_EVENT_USER_SUSPEND	(PM_EVENT_USER | PM_EVENT_SUSPEND)
451#define PM_EVENT_USER_RESUME	(PM_EVENT_USER | PM_EVENT_RESUME)
452#define PM_EVENT_REMOTE_RESUME	(PM_EVENT_REMOTE | PM_EVENT_RESUME)
453#define PM_EVENT_AUTO_SUSPEND	(PM_EVENT_AUTO | PM_EVENT_SUSPEND)
454#define PM_EVENT_AUTO_RESUME	(PM_EVENT_AUTO | PM_EVENT_RESUME)
455
456#define PMSG_INVALID	((struct pm_message){ .event = PM_EVENT_INVALID, })
457#define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })
458#define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })
459#define PMSG_QUIESCE	((struct pm_message){ .event = PM_EVENT_QUIESCE, })
460#define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
461#define PMSG_HIBERNATE	((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
462#define PMSG_RESUME	((struct pm_message){ .event = PM_EVENT_RESUME, })
463#define PMSG_THAW	((struct pm_message){ .event = PM_EVENT_THAW, })
464#define PMSG_RESTORE	((struct pm_message){ .event = PM_EVENT_RESTORE, })
465#define PMSG_RECOVER	((struct pm_message){ .event = PM_EVENT_RECOVER, })
466#define PMSG_USER_SUSPEND	((struct pm_message) \
467					{ .event = PM_EVENT_USER_SUSPEND, })
468#define PMSG_USER_RESUME	((struct pm_message) \
469					{ .event = PM_EVENT_USER_RESUME, })
470#define PMSG_REMOTE_RESUME	((struct pm_message) \
471					{ .event = PM_EVENT_REMOTE_RESUME, })
472#define PMSG_AUTO_SUSPEND	((struct pm_message) \
473					{ .event = PM_EVENT_AUTO_SUSPEND, })
474#define PMSG_AUTO_RESUME	((struct pm_message) \
475					{ .event = PM_EVENT_AUTO_RESUME, })
476
477#define PMSG_IS_AUTO(msg)	(((msg).event & PM_EVENT_AUTO) != 0)
478
479/*
480 * Device run-time power management status.
481 *
482 * These status labels are used internally by the PM core to indicate the
483 * current status of a device with respect to the PM core operations.  They do
484 * not reflect the actual power state of the device or its status as seen by the
485 * driver.
486 *
487 * RPM_ACTIVE		Device is fully operational.  Indicates that the device
488 *			bus type's ->runtime_resume() callback has completed
489 *			successfully.
490 *
491 * RPM_SUSPENDED	Device bus type's ->runtime_suspend() callback has
492 *			completed successfully.  The device is regarded as
493 *			suspended.
494 *
495 * RPM_RESUMING		Device bus type's ->runtime_resume() callback is being
496 *			executed.
497 *
498 * RPM_SUSPENDING	Device bus type's ->runtime_suspend() callback is being
499 *			executed.
500 */
501
502enum rpm_status {
503	RPM_ACTIVE = 0,
504	RPM_RESUMING,
505	RPM_SUSPENDED,
506	RPM_SUSPENDING,
507};
508
509/*
510 * Device run-time power management request types.
511 *
512 * RPM_REQ_NONE		Do nothing.
513 *
514 * RPM_REQ_IDLE		Run the device bus type's ->runtime_idle() callback
515 *
516 * RPM_REQ_SUSPEND	Run the device bus type's ->runtime_suspend() callback
517 *
518 * RPM_REQ_AUTOSUSPEND	Same as RPM_REQ_SUSPEND, but not until the device has
519 *			been inactive for as long as power.autosuspend_delay
520 *
521 * RPM_REQ_RESUME	Run the device bus type's ->runtime_resume() callback
522 */
523
524enum rpm_request {
525	RPM_REQ_NONE = 0,
526	RPM_REQ_IDLE,
527	RPM_REQ_SUSPEND,
528	RPM_REQ_AUTOSUSPEND,
529	RPM_REQ_RESUME,
530};
531
532struct wakeup_source;
533struct wake_irq;
534struct pm_domain_data;
 
 
 
535
536struct pm_subsys_data {
537	spinlock_t lock;
538	unsigned int refcount;
539#ifdef CONFIG_PM_CLK
540	struct list_head clock_list;
541#endif
542#ifdef CONFIG_PM_GENERIC_DOMAINS
543	struct pm_domain_data *domain_data;
544#endif
545};
546
547/*
548 * Driver flags to control system suspend/resume behavior.
549 *
550 * These flags can be set by device drivers at the probe time.  They need not be
551 * cleared by the drivers as the driver core will take care of that.
552 *
553 * NO_DIRECT_COMPLETE: Do not apply direct-complete optimization to the device.
554 * SMART_PREPARE: Take the driver ->prepare callback return value into account.
555 * SMART_SUSPEND: Avoid resuming the device from runtime suspend.
556 * MAY_SKIP_RESUME: Allow driver "noirq" and "early" callbacks to be skipped.
557 *
558 * See Documentation/driver-api/pm/devices.rst for details.
559 */
560#define DPM_FLAG_NO_DIRECT_COMPLETE	BIT(0)
561#define DPM_FLAG_SMART_PREPARE		BIT(1)
562#define DPM_FLAG_SMART_SUSPEND		BIT(2)
563#define DPM_FLAG_MAY_SKIP_RESUME	BIT(3)
564
565struct dev_pm_info {
566	pm_message_t		power_state;
567	unsigned int		can_wakeup:1;
568	unsigned int		async_suspend:1;
569	bool			in_dpm_list:1;	/* Owned by the PM core */
570	bool			is_prepared:1;	/* Owned by the PM core */
571	bool			is_suspended:1;	/* Ditto */
572	bool			is_noirq_suspended:1;
573	bool			is_late_suspended:1;
574	bool			no_pm:1;
575	bool			early_init:1;	/* Owned by the PM core */
576	bool			direct_complete:1;	/* Owned by the PM core */
577	u32			driver_flags;
578	spinlock_t		lock;
579#ifdef CONFIG_PM_SLEEP
580	struct list_head	entry;
581	struct completion	completion;
582	struct wakeup_source	*wakeup;
583	bool			wakeup_path:1;
584	bool			syscore:1;
585	bool			no_pm_callbacks:1;	/* Owned by the PM core */
586	unsigned int		must_resume:1;	/* Owned by the PM core */
587	unsigned int		may_skip_resume:1;	/* Set by subsystems */
588#else
589	unsigned int		should_wakeup:1;
590#endif
591#ifdef CONFIG_PM
592	struct hrtimer		suspend_timer;
593	unsigned long		timer_expires;
594	struct work_struct	work;
595	wait_queue_head_t	wait_queue;
596	struct wake_irq		*wakeirq;
597	atomic_t		usage_count;
598	atomic_t		child_count;
599	unsigned int		disable_depth:3;
600	unsigned int		idle_notification:1;
601	unsigned int		request_pending:1;
602	unsigned int		deferred_resume:1;
 
603	unsigned int		runtime_auto:1;
604	bool			ignore_children:1;
605	unsigned int		no_callbacks:1;
606	unsigned int		irq_safe:1;
607	unsigned int		use_autosuspend:1;
608	unsigned int		timer_autosuspends:1;
609	unsigned int		memalloc_noio:1;
610	unsigned int		links_count;
611	enum rpm_request	request;
612	enum rpm_status		runtime_status;
613	int			runtime_error;
614	int			autosuspend_delay;
615	u64			last_busy;
616	u64			active_time;
617	u64			suspended_time;
618	u64			accounting_timestamp;
 
619#endif
620	struct pm_subsys_data	*subsys_data;  /* Owned by the subsystem. */
621	void (*set_latency_tolerance)(struct device *, s32);
622	struct dev_pm_qos	*qos;
623};
624
 
625extern int dev_pm_get_subsys_data(struct device *dev);
626extern void dev_pm_put_subsys_data(struct device *dev);
627
628/**
629 * struct dev_pm_domain - power management domain representation.
630 *
631 * @ops: Power management operations associated with this domain.
632 * @start: Called when a user needs to start the device via the domain.
633 * @detach: Called when removing a device from the domain.
634 * @activate: Called before executing probe routines for bus types and drivers.
635 * @sync: Called after successful driver probe.
636 * @dismiss: Called after unsuccessful driver probe and after driver removal.
637 *
638 * Power domains provide callbacks that are executed during system suspend,
639 * hibernation, system resume and during runtime PM transitions instead of
640 * subsystem-level and driver-level callbacks.
641 */
642struct dev_pm_domain {
643	struct dev_pm_ops	ops;
644	int (*start)(struct device *dev);
645	void (*detach)(struct device *dev, bool power_off);
646	int (*activate)(struct device *dev);
647	void (*sync)(struct device *dev);
648	void (*dismiss)(struct device *dev);
649};
650
651/*
652 * The PM_EVENT_ messages are also used by drivers implementing the legacy
653 * suspend framework, based on the ->suspend() and ->resume() callbacks common
654 * for suspend and hibernation transitions, according to the rules below.
655 */
656
657/* Necessary, because several drivers use PM_EVENT_PRETHAW */
658#define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
659
660/*
661 * One transition is triggered by resume(), after a suspend() call; the
662 * message is implicit:
663 *
664 * ON		Driver starts working again, responding to hardware events
665 *		and software requests.  The hardware may have gone through
666 *		a power-off reset, or it may have maintained state from the
667 *		previous suspend() which the driver will rely on while
668 *		resuming.  On most platforms, there are no restrictions on
669 *		availability of resources like clocks during resume().
670 *
671 * Other transitions are triggered by messages sent using suspend().  All
672 * these transitions quiesce the driver, so that I/O queues are inactive.
673 * That commonly entails turning off IRQs and DMA; there may be rules
674 * about how to quiesce that are specific to the bus or the device's type.
675 * (For example, network drivers mark the link state.)  Other details may
676 * differ according to the message:
677 *
678 * SUSPEND	Quiesce, enter a low power device state appropriate for
679 *		the upcoming system state (such as PCI_D3hot), and enable
680 *		wakeup events as appropriate.
681 *
682 * HIBERNATE	Enter a low power device state appropriate for the hibernation
683 *		state (eg. ACPI S4) and enable wakeup events as appropriate.
684 *
685 * FREEZE	Quiesce operations so that a consistent image can be saved;
686 *		but do NOT otherwise enter a low power device state, and do
687 *		NOT emit system wakeup events.
688 *
689 * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
690 *		the system from a snapshot taken after an earlier FREEZE.
691 *		Some drivers will need to reset their hardware state instead
692 *		of preserving it, to ensure that it's never mistaken for the
693 *		state which that earlier snapshot had set up.
694 *
695 * A minimally power-aware driver treats all messages as SUSPEND, fully
696 * reinitializes its device during resume() -- whether or not it was reset
697 * during the suspend/resume cycle -- and can't issue wakeup events.
698 *
699 * More power-aware drivers may also use low power states at runtime as
700 * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
701 * be able to use wakeup events to exit from runtime low-power states,
702 * or from system low-power states such as standby or suspend-to-RAM.
703 */
704
705#ifdef CONFIG_PM_SLEEP
706extern void device_pm_lock(void);
707extern void dpm_resume_start(pm_message_t state);
708extern void dpm_resume_end(pm_message_t state);
709extern void dpm_resume_noirq(pm_message_t state);
710extern void dpm_resume_early(pm_message_t state);
711extern void dpm_resume(pm_message_t state);
712extern void dpm_complete(pm_message_t state);
713
714extern void device_pm_unlock(void);
715extern int dpm_suspend_end(pm_message_t state);
716extern int dpm_suspend_start(pm_message_t state);
717extern int dpm_suspend_noirq(pm_message_t state);
718extern int dpm_suspend_late(pm_message_t state);
719extern int dpm_suspend(pm_message_t state);
720extern int dpm_prepare(pm_message_t state);
721
722extern void __suspend_report_result(const char *function, void *fn, int ret);
723
724#define suspend_report_result(fn, ret)					\
725	do {								\
726		__suspend_report_result(__func__, fn, ret);		\
727	} while (0)
728
729extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
730extern void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *));
731
732extern int pm_generic_prepare(struct device *dev);
733extern int pm_generic_suspend_late(struct device *dev);
734extern int pm_generic_suspend_noirq(struct device *dev);
735extern int pm_generic_suspend(struct device *dev);
736extern int pm_generic_resume_early(struct device *dev);
737extern int pm_generic_resume_noirq(struct device *dev);
738extern int pm_generic_resume(struct device *dev);
739extern int pm_generic_freeze_noirq(struct device *dev);
740extern int pm_generic_freeze_late(struct device *dev);
741extern int pm_generic_freeze(struct device *dev);
742extern int pm_generic_thaw_noirq(struct device *dev);
743extern int pm_generic_thaw_early(struct device *dev);
744extern int pm_generic_thaw(struct device *dev);
745extern int pm_generic_restore_noirq(struct device *dev);
746extern int pm_generic_restore_early(struct device *dev);
747extern int pm_generic_restore(struct device *dev);
748extern int pm_generic_poweroff_noirq(struct device *dev);
749extern int pm_generic_poweroff_late(struct device *dev);
750extern int pm_generic_poweroff(struct device *dev);
751extern void pm_generic_complete(struct device *dev);
752
753extern bool dev_pm_skip_resume(struct device *dev);
754extern bool dev_pm_skip_suspend(struct device *dev);
755
756#else /* !CONFIG_PM_SLEEP */
757
758#define device_pm_lock() do {} while (0)
759#define device_pm_unlock() do {} while (0)
760
761static inline int dpm_suspend_start(pm_message_t state)
762{
763	return 0;
764}
765
766#define suspend_report_result(fn, ret)		do {} while (0)
767
768static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
769{
770	return 0;
771}
772
773static inline void dpm_for_each_dev(void *data, void (*fn)(struct device *, void *))
774{
775}
776
777#define pm_generic_prepare		NULL
778#define pm_generic_suspend_late		NULL
779#define pm_generic_suspend_noirq	NULL
780#define pm_generic_suspend		NULL
781#define pm_generic_resume_early		NULL
782#define pm_generic_resume_noirq		NULL
783#define pm_generic_resume		NULL
784#define pm_generic_freeze_noirq		NULL
785#define pm_generic_freeze_late		NULL
786#define pm_generic_freeze		NULL
787#define pm_generic_thaw_noirq		NULL
788#define pm_generic_thaw_early		NULL
789#define pm_generic_thaw			NULL
790#define pm_generic_restore_noirq	NULL
791#define pm_generic_restore_early	NULL
792#define pm_generic_restore		NULL
793#define pm_generic_poweroff_noirq	NULL
794#define pm_generic_poweroff_late	NULL
795#define pm_generic_poweroff		NULL
796#define pm_generic_complete		NULL
797#endif /* !CONFIG_PM_SLEEP */
798
799/* How to reorder dpm_list after device_move() */
800enum dpm_order {
801	DPM_ORDER_NONE,
802	DPM_ORDER_DEV_AFTER_PARENT,
803	DPM_ORDER_PARENT_BEFORE_DEV,
804	DPM_ORDER_DEV_LAST,
805};
806
807#endif /* _LINUX_PM_H */
v3.5.6
 
  1/*
  2 *  pm.h - Power management interface
  3 *
  4 *  Copyright (C) 2000 Andrew Henroid
  5 *
  6 *  This program is free software; you can redistribute it and/or modify
  7 *  it under the terms of the GNU General Public License as published by
  8 *  the Free Software Foundation; either version 2 of the License, or
  9 *  (at your option) any later version.
 10 *
 11 *  This program is distributed in the hope that it will be useful,
 12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 *  GNU General Public License for more details.
 15 *
 16 *  You should have received a copy of the GNU General Public License
 17 *  along with this program; if not, write to the Free Software
 18 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 19 */
 20
 21#ifndef _LINUX_PM_H
 22#define _LINUX_PM_H
 23
 24#include <linux/list.h>
 25#include <linux/workqueue.h>
 26#include <linux/spinlock.h>
 27#include <linux/wait.h>
 28#include <linux/timer.h>
 
 29#include <linux/completion.h>
 30
 31/*
 32 * Callbacks for platform drivers to implement.
 33 */
 34extern void (*pm_idle)(void);
 35extern void (*pm_power_off)(void);
 36extern void (*pm_power_off_prepare)(void);
 37
 
 
 
 
 
 
 
 
 
 
 
 
 
 38/*
 39 * Device power management
 40 */
 41
 42struct device;
 43
 44#ifdef CONFIG_PM
 45extern const char power_group_name[];		/* = "power" */
 46#else
 47#define power_group_name	NULL
 48#endif
 49
 50typedef struct pm_message {
 51	int event;
 52} pm_message_t;
 53
 54/**
 55 * struct dev_pm_ops - device PM callbacks
 56 *
 57 * Several device power state transitions are externally visible, affecting
 58 * the state of pending I/O queues and (for drivers that touch hardware)
 59 * interrupts, wakeups, DMA, and other hardware state.  There may also be
 60 * internal transitions to various low-power modes which are transparent
 61 * to the rest of the driver stack (such as a driver that's ON gating off
 62 * clocks which are not in active use).
 63 *
 64 * The externally visible transitions are handled with the help of callbacks
 65 * included in this structure in such a way that two levels of callbacks are
 66 * involved.  First, the PM core executes callbacks provided by PM domains,
 67 * device types, classes and bus types.  They are the subsystem-level callbacks
 68 * supposed to execute callbacks provided by device drivers, although they may
 69 * choose not to do that.  If the driver callbacks are executed, they have to
 70 * collaborate with the subsystem-level callbacks to achieve the goals
 71 * appropriate for the given system transition, given transition phase and the
 72 * subsystem the device belongs to.
 73 *
 74 * @prepare: The principal role of this callback is to prevent new children of
 75 *	the device from being registered after it has returned (the driver's
 76 *	subsystem and generally the rest of the kernel is supposed to prevent
 77 *	new calls to the probe method from being made too once @prepare() has
 78 *	succeeded).  If @prepare() detects a situation it cannot handle (e.g.
 79 *	registration of a child already in progress), it may return -EAGAIN, so
 80 *	that the PM core can execute it once again (e.g. after a new child has
 81 *	been registered) to recover from the race condition.
 82 *	This method is executed for all kinds of suspend transitions and is
 83 *	followed by one of the suspend callbacks: @suspend(), @freeze(), or
 84 *	@poweroff().  The PM core executes subsystem-level @prepare() for all
 85 *	devices before starting to invoke suspend callbacks for any of them, so
 86 *	generally devices may be assumed to be functional or to respond to
 87 *	runtime resume requests while @prepare() is being executed.  However,
 88 *	device drivers may NOT assume anything about the availability of user
 89 *	space at that time and it is NOT valid to request firmware from within
 90 *	@prepare() (it's too late to do that).  It also is NOT valid to allocate
 
 
 
 
 
 
 
 
 
 
 91 *	substantial amounts of memory from @prepare() in the GFP_KERNEL mode.
 92 *	[To work around these limitations, drivers may register suspend and
 93 *	hibernation notifiers to be executed before the freezing of tasks.]
 94 *
 95 * @complete: Undo the changes made by @prepare().  This method is executed for
 96 *	all kinds of resume transitions, following one of the resume callbacks:
 97 *	@resume(), @thaw(), @restore().  Also called if the state transition
 98 *	fails before the driver's suspend callback: @suspend(), @freeze() or
 99 *	@poweroff(), can be executed (e.g. if the suspend callback fails for one
100 *	of the other devices that the PM core has unsuccessfully attempted to
101 *	suspend earlier).
102 *	The PM core executes subsystem-level @complete() after it has executed
103 *	the appropriate resume callbacks for all devices.
 
 
 
 
 
 
 
 
 
104 *
105 * @suspend: Executed before putting the system into a sleep state in which the
106 *	contents of main memory are preserved.  The exact action to perform
107 *	depends on the device's subsystem (PM domain, device type, class or bus
108 *	type), but generally the device must be quiescent after subsystem-level
109 *	@suspend() has returned, so that it doesn't do any I/O or DMA.
110 *	Subsystem-level @suspend() is executed for all devices after invoking
111 *	subsystem-level @prepare() for all of them.
112 *
113 * @suspend_late: Continue operations started by @suspend().  For a number of
114 *	devices @suspend_late() may point to the same callback routine as the
115 *	runtime suspend callback.
116 *
117 * @resume: Executed after waking the system up from a sleep state in which the
118 *	contents of main memory were preserved.  The exact action to perform
119 *	depends on the device's subsystem, but generally the driver is expected
120 *	to start working again, responding to hardware events and software
121 *	requests (the device itself may be left in a low-power state, waiting
122 *	for a runtime resume to occur).  The state of the device at the time its
123 *	driver's @resume() callback is run depends on the platform and subsystem
124 *	the device belongs to.  On most platforms, there are no restrictions on
125 *	availability of resources like clocks during @resume().
126 *	Subsystem-level @resume() is executed for all devices after invoking
127 *	subsystem-level @resume_noirq() for all of them.
128 *
129 * @resume_early: Prepare to execute @resume().  For a number of devices
130 *	@resume_early() may point to the same callback routine as the runtime
131 *	resume callback.
132 *
133 * @freeze: Hibernation-specific, executed before creating a hibernation image.
134 *	Analogous to @suspend(), but it should not enable the device to signal
135 *	wakeup events or change its power state.  The majority of subsystems
136 *	(with the notable exception of the PCI bus type) expect the driver-level
137 *	@freeze() to save the device settings in memory to be used by @restore()
138 *	during the subsequent resume from hibernation.
139 *	Subsystem-level @freeze() is executed for all devices after invoking
140 *	subsystem-level @prepare() for all of them.
141 *
142 * @freeze_late: Continue operations started by @freeze().  Analogous to
143 *	@suspend_late(), but it should not enable the device to signal wakeup
144 *	events or change its power state.
145 *
146 * @thaw: Hibernation-specific, executed after creating a hibernation image OR
147 *	if the creation of an image has failed.  Also executed after a failing
148 *	attempt to restore the contents of main memory from such an image.
149 *	Undo the changes made by the preceding @freeze(), so the device can be
150 *	operated in the same way as immediately before the call to @freeze().
151 *	Subsystem-level @thaw() is executed for all devices after invoking
152 *	subsystem-level @thaw_noirq() for all of them.  It also may be executed
153 *	directly after @freeze() in case of a transition error.
154 *
155 * @thaw_early: Prepare to execute @thaw().  Undo the changes made by the
156 *	preceding @freeze_late().
157 *
158 * @poweroff: Hibernation-specific, executed after saving a hibernation image.
159 *	Analogous to @suspend(), but it need not save the device's settings in
160 *	memory.
161 *	Subsystem-level @poweroff() is executed for all devices after invoking
162 *	subsystem-level @prepare() for all of them.
163 *
164 * @poweroff_late: Continue operations started by @poweroff().  Analogous to
165 *	@suspend_late(), but it need not save the device's settings in memory.
166 *
167 * @restore: Hibernation-specific, executed after restoring the contents of main
168 *	memory from a hibernation image, analogous to @resume().
169 *
170 * @restore_early: Prepare to execute @restore(), analogous to @resume_early().
171 *
172 * @suspend_noirq: Complete the actions started by @suspend().  Carry out any
173 *	additional operations required for suspending the device that might be
174 *	racing with its driver's interrupt handler, which is guaranteed not to
175 *	run while @suspend_noirq() is being executed.
176 *	It generally is expected that the device will be in a low-power state
177 *	(appropriate for the target system sleep state) after subsystem-level
178 *	@suspend_noirq() has returned successfully.  If the device can generate
179 *	system wakeup signals and is enabled to wake up the system, it should be
180 *	configured to do so at that time.  However, depending on the platform
181 *	and device's subsystem, @suspend() or @suspend_late() may be allowed to
182 *	put the device into the low-power state and configure it to generate
183 *	wakeup signals, in which case it generally is not necessary to define
184 *	@suspend_noirq().
185 *
186 * @resume_noirq: Prepare for the execution of @resume() by carrying out any
187 *	operations required for resuming the device that might be racing with
188 *	its driver's interrupt handler, which is guaranteed not to run while
189 *	@resume_noirq() is being executed.
190 *
191 * @freeze_noirq: Complete the actions started by @freeze().  Carry out any
192 *	additional operations required for freezing the device that might be
193 *	racing with its driver's interrupt handler, which is guaranteed not to
194 *	run while @freeze_noirq() is being executed.
195 *	The power state of the device should not be changed by either @freeze(),
196 *	or @freeze_late(), or @freeze_noirq() and it should not be configured to
197 *	signal system wakeup by any of these callbacks.
198 *
199 * @thaw_noirq: Prepare for the execution of @thaw() by carrying out any
200 *	operations required for thawing the device that might be racing with its
201 *	driver's interrupt handler, which is guaranteed not to run while
202 *	@thaw_noirq() is being executed.
203 *
204 * @poweroff_noirq: Complete the actions started by @poweroff().  Analogous to
205 *	@suspend_noirq(), but it need not save the device's settings in memory.
206 *
207 * @restore_noirq: Prepare for the execution of @restore() by carrying out any
208 *	operations required for thawing the device that might be racing with its
209 *	driver's interrupt handler, which is guaranteed not to run while
210 *	@restore_noirq() is being executed.  Analogous to @resume_noirq().
211 *
212 * All of the above callbacks, except for @complete(), return error codes.
213 * However, the error codes returned by the resume operations, @resume(),
214 * @thaw(), @restore(), @resume_noirq(), @thaw_noirq(), and @restore_noirq(), do
215 * not cause the PM core to abort the resume transition during which they are
216 * returned.  The error codes returned in those cases are only printed by the PM
217 * core to the system logs for debugging purposes.  Still, it is recommended
218 * that drivers only return error codes from their resume methods in case of an
219 * unrecoverable failure (i.e. when the device being handled refuses to resume
220 * and becomes unusable) to allow us to modify the PM core in the future, so
221 * that it can avoid attempting to handle devices that failed to resume and
222 * their children.
223 *
224 * It is allowed to unregister devices while the above callbacks are being
225 * executed.  However, a callback routine must NOT try to unregister the device
226 * it was called for, although it may unregister children of that device (for
227 * example, if it detects that a child was unplugged while the system was
228 * asleep).
229 *
230 * Refer to Documentation/power/devices.txt for more information about the role
231 * of the above callbacks in the system suspend process.
232 *
233 * There also are callbacks related to runtime power management of devices.
234 * Again, these callbacks are executed by the PM core only for subsystems
235 * (PM domains, device types, classes and bus types) and the subsystem-level
236 * callbacks are supposed to invoke the driver callbacks.  Moreover, the exact
237 * actions to be performed by a device driver's callbacks generally depend on
238 * the platform and subsystem the device belongs to.
239 *
240 * @runtime_suspend: Prepare the device for a condition in which it won't be
241 *	able to communicate with the CPU(s) and RAM due to power management.
242 *	This need not mean that the device should be put into a low-power state.
243 *	For example, if the device is behind a link which is about to be turned
244 *	off, the device may remain at full power.  If the device does go to low
245 *	power and is capable of generating runtime wakeup events, remote wakeup
246 *	(i.e., a hardware mechanism allowing the device to request a change of
247 *	its power state via an interrupt) should be enabled for it.
248 *
249 * @runtime_resume: Put the device into the fully active state in response to a
250 *	wakeup event generated by hardware or at the request of software.  If
251 *	necessary, put the device into the full-power state and restore its
252 *	registers, so that it is fully operational.
253 *
254 * @runtime_idle: Device appears to be inactive and it might be put into a
255 *	low-power state if all of the necessary conditions are satisfied.  Check
256 *	these conditions and handle the device as appropriate, possibly queueing
257 *	a suspend request for it.  The return value is ignored by the PM core.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
258 *
259 * Refer to Documentation/power/runtime_pm.txt for more information about the
260 * role of the above callbacks in device runtime power management.
 
 
 
 
261 *
 
 
 
262 */
263
264struct dev_pm_ops {
265	int (*prepare)(struct device *dev);
266	void (*complete)(struct device *dev);
267	int (*suspend)(struct device *dev);
268	int (*resume)(struct device *dev);
269	int (*freeze)(struct device *dev);
270	int (*thaw)(struct device *dev);
271	int (*poweroff)(struct device *dev);
272	int (*restore)(struct device *dev);
273	int (*suspend_late)(struct device *dev);
274	int (*resume_early)(struct device *dev);
275	int (*freeze_late)(struct device *dev);
276	int (*thaw_early)(struct device *dev);
277	int (*poweroff_late)(struct device *dev);
278	int (*restore_early)(struct device *dev);
279	int (*suspend_noirq)(struct device *dev);
280	int (*resume_noirq)(struct device *dev);
281	int (*freeze_noirq)(struct device *dev);
282	int (*thaw_noirq)(struct device *dev);
283	int (*poweroff_noirq)(struct device *dev);
284	int (*restore_noirq)(struct device *dev);
285	int (*runtime_suspend)(struct device *dev);
286	int (*runtime_resume)(struct device *dev);
287	int (*runtime_idle)(struct device *dev);
288};
289
290#ifdef CONFIG_PM_SLEEP
291#define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
292	.suspend = suspend_fn, \
293	.resume = resume_fn, \
294	.freeze = suspend_fn, \
295	.thaw = resume_fn, \
296	.poweroff = suspend_fn, \
297	.restore = resume_fn,
298#else
299#define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
300#endif
301
302#ifdef CONFIG_PM_RUNTIME
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
303#define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
304	.runtime_suspend = suspend_fn, \
305	.runtime_resume = resume_fn, \
306	.runtime_idle = idle_fn,
307#else
308#define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
309#endif
310
311/*
312 * Use this if you want to use the same suspend and resume callbacks for suspend
313 * to RAM and hibernation.
314 */
315#define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
316const struct dev_pm_ops name = { \
317	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
318}
319
320/*
321 * Use this for defining a set of PM operations to be used in all situations
322 * (sustem suspend, hibernation or runtime PM).
323 * NOTE: In general, system suspend callbacks, .suspend() and .resume(), should
324 * be different from the corresponding runtime PM callbacks, .runtime_suspend(),
325 * and .runtime_resume(), because .runtime_suspend() always works on an already
326 * quiescent device, while .suspend() should assume that the device may be doing
327 * something when it is called (it should ensure that the device will be
328 * quiescent after it has returned).  Therefore it's better to point the "late"
329 * suspend and "early" resume callback pointers, .suspend_late() and
330 * .resume_early(), to the same routines as .runtime_suspend() and
331 * .runtime_resume(), respectively (and analogously for hibernation).
332 */
333#define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
334const struct dev_pm_ops name = { \
335	SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
336	SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
337}
338
339/**
 
 
 
 
 
 
340 * PM_EVENT_ messages
341 *
342 * The following PM_EVENT_ messages are defined for the internal use of the PM
343 * core, in order to provide a mechanism allowing the high level suspend and
344 * hibernation code to convey the necessary information to the device PM core
345 * code:
346 *
347 * ON		No transition.
348 *
349 * FREEZE 	System is going to hibernate, call ->prepare() and ->freeze()
350 *		for all devices.
351 *
352 * SUSPEND	System is going to suspend, call ->prepare() and ->suspend()
353 *		for all devices.
354 *
355 * HIBERNATE	Hibernation image has been saved, call ->prepare() and
356 *		->poweroff() for all devices.
357 *
358 * QUIESCE	Contents of main memory are going to be restored from a (loaded)
359 *		hibernation image, call ->prepare() and ->freeze() for all
360 *		devices.
361 *
362 * RESUME	System is resuming, call ->resume() and ->complete() for all
363 *		devices.
364 *
365 * THAW		Hibernation image has been created, call ->thaw() and
366 *		->complete() for all devices.
367 *
368 * RESTORE	Contents of main memory have been restored from a hibernation
369 *		image, call ->restore() and ->complete() for all devices.
370 *
371 * RECOVER	Creation of a hibernation image or restoration of the main
372 *		memory contents from a hibernation image has failed, call
373 *		->thaw() and ->complete() for all devices.
374 *
375 * The following PM_EVENT_ messages are defined for internal use by
376 * kernel subsystems.  They are never issued by the PM core.
377 *
378 * USER_SUSPEND		Manual selective suspend was issued by userspace.
379 *
380 * USER_RESUME		Manual selective resume was issued by userspace.
381 *
382 * REMOTE_WAKEUP	Remote-wakeup request was received from the device.
383 *
384 * AUTO_SUSPEND		Automatic (device idle) runtime suspend was
385 *			initiated by the subsystem.
386 *
387 * AUTO_RESUME		Automatic (device needed) runtime resume was
388 *			requested by a driver.
389 */
390
391#define PM_EVENT_INVALID	(-1)
392#define PM_EVENT_ON		0x0000
393#define PM_EVENT_FREEZE 	0x0001
394#define PM_EVENT_SUSPEND	0x0002
395#define PM_EVENT_HIBERNATE	0x0004
396#define PM_EVENT_QUIESCE	0x0008
397#define PM_EVENT_RESUME		0x0010
398#define PM_EVENT_THAW		0x0020
399#define PM_EVENT_RESTORE	0x0040
400#define PM_EVENT_RECOVER	0x0080
401#define PM_EVENT_USER		0x0100
402#define PM_EVENT_REMOTE		0x0200
403#define PM_EVENT_AUTO		0x0400
404
405#define PM_EVENT_SLEEP		(PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
406#define PM_EVENT_USER_SUSPEND	(PM_EVENT_USER | PM_EVENT_SUSPEND)
407#define PM_EVENT_USER_RESUME	(PM_EVENT_USER | PM_EVENT_RESUME)
408#define PM_EVENT_REMOTE_RESUME	(PM_EVENT_REMOTE | PM_EVENT_RESUME)
409#define PM_EVENT_AUTO_SUSPEND	(PM_EVENT_AUTO | PM_EVENT_SUSPEND)
410#define PM_EVENT_AUTO_RESUME	(PM_EVENT_AUTO | PM_EVENT_RESUME)
411
412#define PMSG_INVALID	((struct pm_message){ .event = PM_EVENT_INVALID, })
413#define PMSG_ON		((struct pm_message){ .event = PM_EVENT_ON, })
414#define PMSG_FREEZE	((struct pm_message){ .event = PM_EVENT_FREEZE, })
415#define PMSG_QUIESCE	((struct pm_message){ .event = PM_EVENT_QUIESCE, })
416#define PMSG_SUSPEND	((struct pm_message){ .event = PM_EVENT_SUSPEND, })
417#define PMSG_HIBERNATE	((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
418#define PMSG_RESUME	((struct pm_message){ .event = PM_EVENT_RESUME, })
419#define PMSG_THAW	((struct pm_message){ .event = PM_EVENT_THAW, })
420#define PMSG_RESTORE	((struct pm_message){ .event = PM_EVENT_RESTORE, })
421#define PMSG_RECOVER	((struct pm_message){ .event = PM_EVENT_RECOVER, })
422#define PMSG_USER_SUSPEND	((struct pm_message) \
423					{ .event = PM_EVENT_USER_SUSPEND, })
424#define PMSG_USER_RESUME	((struct pm_message) \
425					{ .event = PM_EVENT_USER_RESUME, })
426#define PMSG_REMOTE_RESUME	((struct pm_message) \
427					{ .event = PM_EVENT_REMOTE_RESUME, })
428#define PMSG_AUTO_SUSPEND	((struct pm_message) \
429					{ .event = PM_EVENT_AUTO_SUSPEND, })
430#define PMSG_AUTO_RESUME	((struct pm_message) \
431					{ .event = PM_EVENT_AUTO_RESUME, })
432
433#define PMSG_IS_AUTO(msg)	(((msg).event & PM_EVENT_AUTO) != 0)
434
435/**
436 * Device run-time power management status.
437 *
438 * These status labels are used internally by the PM core to indicate the
439 * current status of a device with respect to the PM core operations.  They do
440 * not reflect the actual power state of the device or its status as seen by the
441 * driver.
442 *
443 * RPM_ACTIVE		Device is fully operational.  Indicates that the device
444 *			bus type's ->runtime_resume() callback has completed
445 *			successfully.
446 *
447 * RPM_SUSPENDED	Device bus type's ->runtime_suspend() callback has
448 *			completed successfully.  The device is regarded as
449 *			suspended.
450 *
451 * RPM_RESUMING		Device bus type's ->runtime_resume() callback is being
452 *			executed.
453 *
454 * RPM_SUSPENDING	Device bus type's ->runtime_suspend() callback is being
455 *			executed.
456 */
457
458enum rpm_status {
459	RPM_ACTIVE = 0,
460	RPM_RESUMING,
461	RPM_SUSPENDED,
462	RPM_SUSPENDING,
463};
464
465/**
466 * Device run-time power management request types.
467 *
468 * RPM_REQ_NONE		Do nothing.
469 *
470 * RPM_REQ_IDLE		Run the device bus type's ->runtime_idle() callback
471 *
472 * RPM_REQ_SUSPEND	Run the device bus type's ->runtime_suspend() callback
473 *
474 * RPM_REQ_AUTOSUSPEND	Same as RPM_REQ_SUSPEND, but not until the device has
475 *			been inactive for as long as power.autosuspend_delay
476 *
477 * RPM_REQ_RESUME	Run the device bus type's ->runtime_resume() callback
478 */
479
480enum rpm_request {
481	RPM_REQ_NONE = 0,
482	RPM_REQ_IDLE,
483	RPM_REQ_SUSPEND,
484	RPM_REQ_AUTOSUSPEND,
485	RPM_REQ_RESUME,
486};
487
488struct wakeup_source;
489
490struct pm_domain_data {
491	struct list_head list_node;
492	struct device *dev;
493};
494
495struct pm_subsys_data {
496	spinlock_t lock;
497	unsigned int refcount;
498#ifdef CONFIG_PM_CLK
499	struct list_head clock_list;
500#endif
501#ifdef CONFIG_PM_GENERIC_DOMAINS
502	struct pm_domain_data *domain_data;
503#endif
504};
505
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
506struct dev_pm_info {
507	pm_message_t		power_state;
508	unsigned int		can_wakeup:1;
509	unsigned int		async_suspend:1;
 
510	bool			is_prepared:1;	/* Owned by the PM core */
511	bool			is_suspended:1;	/* Ditto */
512	bool			ignore_children:1;
 
 
 
 
 
513	spinlock_t		lock;
514#ifdef CONFIG_PM_SLEEP
515	struct list_head	entry;
516	struct completion	completion;
517	struct wakeup_source	*wakeup;
518	bool			wakeup_path:1;
 
 
 
 
519#else
520	unsigned int		should_wakeup:1;
521#endif
522#ifdef CONFIG_PM_RUNTIME
523	struct timer_list	suspend_timer;
524	unsigned long		timer_expires;
525	struct work_struct	work;
526	wait_queue_head_t	wait_queue;
 
527	atomic_t		usage_count;
528	atomic_t		child_count;
529	unsigned int		disable_depth:3;
530	unsigned int		idle_notification:1;
531	unsigned int		request_pending:1;
532	unsigned int		deferred_resume:1;
533	unsigned int		run_wake:1;
534	unsigned int		runtime_auto:1;
 
535	unsigned int		no_callbacks:1;
536	unsigned int		irq_safe:1;
537	unsigned int		use_autosuspend:1;
538	unsigned int		timer_autosuspends:1;
 
 
539	enum rpm_request	request;
540	enum rpm_status		runtime_status;
541	int			runtime_error;
542	int			autosuspend_delay;
543	unsigned long		last_busy;
544	unsigned long		active_jiffies;
545	unsigned long		suspended_jiffies;
546	unsigned long		accounting_timestamp;
547	struct dev_pm_qos_request *pq_req;
548#endif
549	struct pm_subsys_data	*subsys_data;  /* Owned by the subsystem. */
550	struct pm_qos_constraints *constraints;
 
551};
552
553extern void update_pm_runtime_accounting(struct device *dev);
554extern int dev_pm_get_subsys_data(struct device *dev);
555extern int dev_pm_put_subsys_data(struct device *dev);
556
557/*
 
 
 
 
 
 
 
 
 
558 * Power domains provide callbacks that are executed during system suspend,
559 * hibernation, system resume and during runtime PM transitions along with
560 * subsystem-level and driver-level callbacks.
561 */
562struct dev_pm_domain {
563	struct dev_pm_ops	ops;
 
 
 
 
 
564};
565
566/*
567 * The PM_EVENT_ messages are also used by drivers implementing the legacy
568 * suspend framework, based on the ->suspend() and ->resume() callbacks common
569 * for suspend and hibernation transitions, according to the rules below.
570 */
571
572/* Necessary, because several drivers use PM_EVENT_PRETHAW */
573#define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
574
575/*
576 * One transition is triggered by resume(), after a suspend() call; the
577 * message is implicit:
578 *
579 * ON		Driver starts working again, responding to hardware events
580 * 		and software requests.  The hardware may have gone through
581 * 		a power-off reset, or it may have maintained state from the
582 * 		previous suspend() which the driver will rely on while
583 * 		resuming.  On most platforms, there are no restrictions on
584 * 		availability of resources like clocks during resume().
585 *
586 * Other transitions are triggered by messages sent using suspend().  All
587 * these transitions quiesce the driver, so that I/O queues are inactive.
588 * That commonly entails turning off IRQs and DMA; there may be rules
589 * about how to quiesce that are specific to the bus or the device's type.
590 * (For example, network drivers mark the link state.)  Other details may
591 * differ according to the message:
592 *
593 * SUSPEND	Quiesce, enter a low power device state appropriate for
594 * 		the upcoming system state (such as PCI_D3hot), and enable
595 * 		wakeup events as appropriate.
596 *
597 * HIBERNATE	Enter a low power device state appropriate for the hibernation
598 * 		state (eg. ACPI S4) and enable wakeup events as appropriate.
599 *
600 * FREEZE	Quiesce operations so that a consistent image can be saved;
601 * 		but do NOT otherwise enter a low power device state, and do
602 * 		NOT emit system wakeup events.
603 *
604 * PRETHAW	Quiesce as if for FREEZE; additionally, prepare for restoring
605 * 		the system from a snapshot taken after an earlier FREEZE.
606 * 		Some drivers will need to reset their hardware state instead
607 * 		of preserving it, to ensure that it's never mistaken for the
608 * 		state which that earlier snapshot had set up.
609 *
610 * A minimally power-aware driver treats all messages as SUSPEND, fully
611 * reinitializes its device during resume() -- whether or not it was reset
612 * during the suspend/resume cycle -- and can't issue wakeup events.
613 *
614 * More power-aware drivers may also use low power states at runtime as
615 * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
616 * be able to use wakeup events to exit from runtime low-power states,
617 * or from system low-power states such as standby or suspend-to-RAM.
618 */
619
620#ifdef CONFIG_PM_SLEEP
621extern void device_pm_lock(void);
622extern void dpm_resume_start(pm_message_t state);
623extern void dpm_resume_end(pm_message_t state);
 
 
624extern void dpm_resume(pm_message_t state);
625extern void dpm_complete(pm_message_t state);
626
627extern void device_pm_unlock(void);
628extern int dpm_suspend_end(pm_message_t state);
629extern int dpm_suspend_start(pm_message_t state);
 
 
630extern int dpm_suspend(pm_message_t state);
631extern int dpm_prepare(pm_message_t state);
632
633extern void __suspend_report_result(const char *function, void *fn, int ret);
634
635#define suspend_report_result(fn, ret)					\
636	do {								\
637		__suspend_report_result(__func__, fn, ret);		\
638	} while (0)
639
640extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
 
641
642extern int pm_generic_prepare(struct device *dev);
643extern int pm_generic_suspend_late(struct device *dev);
644extern int pm_generic_suspend_noirq(struct device *dev);
645extern int pm_generic_suspend(struct device *dev);
646extern int pm_generic_resume_early(struct device *dev);
647extern int pm_generic_resume_noirq(struct device *dev);
648extern int pm_generic_resume(struct device *dev);
649extern int pm_generic_freeze_noirq(struct device *dev);
650extern int pm_generic_freeze_late(struct device *dev);
651extern int pm_generic_freeze(struct device *dev);
652extern int pm_generic_thaw_noirq(struct device *dev);
653extern int pm_generic_thaw_early(struct device *dev);
654extern int pm_generic_thaw(struct device *dev);
655extern int pm_generic_restore_noirq(struct device *dev);
656extern int pm_generic_restore_early(struct device *dev);
657extern int pm_generic_restore(struct device *dev);
658extern int pm_generic_poweroff_noirq(struct device *dev);
659extern int pm_generic_poweroff_late(struct device *dev);
660extern int pm_generic_poweroff(struct device *dev);
661extern void pm_generic_complete(struct device *dev);
662
 
 
 
663#else /* !CONFIG_PM_SLEEP */
664
665#define device_pm_lock() do {} while (0)
666#define device_pm_unlock() do {} while (0)
667
668static inline int dpm_suspend_start(pm_message_t state)
669{
670	return 0;
671}
672
673#define suspend_report_result(fn, ret)		do {} while (0)
674
675static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
676{
677	return 0;
678}
679
680#define pm_generic_prepare	NULL
681#define pm_generic_suspend	NULL
682#define pm_generic_resume	NULL
683#define pm_generic_freeze	NULL
684#define pm_generic_thaw		NULL
685#define pm_generic_restore	NULL
686#define pm_generic_poweroff	NULL
687#define pm_generic_complete	NULL
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
688#endif /* !CONFIG_PM_SLEEP */
689
690/* How to reorder dpm_list after device_move() */
691enum dpm_order {
692	DPM_ORDER_NONE,
693	DPM_ORDER_DEV_AFTER_PARENT,
694	DPM_ORDER_PARENT_BEFORE_DEV,
695	DPM_ORDER_DEV_LAST,
696};
697
698#endif /* _LINUX_PM_H */