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