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