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