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TOMOYO Linux Cross Reference
Linux/include/linux/pm.h

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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_idle)(void);
 35 extern void (*pm_power_off)(void);
 36 extern void (*pm_power_off_prepare)(void);
 37 
 38 /*
 39  * Device power management
 40  */
 41 
 42 struct device;
 43 
 44 #ifdef CONFIG_PM
 45 extern const char power_group_name[];           /* = "power" */
 46 #else
 47 #define power_group_name        NULL
 48 #endif
 49 
 50 typedef struct pm_message {
 51         int event;
 52 } pm_message_t;
 53 
 54 /**
 55  * struct dev_pm_ops - device PM callbacks
 56  *
 57  * Several driver power state transitions are externally visible, affecting
 58  * the state of pending I/O queues and (for drivers that touch hardware)
 59  * interrupts, wakeups, DMA, and other hardware state.  There may also be
 60  * internal transitions to various low power modes, which are transparent
 61  * to the rest of the driver stack (such as a driver that's ON gating off
 62  * clocks which are not in active use).
 63  *
 64  * The externally visible transitions are handled with the help of the following
 65  * callbacks included in this structure:
 66  *
 67  * @prepare: Prepare the device for the upcoming transition, but do NOT change
 68  *      its hardware state.  Prevent new children of the device from being
 69  *      registered after @prepare() returns (the driver's subsystem and
 70  *      generally the rest of the kernel is supposed to prevent new calls to the
 71  *      probe method from being made too once @prepare() has succeeded).  If
 72  *      @prepare() detects a situation it cannot handle (e.g. registration of a
 73  *      child already in progress), it may return -EAGAIN, so that the PM core
 74  *      can execute it once again (e.g. after the new child has been registered)
 75  *      to recover from the race condition.  This method is executed for all
 76  *      kinds of suspend transitions and is followed by one of the suspend
 77  *      callbacks: @suspend(), @freeze(), or @poweroff().
 78  *      The PM core executes @prepare() for all devices before starting to
 79  *      execute suspend callbacks for any of them, so drivers may assume all of
 80  *      the other devices to be present and functional while @prepare() is being
 81  *      executed.  In particular, it is safe to make GFP_KERNEL memory
 82  *      allocations from within @prepare().  However, drivers may NOT assume
 83  *      anything about the availability of the user space at that time and it
 84  *      is not correct to request firmware from within @prepare() (it's too
 85  *      late to do that).  [To work around this limitation, drivers may
 86  *      register suspend and hibernation notifiers that are executed before the
 87  *      freezing of tasks.]
 88  *
 89  * @complete: Undo the changes made by @prepare().  This method is executed for
 90  *      all kinds of resume transitions, following one of the resume callbacks:
 91  *      @resume(), @thaw(), @restore().  Also called if the state transition
 92  *      fails before the driver's suspend callback (@suspend(), @freeze(),
 93  *      @poweroff()) can be executed (e.g. if the suspend callback fails for one
 94  *      of the other devices that the PM core has unsuccessfully attempted to
 95  *      suspend earlier).
 96  *      The PM core executes @complete() after it has executed the appropriate
 97  *      resume callback for all devices.
 98  *
 99  * @suspend: Executed before putting the system into a sleep state in which the
100  *      contents of main memory are preserved.  Quiesce the device, put it into
101  *      a low power state appropriate for the upcoming system state (such as
102  *      PCI_D3hot), and enable wakeup events as appropriate.
103  *
104  * @resume: Executed after waking the system up from a sleep state in which the
105  *      contents of main memory were preserved.  Put the device into the
106  *      appropriate state, according to the information saved in memory by the
107  *      preceding @suspend().  The driver starts working again, responding to
108  *      hardware events and software requests.  The hardware may have gone
109  *      through a power-off reset, or it may have maintained state from the
110  *      previous suspend() which the driver may rely on while resuming.  On most
111  *      platforms, there are no restrictions on availability of resources like
112  *      clocks during @resume().
113  *
114  * @freeze: Hibernation-specific, executed before creating a hibernation image.
115  *      Quiesce operations so that a consistent image can be created, but do NOT
116  *      otherwise put the device into a low power device state and do NOT emit
117  *      system wakeup events.  Save in main memory the device settings to be
118  *      used by @restore() during the subsequent resume from hibernation or by
119  *      the subsequent @thaw(), if the creation of the image or the restoration
120  *      of main memory contents from it fails.
121  *
122  * @thaw: Hibernation-specific, executed after creating a hibernation image OR
123  *      if the creation of the image fails.  Also executed after a failing
124  *      attempt to restore the contents of main memory from such an image.
125  *      Undo the changes made by the preceding @freeze(), so the device can be
126  *      operated in the same way as immediately before the call to @freeze().
127  *
128  * @poweroff: Hibernation-specific, executed after saving a hibernation image.
129  *      Quiesce the device, put it into a low power state appropriate for the
130  *      upcoming system state (such as PCI_D3hot), and enable wakeup events as
131  *      appropriate.
132  *
133  * @restore: Hibernation-specific, executed after restoring the contents of main
134  *      memory from a hibernation image.  Driver starts working again,
135  *      responding to hardware events and software requests.  Drivers may NOT
136  *      make ANY assumptions about the hardware state right prior to @restore().
137  *      On most platforms, there are no restrictions on availability of
138  *      resources like clocks during @restore().
139  *
140  * @suspend_noirq: Complete the operations of ->suspend() by carrying out any
141  *      actions required for suspending the device that need interrupts to be
142  *      disabled
143  *
144  * @resume_noirq: Prepare for the execution of ->resume() by carrying out any
145  *      actions required for resuming the device that need interrupts to be
146  *      disabled
147  *
148  * @freeze_noirq: Complete the operations of ->freeze() by carrying out any
149  *      actions required for freezing the device that need interrupts to be
150  *      disabled
151  *
152  * @thaw_noirq: Prepare for the execution of ->thaw() by carrying out any
153  *      actions required for thawing the device that need interrupts to be
154  *      disabled
155  *
156  * @poweroff_noirq: Complete the operations of ->poweroff() by carrying out any
157  *      actions required for handling the device that need interrupts to be
158  *      disabled
159  *
160  * @restore_noirq: Prepare for the execution of ->restore() by carrying out any
161  *      actions required for restoring the operations of the device that need
162  *      interrupts to be disabled
163  *
164  * All of the above callbacks, except for @complete(), return error codes.
165  * However, the error codes returned by the resume operations, @resume(),
166  * @thaw(), @restore(), @resume_noirq(), @thaw_noirq(), and @restore_noirq() do
167  * not cause the PM core to abort the resume transition during which they are
168  * returned.  The error codes returned in that cases are only printed by the PM
169  * core to the system logs for debugging purposes.  Still, it is recommended
170  * that drivers only return error codes from their resume methods in case of an
171  * unrecoverable failure (i.e. when the device being handled refuses to resume
172  * and becomes unusable) to allow us to modify the PM core in the future, so
173  * that it can avoid attempting to handle devices that failed to resume and
174  * their children.
175  *
176  * It is allowed to unregister devices while the above callbacks are being
177  * executed.  However, it is not allowed to unregister a device from within any
178  * of its own callbacks.
179  *
180  * There also are the following callbacks related to run-time power management
181  * of devices:
182  *
183  * @runtime_suspend: Prepare the device for a condition in which it won't be
184  *      able to communicate with the CPU(s) and RAM due to power management.
185  *      This need not mean that the device should be put into a low power state.
186  *      For example, if the device is behind a link which is about to be turned
187  *      off, the device may remain at full power.  If the device does go to low
188  *      power and is capable of generating run-time wake-up events, remote
189  *      wake-up (i.e., a hardware mechanism allowing the device to request a
190  *      change of its power state via a wake-up event, such as PCI PME) should
191  *      be enabled for it.
192  *
193  * @runtime_resume: Put the device into the fully active state in response to a
194  *      wake-up event generated by hardware or at the request of software.  If
195  *      necessary, put the device into the full power state and restore its
196  *      registers, so that it is fully operational.
197  *
198  * @runtime_idle: Device appears to be inactive and it might be put into a low
199  *      power state if all of the necessary conditions are satisfied.  Check
200  *      these conditions and handle the device as appropriate, possibly queueing
201  *      a suspend request for it.  The return value is ignored by the PM core.
202  */
203 
204 struct dev_pm_ops {
205         int (*prepare)(struct device *dev);
206         void (*complete)(struct device *dev);
207         int (*suspend)(struct device *dev);
208         int (*resume)(struct device *dev);
209         int (*freeze)(struct device *dev);
210         int (*thaw)(struct device *dev);
211         int (*poweroff)(struct device *dev);
212         int (*restore)(struct device *dev);
213         int (*suspend_noirq)(struct device *dev);
214         int (*resume_noirq)(struct device *dev);
215         int (*freeze_noirq)(struct device *dev);
216         int (*thaw_noirq)(struct device *dev);
217         int (*poweroff_noirq)(struct device *dev);
218         int (*restore_noirq)(struct device *dev);
219         int (*runtime_suspend)(struct device *dev);
220         int (*runtime_resume)(struct device *dev);
221         int (*runtime_idle)(struct device *dev);
222 };
223 
224 #ifdef CONFIG_PM_SLEEP
225 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
226         .suspend = suspend_fn, \
227         .resume = resume_fn, \
228         .freeze = suspend_fn, \
229         .thaw = resume_fn, \
230         .poweroff = suspend_fn, \
231         .restore = resume_fn,
232 #else
233 #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn)
234 #endif
235 
236 #ifdef CONFIG_PM_RUNTIME
237 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
238         .runtime_suspend = suspend_fn, \
239         .runtime_resume = resume_fn, \
240         .runtime_idle = idle_fn,
241 #else
242 #define SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn)
243 #endif
244 
245 /*
246  * Use this if you want to use the same suspend and resume callbacks for suspend
247  * to RAM and hibernation.
248  */
249 #define SIMPLE_DEV_PM_OPS(name, suspend_fn, resume_fn) \
250 const struct dev_pm_ops name = { \
251         SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
252 }
253 
254 /*
255  * Use this for defining a set of PM operations to be used in all situations
256  * (sustem suspend, hibernation or runtime PM).
257  */
258 #define UNIVERSAL_DEV_PM_OPS(name, suspend_fn, resume_fn, idle_fn) \
259 const struct dev_pm_ops name = { \
260         SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \
261         SET_RUNTIME_PM_OPS(suspend_fn, resume_fn, idle_fn) \
262 }
263 
264 /*
265  * Use this for subsystems (bus types, device types, device classes) that don't
266  * need any special suspend/resume handling in addition to invoking the PM
267  * callbacks provided by device drivers supporting both the system sleep PM and
268  * runtime PM, make the pm member point to generic_subsys_pm_ops.
269  */
270 #ifdef CONFIG_PM
271 extern struct dev_pm_ops generic_subsys_pm_ops;
272 #define GENERIC_SUBSYS_PM_OPS   (&generic_subsys_pm_ops)
273 #else
274 #define GENERIC_SUBSYS_PM_OPS   NULL
275 #endif
276 
277 /**
278  * PM_EVENT_ messages
279  *
280  * The following PM_EVENT_ messages are defined for the internal use of the PM
281  * core, in order to provide a mechanism allowing the high level suspend and
282  * hibernation code to convey the necessary information to the device PM core
283  * code:
284  *
285  * ON           No transition.
286  *
287  * FREEZE       System is going to hibernate, call ->prepare() and ->freeze()
288  *              for all devices.
289  *
290  * SUSPEND      System is going to suspend, call ->prepare() and ->suspend()
291  *              for all devices.
292  *
293  * HIBERNATE    Hibernation image has been saved, call ->prepare() and
294  *              ->poweroff() for all devices.
295  *
296  * QUIESCE      Contents of main memory are going to be restored from a (loaded)
297  *              hibernation image, call ->prepare() and ->freeze() for all
298  *              devices.
299  *
300  * RESUME       System is resuming, call ->resume() and ->complete() for all
301  *              devices.
302  *
303  * THAW         Hibernation image has been created, call ->thaw() and
304  *              ->complete() for all devices.
305  *
306  * RESTORE      Contents of main memory have been restored from a hibernation
307  *              image, call ->restore() and ->complete() for all devices.
308  *
309  * RECOVER      Creation of a hibernation image or restoration of the main
310  *              memory contents from a hibernation image has failed, call
311  *              ->thaw() and ->complete() for all devices.
312  *
313  * The following PM_EVENT_ messages are defined for internal use by
314  * kernel subsystems.  They are never issued by the PM core.
315  *
316  * USER_SUSPEND         Manual selective suspend was issued by userspace.
317  *
318  * USER_RESUME          Manual selective resume was issued by userspace.
319  *
320  * REMOTE_WAKEUP        Remote-wakeup request was received from the device.
321  *
322  * AUTO_SUSPEND         Automatic (device idle) runtime suspend was
323  *                      initiated by the subsystem.
324  *
325  * AUTO_RESUME          Automatic (device needed) runtime resume was
326  *                      requested by a driver.
327  */
328 
329 #define PM_EVENT_ON             0x0000
330 #define PM_EVENT_FREEZE         0x0001
331 #define PM_EVENT_SUSPEND        0x0002
332 #define PM_EVENT_HIBERNATE      0x0004
333 #define PM_EVENT_QUIESCE        0x0008
334 #define PM_EVENT_RESUME         0x0010
335 #define PM_EVENT_THAW           0x0020
336 #define PM_EVENT_RESTORE        0x0040
337 #define PM_EVENT_RECOVER        0x0080
338 #define PM_EVENT_USER           0x0100
339 #define PM_EVENT_REMOTE         0x0200
340 #define PM_EVENT_AUTO           0x0400
341 
342 #define PM_EVENT_SLEEP          (PM_EVENT_SUSPEND | PM_EVENT_HIBERNATE)
343 #define PM_EVENT_USER_SUSPEND   (PM_EVENT_USER | PM_EVENT_SUSPEND)
344 #define PM_EVENT_USER_RESUME    (PM_EVENT_USER | PM_EVENT_RESUME)
345 #define PM_EVENT_REMOTE_RESUME  (PM_EVENT_REMOTE | PM_EVENT_RESUME)
346 #define PM_EVENT_AUTO_SUSPEND   (PM_EVENT_AUTO | PM_EVENT_SUSPEND)
347 #define PM_EVENT_AUTO_RESUME    (PM_EVENT_AUTO | PM_EVENT_RESUME)
348 
349 #define PMSG_ON         ((struct pm_message){ .event = PM_EVENT_ON, })
350 #define PMSG_FREEZE     ((struct pm_message){ .event = PM_EVENT_FREEZE, })
351 #define PMSG_QUIESCE    ((struct pm_message){ .event = PM_EVENT_QUIESCE, })
352 #define PMSG_SUSPEND    ((struct pm_message){ .event = PM_EVENT_SUSPEND, })
353 #define PMSG_HIBERNATE  ((struct pm_message){ .event = PM_EVENT_HIBERNATE, })
354 #define PMSG_RESUME     ((struct pm_message){ .event = PM_EVENT_RESUME, })
355 #define PMSG_THAW       ((struct pm_message){ .event = PM_EVENT_THAW, })
356 #define PMSG_RESTORE    ((struct pm_message){ .event = PM_EVENT_RESTORE, })
357 #define PMSG_RECOVER    ((struct pm_message){ .event = PM_EVENT_RECOVER, })
358 #define PMSG_USER_SUSPEND       ((struct pm_message) \
359                                         { .event = PM_EVENT_USER_SUSPEND, })
360 #define PMSG_USER_RESUME        ((struct pm_message) \
361                                         { .event = PM_EVENT_USER_RESUME, })
362 #define PMSG_REMOTE_RESUME      ((struct pm_message) \
363                                         { .event = PM_EVENT_REMOTE_RESUME, })
364 #define PMSG_AUTO_SUSPEND       ((struct pm_message) \
365                                         { .event = PM_EVENT_AUTO_SUSPEND, })
366 #define PMSG_AUTO_RESUME        ((struct pm_message) \
367                                         { .event = PM_EVENT_AUTO_RESUME, })
368 
369 /**
370  * Device run-time power management status.
371  *
372  * These status labels are used internally by the PM core to indicate the
373  * current status of a device with respect to the PM core operations.  They do
374  * not reflect the actual power state of the device or its status as seen by the
375  * driver.
376  *
377  * RPM_ACTIVE           Device is fully operational.  Indicates that the device
378  *                      bus type's ->runtime_resume() callback has completed
379  *                      successfully.
380  *
381  * RPM_SUSPENDED        Device bus type's ->runtime_suspend() callback has
382  *                      completed successfully.  The device is regarded as
383  *                      suspended.
384  *
385  * RPM_RESUMING         Device bus type's ->runtime_resume() callback is being
386  *                      executed.
387  *
388  * RPM_SUSPENDING       Device bus type's ->runtime_suspend() callback is being
389  *                      executed.
390  */
391 
392 enum rpm_status {
393         RPM_ACTIVE = 0,
394         RPM_RESUMING,
395         RPM_SUSPENDED,
396         RPM_SUSPENDING,
397 };
398 
399 /**
400  * Device run-time power management request types.
401  *
402  * RPM_REQ_NONE         Do nothing.
403  *
404  * RPM_REQ_IDLE         Run the device bus type's ->runtime_idle() callback
405  *
406  * RPM_REQ_SUSPEND      Run the device bus type's ->runtime_suspend() callback
407  *
408  * RPM_REQ_AUTOSUSPEND  Same as RPM_REQ_SUSPEND, but not until the device has
409  *                      been inactive for as long as power.autosuspend_delay
410  *
411  * RPM_REQ_RESUME       Run the device bus type's ->runtime_resume() callback
412  */
413 
414 enum rpm_request {
415         RPM_REQ_NONE = 0,
416         RPM_REQ_IDLE,
417         RPM_REQ_SUSPEND,
418         RPM_REQ_AUTOSUSPEND,
419         RPM_REQ_RESUME,
420 };
421 
422 struct wakeup_source;
423 
424 struct dev_pm_info {
425         pm_message_t            power_state;
426         unsigned int            can_wakeup:1;
427         unsigned int            async_suspend:1;
428         bool                    is_prepared:1;  /* Owned by the PM core */
429         bool                    is_suspended:1; /* Ditto */
430         spinlock_t              lock;
431 #ifdef CONFIG_PM_SLEEP
432         struct list_head        entry;
433         struct completion       completion;
434         struct wakeup_source    *wakeup;
435 #else
436         unsigned int            should_wakeup:1;
437 #endif
438 #ifdef CONFIG_PM_RUNTIME
439         struct timer_list       suspend_timer;
440         unsigned long           timer_expires;
441         struct work_struct      work;
442         wait_queue_head_t       wait_queue;
443         atomic_t                usage_count;
444         atomic_t                child_count;
445         unsigned int            disable_depth:3;
446         unsigned int            ignore_children:1;
447         unsigned int            idle_notification:1;
448         unsigned int            request_pending:1;
449         unsigned int            deferred_resume:1;
450         unsigned int            run_wake:1;
451         unsigned int            runtime_auto:1;
452         unsigned int            no_callbacks:1;
453         unsigned int            irq_safe:1;
454         unsigned int            use_autosuspend:1;
455         unsigned int            timer_autosuspends:1;
456         enum rpm_request        request;
457         enum rpm_status         runtime_status;
458         int                     runtime_error;
459         int                     autosuspend_delay;
460         unsigned long           last_busy;
461         unsigned long           active_jiffies;
462         unsigned long           suspended_jiffies;
463         unsigned long           accounting_timestamp;
464 #endif
465 };
466 
467 extern void update_pm_runtime_accounting(struct device *dev);
468 
469 /*
470  * Power domains provide callbacks that are executed during system suspend,
471  * hibernation, system resume and during runtime PM transitions along with
472  * subsystem-level and driver-level callbacks.
473  */
474 struct dev_power_domain {
475         struct dev_pm_ops       ops;
476 };
477 
478 /*
479  * The PM_EVENT_ messages are also used by drivers implementing the legacy
480  * suspend framework, based on the ->suspend() and ->resume() callbacks common
481  * for suspend and hibernation transitions, according to the rules below.
482  */
483 
484 /* Necessary, because several drivers use PM_EVENT_PRETHAW */
485 #define PM_EVENT_PRETHAW PM_EVENT_QUIESCE
486 
487 /*
488  * One transition is triggered by resume(), after a suspend() call; the
489  * message is implicit:
490  *
491  * ON           Driver starts working again, responding to hardware events
492  *              and software requests.  The hardware may have gone through
493  *              a power-off reset, or it may have maintained state from the
494  *              previous suspend() which the driver will rely on while
495  *              resuming.  On most platforms, there are no restrictions on
496  *              availability of resources like clocks during resume().
497  *
498  * Other transitions are triggered by messages sent using suspend().  All
499  * these transitions quiesce the driver, so that I/O queues are inactive.
500  * That commonly entails turning off IRQs and DMA; there may be rules
501  * about how to quiesce that are specific to the bus or the device's type.
502  * (For example, network drivers mark the link state.)  Other details may
503  * differ according to the message:
504  *
505  * SUSPEND      Quiesce, enter a low power device state appropriate for
506  *              the upcoming system state (such as PCI_D3hot), and enable
507  *              wakeup events as appropriate.
508  *
509  * HIBERNATE    Enter a low power device state appropriate for the hibernation
510  *              state (eg. ACPI S4) and enable wakeup events as appropriate.
511  *
512  * FREEZE       Quiesce operations so that a consistent image can be saved;
513  *              but do NOT otherwise enter a low power device state, and do
514  *              NOT emit system wakeup events.
515  *
516  * PRETHAW      Quiesce as if for FREEZE; additionally, prepare for restoring
517  *              the system from a snapshot taken after an earlier FREEZE.
518  *              Some drivers will need to reset their hardware state instead
519  *              of preserving it, to ensure that it's never mistaken for the
520  *              state which that earlier snapshot had set up.
521  *
522  * A minimally power-aware driver treats all messages as SUSPEND, fully
523  * reinitializes its device during resume() -- whether or not it was reset
524  * during the suspend/resume cycle -- and can't issue wakeup events.
525  *
526  * More power-aware drivers may also use low power states at runtime as
527  * well as during system sleep states like PM_SUSPEND_STANDBY.  They may
528  * be able to use wakeup events to exit from runtime low-power states,
529  * or from system low-power states such as standby or suspend-to-RAM.
530  */
531 
532 #ifdef CONFIG_PM_SLEEP
533 #ifndef CONFIG_ARCH_NO_SYSDEV_OPS
534 extern int sysdev_suspend(pm_message_t state);
535 extern int sysdev_resume(void);
536 #else
537 static inline int sysdev_suspend(pm_message_t state) { return 0; }
538 static inline int sysdev_resume(void) { return 0; }
539 #endif
540 
541 extern void device_pm_lock(void);
542 extern void dpm_resume_noirq(pm_message_t state);
543 extern void dpm_resume_end(pm_message_t state);
544 
545 extern void device_pm_unlock(void);
546 extern int dpm_suspend_noirq(pm_message_t state);
547 extern int dpm_suspend_start(pm_message_t state);
548 
549 extern void __suspend_report_result(const char *function, void *fn, int ret);
550 
551 #define suspend_report_result(fn, ret)                                  \
552         do {                                                            \
553                 __suspend_report_result(__func__, fn, ret);             \
554         } while (0)
555 
556 extern int device_pm_wait_for_dev(struct device *sub, struct device *dev);
557 #else /* !CONFIG_PM_SLEEP */
558 
559 #define device_pm_lock() do {} while (0)
560 #define device_pm_unlock() do {} while (0)
561 
562 static inline int dpm_suspend_start(pm_message_t state)
563 {
564         return 0;
565 }
566 
567 #define suspend_report_result(fn, ret)          do {} while (0)
568 
569 static inline int device_pm_wait_for_dev(struct device *a, struct device *b)
570 {
571         return 0;
572 }
573 #endif /* !CONFIG_PM_SLEEP */
574 
575 /* How to reorder dpm_list after device_move() */
576 enum dpm_order {
577         DPM_ORDER_NONE,
578         DPM_ORDER_DEV_AFTER_PARENT,
579         DPM_ORDER_PARENT_BEFORE_DEV,
580         DPM_ORDER_DEV_LAST,
581 };
582 
583 extern int pm_generic_suspend(struct device *dev);
584 extern int pm_generic_resume(struct device *dev);
585 extern int pm_generic_freeze(struct device *dev);
586 extern int pm_generic_thaw(struct device *dev);
587 extern int pm_generic_restore(struct device *dev);
588 extern int pm_generic_poweroff(struct device *dev);
589 
590 #endif /* _LINUX_PM_H */
591 

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