include/linux/pm.h

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