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