include/linux/suspend.h

   1 #ifndef _LINUX_SUSPEND_H
   2 #define _LINUX_SUSPEND_H
   3
   4 #include <linux/swap.h>
   5 #include <linux/notifier.h>
   6 #include <linux/init.h>
   7 #include <linux/pm.h>
   8 #include <linux/mm.h>
   9 #include <linux/freezer.h>
  10 #include <asm/errno.h>
  11
  12 #ifdef CONFIG_VT
  13 extern void pm_set_vt_switch(int);
  14 #else
  15 static inline void pm_set_vt_switch(int do_switch)
  16 {
  17 }
  18 #endif
  19
  20 #ifdef CONFIG_VT_CONSOLE_SLEEP
  21 extern int pm_prepare_console(void);
  22 extern void pm_restore_console(void);
  23 #else
  24 static inline int pm_prepare_console(void)
  25 {
  26         return 0;
  27 }
  28
  29 static inline void pm_restore_console(void)
  30 {
  31 }
  32 #endif
  33
  34 typedef int __bitwise suspend_state_t;
  35
  36 #define PM_SUSPEND_ON           ((__force suspend_state_t) 0)
  37 #define PM_SUSPEND_FREEZE       ((__force suspend_state_t) 1)
  38 #define PM_SUSPEND_STANDBY      ((__force suspend_state_t) 2)
  39 #define PM_SUSPEND_MEM          ((__force suspend_state_t) 3)
  40 #define PM_SUSPEND_MIN          PM_SUSPEND_FREEZE
  41 #define PM_SUSPEND_MAX          ((__force suspend_state_t) 4)
  42
  43 enum suspend_stat_step {
  44         SUSPEND_FREEZE = 1,
  45         SUSPEND_PREPARE,
  46         SUSPEND_SUSPEND,
  47         SUSPEND_SUSPEND_LATE,
  48         SUSPEND_SUSPEND_NOIRQ,
  49         SUSPEND_RESUME_NOIRQ,
  50         SUSPEND_RESUME_EARLY,
  51         SUSPEND_RESUME
  52 };
  53
  54 struct suspend_stats {
  55         int     success;
  56         int     fail;
  57         int     failed_freeze;
  58         int     failed_prepare;
  59         int     failed_suspend;
  60         int     failed_suspend_late;
  61         int     failed_suspend_noirq;
  62         int     failed_resume;
  63         int     failed_resume_early;
  64         int     failed_resume_noirq;
  65 #define REC_FAILED_NUM  2
  66         int     last_failed_dev;
  67         char    failed_devs[REC_FAILED_NUM][40];
  68         int     last_failed_errno;
  69         int     errno[REC_FAILED_NUM];
  70         int     last_failed_step;
  71         enum suspend_stat_step  failed_steps[REC_FAILED_NUM];
  72 };
  73
  74 extern struct suspend_stats suspend_stats;
  75
  76 static inline void dpm_save_failed_dev(const char *name)
  77 {
  78         strlcpy(suspend_stats.failed_devs[suspend_stats.last_failed_dev],
  79                 name,
  80                 sizeof(suspend_stats.failed_devs[0]));
  81         suspend_stats.last_failed_dev++;
  82         suspend_stats.last_failed_dev %= REC_FAILED_NUM;
  83 }
  84
  85 static inline void dpm_save_failed_errno(int err)
  86 {
  87         suspend_stats.errno[suspend_stats.last_failed_errno] = err;
  88         suspend_stats.last_failed_errno++;
  89         suspend_stats.last_failed_errno %= REC_FAILED_NUM;
  90 }
  91
  92 static inline void dpm_save_failed_step(enum suspend_stat_step step)
  93 {
  94         suspend_stats.failed_steps[suspend_stats.last_failed_step] = step;
  95         suspend_stats.last_failed_step++;
  96         suspend_stats.last_failed_step %= REC_FAILED_NUM;
  97 }
  98
  99 /**
 100  * struct platform_suspend_ops - Callbacks for managing platform dependent
 101  *      system sleep states.
 102  *
 103  * @valid: Callback to determine if given system sleep state is supported by
 104  *      the platform.
 105  *      Valid (ie. supported) states are advertised in /sys/power/state.  Note
 106  *      that it still may be impossible to enter given system sleep state if the
 107  *      conditions aren't right.
 108  *      There is the %suspend_valid_only_mem function available that can be
 109  *      assigned to this if the platform only supports mem sleep.
 110  *
 111  * @begin: Initialise a transition to given system sleep state.
 112  *      @begin() is executed right prior to suspending devices.  The information
 113  *      conveyed to the platform code by @begin() should be disregarded by it as
 114  *      soon as @end() is executed.  If @begin() fails (ie. returns nonzero),
 115  *      @prepare(), @enter() and @finish() will not be called by the PM core.
 116  *      This callback is optional.  However, if it is implemented, the argument
 117  *      passed to @enter() is redundant and should be ignored.
 118  *
 119  * @prepare: Prepare the platform for entering the system sleep state indicated
 120  *      by @begin().
 121  *      @prepare() is called right after devices have been suspended (ie. the
 122  *      appropriate .suspend() method has been executed for each device) and
 123  *      before device drivers' late suspend callbacks are executed.  It returns
 124  *      0 on success or a negative error code otherwise, in which case the
 125  *      system cannot enter the desired sleep state (@prepare_late(), @enter(),
 126  *      and @wake() will not be called in that case).
 127  *
 128  * @prepare_late: Finish preparing the platform for entering the system sleep
 129  *      state indicated by @begin().
 130  *      @prepare_late is called before disabling nonboot CPUs and after
 131  *      device drivers' late suspend callbacks have been executed.  It returns
 132  *      0 on success or a negative error code otherwise, in which case the
 133  *      system cannot enter the desired sleep state (@enter() will not be
 134  *      executed).
 135  *
 136  * @enter: Enter the system sleep state indicated by @begin() or represented by
 137  *      the argument if @begin() is not implemented.
 138  *      This callback is mandatory.  It returns 0 on success or a negative
 139  *      error code otherwise, in which case the system cannot enter the desired
 140  *      sleep state.
 141  *
 142  * @wake: Called when the system has just left a sleep state, right after
 143  *      the nonboot CPUs have been enabled and before device drivers' early
 144  *      resume callbacks are executed.
 145  *      This callback is optional, but should be implemented by the platforms
 146  *      that implement @prepare_late().  If implemented, it is always called
 147  *      after @prepare_late and @enter(), even if one of them fails.
 148  *
 149  * @finish: Finish wake-up of the platform.
 150  *      @finish is called right prior to calling device drivers' regular suspend
 151  *      callbacks.
 152  *      This callback is optional, but should be implemented by the platforms
 153  *      that implement @prepare().  If implemented, it is always called after
 154  *      @enter() and @wake(), even if any of them fails.  It is executed after
 155  *      a failing @prepare.
 156  *
 157  * @suspend_again: Returns whether the system should suspend again (true) or
 158  *      not (false). If the platform wants to poll sensors or execute some
 159  *      code during suspended without invoking userspace and most of devices,
 160  *      suspend_again callback is the place assuming that periodic-wakeup or
 161  *      alarm-wakeup is already setup. This allows to execute some codes while
 162  *      being kept suspended in the view of userland and devices.
 163  *
 164  * @end: Called by the PM core right after resuming devices, to indicate to
 165  *      the platform that the system has returned to the working state or
 166  *      the transition to the sleep state has been aborted.
 167  *      This callback is optional, but should be implemented by the platforms
 168  *      that implement @begin().  Accordingly, platforms implementing @begin()
 169  *      should also provide a @end() which cleans up transitions aborted before
 170  *      @enter().
 171  *
 172  * @recover: Recover the platform from a suspend failure.
 173  *      Called by the PM core if the suspending of devices fails.
 174  *      This callback is optional and should only be implemented by platforms
 175  *      which require special recovery actions in that situation.
 176  */
 177 struct platform_suspend_ops {
 178         int (*valid)(suspend_state_t state);
 179         int (*begin)(suspend_state_t state);
 180         int (*prepare)(void);
 181         int (*prepare_late)(void);
 182         int (*enter)(suspend_state_t state);
 183         void (*wake)(void);
 184         void (*finish)(void);
 185         bool (*suspend_again)(void);
 186         void (*end)(void);
 187         void (*recover)(void);
 188 };
 189
 190 struct platform_freeze_ops {
 191         int (*begin)(void);
 192         int (*prepare)(void);
 193         void (*restore)(void);
 194         void (*end)(void);
 195 };
 196
 197 #ifdef CONFIG_SUSPEND
 198 /**
 199  * suspend_set_ops - set platform dependent suspend operations
 200  * @ops: The new suspend operations to set.
 201  */
 202 extern void suspend_set_ops(const struct platform_suspend_ops *ops);
 203 extern int suspend_valid_only_mem(suspend_state_t state);
 204
 205 /* Suspend-to-idle state machnine. */
 206 enum freeze_state {
 207         FREEZE_STATE_NONE,      /* Not suspended/suspending. */
 208         FREEZE_STATE_ENTER,     /* Enter suspend-to-idle. */
 209         FREEZE_STATE_WAKE,      /* Wake up from suspend-to-idle. */
 210 };
 211
 212 extern enum freeze_state __read_mostly suspend_freeze_state;
 213
 214 static inline bool idle_should_freeze(void)
 215 {
 216         return unlikely(suspend_freeze_state == FREEZE_STATE_ENTER);
 217 }
 218
 219 extern void freeze_set_ops(const struct platform_freeze_ops *ops);
 220 extern void freeze_wake(void);
 221
 222 /**
 223  * arch_suspend_disable_irqs - disable IRQs for suspend
 224  *
 225  * Disables IRQs (in the default case). This is a weak symbol in the common
 226  * code and thus allows architectures to override it if more needs to be
 227  * done. Not called for suspend to disk.
 228  */
 229 extern void arch_suspend_disable_irqs(void);
 230
 231 /**
 232  * arch_suspend_enable_irqs - enable IRQs after suspend
 233  *
 234  * Enables IRQs (in the default case). This is a weak symbol in the common
 235  * code and thus allows architectures to override it if more needs to be
 236  * done. Not called for suspend to disk.
 237  */
 238 extern void arch_suspend_enable_irqs(void);
 239
 240 extern int pm_suspend(suspend_state_t state);
 241 #else /* !CONFIG_SUSPEND */
 242 #define suspend_valid_only_mem  NULL
 243
 244 static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {}
 245 static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
 246 static inline bool idle_should_freeze(void) { return false; }
 247 static inline void freeze_set_ops(const struct platform_freeze_ops *ops) {}
 248 static inline void freeze_wake(void) {}
 249 #endif /* !CONFIG_SUSPEND */
 250
 251 /* struct pbe is used for creating lists of pages that should be restored
 252  * atomically during the resume from disk, because the page frames they have
 253  * occupied before the suspend are in use.
 254  */
 255 struct pbe {
 256         void *address;          /* address of the copy */
 257         void *orig_address;     /* original address of a page */
 258         struct pbe *next;
 259 };
 260
 261 /* mm/page_alloc.c */
 262 extern void mark_free_pages(struct zone *zone);
 263
 264 /**
 265  * struct platform_hibernation_ops - hibernation platform support
 266  *
 267  * The methods in this structure allow a platform to carry out special
 268  * operations required by it during a hibernation transition.
 269  *
 270  * All the methods below, except for @recover(), must be implemented.
 271  *
 272  * @begin: Tell the platform driver that we're starting hibernation.
 273  *      Called right after shrinking memory and before freezing devices.
 274  *
 275  * @end: Called by the PM core right after resuming devices, to indicate to
 276  *      the platform that the system has returned to the working state.
 277  *
 278  * @pre_snapshot: Prepare the platform for creating the hibernation image.
 279  *      Called right after devices have been frozen and before the nonboot
 280  *      CPUs are disabled (runs with IRQs on).
 281  *
 282  * @finish: Restore the previous state of the platform after the hibernation
 283  *      image has been created *or* put the platform into the normal operation
 284  *      mode after the hibernation (the same method is executed in both cases).
 285  *      Called right after the nonboot CPUs have been enabled and before
 286  *      thawing devices (runs with IRQs on).
 287  *
 288  * @prepare: Prepare the platform for entering the low power state.
 289  *      Called right after the hibernation image has been saved and before
 290  *      devices are prepared for entering the low power state.
 291  *
 292  * @enter: Put the system into the low power state after the hibernation image
 293  *      has been saved to disk.
 294  *      Called after the nonboot CPUs have been disabled and all of the low
 295  *      level devices have been shut down (runs with IRQs off).
 296  *
 297  * @leave: Perform the first stage of the cleanup after the system sleep state
 298  *      indicated by @set_target() has been left.
 299  *      Called right after the control has been passed from the boot kernel to
 300  *      the image kernel, before the nonboot CPUs are enabled and before devices
 301  *      are resumed.  Executed with interrupts disabled.
 302  *
 303  * @pre_restore: Prepare system for the restoration from a hibernation image.
 304  *      Called right after devices have been frozen and before the nonboot
 305  *      CPUs are disabled (runs with IRQs on).
 306  *
 307  * @restore_cleanup: Clean up after a failing image restoration.
 308  *      Called right after the nonboot CPUs have been enabled and before
 309  *      thawing devices (runs with IRQs on).
 310  *
 311  * @recover: Recover the platform from a failure to suspend devices.
 312  *      Called by the PM core if the suspending of devices during hibernation
 313  *      fails.  This callback is optional and should only be implemented by
 314  *      platforms which require special recovery actions in that situation.
 315  */
 316 struct platform_hibernation_ops {
 317         int (*begin)(void);
 318         void (*end)(void);
 319         int (*pre_snapshot)(void);
 320         void (*finish)(void);
 321         int (*prepare)(void);
 322         int (*enter)(void);
 323         void (*leave)(void);
 324         int (*pre_restore)(void);
 325         void (*restore_cleanup)(void);
 326         void (*recover)(void);
 327 };
 328
 329 #ifdef CONFIG_HIBERNATION
 330 /* kernel/power/snapshot.c */
 331 extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
 332 static inline void __init register_nosave_region(unsigned long b, unsigned long e)
 333 {
 334         __register_nosave_region(b, e, 0);
 335 }
 336 static inline void __init register_nosave_region_late(unsigned long b, unsigned long e)
 337 {
 338         __register_nosave_region(b, e, 1);
 339 }
 340 extern int swsusp_page_is_forbidden(struct page *);
 341 extern void swsusp_set_page_free(struct page *);
 342 extern void swsusp_unset_page_free(struct page *);
 343 extern unsigned long get_safe_page(gfp_t gfp_mask);
 344
 345 extern void hibernation_set_ops(const struct platform_hibernation_ops *ops);
 346 extern int hibernate(void);
 347 extern bool system_entering_hibernation(void);
 348 extern bool hibernation_available(void);
 349 asmlinkage int swsusp_save(void);
 350 extern struct pbe *restore_pblist;
 351 #else /* CONFIG_HIBERNATION */
 352 static inline void register_nosave_region(unsigned long b, unsigned long e) {}
 353 static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
 354 static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
 355 static inline void swsusp_set_page_free(struct page *p) {}
 356 static inline void swsusp_unset_page_free(struct page *p) {}
 357
 358 static inline void hibernation_set_ops(const struct platform_hibernation_ops *ops) {}
 359 static inline int hibernate(void) { return -ENOSYS; }
 360 static inline bool system_entering_hibernation(void) { return false; }
 361 static inline bool hibernation_available(void) { return false; }
 362 #endif /* CONFIG_HIBERNATION */
 363
 364 /* Hibernation and suspend events */
 365 #define PM_HIBERNATION_PREPARE  0x0001 /* Going to hibernate */
 366 #define PM_POST_HIBERNATION     0x0002 /* Hibernation finished */
 367 #define PM_SUSPEND_PREPARE      0x0003 /* Going to suspend the system */
 368 #define PM_POST_SUSPEND         0x0004 /* Suspend finished */
 369 #define PM_RESTORE_PREPARE      0x0005 /* Going to restore a saved image */
 370 #define PM_POST_RESTORE         0x0006 /* Restore failed */
 371
 372 extern struct mutex pm_mutex;
 373
 374 #ifdef CONFIG_PM_SLEEP
 375 void save_processor_state(void);
 376 void restore_processor_state(void);
 377
 378 /* kernel/power/main.c */
 379 extern int register_pm_notifier(struct notifier_block *nb);
 380 extern int unregister_pm_notifier(struct notifier_block *nb);
 381
 382 #define pm_notifier(fn, pri) {                          \
 383         static struct notifier_block fn##_nb =                  \
 384                 { .notifier_call = fn, .priority = pri };       \
 385         register_pm_notifier(&fn##_nb);                 \
 386 }
 387
 388 /* drivers/base/power/wakeup.c */
 389 extern bool events_check_enabled;
 390
 391 extern bool pm_wakeup_pending(void);
 392 extern void pm_system_wakeup(void);
 393 extern void pm_wakeup_clear(void);
 394 extern bool pm_get_wakeup_count(unsigned int *count, bool block);
 395 extern bool pm_save_wakeup_count(unsigned int count);
 396 extern void pm_wakep_autosleep_enabled(bool set);
 397 extern void pm_print_active_wakeup_sources(void);
 398
 399 static inline void lock_system_sleep(void)
 400 {
 401         current->flags |= PF_FREEZER_SKIP;
 402         mutex_lock(&pm_mutex);
 403 }
 404
 405 static inline void unlock_system_sleep(void)
 406 {
 407         /*
 408          * Don't use freezer_count() because we don't want the call to
 409          * try_to_freeze() here.
 410          *
 411          * Reason:
 412          * Fundamentally, we just don't need it, because freezing condition
 413          * doesn't come into effect until we release the pm_mutex lock,
 414          * since the freezer always works with pm_mutex held.
 415          *
 416          * More importantly, in the case of hibernation,
 417          * unlock_system_sleep() gets called in snapshot_read() and
 418          * snapshot_write() when the freezing condition is still in effect.
 419          * Which means, if we use try_to_freeze() here, it would make them
 420          * enter the refrigerator, thus causing hibernation to lockup.
 421          */
 422         current->flags &= ~PF_FREEZER_SKIP;
 423         mutex_unlock(&pm_mutex);
 424 }
 425
 426 #else /* !CONFIG_PM_SLEEP */
 427
 428 static inline int register_pm_notifier(struct notifier_block *nb)
 429 {
 430         return 0;
 431 }
 432
 433 static inline int unregister_pm_notifier(struct notifier_block *nb)
 434 {
 435         return 0;
 436 }
 437
 438 #define pm_notifier(fn, pri)    do { (void)(fn); } while (0)
 439
 440 static inline bool pm_wakeup_pending(void) { return false; }
 441 static inline void pm_system_wakeup(void) {}
 442 static inline void pm_wakeup_clear(void) {}
 443
 444 static inline void lock_system_sleep(void) {}
 445 static inline void unlock_system_sleep(void) {}
 446
 447 #endif /* !CONFIG_PM_SLEEP */
 448
 449 #ifdef CONFIG_PM_SLEEP_DEBUG
 450 extern bool pm_print_times_enabled;
 451 #else
 452 #define pm_print_times_enabled  (false)
 453 #endif
 454
 455 #ifdef CONFIG_PM_AUTOSLEEP
 456
 457 /* kernel/power/autosleep.c */
 458 void queue_up_suspend_work(void);
 459
 460 #else /* !CONFIG_PM_AUTOSLEEP */
 461
 462 static inline void queue_up_suspend_work(void) {}
 463
 464 #endif /* !CONFIG_PM_AUTOSLEEP */
 465
 466 #ifdef CONFIG_ARCH_SAVE_PAGE_KEYS
 467 /*
 468  * The ARCH_SAVE_PAGE_KEYS functions can be used by an architecture
 469  * to save/restore additional information to/from the array of page
 470  * frame numbers in the hibernation image. For s390 this is used to
 471  * save and restore the storage key for each page that is included
 472  * in the hibernation image.
 473  */
 474 unsigned long page_key_additional_pages(unsigned long pages);
 475 int page_key_alloc(unsigned long pages);
 476 void page_key_free(void);
 477 void page_key_read(unsigned long *pfn);
 478 void page_key_memorize(unsigned long *pfn);
 479 void page_key_write(void *address);
 480
 481 #else /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
 482
 483 static inline unsigned long page_key_additional_pages(unsigned long pages)
 484 {
 485         return 0;
 486 }
 487
 488 static inline int  page_key_alloc(unsigned long pages)
 489 {
 490         return 0;
 491 }
 492
 493 static inline void page_key_free(void) {}
 494 static inline void page_key_read(unsigned long *pfn) {}
 495 static inline void page_key_memorize(unsigned long *pfn) {}
 496 static inline void page_key_write(void *address) {}
 497
 498 #endif /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
 499
 500 #endif /* _LINUX_SUSPEND_H */