include/linux/suspend.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_SUSPEND_H
   3 #define _LINUX_SUSPEND_H
   4
   5 #include <linux/swap.h>
   6 #include <linux/notifier.h>
   7 #include <linux/init.h>
   8 #include <linux/pm.h>
   9 #include <linux/mm.h>
  10 #include <linux/freezer.h>
  11 #include <asm/errno.h>
  12
  13 #ifdef CONFIG_VT
  14 extern void pm_set_vt_switch(int);
  15 #else
  16 static inline void pm_set_vt_switch(int do_switch)
  17 {
  18 }
  19 #endif
  20
  21 #ifdef CONFIG_VT_CONSOLE_SLEEP
  22 extern void pm_prepare_console(void);
  23 extern void pm_restore_console(void);
  24 #else
  25 static inline void pm_prepare_console(void)
  26 {
  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_TO_IDLE      ((__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_TO_IDLE
  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_s2idle_ops {
 191         int (*begin)(void);
 192         int (*prepare)(void);
 193         void (*wake)(void);
 194         void (*sync)(void);
 195         void (*restore)(void);
 196         void (*end)(void);
 197 };
 198
 199 #ifdef CONFIG_SUSPEND
 200 extern suspend_state_t mem_sleep_current;
 201 extern suspend_state_t mem_sleep_default;
 202
 203 /**
 204  * suspend_set_ops - set platform dependent suspend operations
 205  * @ops: The new suspend operations to set.
 206  */
 207 extern void suspend_set_ops(const struct platform_suspend_ops *ops);
 208 extern int suspend_valid_only_mem(suspend_state_t state);
 209
 210 extern unsigned int pm_suspend_global_flags;
 211
 212 #define PM_SUSPEND_FLAG_FW_SUSPEND      (1 << 0)
 213 #define PM_SUSPEND_FLAG_FW_RESUME       (1 << 1)
 214
 215 static inline void pm_suspend_clear_flags(void)
 216 {
 217         pm_suspend_global_flags = 0;
 218 }
 219
 220 static inline void pm_set_suspend_via_firmware(void)
 221 {
 222         pm_suspend_global_flags |= PM_SUSPEND_FLAG_FW_SUSPEND;
 223 }
 224
 225 static inline void pm_set_resume_via_firmware(void)
 226 {
 227         pm_suspend_global_flags |= PM_SUSPEND_FLAG_FW_RESUME;
 228 }
 229
 230 static inline bool pm_suspend_via_firmware(void)
 231 {
 232         return !!(pm_suspend_global_flags & PM_SUSPEND_FLAG_FW_SUSPEND);
 233 }
 234
 235 static inline bool pm_resume_via_firmware(void)
 236 {
 237         return !!(pm_suspend_global_flags & PM_SUSPEND_FLAG_FW_RESUME);
 238 }
 239
 240 /* Suspend-to-idle state machnine. */
 241 enum s2idle_states {
 242         S2IDLE_STATE_NONE,      /* Not suspended/suspending. */
 243         S2IDLE_STATE_ENTER,     /* Enter suspend-to-idle. */
 244         S2IDLE_STATE_WAKE,      /* Wake up from suspend-to-idle. */
 245 };
 246
 247 extern enum s2idle_states __read_mostly s2idle_state;
 248
 249 static inline bool idle_should_enter_s2idle(void)
 250 {
 251         return unlikely(s2idle_state == S2IDLE_STATE_ENTER);
 252 }
 253
 254 extern bool pm_suspend_via_s2idle(void);
 255 extern void __init pm_states_init(void);
 256 extern void s2idle_set_ops(const struct platform_s2idle_ops *ops);
 257 extern void s2idle_wake(void);
 258
 259 /**
 260  * arch_suspend_disable_irqs - disable IRQs for suspend
 261  *
 262  * Disables IRQs (in the default case). This is a weak symbol in the common
 263  * code and thus allows architectures to override it if more needs to be
 264  * done. Not called for suspend to disk.
 265  */
 266 extern void arch_suspend_disable_irqs(void);
 267
 268 /**
 269  * arch_suspend_enable_irqs - enable IRQs after suspend
 270  *
 271  * Enables IRQs (in the default case). This is a weak symbol in the common
 272  * code and thus allows architectures to override it if more needs to be
 273  * done. Not called for suspend to disk.
 274  */
 275 extern void arch_suspend_enable_irqs(void);
 276
 277 extern int pm_suspend(suspend_state_t state);
 278 #else /* !CONFIG_SUSPEND */
 279 #define suspend_valid_only_mem  NULL
 280
 281 static inline void pm_suspend_clear_flags(void) {}
 282 static inline void pm_set_suspend_via_firmware(void) {}
 283 static inline void pm_set_resume_via_firmware(void) {}
 284 static inline bool pm_suspend_via_firmware(void) { return false; }
 285 static inline bool pm_resume_via_firmware(void) { return false; }
 286 static inline bool pm_suspend_via_s2idle(void) { return false; }
 287
 288 static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {}
 289 static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
 290 static inline bool idle_should_enter_s2idle(void) { return false; }
 291 static inline void __init pm_states_init(void) {}
 292 static inline void s2idle_set_ops(const struct platform_s2idle_ops *ops) {}
 293 static inline void s2idle_wake(void) {}
 294 #endif /* !CONFIG_SUSPEND */
 295
 296 /* struct pbe is used for creating lists of pages that should be restored
 297  * atomically during the resume from disk, because the page frames they have
 298  * occupied before the suspend are in use.
 299  */
 300 struct pbe {
 301         void *address;          /* address of the copy */
 302         void *orig_address;     /* original address of a page */
 303         struct pbe *next;
 304 };
 305
 306 /* mm/page_alloc.c */
 307 extern void mark_free_pages(struct zone *zone);
 308
 309 /**
 310  * struct platform_hibernation_ops - hibernation platform support
 311  *
 312  * The methods in this structure allow a platform to carry out special
 313  * operations required by it during a hibernation transition.
 314  *
 315  * All the methods below, except for @recover(), must be implemented.
 316  *
 317  * @begin: Tell the platform driver that we're starting hibernation.
 318  *      Called right after shrinking memory and before freezing devices.
 319  *
 320  * @end: Called by the PM core right after resuming devices, to indicate to
 321  *      the platform that the system has returned to the working state.
 322  *
 323  * @pre_snapshot: Prepare the platform for creating the hibernation image.
 324  *      Called right after devices have been frozen and before the nonboot
 325  *      CPUs are disabled (runs with IRQs on).
 326  *
 327  * @finish: Restore the previous state of the platform after the hibernation
 328  *      image has been created *or* put the platform into the normal operation
 329  *      mode after the hibernation (the same method is executed in both cases).
 330  *      Called right after the nonboot CPUs have been enabled and before
 331  *      thawing devices (runs with IRQs on).
 332  *
 333  * @prepare: Prepare the platform for entering the low power state.
 334  *      Called right after the hibernation image has been saved and before
 335  *      devices are prepared for entering the low power state.
 336  *
 337  * @enter: Put the system into the low power state after the hibernation image
 338  *      has been saved to disk.
 339  *      Called after the nonboot CPUs have been disabled and all of the low
 340  *      level devices have been shut down (runs with IRQs off).
 341  *
 342  * @leave: Perform the first stage of the cleanup after the system sleep state
 343  *      indicated by @set_target() has been left.
 344  *      Called right after the control has been passed from the boot kernel to
 345  *      the image kernel, before the nonboot CPUs are enabled and before devices
 346  *      are resumed.  Executed with interrupts disabled.
 347  *
 348  * @pre_restore: Prepare system for the restoration from a hibernation image.
 349  *      Called right after devices have been frozen and before the nonboot
 350  *      CPUs are disabled (runs with IRQs on).
 351  *
 352  * @restore_cleanup: Clean up after a failing image restoration.
 353  *      Called right after the nonboot CPUs have been enabled and before
 354  *      thawing devices (runs with IRQs on).
 355  *
 356  * @recover: Recover the platform from a failure to suspend devices.
 357  *      Called by the PM core if the suspending of devices during hibernation
 358  *      fails.  This callback is optional and should only be implemented by
 359  *      platforms which require special recovery actions in that situation.
 360  */
 361 struct platform_hibernation_ops {
 362         int (*begin)(void);
 363         void (*end)(void);
 364         int (*pre_snapshot)(void);
 365         void (*finish)(void);
 366         int (*prepare)(void);
 367         int (*enter)(void);
 368         void (*leave)(void);
 369         int (*pre_restore)(void);
 370         void (*restore_cleanup)(void);
 371         void (*recover)(void);
 372 };
 373
 374 #ifdef CONFIG_HIBERNATION
 375 /* kernel/power/snapshot.c */
 376 extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
 377 static inline void __init register_nosave_region(unsigned long b, unsigned long e)
 378 {
 379         __register_nosave_region(b, e, 0);
 380 }
 381 static inline void __init register_nosave_region_late(unsigned long b, unsigned long e)
 382 {
 383         __register_nosave_region(b, e, 1);
 384 }
 385 extern int swsusp_page_is_forbidden(struct page *);
 386 extern void swsusp_set_page_free(struct page *);
 387 extern void swsusp_unset_page_free(struct page *);
 388 extern unsigned long get_safe_page(gfp_t gfp_mask);
 389 extern asmlinkage int swsusp_arch_suspend(void);
 390 extern asmlinkage int swsusp_arch_resume(void);
 391
 392 extern void hibernation_set_ops(const struct platform_hibernation_ops *ops);
 393 extern int hibernate(void);
 394 extern bool system_entering_hibernation(void);
 395 extern bool hibernation_available(void);
 396 asmlinkage int swsusp_save(void);
 397 extern struct pbe *restore_pblist;
 398 #else /* CONFIG_HIBERNATION */
 399 static inline void register_nosave_region(unsigned long b, unsigned long e) {}
 400 static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
 401 static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
 402 static inline void swsusp_set_page_free(struct page *p) {}
 403 static inline void swsusp_unset_page_free(struct page *p) {}
 404
 405 static inline void hibernation_set_ops(const struct platform_hibernation_ops *ops) {}
 406 static inline int hibernate(void) { return -ENOSYS; }
 407 static inline bool system_entering_hibernation(void) { return false; }
 408 static inline bool hibernation_available(void) { return false; }
 409 #endif /* CONFIG_HIBERNATION */
 410
 411 /* Hibernation and suspend events */
 412 #define PM_HIBERNATION_PREPARE  0x0001 /* Going to hibernate */
 413 #define PM_POST_HIBERNATION     0x0002 /* Hibernation finished */
 414 #define PM_SUSPEND_PREPARE      0x0003 /* Going to suspend the system */
 415 #define PM_POST_SUSPEND         0x0004 /* Suspend finished */
 416 #define PM_RESTORE_PREPARE      0x0005 /* Going to restore a saved image */
 417 #define PM_POST_RESTORE         0x0006 /* Restore failed */
 418
 419 extern struct mutex pm_mutex;
 420
 421 #ifdef CONFIG_PM_SLEEP
 422 void save_processor_state(void);
 423 void restore_processor_state(void);
 424
 425 /* kernel/power/main.c */
 426 extern int register_pm_notifier(struct notifier_block *nb);
 427 extern int unregister_pm_notifier(struct notifier_block *nb);
 428
 429 #define pm_notifier(fn, pri) {                          \
 430         static struct notifier_block fn##_nb =                  \
 431                 { .notifier_call = fn, .priority = pri };       \
 432         register_pm_notifier(&fn##_nb);                 \
 433 }
 434
 435 /* drivers/base/power/wakeup.c */
 436 extern bool events_check_enabled;
 437 extern unsigned int pm_wakeup_irq;
 438 extern suspend_state_t pm_suspend_target_state;
 439
 440 extern bool pm_wakeup_pending(void);
 441 extern void pm_system_wakeup(void);
 442 extern void pm_system_cancel_wakeup(void);
 443 extern void pm_wakeup_clear(bool reset);
 444 extern void pm_system_irq_wakeup(unsigned int irq_number);
 445 extern bool pm_get_wakeup_count(unsigned int *count, bool block);
 446 extern bool pm_save_wakeup_count(unsigned int count);
 447 extern void pm_wakep_autosleep_enabled(bool set);
 448 extern void pm_print_active_wakeup_sources(void);
 449
 450 static inline void lock_system_sleep(void)
 451 {
 452         current->flags |= PF_FREEZER_SKIP;
 453         mutex_lock(&pm_mutex);
 454 }
 455
 456 static inline void unlock_system_sleep(void)
 457 {
 458         /*
 459          * Don't use freezer_count() because we don't want the call to
 460          * try_to_freeze() here.
 461          *
 462          * Reason:
 463          * Fundamentally, we just don't need it, because freezing condition
 464          * doesn't come into effect until we release the pm_mutex lock,
 465          * since the freezer always works with pm_mutex held.
 466          *
 467          * More importantly, in the case of hibernation,
 468          * unlock_system_sleep() gets called in snapshot_read() and
 469          * snapshot_write() when the freezing condition is still in effect.
 470          * Which means, if we use try_to_freeze() here, it would make them
 471          * enter the refrigerator, thus causing hibernation to lockup.
 472          */
 473         current->flags &= ~PF_FREEZER_SKIP;
 474         mutex_unlock(&pm_mutex);
 475 }
 476
 477 #else /* !CONFIG_PM_SLEEP */
 478
 479 static inline int register_pm_notifier(struct notifier_block *nb)
 480 {
 481         return 0;
 482 }
 483
 484 static inline int unregister_pm_notifier(struct notifier_block *nb)
 485 {
 486         return 0;
 487 }
 488
 489 #define pm_notifier(fn, pri)    do { (void)(fn); } while (0)
 490
 491 static inline bool pm_wakeup_pending(void) { return false; }
 492 static inline void pm_system_wakeup(void) {}
 493 static inline void pm_wakeup_clear(bool reset) {}
 494 static inline void pm_system_irq_wakeup(unsigned int irq_number) {}
 495
 496 static inline void lock_system_sleep(void) {}
 497 static inline void unlock_system_sleep(void) {}
 498
 499 #endif /* !CONFIG_PM_SLEEP */
 500
 501 #ifdef CONFIG_PM_SLEEP_DEBUG
 502 extern bool pm_print_times_enabled;
 503 extern bool pm_debug_messages_on;
 504 extern __printf(2, 3) void __pm_pr_dbg(bool defer, const char *fmt, ...);
 505 #else
 506 #define pm_print_times_enabled  (false)
 507 #define pm_debug_messages_on    (false)
 508
 509 #include <linux/printk.h>
 510
 511 #define __pm_pr_dbg(defer, fmt, ...) \
 512         no_printk(KERN_DEBUG fmt, ##__VA_ARGS__)
 513 #endif
 514
 515 #define pm_pr_dbg(fmt, ...) \
 516         __pm_pr_dbg(false, fmt, ##__VA_ARGS__)
 517
 518 #define pm_deferred_pr_dbg(fmt, ...) \
 519         __pm_pr_dbg(true, fmt, ##__VA_ARGS__)
 520
 521 #ifdef CONFIG_PM_AUTOSLEEP
 522
 523 /* kernel/power/autosleep.c */
 524 void queue_up_suspend_work(void);
 525
 526 #else /* !CONFIG_PM_AUTOSLEEP */
 527
 528 static inline void queue_up_suspend_work(void) {}
 529
 530 #endif /* !CONFIG_PM_AUTOSLEEP */
 531
 532 #ifdef CONFIG_ARCH_SAVE_PAGE_KEYS
 533 /*
 534  * The ARCH_SAVE_PAGE_KEYS functions can be used by an architecture
 535  * to save/restore additional information to/from the array of page
 536  * frame numbers in the hibernation image. For s390 this is used to
 537  * save and restore the storage key for each page that is included
 538  * in the hibernation image.
 539  */
 540 unsigned long page_key_additional_pages(unsigned long pages);
 541 int page_key_alloc(unsigned long pages);
 542 void page_key_free(void);
 543 void page_key_read(unsigned long *pfn);
 544 void page_key_memorize(unsigned long *pfn);
 545 void page_key_write(void *address);
 546
 547 #else /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
 548
 549 static inline unsigned long page_key_additional_pages(unsigned long pages)
 550 {
 551         return 0;
 552 }
 553
 554 static inline int  page_key_alloc(unsigned long pages)
 555 {
 556         return 0;
 557 }
 558
 559 static inline void page_key_free(void) {}
 560 static inline void page_key_read(unsigned long *pfn) {}
 561 static inline void page_key_memorize(unsigned long *pfn) {}
 562 static inline void page_key_write(void *address) {}
 563
 564 #endif /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
 565
 566 #endif /* _LINUX_SUSPEND_H */