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 <asm/errno.h>
  10
  11 #if defined(CONFIG_PM_SLEEP) && defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE)
  12 extern void pm_set_vt_switch(int);
  13 extern int pm_prepare_console(void);
  14 extern void pm_restore_console(void);
  15 #else
  16 static inline void pm_set_vt_switch(int do_switch)
  17 {
  18 }
  19
  20 static inline int pm_prepare_console(void)
  21 {
  22         return 0;
  23 }
  24
  25 static inline void pm_restore_console(void)
  26 {
  27 }
  28 #endif
  29
  30 typedef int __bitwise suspend_state_t;
  31
  32 #define PM_SUSPEND_ON           ((__force suspend_state_t) 0)
  33 #define PM_SUSPEND_STANDBY      ((__force suspend_state_t) 1)
  34 #define PM_SUSPEND_MEM          ((__force suspend_state_t) 3)
  35 #define PM_SUSPEND_MAX          ((__force suspend_state_t) 4)
  36
  37 /**
  38  * struct platform_suspend_ops - Callbacks for managing platform dependent
  39  *      system sleep states.
  40  *
  41  * @valid: Callback to determine if given system sleep state is supported by
  42  *      the platform.
  43  *      Valid (ie. supported) states are advertised in /sys/power/state.  Note
  44  *      that it still may be impossible to enter given system sleep state if the
  45  *      conditions aren't right.
  46  *      There is the %suspend_valid_only_mem function available that can be
  47  *      assigned to this if the platform only supports mem sleep.
  48  *
  49  * @begin: Initialise a transition to given system sleep state.
  50  *      @begin() is executed right prior to suspending devices.  The information
  51  *      conveyed to the platform code by @begin() should be disregarded by it as
  52  *      soon as @end() is executed.  If @begin() fails (ie. returns nonzero),
  53  *      @prepare(), @enter() and @finish() will not be called by the PM core.
  54  *      This callback is optional.  However, if it is implemented, the argument
  55  *      passed to @enter() is redundant and should be ignored.
  56  *
  57  * @prepare: Prepare the platform for entering the system sleep state indicated
  58  *      by @begin().
  59  *      @prepare() is called right after devices have been suspended (ie. the
  60  *      appropriate .suspend() method has been executed for each device) and
  61  *      before device drivers' late suspend callbacks are executed.  It returns
  62  *      0 on success or a negative error code otherwise, in which case the
  63  *      system cannot enter the desired sleep state (@prepare_late(), @enter(),
  64  *      and @wake() will not be called in that case).
  65  *
  66  * @prepare_late: Finish preparing the platform for entering the system sleep
  67  *      state indicated by @begin().
  68  *      @prepare_late is called before disabling nonboot CPUs and after
  69  *      device drivers' late suspend callbacks have been executed.  It returns
  70  *      0 on success or a negative error code otherwise, in which case the
  71  *      system cannot enter the desired sleep state (@enter() will not be
  72  *      executed).
  73  *
  74  * @enter: Enter the system sleep state indicated by @begin() or represented by
  75  *      the argument if @begin() is not implemented.
  76  *      This callback is mandatory.  It returns 0 on success or a negative
  77  *      error code otherwise, in which case the system cannot enter the desired
  78  *      sleep state.
  79  *
  80  * @wake: Called when the system has just left a sleep state, right after
  81  *      the nonboot CPUs have been enabled and before device drivers' early
  82  *      resume callbacks are executed.
  83  *      This callback is optional, but should be implemented by the platforms
  84  *      that implement @prepare_late().  If implemented, it is always called
  85  *      after @prepare_late and @enter(), even if one of them fails.
  86  *
  87  * @finish: Finish wake-up of the platform.
  88  *      @finish is called right prior to calling device drivers' regular suspend
  89  *      callbacks.
  90  *      This callback is optional, but should be implemented by the platforms
  91  *      that implement @prepare().  If implemented, it is always called after
  92  *      @enter() and @wake(), even if any of them fails.  It is executed after
  93  *      a failing @prepare.
  94  *
  95  * @suspend_again: Returns whether the system should suspend again (true) or
  96  *      not (false). If the platform wants to poll sensors or execute some
  97  *      code during suspended without invoking userspace and most of devices,
  98  *      suspend_again callback is the place assuming that periodic-wakeup or
  99  *      alarm-wakeup is already setup. This allows to execute some codes while
 100  *      being kept suspended in the view of userland and devices.
 101  *
 102  * @end: Called by the PM core right after resuming devices, to indicate to
 103  *      the platform that the system has returned to the working state or
 104  *      the transition to the sleep state has been aborted.
 105  *      This callback is optional, but should be implemented by the platforms
 106  *      that implement @begin().  Accordingly, platforms implementing @begin()
 107  *      should also provide a @end() which cleans up transitions aborted before
 108  *      @enter().
 109  *
 110  * @recover: Recover the platform from a suspend failure.
 111  *      Called by the PM core if the suspending of devices fails.
 112  *      This callback is optional and should only be implemented by platforms
 113  *      which require special recovery actions in that situation.
 114  */
 115 struct platform_suspend_ops {
 116         int (*valid)(suspend_state_t state);
 117         int (*begin)(suspend_state_t state);
 118         int (*prepare)(void);
 119         int (*prepare_late)(void);
 120         int (*enter)(suspend_state_t state);
 121         void (*wake)(void);
 122         void (*finish)(void);
 123         bool (*suspend_again)(void);
 124         void (*end)(void);
 125         void (*recover)(void);
 126 };
 127
 128 #ifdef CONFIG_SUSPEND
 129 /**
 130  * suspend_set_ops - set platform dependent suspend operations
 131  * @ops: The new suspend operations to set.
 132  */
 133 extern void suspend_set_ops(const struct platform_suspend_ops *ops);
 134 extern int suspend_valid_only_mem(suspend_state_t state);
 135
 136 /**
 137  * arch_suspend_disable_irqs - disable IRQs for suspend
 138  *
 139  * Disables IRQs (in the default case). This is a weak symbol in the common
 140  * code and thus allows architectures to override it if more needs to be
 141  * done. Not called for suspend to disk.
 142  */
 143 extern void arch_suspend_disable_irqs(void);
 144
 145 /**
 146  * arch_suspend_enable_irqs - enable IRQs after suspend
 147  *
 148  * Enables IRQs (in the default case). This is a weak symbol in the common
 149  * code and thus allows architectures to override it if more needs to be
 150  * done. Not called for suspend to disk.
 151  */
 152 extern void arch_suspend_enable_irqs(void);
 153
 154 extern int pm_suspend(suspend_state_t state);
 155 #else /* !CONFIG_SUSPEND */
 156 #define suspend_valid_only_mem  NULL
 157
 158 static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {}
 159 static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
 160 #endif /* !CONFIG_SUSPEND */
 161
 162 /* struct pbe is used for creating lists of pages that should be restored
 163  * atomically during the resume from disk, because the page frames they have
 164  * occupied before the suspend are in use.
 165  */
 166 struct pbe {
 167         void *address;          /* address of the copy */
 168         void *orig_address;     /* original address of a page */
 169         struct pbe *next;
 170 };
 171
 172 /* mm/page_alloc.c */
 173 extern void mark_free_pages(struct zone *zone);
 174
 175 /**
 176  * struct platform_hibernation_ops - hibernation platform support
 177  *
 178  * The methods in this structure allow a platform to carry out special
 179  * operations required by it during a hibernation transition.
 180  *
 181  * All the methods below, except for @recover(), must be implemented.
 182  *
 183  * @begin: Tell the platform driver that we're starting hibernation.
 184  *      Called right after shrinking memory and before freezing devices.
 185  *
 186  * @end: Called by the PM core right after resuming devices, to indicate to
 187  *      the platform that the system has returned to the working state.
 188  *
 189  * @pre_snapshot: Prepare the platform for creating the hibernation image.
 190  *      Called right after devices have been frozen and before the nonboot
 191  *      CPUs are disabled (runs with IRQs on).
 192  *
 193  * @finish: Restore the previous state of the platform after the hibernation
 194  *      image has been created *or* put the platform into the normal operation
 195  *      mode after the hibernation (the same method is executed in both cases).
 196  *      Called right after the nonboot CPUs have been enabled and before
 197  *      thawing devices (runs with IRQs on).
 198  *
 199  * @prepare: Prepare the platform for entering the low power state.
 200  *      Called right after the hibernation image has been saved and before
 201  *      devices are prepared for entering the low power state.
 202  *
 203  * @enter: Put the system into the low power state after the hibernation image
 204  *      has been saved to disk.
 205  *      Called after the nonboot CPUs have been disabled and all of the low
 206  *      level devices have been shut down (runs with IRQs off).
 207  *
 208  * @leave: Perform the first stage of the cleanup after the system sleep state
 209  *      indicated by @set_target() has been left.
 210  *      Called right after the control has been passed from the boot kernel to
 211  *      the image kernel, before the nonboot CPUs are enabled and before devices
 212  *      are resumed.  Executed with interrupts disabled.
 213  *
 214  * @pre_restore: Prepare system for the restoration from a hibernation image.
 215  *      Called right after devices have been frozen and before the nonboot
 216  *      CPUs are disabled (runs with IRQs on).
 217  *
 218  * @restore_cleanup: Clean up after a failing image restoration.
 219  *      Called right after the nonboot CPUs have been enabled and before
 220  *      thawing devices (runs with IRQs on).
 221  *
 222  * @recover: Recover the platform from a failure to suspend devices.
 223  *      Called by the PM core if the suspending of devices during hibernation
 224  *      fails.  This callback is optional and should only be implemented by
 225  *      platforms which require special recovery actions in that situation.
 226  */
 227 struct platform_hibernation_ops {
 228         int (*begin)(void);
 229         void (*end)(void);
 230         int (*pre_snapshot)(void);
 231         void (*finish)(void);
 232         int (*prepare)(void);
 233         int (*enter)(void);
 234         void (*leave)(void);
 235         int (*pre_restore)(void);
 236         void (*restore_cleanup)(void);
 237         void (*recover)(void);
 238 };
 239
 240 #ifdef CONFIG_HIBERNATION
 241 /* kernel/power/snapshot.c */
 242 extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
 243 static inline void __init register_nosave_region(unsigned long b, unsigned long e)
 244 {
 245         __register_nosave_region(b, e, 0);
 246 }
 247 static inline void __init register_nosave_region_late(unsigned long b, unsigned long e)
 248 {
 249         __register_nosave_region(b, e, 1);
 250 }
 251 extern int swsusp_page_is_forbidden(struct page *);
 252 extern void swsusp_set_page_free(struct page *);
 253 extern void swsusp_unset_page_free(struct page *);
 254 extern unsigned long get_safe_page(gfp_t gfp_mask);
 255
 256 extern void hibernation_set_ops(const struct platform_hibernation_ops *ops);
 257 extern int hibernate(void);
 258 extern bool system_entering_hibernation(void);
 259 #else /* CONFIG_HIBERNATION */
 260 static inline void register_nosave_region(unsigned long b, unsigned long e) {}
 261 static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
 262 static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
 263 static inline void swsusp_set_page_free(struct page *p) {}
 264 static inline void swsusp_unset_page_free(struct page *p) {}
 265
 266 static inline void hibernation_set_ops(const struct platform_hibernation_ops *ops) {}
 267 static inline int hibernate(void) { return -ENOSYS; }
 268 static inline bool system_entering_hibernation(void) { return false; }
 269 #endif /* CONFIG_HIBERNATION */
 270
 271 /* Hibernation and suspend events */
 272 #define PM_HIBERNATION_PREPARE  0x0001 /* Going to hibernate */
 273 #define PM_POST_HIBERNATION     0x0002 /* Hibernation finished */
 274 #define PM_SUSPEND_PREPARE      0x0003 /* Going to suspend the system */
 275 #define PM_POST_SUSPEND         0x0004 /* Suspend finished */
 276 #define PM_RESTORE_PREPARE      0x0005 /* Going to restore a saved image */
 277 #define PM_POST_RESTORE         0x0006 /* Restore failed */
 278
 279 #ifdef CONFIG_PM_SLEEP
 280 void save_processor_state(void);
 281 void restore_processor_state(void);
 282
 283 /* kernel/power/main.c */
 284 extern int register_pm_notifier(struct notifier_block *nb);
 285 extern int unregister_pm_notifier(struct notifier_block *nb);
 286
 287 #define pm_notifier(fn, pri) {                          \
 288         static struct notifier_block fn##_nb =                  \
 289                 { .notifier_call = fn, .priority = pri };       \
 290         register_pm_notifier(&fn##_nb);                 \
 291 }
 292
 293 /* drivers/base/power/wakeup.c */
 294 extern bool events_check_enabled;
 295
 296 extern bool pm_wakeup_pending(void);
 297 extern bool pm_get_wakeup_count(unsigned int *count);
 298 extern bool pm_save_wakeup_count(unsigned int count);
 299 #else /* !CONFIG_PM_SLEEP */
 300
 301 static inline int register_pm_notifier(struct notifier_block *nb)
 302 {
 303         return 0;
 304 }
 305
 306 static inline int unregister_pm_notifier(struct notifier_block *nb)
 307 {
 308         return 0;
 309 }
 310
 311 #define pm_notifier(fn, pri)    do { (void)(fn); } while (0)
 312
 313 static inline bool pm_wakeup_pending(void) { return false; }
 314 #endif /* !CONFIG_PM_SLEEP */
 315
 316 extern struct mutex pm_mutex;
 317
 318 #ifndef CONFIG_HIBERNATE_CALLBACKS
 319 static inline void lock_system_sleep(void) {}
 320 static inline void unlock_system_sleep(void) {}
 321
 322 #else
 323
 324 /* Let some subsystems like memory hotadd exclude hibernation */
 325
 326 static inline void lock_system_sleep(void)
 327 {
 328         mutex_lock(&pm_mutex);
 329 }
 330
 331 static inline void unlock_system_sleep(void)
 332 {
 333         mutex_unlock(&pm_mutex);
 334 }
 335 #endif
 336
 337 #endif /* _LINUX_SUSPEND_H */