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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
14extern void pm_set_vt_switch(int);
15#else
16static inline void pm_set_vt_switch(int do_switch)
17{
18}
19#endif
20
21#ifdef CONFIG_VT_CONSOLE_SLEEP
22extern void pm_prepare_console(void);
23extern void pm_restore_console(void);
24#else
25static inline void pm_prepare_console(void)
26{
27}
28
29static inline void pm_restore_console(void)
30{
31}
32#endif
33
34typedef 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
43enum 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
54struct 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
74extern struct suspend_stats suspend_stats;
75
76static 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
85static 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
92static 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 */
177struct 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
190struct 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
200extern suspend_state_t mem_sleep_current;
201extern 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 */
207extern void suspend_set_ops(const struct platform_suspend_ops *ops);
208extern int suspend_valid_only_mem(suspend_state_t state);
209
210extern 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
215static inline void pm_suspend_clear_flags(void)
216{
217 pm_suspend_global_flags = 0;
218}
219
220static inline void pm_set_suspend_via_firmware(void)
221{
222 pm_suspend_global_flags |= PM_SUSPEND_FLAG_FW_SUSPEND;
223}
224
225static inline void pm_set_resume_via_firmware(void)
226{
227 pm_suspend_global_flags |= PM_SUSPEND_FLAG_FW_RESUME;
228}
229
230static inline bool pm_suspend_via_firmware(void)
231{
232 return !!(pm_suspend_global_flags & PM_SUSPEND_FLAG_FW_SUSPEND);
233}
234
235static 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. */
241enum 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
247extern enum s2idle_states __read_mostly s2idle_state;
248
249static inline bool idle_should_enter_s2idle(void)
250{
251 return unlikely(s2idle_state == S2IDLE_STATE_ENTER);
252}
253
254extern void __init pm_states_init(void);
255extern void s2idle_set_ops(const struct platform_s2idle_ops *ops);
256extern void s2idle_wake(void);
257
258/**
259 * arch_suspend_disable_irqs - disable IRQs for suspend
260 *
261 * Disables IRQs (in the default case). This is a weak symbol in the common
262 * code and thus allows architectures to override it if more needs to be
263 * done. Not called for suspend to disk.
264 */
265extern void arch_suspend_disable_irqs(void);
266
267/**
268 * arch_suspend_enable_irqs - enable IRQs after suspend
269 *
270 * Enables IRQs (in the default case). This is a weak symbol in the common
271 * code and thus allows architectures to override it if more needs to be
272 * done. Not called for suspend to disk.
273 */
274extern void arch_suspend_enable_irqs(void);
275
276extern int pm_suspend(suspend_state_t state);
277#else /* !CONFIG_SUSPEND */
278#define suspend_valid_only_mem NULL
279
280static inline void pm_suspend_clear_flags(void) {}
281static inline void pm_set_suspend_via_firmware(void) {}
282static inline void pm_set_resume_via_firmware(void) {}
283static inline bool pm_suspend_via_firmware(void) { return false; }
284static inline bool pm_resume_via_firmware(void) { return false; }
285
286static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {}
287static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
288static inline bool idle_should_enter_s2idle(void) { return false; }
289static inline void __init pm_states_init(void) {}
290static inline void s2idle_set_ops(const struct platform_s2idle_ops *ops) {}
291static inline void s2idle_wake(void) {}
292#endif /* !CONFIG_SUSPEND */
293
294/* struct pbe is used for creating lists of pages that should be restored
295 * atomically during the resume from disk, because the page frames they have
296 * occupied before the suspend are in use.
297 */
298struct pbe {
299 void *address; /* address of the copy */
300 void *orig_address; /* original address of a page */
301 struct pbe *next;
302};
303
304/* mm/page_alloc.c */
305extern void mark_free_pages(struct zone *zone);
306
307/**
308 * struct platform_hibernation_ops - hibernation platform support
309 *
310 * The methods in this structure allow a platform to carry out special
311 * operations required by it during a hibernation transition.
312 *
313 * All the methods below, except for @recover(), must be implemented.
314 *
315 * @begin: Tell the platform driver that we're starting hibernation.
316 * Called right after shrinking memory and before freezing devices.
317 *
318 * @end: Called by the PM core right after resuming devices, to indicate to
319 * the platform that the system has returned to the working state.
320 *
321 * @pre_snapshot: Prepare the platform for creating the hibernation image.
322 * Called right after devices have been frozen and before the nonboot
323 * CPUs are disabled (runs with IRQs on).
324 *
325 * @finish: Restore the previous state of the platform after the hibernation
326 * image has been created *or* put the platform into the normal operation
327 * mode after the hibernation (the same method is executed in both cases).
328 * Called right after the nonboot CPUs have been enabled and before
329 * thawing devices (runs with IRQs on).
330 *
331 * @prepare: Prepare the platform for entering the low power state.
332 * Called right after the hibernation image has been saved and before
333 * devices are prepared for entering the low power state.
334 *
335 * @enter: Put the system into the low power state after the hibernation image
336 * has been saved to disk.
337 * Called after the nonboot CPUs have been disabled and all of the low
338 * level devices have been shut down (runs with IRQs off).
339 *
340 * @leave: Perform the first stage of the cleanup after the system sleep state
341 * indicated by @set_target() has been left.
342 * Called right after the control has been passed from the boot kernel to
343 * the image kernel, before the nonboot CPUs are enabled and before devices
344 * are resumed. Executed with interrupts disabled.
345 *
346 * @pre_restore: Prepare system for the restoration from a hibernation image.
347 * Called right after devices have been frozen and before the nonboot
348 * CPUs are disabled (runs with IRQs on).
349 *
350 * @restore_cleanup: Clean up after a failing image restoration.
351 * Called right after the nonboot CPUs have been enabled and before
352 * thawing devices (runs with IRQs on).
353 *
354 * @recover: Recover the platform from a failure to suspend devices.
355 * Called by the PM core if the suspending of devices during hibernation
356 * fails. This callback is optional and should only be implemented by
357 * platforms which require special recovery actions in that situation.
358 */
359struct platform_hibernation_ops {
360 int (*begin)(void);
361 void (*end)(void);
362 int (*pre_snapshot)(void);
363 void (*finish)(void);
364 int (*prepare)(void);
365 int (*enter)(void);
366 void (*leave)(void);
367 int (*pre_restore)(void);
368 void (*restore_cleanup)(void);
369 void (*recover)(void);
370};
371
372#ifdef CONFIG_HIBERNATION
373/* kernel/power/snapshot.c */
374extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
375static inline void __init register_nosave_region(unsigned long b, unsigned long e)
376{
377 __register_nosave_region(b, e, 0);
378}
379static inline void __init register_nosave_region_late(unsigned long b, unsigned long e)
380{
381 __register_nosave_region(b, e, 1);
382}
383extern int swsusp_page_is_forbidden(struct page *);
384extern void swsusp_set_page_free(struct page *);
385extern void swsusp_unset_page_free(struct page *);
386extern unsigned long get_safe_page(gfp_t gfp_mask);
387
388extern void hibernation_set_ops(const struct platform_hibernation_ops *ops);
389extern int hibernate(void);
390extern bool system_entering_hibernation(void);
391extern bool hibernation_available(void);
392asmlinkage int swsusp_save(void);
393extern struct pbe *restore_pblist;
394#else /* CONFIG_HIBERNATION */
395static inline void register_nosave_region(unsigned long b, unsigned long e) {}
396static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
397static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
398static inline void swsusp_set_page_free(struct page *p) {}
399static inline void swsusp_unset_page_free(struct page *p) {}
400
401static inline void hibernation_set_ops(const struct platform_hibernation_ops *ops) {}
402static inline int hibernate(void) { return -ENOSYS; }
403static inline bool system_entering_hibernation(void) { return false; }
404static inline bool hibernation_available(void) { return false; }
405#endif /* CONFIG_HIBERNATION */
406
407/* Hibernation and suspend events */
408#define PM_HIBERNATION_PREPARE 0x0001 /* Going to hibernate */
409#define PM_POST_HIBERNATION 0x0002 /* Hibernation finished */
410#define PM_SUSPEND_PREPARE 0x0003 /* Going to suspend the system */
411#define PM_POST_SUSPEND 0x0004 /* Suspend finished */
412#define PM_RESTORE_PREPARE 0x0005 /* Going to restore a saved image */
413#define PM_POST_RESTORE 0x0006 /* Restore failed */
414
415extern struct mutex pm_mutex;
416
417#ifdef CONFIG_PM_SLEEP
418void save_processor_state(void);
419void restore_processor_state(void);
420
421/* kernel/power/main.c */
422extern int register_pm_notifier(struct notifier_block *nb);
423extern int unregister_pm_notifier(struct notifier_block *nb);
424
425#define pm_notifier(fn, pri) { \
426 static struct notifier_block fn##_nb = \
427 { .notifier_call = fn, .priority = pri }; \
428 register_pm_notifier(&fn##_nb); \
429}
430
431/* drivers/base/power/wakeup.c */
432extern bool events_check_enabled;
433extern unsigned int pm_wakeup_irq;
434extern suspend_state_t pm_suspend_target_state;
435
436extern bool pm_wakeup_pending(void);
437extern void pm_system_wakeup(void);
438extern void pm_system_cancel_wakeup(void);
439extern void pm_wakeup_clear(bool reset);
440extern void pm_system_irq_wakeup(unsigned int irq_number);
441extern bool pm_get_wakeup_count(unsigned int *count, bool block);
442extern bool pm_save_wakeup_count(unsigned int count);
443extern void pm_wakep_autosleep_enabled(bool set);
444extern void pm_print_active_wakeup_sources(void);
445
446static inline void lock_system_sleep(void)
447{
448 current->flags |= PF_FREEZER_SKIP;
449 mutex_lock(&pm_mutex);
450}
451
452static inline void unlock_system_sleep(void)
453{
454 /*
455 * Don't use freezer_count() because we don't want the call to
456 * try_to_freeze() here.
457 *
458 * Reason:
459 * Fundamentally, we just don't need it, because freezing condition
460 * doesn't come into effect until we release the pm_mutex lock,
461 * since the freezer always works with pm_mutex held.
462 *
463 * More importantly, in the case of hibernation,
464 * unlock_system_sleep() gets called in snapshot_read() and
465 * snapshot_write() when the freezing condition is still in effect.
466 * Which means, if we use try_to_freeze() here, it would make them
467 * enter the refrigerator, thus causing hibernation to lockup.
468 */
469 current->flags &= ~PF_FREEZER_SKIP;
470 mutex_unlock(&pm_mutex);
471}
472
473#else /* !CONFIG_PM_SLEEP */
474
475static inline int register_pm_notifier(struct notifier_block *nb)
476{
477 return 0;
478}
479
480static inline int unregister_pm_notifier(struct notifier_block *nb)
481{
482 return 0;
483}
484
485#define pm_notifier(fn, pri) do { (void)(fn); } while (0)
486
487static inline bool pm_wakeup_pending(void) { return false; }
488static inline void pm_system_wakeup(void) {}
489static inline void pm_wakeup_clear(bool reset) {}
490static inline void pm_system_irq_wakeup(unsigned int irq_number) {}
491
492static inline void lock_system_sleep(void) {}
493static inline void unlock_system_sleep(void) {}
494
495#endif /* !CONFIG_PM_SLEEP */
496
497#ifdef CONFIG_PM_SLEEP_DEBUG
498extern bool pm_print_times_enabled;
499extern bool pm_debug_messages_on;
500extern __printf(2, 3) void __pm_pr_dbg(bool defer, const char *fmt, ...);
501#else
502#define pm_print_times_enabled (false)
503#define pm_debug_messages_on (false)
504
505#include <linux/printk.h>
506
507#define __pm_pr_dbg(defer, fmt, ...) \
508 no_printk(KERN_DEBUG fmt, ##__VA_ARGS__)
509#endif
510
511#define pm_pr_dbg(fmt, ...) \
512 __pm_pr_dbg(false, fmt, ##__VA_ARGS__)
513
514#define pm_deferred_pr_dbg(fmt, ...) \
515 __pm_pr_dbg(true, fmt, ##__VA_ARGS__)
516
517#ifdef CONFIG_PM_AUTOSLEEP
518
519/* kernel/power/autosleep.c */
520void queue_up_suspend_work(void);
521
522#else /* !CONFIG_PM_AUTOSLEEP */
523
524static inline void queue_up_suspend_work(void) {}
525
526#endif /* !CONFIG_PM_AUTOSLEEP */
527
528#ifdef CONFIG_ARCH_SAVE_PAGE_KEYS
529/*
530 * The ARCH_SAVE_PAGE_KEYS functions can be used by an architecture
531 * to save/restore additional information to/from the array of page
532 * frame numbers in the hibernation image. For s390 this is used to
533 * save and restore the storage key for each page that is included
534 * in the hibernation image.
535 */
536unsigned long page_key_additional_pages(unsigned long pages);
537int page_key_alloc(unsigned long pages);
538void page_key_free(void);
539void page_key_read(unsigned long *pfn);
540void page_key_memorize(unsigned long *pfn);
541void page_key_write(void *address);
542
543#else /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
544
545static inline unsigned long page_key_additional_pages(unsigned long pages)
546{
547 return 0;
548}
549
550static inline int page_key_alloc(unsigned long pages)
551{
552 return 0;
553}
554
555static inline void page_key_free(void) {}
556static inline void page_key_read(unsigned long *pfn) {}
557static inline void page_key_memorize(unsigned long *pfn) {}
558static inline void page_key_write(void *address) {}
559
560#endif /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
561
562#endif /* _LINUX_SUSPEND_H */