^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * kernel/power/autosleep.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Opportunistic sleep support.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * Copyright (C) 2012 Rafael J. Wysocki <rjw@sisk.pl>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/mutex.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/pm_wakeup.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include "power.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) static suspend_state_t autosleep_state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) static struct workqueue_struct *autosleep_wq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * Note: it is only safe to mutex_lock(&autosleep_lock) if a wakeup_source
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * is active, otherwise a deadlock with try_to_suspend() is possible.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * Alternatively mutex_lock_interruptible() can be used. This will then fail
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * if an auto_sleep cycle tries to freeze processes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) static DEFINE_MUTEX(autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static struct wakeup_source *autosleep_ws;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) static void try_to_suspend(struct work_struct *work)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) unsigned int initial_count, final_count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) if (!pm_get_wakeup_count(&initial_count, true))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) mutex_lock(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) if (!pm_save_wakeup_count(initial_count) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) system_state != SYSTEM_RUNNING) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) mutex_unlock(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) if (autosleep_state == PM_SUSPEND_ON) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) mutex_unlock(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) if (autosleep_state >= PM_SUSPEND_MAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) hibernate();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) pm_suspend(autosleep_state);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) mutex_unlock(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) if (!pm_get_wakeup_count(&final_count, false))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * If the wakeup occured for an unknown reason, wait to prevent the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) * system from trying to suspend and waking up in a tight loop.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) if (final_count == initial_count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) schedule_timeout_uninterruptible(HZ / 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) queue_up_suspend_work();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) static DECLARE_WORK(suspend_work, try_to_suspend);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) void queue_up_suspend_work(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) if (autosleep_state > PM_SUSPEND_ON)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) queue_work(autosleep_wq, &suspend_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) suspend_state_t pm_autosleep_state(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) return autosleep_state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) int pm_autosleep_lock(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) return mutex_lock_interruptible(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) void pm_autosleep_unlock(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) mutex_unlock(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) int pm_autosleep_set_state(suspend_state_t state)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) #ifndef CONFIG_HIBERNATION
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) if (state >= PM_SUSPEND_MAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) __pm_stay_awake(autosleep_ws);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) mutex_lock(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) autosleep_state = state;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) __pm_relax(autosleep_ws);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) if (state > PM_SUSPEND_ON) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) pm_wakep_autosleep_enabled(true);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) queue_up_suspend_work();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) pm_wakep_autosleep_enabled(false);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) mutex_unlock(&autosleep_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) int __init pm_autosleep_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) autosleep_ws = wakeup_source_register(NULL, "autosleep");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) if (!autosleep_ws)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) autosleep_wq = alloc_ordered_workqueue("autosleep", 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) if (autosleep_wq)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) wakeup_source_unregister(autosleep_ws);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) }