/* * Alarmtimer interface * * This interface provides a timer which is similarto hrtimers, * but triggers a RTC alarm if the box is suspend. * * This interface is influenced by the Android RTC Alarm timer * interface. * * Copyright (C) 2010 IBM Corperation * * Author: John Stultz * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "posix-timers.h" #define CREATE_TRACE_POINTS #include /** * struct alarm_base - Alarm timer bases * @lock: Lock for syncrhonized access to the base * @timerqueue: Timerqueue head managing the list of events * @gettime: Function to read the time correlating to the base * @base_clockid: clockid for the base */ static struct alarm_base { spinlock_t lock; struct timerqueue_head timerqueue; ktime_t (*gettime)(void); clockid_t base_clockid; } alarm_bases[ALARM_NUMTYPE]; #if defined(CONFIG_POSIX_TIMERS) || defined(CONFIG_RTC_CLASS) /* freezer information to handle clock_nanosleep triggered wakeups */ static enum alarmtimer_type freezer_alarmtype; static ktime_t freezer_expires; static ktime_t freezer_delta; static DEFINE_SPINLOCK(freezer_delta_lock); #endif #ifdef CONFIG_RTC_CLASS static struct wakeup_source *ws; /* rtc timer and device for setting alarm wakeups at suspend */ static struct rtc_timer rtctimer; static struct rtc_device *rtcdev; static DEFINE_SPINLOCK(rtcdev_lock); static void alarmtimer_triggered_func(void *p) { struct rtc_device *rtc = rtcdev; if (!(rtc->irq_data & RTC_AF)) return; __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); } static struct rtc_task alarmtimer_rtc_task = { .func = alarmtimer_triggered_func }; /** * alarmtimer_get_rtcdev - Return selected rtcdevice * * This function returns the rtc device to use for wakealarms. * If one has not already been chosen, it checks to see if a * functional rtc device is available. */ struct rtc_device *alarmtimer_get_rtcdev(void) { unsigned long flags; struct rtc_device *ret = NULL; spin_lock_irqsave(&rtcdev_lock, flags); ret = rtcdev; spin_unlock_irqrestore(&rtcdev_lock, flags); return ret; } EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); static int alarmtimer_rtc_add_device(struct device *dev, struct class_interface *class_intf) { unsigned long flags; struct rtc_device *rtc = to_rtc_device(dev); struct wakeup_source *__ws; int ret = 0; if (rtcdev) return -EBUSY; if (!rtc->ops->set_alarm) return -1; __ws = wakeup_source_register(dev, "alarmtimer"); spin_lock_irqsave(&rtcdev_lock, flags); if (!rtcdev) { if (!try_module_get(rtc->owner)) { ret = -1; goto unlock; } ret = rtc_irq_register(rtc, &alarmtimer_rtc_task); if (ret) goto unlock; rtcdev = rtc; /* hold a reference so it doesn't go away */ get_device(dev); ws = __ws; __ws = NULL; } unlock: spin_unlock_irqrestore(&rtcdev_lock, flags); wakeup_source_unregister(__ws); return ret; } #ifdef CONFIG_RTC_AUTO_PWRON /* 0|1234|56|78|90|12 */ /* 1|2010|01|01|00|00 */ /*en yyyy mm dd hh mm */ #define BOOTALM_BIT_EN 0 #define BOOTALM_BIT_YEAR 1 #define BOOTALM_BIT_MONTH 5 #define BOOTALM_BIT_DAY 7 #define BOOTALM_BIT_HOUR 9 #define BOOTALM_BIT_MIN 11 #define BOOTALM_BIT_TOTAL 13 int alarm_set_alarm(char *alarm_data) { struct rtc_wkalrm alm; int ret = 0; char buf_ptr[BOOTALM_BIT_TOTAL+1] = {0,}; struct rtc_time rtc_tm; unsigned long rtc_sec; unsigned long rtc_alm_sec; struct timespec delta; struct timespec ktm_ts; struct rtc_time ktm_tm; if (!rtcdev) { printk( "alarm_set_alarm: no RTC, time will be lost on reboot\n"); return -ENXIO; } strlcpy(buf_ptr, alarm_data, BOOTALM_BIT_TOTAL+1); alm.time.tm_sec = 0; alm.time.tm_min = (buf_ptr[BOOTALM_BIT_MIN]-'0') * 10 + (buf_ptr[BOOTALM_BIT_MIN+1]-'0'); alm.time.tm_hour = (buf_ptr[BOOTALM_BIT_HOUR]-'0') * 10 + (buf_ptr[BOOTALM_BIT_HOUR+1]-'0'); alm.time.tm_mday = (buf_ptr[BOOTALM_BIT_DAY]-'0') * 10 + (buf_ptr[BOOTALM_BIT_DAY+1]-'0'); alm.time.tm_mon = (buf_ptr[BOOTALM_BIT_MONTH]-'0') * 10 + (buf_ptr[BOOTALM_BIT_MONTH+1]-'0'); alm.time.tm_year = (buf_ptr[BOOTALM_BIT_YEAR]-'0') * 1000 + (buf_ptr[BOOTALM_BIT_YEAR+1]-'0') * 100 + (buf_ptr[BOOTALM_BIT_YEAR+2]-'0') * 10 + (buf_ptr[BOOTALM_BIT_YEAR+3]-'0'); alm.enabled = (*buf_ptr == '1'); if (*buf_ptr == '2') alm.enabled = 2; pr_info("sapa %s: %s => tm(%d %04d-%02d-%02d %02d:%02d:%02d)\n", __func__, buf_ptr, alm.enabled, alm.time.tm_year, alm.time.tm_mon, alm.time.tm_mday, alm.time.tm_hour, alm.time.tm_min, alm.time.tm_sec); if (alm.enabled) { /* read kernel time */ getnstimeofday(&ktm_ts); ktm_tm = rtc_ktime_to_tm(timespec_to_ktime(ktm_ts)); pr_info("set_sapa: %4d-%02d-%02d %02d:%02d:%02d\n", ktm_tm.tm_year+1900, ktm_tm.tm_mon+1, ktm_tm.tm_mday, ktm_tm.tm_hour, ktm_tm.tm_min, ktm_tm.tm_sec); alm.time.tm_mon -= 1; alm.time.tm_year -= 1900; pr_info("set_sapa: %4d-%02d-%02d %02d:%02d:%02d\n", alm.time.tm_year+1900, alm.time.tm_mon+1, alm.time.tm_mday, alm.time.tm_hour, alm.time.tm_min, alm.time.tm_sec); /* read current time */ rtc_read_time(rtcdev, &rtc_tm); rtc_tm_to_time(&rtc_tm, &rtc_sec); pr_info("set_sapa: %4d-%02d-%02d %02d:%02d:%02d -> %lu\n", rtc_tm.tm_year, rtc_tm.tm_mon, rtc_tm.tm_mday, rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec, rtc_sec); /* calculate offset */ set_normalized_timespec(&delta, ktm_ts.tv_sec - rtc_sec, ktm_ts.tv_nsec); /* convert user requested SAPA time to second type */ rtc_tm_to_time(&alm.time, &rtc_alm_sec); /* convert to RTC time with user requested SAPA time and offset */ rtc_alm_sec -= delta.tv_sec; rtc_alm_sec = (rtc_alm_sec & ~0x00000003) | ((alm.enabled-1)<<1); alm.enabled = 1; rtc_time_to_tm(rtc_alm_sec, &alm.time); pr_info("set_sapa: %4d-%02d-%02d %02d:%02d:%02d -> %lu\n", alm.time.tm_year, alm.time.tm_mon, alm.time.tm_mday, alm.time.tm_hour, alm.time.tm_min, alm.time.tm_sec, rtc_alm_sec); } ret = rtc_set_bootalarm(rtcdev, &alm); if (ret < 0) pr_err("%s: Failed to set bootalarm\n", __func__); return ret; } #endif /*CONFIG_RTC_AUTO_PWRON*/ static void alarmtimer_rtc_remove_device(struct device *dev, struct class_interface *class_intf) { if (rtcdev && dev == &rtcdev->dev) { rtc_irq_unregister(rtcdev, &alarmtimer_rtc_task); rtcdev = NULL; } } static inline void alarmtimer_rtc_timer_init(void) { rtc_timer_init(&rtctimer, NULL, NULL); } static struct class_interface alarmtimer_rtc_interface = { .add_dev = &alarmtimer_rtc_add_device, .remove_dev = &alarmtimer_rtc_remove_device, }; static int alarmtimer_rtc_interface_setup(void) { alarmtimer_rtc_interface.class = rtc_class; return class_interface_register(&alarmtimer_rtc_interface); } static void alarmtimer_rtc_interface_remove(void) { class_interface_unregister(&alarmtimer_rtc_interface); } #else struct rtc_device *alarmtimer_get_rtcdev(void) { return NULL; } #define rtcdev (NULL) static inline int alarmtimer_rtc_interface_setup(void) { return 0; } static inline void alarmtimer_rtc_interface_remove(void) { } static inline void alarmtimer_rtc_timer_init(void) { } #endif /** * alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue * @base: pointer to the base where the timer is being run * @alarm: pointer to alarm being enqueued. * * Adds alarm to a alarm_base timerqueue * * Must hold base->lock when calling. */ static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) { if (alarm->state & ALARMTIMER_STATE_ENQUEUED) timerqueue_del(&base->timerqueue, &alarm->node); timerqueue_add(&base->timerqueue, &alarm->node); alarm->state |= ALARMTIMER_STATE_ENQUEUED; } /** * alarmtimer_dequeue - Removes an alarm timer from an alarm_base timerqueue * @base: pointer to the base where the timer is running * @alarm: pointer to alarm being removed * * Removes alarm to a alarm_base timerqueue * * Must hold base->lock when calling. */ static void alarmtimer_dequeue(struct alarm_base *base, struct alarm *alarm) { if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) return; timerqueue_del(&base->timerqueue, &alarm->node); alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; } /** * alarmtimer_fired - Handles alarm hrtimer being fired. * @timer: pointer to hrtimer being run * * When a alarm timer fires, this runs through the timerqueue to * see which alarms expired, and runs those. If there are more alarm * timers queued for the future, we set the hrtimer to fire when * when the next future alarm timer expires. */ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) { struct alarm *alarm = container_of(timer, struct alarm, timer); struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; int ret = HRTIMER_NORESTART; int restart = ALARMTIMER_NORESTART; spin_lock_irqsave(&base->lock, flags); alarmtimer_dequeue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); if (alarm->function) restart = alarm->function(alarm, base->gettime()); spin_lock_irqsave(&base->lock, flags); if (restart != ALARMTIMER_NORESTART) { hrtimer_set_expires(&alarm->timer, alarm->node.expires); alarmtimer_enqueue(base, alarm); ret = HRTIMER_RESTART; } spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_fired(alarm, base->gettime()); return ret; } ktime_t alarm_expires_remaining(const struct alarm *alarm) { struct alarm_base *base = &alarm_bases[alarm->type]; return ktime_sub(alarm->node.expires, base->gettime()); } EXPORT_SYMBOL_GPL(alarm_expires_remaining); #ifdef CONFIG_RTC_CLASS /** * alarmtimer_suspend - Suspend time callback * @dev: unused * @state: unused * * When we are going into suspend, we look through the bases * to see which is the soonest timer to expire. We then * set an rtc timer to fire that far into the future, which * will wake us from suspend. */ static int alarmtimer_suspend(struct device *dev) { ktime_t min, now, expires; int i, ret, type; struct rtc_device *rtc; unsigned long flags; struct rtc_time tm; #ifdef CONFIG_SEC_PM_DEBUG uint64_t msec = 0; #endif spin_lock_irqsave(&freezer_delta_lock, flags); min = freezer_delta; expires = freezer_expires; type = freezer_alarmtype; freezer_delta = 0; spin_unlock_irqrestore(&freezer_delta_lock, flags); rtc = alarmtimer_get_rtcdev(); /* If we have no rtcdev, just return */ if (!rtc) return 0; /* Find the soonest timer to expire*/ for (i = 0; i < ALARM_NUMTYPE; i++) { struct alarm_base *base = &alarm_bases[i]; struct timerqueue_node *next; ktime_t delta; struct alarm *palarm; spin_lock_irqsave(&base->lock, flags); next = timerqueue_getnext(&base->timerqueue); spin_unlock_irqrestore(&base->lock, flags); if (!next) continue; delta = ktime_sub(next->expires, base->gettime()); palarm = container_of(next, struct alarm, node); pr_info("[%s] cntvct : %lld, gettime : %lld, alarm : %pK,"\ "alarm->function : %pF, expires : %lld, delta : %lld\n", __func__, arch_counter_get_cntvct(), ktime_to_ns(base->gettime()), palarm, palarm->function, ktime_to_ns(next->expires), ktime_to_ns(delta)); if (!min || (delta < min)) { expires = next->expires; min = delta; type = i; } } if (min == 0) return 0; if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) { __pm_wakeup_event(ws, 2 * MSEC_PER_SEC); return -EBUSY; } trace_alarmtimer_suspend(expires, type); /* Setup an rtc timer to fire that far in the future */ rtc_timer_cancel(rtc, &rtctimer); rtc_read_time(rtc, &tm); now = rtc_tm_to_ktime(tm); now = ktime_add(now, min); #ifdef CONFIG_SEC_PM_DEBUG msec = ktime_to_ms(min); pr_info("alarm: will wake up after %llu msecs\n", msec); #endif /* CONFIG_SEC_PM_DEBUG */ /* Set alarm, if in the past reject suspend briefly to handle */ ret = rtc_timer_start(rtc, &rtctimer, now, 0); if (ret < 0) __pm_wakeup_event(ws, MSEC_PER_SEC); return ret; } static int alarmtimer_resume(struct device *dev) { struct rtc_device *rtc; rtc = alarmtimer_get_rtcdev(); if (rtc) rtc_timer_cancel(rtc, &rtctimer); return 0; } #else static int alarmtimer_suspend(struct device *dev) { return 0; } static int alarmtimer_resume(struct device *dev) { return 0; } #endif static void __alarm_init(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) { timerqueue_init(&alarm->node); alarm->timer.function = alarmtimer_fired; alarm->function = function; alarm->type = type; alarm->state = ALARMTIMER_STATE_INACTIVE; } /** * alarm_init - Initialize an alarm structure * @alarm: ptr to alarm to be initialized * @type: the type of the alarm * @function: callback that is run when the alarm fires */ void alarm_init(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) { hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid, HRTIMER_MODE_ABS); __alarm_init(alarm, type, function); } EXPORT_SYMBOL_GPL(alarm_init); /** * alarm_start - Sets an absolute alarm to fire * @alarm: ptr to alarm to set * @start: time to run the alarm */ void alarm_start(struct alarm *alarm, ktime_t start) { struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; spin_lock_irqsave(&base->lock, flags); alarm->node.expires = start; alarmtimer_enqueue(base, alarm); hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS); spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_start(alarm, base->gettime()); } EXPORT_SYMBOL_GPL(alarm_start); /** * alarm_start_relative - Sets a relative alarm to fire * @alarm: ptr to alarm to set * @start: time relative to now to run the alarm */ void alarm_start_relative(struct alarm *alarm, ktime_t start) { struct alarm_base *base = &alarm_bases[alarm->type]; start = ktime_add_safe(start, base->gettime()); alarm_start(alarm, start); } EXPORT_SYMBOL_GPL(alarm_start_relative); void alarm_restart(struct alarm *alarm) { struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; spin_lock_irqsave(&base->lock, flags); hrtimer_set_expires(&alarm->timer, alarm->node.expires); hrtimer_restart(&alarm->timer); alarmtimer_enqueue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); } EXPORT_SYMBOL_GPL(alarm_restart); /** * alarm_try_to_cancel - Tries to cancel an alarm timer * @alarm: ptr to alarm to be canceled * * Returns 1 if the timer was canceled, 0 if it was not running, * and -1 if the callback was running */ int alarm_try_to_cancel(struct alarm *alarm) { struct alarm_base *base = &alarm_bases[alarm->type]; unsigned long flags; int ret; spin_lock_irqsave(&base->lock, flags); ret = hrtimer_try_to_cancel(&alarm->timer); if (ret >= 0) alarmtimer_dequeue(base, alarm); spin_unlock_irqrestore(&base->lock, flags); trace_alarmtimer_cancel(alarm, base->gettime()); return ret; } EXPORT_SYMBOL_GPL(alarm_try_to_cancel); /** * alarm_cancel - Spins trying to cancel an alarm timer until it is done * @alarm: ptr to alarm to be canceled * * Returns 1 if the timer was canceled, 0 if it was not active. */ int alarm_cancel(struct alarm *alarm) { for (;;) { int ret = alarm_try_to_cancel(alarm); if (ret >= 0) return ret; cpu_relax(); } } EXPORT_SYMBOL_GPL(alarm_cancel); u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval) { u64 overrun = 1; ktime_t delta; delta = ktime_sub(now, alarm->node.expires); if (delta < 0) return 0; if (unlikely(delta >= interval)) { s64 incr = ktime_to_ns(interval); overrun = ktime_divns(delta, incr); alarm->node.expires = ktime_add_ns(alarm->node.expires, incr*overrun); if (alarm->node.expires > now) return overrun; /* * This (and the ktime_add() below) is the * correction for exact: */ overrun++; } alarm->node.expires = ktime_add_safe(alarm->node.expires, interval); return overrun; } EXPORT_SYMBOL_GPL(alarm_forward); u64 alarm_forward_now(struct alarm *alarm, ktime_t interval) { struct alarm_base *base = &alarm_bases[alarm->type]; return alarm_forward(alarm, base->gettime(), interval); } EXPORT_SYMBOL_GPL(alarm_forward_now); #ifdef CONFIG_POSIX_TIMERS static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type) { struct alarm_base *base; unsigned long flags; ktime_t delta; switch(type) { case ALARM_REALTIME: base = &alarm_bases[ALARM_REALTIME]; type = ALARM_REALTIME_FREEZER; break; case ALARM_BOOTTIME: base = &alarm_bases[ALARM_BOOTTIME]; type = ALARM_BOOTTIME_FREEZER; break; default: WARN_ONCE(1, "Invalid alarm type: %d\n", type); return; } delta = ktime_sub(absexp, base->gettime()); spin_lock_irqsave(&freezer_delta_lock, flags); if (!freezer_delta || (delta < freezer_delta)) { freezer_delta = delta; freezer_expires = absexp; freezer_alarmtype = type; } spin_unlock_irqrestore(&freezer_delta_lock, flags); } /** * clock2alarm - helper that converts from clockid to alarmtypes * @clockid: clockid. */ static enum alarmtimer_type clock2alarm(clockid_t clockid) { if (clockid == CLOCK_REALTIME_ALARM) return ALARM_REALTIME; if (clockid == CLOCK_BOOTTIME_ALARM) return ALARM_BOOTTIME; return -1; } /** * alarm_handle_timer - Callback for posix timers * @alarm: alarm that fired * * Posix timer callback for expired alarm timers. */ static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, ktime_t now) { struct k_itimer *ptr = container_of(alarm, struct k_itimer, it.alarm.alarmtimer); enum alarmtimer_restart result = ALARMTIMER_NORESTART; unsigned long flags; int si_private = 0; spin_lock_irqsave(&ptr->it_lock, flags); ptr->it_active = 0; if (ptr->it_interval) si_private = ++ptr->it_requeue_pending; if (posix_timer_event(ptr, si_private) && ptr->it_interval) { /* * Handle ignored signals and rearm the timer. This will go * away once we handle ignored signals proper. */ ptr->it_overrun += alarm_forward_now(alarm, ptr->it_interval); ++ptr->it_requeue_pending; ptr->it_active = 1; result = ALARMTIMER_RESTART; } spin_unlock_irqrestore(&ptr->it_lock, flags); return result; } /** * alarm_timer_rearm - Posix timer callback for rearming timer * @timr: Pointer to the posixtimer data struct */ static void alarm_timer_rearm(struct k_itimer *timr) { struct alarm *alarm = &timr->it.alarm.alarmtimer; timr->it_overrun += alarm_forward_now(alarm, timr->it_interval); alarm_start(alarm, alarm->node.expires); } /** * alarm_timer_forward - Posix timer callback for forwarding timer * @timr: Pointer to the posixtimer data struct * @now: Current time to forward the timer against */ static s64 alarm_timer_forward(struct k_itimer *timr, ktime_t now) { struct alarm *alarm = &timr->it.alarm.alarmtimer; return alarm_forward(alarm, timr->it_interval, now); } /** * alarm_timer_remaining - Posix timer callback to retrieve remaining time * @timr: Pointer to the posixtimer data struct * @now: Current time to calculate against */ static ktime_t alarm_timer_remaining(struct k_itimer *timr, ktime_t now) { struct alarm *alarm = &timr->it.alarm.alarmtimer; return ktime_sub(alarm->node.expires, now); } /** * alarm_timer_try_to_cancel - Posix timer callback to cancel a timer * @timr: Pointer to the posixtimer data struct */ static int alarm_timer_try_to_cancel(struct k_itimer *timr) { return alarm_try_to_cancel(&timr->it.alarm.alarmtimer); } /** * alarm_timer_arm - Posix timer callback to arm a timer * @timr: Pointer to the posixtimer data struct * @expires: The new expiry time * @absolute: Expiry value is absolute time * @sigev_none: Posix timer does not deliver signals */ static void alarm_timer_arm(struct k_itimer *timr, ktime_t expires, bool absolute, bool sigev_none) { struct alarm *alarm = &timr->it.alarm.alarmtimer; struct alarm_base *base = &alarm_bases[alarm->type]; if (!absolute) expires = ktime_add_safe(expires, base->gettime()); if (sigev_none) alarm->node.expires = expires; else alarm_start(&timr->it.alarm.alarmtimer, expires); } /** * alarm_clock_getres - posix getres interface * @which_clock: clockid * @tp: timespec to fill * * Returns the granularity of underlying alarm base clock */ static int alarm_clock_getres(const clockid_t which_clock, struct timespec64 *tp) { if (!alarmtimer_get_rtcdev()) return -EINVAL; tp->tv_sec = 0; tp->tv_nsec = hrtimer_resolution; return 0; } /** * alarm_clock_get - posix clock_get interface * @which_clock: clockid * @tp: timespec to fill. * * Provides the underlying alarm base time. */ static int alarm_clock_get(clockid_t which_clock, struct timespec64 *tp) { struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)]; if (!alarmtimer_get_rtcdev()) return -EINVAL; *tp = ktime_to_timespec64(base->gettime()); return 0; } /** * alarm_timer_create - posix timer_create interface * @new_timer: k_itimer pointer to manage * * Initializes the k_itimer structure. */ static int alarm_timer_create(struct k_itimer *new_timer) { enum alarmtimer_type type; if (!alarmtimer_get_rtcdev()) return -EOPNOTSUPP; if (!capable(CAP_WAKE_ALARM)) return -EPERM; type = clock2alarm(new_timer->it_clock); alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer); return 0; } /** * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep * @alarm: ptr to alarm that fired * * Wakes up the task that set the alarmtimer */ static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm, ktime_t now) { struct task_struct *task = (struct task_struct *)alarm->data; alarm->data = NULL; if (task) wake_up_process(task); return ALARMTIMER_NORESTART; } /** * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation * @alarm: ptr to alarmtimer * @absexp: absolute expiration time * * Sets the alarm timer and sleeps until it is fired or interrupted. */ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp, enum alarmtimer_type type) { struct restart_block *restart; alarm->data = (void *)current; do { set_current_state(TASK_INTERRUPTIBLE); alarm_start(alarm, absexp); if (likely(alarm->data)) schedule(); alarm_cancel(alarm); } while (alarm->data && !signal_pending(current)); __set_current_state(TASK_RUNNING); destroy_hrtimer_on_stack(&alarm->timer); if (!alarm->data) return 0; if (freezing(current)) alarmtimer_freezerset(absexp, type); restart = ¤t->restart_block; if (restart->nanosleep.type != TT_NONE) { struct timespec64 rmt; ktime_t rem; rem = ktime_sub(absexp, alarm_bases[type].gettime()); if (rem <= 0) return 0; rmt = ktime_to_timespec64(rem); return nanosleep_copyout(restart, &rmt); } return -ERESTART_RESTARTBLOCK; } static void alarm_init_on_stack(struct alarm *alarm, enum alarmtimer_type type, enum alarmtimer_restart (*function)(struct alarm *, ktime_t)) { hrtimer_init_on_stack(&alarm->timer, alarm_bases[type].base_clockid, HRTIMER_MODE_ABS); __alarm_init(alarm, type, function); } /** * alarm_timer_nsleep_restart - restartblock alarmtimer nsleep * @restart: ptr to restart block * * Handles restarted clock_nanosleep calls */ static long __sched alarm_timer_nsleep_restart(struct restart_block *restart) { enum alarmtimer_type type = restart->nanosleep.clockid; ktime_t exp = restart->nanosleep.expires; struct alarm alarm; alarm_init_on_stack(&alarm, type, alarmtimer_nsleep_wakeup); return alarmtimer_do_nsleep(&alarm, exp, type); } /** * alarm_timer_nsleep - alarmtimer nanosleep * @which_clock: clockid * @flags: determins abstime or relative * @tsreq: requested sleep time (abs or rel) * @rmtp: remaining sleep time saved * * Handles clock_nanosleep calls against _ALARM clockids */ static int alarm_timer_nsleep(const clockid_t which_clock, int flags, const struct timespec64 *tsreq) { enum alarmtimer_type type = clock2alarm(which_clock); struct restart_block *restart = ¤t->restart_block; struct alarm alarm; ktime_t exp; int ret = 0; if (!alarmtimer_get_rtcdev()) return -EOPNOTSUPP; if (flags & ~TIMER_ABSTIME) return -EINVAL; if (!capable(CAP_WAKE_ALARM)) return -EPERM; alarm_init_on_stack(&alarm, type, alarmtimer_nsleep_wakeup); exp = timespec64_to_ktime(*tsreq); /* Convert (if necessary) to absolute time */ if (flags != TIMER_ABSTIME) { ktime_t now = alarm_bases[type].gettime(); exp = ktime_add_safe(now, exp); } ret = alarmtimer_do_nsleep(&alarm, exp, type); if (ret != -ERESTART_RESTARTBLOCK) return ret; /* abs timers don't set remaining time or restart */ if (flags == TIMER_ABSTIME) return -ERESTARTNOHAND; restart->fn = alarm_timer_nsleep_restart; restart->nanosleep.clockid = type; restart->nanosleep.expires = exp; return ret; } const struct k_clock alarm_clock = { .clock_getres = alarm_clock_getres, .clock_get = alarm_clock_get, .timer_create = alarm_timer_create, .timer_set = common_timer_set, .timer_del = common_timer_del, .timer_get = common_timer_get, .timer_arm = alarm_timer_arm, .timer_rearm = alarm_timer_rearm, .timer_forward = alarm_timer_forward, .timer_remaining = alarm_timer_remaining, .timer_try_to_cancel = alarm_timer_try_to_cancel, .nsleep = alarm_timer_nsleep, }; #endif /* CONFIG_POSIX_TIMERS */ /* Suspend hook structures */ static const struct dev_pm_ops alarmtimer_pm_ops = { .suspend = alarmtimer_suspend, .resume = alarmtimer_resume, }; static struct platform_driver alarmtimer_driver = { .driver = { .name = "alarmtimer", .pm = &alarmtimer_pm_ops, } }; /** * alarmtimer_init - Initialize alarm timer code * * This function initializes the alarm bases and registers * the posix clock ids. */ static int __init alarmtimer_init(void) { struct platform_device *pdev; int error = 0; int i; alarmtimer_rtc_timer_init(); /* Initialize alarm bases */ alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME; alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real; alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME; alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime; for (i = 0; i < ALARM_NUMTYPE; i++) { timerqueue_init_head(&alarm_bases[i].timerqueue); spin_lock_init(&alarm_bases[i].lock); } error = alarmtimer_rtc_interface_setup(); if (error) return error; error = platform_driver_register(&alarmtimer_driver); if (error) goto out_if; pdev = platform_device_register_simple("alarmtimer", -1, NULL, 0); if (IS_ERR(pdev)) { error = PTR_ERR(pdev); goto out_drv; } return 0; out_drv: platform_driver_unregister(&alarmtimer_driver); out_if: alarmtimer_rtc_interface_remove(); return error; } device_initcall(alarmtimer_init);