833 lines
20 KiB
C
833 lines
20 KiB
C
/*
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* Alarmtimer interface
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*
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* This interface provides a timer which is similarto hrtimers,
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* but triggers a RTC alarm if the box is suspend.
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*
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* This interface is influenced by the Android RTC Alarm timer
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* interface.
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*
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* Copyright (C) 2010 IBM Corperation
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*
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* Author: John Stultz <john.stultz@linaro.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/time.h>
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#include <linux/hrtimer.h>
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#include <linux/timerqueue.h>
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#include <linux/rtc.h>
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#include <linux/alarmtimer.h>
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#include <linux/mutex.h>
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#include <linux/platform_device.h>
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#include <linux/posix-timers.h>
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#include <linux/workqueue.h>
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#include <linux/freezer.h>
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/**
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* struct alarm_base - Alarm timer bases
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* @lock: Lock for syncrhonized access to the base
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* @timerqueue: Timerqueue head managing the list of events
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* @timer: hrtimer used to schedule events while running
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* @gettime: Function to read the time correlating to the base
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* @base_clockid: clockid for the base
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*/
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static struct alarm_base {
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spinlock_t lock;
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struct timerqueue_head timerqueue;
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struct hrtimer timer;
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ktime_t (*gettime)(void);
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clockid_t base_clockid;
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} alarm_bases[ALARM_NUMTYPE];
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/* freezer delta & lock used to handle clock_nanosleep triggered wakeups */
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static ktime_t freezer_delta;
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static DEFINE_SPINLOCK(freezer_delta_lock);
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#ifdef CONFIG_RTC_CLASS
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/* rtc timer and device for setting alarm wakeups at suspend */
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static struct rtc_timer rtctimer;
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static struct rtc_device *rtcdev;
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static DEFINE_SPINLOCK(rtcdev_lock);
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/**
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* alarmtimer_get_rtcdev - Return selected rtcdevice
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*
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* This function returns the rtc device to use for wakealarms.
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* If one has not already been chosen, it checks to see if a
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* functional rtc device is available.
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*/
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struct rtc_device *alarmtimer_get_rtcdev(void)
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{
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unsigned long flags;
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struct rtc_device *ret;
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spin_lock_irqsave(&rtcdev_lock, flags);
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ret = rtcdev;
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spin_unlock_irqrestore(&rtcdev_lock, flags);
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return ret;
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}
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static int alarmtimer_rtc_add_device(struct device *dev,
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struct class_interface *class_intf)
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{
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unsigned long flags;
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struct rtc_device *rtc = to_rtc_device(dev);
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if (rtcdev)
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return -EBUSY;
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if (!rtc->ops->set_alarm)
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return -1;
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if (!device_may_wakeup(rtc->dev.parent))
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return -1;
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spin_lock_irqsave(&rtcdev_lock, flags);
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if (!rtcdev) {
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rtcdev = rtc;
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/* hold a reference so it doesn't go away */
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get_device(dev);
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}
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spin_unlock_irqrestore(&rtcdev_lock, flags);
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return 0;
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}
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static inline void alarmtimer_rtc_timer_init(void)
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{
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rtc_timer_init(&rtctimer, NULL, NULL);
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}
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static struct class_interface alarmtimer_rtc_interface = {
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.add_dev = &alarmtimer_rtc_add_device,
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};
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static int alarmtimer_rtc_interface_setup(void)
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{
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alarmtimer_rtc_interface.class = rtc_class;
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return class_interface_register(&alarmtimer_rtc_interface);
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}
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static void alarmtimer_rtc_interface_remove(void)
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{
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class_interface_unregister(&alarmtimer_rtc_interface);
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}
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#else
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struct rtc_device *alarmtimer_get_rtcdev(void)
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{
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return NULL;
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}
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#define rtcdev (NULL)
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static inline int alarmtimer_rtc_interface_setup(void) { return 0; }
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static inline void alarmtimer_rtc_interface_remove(void) { }
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static inline void alarmtimer_rtc_timer_init(void) { }
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#endif
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/**
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* alarmtimer_enqueue - Adds an alarm timer to an alarm_base timerqueue
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* @base: pointer to the base where the timer is being run
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* @alarm: pointer to alarm being enqueued.
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*
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* Adds alarm to a alarm_base timerqueue and if necessary sets
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* an hrtimer to run.
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*
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* Must hold base->lock when calling.
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*/
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static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm)
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{
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timerqueue_add(&base->timerqueue, &alarm->node);
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alarm->state |= ALARMTIMER_STATE_ENQUEUED;
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if (&alarm->node == timerqueue_getnext(&base->timerqueue)) {
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hrtimer_try_to_cancel(&base->timer);
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hrtimer_start(&base->timer, alarm->node.expires,
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HRTIMER_MODE_ABS);
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}
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}
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/**
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* alarmtimer_remove - Removes an alarm timer from an alarm_base timerqueue
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* @base: pointer to the base where the timer is running
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* @alarm: pointer to alarm being removed
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*
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* Removes alarm to a alarm_base timerqueue and if necessary sets
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* a new timer to run.
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*
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* Must hold base->lock when calling.
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*/
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static void alarmtimer_remove(struct alarm_base *base, struct alarm *alarm)
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{
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struct timerqueue_node *next = timerqueue_getnext(&base->timerqueue);
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if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED))
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return;
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timerqueue_del(&base->timerqueue, &alarm->node);
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alarm->state &= ~ALARMTIMER_STATE_ENQUEUED;
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if (next == &alarm->node) {
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hrtimer_try_to_cancel(&base->timer);
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next = timerqueue_getnext(&base->timerqueue);
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if (!next)
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return;
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hrtimer_start(&base->timer, next->expires, HRTIMER_MODE_ABS);
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}
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}
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/**
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* alarmtimer_fired - Handles alarm hrtimer being fired.
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* @timer: pointer to hrtimer being run
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*
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* When a alarm timer fires, this runs through the timerqueue to
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* see which alarms expired, and runs those. If there are more alarm
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* timers queued for the future, we set the hrtimer to fire when
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* when the next future alarm timer expires.
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*/
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static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
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{
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struct alarm_base *base = container_of(timer, struct alarm_base, timer);
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struct timerqueue_node *next;
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unsigned long flags;
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ktime_t now;
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int ret = HRTIMER_NORESTART;
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int restart = ALARMTIMER_NORESTART;
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spin_lock_irqsave(&base->lock, flags);
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now = base->gettime();
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while ((next = timerqueue_getnext(&base->timerqueue))) {
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struct alarm *alarm;
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ktime_t expired = next->expires;
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if (expired.tv64 > now.tv64)
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break;
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alarm = container_of(next, struct alarm, node);
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timerqueue_del(&base->timerqueue, &alarm->node);
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alarm->state &= ~ALARMTIMER_STATE_ENQUEUED;
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alarm->state |= ALARMTIMER_STATE_CALLBACK;
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spin_unlock_irqrestore(&base->lock, flags);
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if (alarm->function)
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restart = alarm->function(alarm, now);
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spin_lock_irqsave(&base->lock, flags);
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alarm->state &= ~ALARMTIMER_STATE_CALLBACK;
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if (restart != ALARMTIMER_NORESTART) {
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timerqueue_add(&base->timerqueue, &alarm->node);
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alarm->state |= ALARMTIMER_STATE_ENQUEUED;
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}
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}
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if (next) {
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hrtimer_set_expires(&base->timer, next->expires);
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ret = HRTIMER_RESTART;
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}
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spin_unlock_irqrestore(&base->lock, flags);
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return ret;
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}
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#ifdef CONFIG_RTC_CLASS
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/**
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* alarmtimer_suspend - Suspend time callback
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* @dev: unused
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* @state: unused
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*
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* When we are going into suspend, we look through the bases
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* to see which is the soonest timer to expire. We then
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* set an rtc timer to fire that far into the future, which
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* will wake us from suspend.
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*/
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static int alarmtimer_suspend(struct device *dev)
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{
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struct rtc_time tm;
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ktime_t min, now;
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unsigned long flags;
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struct rtc_device *rtc;
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int i;
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spin_lock_irqsave(&freezer_delta_lock, flags);
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min = freezer_delta;
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freezer_delta = ktime_set(0, 0);
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spin_unlock_irqrestore(&freezer_delta_lock, flags);
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rtc = alarmtimer_get_rtcdev();
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/* If we have no rtcdev, just return */
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if (!rtc)
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return 0;
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/* Find the soonest timer to expire*/
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for (i = 0; i < ALARM_NUMTYPE; i++) {
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struct alarm_base *base = &alarm_bases[i];
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struct timerqueue_node *next;
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ktime_t delta;
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spin_lock_irqsave(&base->lock, flags);
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next = timerqueue_getnext(&base->timerqueue);
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spin_unlock_irqrestore(&base->lock, flags);
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if (!next)
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continue;
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delta = ktime_sub(next->expires, base->gettime());
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if (!min.tv64 || (delta.tv64 < min.tv64))
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min = delta;
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}
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if (min.tv64 == 0)
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return 0;
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/* XXX - Should we enforce a minimum sleep time? */
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WARN_ON(min.tv64 < NSEC_PER_SEC);
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/* Setup an rtc timer to fire that far in the future */
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rtc_timer_cancel(rtc, &rtctimer);
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rtc_read_time(rtc, &tm);
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now = rtc_tm_to_ktime(tm);
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now = ktime_add(now, min);
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rtc_timer_start(rtc, &rtctimer, now, ktime_set(0, 0));
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return 0;
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}
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#else
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static int alarmtimer_suspend(struct device *dev)
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{
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return 0;
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}
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#endif
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static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
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{
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ktime_t delta;
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unsigned long flags;
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struct alarm_base *base = &alarm_bases[type];
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delta = ktime_sub(absexp, base->gettime());
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spin_lock_irqsave(&freezer_delta_lock, flags);
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if (!freezer_delta.tv64 || (delta.tv64 < freezer_delta.tv64))
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freezer_delta = delta;
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spin_unlock_irqrestore(&freezer_delta_lock, flags);
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}
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/**
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* alarm_init - Initialize an alarm structure
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* @alarm: ptr to alarm to be initialized
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* @type: the type of the alarm
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* @function: callback that is run when the alarm fires
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*/
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void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
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enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
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{
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timerqueue_init(&alarm->node);
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alarm->function = function;
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alarm->type = type;
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alarm->state = ALARMTIMER_STATE_INACTIVE;
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}
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/**
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* alarm_start - Sets an alarm to fire
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* @alarm: ptr to alarm to set
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* @start: time to run the alarm
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*/
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void alarm_start(struct alarm *alarm, ktime_t start)
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{
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struct alarm_base *base = &alarm_bases[alarm->type];
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unsigned long flags;
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spin_lock_irqsave(&base->lock, flags);
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if (alarmtimer_active(alarm))
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alarmtimer_remove(base, alarm);
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alarm->node.expires = start;
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alarmtimer_enqueue(base, alarm);
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spin_unlock_irqrestore(&base->lock, flags);
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}
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/**
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* alarm_try_to_cancel - Tries to cancel an alarm timer
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* @alarm: ptr to alarm to be canceled
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*
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* Returns 1 if the timer was canceled, 0 if it was not running,
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* and -1 if the callback was running
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*/
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int alarm_try_to_cancel(struct alarm *alarm)
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{
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struct alarm_base *base = &alarm_bases[alarm->type];
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unsigned long flags;
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int ret = -1;
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spin_lock_irqsave(&base->lock, flags);
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if (alarmtimer_callback_running(alarm))
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goto out;
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if (alarmtimer_is_queued(alarm)) {
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alarmtimer_remove(base, alarm);
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ret = 1;
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} else
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ret = 0;
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out:
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spin_unlock_irqrestore(&base->lock, flags);
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return ret;
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}
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/**
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* alarm_cancel - Spins trying to cancel an alarm timer until it is done
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* @alarm: ptr to alarm to be canceled
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*
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* Returns 1 if the timer was canceled, 0 if it was not active.
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*/
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int alarm_cancel(struct alarm *alarm)
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{
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for (;;) {
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int ret = alarm_try_to_cancel(alarm);
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if (ret >= 0)
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return ret;
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cpu_relax();
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}
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}
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u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval)
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{
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u64 overrun = 1;
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ktime_t delta;
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delta = ktime_sub(now, alarm->node.expires);
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if (delta.tv64 < 0)
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return 0;
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if (unlikely(delta.tv64 >= interval.tv64)) {
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s64 incr = ktime_to_ns(interval);
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overrun = ktime_divns(delta, incr);
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alarm->node.expires = ktime_add_ns(alarm->node.expires,
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incr*overrun);
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if (alarm->node.expires.tv64 > now.tv64)
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return overrun;
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/*
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* This (and the ktime_add() below) is the
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* correction for exact:
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*/
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overrun++;
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}
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alarm->node.expires = ktime_add(alarm->node.expires, interval);
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return overrun;
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}
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/**
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* clock2alarm - helper that converts from clockid to alarmtypes
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* @clockid: clockid.
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*/
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static enum alarmtimer_type clock2alarm(clockid_t clockid)
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{
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if (clockid == CLOCK_REALTIME_ALARM)
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return ALARM_REALTIME;
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if (clockid == CLOCK_BOOTTIME_ALARM)
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return ALARM_BOOTTIME;
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return -1;
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}
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/**
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* alarm_handle_timer - Callback for posix timers
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* @alarm: alarm that fired
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*
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* Posix timer callback for expired alarm timers.
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*/
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static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
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ktime_t now)
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{
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struct k_itimer *ptr = container_of(alarm, struct k_itimer,
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it.alarm.alarmtimer);
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if (posix_timer_event(ptr, 0) != 0)
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ptr->it_overrun++;
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/* Re-add periodic timers */
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if (ptr->it.alarm.interval.tv64) {
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ptr->it_overrun += alarm_forward(alarm, now,
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ptr->it.alarm.interval);
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return ALARMTIMER_RESTART;
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}
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return ALARMTIMER_NORESTART;
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}
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/**
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* alarm_clock_getres - posix getres interface
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* @which_clock: clockid
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* @tp: timespec to fill
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*
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* Returns the granularity of underlying alarm base clock
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*/
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static int alarm_clock_getres(const clockid_t which_clock, struct timespec *tp)
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{
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clockid_t baseid = alarm_bases[clock2alarm(which_clock)].base_clockid;
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if (!alarmtimer_get_rtcdev())
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return -ENOTSUPP;
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return hrtimer_get_res(baseid, tp);
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}
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/**
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* alarm_clock_get - posix clock_get interface
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* @which_clock: clockid
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* @tp: timespec to fill.
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*
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* Provides the underlying alarm base time.
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*/
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static int alarm_clock_get(clockid_t which_clock, struct timespec *tp)
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{
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struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
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if (!alarmtimer_get_rtcdev())
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return -ENOTSUPP;
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*tp = ktime_to_timespec(base->gettime());
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return 0;
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}
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/**
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* alarm_timer_create - posix timer_create interface
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* @new_timer: k_itimer pointer to manage
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*
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* Initializes the k_itimer structure.
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*/
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static int alarm_timer_create(struct k_itimer *new_timer)
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{
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enum alarmtimer_type type;
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struct alarm_base *base;
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if (!alarmtimer_get_rtcdev())
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return -ENOTSUPP;
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if (!capable(CAP_WAKE_ALARM))
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return -EPERM;
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type = clock2alarm(new_timer->it_clock);
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base = &alarm_bases[type];
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alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer);
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return 0;
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}
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/**
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* alarm_timer_get - posix timer_get interface
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* @new_timer: k_itimer pointer
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* @cur_setting: itimerspec data to fill
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*
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* Copies the itimerspec data out from the k_itimer
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*/
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static void alarm_timer_get(struct k_itimer *timr,
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struct itimerspec *cur_setting)
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{
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memset(cur_setting, 0, sizeof(struct itimerspec));
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cur_setting->it_interval =
|
|
ktime_to_timespec(timr->it.alarm.interval);
|
|
cur_setting->it_value =
|
|
ktime_to_timespec(timr->it.alarm.alarmtimer.node.expires);
|
|
return;
|
|
}
|
|
|
|
/**
|
|
* alarm_timer_del - posix timer_del interface
|
|
* @timr: k_itimer pointer to be deleted
|
|
*
|
|
* Cancels any programmed alarms for the given timer.
|
|
*/
|
|
static int alarm_timer_del(struct k_itimer *timr)
|
|
{
|
|
if (!rtcdev)
|
|
return -ENOTSUPP;
|
|
|
|
if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0)
|
|
return TIMER_RETRY;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* alarm_timer_set - posix timer_set interface
|
|
* @timr: k_itimer pointer to be deleted
|
|
* @flags: timer flags
|
|
* @new_setting: itimerspec to be used
|
|
* @old_setting: itimerspec being replaced
|
|
*
|
|
* Sets the timer to new_setting, and starts the timer.
|
|
*/
|
|
static int alarm_timer_set(struct k_itimer *timr, int flags,
|
|
struct itimerspec *new_setting,
|
|
struct itimerspec *old_setting)
|
|
{
|
|
if (!rtcdev)
|
|
return -ENOTSUPP;
|
|
|
|
if (old_setting)
|
|
alarm_timer_get(timr, old_setting);
|
|
|
|
/* If the timer was already set, cancel it */
|
|
if (alarm_try_to_cancel(&timr->it.alarm.alarmtimer) < 0)
|
|
return TIMER_RETRY;
|
|
|
|
/* start the timer */
|
|
timr->it.alarm.interval = timespec_to_ktime(new_setting->it_interval);
|
|
alarm_start(&timr->it.alarm.alarmtimer,
|
|
timespec_to_ktime(new_setting->it_value));
|
|
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)
|
|
{
|
|
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);
|
|
|
|
return (alarm->data == NULL);
|
|
}
|
|
|
|
|
|
/**
|
|
* update_rmtp - Update remaining timespec value
|
|
* @exp: expiration time
|
|
* @type: timer type
|
|
* @rmtp: user pointer to remaining timepsec value
|
|
*
|
|
* Helper function that fills in rmtp value with time between
|
|
* now and the exp value
|
|
*/
|
|
static int update_rmtp(ktime_t exp, enum alarmtimer_type type,
|
|
struct timespec __user *rmtp)
|
|
{
|
|
struct timespec rmt;
|
|
ktime_t rem;
|
|
|
|
rem = ktime_sub(exp, alarm_bases[type].gettime());
|
|
|
|
if (rem.tv64 <= 0)
|
|
return 0;
|
|
rmt = ktime_to_timespec(rem);
|
|
|
|
if (copy_to_user(rmtp, &rmt, sizeof(*rmtp)))
|
|
return -EFAULT;
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
struct timespec __user *rmtp;
|
|
struct alarm alarm;
|
|
int ret = 0;
|
|
|
|
exp.tv64 = restart->nanosleep.expires;
|
|
alarm_init(&alarm, type, alarmtimer_nsleep_wakeup);
|
|
|
|
if (alarmtimer_do_nsleep(&alarm, exp))
|
|
goto out;
|
|
|
|
if (freezing(current))
|
|
alarmtimer_freezerset(exp, type);
|
|
|
|
rmtp = restart->nanosleep.rmtp;
|
|
if (rmtp) {
|
|
ret = update_rmtp(exp, type, rmtp);
|
|
if (ret <= 0)
|
|
goto out;
|
|
}
|
|
|
|
|
|
/* The other values in restart are already filled in */
|
|
ret = -ERESTART_RESTARTBLOCK;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* 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,
|
|
struct timespec *tsreq, struct timespec __user *rmtp)
|
|
{
|
|
enum alarmtimer_type type = clock2alarm(which_clock);
|
|
struct alarm alarm;
|
|
ktime_t exp;
|
|
int ret = 0;
|
|
struct restart_block *restart;
|
|
|
|
if (!alarmtimer_get_rtcdev())
|
|
return -ENOTSUPP;
|
|
|
|
if (!capable(CAP_WAKE_ALARM))
|
|
return -EPERM;
|
|
|
|
alarm_init(&alarm, type, alarmtimer_nsleep_wakeup);
|
|
|
|
exp = timespec_to_ktime(*tsreq);
|
|
/* Convert (if necessary) to absolute time */
|
|
if (flags != TIMER_ABSTIME) {
|
|
ktime_t now = alarm_bases[type].gettime();
|
|
exp = ktime_add(now, exp);
|
|
}
|
|
|
|
if (alarmtimer_do_nsleep(&alarm, exp))
|
|
goto out;
|
|
|
|
if (freezing(current))
|
|
alarmtimer_freezerset(exp, type);
|
|
|
|
/* abs timers don't set remaining time or restart */
|
|
if (flags == TIMER_ABSTIME) {
|
|
ret = -ERESTARTNOHAND;
|
|
goto out;
|
|
}
|
|
|
|
if (rmtp) {
|
|
ret = update_rmtp(exp, type, rmtp);
|
|
if (ret <= 0)
|
|
goto out;
|
|
}
|
|
|
|
restart = ¤t_thread_info()->restart_block;
|
|
restart->fn = alarm_timer_nsleep_restart;
|
|
restart->nanosleep.clockid = type;
|
|
restart->nanosleep.expires = exp.tv64;
|
|
restart->nanosleep.rmtp = rmtp;
|
|
ret = -ERESTART_RESTARTBLOCK;
|
|
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
|
|
/* Suspend hook structures */
|
|
static const struct dev_pm_ops alarmtimer_pm_ops = {
|
|
.suspend = alarmtimer_suspend,
|
|
};
|
|
|
|
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;
|
|
struct k_clock alarm_clock = {
|
|
.clock_getres = alarm_clock_getres,
|
|
.clock_get = alarm_clock_get,
|
|
.timer_create = alarm_timer_create,
|
|
.timer_set = alarm_timer_set,
|
|
.timer_del = alarm_timer_del,
|
|
.timer_get = alarm_timer_get,
|
|
.nsleep = alarm_timer_nsleep,
|
|
};
|
|
|
|
alarmtimer_rtc_timer_init();
|
|
|
|
posix_timers_register_clock(CLOCK_REALTIME_ALARM, &alarm_clock);
|
|
posix_timers_register_clock(CLOCK_BOOTTIME_ALARM, &alarm_clock);
|
|
|
|
/* 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);
|
|
hrtimer_init(&alarm_bases[i].timer,
|
|
alarm_bases[i].base_clockid,
|
|
HRTIMER_MODE_ABS);
|
|
alarm_bases[i].timer.function = alarmtimer_fired;
|
|
}
|
|
|
|
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);
|