// SPDX-License-Identifier: GPL-2.0
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/*
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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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#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/sched/signal.h>
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#include <linux/sched/debug.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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#include <linux/compat.h>
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#include <linux/module.h>
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#include <linux/time_namespace.h>
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#include "posix-timers.h"
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#define CREATE_TRACE_POINTS
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#include <trace/events/alarmtimer.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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* @get_ktime: Function to read the time correlating to the base
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* @get_timespec: Function to read the namespace 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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ktime_t (*get_ktime)(void);
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void (*get_timespec)(struct timespec64 *tp);
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clockid_t base_clockid;
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} alarm_bases[ALARM_NUMTYPE];
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#if defined(CONFIG_POSIX_TIMERS) || defined(CONFIG_RTC_CLASS)
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/* freezer information to handle clock_nanosleep triggered wakeups */
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static enum alarmtimer_type freezer_alarmtype;
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static ktime_t freezer_expires;
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static ktime_t freezer_delta;
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static DEFINE_SPINLOCK(freezer_delta_lock);
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#endif
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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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*/
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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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EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev);
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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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struct platform_device *pdev;
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int ret = 0;
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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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pdev = platform_device_register_data(dev, "alarmtimer",
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PLATFORM_DEVID_AUTO, NULL, 0);
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if (!IS_ERR(pdev))
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device_init_wakeup(&pdev->dev, true);
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spin_lock_irqsave(&rtcdev_lock, flags);
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if (!IS_ERR(pdev) && !rtcdev) {
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if (!try_module_get(rtc->owner)) {
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ret = -1;
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goto unlock;
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}
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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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pdev = NULL;
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} else {
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ret = -1;
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}
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unlock:
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spin_unlock_irqrestore(&rtcdev_lock, flags);
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platform_device_unregister(pdev);
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return ret;
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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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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
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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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if (alarm->state & ALARMTIMER_STATE_ENQUEUED)
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timerqueue_del(&base->timerqueue, &alarm->node);
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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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* alarmtimer_dequeue - 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
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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_dequeue(struct alarm_base *base, struct alarm *alarm)
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{
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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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}
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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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* 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 *alarm = container_of(timer, struct alarm, timer);
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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 = HRTIMER_NORESTART;
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int restart = ALARMTIMER_NORESTART;
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spin_lock_irqsave(&base->lock, flags);
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alarmtimer_dequeue(base, alarm);
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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, base->get_ktime());
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spin_lock_irqsave(&base->lock, flags);
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if (restart != ALARMTIMER_NORESTART) {
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hrtimer_set_expires(&alarm->timer, alarm->node.expires);
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alarmtimer_enqueue(base, alarm);
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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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trace_alarmtimer_fired(alarm, base->get_ktime());
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return ret;
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}
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ktime_t alarm_expires_remaining(const struct alarm *alarm)
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{
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struct alarm_base *base = &alarm_bases[alarm->type];
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return ktime_sub(alarm->node.expires, base->get_ktime());
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}
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EXPORT_SYMBOL_GPL(alarm_expires_remaining);
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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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*
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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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ktime_t min, now, expires;
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int i, ret, type;
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struct rtc_device *rtc;
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unsigned long flags;
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struct rtc_time tm;
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spin_lock_irqsave(&freezer_delta_lock, flags);
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min = freezer_delta;
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expires = freezer_expires;
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type = freezer_alarmtype;
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freezer_delta = 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->get_ktime());
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if (!min || (delta < min)) {
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expires = next->expires;
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min = delta;
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type = i;
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}
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}
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if (min == 0)
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return 0;
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if (ktime_to_ns(min) < 2 * NSEC_PER_SEC) {
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pm_wakeup_event(dev, 2 * MSEC_PER_SEC);
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return -EBUSY;
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}
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trace_alarmtimer_suspend(expires, type);
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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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/* Set alarm, if in the past reject suspend briefly to handle */
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ret = rtc_timer_start(rtc, &rtctimer, now, 0);
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if (ret < 0)
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pm_wakeup_event(dev, MSEC_PER_SEC);
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return ret;
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}
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static int alarmtimer_resume(struct device *dev)
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{
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struct rtc_device *rtc;
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rtc = alarmtimer_get_rtcdev();
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if (rtc)
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rtc_timer_cancel(rtc, &rtctimer);
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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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static int alarmtimer_resume(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
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__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->timer.function = alarmtimer_fired;
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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_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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hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid,
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HRTIMER_MODE_ABS);
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__alarm_init(alarm, type, function);
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}
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EXPORT_SYMBOL_GPL(alarm_init);
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/**
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* alarm_start - Sets an absolute 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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alarm->node.expires = start;
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alarmtimer_enqueue(base, alarm);
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hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS);
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spin_unlock_irqrestore(&base->lock, flags);
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trace_alarmtimer_start(alarm, base->get_ktime());
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}
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EXPORT_SYMBOL_GPL(alarm_start);
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/**
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* alarm_start_relative - Sets a relative alarm to fire
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* @alarm: ptr to alarm to set
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* @start: time relative to now to run the alarm
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*/
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void alarm_start_relative(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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start = ktime_add_safe(start, base->get_ktime());
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alarm_start(alarm, start);
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}
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EXPORT_SYMBOL_GPL(alarm_start_relative);
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void alarm_restart(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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spin_lock_irqsave(&base->lock, flags);
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hrtimer_set_expires(&alarm->timer, alarm->node.expires);
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hrtimer_restart(&alarm->timer);
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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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EXPORT_SYMBOL_GPL(alarm_restart);
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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;
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spin_lock_irqsave(&base->lock, flags);
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ret = hrtimer_try_to_cancel(&alarm->timer);
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if (ret >= 0)
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alarmtimer_dequeue(base, alarm);
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spin_unlock_irqrestore(&base->lock, flags);
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trace_alarmtimer_cancel(alarm, base->get_ktime());
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return ret;
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}
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EXPORT_SYMBOL_GPL(alarm_try_to_cancel);
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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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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);
|
if (ret >= 0)
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return ret;
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hrtimer_cancel_wait_running(&alarm->timer);
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}
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}
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EXPORT_SYMBOL_GPL(alarm_cancel);
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|
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u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval)
|
{
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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 < 0)
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return 0;
|
|
if (unlikely(delta >= interval)) {
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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 > now)
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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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overrun++;
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}
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alarm->node.expires = ktime_add_safe(alarm->node.expires, interval);
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return overrun;
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}
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EXPORT_SYMBOL_GPL(alarm_forward);
|
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u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
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{
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struct alarm_base *base = &alarm_bases[alarm->type];
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return alarm_forward(alarm, base->get_ktime(), interval);
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}
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EXPORT_SYMBOL_GPL(alarm_forward_now);
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#ifdef CONFIG_POSIX_TIMERS
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static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
|
{
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struct alarm_base *base;
|
unsigned long flags;
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ktime_t delta;
|
|
switch(type) {
|
case ALARM_REALTIME:
|
base = &alarm_bases[ALARM_REALTIME];
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type = ALARM_REALTIME_FREEZER;
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break;
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case ALARM_BOOTTIME:
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base = &alarm_bases[ALARM_BOOTTIME];
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type = ALARM_BOOTTIME_FREEZER;
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break;
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default:
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WARN_ONCE(1, "Invalid alarm type: %d\n", type);
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return;
|
}
|
|
delta = ktime_sub(absexp, base->get_ktime());
|
|
spin_lock_irqsave(&freezer_delta_lock, flags);
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if (!freezer_delta || (delta < freezer_delta)) {
|
freezer_delta = delta;
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freezer_expires = absexp;
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freezer_alarmtype = type;
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}
|
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)
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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_wait_running - Posix timer callback to wait for a timer
|
* @timr: Pointer to the posixtimer data struct
|
*
|
* Called from the core code when timer cancel detected that the callback
|
* is running. @timr is unlocked and rcu read lock is held to prevent it
|
* from being freed.
|
*/
|
static void alarm_timer_wait_running(struct k_itimer *timr)
|
{
|
hrtimer_cancel_wait_running(&timr->it.alarm.alarmtimer.timer);
|
}
|
|
/**
|
* 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->get_ktime());
|
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_timespec - posix clock_get_timespec interface
|
* @which_clock: clockid
|
* @tp: timespec to fill.
|
*
|
* Provides the underlying alarm base time in a tasks time namespace.
|
*/
|
static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp)
|
{
|
struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
|
|
if (!alarmtimer_get_rtcdev())
|
return -EINVAL;
|
|
base->get_timespec(tp);
|
|
return 0;
|
}
|
|
/**
|
* alarm_clock_get_ktime - posix clock_get_ktime interface
|
* @which_clock: clockid
|
*
|
* Provides the underlying alarm base time in the root namespace.
|
*/
|
static ktime_t alarm_clock_get_ktime(clockid_t which_clock)
|
{
|
struct alarm_base *base = &alarm_bases[clock2alarm(which_clock)];
|
|
if (!alarmtimer_get_rtcdev())
|
return -EINVAL;
|
|
return base->get_ktime();
|
}
|
|
/**
|
* 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].get_ktime());
|
|
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].get_ktime();
|
|
exp = ktime_add_safe(now, exp);
|
} else {
|
exp = timens_ktime_to_host(which_clock, 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->nanosleep.clockid = type;
|
restart->nanosleep.expires = exp;
|
set_restart_fn(restart, alarm_timer_nsleep_restart);
|
return ret;
|
}
|
|
const struct k_clock alarm_clock = {
|
.clock_getres = alarm_clock_getres,
|
.clock_get_ktime = alarm_clock_get_ktime,
|
.clock_get_timespec = alarm_clock_get_timespec,
|
.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,
|
.timer_wait_running = alarm_timer_wait_running,
|
.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,
|
}
|
};
|
|
static void get_boottime_timespec(struct timespec64 *tp)
|
{
|
ktime_get_boottime_ts64(tp);
|
timens_add_boottime(tp);
|
}
|
|
/**
|
* alarmtimer_init - Initialize alarm timer code
|
*
|
* This function initializes the alarm bases and registers
|
* the posix clock ids.
|
*/
|
static int __init alarmtimer_init(void)
|
{
|
int error;
|
int i;
|
|
alarmtimer_rtc_timer_init();
|
|
/* Initialize alarm bases */
|
alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
|
alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
|
alarm_bases[ALARM_REALTIME].get_timespec = ktime_get_real_ts64;
|
alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
|
alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
|
alarm_bases[ALARM_BOOTTIME].get_timespec = get_boottime_timespec;
|
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;
|
|
return 0;
|
out_if:
|
alarmtimer_rtc_interface_remove();
|
return error;
|
}
|
device_initcall(alarmtimer_init);
|
