LXR linux/include/linux/alarmtimer.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_ALARMTIMER_H
   3#define _LINUX_ALARMTIMER_H
   4
   5#include <linux/time.h>
   6#include <linux/hrtimer.h>
   7#include <linux/timerqueue.h>
   8#include <linux/rtc.h>
   9
  10enum alarmtimer_type {
  11        ALARM_REALTIME,
  12        ALARM_BOOTTIME,
  13
  14        /* Supported types end here */
  15        ALARM_NUMTYPE,
  16
  17        /* Used for tracing information. No usable types. */
  18        ALARM_REALTIME_FREEZER,
  19        ALARM_BOOTTIME_FREEZER,
  20};
  21
  22enum alarmtimer_restart {
  23        ALARMTIMER_NORESTART,
  24        ALARMTIMER_RESTART,
  25};
  26
  27
  28#define ALARMTIMER_STATE_INACTIVE       0x00
  29#define ALARMTIMER_STATE_ENQUEUED       0x01
  30
  31/**
  32 * struct alarm - Alarm timer structure
  33 * @node:       timerqueue node for adding to the event list this value
  34 *              also includes the expiration time.
  35 * @timer:      hrtimer used to schedule events while running
  36 * @function:   Function pointer to be executed when the timer fires.
  37 * @type:       Alarm type (BOOTTIME/REALTIME).
  38 * @state:      Flag that represents if the alarm is set to fire or not.
  39 * @data:       Internal data value.
  40 */
  41struct alarm {
  42        struct timerqueue_node  node;
  43        struct hrtimer          timer;
  44        enum alarmtimer_restart (*function)(struct alarm *, ktime_t now);
  45        enum alarmtimer_type    type;
  46        int                     state;
  47        void                    *data;
  48};
  49
  50void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
  51                enum alarmtimer_restart (*function)(struct alarm *, ktime_t));
  52void alarm_start(struct alarm *alarm, ktime_t start);
  53void alarm_start_relative(struct alarm *alarm, ktime_t start);
  54void alarm_restart(struct alarm *alarm);
  55int alarm_try_to_cancel(struct alarm *alarm);
  56int alarm_cancel(struct alarm *alarm);
  57
  58u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);
  59u64 alarm_forward_now(struct alarm *alarm, ktime_t interval);
  60ktime_t alarm_expires_remaining(const struct alarm *alarm);
  61
  62/* Provide way to access the rtc device being used by alarmtimers */
  63struct rtc_device *alarmtimer_get_rtcdev(void);
  64
  65#endif
  66