linux-stable/include/linux/alarmtimer.h
Todd Poynor 6cffe00f7d alarmtimer: Add functions for timerfd support
Add functions needed for hooking up alarmtimer to timerfd:

* alarm_restart: Similar to hrtimer_restart, restart an alarmtimer after
  the expires time has already been updated (as with alarm_forward).

* alarm_forward_now: Similar to hrtimer_forward_now, move the expires
  time forward to an interval from the current time of the associated clock.

* alarm_start_relative: Start an alarmtimer with an expires time relative to
  the current time of the associated clock.

* alarm_expires_remaining: Similar to hrtimer_expires_remaining, return the
  amount of time remaining until alarm expiry.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-05-29 12:57:34 -07:00

59 lines
1.6 KiB
C

#ifndef _LINUX_ALARMTIMER_H
#define _LINUX_ALARMTIMER_H
#include <linux/time.h>
#include <linux/hrtimer.h>
#include <linux/timerqueue.h>
#include <linux/rtc.h>
enum alarmtimer_type {
ALARM_REALTIME,
ALARM_BOOTTIME,
ALARM_NUMTYPE,
};
enum alarmtimer_restart {
ALARMTIMER_NORESTART,
ALARMTIMER_RESTART,
};
#define ALARMTIMER_STATE_INACTIVE 0x00
#define ALARMTIMER_STATE_ENQUEUED 0x01
/**
* struct alarm - Alarm timer structure
* @node: timerqueue node for adding to the event list this value
* also includes the expiration time.
* @period: Period for recuring alarms
* @function: Function pointer to be executed when the timer fires.
* @type: Alarm type (BOOTTIME/REALTIME)
* @enabled: Flag that represents if the alarm is set to fire or not
* @data: Internal data value.
*/
struct alarm {
struct timerqueue_node node;
struct hrtimer timer;
enum alarmtimer_restart (*function)(struct alarm *, ktime_t now);
enum alarmtimer_type type;
int state;
void *data;
};
void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
enum alarmtimer_restart (*function)(struct alarm *, ktime_t));
int alarm_start(struct alarm *alarm, ktime_t start);
int alarm_start_relative(struct alarm *alarm, ktime_t start);
void alarm_restart(struct alarm *alarm);
int alarm_try_to_cancel(struct alarm *alarm);
int alarm_cancel(struct alarm *alarm);
u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);
u64 alarm_forward_now(struct alarm *alarm, ktime_t interval);
ktime_t alarm_expires_remaining(const struct alarm *alarm);
/* Provide way to access the rtc device being used by alarmtimers */
struct rtc_device *alarmtimer_get_rtcdev(void);
#endif