Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1#ifndef _LINUX_ALARMTIMER_H
2#define _LINUX_ALARMTIMER_H
3
4#include <linux/time.h>
5#include <linux/hrtimer.h>
6#include <linux/timerqueue.h>
7#include <linux/rtc.h>
8
9enum alarmtimer_type {
10 ALARM_REALTIME,
11 ALARM_BOOTTIME,
12
13 ALARM_NUMTYPE,
14};
15
16enum alarmtimer_restart {
17 ALARMTIMER_NORESTART,
18 ALARMTIMER_RESTART,
19};
20
21
22#define ALARMTIMER_STATE_INACTIVE 0x00
23#define ALARMTIMER_STATE_ENQUEUED 0x01
24#define ALARMTIMER_STATE_CALLBACK 0x02
25
26/**
27 * struct alarm - Alarm timer structure
28 * @node: timerqueue node for adding to the event list this value
29 * also includes the expiration time.
30 * @period: Period for recuring alarms
31 * @function: Function pointer to be executed when the timer fires.
32 * @type: Alarm type (BOOTTIME/REALTIME)
33 * @enabled: Flag that represents if the alarm is set to fire or not
34 * @data: Internal data value.
35 */
36struct alarm {
37 struct timerqueue_node node;
38 enum alarmtimer_restart (*function)(struct alarm *, ktime_t now);
39 enum alarmtimer_type type;
40 int state;
41 void *data;
42};
43
44void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
45 enum alarmtimer_restart (*function)(struct alarm *, ktime_t));
46void alarm_start(struct alarm *alarm, ktime_t start);
47int alarm_try_to_cancel(struct alarm *alarm);
48int alarm_cancel(struct alarm *alarm);
49
50u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);
51
52/*
53 * A alarmtimer is active, when it is enqueued into timerqueue or the
54 * callback function is running.
55 */
56static inline int alarmtimer_active(const struct alarm *timer)
57{
58 return timer->state != ALARMTIMER_STATE_INACTIVE;
59}
60
61/*
62 * Helper function to check, whether the timer is on one of the queues
63 */
64static inline int alarmtimer_is_queued(struct alarm *timer)
65{
66 return timer->state & ALARMTIMER_STATE_ENQUEUED;
67}
68
69/*
70 * Helper function to check, whether the timer is running the callback
71 * function
72 */
73static inline int alarmtimer_callback_running(struct alarm *timer)
74{
75 return timer->state & ALARMTIMER_STATE_CALLBACK;
76}
77
78
79/* Provide way to access the rtc device being used by alarmtimers */
80struct rtc_device *alarmtimer_get_rtcdev(void);
81
82#endif