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
9struct rtc_device;
10
11enum alarmtimer_type {
12 ALARM_REALTIME,
13 ALARM_BOOTTIME,
14
15 /* Supported types end here */
16 ALARM_NUMTYPE,
17
18 /* Used for tracing information. No usable types. */
19 ALARM_REALTIME_FREEZER,
20 ALARM_BOOTTIME_FREEZER,
21};
22
23#define ALARMTIMER_STATE_INACTIVE 0x00
24#define ALARMTIMER_STATE_ENQUEUED 0x01
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 * @timer: hrtimer used to schedule events while running
31 * @function: Function pointer to be executed when the timer fires.
32 * @type: Alarm type (BOOTTIME/REALTIME).
33 * @state: 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 struct hrtimer timer;
39 void (*function)(struct alarm *, ktime_t now);
40 enum alarmtimer_type type;
41 int state;
42 void *data;
43};
44
45void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
46 void (*function)(struct alarm *, ktime_t));
47void alarm_start(struct alarm *alarm, ktime_t start);
48void alarm_start_relative(struct alarm *alarm, ktime_t start);
49void alarm_restart(struct alarm *alarm);
50int alarm_try_to_cancel(struct alarm *alarm);
51int alarm_cancel(struct alarm *alarm);
52
53u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);
54u64 alarm_forward_now(struct alarm *alarm, ktime_t interval);
55ktime_t alarm_expires_remaining(const struct alarm *alarm);
56
57#ifdef CONFIG_RTC_CLASS
58/* Provide way to access the rtc device being used by alarmtimers */
59struct rtc_device *alarmtimer_get_rtcdev(void);
60#else
61static inline struct rtc_device *alarmtimer_get_rtcdev(void) { return NULL; }
62#endif
63
64#endif
65