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
23enum alarmtimer_restart {
24	ALARMTIMER_NORESTART,
25	ALARMTIMER_RESTART,
26};
27
28
29#define ALARMTIMER_STATE_INACTIVE	0x00
30#define ALARMTIMER_STATE_ENQUEUED	0x01
31
32/**
33 * struct alarm - Alarm timer structure
34 * @node:	timerqueue node for adding to the event list this value
35 *		also includes the expiration time.
36 * @timer:	hrtimer used to schedule events while running
37 * @function:	Function pointer to be executed when the timer fires.
38 * @type:	Alarm type (BOOTTIME/REALTIME).
39 * @state:	Flag that represents if the alarm is set to fire or not.
40 * @data:	Internal data value.
41 */
42struct alarm {
43	struct timerqueue_node	node;
44	struct hrtimer		timer;
45	enum alarmtimer_restart	(*function)(struct alarm *, ktime_t now);
46	enum alarmtimer_type	type;
47	int			state;
48	void			*data;
49};
50
51void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
52		enum alarmtimer_restart (*function)(struct alarm *, ktime_t));
53void alarm_start(struct alarm *alarm, ktime_t start);
54void alarm_start_relative(struct alarm *alarm, ktime_t start);
55void alarm_restart(struct alarm *alarm);
56int alarm_try_to_cancel(struct alarm *alarm);
57int alarm_cancel(struct alarm *alarm);
58
59u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);
60u64 alarm_forward_now(struct alarm *alarm, ktime_t interval);
61ktime_t alarm_expires_remaining(const struct alarm *alarm);
62
63#ifdef CONFIG_RTC_CLASS
64/* Provide way to access the rtc device being used by alarmtimers */
65struct rtc_device *alarmtimer_get_rtcdev(void);
66#else
67static inline struct rtc_device *alarmtimer_get_rtcdev(void) { return NULL; }
68#endif
69
70#endif
71