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
9 struct rtc_device;
10
11 enum 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 */
36 struct 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
45 void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
46 void (*function)(struct alarm *, ktime_t));
47 void alarm_start(struct alarm *alarm, ktime_t start);
48 void alarm_start_relative(struct alarm *alarm, ktime_t start);
49 void alarm_restart(struct alarm *alarm);
50 int alarm_try_to_cancel(struct alarm *alarm);
51 int alarm_cancel(struct alarm *alarm);
52
53 u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);
54 u64 alarm_forward_now(struct alarm *alarm, ktime_t interval);
55 ktime_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 */
59 struct rtc_device *alarmtimer_get_rtcdev(void);
60 #else
alarmtimer_get_rtcdev(void)61 static inline struct rtc_device *alarmtimer_get_rtcdev(void) { return NULL; }
62 #endif
63
64 #endif
65