1 /* drivers/rtc/alarm-dev.c
3 * Copyright (C) 2007-2009 Google, Inc.
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
16 #include <linux/time.h>
17 #include <linux/module.h>
18 #include <linux/device.h>
19 #include <linux/miscdevice.h>
21 #include <linux/platform_device.h>
22 #include <linux/sched.h>
23 #include <linux/spinlock.h>
24 #include <linux/uaccess.h>
25 #include <linux/alarmtimer.h>
26 #include "android_alarm.h"
28 #define ANDROID_ALARM_PRINT_INFO (1U << 0)
29 #define ANDROID_ALARM_PRINT_IO (1U << 1)
30 #define ANDROID_ALARM_PRINT_INT (1U << 2)
32 static int debug_mask = ANDROID_ALARM_PRINT_INFO;
33 module_param_named(debug_mask, debug_mask, int, S_IRUGO | S_IWUSR | S_IWGRP);
35 #define alarm_dbg(debug_level_mask, fmt, ...) \
37 if (debug_mask & ANDROID_ALARM_PRINT_##debug_level_mask) \
38 pr_info(fmt, ##__VA_ARGS__); \
41 #define ANDROID_ALARM_WAKEUP_MASK ( \
42 ANDROID_ALARM_RTC_WAKEUP_MASK | \
43 ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP_MASK)
45 static int alarm_opened;
46 static DEFINE_SPINLOCK(alarm_slock);
47 static struct wakeup_source alarm_wake_lock;
48 static DECLARE_WAIT_QUEUE_HEAD(alarm_wait_queue);
49 static uint32_t alarm_pending;
50 static uint32_t alarm_enabled;
51 static uint32_t wait_pending;
58 enum android_alarm_type type;
61 static struct devalarm alarms[ANDROID_ALARM_TYPE_COUNT];
64 static int is_wakeup(enum android_alarm_type type)
66 return (type == ANDROID_ALARM_RTC_WAKEUP ||
67 type == ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP);
71 static void devalarm_start(struct devalarm *alrm, ktime_t exp)
73 if (is_wakeup(alrm->type))
74 alarm_start(&alrm->u.alrm, exp);
76 hrtimer_start(&alrm->u.hrt, exp, HRTIMER_MODE_ABS);
80 static int devalarm_try_to_cancel(struct devalarm *alrm)
82 if (is_wakeup(alrm->type))
83 return alarm_try_to_cancel(&alrm->u.alrm);
84 return hrtimer_try_to_cancel(&alrm->u.hrt);
87 static void devalarm_cancel(struct devalarm *alrm)
89 if (is_wakeup(alrm->type))
90 alarm_cancel(&alrm->u.alrm);
92 hrtimer_cancel(&alrm->u.hrt);
95 static void alarm_clear(enum android_alarm_type alarm_type)
97 uint32_t alarm_type_mask = 1U << alarm_type;
100 spin_lock_irqsave(&alarm_slock, flags);
101 alarm_dbg(IO, "alarm %d clear\n", alarm_type);
102 devalarm_try_to_cancel(&alarms[alarm_type]);
104 alarm_pending &= ~alarm_type_mask;
105 if (!alarm_pending && !wait_pending)
106 __pm_relax(&alarm_wake_lock);
108 alarm_enabled &= ~alarm_type_mask;
109 spin_unlock_irqrestore(&alarm_slock, flags);
113 static void alarm_set(enum android_alarm_type alarm_type,
116 uint32_t alarm_type_mask = 1U << alarm_type;
119 spin_lock_irqsave(&alarm_slock, flags);
120 alarm_dbg(IO, "alarm %d set %ld.%09ld\n",
121 alarm_type, ts->tv_sec, ts->tv_nsec);
122 alarm_enabled |= alarm_type_mask;
123 devalarm_start(&alarms[alarm_type], timespec_to_ktime(*ts));
124 spin_unlock_irqrestore(&alarm_slock, flags);
127 static int alarm_wait(void)
132 spin_lock_irqsave(&alarm_slock, flags);
133 alarm_dbg(IO, "alarm wait\n");
134 if (!alarm_pending && wait_pending) {
135 __pm_relax(&alarm_wake_lock);
138 spin_unlock_irqrestore(&alarm_slock, flags);
140 rv = wait_event_interruptible(alarm_wait_queue, alarm_pending);
144 spin_lock_irqsave(&alarm_slock, flags);
148 spin_unlock_irqrestore(&alarm_slock, flags);
153 static int alarm_set_rtc(struct timespec *ts)
155 struct rtc_time new_rtc_tm;
156 struct rtc_device *rtc_dev;
160 rtc_time_to_tm(ts->tv_sec, &new_rtc_tm);
161 rtc_dev = alarmtimer_get_rtcdev();
162 rv = do_settimeofday(ts);
166 rv = rtc_set_time(rtc_dev, &new_rtc_tm);
168 spin_lock_irqsave(&alarm_slock, flags);
169 alarm_pending |= ANDROID_ALARM_TIME_CHANGE_MASK;
170 wake_up(&alarm_wait_queue);
171 spin_unlock_irqrestore(&alarm_slock, flags);
176 static int alarm_get_time(enum android_alarm_type alarm_type,
181 switch (alarm_type) {
182 case ANDROID_ALARM_RTC_WAKEUP:
183 case ANDROID_ALARM_RTC:
186 case ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP:
187 case ANDROID_ALARM_ELAPSED_REALTIME:
188 get_monotonic_boottime(ts);
190 case ANDROID_ALARM_SYSTEMTIME:
199 static long alarm_do_ioctl(struct file *file, unsigned int cmd,
204 enum android_alarm_type alarm_type = ANDROID_ALARM_IOCTL_TO_TYPE(cmd);
206 if (alarm_type >= ANDROID_ALARM_TYPE_COUNT)
209 if (ANDROID_ALARM_BASE_CMD(cmd) != ANDROID_ALARM_GET_TIME(0)) {
210 if ((file->f_flags & O_ACCMODE) == O_RDONLY)
212 if (file->private_data == NULL &&
213 cmd != ANDROID_ALARM_SET_RTC) {
214 spin_lock_irqsave(&alarm_slock, flags);
216 spin_unlock_irqrestore(&alarm_slock, flags);
220 file->private_data = (void *)1;
221 spin_unlock_irqrestore(&alarm_slock, flags);
225 switch (ANDROID_ALARM_BASE_CMD(cmd)) {
226 case ANDROID_ALARM_CLEAR(0):
227 alarm_clear(alarm_type);
229 case ANDROID_ALARM_SET(0):
230 alarm_set(alarm_type, ts);
232 case ANDROID_ALARM_SET_AND_WAIT(0):
233 alarm_set(alarm_type, ts);
235 case ANDROID_ALARM_WAIT:
238 case ANDROID_ALARM_SET_RTC:
239 rv = alarm_set_rtc(ts);
241 case ANDROID_ALARM_GET_TIME(0):
242 rv = alarm_get_time(alarm_type, ts);
251 static long alarm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
257 switch (ANDROID_ALARM_BASE_CMD(cmd)) {
258 case ANDROID_ALARM_SET_AND_WAIT(0):
259 case ANDROID_ALARM_SET(0):
260 case ANDROID_ALARM_SET_RTC:
261 if (copy_from_user(&ts, (void __user *)arg, sizeof(ts)))
266 rv = alarm_do_ioctl(file, cmd, &ts);
270 switch (ANDROID_ALARM_BASE_CMD(cmd)) {
271 case ANDROID_ALARM_GET_TIME(0):
272 if (copy_to_user((void __user *)arg, &ts, sizeof(ts)))
280 static long alarm_compat_ioctl(struct file *file, unsigned int cmd,
287 switch (ANDROID_ALARM_BASE_CMD(cmd)) {
288 case ANDROID_ALARM_SET_AND_WAIT_COMPAT(0):
289 case ANDROID_ALARM_SET_COMPAT(0):
290 case ANDROID_ALARM_SET_RTC_COMPAT:
291 if (compat_get_timespec(&ts, (void __user *)arg))
294 case ANDROID_ALARM_GET_TIME_COMPAT(0):
295 cmd = ANDROID_ALARM_COMPAT_TO_NORM(cmd);
299 rv = alarm_do_ioctl(file, cmd, &ts);
301 switch (ANDROID_ALARM_BASE_CMD(cmd)) {
302 case ANDROID_ALARM_GET_TIME(0): /* NOTE: we modified cmd above */
303 if (compat_put_timespec(&ts, (void __user *)arg))
312 static int alarm_open(struct inode *inode, struct file *file)
314 file->private_data = NULL;
318 static int alarm_release(struct inode *inode, struct file *file)
323 spin_lock_irqsave(&alarm_slock, flags);
324 if (file->private_data) {
325 for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++) {
326 uint32_t alarm_type_mask = 1U << i;
327 if (alarm_enabled & alarm_type_mask) {
329 "%s: clear alarm, pending %d\n",
331 !!(alarm_pending & alarm_type_mask));
332 alarm_enabled &= ~alarm_type_mask;
334 spin_unlock_irqrestore(&alarm_slock, flags);
335 devalarm_cancel(&alarms[i]);
336 spin_lock_irqsave(&alarm_slock, flags);
338 if (alarm_pending | wait_pending) {
340 alarm_dbg(INFO, "%s: clear pending alarms %x\n",
341 __func__, alarm_pending);
342 __pm_relax(&alarm_wake_lock);
348 spin_unlock_irqrestore(&alarm_slock, flags);
352 static void devalarm_triggered(struct devalarm *alarm)
355 uint32_t alarm_type_mask = 1U << alarm->type;
357 alarm_dbg(INT, "%s: type %d\n", __func__, alarm->type);
358 spin_lock_irqsave(&alarm_slock, flags);
359 if (alarm_enabled & alarm_type_mask) {
360 __pm_wakeup_event(&alarm_wake_lock, 5000); /* 5secs */
361 alarm_enabled &= ~alarm_type_mask;
362 alarm_pending |= alarm_type_mask;
363 wake_up(&alarm_wait_queue);
365 spin_unlock_irqrestore(&alarm_slock, flags);
369 static enum hrtimer_restart devalarm_hrthandler(struct hrtimer *hrt)
371 struct devalarm *devalrm = container_of(hrt, struct devalarm, u.hrt);
373 devalarm_triggered(devalrm);
374 return HRTIMER_NORESTART;
377 static enum alarmtimer_restart devalarm_alarmhandler(struct alarm *alrm,
380 struct devalarm *devalrm = container_of(alrm, struct devalarm, u.alrm);
382 devalarm_triggered(devalrm);
383 return ALARMTIMER_NORESTART;
387 static const struct file_operations alarm_fops = {
388 .owner = THIS_MODULE,
389 .unlocked_ioctl = alarm_ioctl,
391 .release = alarm_release,
393 .compat_ioctl = alarm_compat_ioctl,
397 static struct miscdevice alarm_device = {
398 .minor = MISC_DYNAMIC_MINOR,
403 static int __init alarm_dev_init(void)
408 err = misc_register(&alarm_device);
412 alarm_init(&alarms[ANDROID_ALARM_RTC_WAKEUP].u.alrm,
413 ALARM_REALTIME, devalarm_alarmhandler);
414 hrtimer_init(&alarms[ANDROID_ALARM_RTC].u.hrt,
415 CLOCK_REALTIME, HRTIMER_MODE_ABS);
416 alarm_init(&alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP].u.alrm,
417 ALARM_BOOTTIME, devalarm_alarmhandler);
418 hrtimer_init(&alarms[ANDROID_ALARM_ELAPSED_REALTIME].u.hrt,
419 CLOCK_BOOTTIME, HRTIMER_MODE_ABS);
420 hrtimer_init(&alarms[ANDROID_ALARM_SYSTEMTIME].u.hrt,
421 CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
423 for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++) {
426 alarms[i].u.hrt.function = devalarm_hrthandler;
429 wakeup_source_init(&alarm_wake_lock, "alarm");
433 static void __exit alarm_dev_exit(void)
435 misc_deregister(&alarm_device);
436 wakeup_source_trash(&alarm_wake_lock);
439 module_init(alarm_dev_init);
440 module_exit(alarm_dev_exit);