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);
96 static long alarm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
100 struct timespec new_alarm_time;
101 struct timespec new_rtc_time;
102 struct timespec tmp_time;
103 struct rtc_time new_rtc_tm;
104 struct rtc_device *rtc_dev;
105 enum android_alarm_type alarm_type = ANDROID_ALARM_IOCTL_TO_TYPE(cmd);
106 uint32_t alarm_type_mask = 1U << alarm_type;
108 if (alarm_type >= ANDROID_ALARM_TYPE_COUNT)
111 if (ANDROID_ALARM_BASE_CMD(cmd) != ANDROID_ALARM_GET_TIME(0)) {
112 if ((file->f_flags & O_ACCMODE) == O_RDONLY)
114 if (file->private_data == NULL &&
115 cmd != ANDROID_ALARM_SET_RTC) {
116 spin_lock_irqsave(&alarm_slock, flags);
118 spin_unlock_irqrestore(&alarm_slock, flags);
122 file->private_data = (void *)1;
123 spin_unlock_irqrestore(&alarm_slock, flags);
127 switch (ANDROID_ALARM_BASE_CMD(cmd)) {
128 case ANDROID_ALARM_CLEAR(0):
129 spin_lock_irqsave(&alarm_slock, flags);
130 alarm_dbg(IO, "alarm %d clear\n", alarm_type);
131 devalarm_try_to_cancel(&alarms[alarm_type]);
133 alarm_pending &= ~alarm_type_mask;
134 if (!alarm_pending && !wait_pending)
135 __pm_relax(&alarm_wake_lock);
137 alarm_enabled &= ~alarm_type_mask;
138 spin_unlock_irqrestore(&alarm_slock, flags);
141 case ANDROID_ALARM_SET_AND_WAIT(0):
142 case ANDROID_ALARM_SET(0):
143 if (copy_from_user(&new_alarm_time, (void __user *)arg,
144 sizeof(new_alarm_time))) {
148 spin_lock_irqsave(&alarm_slock, flags);
149 alarm_dbg(IO, "alarm %d set %ld.%09ld\n",
151 new_alarm_time.tv_sec, new_alarm_time.tv_nsec);
152 alarm_enabled |= alarm_type_mask;
153 devalarm_start(&alarms[alarm_type],
154 timespec_to_ktime(new_alarm_time));
155 spin_unlock_irqrestore(&alarm_slock, flags);
156 if (ANDROID_ALARM_BASE_CMD(cmd) !=
157 ANDROID_ALARM_SET_AND_WAIT(0))
160 case ANDROID_ALARM_WAIT:
161 spin_lock_irqsave(&alarm_slock, flags);
162 alarm_dbg(IO, "alarm wait\n");
163 if (!alarm_pending && wait_pending) {
164 __pm_relax(&alarm_wake_lock);
167 spin_unlock_irqrestore(&alarm_slock, flags);
168 rv = wait_event_interruptible(alarm_wait_queue, alarm_pending);
171 spin_lock_irqsave(&alarm_slock, flags);
175 spin_unlock_irqrestore(&alarm_slock, flags);
177 case ANDROID_ALARM_SET_RTC:
178 if (copy_from_user(&new_rtc_time, (void __user *)arg,
179 sizeof(new_rtc_time))) {
183 rtc_time_to_tm(new_rtc_time.tv_sec, &new_rtc_tm);
184 rtc_dev = alarmtimer_get_rtcdev();
185 rv = do_settimeofday(&new_rtc_time);
189 rv = rtc_set_time(rtc_dev, &new_rtc_tm);
190 spin_lock_irqsave(&alarm_slock, flags);
191 alarm_pending |= ANDROID_ALARM_TIME_CHANGE_MASK;
192 wake_up(&alarm_wait_queue);
193 spin_unlock_irqrestore(&alarm_slock, flags);
197 case ANDROID_ALARM_GET_TIME(0):
198 switch (alarm_type) {
199 case ANDROID_ALARM_RTC_WAKEUP:
200 case ANDROID_ALARM_RTC:
201 getnstimeofday(&tmp_time);
203 case ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP:
204 case ANDROID_ALARM_ELAPSED_REALTIME:
205 get_monotonic_boottime(&tmp_time);
207 case ANDROID_ALARM_SYSTEMTIME:
208 ktime_get_ts(&tmp_time);
214 if (copy_to_user((void __user *)arg, &tmp_time,
228 static int alarm_open(struct inode *inode, struct file *file)
230 file->private_data = NULL;
234 static int alarm_release(struct inode *inode, struct file *file)
239 spin_lock_irqsave(&alarm_slock, flags);
240 if (file->private_data) {
241 for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++) {
242 uint32_t alarm_type_mask = 1U << i;
243 if (alarm_enabled & alarm_type_mask) {
245 "%s: clear alarm, pending %d\n",
247 !!(alarm_pending & alarm_type_mask));
248 alarm_enabled &= ~alarm_type_mask;
250 spin_unlock_irqrestore(&alarm_slock, flags);
251 devalarm_cancel(&alarms[i]);
252 spin_lock_irqsave(&alarm_slock, flags);
254 if (alarm_pending | wait_pending) {
256 alarm_dbg(INFO, "%s: clear pending alarms %x\n",
257 __func__, alarm_pending);
258 __pm_relax(&alarm_wake_lock);
264 spin_unlock_irqrestore(&alarm_slock, flags);
268 static void devalarm_triggered(struct devalarm *alarm)
271 uint32_t alarm_type_mask = 1U << alarm->type;
273 alarm_dbg(INT, "%s: type %d\n", __func__, alarm->type);
274 spin_lock_irqsave(&alarm_slock, flags);
275 if (alarm_enabled & alarm_type_mask) {
276 __pm_wakeup_event(&alarm_wake_lock, 5000); /* 5secs */
277 alarm_enabled &= ~alarm_type_mask;
278 alarm_pending |= alarm_type_mask;
279 wake_up(&alarm_wait_queue);
281 spin_unlock_irqrestore(&alarm_slock, flags);
285 static enum hrtimer_restart devalarm_hrthandler(struct hrtimer *hrt)
287 struct devalarm *devalrm = container_of(hrt, struct devalarm, u.hrt);
289 devalarm_triggered(devalrm);
290 return HRTIMER_NORESTART;
293 static enum alarmtimer_restart devalarm_alarmhandler(struct alarm *alrm,
296 struct devalarm *devalrm = container_of(alrm, struct devalarm, u.alrm);
298 devalarm_triggered(devalrm);
299 return ALARMTIMER_NORESTART;
303 static const struct file_operations alarm_fops = {
304 .owner = THIS_MODULE,
305 .unlocked_ioctl = alarm_ioctl,
307 .release = alarm_release,
310 static struct miscdevice alarm_device = {
311 .minor = MISC_DYNAMIC_MINOR,
316 static int __init alarm_dev_init(void)
321 err = misc_register(&alarm_device);
325 alarm_init(&alarms[ANDROID_ALARM_RTC_WAKEUP].u.alrm,
326 ALARM_REALTIME, devalarm_alarmhandler);
327 hrtimer_init(&alarms[ANDROID_ALARM_RTC].u.hrt,
328 CLOCK_REALTIME, HRTIMER_MODE_ABS);
329 alarm_init(&alarms[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP].u.alrm,
330 ALARM_BOOTTIME, devalarm_alarmhandler);
331 hrtimer_init(&alarms[ANDROID_ALARM_ELAPSED_REALTIME].u.hrt,
332 CLOCK_BOOTTIME, HRTIMER_MODE_ABS);
333 hrtimer_init(&alarms[ANDROID_ALARM_SYSTEMTIME].u.hrt,
334 CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
336 for (i = 0; i < ANDROID_ALARM_TYPE_COUNT; i++) {
339 alarms[i].u.hrt.function = devalarm_hrthandler;
342 wakeup_source_init(&alarm_wake_lock, "alarm");
346 static void __exit alarm_dev_exit(void)
348 misc_deregister(&alarm_device);
349 wakeup_source_trash(&alarm_wake_lock);
352 module_init(alarm_dev_init);
353 module_exit(alarm_dev_exit);