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>
20 #include <linux/platform_device.h>
21 #include <linux/rtc.h>
22 #include <linux/sched.h>
23 #include <linux/spinlock.h>
24 #include "android_alarm.h"
26 /* XXX - Hack out wakelocks, while they are out of tree */
31 #define wake_lock_timeout(x, y)
32 #define wake_unlock(x)
33 #define WAKE_LOCK_SUSPEND 0
34 #define wake_lock_init(x, y, z) ((x)->i = 1)
35 #define wake_lock_destroy(x)
37 #define ANDROID_ALARM_PRINT_ERROR (1U << 0)
38 #define ANDROID_ALARM_PRINT_INIT_STATUS (1U << 1)
39 #define ANDROID_ALARM_PRINT_TSET (1U << 2)
40 #define ANDROID_ALARM_PRINT_CALL (1U << 3)
41 #define ANDROID_ALARM_PRINT_SUSPEND (1U << 4)
42 #define ANDROID_ALARM_PRINT_INT (1U << 5)
43 #define ANDROID_ALARM_PRINT_FLOW (1U << 6)
45 static int debug_mask
= ANDROID_ALARM_PRINT_ERROR
| \
46 ANDROID_ALARM_PRINT_INIT_STATUS
;
47 module_param_named(debug_mask
, debug_mask
, int, S_IRUGO
| S_IWUSR
| S_IWGRP
);
49 #define pr_alarm(debug_level_mask, args...) \
51 if (debug_mask & ANDROID_ALARM_PRINT_##debug_level_mask) { \
56 #define ANDROID_ALARM_WAKEUP_MASK ( \
57 ANDROID_ALARM_RTC_WAKEUP_MASK | \
58 ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP_MASK)
60 /* support old usespace code */
61 #define ANDROID_ALARM_SET_OLD _IOW('a', 2, time_t) /* set alarm */
62 #define ANDROID_ALARM_SET_AND_WAIT_OLD _IOW('a', 3, time_t)
65 struct rb_root alarms
;
66 struct rb_node
*first
;
73 static struct rtc_device
*alarm_rtc_dev
;
74 static DEFINE_SPINLOCK(alarm_slock
);
75 static DEFINE_MUTEX(alarm_setrtc_mutex
);
76 static struct wake_lock alarm_rtc_wake_lock
;
77 static struct platform_device
*alarm_platform_dev
;
78 struct alarm_queue alarms
[ANDROID_ALARM_TYPE_COUNT
];
79 static bool suspended
;
81 static void update_timer_locked(struct alarm_queue
*base
, bool head_removed
)
83 struct android_alarm
*alarm
;
84 bool is_wakeup
= base
== &alarms
[ANDROID_ALARM_RTC_WAKEUP
] ||
85 base
== &alarms
[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP
];
88 pr_alarm(FLOW
, "changed alarm while setting the wall time\n");
92 if (is_wakeup
&& !suspended
&& head_removed
)
93 wake_unlock(&alarm_rtc_wake_lock
);
98 alarm
= container_of(base
->first
, struct android_alarm
, node
);
100 pr_alarm(FLOW
, "selected alarm, type %d, func %pF at %lld\n",
101 alarm
->type
, alarm
->function
, ktime_to_ns(alarm
->expires
));
103 if (is_wakeup
&& suspended
) {
104 pr_alarm(FLOW
, "changed alarm while suspened\n");
105 wake_lock_timeout(&alarm_rtc_wake_lock
, 1 * HZ
);
109 hrtimer_try_to_cancel(&base
->timer
);
110 base
->timer
.node
.expires
= ktime_add(base
->delta
, alarm
->expires
);
111 base
->timer
._softexpires
= ktime_add(base
->delta
, alarm
->softexpires
);
112 hrtimer_start_expires(&base
->timer
, HRTIMER_MODE_ABS
);
115 static void alarm_enqueue_locked(struct android_alarm
*alarm
)
117 struct alarm_queue
*base
= &alarms
[alarm
->type
];
118 struct rb_node
**link
= &base
->alarms
.rb_node
;
119 struct rb_node
*parent
= NULL
;
120 struct android_alarm
*entry
;
122 bool was_first
= false;
124 pr_alarm(FLOW
, "added alarm, type %d, func %pF at %lld\n",
125 alarm
->type
, alarm
->function
, ktime_to_ns(alarm
->expires
));
127 if (base
->first
== &alarm
->node
) {
128 base
->first
= rb_next(&alarm
->node
);
131 if (!RB_EMPTY_NODE(&alarm
->node
)) {
132 rb_erase(&alarm
->node
, &base
->alarms
);
133 RB_CLEAR_NODE(&alarm
->node
);
138 entry
= rb_entry(parent
, struct android_alarm
, node
);
140 * We dont care about collisions. Nodes with
141 * the same expiry time stay together.
143 if (alarm
->expires
.tv64
< entry
->expires
.tv64
) {
144 link
= &(*link
)->rb_left
;
146 link
= &(*link
)->rb_right
;
151 base
->first
= &alarm
->node
;
152 if (leftmost
|| was_first
)
153 update_timer_locked(base
, was_first
);
155 rb_link_node(&alarm
->node
, parent
, link
);
156 rb_insert_color(&alarm
->node
, &base
->alarms
);
160 * android_alarm_init - initialize an alarm
161 * @alarm: the alarm to be initialized
162 * @type: the alarm type to be used
163 * @function: alarm callback function
165 void android_alarm_init(struct android_alarm
*alarm
,
166 enum android_alarm_type type
, void (*function
)(struct android_alarm
*))
168 RB_CLEAR_NODE(&alarm
->node
);
170 alarm
->function
= function
;
172 pr_alarm(FLOW
, "created alarm, type %d, func %pF\n", type
, function
);
177 * android_alarm_start_range - (re)start an alarm
178 * @alarm: the alarm to be added
179 * @start: earliest expiry time
182 void android_alarm_start_range(struct android_alarm
*alarm
, ktime_t start
,
187 spin_lock_irqsave(&alarm_slock
, flags
);
188 alarm
->softexpires
= start
;
189 alarm
->expires
= end
;
190 alarm_enqueue_locked(alarm
);
191 spin_unlock_irqrestore(&alarm_slock
, flags
);
195 * android_alarm_try_to_cancel - try to deactivate an alarm
196 * @alarm: alarm to stop
199 * 0 when the alarm was not active
200 * 1 when the alarm was active
201 * -1 when the alarm may currently be excuting the callback function and
202 * cannot be stopped (it may also be inactive)
204 int android_alarm_try_to_cancel(struct android_alarm
*alarm
)
206 struct alarm_queue
*base
= &alarms
[alarm
->type
];
211 spin_lock_irqsave(&alarm_slock
, flags
);
212 if (!RB_EMPTY_NODE(&alarm
->node
)) {
213 pr_alarm(FLOW
, "canceled alarm, type %d, func %pF at %lld\n",
214 alarm
->type
, alarm
->function
,
215 ktime_to_ns(alarm
->expires
));
217 if (base
->first
== &alarm
->node
) {
218 base
->first
= rb_next(&alarm
->node
);
221 rb_erase(&alarm
->node
, &base
->alarms
);
222 RB_CLEAR_NODE(&alarm
->node
);
224 update_timer_locked(base
, true);
226 pr_alarm(FLOW
, "tried to cancel alarm, type %d, func %pF\n",
227 alarm
->type
, alarm
->function
);
228 spin_unlock_irqrestore(&alarm_slock
, flags
);
229 if (!ret
&& hrtimer_callback_running(&base
->timer
))
235 * android_alarm_cancel - cancel an alarm and wait for the handler to finish.
236 * @alarm: the alarm to be cancelled
239 * 0 when the alarm was not active
240 * 1 when the alarm was active
242 int android_alarm_cancel(struct android_alarm
*alarm
)
245 int ret
= android_alarm_try_to_cancel(alarm
);
253 * alarm_set_rtc - set the kernel and rtc walltime
254 * @new_time: timespec value containing the new time
256 int android_alarm_set_rtc(struct timespec new_time
)
261 struct rtc_time rtc_new_rtc_time
;
262 struct timespec tmp_time
;
264 rtc_time_to_tm(new_time
.tv_sec
, &rtc_new_rtc_time
);
266 pr_alarm(TSET
, "set rtc %ld %ld - rtc %02d:%02d:%02d %02d/%02d/%04d\n",
267 new_time
.tv_sec
, new_time
.tv_nsec
,
268 rtc_new_rtc_time
.tm_hour
, rtc_new_rtc_time
.tm_min
,
269 rtc_new_rtc_time
.tm_sec
, rtc_new_rtc_time
.tm_mon
+ 1,
270 rtc_new_rtc_time
.tm_mday
,
271 rtc_new_rtc_time
.tm_year
+ 1900);
273 mutex_lock(&alarm_setrtc_mutex
);
274 spin_lock_irqsave(&alarm_slock
, flags
);
275 wake_lock(&alarm_rtc_wake_lock
);
276 getnstimeofday(&tmp_time
);
277 for (i
= 0; i
< ANDROID_ALARM_SYSTEMTIME
; i
++) {
278 hrtimer_try_to_cancel(&alarms
[i
].timer
);
279 alarms
[i
].stopped
= true;
280 alarms
[i
].stopped_time
= timespec_to_ktime(tmp_time
);
282 alarms
[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP
].delta
=
283 alarms
[ANDROID_ALARM_ELAPSED_REALTIME
].delta
=
284 ktime_sub(alarms
[ANDROID_ALARM_ELAPSED_REALTIME
].delta
,
285 timespec_to_ktime(timespec_sub(tmp_time
, new_time
)));
286 spin_unlock_irqrestore(&alarm_slock
, flags
);
287 ret
= do_settimeofday(&new_time
);
288 spin_lock_irqsave(&alarm_slock
, flags
);
289 for (i
= 0; i
< ANDROID_ALARM_SYSTEMTIME
; i
++) {
290 alarms
[i
].stopped
= false;
291 update_timer_locked(&alarms
[i
], false);
293 spin_unlock_irqrestore(&alarm_slock
, flags
);
295 pr_alarm(ERROR
, "alarm_set_rtc: Failed to set time\n");
298 if (!alarm_rtc_dev
) {
300 "alarm_set_rtc: no RTC, time will be lost on reboot\n");
303 ret
= rtc_set_time(alarm_rtc_dev
, &rtc_new_rtc_time
);
305 pr_alarm(ERROR
, "alarm_set_rtc: "
306 "Failed to set RTC, time will be lost on reboot\n");
308 wake_unlock(&alarm_rtc_wake_lock
);
309 mutex_unlock(&alarm_setrtc_mutex
);
314 * alarm_get_elapsed_realtime - get the elapsed real time in ktime_t format
316 * returns the time in ktime_t format
318 ktime_t
alarm_get_elapsed_realtime(void)
322 struct alarm_queue
*base
= &alarms
[ANDROID_ALARM_ELAPSED_REALTIME
];
324 spin_lock_irqsave(&alarm_slock
, flags
);
325 now
= base
->stopped
? base
->stopped_time
: ktime_get_real();
326 now
= ktime_sub(now
, base
->delta
);
327 spin_unlock_irqrestore(&alarm_slock
, flags
);
331 static enum hrtimer_restart
alarm_timer_triggered(struct hrtimer
*timer
)
333 struct alarm_queue
*base
;
334 struct android_alarm
*alarm
;
338 spin_lock_irqsave(&alarm_slock
, flags
);
340 base
= container_of(timer
, struct alarm_queue
, timer
);
341 now
= base
->stopped
? base
->stopped_time
: hrtimer_cb_get_time(timer
);
342 now
= ktime_sub(now
, base
->delta
);
344 pr_alarm(INT
, "alarm_timer_triggered type %ld at %lld\n",
345 base
- alarms
, ktime_to_ns(now
));
347 while (base
->first
) {
348 alarm
= container_of(base
->first
, struct android_alarm
, node
);
349 if (alarm
->softexpires
.tv64
> now
.tv64
) {
350 pr_alarm(FLOW
, "don't call alarm, %pF, %lld (s %lld)\n",
351 alarm
->function
, ktime_to_ns(alarm
->expires
),
352 ktime_to_ns(alarm
->softexpires
));
355 base
->first
= rb_next(&alarm
->node
);
356 rb_erase(&alarm
->node
, &base
->alarms
);
357 RB_CLEAR_NODE(&alarm
->node
);
358 pr_alarm(CALL
, "call alarm, type %d, func %pF, %lld (s %lld)\n",
359 alarm
->type
, alarm
->function
,
360 ktime_to_ns(alarm
->expires
),
361 ktime_to_ns(alarm
->softexpires
));
362 spin_unlock_irqrestore(&alarm_slock
, flags
);
363 alarm
->function(alarm
);
364 spin_lock_irqsave(&alarm_slock
, flags
);
367 pr_alarm(FLOW
, "no more alarms of type %ld\n", base
- alarms
);
368 update_timer_locked(base
, true);
369 spin_unlock_irqrestore(&alarm_slock
, flags
);
370 return HRTIMER_NORESTART
;
373 static void alarm_triggered_func(void *p
)
375 struct rtc_device
*rtc
= alarm_rtc_dev
;
376 if (!(rtc
->irq_data
& RTC_AF
))
378 pr_alarm(INT
, "rtc alarm triggered\n");
379 wake_lock_timeout(&alarm_rtc_wake_lock
, 1 * HZ
);
382 static int alarm_suspend(struct platform_device
*pdev
, pm_message_t state
)
386 struct rtc_wkalrm rtc_alarm
;
387 struct rtc_time rtc_current_rtc_time
;
388 unsigned long rtc_current_time
;
389 unsigned long rtc_alarm_time
;
390 struct timespec rtc_delta
;
391 struct timespec wall_time
;
392 struct alarm_queue
*wakeup_queue
= NULL
;
393 struct alarm_queue
*tmp_queue
= NULL
;
395 pr_alarm(SUSPEND
, "alarm_suspend(%p, %d)\n", pdev
, state
.event
);
397 spin_lock_irqsave(&alarm_slock
, flags
);
399 spin_unlock_irqrestore(&alarm_slock
, flags
);
401 hrtimer_cancel(&alarms
[ANDROID_ALARM_RTC_WAKEUP
].timer
);
402 hrtimer_cancel(&alarms
[
403 ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP
].timer
);
405 tmp_queue
= &alarms
[ANDROID_ALARM_RTC_WAKEUP
];
406 if (tmp_queue
->first
)
407 wakeup_queue
= tmp_queue
;
408 tmp_queue
= &alarms
[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP
];
409 if (tmp_queue
->first
&& (!wakeup_queue
||
410 hrtimer_get_expires(&tmp_queue
->timer
).tv64
<
411 hrtimer_get_expires(&wakeup_queue
->timer
).tv64
))
412 wakeup_queue
= tmp_queue
;
414 rtc_read_time(alarm_rtc_dev
, &rtc_current_rtc_time
);
415 getnstimeofday(&wall_time
);
416 rtc_tm_to_time(&rtc_current_rtc_time
, &rtc_current_time
);
417 set_normalized_timespec(&rtc_delta
,
418 wall_time
.tv_sec
- rtc_current_time
,
421 rtc_alarm_time
= timespec_sub(ktime_to_timespec(
422 hrtimer_get_expires(&wakeup_queue
->timer
)),
425 rtc_time_to_tm(rtc_alarm_time
, &rtc_alarm
.time
);
426 rtc_alarm
.enabled
= 1;
427 rtc_set_alarm(alarm_rtc_dev
, &rtc_alarm
);
428 rtc_read_time(alarm_rtc_dev
, &rtc_current_rtc_time
);
429 rtc_tm_to_time(&rtc_current_rtc_time
, &rtc_current_time
);
431 "rtc alarm set at %ld, now %ld, rtc delta %ld.%09ld\n",
432 rtc_alarm_time
, rtc_current_time
,
433 rtc_delta
.tv_sec
, rtc_delta
.tv_nsec
);
434 if (rtc_current_time
+ 1 >= rtc_alarm_time
) {
435 pr_alarm(SUSPEND
, "alarm about to go off\n");
436 memset(&rtc_alarm
, 0, sizeof(rtc_alarm
));
437 rtc_alarm
.enabled
= 0;
438 rtc_set_alarm(alarm_rtc_dev
, &rtc_alarm
);
440 spin_lock_irqsave(&alarm_slock
, flags
);
442 wake_lock_timeout(&alarm_rtc_wake_lock
, 2 * HZ
);
443 update_timer_locked(&alarms
[ANDROID_ALARM_RTC_WAKEUP
],
445 update_timer_locked(&alarms
[
446 ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP
], false);
448 spin_unlock_irqrestore(&alarm_slock
, flags
);
454 static int alarm_resume(struct platform_device
*pdev
)
456 struct rtc_wkalrm alarm
;
459 pr_alarm(SUSPEND
, "alarm_resume(%p)\n", pdev
);
461 memset(&alarm
, 0, sizeof(alarm
));
463 rtc_set_alarm(alarm_rtc_dev
, &alarm
);
465 spin_lock_irqsave(&alarm_slock
, flags
);
467 update_timer_locked(&alarms
[ANDROID_ALARM_RTC_WAKEUP
], false);
468 update_timer_locked(&alarms
[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP
],
470 spin_unlock_irqrestore(&alarm_slock
, flags
);
475 static struct rtc_task alarm_rtc_task
= {
476 .func
= alarm_triggered_func
479 static int rtc_alarm_add_device(struct device
*dev
,
480 struct class_interface
*class_intf
)
483 struct rtc_device
*rtc
= to_rtc_device(dev
);
485 mutex_lock(&alarm_setrtc_mutex
);
493 platform_device_register_simple("alarm", -1, NULL
, 0);
494 if (IS_ERR(alarm_platform_dev
)) {
495 err
= PTR_ERR(alarm_platform_dev
);
498 err
= rtc_irq_register(rtc
, &alarm_rtc_task
);
502 pr_alarm(INIT_STATUS
, "using rtc device, %s, for alarms", rtc
->name
);
503 mutex_unlock(&alarm_setrtc_mutex
);
508 platform_device_unregister(alarm_platform_dev
);
511 mutex_unlock(&alarm_setrtc_mutex
);
515 static void rtc_alarm_remove_device(struct device
*dev
,
516 struct class_interface
*class_intf
)
518 if (dev
== &alarm_rtc_dev
->dev
) {
519 pr_alarm(INIT_STATUS
, "lost rtc device for alarms");
520 rtc_irq_unregister(alarm_rtc_dev
, &alarm_rtc_task
);
521 platform_device_unregister(alarm_platform_dev
);
522 alarm_rtc_dev
= NULL
;
526 static struct class_interface rtc_alarm_interface
= {
527 .add_dev
= &rtc_alarm_add_device
,
528 .remove_dev
= &rtc_alarm_remove_device
,
531 static struct platform_driver alarm_driver
= {
532 .suspend
= alarm_suspend
,
533 .resume
= alarm_resume
,
539 static int __init
alarm_late_init(void)
542 struct timespec tmp_time
, system_time
;
544 /* this needs to run after the rtc is read at boot */
545 spin_lock_irqsave(&alarm_slock
, flags
);
546 /* We read the current rtc and system time so we can later calulate
547 * elasped realtime to be (boot_systemtime + rtc - boot_rtc) ==
548 * (rtc - (boot_rtc - boot_systemtime))
550 getnstimeofday(&tmp_time
);
551 ktime_get_ts(&system_time
);
552 alarms
[ANDROID_ALARM_ELAPSED_REALTIME_WAKEUP
].delta
=
553 alarms
[ANDROID_ALARM_ELAPSED_REALTIME
].delta
=
554 timespec_to_ktime(timespec_sub(tmp_time
, system_time
));
556 spin_unlock_irqrestore(&alarm_slock
, flags
);
560 static int __init
alarm_driver_init(void)
565 for (i
= 0; i
< ANDROID_ALARM_SYSTEMTIME
; i
++) {
566 hrtimer_init(&alarms
[i
].timer
,
567 CLOCK_REALTIME
, HRTIMER_MODE_ABS
);
568 alarms
[i
].timer
.function
= alarm_timer_triggered
;
570 hrtimer_init(&alarms
[ANDROID_ALARM_SYSTEMTIME
].timer
,
571 CLOCK_MONOTONIC
, HRTIMER_MODE_ABS
);
572 alarms
[ANDROID_ALARM_SYSTEMTIME
].timer
.function
= alarm_timer_triggered
;
573 err
= platform_driver_register(&alarm_driver
);
576 wake_lock_init(&alarm_rtc_wake_lock
, WAKE_LOCK_SUSPEND
, "alarm_rtc");
577 rtc_alarm_interface
.class = rtc_class
;
578 err
= class_interface_register(&rtc_alarm_interface
);
585 wake_lock_destroy(&alarm_rtc_wake_lock
);
586 platform_driver_unregister(&alarm_driver
);
591 static void __exit
alarm_exit(void)
593 class_interface_unregister(&rtc_alarm_interface
);
594 wake_lock_destroy(&alarm_rtc_wake_lock
);
595 platform_driver_unregister(&alarm_driver
);
598 late_initcall(alarm_late_init
);
599 module_init(alarm_driver_init
);
600 module_exit(alarm_exit
);