2 * RTC subsystem, interface functions
4 * Copyright (C) 2005 Tower Technologies
5 * Author: Alessandro Zummo <a.zummo@towertech.it>
7 * based on arch/arm/common/rtctime.c
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #include <linux/rtc.h>
15 #include <linux/sched.h>
16 #include <linux/module.h>
17 #include <linux/log2.h>
18 #include <linux/workqueue.h>
20 static int rtc_timer_enqueue(struct rtc_device
*rtc
, struct rtc_timer
*timer
);
21 static void rtc_timer_remove(struct rtc_device
*rtc
, struct rtc_timer
*timer
);
23 static int __rtc_read_time(struct rtc_device
*rtc
, struct rtc_time
*tm
)
28 else if (!rtc
->ops
->read_time
)
31 memset(tm
, 0, sizeof(struct rtc_time
));
32 err
= rtc
->ops
->read_time(rtc
->dev
.parent
, tm
);
37 int rtc_read_time(struct rtc_device
*rtc
, struct rtc_time
*tm
)
41 err
= mutex_lock_interruptible(&rtc
->ops_lock
);
45 err
= __rtc_read_time(rtc
, tm
);
46 mutex_unlock(&rtc
->ops_lock
);
49 EXPORT_SYMBOL_GPL(rtc_read_time
);
51 int rtc_set_time(struct rtc_device
*rtc
, struct rtc_time
*tm
)
55 err
= rtc_valid_tm(tm
);
59 err
= mutex_lock_interruptible(&rtc
->ops_lock
);
65 else if (rtc
->ops
->set_time
)
66 err
= rtc
->ops
->set_time(rtc
->dev
.parent
, tm
);
67 else if (rtc
->ops
->set_mmss
) {
69 err
= rtc_tm_to_time(tm
, &secs
);
71 err
= rtc
->ops
->set_mmss(rtc
->dev
.parent
, secs
);
75 mutex_unlock(&rtc
->ops_lock
);
78 EXPORT_SYMBOL_GPL(rtc_set_time
);
80 int rtc_set_mmss(struct rtc_device
*rtc
, unsigned long secs
)
84 err
= mutex_lock_interruptible(&rtc
->ops_lock
);
90 else if (rtc
->ops
->set_mmss
)
91 err
= rtc
->ops
->set_mmss(rtc
->dev
.parent
, secs
);
92 else if (rtc
->ops
->read_time
&& rtc
->ops
->set_time
) {
93 struct rtc_time
new, old
;
95 err
= rtc
->ops
->read_time(rtc
->dev
.parent
, &old
);
97 rtc_time_to_tm(secs
, &new);
100 * avoid writing when we're going to change the day of
101 * the month. We will retry in the next minute. This
102 * basically means that if the RTC must not drift
103 * by more than 1 minute in 11 minutes.
105 if (!((old
.tm_hour
== 23 && old
.tm_min
== 59) ||
106 (new.tm_hour
== 23 && new.tm_min
== 59)))
107 err
= rtc
->ops
->set_time(rtc
->dev
.parent
,
114 mutex_unlock(&rtc
->ops_lock
);
118 EXPORT_SYMBOL_GPL(rtc_set_mmss
);
120 static int rtc_read_alarm_internal(struct rtc_device
*rtc
, struct rtc_wkalrm
*alarm
)
124 err
= mutex_lock_interruptible(&rtc
->ops_lock
);
128 if (rtc
->ops
== NULL
)
130 else if (!rtc
->ops
->read_alarm
)
133 memset(alarm
, 0, sizeof(struct rtc_wkalrm
));
134 err
= rtc
->ops
->read_alarm(rtc
->dev
.parent
, alarm
);
137 mutex_unlock(&rtc
->ops_lock
);
141 int __rtc_read_alarm(struct rtc_device
*rtc
, struct rtc_wkalrm
*alarm
)
144 struct rtc_time before
, now
;
146 unsigned long t_now
, t_alm
;
147 enum { none
, day
, month
, year
} missing
= none
;
150 /* The lower level RTC driver may return -1 in some fields,
151 * creating invalid alarm->time values, for reasons like:
153 * - The hardware may not be capable of filling them in;
154 * many alarms match only on time-of-day fields, not
155 * day/month/year calendar data.
157 * - Some hardware uses illegal values as "wildcard" match
158 * values, which non-Linux firmware (like a BIOS) may try
159 * to set up as e.g. "alarm 15 minutes after each hour".
160 * Linux uses only oneshot alarms.
162 * When we see that here, we deal with it by using values from
163 * a current RTC timestamp for any missing (-1) values. The
164 * RTC driver prevents "periodic alarm" modes.
166 * But this can be racey, because some fields of the RTC timestamp
167 * may have wrapped in the interval since we read the RTC alarm,
168 * which would lead to us inserting inconsistent values in place
171 * Reading the alarm and timestamp in the reverse sequence
172 * would have the same race condition, and not solve the issue.
174 * So, we must first read the RTC timestamp,
175 * then read the RTC alarm value,
176 * and then read a second RTC timestamp.
178 * If any fields of the second timestamp have changed
179 * when compared with the first timestamp, then we know
180 * our timestamp may be inconsistent with that used by
181 * the low-level rtc_read_alarm_internal() function.
183 * So, when the two timestamps disagree, we just loop and do
184 * the process again to get a fully consistent set of values.
186 * This could all instead be done in the lower level driver,
187 * but since more than one lower level RTC implementation needs it,
188 * then it's probably best best to do it here instead of there..
191 /* Get the "before" timestamp */
192 err
= rtc_read_time(rtc
, &before
);
197 memcpy(&before
, &now
, sizeof(struct rtc_time
));
200 /* get the RTC alarm values, which may be incomplete */
201 err
= rtc_read_alarm_internal(rtc
, alarm
);
205 /* full-function RTCs won't have such missing fields */
206 if (rtc_valid_tm(&alarm
->time
) == 0)
209 /* get the "after" timestamp, to detect wrapped fields */
210 err
= rtc_read_time(rtc
, &now
);
214 /* note that tm_sec is a "don't care" value here: */
215 } while ( before
.tm_min
!= now
.tm_min
216 || before
.tm_hour
!= now
.tm_hour
217 || before
.tm_mon
!= now
.tm_mon
218 || before
.tm_year
!= now
.tm_year
);
220 /* Fill in the missing alarm fields using the timestamp; we
221 * know there's at least one since alarm->time is invalid.
223 if (alarm
->time
.tm_sec
== -1)
224 alarm
->time
.tm_sec
= now
.tm_sec
;
225 if (alarm
->time
.tm_min
== -1)
226 alarm
->time
.tm_min
= now
.tm_min
;
227 if (alarm
->time
.tm_hour
== -1)
228 alarm
->time
.tm_hour
= now
.tm_hour
;
230 /* For simplicity, only support date rollover for now */
231 if (alarm
->time
.tm_mday
== -1) {
232 alarm
->time
.tm_mday
= now
.tm_mday
;
235 if (alarm
->time
.tm_mon
== -1) {
236 alarm
->time
.tm_mon
= now
.tm_mon
;
240 if (alarm
->time
.tm_year
== -1) {
241 alarm
->time
.tm_year
= now
.tm_year
;
246 /* with luck, no rollover is needed */
247 rtc_tm_to_time(&now
, &t_now
);
248 rtc_tm_to_time(&alarm
->time
, &t_alm
);
254 /* 24 hour rollover ... if it's now 10am Monday, an alarm that
255 * that will trigger at 5am will do so at 5am Tuesday, which
256 * could also be in the next month or year. This is a common
257 * case, especially for PCs.
260 dev_dbg(&rtc
->dev
, "alarm rollover: %s\n", "day");
261 t_alm
+= 24 * 60 * 60;
262 rtc_time_to_tm(t_alm
, &alarm
->time
);
265 /* Month rollover ... if it's the 31th, an alarm on the 3rd will
266 * be next month. An alarm matching on the 30th, 29th, or 28th
267 * may end up in the month after that! Many newer PCs support
268 * this type of alarm.
271 dev_dbg(&rtc
->dev
, "alarm rollover: %s\n", "month");
273 if (alarm
->time
.tm_mon
< 11)
274 alarm
->time
.tm_mon
++;
276 alarm
->time
.tm_mon
= 0;
277 alarm
->time
.tm_year
++;
279 days
= rtc_month_days(alarm
->time
.tm_mon
,
280 alarm
->time
.tm_year
);
281 } while (days
< alarm
->time
.tm_mday
);
284 /* Year rollover ... easy except for leap years! */
286 dev_dbg(&rtc
->dev
, "alarm rollover: %s\n", "year");
288 alarm
->time
.tm_year
++;
289 } while (rtc_valid_tm(&alarm
->time
) != 0);
293 dev_warn(&rtc
->dev
, "alarm rollover not handled\n");
300 int rtc_read_alarm(struct rtc_device
*rtc
, struct rtc_wkalrm
*alarm
)
304 err
= mutex_lock_interruptible(&rtc
->ops_lock
);
307 if (rtc
->ops
== NULL
)
309 else if (!rtc
->ops
->read_alarm
)
312 memset(alarm
, 0, sizeof(struct rtc_wkalrm
));
313 alarm
->enabled
= rtc
->aie_timer
.enabled
;
314 alarm
->time
= rtc_ktime_to_tm(rtc
->aie_timer
.node
.expires
);
316 mutex_unlock(&rtc
->ops_lock
);
320 EXPORT_SYMBOL_GPL(rtc_read_alarm
);
322 static int __rtc_set_alarm(struct rtc_device
*rtc
, struct rtc_wkalrm
*alarm
)
328 err
= rtc_valid_tm(&alarm
->time
);
331 rtc_tm_to_time(&alarm
->time
, &scheduled
);
333 /* Make sure we're not setting alarms in the past */
334 err
= __rtc_read_time(rtc
, &tm
);
335 rtc_tm_to_time(&tm
, &now
);
336 if (scheduled
<= now
)
339 * XXX - We just checked to make sure the alarm time is not
340 * in the past, but there is still a race window where if
341 * the is alarm set for the next second and the second ticks
342 * over right here, before we set the alarm.
347 else if (!rtc
->ops
->set_alarm
)
350 err
= rtc
->ops
->set_alarm(rtc
->dev
.parent
, alarm
);
355 int rtc_set_alarm(struct rtc_device
*rtc
, struct rtc_wkalrm
*alarm
)
359 err
= rtc_valid_tm(&alarm
->time
);
363 err
= mutex_lock_interruptible(&rtc
->ops_lock
);
366 if (rtc
->aie_timer
.enabled
) {
367 rtc_timer_remove(rtc
, &rtc
->aie_timer
);
369 rtc
->aie_timer
.node
.expires
= rtc_tm_to_ktime(alarm
->time
);
370 rtc
->aie_timer
.period
= ktime_set(0, 0);
371 if (alarm
->enabled
) {
372 err
= rtc_timer_enqueue(rtc
, &rtc
->aie_timer
);
374 mutex_unlock(&rtc
->ops_lock
);
377 EXPORT_SYMBOL_GPL(rtc_set_alarm
);
379 /* Called once per device from rtc_device_register */
380 int rtc_initialize_alarm(struct rtc_device
*rtc
, struct rtc_wkalrm
*alarm
)
384 err
= rtc_valid_tm(&alarm
->time
);
388 err
= mutex_lock_interruptible(&rtc
->ops_lock
);
392 rtc
->aie_timer
.node
.expires
= rtc_tm_to_ktime(alarm
->time
);
393 rtc
->aie_timer
.period
= ktime_set(0, 0);
394 if (alarm
->enabled
) {
395 rtc
->aie_timer
.enabled
= 1;
396 timerqueue_add(&rtc
->timerqueue
, &rtc
->aie_timer
.node
);
398 mutex_unlock(&rtc
->ops_lock
);
401 EXPORT_SYMBOL_GPL(rtc_initialize_alarm
);
405 int rtc_alarm_irq_enable(struct rtc_device
*rtc
, unsigned int enabled
)
407 int err
= mutex_lock_interruptible(&rtc
->ops_lock
);
411 if (rtc
->aie_timer
.enabled
!= enabled
) {
413 err
= rtc_timer_enqueue(rtc
, &rtc
->aie_timer
);
415 rtc_timer_remove(rtc
, &rtc
->aie_timer
);
422 else if (!rtc
->ops
->alarm_irq_enable
)
425 err
= rtc
->ops
->alarm_irq_enable(rtc
->dev
.parent
, enabled
);
427 mutex_unlock(&rtc
->ops_lock
);
430 EXPORT_SYMBOL_GPL(rtc_alarm_irq_enable
);
432 int rtc_update_irq_enable(struct rtc_device
*rtc
, unsigned int enabled
)
434 int err
= mutex_lock_interruptible(&rtc
->ops_lock
);
438 #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
439 if (enabled
== 0 && rtc
->uie_irq_active
) {
440 mutex_unlock(&rtc
->ops_lock
);
441 return rtc_dev_update_irq_enable_emul(rtc
, 0);
444 /* make sure we're changing state */
445 if (rtc
->uie_rtctimer
.enabled
== enabled
)
452 __rtc_read_time(rtc
, &tm
);
453 onesec
= ktime_set(1, 0);
454 now
= rtc_tm_to_ktime(tm
);
455 rtc
->uie_rtctimer
.node
.expires
= ktime_add(now
, onesec
);
456 rtc
->uie_rtctimer
.period
= ktime_set(1, 0);
457 err
= rtc_timer_enqueue(rtc
, &rtc
->uie_rtctimer
);
459 rtc_timer_remove(rtc
, &rtc
->uie_rtctimer
);
462 mutex_unlock(&rtc
->ops_lock
);
463 #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
465 * Enable emulation if the driver did not provide
466 * the update_irq_enable function pointer or if returned
467 * -EINVAL to signal that it has been configured without
468 * interrupts or that are not available at the moment.
471 err
= rtc_dev_update_irq_enable_emul(rtc
, enabled
);
476 EXPORT_SYMBOL_GPL(rtc_update_irq_enable
);
480 * rtc_handle_legacy_irq - AIE, UIE and PIE event hook
481 * @rtc: pointer to the rtc device
483 * This function is called when an AIE, UIE or PIE mode interrupt
484 * has occurred (or been emulated).
486 * Triggers the registered irq_task function callback.
488 void rtc_handle_legacy_irq(struct rtc_device
*rtc
, int num
, int mode
)
492 /* mark one irq of the appropriate mode */
493 spin_lock_irqsave(&rtc
->irq_lock
, flags
);
494 rtc
->irq_data
= (rtc
->irq_data
+ (num
<< 8)) | (RTC_IRQF
|mode
);
495 spin_unlock_irqrestore(&rtc
->irq_lock
, flags
);
497 /* call the task func */
498 spin_lock_irqsave(&rtc
->irq_task_lock
, flags
);
500 rtc
->irq_task
->func(rtc
->irq_task
->private_data
);
501 spin_unlock_irqrestore(&rtc
->irq_task_lock
, flags
);
503 wake_up_interruptible(&rtc
->irq_queue
);
504 kill_fasync(&rtc
->async_queue
, SIGIO
, POLL_IN
);
509 * rtc_aie_update_irq - AIE mode rtctimer hook
510 * @private: pointer to the rtc_device
512 * This functions is called when the aie_timer expires.
514 void rtc_aie_update_irq(void *private)
516 struct rtc_device
*rtc
= (struct rtc_device
*)private;
517 rtc_handle_legacy_irq(rtc
, 1, RTC_AF
);
522 * rtc_uie_update_irq - UIE mode rtctimer hook
523 * @private: pointer to the rtc_device
525 * This functions is called when the uie_timer expires.
527 void rtc_uie_update_irq(void *private)
529 struct rtc_device
*rtc
= (struct rtc_device
*)private;
530 rtc_handle_legacy_irq(rtc
, 1, RTC_UF
);
535 * rtc_pie_update_irq - PIE mode hrtimer hook
536 * @timer: pointer to the pie mode hrtimer
538 * This function is used to emulate PIE mode interrupts
539 * using an hrtimer. This function is called when the periodic
542 enum hrtimer_restart
rtc_pie_update_irq(struct hrtimer
*timer
)
544 struct rtc_device
*rtc
;
547 rtc
= container_of(timer
, struct rtc_device
, pie_timer
);
549 period
= ktime_set(0, NSEC_PER_SEC
/rtc
->irq_freq
);
550 count
= hrtimer_forward_now(timer
, period
);
552 rtc_handle_legacy_irq(rtc
, count
, RTC_PF
);
554 return HRTIMER_RESTART
;
558 * rtc_update_irq - Triggered when a RTC interrupt occurs.
559 * @rtc: the rtc device
560 * @num: how many irqs are being reported (usually one)
561 * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
564 void rtc_update_irq(struct rtc_device
*rtc
,
565 unsigned long num
, unsigned long events
)
567 schedule_work(&rtc
->irqwork
);
569 EXPORT_SYMBOL_GPL(rtc_update_irq
);
571 static int __rtc_match(struct device
*dev
, void *data
)
573 char *name
= (char *)data
;
575 if (strcmp(dev_name(dev
), name
) == 0)
580 struct rtc_device
*rtc_class_open(char *name
)
583 struct rtc_device
*rtc
= NULL
;
585 dev
= class_find_device(rtc_class
, NULL
, name
, __rtc_match
);
587 rtc
= to_rtc_device(dev
);
590 if (!try_module_get(rtc
->owner
)) {
598 EXPORT_SYMBOL_GPL(rtc_class_open
);
600 void rtc_class_close(struct rtc_device
*rtc
)
602 module_put(rtc
->owner
);
603 put_device(&rtc
->dev
);
605 EXPORT_SYMBOL_GPL(rtc_class_close
);
607 int rtc_irq_register(struct rtc_device
*rtc
, struct rtc_task
*task
)
611 if (task
== NULL
|| task
->func
== NULL
)
614 /* Cannot register while the char dev is in use */
615 if (test_and_set_bit_lock(RTC_DEV_BUSY
, &rtc
->flags
))
618 spin_lock_irq(&rtc
->irq_task_lock
);
619 if (rtc
->irq_task
== NULL
) {
620 rtc
->irq_task
= task
;
623 spin_unlock_irq(&rtc
->irq_task_lock
);
625 clear_bit_unlock(RTC_DEV_BUSY
, &rtc
->flags
);
629 EXPORT_SYMBOL_GPL(rtc_irq_register
);
631 void rtc_irq_unregister(struct rtc_device
*rtc
, struct rtc_task
*task
)
633 spin_lock_irq(&rtc
->irq_task_lock
);
634 if (rtc
->irq_task
== task
)
635 rtc
->irq_task
= NULL
;
636 spin_unlock_irq(&rtc
->irq_task_lock
);
638 EXPORT_SYMBOL_GPL(rtc_irq_unregister
);
640 static int rtc_update_hrtimer(struct rtc_device
*rtc
, int enabled
)
643 * We unconditionally cancel the timer here, because otherwise
644 * we could run into BUG_ON(timer->state != HRTIMER_STATE_CALLBACK);
645 * when we manage to start the timer before the callback
646 * returns HRTIMER_RESTART.
648 * We cannot use hrtimer_cancel() here as a running callback
649 * could be blocked on rtc->irq_task_lock and hrtimer_cancel()
650 * would spin forever.
652 if (hrtimer_try_to_cancel(&rtc
->pie_timer
) < 0)
656 ktime_t period
= ktime_set(0, NSEC_PER_SEC
/ rtc
->irq_freq
);
658 hrtimer_start(&rtc
->pie_timer
, period
, HRTIMER_MODE_REL
);
664 * rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs
665 * @rtc: the rtc device
666 * @task: currently registered with rtc_irq_register()
667 * @enabled: true to enable periodic IRQs
670 * Note that rtc_irq_set_freq() should previously have been used to
671 * specify the desired frequency of periodic IRQ task->func() callbacks.
673 int rtc_irq_set_state(struct rtc_device
*rtc
, struct rtc_task
*task
, int enabled
)
679 spin_lock_irqsave(&rtc
->irq_task_lock
, flags
);
680 if (rtc
->irq_task
!= NULL
&& task
== NULL
)
682 if (rtc
->irq_task
!= task
)
685 if (rtc_update_hrtimer(rtc
, enabled
) < 0) {
686 spin_unlock_irqrestore(&rtc
->irq_task_lock
, flags
);
690 rtc
->pie_enabled
= enabled
;
692 spin_unlock_irqrestore(&rtc
->irq_task_lock
, flags
);
695 EXPORT_SYMBOL_GPL(rtc_irq_set_state
);
698 * rtc_irq_set_freq - set 2^N Hz periodic IRQ frequency for IRQ
699 * @rtc: the rtc device
700 * @task: currently registered with rtc_irq_register()
701 * @freq: positive frequency with which task->func() will be called
704 * Note that rtc_irq_set_state() is used to enable or disable the
707 int rtc_irq_set_freq(struct rtc_device
*rtc
, struct rtc_task
*task
, int freq
)
712 if (freq
<= 0 || freq
> 5000)
715 spin_lock_irqsave(&rtc
->irq_task_lock
, flags
);
716 if (rtc
->irq_task
!= NULL
&& task
== NULL
)
718 if (rtc
->irq_task
!= task
)
721 rtc
->irq_freq
= freq
;
722 if (rtc
->pie_enabled
&& rtc_update_hrtimer(rtc
, 1) < 0) {
723 spin_unlock_irqrestore(&rtc
->irq_task_lock
, flags
);
728 spin_unlock_irqrestore(&rtc
->irq_task_lock
, flags
);
731 EXPORT_SYMBOL_GPL(rtc_irq_set_freq
);
734 * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue
736 * @timer timer being added.
738 * Enqueues a timer onto the rtc devices timerqueue and sets
739 * the next alarm event appropriately.
741 * Sets the enabled bit on the added timer.
743 * Must hold ops_lock for proper serialization of timerqueue
745 static int rtc_timer_enqueue(struct rtc_device
*rtc
, struct rtc_timer
*timer
)
748 timerqueue_add(&rtc
->timerqueue
, &timer
->node
);
749 if (&timer
->node
== timerqueue_getnext(&rtc
->timerqueue
)) {
750 struct rtc_wkalrm alarm
;
752 alarm
.time
= rtc_ktime_to_tm(timer
->node
.expires
);
754 err
= __rtc_set_alarm(rtc
, &alarm
);
756 schedule_work(&rtc
->irqwork
);
758 timerqueue_del(&rtc
->timerqueue
, &timer
->node
);
767 * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue
769 * @timer timer being removed.
771 * Removes a timer onto the rtc devices timerqueue and sets
772 * the next alarm event appropriately.
774 * Clears the enabled bit on the removed timer.
776 * Must hold ops_lock for proper serialization of timerqueue
778 static void rtc_timer_remove(struct rtc_device
*rtc
, struct rtc_timer
*timer
)
780 struct timerqueue_node
*next
= timerqueue_getnext(&rtc
->timerqueue
);
781 timerqueue_del(&rtc
->timerqueue
, &timer
->node
);
783 if (next
== &timer
->node
) {
784 struct rtc_wkalrm alarm
;
786 next
= timerqueue_getnext(&rtc
->timerqueue
);
789 alarm
.time
= rtc_ktime_to_tm(next
->expires
);
791 err
= __rtc_set_alarm(rtc
, &alarm
);
793 schedule_work(&rtc
->irqwork
);
798 * rtc_timer_do_work - Expires rtc timers
800 * @timer timer being removed.
802 * Expires rtc timers. Reprograms next alarm event if needed.
803 * Called via worktask.
805 * Serializes access to timerqueue via ops_lock mutex
807 void rtc_timer_do_work(struct work_struct
*work
)
809 struct rtc_timer
*timer
;
810 struct timerqueue_node
*next
;
814 struct rtc_device
*rtc
=
815 container_of(work
, struct rtc_device
, irqwork
);
817 mutex_lock(&rtc
->ops_lock
);
819 __rtc_read_time(rtc
, &tm
);
820 now
= rtc_tm_to_ktime(tm
);
821 while ((next
= timerqueue_getnext(&rtc
->timerqueue
))) {
822 if (next
->expires
.tv64
> now
.tv64
)
826 timer
= container_of(next
, struct rtc_timer
, node
);
827 timerqueue_del(&rtc
->timerqueue
, &timer
->node
);
829 if (timer
->task
.func
)
830 timer
->task
.func(timer
->task
.private_data
);
832 /* Re-add/fwd periodic timers */
833 if (ktime_to_ns(timer
->period
)) {
834 timer
->node
.expires
= ktime_add(timer
->node
.expires
,
837 timerqueue_add(&rtc
->timerqueue
, &timer
->node
);
843 struct rtc_wkalrm alarm
;
845 alarm
.time
= rtc_ktime_to_tm(next
->expires
);
847 err
= __rtc_set_alarm(rtc
, &alarm
);
852 mutex_unlock(&rtc
->ops_lock
);
856 /* rtc_timer_init - Initializes an rtc_timer
857 * @timer: timer to be intiialized
858 * @f: function pointer to be called when timer fires
859 * @data: private data passed to function pointer
861 * Kernel interface to initializing an rtc_timer.
863 void rtc_timer_init(struct rtc_timer
*timer
, void (*f
)(void* p
), void* data
)
865 timerqueue_init(&timer
->node
);
867 timer
->task
.func
= f
;
868 timer
->task
.private_data
= data
;
871 /* rtc_timer_start - Sets an rtc_timer to fire in the future
872 * @ rtc: rtc device to be used
873 * @ timer: timer being set
874 * @ expires: time at which to expire the timer
875 * @ period: period that the timer will recur
877 * Kernel interface to set an rtc_timer
879 int rtc_timer_start(struct rtc_device
*rtc
, struct rtc_timer
* timer
,
880 ktime_t expires
, ktime_t period
)
883 mutex_lock(&rtc
->ops_lock
);
885 rtc_timer_remove(rtc
, timer
);
887 timer
->node
.expires
= expires
;
888 timer
->period
= period
;
890 ret
= rtc_timer_enqueue(rtc
, timer
);
892 mutex_unlock(&rtc
->ops_lock
);
896 /* rtc_timer_cancel - Stops an rtc_timer
897 * @ rtc: rtc device to be used
898 * @ timer: timer being set
900 * Kernel interface to cancel an rtc_timer
902 int rtc_timer_cancel(struct rtc_device
*rtc
, struct rtc_timer
* timer
)
905 mutex_lock(&rtc
->ops_lock
);
907 rtc_timer_remove(rtc
, timer
);
908 mutex_unlock(&rtc
->ops_lock
);