rtc: Expire alarms after the time is set. (v2)

If the alarm time programming in the rtc is ever in the past, it won't fire,
and any other alarm will be queued after it so they won't fire either.

So any time that the alarm might be in the past, we need to trigger
the irq handler to ensure the old alarm is cleared and the timer queue
is fully in the future.

This is done whenever the RTC clock is set.

This is the second revision of this patch, which was earlier reverted.
This version avoids the initialization problem, which is handled by
a different patch.

Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: NeilBrown <neilb@suse.de>
[Remove problematic initialization change, update commit log, also
catch set_mmss case -jstultz]
Signed-off-by: John Stultz <john.stultz@linaro.org>

diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index c55a16041b6ec08c62ae07834ca39d2d6140f508..167e68a9ffdad5c7e37c691f2d7b99c865fe6d20 100644 (file)
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -73,6 +73,8 @@ int rtc_set_time(struct rtc_device *rtc, struct rtc_time *tm)
                err = -EINVAL;
 
        mutex_unlock(&rtc->ops_lock);
+       /* A timer might have just expired */
+       schedule_work(&rtc->irqwork);
        return err;
 }
 EXPORT_SYMBOL_GPL(rtc_set_time);
@@ -112,6 +114,8 @@ int rtc_set_mmss(struct rtc_device *rtc, unsigned long secs)
                err = -EINVAL;
 
        mutex_unlock(&rtc->ops_lock);
+       /* A timer might have just expired */
+       schedule_work(&rtc->irqwork);
 
        return err;
 }