From bd729d72b428261f2975360e0c117d7d7a2cd6e8 Mon Sep 17 00:00:00 2001 From: John Stultz Date: Thu, 5 Jan 2012 15:21:19 -0800 Subject: rtc: Avoid setting alarm to a time in the past In some cases at boot up, the RTC alarm may be set in the past, but still have the enabled flag on. This was causing problems, because we would then enqueue the alarm into the timerqueue, but it would never fire. This would clog up the timerqueue and keep other alarms from working. The fix is to check the alarm against the current rtc time at boot and avoid enqueueing the alarm if it is in the past. Reported-by: NeilBrown Tested-by: NeilBrown Tested-by: Sander Eikelenboom Signed-off-by: John Stultz --- drivers/rtc/interface.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'drivers/rtc/interface.c') diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index 8a1c031391d..c55a16041b6 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -380,18 +380,27 @@ EXPORT_SYMBOL_GPL(rtc_set_alarm); int rtc_initialize_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) { int err; + struct rtc_time now; err = rtc_valid_tm(&alarm->time); if (err != 0) return err; + err = rtc_read_time(rtc, &now); + if (err) + return err; + err = mutex_lock_interruptible(&rtc->ops_lock); if (err) return err; rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time); rtc->aie_timer.period = ktime_set(0, 0); - if (alarm->enabled) { + + /* Alarm has to be enabled & in the futrure for us to enqueue it */ + if (alarm->enabled && (rtc_tm_to_ktime(now).tv64 < + rtc->aie_timer.node.expires.tv64)) { + rtc->aie_timer.enabled = 1; timerqueue_add(&rtc->timerqueue, &rtc->aie_timer.node); } -- cgit v1.2.3-70-g09d2 From 5f9679d29c7959445d4af1eb85ee55e4ebad4a93 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Fri, 9 Dec 2011 09:39:15 +1100 Subject: 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 Signed-off-by: NeilBrown [Remove problematic initialization change, update commit log, also catch set_mmss case -jstultz] Signed-off-by: John Stultz --- drivers/rtc/interface.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/rtc/interface.c') diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index c55a16041b6..167e68a9ffd 100644 --- 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; } -- cgit v1.2.3-70-g09d2 From 41c7f7424259ff11009449f87c95656f69f9b186 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Tue, 22 Nov 2011 11:03:14 +0100 Subject: rtc: Disable the alarm in the hardware (v2) Currently, the RTC code does not disable the alarm in the hardware. This means that after a sequence such as the one below (the files are in the RTC sysfs), the box will boot up after 2 minutes even though we've asked for the alarm to be turned off. # echo $((`cat since_epoch`)+120) > wakealarm # echo 0 > wakealarm # poweroff Fix this by disabling the alarm when there are no timers to run. The original version of this patch was reverted. This version disables the irq directly instead of setting a disabled timer in the future. Cc: stable@kernel.org Cc: John Stultz Signed-off-by: Rabin Vincent [Merged in the second revision from Rabin] Signed-off-by: John Stultz --- drivers/rtc/interface.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'drivers/rtc/interface.c') diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index 167e68a9ffd..dc87eda6581 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -776,6 +776,14 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) return 0; } +static void rtc_alarm_disable(struct rtc_device *rtc) +{ + if (!rtc->ops || !rtc->ops->alarm_irq_enable) + return; + + rtc->ops->alarm_irq_enable(rtc->dev.parent, false); +} + /** * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue * @rtc rtc device @@ -797,8 +805,10 @@ static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer) struct rtc_wkalrm alarm; int err; next = timerqueue_getnext(&rtc->timerqueue); - if (!next) + if (!next) { + rtc_alarm_disable(rtc); return; + } alarm.time = rtc_ktime_to_tm(next->expires); alarm.enabled = 1; err = __rtc_set_alarm(rtc, &alarm); @@ -860,7 +870,8 @@ again: err = __rtc_set_alarm(rtc, &alarm); if (err == -ETIME) goto again; - } + } else + rtc_alarm_disable(rtc); mutex_unlock(&rtc->ops_lock); } -- cgit v1.2.3-70-g09d2 From 4a649903f91232d02284d53724b0a45728111767 Mon Sep 17 00:00:00 2001 From: John Stultz Date: Tue, 6 Mar 2012 17:16:09 -0800 Subject: rtc: Provide flag for rtc devices that don't support UIE Richard Weinberger noticed that on some RTC hardware that doesn't support UIE mode, due to coarse granular alarms (like 1minute resolution), the current virtualized RTC support doesn't properly error out when UIE is enabled. Instead the current code queues an alarm for the next second, but it won't fire until up to a miniute later. This patch provides a generic way to flag this sort of hardware and fixes the issue on the mpc5121 where Richard noticed the problem. CC: stable@vger.kernel.org Reported-by: Richard Weinberger Tested-by: Richard Weinberger Signed-off-by: John Stultz --- drivers/rtc/interface.c | 5 +++++ drivers/rtc/rtc-mpc5121.c | 2 ++ include/linux/rtc.h | 3 ++- 3 files changed, 9 insertions(+), 1 deletion(-) (limited to 'drivers/rtc/interface.c') diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index dc87eda6581..eb415bd7649 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -458,6 +458,11 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled) if (rtc->uie_rtctimer.enabled == enabled) goto out; + if (rtc->uie_unsupported) { + err = -EINVAL; + goto out; + } + if (enabled) { struct rtc_time tm; ktime_t now, onesec; diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c index 9d3caccfc25..613447abdbe 100644 --- a/drivers/rtc/rtc-mpc5121.c +++ b/drivers/rtc/rtc-mpc5121.c @@ -360,6 +360,8 @@ static int __devinit mpc5121_rtc_probe(struct platform_device *op) &mpc5200_rtc_ops, THIS_MODULE); } + rtc->rtc->uie_unsupported = 1; + if (IS_ERR(rtc->rtc)) { err = PTR_ERR(rtc->rtc); goto out_free_irq; diff --git a/include/linux/rtc.h b/include/linux/rtc.h index 93f4d035076..fcabfb4873c 100644 --- a/include/linux/rtc.h +++ b/include/linux/rtc.h @@ -202,7 +202,8 @@ struct rtc_device struct hrtimer pie_timer; /* sub second exp, so needs hrtimer */ int pie_enabled; struct work_struct irqwork; - + /* Some hardware can't support UIE mode */ + int uie_unsupported; #ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL struct work_struct uie_task; -- cgit v1.2.3-70-g09d2