From c0afabd3d553c521e003779c127143ffde55a16f 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 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. Cc: stable@kernel.org Cc: John Stultz Signed-off-by: Rabin Vincent Signed-off-by: John Stultz --- drivers/rtc/interface.c | 44 ++++++++++++++++++++++++++++++++++---------- 1 file changed, 34 insertions(+), 10 deletions(-) diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index 3195dbd3ec3468..e3cf2f54221fc6 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -318,6 +318,20 @@ int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) } EXPORT_SYMBOL_GPL(rtc_read_alarm); +static int ___rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) +{ + int err; + + if (!rtc->ops) + err = -ENODEV; + else if (!rtc->ops->set_alarm) + err = -EINVAL; + else + err = rtc->ops->set_alarm(rtc->dev.parent, alarm); + + return err; +} + static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) { struct rtc_time tm; @@ -341,14 +355,7 @@ static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) * over right here, before we set the alarm. */ - if (!rtc->ops) - err = -ENODEV; - else if (!rtc->ops->set_alarm) - err = -EINVAL; - else - err = rtc->ops->set_alarm(rtc->dev.parent, alarm); - - return err; + return ___rtc_set_alarm(rtc, alarm); } int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) @@ -762,6 +769,20 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) return 0; } +static void rtc_alarm_disable(struct rtc_device *rtc) +{ + struct rtc_wkalrm alarm; + struct rtc_time tm; + + __rtc_read_time(rtc, &tm); + + alarm.time = rtc_ktime_to_tm(ktime_add(rtc_tm_to_ktime(tm), + ktime_set(300, 0))); + alarm.enabled = 0; + + ___rtc_set_alarm(rtc, &alarm); +} + /** * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue * @rtc rtc device @@ -783,8 +804,10 @@ 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); @@ -846,7 +869,8 @@ again: err = __rtc_set_alarm(rtc, &alarm); if (err == -ETIME) goto again; - } + } else + rtc_alarm_disable(rtc); mutex_unlock(&rtc->ops_lock); } -- cgit 1.2.3-korg From 6a8943d9ec2567572fca25cf69ad45844d0141a3 Mon Sep 17 00:00:00 2001 From: Arve Hjønnevåg Date: Tue, 22 Nov 2011 18:24:51 -0800 Subject: rtc: Fix some bugs that allowed accumulating time drift in suspend/resume MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The current code checks if abs(delta_delta.tv_sec) is greater or equal to two before it discards the old delta value, but this can trigger at close to -1 seconds since -1.000000001 seconds is stored as tv_sec -2 and tv_nsec 999999999 in a normalized timespec. rtc_resume had an early return check if the rtc value had not changed since rtc_suspend. This effectivly stops time for the duration of the short sleep. Check if sleep_time is positive after all the adjustments have been applied instead since this allows the old_system adjustment in rtc_suspend to have an effect even for short sleep cycles. CC: stable@kernel.org Signed-off-by: Arve Hjønnevåg Signed-off-by: John Stultz --- drivers/rtc/class.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index 01a7df5317c1bd..b82a1554cdc1b1 100644 --- a/drivers/rtc/class.c +++ b/drivers/rtc/class.c @@ -66,7 +66,7 @@ static int rtc_suspend(struct device *dev, pm_message_t mesg) */ delta = timespec_sub(old_system, old_rtc); delta_delta = timespec_sub(delta, old_delta); - if (abs(delta_delta.tv_sec) >= 2) { + if (delta_delta.tv_sec < -2 || delta_delta.tv_sec >= 2) { /* * if delta_delta is too large, assume time correction * has occured and set old_delta to the current delta. @@ -100,9 +100,8 @@ static int rtc_resume(struct device *dev) rtc_tm_to_time(&tm, &new_rtc.tv_sec); new_rtc.tv_nsec = 0; - if (new_rtc.tv_sec <= old_rtc.tv_sec) { - if (new_rtc.tv_sec < old_rtc.tv_sec) - pr_debug("%s: time travel!\n", dev_name(&rtc->dev)); + if (new_rtc.tv_sec < old_rtc.tv_sec) { + pr_debug("%s: time travel!\n", dev_name(&rtc->dev)); return 0; } @@ -119,7 +118,8 @@ static int rtc_resume(struct device *dev) sleep_time = timespec_sub(sleep_time, timespec_sub(new_system, old_system)); - timekeeping_inject_sleeptime(&sleep_time); + if (sleep_time.tv_sec >= 0) + timekeeping_inject_sleeptime(&sleep_time); return 0; } -- cgit 1.2.3-korg From b1f919664d04a8d0ba29cb76673c7ca3325a2006 Mon Sep 17 00:00:00 2001 From: "Yang Honggang (Joseph)" Date: Thu, 1 Dec 2011 22:22:41 -0500 Subject: clocksource: Fix bug with max_deferment margin calculation In order to leave a margin of 12.5% we should >> 3 not >> 5. CC: stable@kernel.org Signed-off-by: Yang Honggang (Joseph) [jstultz: Modified commit subject] Signed-off-by: John Stultz --- kernel/time/clocksource.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index cfc65e1eb9fbba..da2f760e780c9c 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -548,7 +548,7 @@ static u64 clocksource_max_deferment(struct clocksource *cs) * note a margin of 12.5% is used because this can be computed with * a shift, versus say 10% which would require division. */ - return max_nsecs - (max_nsecs >> 5); + return max_nsecs - (max_nsecs >> 3); } #ifndef CONFIG_ARCH_USES_GETTIMEOFFSET @@ -669,7 +669,7 @@ void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq) * ~ 0.06ppm granularity for NTP. We apply the same 12.5% * margin as we do in clocksource_max_deferment() */ - sec = (cs->mask - (cs->mask >> 5)); + sec = (cs->mask - (cs->mask >> 3)); do_div(sec, freq); do_div(sec, scale); if (!sec) -- cgit 1.2.3-korg From c1be84309c58b1e7c6d626e28fba41a22b364c3d Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 2 Dec 2011 12:34:16 +0100 Subject: tick-broadcast: Stop active broadcast device when replacing it When a better rated broadcast device is installed, then the current active device is not disabled, which results in two running broadcast devices. Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org --- kernel/time/tick-broadcast.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index f954282d9a8275..fd4a7b1625a20b 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -71,7 +71,7 @@ int tick_check_broadcast_device(struct clock_event_device *dev) (dev->features & CLOCK_EVT_FEAT_C3STOP)) return 0; - clockevents_exchange_device(NULL, dev); + clockevents_exchange_device(tick_broadcast_device.evtdev, dev); tick_broadcast_device.evtdev = dev; if (!cpumask_empty(tick_get_broadcast_mask())) tick_broadcast_start_periodic(dev); -- cgit 1.2.3-korg From de28f25e8244c7353abed8de0c7792f5f883588c Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Fri, 2 Dec 2011 16:02:45 +0100 Subject: clockevents: Set noop handler in clockevents_exchange_device() If a device is shutdown, then there might be a pending interrupt, which will be processed after we reenable interrupts, which causes the original handler to be run. If the old handler is the (broadcast) periodic handler the shutdown state might hang the kernel completely. Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org --- kernel/time/clockevents.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 1ecd6ba36d6c6d..c4eb71c8b2ea32 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -387,6 +387,7 @@ void clockevents_exchange_device(struct clock_event_device *old, * released list and do a notify add later. */ if (old) { + old->event_handler = clockevents_handle_noop; clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED); list_del(&old->list); list_add(&old->list, &clockevents_released); -- cgit 1.2.3-korg