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(-) (limited to 'drivers') diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index 3195dbd3ec34..e3cf2f54221f 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 v1.2.3 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(-) (limited to 'drivers') diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c index 01a7df5317c1..b82a1554cdc1 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 v1.2.3