[ 069/104] drivers/rtc/rtc-cmos.c: dont disable hpet emulation on suspend

From: Greg Kroah-Hartman
Date: Mon May 06 2013 - 19:24:59 EST


3.8-stable review patch. If anyone has any objections, please let me know.

------------------

From: Derek Basehore <dbasehore@xxxxxxxxxxxx>

commit e005715efaf674660ae59af83b13822567e3a758 upstream.

There's a bug where rtc alarms are ignored after the rtc cmos suspends
but before the system finishes suspend. Since hpet emulation is
disabled and it still handles the interrupts, a wake event is never
registered which is done from the rtc layer.

This patch reverts commit d1b2efa83fbf ("rtc: disable hpet emulation on
suspend") which disabled hpet emulation. To fix the problem mentioned
in that commit, hpet_rtc_timer_init() is called directly on resume.

Signed-off-by: Derek Basehore <dbasehore@xxxxxxxxxxxx>
Cc: Maxim Levitsky <maximlevitsky@xxxxxxxxx>
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/rtc/rtc-cmos.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -805,9 +805,8 @@ static int cmos_suspend(struct device *d
mask = RTC_IRQMASK;
tmp &= ~mask;
CMOS_WRITE(tmp, RTC_CONTROL);
+ hpet_mask_rtc_irq_bit(mask);

- /* shut down hpet emulation - we don't need it for alarm */
- hpet_mask_rtc_irq_bit(RTC_PIE|RTC_AIE|RTC_UIE);
cmos_checkintr(cmos, tmp);
}
spin_unlock_irq(&rtc_lock);
@@ -872,6 +871,7 @@ static int cmos_resume(struct device *de
rtc_update_irq(cmos->rtc, 1, mask);
tmp &= ~RTC_AIE;
hpet_mask_rtc_irq_bit(RTC_AIE);
+ hpet_rtc_timer_init();
} while (mask & RTC_AIE);
spin_unlock_irq(&rtc_lock);
}


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