[PATCH] rtc-sa1100 rtc_wklarm.enabled bugfixes

Some rtc-sa1100 bugfixes:

 - The read_alarm() method reports the rtc_wkalrm.enabled field properly.
   This patch is already in the handhelds.org tree.

 - And the set_alarm() method now handles that flag correctly, rather than
   making mismatched {en,dis}able_irq_wake() calls, which trigger runtime
   warning messages.  (Those calls are best made in suspend/resume methods.)

Note that while this SA1100/PXA RTC is fully capable of waking those ARM
processors from sleep states, that mechanism isn't properly supported on
either processor family, or in this driver.  Some boards have board-specific
PM glue providing partial workarounds for the weak generic PM support.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-sa1100.c

@@ -263,8 +263,12 @@ static int sa1100_rtc_set_time(struct device *dev, struct rtc_time *tm)
 
 static int sa1100_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 {
+	u32	rtsr;
+
 	memcpy(&alrm->time, &rtc_alarm, sizeof(struct rtc_time));
-	alrm->pending = RTSR & RTSR_AL ? 1 : 0;
+	rtsr = RTSR;
+	alrm->enabled = (rtsr & RTSR_ALE) ? 1 : 0;
+	alrm->pending = (rtsr & RTSR_AL) ? 1 : 0;
 	return 0;
 }
 
@@ -275,12 +279,10 @@ static int sa1100_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
 	spin_lock_irq(&sa1100_rtc_lock);
 	ret = rtc_update_alarm(&alrm->time);
 	if (ret == 0) {
-		memcpy(&rtc_alarm, &alrm->time, sizeof(struct rtc_time));
-
 		if (alrm->enabled)
-			enable_irq_wake(IRQ_RTCAlrm);
+			RTSR |= RTSR_ALE;
 		else
-			disable_irq_wake(IRQ_RTCAlrm);
+			RTSR &= ~RTSR_ALE;
 	}
 	spin_unlock_irq(&sa1100_rtc_lock);