drivers/rtc/rtc-omap.c: enable RTC_IRQWAKEEN bits when Alarm is set

When RTC CLKTRCTRL bit is configured in HW_AUTO, module goes to sleep in
IDLE state.

The Alarm SWakeup event can be used to wakeup the RTC when it is in IDLE
state.  In order to do so, the alarm needs to be set and enabled before
RTC enters the IDLE state.  Also the wakeup generation for alarm/timer
event needs to be set (bits [1:0] in RTC_IRQWAKEEN register).

Currently RTC_IRQWAKEEN bits are set only in suspend/resume paths.  With
this ALARM interrupts are not generated when it enters IDLE state.  So
programming the RTC_IRQWAKEEN bits when ever ALARM is set.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
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-omap.c

@@ -171,17 +171,28 @@ static irqreturn_t rtc_irq(int irq, void *rtc)
 
 static int omap_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
 {
-	u8 reg;
+	u8 reg, irqwake_reg = 0;
+	struct platform_device *pdev = to_platform_device(dev);
+	const struct platform_device_id *id_entry =
+					platform_get_device_id(pdev);
 
 	local_irq_disable();
 	rtc_wait_not_busy();
 	reg = rtc_read(OMAP_RTC_INTERRUPTS_REG);
-	if (enabled)
+	if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
+		irqwake_reg = rtc_read(OMAP_RTC_IRQWAKEEN);
+
+	if (enabled) {
 		reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
-	else
+		irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+	} else {
 		reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
+		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+	}
 	rtc_wait_not_busy();
 	rtc_write(reg, OMAP_RTC_INTERRUPTS_REG);
+	if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
+		rtc_write(irqwake_reg, OMAP_RTC_IRQWAKEEN);
 	local_irq_enable();
 
 	return 0;
@@ -281,7 +292,10 @@ static int omap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 
 static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 {
-	u8 reg;
+	u8 reg, irqwake_reg = 0;
+	struct platform_device *pdev = to_platform_device(dev);
+	const struct platform_device_id *id_entry =
+					platform_get_device_id(pdev);
 
 	if (tm2bcd(&alm->time) < 0)
 		return -EINVAL;
@@ -297,11 +311,19 @@ static int omap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	rtc_write(alm->time.tm_sec, OMAP_RTC_ALARM_SECONDS_REG);
 
 	reg = rtc_read(OMAP_RTC_INTERRUPTS_REG);
-	if (alm->enabled)
+	if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
+		irqwake_reg = rtc_read(OMAP_RTC_IRQWAKEEN);
+
+	if (alm->enabled) {
 		reg |= OMAP_RTC_INTERRUPTS_IT_ALARM;
-	else
+		irqwake_reg |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+	} else {
 		reg &= ~OMAP_RTC_INTERRUPTS_IT_ALARM;
+		irqwake_reg &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
+	}
 	rtc_write(reg, OMAP_RTC_INTERRUPTS_REG);
+	if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN)
+		rtc_write(irqwake_reg, OMAP_RTC_IRQWAKEEN);
 
 	local_irq_enable();
 
@@ -503,28 +525,16 @@ static u8 irqstat;
 
 static int omap_rtc_suspend(struct device *dev)
 {
-	u8 irqwake_stat;
-	struct platform_device *pdev = to_platform_device(dev);
-	const struct platform_device_id *id_entry =
-					platform_get_device_id(pdev);
-
 	irqstat = rtc_read(OMAP_RTC_INTERRUPTS_REG);
 
 	/* FIXME the RTC alarm is not currently acting as a wakeup event
 	 * source on some platforms, and in fact this enable() call is just
 	 * saving a flag that's never used...
 	 */
-	if (device_may_wakeup(dev)) {
+	if (device_may_wakeup(dev))
 		enable_irq_wake(omap_rtc_alarm);
-
-		if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN) {
-			irqwake_stat = rtc_read(OMAP_RTC_IRQWAKEEN);
-			irqwake_stat |= OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
-			rtc_write(irqwake_stat, OMAP_RTC_IRQWAKEEN);
-		}
-	} else {
+	else
 		rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
-	}
 
 	/* Disable the clock/module */
 	pm_runtime_put_sync(dev);
@@ -534,25 +544,14 @@ static int omap_rtc_suspend(struct device *dev)
 
 static int omap_rtc_resume(struct device *dev)
 {
-	u8 irqwake_stat;
-	struct platform_device *pdev = to_platform_device(dev);
-	const struct platform_device_id *id_entry =
-				platform_get_device_id(pdev);
-
 	/* Enable the clock/module so that we can access the registers */
 	pm_runtime_get_sync(dev);
 
-	if (device_may_wakeup(dev)) {
+	if (device_may_wakeup(dev))
 		disable_irq_wake(omap_rtc_alarm);
-
-		if (id_entry->driver_data & OMAP_RTC_HAS_IRQWAKEEN) {
-			irqwake_stat = rtc_read(OMAP_RTC_IRQWAKEEN);
-			irqwake_stat &= ~OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN;
-			rtc_write(irqwake_stat, OMAP_RTC_IRQWAKEEN);
-		}
-	} else {
+	else
 		rtc_write(irqstat, OMAP_RTC_INTERRUPTS_REG);
-	}
+
 	return 0;
 }
 #endif