rtc: ds3232: fix read on /dev/rtc after RTC_AIE_ON
The rtctest (tools/testing/selftests/timers/rtctest.c) found that
reading ds3232 rtc device immediately return the value 0x20 (RTC_AF)
without waiting alarm interrupt.
This is because alarm_irq_enable() of ds3232 driver changes RTC_AF
flag in rtc->irq_data. So calling ioctl with RTC_AIE_ON generates
invalid value in rtc device.
The lower-level driver should not touch rtc->irq_data directly.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c
index ca43bfc..6bf7848 100644
--- a/drivers/rtc/rtc-ds3232.c
+++ b/drivers/rtc/rtc-ds3232.c
@@ -272,7 +272,7 @@
return ret;
}
-static void ds3232_update_alarm(struct device *dev)
+static void ds3232_update_alarm(struct device *dev, unsigned int enabled)
{
struct ds3232 *ds3232 = dev_get_drvdata(dev);
int control;
@@ -302,7 +302,7 @@
if (ret)
goto unlock;
- if (ds3232->rtc->irq_data & (RTC_AF | RTC_UF))
+ if (enabled || (ds3232->rtc->irq_data & RTC_UF))
/* enable alarm1 interrupt */
control |= DS3232_REG_CR_A1IE;
else
@@ -321,12 +321,8 @@
if (ds3232->irq <= 0)
return -EINVAL;
- if (enabled)
- ds3232->rtc->irq_data |= RTC_AF;
- else
- ds3232->rtc->irq_data &= ~RTC_AF;
+ ds3232_update_alarm(dev, enabled);
- ds3232_update_alarm(dev);
return 0;
}