[PATCH v2 7/9] rtc; pcf2123: fix possible alarm race condition

From: Alexandre Belloni
Date: Wed Aug 14 2019 - 11:10:29 EST


Clear the flag after disabling the alarm to ensure the alarm doesn't fire
between clearing the flag and disabling the alarm.

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
---
drivers/rtc/rtc-pcf2123.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/rtc/rtc-pcf2123.c b/drivers/rtc/rtc-pcf2123.c
index 175aa8779623..26f43b619b48 100644
--- a/drivers/rtc/rtc-pcf2123.c
+++ b/drivers/rtc/rtc-pcf2123.c
@@ -272,13 +272,13 @@ static int pcf2123_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)

dev_dbg(dev, "%s: alm is %ptR\n", __func__, &alm->time);

- /* Ensure alarm flag is clear */
- ret = regmap_update_bits(pcf2123->map, PCF2123_REG_CTRL2, CTRL2_AF, 0);
+ /* Disable alarm interrupt */
+ ret = regmap_update_bits(pcf2123->map, PCF2123_REG_CTRL2, CTRL2_AIE, 0);
if (ret)
return ret;

- /* Disable alarm interrupt */
- ret = regmap_update_bits(pcf2123->map, PCF2123_REG_CTRL2, CTRL2_AIE, 0);
+ /* Ensure alarm flag is clear */
+ ret = regmap_update_bits(pcf2123->map, PCF2123_REG_CTRL2, CTRL2_AF, 0);
if (ret)
return ret;

--
2.21.0