Power-on reset after the insertion of a battery does not always complete successfully, leading to corrupted register content. The EXT_TEST bit will stop the clock from running, but currently the driver will never recover. Safely handle the erroneous state by clearing EXT_TEST as part of the usual set_time method. Signed-off-by: Phil Elwell <phil@xxxxxxxxxxxxxxx> --- drivers/rtc/rtc-pcf85063.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c index 14da4ab30104..ea75b71a1f16 100644 --- a/drivers/rtc/rtc-pcf85063.c +++ b/drivers/rtc/rtc-pcf85063.c @@ -34,6 +34,7 @@ #define PCF85063_REG_CTRL1 0x00 /* status */ #define PCF85063_REG_CTRL1_CAP_SEL BIT(0) #define PCF85063_REG_CTRL1_STOP BIT(5) +#define PCF85063_REG_CTRL1_EXT_TEST BIT(7) #define PCF85063_REG_CTRL2 0x01 #define PCF85063_CTRL2_AF BIT(6) @@ -117,6 +118,7 @@ static int pcf85063_rtc_set_time(struct device *dev, struct rtc_time *tm) * reset state until all time/date registers are written */ rc = regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL1, + PCF85063_REG_CTRL1_EXT_TEST | PCF85063_REG_CTRL1_STOP, PCF85063_REG_CTRL1_STOP); if (rc) -- 2.25.1
