The datasheet of the PCF2127 states,it is recommended to process an OTP refresh once the power is up and the oscillator is operating stable. The OTP refresh takes less than 100 ms to complete.
Signed-off-by: Philipp Rosenberger <[email protected]> --- drivers/rtc/rtc-pcf2127.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c index 378b1ce812d6..ca56dba64e79 100644 --- a/drivers/rtc/rtc-pcf2127.c +++ b/drivers/rtc/rtc-pcf2127.c @@ -58,6 +58,9 @@ #define PCF2127_REG_ALARM_DM 0x0D #define PCF2127_REG_ALARM_DW 0x0E #define PCF2127_BIT_ALARM_AE BIT(7) +/* CLKOUT control register */ +#define PCF2127_REG_CLKOUT 0x0f +#define PCF2127_BIT_CLKOUT_OTPR BIT(5) /* Watchdog registers */ #define PCF2127_REG_WD_CTL 0x10 #define PCF2127_BIT_WD_CTL_TF0 BIT(0) @@ -630,6 +633,19 @@ static int pcf2127_probe(struct device *dev, struct regmap *regmap, dev_warn(dev, "Watchdog and alarm functions might not work properly\n"); } + /* + * Set the OTP refresh bit unconditionally. If an OTP refresh was + * already done the bit is already set and will not rerun the refresh + * operation. + */ + ret = regmap_set_bits(pcf2127->regmap, PCF2127_REG_CLKOUT, + PCF2127_BIT_CLKOUT_OTPR); + if (ret < 0) { + dev_err(dev, "%s: OTP refresh (clkout_ctrl) failed.\n", __func__); + return ret; + } + msleep(100); + /* * Watchdog timer enabled and reset pin /RST activated when timed out. * Select 1Hz clock source for watchdog timer. -- 2.29.2
