As suggested by Uwe, instead of clearing oscillator failure bit unconditionally at driver load, this patch adds proper handling of the flag. The driver now returns -ENODATA when reading time from the device and oscillator failure bit is set. The flag is now cleared only when the a new time value is pushed to the device.
Reported-by: Uwe Kleine-König <[email protected]> Signed-off-by: Arnaud Ebalard <[email protected]> --- drivers/rtc/rtc-isl12057.c | 47 ++++++++++++++++++++++++++++++++-------------- 1 file changed, 33 insertions(+), 14 deletions(-) diff --git a/drivers/rtc/rtc-isl12057.c b/drivers/rtc/rtc-isl12057.c index b538fabfcfd3..fe562820a54a 100644 --- a/drivers/rtc/rtc-isl12057.c +++ b/drivers/rtc/rtc-isl12057.c @@ -164,17 +164,32 @@ static int isl12057_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct isl12057_rtc_data *data = dev_get_drvdata(dev); u8 regs[ISL12057_RTC_SEC_LEN]; + unsigned int sr; int ret; mutex_lock(&data->lock); + ret = regmap_read(data->regmap, ISL12057_REG_SR, &sr); + if (ret) { + dev_err(dev, "%s: unable to read oscillator status flag\n", + __func__); + goto out; + } else { + if (sr & ISL12057_REG_SR_OSF) { + ret = -ENODATA; + goto out; + } + } + ret = regmap_bulk_read(data->regmap, ISL12057_REG_RTC_SC, regs, ISL12057_RTC_SEC_LEN); + if (ret) + dev_err(dev, "%s: unable to read RTC time\n", __func__); + +out: mutex_unlock(&data->lock); - if (ret) { - dev_err(dev, "%s: RTC read failed\n", __func__); + if (ret) return ret; - } isl12057_rtc_regs_to_tm(tm, regs); @@ -194,10 +209,22 @@ static int isl12057_rtc_set_time(struct device *dev, struct rtc_time *tm) mutex_lock(&data->lock); ret = regmap_bulk_write(data->regmap, ISL12057_REG_RTC_SC, regs, ISL12057_RTC_SEC_LEN); - mutex_unlock(&data->lock); + if (ret) { + dev_err(dev, "%s: writing RTC time failed\n", __func__); + goto out; + } - if (ret) - dev_err(dev, "%s: RTC write failed\n", __func__); + /* + * Now that RTC time has been updated, let's clear oscillator + * failure flag, if needed. + */ + ret = regmap_update_bits(data->regmap, ISL12057_REG_SR, + ISL12057_REG_SR_OSF, 0); + if (ret < 0) + dev_err(dev, "Unable to clear oscillator failure bit\n"); + +out: + mutex_unlock(&data->lock); return ret; } @@ -219,14 +246,6 @@ static int isl12057_check_rtc_status(struct device *dev, struct regmap *regmap) return ret; } - /* Clear oscillator failure bit if needed */ - ret = regmap_update_bits(regmap, ISL12057_REG_SR, - ISL12057_REG_SR_OSF, 0); - if (ret < 0) { - dev_err(dev, "Unable to clear oscillator failure bit\n"); - return ret; - } - /* Clear alarm bit if needed */ ret = regmap_update_bits(regmap, ISL12057_REG_SR, ISL12057_REG_SR_A1F, 0); -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
