diff options
Diffstat (limited to 'drivers/rtc/rtc-isl12057.c')
| -rw-r--r-- | drivers/rtc/rtc-isl12057.c | 83 |
1 files changed, 60 insertions, 23 deletions
diff --git a/drivers/rtc/rtc-isl12057.c b/drivers/rtc/rtc-isl12057.c index 455b601d731d..6e1fcfb5d7e6 100644 --- a/drivers/rtc/rtc-isl12057.c +++ b/drivers/rtc/rtc-isl12057.c @@ -41,6 +41,7 @@ #define ISL12057_REG_RTC_DW 0x03 /* Day of the Week */ #define ISL12057_REG_RTC_DT 0x04 /* Date */ #define ISL12057_REG_RTC_MO 0x05 /* Month */ +#define ISL12057_REG_RTC_MO_CEN BIT(7) /* Century bit */ #define ISL12057_REG_RTC_YR 0x06 /* Year */ #define ISL12057_RTC_SEC_LEN 7 @@ -88,7 +89,7 @@ static void isl12057_rtc_regs_to_tm(struct rtc_time *tm, u8 *regs) tm->tm_min = bcd2bin(regs[ISL12057_REG_RTC_MN]); if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_MIL) { /* AM/PM */ - tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x0f); + tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x1f); if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_PM) tm->tm_hour += 12; } else { /* 24 hour mode */ @@ -97,26 +98,37 @@ static void isl12057_rtc_regs_to_tm(struct rtc_time *tm, u8 *regs) tm->tm_mday = bcd2bin(regs[ISL12057_REG_RTC_DT]); tm->tm_wday = bcd2bin(regs[ISL12057_REG_RTC_DW]) - 1; /* starts at 1 */ - tm->tm_mon = bcd2bin(regs[ISL12057_REG_RTC_MO]) - 1; /* starts at 1 */ + tm->tm_mon = bcd2bin(regs[ISL12057_REG_RTC_MO] & 0x1f) - 1; /* ditto */ tm->tm_year = bcd2bin(regs[ISL12057_REG_RTC_YR]) + 100; + + /* Check if years register has overflown from 99 to 00 */ + if (regs[ISL12057_REG_RTC_MO] & ISL12057_REG_RTC_MO_CEN) + tm->tm_year += 100; } static int isl12057_rtc_tm_to_regs(u8 *regs, struct rtc_time *tm) { + u8 century_bit; + /* * The clock has an 8 bit wide bcd-coded register for the year. + * It also has a century bit encoded in MO flag which provides + * information about overflow of year register from 99 to 00. * tm_year is an offset from 1900 and we are interested in the - * 2000-2099 range, so any value less than 100 is invalid. + * 2000-2199 range, so any value less than 100 or larger than + * 299 is invalid. */ - if (tm->tm_year < 100) + if (tm->tm_year < 100 || tm->tm_year > 299) return -EINVAL; + century_bit = (tm->tm_year > 199) ? ISL12057_REG_RTC_MO_CEN : 0; + regs[ISL12057_REG_RTC_SC] = bin2bcd(tm->tm_sec); regs[ISL12057_REG_RTC_MN] = bin2bcd(tm->tm_min); regs[ISL12057_REG_RTC_HR] = bin2bcd(tm->tm_hour); /* 24-hour format */ regs[ISL12057_REG_RTC_DT] = bin2bcd(tm->tm_mday); - regs[ISL12057_REG_RTC_MO] = bin2bcd(tm->tm_mon + 1); - regs[ISL12057_REG_RTC_YR] = bin2bcd(tm->tm_year - 100); + regs[ISL12057_REG_RTC_MO] = bin2bcd(tm->tm_mon + 1) | century_bit; + regs[ISL12057_REG_RTC_YR] = bin2bcd(tm->tm_year % 100); regs[ISL12057_REG_RTC_DW] = bin2bcd(tm->tm_wday + 1); return 0; @@ -152,17 +164,33 @@ 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 (%d)\n", + __func__, ret); + 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 section (%d)\n", + __func__, ret); + +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); @@ -182,10 +210,24 @@ 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: unable to write RTC time section (%d)\n", + __func__, ret); + 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, "%s: unable to clear osc. failure bit (%d)\n", + __func__, ret); + +out: + mutex_unlock(&data->lock); return ret; } @@ -203,15 +245,8 @@ static int isl12057_check_rtc_status(struct device *dev, struct regmap *regmap) ret = regmap_update_bits(regmap, ISL12057_REG_INT, ISL12057_REG_INT_EOSC, 0); if (ret < 0) { - dev_err(dev, "Unable to enable oscillator\n"); - 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"); + dev_err(dev, "%s: unable to enable oscillator (%d)\n", + __func__, ret); return ret; } @@ -219,7 +254,8 @@ static int isl12057_check_rtc_status(struct device *dev, struct regmap *regmap) ret = regmap_update_bits(regmap, ISL12057_REG_SR, ISL12057_REG_SR_A1F, 0); if (ret < 0) { - dev_err(dev, "Unable to clear alarm bit\n"); + dev_err(dev, "%s: unable to clear alarm bit (%d)\n", + __func__, ret); return ret; } @@ -253,7 +289,8 @@ static int isl12057_probe(struct i2c_client *client, regmap = devm_regmap_init_i2c(client, &isl12057_rtc_regmap_config); if (IS_ERR(regmap)) { ret = PTR_ERR(regmap); - dev_err(dev, "regmap allocation failed: %d\n", ret); + dev_err(dev, "%s: regmap allocation failed (%d)\n", + __func__, ret); return ret; } |