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path: root/drivers/rtc/rtc-isl12057.c
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Diffstat (limited to 'drivers/rtc/rtc-isl12057.c')
-rw-r--r--drivers/rtc/rtc-isl12057.c83
1 files changed, 60 insertions, 23 deletions
diff --git a/drivers/rtc/rtc-isl12057.c b/drivers/rtc/rtc-isl12057.c
index 455b601d731..6e1fcfb5d7e 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;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-13 11:00:59 +0000