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| author | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2019-12-14 23:02:50 +0100 |
|---|---|---|
| committer | Alexandre Belloni <alexandre.belloni@bootlin.com> | 2019-12-18 10:37:30 +0100 |
| commit | 935272aade5ac17f6e6139968799421233c92c33 (patch) | |
| tree | 200a2ccc9ebfc88e98dfa5c4f01b04db3e755dad /drivers/rtc/rtc-pcf8563.c | |
| parent | 75d26f5c2388f0fbedceeec98a3dc95cb26ec1c8 (diff) | |
| download | linux-935272aade5ac17f6e6139968799421233c92c33.tar.gz | |
rtc: pcf8563: stop caching voltage_low
voltage_low is only updated when reading the time, this means that using
RTC_VL_READ will miss the VL flag if the time has not been read before
using the ioctl. Always read the status from the hardware.
Link: https://lore.kernel.org/r/20191214220259.621996-9-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Diffstat (limited to 'drivers/rtc/rtc-pcf8563.c')
| -rw-r--r-- | drivers/rtc/rtc-pcf8563.c | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/drivers/rtc/rtc-pcf8563.c b/drivers/rtc/rtc-pcf8563.c index 026192fc0c2aa..7fc43950cf6c9 100644 --- a/drivers/rtc/rtc-pcf8563.c +++ b/drivers/rtc/rtc-pcf8563.c @@ -76,7 +76,6 @@ struct pcf8563 { * 1970...2069. */ int c_polarity; /* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */ - int voltage_low; /* incicates if a low_voltage was detected */ struct i2c_client *client; #ifdef CONFIG_COMMON_CLK @@ -208,7 +207,6 @@ static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm) return err; if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) { - pcf8563->voltage_low = 1; dev_err(&client->dev, "low voltage detected, date/time is not reliable.\n"); return -EINVAL; @@ -278,15 +276,19 @@ static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm) static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) { - struct pcf8563 *pcf8563 = i2c_get_clientdata(to_i2c_client(dev)); + struct i2c_client *client = to_i2c_client(dev); + int vl, ret; switch (cmd) { case RTC_VL_READ: - if (pcf8563->voltage_low) - dev_info(dev, "low voltage detected, date/time is not reliable.\n"); - if (copy_to_user((void __user *)arg, &pcf8563->voltage_low, - sizeof(int))) + ret = i2c_smbus_read_byte_data(client, PCF8563_REG_SC); + if (ret < 0) + return ret; + + vl = ret & PCF8563_SC_LV ? 1 : 0; + + if (copy_to_user((void __user *)arg, &vl, sizeof(int))) return -EFAULT; return 0; default: |