diff options
Diffstat (limited to 'drivers/rtc/rtc-pcf2127.c')
| -rw-r--r-- | drivers/rtc/rtc-pcf2127.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/drivers/rtc/rtc-pcf2127.c b/drivers/rtc/rtc-pcf2127.c index 350c5c7cb678..baf45c9ca65e 100644 --- a/drivers/rtc/rtc-pcf2127.c +++ b/drivers/rtc/rtc-pcf2127.c @@ -33,11 +33,14 @@ #define PCF2127_REG_MO (0x08) #define PCF2127_REG_YR (0x09) +#define PCF2127_OSF BIT(7) /* Oscillator Fail flag */ + static struct i2c_driver pcf2127_driver; struct pcf2127 { struct rtc_device *rtc; int voltage_low; /* indicates if a low_voltage was detected */ + int oscillator_failed; /* OSF was detected and date is unreliable */ }; /* @@ -59,7 +62,18 @@ static int pcf2127_get_datetime(struct i2c_client *client, struct rtc_time *tm) if (buf[PCF2127_REG_CTRL3] & 0x04) { pcf2127->voltage_low = 1; dev_info(&client->dev, - "low voltage detected, date/time is not reliable.\n"); + "low voltage detected, check/replace RTC battery.\n"); + } + + if (buf[PCF2127_REG_SC] & PCF2127_OSF) { + /* + * no need clear the flag here, + * it will be cleared once the new date is saved + */ + pcf2127->oscillator_failed = 1; + dev_warn(&client->dev, + "oscillator stop detected, date/time is not reliable\n"); + return -EINVAL; } dev_dbg(&client->dev, @@ -93,6 +107,7 @@ static int pcf2127_get_datetime(struct i2c_client *client, struct rtc_time *tm) static int pcf2127_set_datetime(struct i2c_client *client, struct rtc_time *tm) { + struct pcf2127 *pcf2127 = i2c_get_clientdata(client); unsigned char buf[8]; int i = 0, err; @@ -106,7 +121,7 @@ static int pcf2127_set_datetime(struct i2c_client *client, struct rtc_time *tm) buf[i++] = PCF2127_REG_SC; /* hours, minutes and seconds */ - buf[i++] = bin2bcd(tm->tm_sec); + buf[i++] = bin2bcd(tm->tm_sec); /* this will also clear OSF flag */ buf[i++] = bin2bcd(tm->tm_min); buf[i++] = bin2bcd(tm->tm_hour); buf[i++] = bin2bcd(tm->tm_mday); @@ -126,6 +141,9 @@ static int pcf2127_set_datetime(struct i2c_client *client, struct rtc_time *tm) return -EIO; } + /* clear OSF flag in client data */ + pcf2127->oscillator_failed = 0; + return 0; } @@ -138,7 +156,9 @@ static int pcf2127_rtc_ioctl(struct device *dev, switch (cmd) { case RTC_VL_READ: if (pcf2127->voltage_low) - dev_info(dev, "low voltage detected, date/time is not reliable.\n"); + dev_info(dev, "low voltage detected, check/replace battery\n"); + if (pcf2127->oscillator_failed) + dev_info(dev, "oscillator stop detected, date/time is not reliable\n"); if (copy_to_user((void __user *)arg, &pcf2127->voltage_low, sizeof(int))) |