diff options
Diffstat (limited to 'drivers/rtc/rtc-ds1307.c')
-rw-r--r-- | drivers/rtc/rtc-ds1307.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index 506b7d1c2397..bdb7b201a160 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -65,6 +65,7 @@ enum ds_type { # define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */ # define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */ #define DS1307_REG_WDAY 0x03 /* 01-07 */ +# define MCP794XX_BIT_OSCRUN BIT(5) # define MCP794XX_BIT_VBATEN 0x08 #define DS1307_REG_MDAY 0x04 /* 01-31 */ #define DS1307_REG_MONTH 0x05 /* 01-12 */ @@ -242,6 +243,10 @@ static int ds1307_get_time(struct device *dev, struct rtc_time *t) regs[DS1307_REG_MIN] & M41T0_BIT_OF) { dev_warn_once(dev, "oscillator failed, set time!\n"); return -EINVAL; + } else if (ds1307->type == mcp794xx && + !(regs[DS1307_REG_WDAY] & MCP794XX_BIT_OSCRUN)) { + dev_warn_once(dev, "oscillator failed, set time!\n"); + return -EINVAL; } tmp = regs[DS1307_REG_SECS]; |