diff options
Diffstat (limited to 'drivers/rtc/rtc-cmos.c')
| -rw-r--r-- | drivers/rtc/rtc-cmos.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 51e80bc70d42..a701dae653c4 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -805,6 +805,14 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq) spin_lock_irq(&rtc_lock); + /* Ensure that the RTC is accessible. Bit 6 must be 0! */ + if ((CMOS_READ(RTC_VALID) & 0x40) != 0) { + spin_unlock_irq(&rtc_lock); + dev_warn(dev, "not accessible\n"); + retval = -ENXIO; + goto cleanup1; + } + if (!(flags & CMOS_RTC_FLAGS_NOFREQ)) { /* force periodic irq to CMOS reset default of 1024Hz; * |