drivers/rtc/rtc-r9701.c: reset registers if invalid values are detected

hwclock refuses to set date/time if RTC registers contain invalid
values.  Check the date/time register values at probe time and
initialize them to make hwclock happy.

Signed-off-by: Andreas Dumberger <andreas.dumberger@tqs.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Andreas Dumberger 2012-04-12 12:49:12 -07:00 committed by Linus Torvalds
parent 44e4360fa3
commit bb58da08f0

View file

@ -122,6 +122,7 @@ static const struct rtc_class_ops r9701_rtc_ops = {
static int __devinit r9701_probe(struct spi_device *spi)
{
struct rtc_device *rtc;
struct rtc_time dt;
unsigned char tmp;
int res;
@ -132,6 +133,27 @@ static int __devinit r9701_probe(struct spi_device *spi)
return -ENODEV;
}
/*
* The device seems to be present. Now check if the registers
* contain invalid values. If so, try to write a default date:
* 2000/1/1 00:00:00
*/
r9701_get_datetime(&spi->dev, &dt);
if (rtc_valid_tm(&dt)) {
dev_info(&spi->dev, "trying to repair invalid date/time\n");
dt.tm_sec = 0;
dt.tm_min = 0;
dt.tm_hour = 0;
dt.tm_mday = 1;
dt.tm_mon = 0;
dt.tm_year = 100;
if (r9701_set_datetime(&spi->dev, &dt)) {
dev_err(&spi->dev, "cannot repair RTC register\n");
return -ENODEV;
}
}
rtc = rtc_device_register("r9701",
&spi->dev, &r9701_rtc_ops, THIS_MODULE);
if (IS_ERR(rtc))