On Mon, Jul 27, 2020 at 11:13:06AM +1200, Chris Packham wrote: > There's not much feedback when the ds1388 watchdog fires. Generally it > yanks on the reset line and the board reboots. Capture the fact that the > watchdog has fired in the past so that userspace can retrieve it via > WDIOC_GETBOOTSTATUS. This should help distinguish a watchdog triggered > reset from a power interruption. > > Signed-off-by: Chris Packham <chris.pack...@alliedtelesis.co.nz> > --- > Changes in v2: > - Set bootstatus to WDIOF_CARDRESET and let userspace decide what to do with > the information. > > drivers/rtc/rtc-ds1307.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c > index 49702942bb08..209736db510d 100644 > --- a/drivers/rtc/rtc-ds1307.c > +++ b/drivers/rtc/rtc-ds1307.c > @@ -868,6 +868,14 @@ static int ds1388_wdt_start(struct watchdog_device > *wdt_dev) > struct ds1307 *ds1307 = watchdog_get_drvdata(wdt_dev); > u8 regs[2]; > int ret; > + int val; > + > + ret = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &val); > + if (ret) > + return ret; > + > + if (val & DS1388_BIT_WF) > + wdt_dev->bootstatus = WDIOF_CARDRESET;
This should be done during probe, ie in ds1307_wdt_register(). Guenter > > ret = regmap_update_bits(ds1307->regmap, DS1388_REG_FLAG, > DS1388_BIT_WF, 0); > -- > 2.27.0 >
