On 7/26/20 8:46 PM, 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.packham@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> ---
> Changes in v3:
> - Check for watchdog flag in ds1307_wdt_register()
> Changes in v2:
> - Set bootstatus to WDIOF_CARDRESET and let userspace decide what to do with
> the information.
>
> drivers/rtc/rtc-ds1307.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
> index 49702942bb08..54c85cdd019d 100644
> --- a/drivers/rtc/rtc-ds1307.c
> +++ b/drivers/rtc/rtc-ds1307.c
> @@ -1668,6 +1668,8 @@ static const struct watchdog_ops ds1388_wdt_ops = {
> static void ds1307_wdt_register(struct ds1307 *ds1307)
> {
> struct watchdog_device *wdt;
> + int err;
> + int val;
>
> if (ds1307->type != ds_1388)
> return;
> @@ -1676,6 +1678,10 @@ static void ds1307_wdt_register(struct ds1307 *ds1307)
> if (!wdt)
> return;
>
> + err = regmap_read(ds1307->regmap, DS1388_REG_FLAG, &val);
> + if (!err && val & DS1388_BIT_WF)
> + wdt->bootstatus = WDIOF_CARDRESET;
> +
> wdt->info = &ds1388_wdt_info;
> wdt->ops = &ds1388_wdt_ops;
> wdt->timeout = 99;
>
