From 9bf1306257589b3a5ad46175538af9922d94e26f Mon Sep 17 00:00:00 2001 From: Chris Packham Date: Mon, 27 Jul 2020 15:46:14 +1200 Subject: [PATCH] rtc: ds1307: provide an indication that the watchdog has fired 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 Signed-off-by: Alexandre Belloni Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20200727034615.19755-1-chris.packham@alliedtelesis.co.nz --- 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 4970294..54c85cd 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; -- 2.7.4