watchdog: mei_wdt: request stop on reboot to prevent false positive event

commit 9eff1140a82db8c5520f76e51c21827b4af670b3 upstream.

Systemd on reboot enables shutdown watchdog that leaves the watchdog
device open to ensure that even if power down process get stuck the
platform reboots nonetheless.
The iamt_wdt is an alarm-only watchdog and can't reboot system, but the
FW will generate an alarm event reboot was completed in time, as the
watchdog is not automatically disabled during power cycle.
So we should request stop watchdog on reboot to eliminate wrong alarm
from the FW.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/watchdog/mei_wdt.c b/drivers/watchdog/mei_wdt.c
index 630bd189f16788fac980690b745bede9a02e85ff..2a9d5cdedea2cf287cc98a55d77a3d6fc48d8ed9 100644 (file)
--- a/drivers/watchdog/mei_wdt.c
+++ b/drivers/watchdog/mei_wdt.c
@@ -389,6 +389,8 @@ static int mei_wdt_register(struct mei_wdt *wdt)
        wdt->wdd.max_timeout = MEI_WDT_MAX_TIMEOUT;
 
        watchdog_set_drvdata(&wdt->wdd, wdt);
+       watchdog_stop_on_reboot(&wdt->wdd);
+
        ret = watchdog_register_device(&wdt->wdd);
        if (ret) {
                dev_err(dev, "unable to register watchdog device = %d.\n", ret);