diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index 26173a270e944..5b395a4ddfdfe 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -392,7 +392,7 @@ static int iTCO_wdt_stop(void)
 
 	/* Bit 13: TCO_EN -> 1 = Enables the TCO logic to generate SMI# */
 	val32 = inl(SMI_EN);
-	val32 &= 0x00002000;
+	val32 |= 0x00002000;
 	outl(val32, SMI_EN);
 
 	/* Set the NO_REBOOT bit to prevent later reboots, just for sure */