diff --git a/drivers/tty/serial/mfd.c b/drivers/tty/serial/mfd.c
index c4b50af..79fe59b 100644
--- a/drivers/tty/serial/mfd.c
+++ b/drivers/tty/serial/mfd.c
@@ -36,6 +36,7 @@
 #include <linux/serial_mfd.h>
 #include <linux/dma-mapping.h>
 #include <linux/pci.h>
+#include <linux/nmi.h>
 #include <linux/io.h>
 #include <linux/debugfs.h>
 #include <linux/pm_runtime.h>
@@ -1113,6 +1114,8 @@
 	unsigned int ier;
 	int locked = 1;
 
+	touch_nmi_watchdog();
+
 	local_irq_save(flags);
 	if (up->port.sysrq)
 		locked = 0;