diff --git a/drivers/tty/serial/dz.c b/drivers/tty/serial/dz.c
index 2e21acf39720..3eaf4e85bfdd 100644
--- a/drivers/tty/serial/dz.c
+++ b/drivers/tty/serial/dz.c
@@ -592,9 +592,12 @@ static void dz_set_termios(struct uart_port *uport, struct ktermios *termios,
 
 	baud = uart_get_baud_rate(uport, termios, old_termios, 50, 9600);
 	bflag = dz_encode_baud_rate(baud);
-	if (bflag < 0)	{			/* Try to keep unchanged.  */
-		baud = uart_get_baud_rate(uport, old_termios, NULL, 50, 9600);
-		bflag = dz_encode_baud_rate(baud);
+	if (bflag < 0)	{
+		if (old_termios) {
+			/* Keep unchanged. */
+			baud = tty_termios_baud_rate(old_termios);
+			bflag = dz_encode_baud_rate(baud);
+		}
 		if (bflag < 0)	{		/* Resort to 9600.  */
 			baud = 9600;
 			bflag = DZ_B9600;