diff --git a/arch/arm/boot/dts/sh73a0-kzm9g.dts b/arch/arm/boot/dts/sh73a0-kzm9g.dts
index c2d8a080e392..9881adf1734e 100644
--- a/arch/arm/boot/dts/sh73a0-kzm9g.dts
+++ b/arch/arm/boot/dts/sh73a0-kzm9g.dts
@@ -378,6 +378,7 @@
 	pinctrl-0 = <&scifa4_pins>;
 	pinctrl-names = "default";
 
+	uart-has-rtscts;
 	status = "okay";
 };