diff --git a/arch/mips/boot/dts/ralink/gardena_smart_gateway_mt7688.dts b/arch/mips/boot/dts/ralink/gardena_smart_gateway_mt7688.dts
index 2d979eb744dc..6069b33cf09f 100644
--- a/arch/mips/boot/dts/ralink/gardena_smart_gateway_mt7688.dts
+++ b/arch/mips/boot/dts/ralink/gardena_smart_gateway_mt7688.dts
@@ -177,6 +177,9 @@ &uart1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinmux_i2s_gpio>;		/* GPIO0..3 */
 
+	fifo-size = <8>;
+	tx-threshold = <8>;
+
 	rts-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
 	cts-gpios = <&gpio 2 GPIO_ACTIVE_LOW>;
 };