diff -Nru linux-3.14.63/arch/arm/boot/dts/am335x-lctr-b2xx.dts linux-3.14.63.mc/arch/arm/boot/dts/am335x-lctr-b2xx.dts
--- linux-3.14.63/arch/arm/boot/dts/am335x-lctr-b2xx.dts	2017-01-17 14:12:07.019022866 +0000
+++ linux-3.14.63.mc/arch/arm/boot/dts/am335x-lctr-b2xx.dts	2017-01-17 14:26:45.657383756 +0000
@@ -60,6 +60,16 @@
 			0x154 (PIN_OUTPUT_PULLDOWN | MUX_MODE1)
 		>;
 	};
+
+	/* UART4. */
+	uart4_pins: pinmux_uart4_pins {
+		pinctrl-single,pins = <
+			/* uart4_rxd */
+			0x70 (PIN_INPUT_PULLUP | MUX_MODE6)
+			/* uart4_txd */
+			0x74 (PIN_OUTPUT_PULLDOWN | MUX_MODE6)
+		>;
+	};
 };
 
 /* Enable UART1. */
@@ -75,3 +85,10 @@
 	pinctrl-0 = <&uart2_pins>;
 	status = "okay";
 };
+
+/* Enable UART4. */
+&uart4 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart4_pins>;
+	status = "okay";
+};