arm64: dts: imx8mq-nitrogen: add lt8912 MIPI-DSI to HDMI

Add support of the lt8912b in the DTB.
This adds the support of the DB_DSIHD daugther board from
Boundary Devices.
Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq-nitrogen.dts

@@ -34,6 +34,19 @@ power {
 		};
 	};
 
+	hdmi-connector {
+		compatible = "hdmi-connector";
+		ddc-i2c-bus = <&ddc_i2c_bus>;
+		label = "hdmi";
+		type = "a";
+
+		port {
+			hdmi_connector_in: endpoint {
+				remote-endpoint = <&lt8912_out>;
+			};
+		};
+	};
+
 	reg_usb_otg_vbus: regulator-usb-otg-vbus {
 		compatible = "regulator-fixed";
 		pinctrl-names = "default";
@@ -81,6 +94,9 @@ reg_vref_5v: regulator-vref-5v {
 	};
 };
 
+&dphy {
+	status = "okay";
+};
 
 &fec1 {
 	pinctrl-names = "default";
@@ -194,6 +210,98 @@ rtc@68 {
 	};
 };
 
+&i2c4 {
+	clock-frequency = <100000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_i2c4>;
+	status = "okay";
+
+	pca9546: i2cmux@70 {
+		compatible = "nxp,pca9546";
+		reg = <0x70>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		i2c4@0 {
+			reg = <0>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			clock-frequency = <100000>;
+
+			hdmi-bridge@48 {
+				compatible = "lontium,lt8912b";
+				reg = <0x48> ;
+				reset-gpios = <&max7323 0 GPIO_ACTIVE_LOW>;
+
+				ports {
+					#address-cells = <1>;
+					#size-cells = <0>;
+
+					port@0 {
+						reg = <0>;
+
+						hdmi_out_in: endpoint {
+							data-lanes = <1 2 3 4>;
+							remote-endpoint = <&mipi_dsi_out>;
+						};
+					};
+
+					port@1 {
+						reg = <1>;
+
+						lt8912_out: endpoint {
+							remote-endpoint = <&hdmi_connector_in>;
+						};
+					};
+				};
+			};
+		};
+
+		ddc_i2c_bus: i2c4@1 {
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			clock-frequency = <100000>;
+		};
+
+		i2c4@3 {
+			reg = <3>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			clock-frequency = <100000>;
+
+			max7323: gpio-expander@68 {
+				compatible = "maxim,max7323";
+				pinctrl-names = "default";
+				pinctrl-0 = <&pinctrl_max7323>;
+				gpio-controller;
+				reg = <0x68>;
+				#gpio-cells = <2>;
+			};
+		};
+	};
+};
+
+&lcdif {
+	status = "okay";
+};
+
+&mipi_dsi {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	status = "okay";
+
+	ports {
+		port@1 {
+			reg = <1>;
+
+			mipi_dsi_out: endpoint {
+				remote-endpoint = <&hdmi_out_in>;
+			};
+		};
+	};
+};
+
 &uart1 { /* console */
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_uart1>;
@@ -364,6 +472,19 @@ MX8MQ_IOMUXC_GPIO1_IO06_GPIO1_IO6		0x49
 		>;
 	};
 
+	pinctrl_i2c4: i2c4grp {
+		fsl,pins = <
+			MX8MQ_IOMUXC_I2C4_SCL_I2C4_SCL			0x4000007f
+			MX8MQ_IOMUXC_I2C4_SDA_I2C4_SDA			0x4000007f
+		>;
+	};
+
+	pinctrl_max7323: max7323grp {
+		fsl,pins = <
+			MX8MQ_IOMUXC_NAND_RE_B_GPIO3_IO15 0x19
+		>;
+	};
+
 	pinctrl_reg_arm_dram: reg-arm-dramgrp {
 		fsl,pins = <
 			MX8MQ_IOMUXC_SAI5_RXD3_GPIO3_IO24	0x16