toradex-smarc-imx8mp: dsi-to-hdmi: Add overlay

Add overlay for the DSI to HDMI adapter, the same that is used with the
Verdin family.

Related-to: ELB-6063
Signed-off-by: João Paulo Gonçalves <joao.goncalves@toradex.com>

2 files changed, 106 insertions, 0 deletions

diff --git a/overlays/Makefile b/overlays/Makefile
index 9a6d0e2..56c176c 100644
--- a/overlays/Makefile
+++ b/overlays/Makefile
@@ -41,6 +41,7 @@ dtb-y += colibri-imx8x_panel-res-touch-7inch_overlay.dtbo
 dtb-y += colibri-imx8x_panel-cap-touch-10inch-lvds_overlay.dtbo
 dtb-y += colibri-imx8x_vga-640x480_overlay.dtbo
 dtb-y += colibri-imx8x_spidev_overlay.dtbo
+dtb-y += toradex-smarc-imx8mp_dsi-to-hdmi_overlay.dtbo
 dtb-y += verdin-imx8mm_20mhz_can1.dtbo
 dtb-y += verdin-imx8mm_disable_can1.dtbo
 dtb-y += verdin-imx8mm_dsi-to-hdmi_overlay.dtbo
diff --git a/overlays/toradex-smarc-imx8mp_dsi-to-hdmi_overlay.dts b/overlays/toradex-smarc-imx8mp_dsi-to-hdmi_overlay.dts
new file mode 100644
index 0000000..8d609f9
--- /dev/null
+++ b/overlays/toradex-smarc-imx8mp_dsi-to-hdmi_overlay.dts
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+/*
+ * Copyright (C) 2025 Toradex
+ *
+ * LT8912B MIPI DSI to HDMI accessory
+ *
+ * https://developer.toradex.com/hardware/accessories/add-ons/dsi-hdmi-adapter
+ * https://www.toradex.com/accessories/verdin-dsi-to-hdmi-adapter
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include "imx8mp-pinfunc.h"
+
+/ {
+	compatible = "toradex,toradex-smarc-imx8mp";
+};
+
+&{/} {
+	hdmi-connector {
+		compatible = "hdmi-connector";
+		pinctrl-names = "default";
+		pinctrl-0 = <&pinctrl_hdmi_hpd>;
+		/* I2C on DSI Connector Pins 52/54 */
+		ddc-i2c-bus = <&i2c_dsi_1>;
+		/* SMARC LCD1_BKLT_PWM as GPIO */
+		hpd-gpios = <&gpio5 5 GPIO_ACTIVE_HIGH>;
+		label = "hdmi";
+		type = "a";
+
+		port {
+			hdmi_connector_in: endpoint {
+				remote-endpoint = <&lt8912_out>;
+			};
+		};
+	};
+};
+
+/* I2C on DSI Connector Pins 4/6 */
+&i2c_dsi_0 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+
+	bridge@48 {
+		compatible = "lontium,lt8912b";
+		reg = <0x48>;
+		/* SMARC LCD1_BKLT_EN */
+		reset-gpios = <&som_gpio_expander 7 GPIO_ACTIVE_LOW>;
+
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
+				reg = <0>;
+
+				lt8912_1_in: endpoint {
+					data-lanes = <1 2 3 4>;
+					remote-endpoint = <&mipi_dsi_bridge1_out>;
+				};
+			};
+
+			port@1 {
+				reg = <1>;
+
+				lt8912_out: endpoint {
+					remote-endpoint = <&hdmi_connector_in>;
+				};
+			};
+		};
+	};
+};
+
+&lcdif1 {
+	status = "okay";
+};
+
+&mipi_dsi {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	status = "okay";
+
+	port@1 {
+		reg = <1>;
+
+		mipi_dsi_bridge1_out: endpoint {
+			attach-bridge;
+			remote-endpoint = <&lt8912_1_in>;
+		};
+	};
+};
+
+/* SMARC LCD1_BKLT_PWM - Used as GPIO */
+&pwm1 {
+	status = "disabled";
+};
+
+&iomuxc {
+	/* SMARC LCD1_BKLT_PWM as GPIO */
+	pinctrl_hdmi_hpd: hdmihpdgpiogrp {
+		fsl,pins = <MX8MP_IOMUXC_SPDIF_EXT_CLK__GPIO5_IO05	0x104>; /* SMARC S122 - LCD1_BKLT_PWM */
+	};
+};