Latest revision as of 17:37, 20 March 2024

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DART-MX8M-MINI Display

Introduction

MIPI-DSI and LVDS

DART-MX8M-MINI SoC supports MIPI-DSI interface. DART-MX8M-MINI can be optionally equipped with SN65DSI84 MIPI-DSI to LVDS bridge.
DART-MX8M-MINI carrier board comes with LVDS connectors, so you can easily connect LVDS display.
Connecting MIPI-DSI display to DART-MX8M-MINI carrier board requires designing a custom connector.

Adding custom LVDS panel

DART-MX8M-MINI evaluation kit comes with 800x480 LCD panel. DART-MX8M-MINI DTS file was created with this panel in mind. To support your custom LVDS panel, you should make several modifications

Referencing custom panel in the DTS file

The following code references Variscite panel in arch/arm64/boot/dts/freescale/fsl-imx8mm-var-dart.dts under kernel source tree

	dsi_lvds_bridge: sn65dsi84@2c {
		compatible = "ti,sn65dsi83";
		reg = <0x2c>;
		ti,dsi-lanes = <1>;
		ti,lvds-format = <1>;
		ti,lvds-bpp = <24>;
		ti,width-mm = <154>;
		ti,height-mm = <87>;
		enable-gpios = <&gpio2 11 GPIO_ACTIVE_HIGH>;
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_lvds>;
		status = "okay";

		display-timings {
			lvds {
				clock-frequency = <33000000>;
				hactive = <800>;
				vactive = <480>;
				hback-porch = <40>;
				hfront-porch = <40>;
				vback-porch = <29>;
				vfront-porch = <13>;
				hsync-len = <48>;
				vsync-len = <3>;
				hsync-active = <0>;
				vsync-active = <0>;
				de-active = <1>;
				pixelclk-active = <0>;
			};
		};
        ...
        };

You should modify the "ti,dsi-lanes", "ti,lvds-format", "ti,lvds-bpp", "ti,width-mm", "ti,height-mm" and "display-timings" properties to match your panel specification and rebuild the DTB file.
To support a dual channel LVDS panel, please add "ti,lvds-channels = <2>".

Rotating the Weston display

To rotate the Weston display, edit /etc/xdg/weston/weston.ini.

For example, rotate the display 90 degrees:

[output]
name=DSI-1
transform=90

For more information, see the weston man pages:

@@ Line 1: / Line 1: @@
-<!-- Set release according to "release" parameter in URL and use RELEASE_SUMO_V1.0_DART-MX8M-MINI as default
+<!-- Set release according to "release" parameter in URL and use RELEASE_SUMO_V1.1_DART-MX8M-MINI as default
---> {{#vardefine:RELEASE_PARAM|{{#urlget:release|RELEASE_SUMO_V1.0_DART-MX8M-MINI}}}} <!--
+--> {{INIT_RELEASE_PARAM|RELEASE_SUMO_V1.1_DART-MX8M-MINI}}<!--
 --> {{#lst:Yocto_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
 --> {{#lst:B2QT_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
---> {{PageHeader|{{#var:HARDWARE_NAME}} Display}} {{DocImage|category1=Yocto|category2={{#var:HARDWARE_NAME}}}}[[Category:Debian]]__toc__
+--> {{#lst:Debian_Platform_Customization|{{#var:RELEASE_PARAM}}}} <!--
+--> {{PageHeader|{{#var:HARDWARE_NAME}} Display}} {{DocImage|category1=Yocto|category2=Debian}}[[Category:{{#var:HARDWARE_NAME}}]]__toc__
 = Introduction =
 == MIPI-DSI and LVDS  ==
@@ Line 15: / Line 16: @@
 == Referencing custom panel in the DTS file ==
-The following code references Variscite panel in arch/arm64/boot/dts/freescale/{{#var:DEFAULT_DTB}} under kernel source tree
+The following code references Variscite panel in arch/arm64/boot/dts/freescale/{{#replace:{{#var:DEFAULT_DTB}}|.dtb|.dts}} under kernel source tree
+{{#ifeq: {{#var:KERNEL_USE_COMMUNITY_DRV_SN65DSI83}}|true|
+<pre>
+	&panel_lvds {
+		compatible = "panel-lvds";
+		data-mapping = "jeida-24";
+		width-mm = <154>;
+		height-mm = <87>;
+		panel-timing {
+			clock-frequency = <39000000>;
+			hactive = <800>;
+			vactive = <480>;
+			hback-porch = <40>;
+			hfront-porch = <40>;
+			vback-porch = <29>;
+			vfront-porch = <13>;
+			hsync-len = <48>;
+			vsync-len = <3>;
+			hsync-active = <0>;
+			vsync-active = <0>;
+			de-active = <1>;
+			pixelclk-active = <0>;
+		};
+	};
+</pre>
+You should modify the "data-mapping", "width-mm", "height-mm" and "display-timings" properties to match your panel specification and rebuild the DTB file.
+|
 <pre>
 	dsi_lvds_bridge: sn65dsi84@2c {
@@ Line 54: / Line 83: @@
 You should modify the "ti,dsi-lanes", "ti,lvds-format", "ti,lvds-bpp", "ti,width-mm", "ti,height-mm" and "display-timings" properties to match your panel specification and rebuild the DTB file.<br>
 To support a dual channel LVDS panel, please add "ti,lvds-channels = <2>".
+}}
+= Rotating the Weston display =
+{{WESTON_DISPLAY_ROTATE}}

DART-MX8M-MINI Display: Difference between revisions