DART-6UL/VAR-SOM-MX7 Display: Difference between revisions

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= LVDS boot arguments =
= LVDS boot arguments =


== Resistive/Capacitive alternate screen ==
== Introduction ==
 
The i.MX6UL has an RGB controller. We added SN75LVDS83B RGB to LVDS bridge on the custom board.
Variscite expand the default display settings to support alternate display without any requirement to change the device tree. During the boot sequence Variscite u-boot will add screen_alternate=yes option to enable selection of the second display settings (capacitive display).<br>
For example:
<pre>
U-Boot # printenv mmcargs
mmcargs=setenv bootargs console=${console},${baudrate} ${smp} video=mxcfb1:off root=${mmcroot}
screen_alternate=yes
</pre>
The developer can prevent the modification of u-boot by settings var_auto_fdt_file=N.
<pre>
U-Boot # setenv var_auto_fdt_file=N
</pre>


== Switching to LVDS1 as main display ==
== Switching to LVDS1 as main display ==

Revision as of 10:08, 28 December 2015

DART-6UL- LVDS

LVDS boot arguments

Introduction

The i.MX6UL has an RGB controller. We added SN75LVDS83B RGB to LVDS bridge on the custom board.

Switching to LVDS1 as main display

Switching to LVDS1 display requires changing the "primary" of the lvds section flag in the device tree. Setting display to be LVDS1 by default: edit arch/arm/boot/dts/imx6qdl-var-som.dtsi and set section of the lvds1. When you set the "primary" property to the LVDS1 struct, make sure you remove it from the LVDS0 struct

lvds-channel@1 {
fsl,data-mapping = "spwg";
fsl,data-width = <18>;
crtc = "ipu1-di1";
primary;
status = "okay";
display-timings {
native-mode = <&timing1>;
timing1: hsd100pxn1 {
clock-frequency = <35714000>;
hactive = <800>;
vactive = <480>;
hback-porch = <28>;
hfront-porch = <17>;
vback-porch = <13>;
vfront-porch = <20>;
hsync-len = <20>;
vsync-len = <13>;
};
};
};

Please take a look on the wiki section for kernel out of tree to see how to compile the device tree.