Configuring LVDS early during boot on T30

Technical Support
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1

I need to configure the GPIO-Pins early to be able to use the LVDS Interface to Display a Splashscreen. Configuring the needed pins in a linux service works, but happens to late to be useful for a splashscreen.
Next I tried to configure the pins in U-Boot by adding

gpio clear 216; gpio clear 219; gpio set 220; gpio set 221; gpio set 222; gpio clear 223; gpio clear 225; gpio set 226;

to the startscript, which enables the Display for a second until the Kernel is loaded. After bootup is complete we can verify that the GPIO-Pins have been reset to their default state.

Any Advice where/how we can set these GPIO-Pins early in the boot-process to be able to display a Splashscreen? Kernel Splash whould be fine

2

In the Linux kernel such pinmux configuration may be done here:

http://git.toradex.com/cgit/linux-toradex.git/tree/arch/arm/mach-tegra/board-apalis_t30-pinmux.c?h=tegra#n498

3

Thanks a lot for your quick reply! I had a look around in the folder and patched the file board-apalis_t30.c where i was easily able to find a struct defining the initial state of these GPIO pins by their name

4

Perfect. Thanks for the feedback.