i.MX 8QuadMax LVDS-HDMI output no signal from J2/J3

[Shao]

Hello everyone, 

I face some problem about HDMI output.

I connected the LVDS to HDMI adapter to J2, but the display always no signal. I already take one day to survey the solution.

I only find a related solution at https://community.nxp.com/t5/i-MX-Processors/HDMI-Output-in-i-MX-8QuadMax/td-p/1087406

Although the kernel version are a little different, I change the fdt_file to the corresponding file, imx8qm-mek.dtb.

It still doesn't work.

At the end, I try to change the plug. I find something weird.

I can get the output from J7/J8 plug, but i can't get the ouput from J2/J3 plug.

Information about setting

Board: i.MX8 QuadMax MEK

Linux Kernel version:Linux -2.2.0+g5ec03d06f54e #1 SMP PREEMPT Thu Sep 24 06:58:12 UTC 2020 aarch64 aarch64 aarch64 GNU/Linux

Uboot version:- U-Boot 2020.04-5.4.47-2.2.0+gffc3fbe7e5

dts:fdt_file=imx8qm-mek.dtb

Is there new change in imx8qmmek 5.4.47 ?

[joanxie]

have you tried the other bsp version demo images? do you mean older bsp can support this, but only 5.4.47 couldn't ? do you mind testing other version? let me test it on imx8qm board too

[Shao]

I try the other vision, the situation are the same. It still can't get the output from J2/J3.

Linux imx8qmmek 4.19.35-1.1.0+g0f9917c56d59 #1 SMP PREEMPT Wed Oct 30 13:09:11 UTC 2019 aarch64 aarch64 aarch64 GNU/Linux Linux imx8qmmek 4.14.62-imx_4.14.62_1.0.0_beta+g1907fe4 #1 SMP PREEMPT Tue Oct 16 06:33:37 UTC 2018 aarch64 aarch64 aarch64 GNU/Linux

[joanxie · Accepted solution]

I checked that imx8qm doesn't use lvds0_ch1 and lvds1_ch1 when you use single mode,  if you use split mode, these two ports can be used