How to interface LVDS dIsplay on Jetson TK1?

Autonomous Machines Jetson & Embedded Systems Jetson TK1
1

Hi^^

i want use lvds display on jetson tk1.

now works: hardware connection complete & kernel modify.

i hope to your help.
sorry, i verry poor english.

current works is below.

< lvds lcd display >

  • Company: SHARP
  • Product name : LQ123K1LG03
  • Screen size : 1280(H) x 480(V)
  • Aspect ratio : 8:3

< Hardware Connection >

J3A1-25: +VDD_MUX (Main 12v from jack) --------------------- Inverter 12v
J3A1-26: GND ----------------------------------------------------- Inverter GND

J3A1-16: +3.3V_SYS (Main 3.3v supply) ------------------------ Vcc
J3A1-15: GND ----------------------------------------------------- GND
J3A1-31: LVDS_TXD0_P ------------------------------------------ Receiver signal CH0 (+)
J3A1-33: LVDS_TXD0_N ------------------------------------------ Receiver signal CH0 (-)
J3A1-34: LVDS_TXD1_P ------------------------------------------ Receiver signal CH1 (+)
J3A1-36: LVDS_TXD1_N ------------------------------------------ Receiver signal CH1 (-)
J3A1-40: LVDS_TXD2_P ------------------------------------------ Receiver signal CH2 (+)
J3A1-42: LVDS_TXD2_N ------------------------------------------ Receiver signal CH2 (-)
J3A1-37: LVDS_TXD3_P ------------------------------------------ Receiver signal CH3 (+)
J3A1-39: LVDS_TXD3_N ------------------------------------------ Receiver signal CH3 (-)
J3A1-45: LVDS_TXD4_P ------------------------------------------ Receiver signal CLK (+)
J3A1-43: LVDS_TXD4_N ------------------------------------------ Receiver signal CLK (-)

< Kernel Modify >

reference: [issue] LVDS panel enabled effect HDMI out image pull down menu items

modify .config file
enable CONFIG_TEGRA_LVDS
disable CONFIG_TEGRA_DP

2

< current ubuntu status >

ubuntu@tegra-ubuntu:~$ DISPLAY=:0 xrandr -q
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 1920 x 1200, current 1920 x 1200, maximum 1920 x 1200
default connected 1920x1200+0+0 0mm x 0mm
1920x1200 60.0*

3

I don’t believe anyone’s been able to get this to work as yet, here’s a thread which was never concluded with a working solution: https://devtalk.nvidia.com/default/topic/730349/embedded-systems/display-port-expansion-on-jetson-tk1/1/

EDIT: Actually, I think someone did get a panel working, but was having software-related issues with the GUI, IIRC. I don’t think they posted a how-to though.

4

Hello
Does LVDS can work on lastest version R21.4?
I saw SW feature document and detail thread that only HDMI+eDP supported.

http://developer.download.nvidia.com/embedded/L4T/r21_Release_v4.0/Tegra_Linux_Driver_Package_SW_Features_R21.4.pdf

https://devtalk.nvidia.com/default/topic/730349/embedded-systems/display-port-expansion-on-jetson-tk1/5/

5

Hi,

LVDS is not supported on jetson tk1 yet. It is under planning now. By default, HDMI is the primary display on jetson tk1. Are you using LVDS as the primary display in your use case?

6

Hello,

Tegra K1 supports HDMI, LVDS, eDP and MIPI DSI displays. And HDMI is working good in Jetson board. So, out of other three displays (LVDS, eDP and MIPI DSI), can anyone please confirm, what are the displays currently supported/tested in R21.4 release package?

Hello lkh,

You said LVDS is not currently supported and it is under planning. Is this official information from Nvidia and if so, is there any planned date for the LVDS support integration in next release package?

Thanks.

7

LVDS is not supported from the L4T side. I don’t know about MIPI DSI, but eDP is the direction for both TK1 and TX1 (there should be at least partial eDP support in the kernel already…or at least configurable).

8

Hello linuxdev,

Do you any information about Nvidia’s plan of supporting LVDS displays in future release?

Also, when googling, it seems that someone has already enabled LVDS display successfully in TK1. Please refer the following link:

http://askubuntu.com/questions/604264/nvidia-jetson-tk1lvds-panel-enabled-effect-hdmi-out-image-pull-down-menu-items

I am also trying to get LVDS display working in Jetson board but I am getting lot of issues in clocks and power-up sequence. I wonder how come the person in above mentioned link has successfully enabled LVDS in TK1.

Thanks

9

So far as I know, L4T has some eDP support, but no plans for old-style LVDS on the software side. Over time I would expect eDP to evolve, but LVDS will get left behind. This doesn’t mean LVDS isn’t possible, but means someone will probably need to step up for old style LVDS to work. There is some LVDS work already in the kernel, but it doesn’t seem to be tailored towards Jetson…I suspect kernel code tweaks were required for any success.