Khadas DSI Display VIM4 Does not boot

VIM4
1

I have a khadas DSI display with the VIM4, but when I connect the cable the VIM4 does not boot. The display originally shipped with an incompatible cable for the VIM4, but I have ordered a new cable. Is there also a change to the display controller board that is necessary for the VIM4?

2

Looks like I may have connected the display cable backwards according to this image: https://docs.khadas.com/linux/images/vim4/vim4_ts050.jpg

After connecting and flashing the board with ubuntu gnome The board boots, but does not display anything on the MIPI DSI. Did I kill the display?

3

Messages from the kernel driver:

[   11.164670] lcd: lcd_ctrl: 0x00000086
[   11.165767] lcd: debug_ctrl: 0x00000000
[   11.167797] lcd: panel_type: edp_0
[   11.283416] lcd: [0]: driver version: 20220428(8-t7)
[   11.283623] lcd: [0]: detect mode: tablet, fr_auto_policy: 0, key_valid: 0
[   11.284303] lcd: lcd_clktree_probe
[   11.284737] lcd: [0]: status: 0, init_flag: 0
[   11.285308] lcd: [0]: lcd_gamma_check_en: 0
[   11.286325] lcd: [0]: lcd_get_config from dts
[   11.286476] lcd: [0]: edp_1080p, edp, 8bit, 1920x1080
[   11.339711] lcd: [0]: lcd_probe ok, init_state:0x1
[   11.340392] lcd: [1]: driver version: 20220428(8-t7)
[   11.345182] lcd: [1]: detect mode: tablet, fr_auto_policy: 0, key_valid: 0
[   11.345444] lcd: lcd_clktree_probe
[   11.347233] lcd: [1]: status: 0, init_flag: 0
[   11.347358] lcd: [1]: lcd_gamma_check_en: 0
[   11.347733] lcd: [1]: lcd_get_config from dts
[   11.348297] lcd: error: [1]: failed to get null
[   11.348852] lcd: error: [1]: probe exit
[   11.350909] lcd: [1]: lcd_probe failed
[   11.351009] mesonlcd: probe of fe018000.lcd1 failed with error -1
[   11.351597] lcd: [2]: driver version: 20220428(8-t7)
[   11.357819] lcd: [2]: detect mode: tablet, fr_auto_policy: 0, key_valid: 0
[   11.358098] lcd: error: lcd_clktree_probe_t7: clk dsi_host_gate
[   11.358819] lcd: error: lcd_clktree_probe_t7: clk dsi_phy_gate
[   11.359587] lcd: error: lcd_clktree_probe_t7: clk dsi_meas
[   11.360289] lcd: lcd_clktree_probe
[   11.365481] lcd: [2]: status: 0, init_flag: 0
[   11.365526] lcd: [2]: lcd_gamma_check_en: 0
[   11.366105] lcd: [2]: lcd_get_config from dts
[   11.366509] lcd: error: [2]: failed to get null
[   11.368184] lcd: error: [2]: probe exit
[   11.376270] lcd: [2]: lcd_probe failed
[   11.381177] mesonlcd: probe of fe018000.lcd2 failed with error -1
4

Hi @jschneck

The MIPI screen is not enabled at this moment, we are working on dual display now, we will release new image to support it in the future.

5

Thanks for the update @numbqq, does this also apply to the V-By-One connector as well?

6

I’d like to get to the root of this problem. Our use case for the Khadas VIM4 is to use as a dev kit while we produce a custom board using the A311D2. I was curious if the software components missing to enable dual display output were waiting on driver work from Amlogic? Thanks

7

AFAIK, HDMI + V-By-One dual screen is working on Android only at the moment.