Title: Debian on JWS3288 (RK3288) - LCD stays black, everything else works [Print This Page] Author: cesarromero Time: yesterday 03:38 Title: Debian on JWS3288 (RK3288) - LCD stays black, everything else works Hi everyone,
I have a JWS3288 industrial board (Rockchip RK3288). It originally ran Android with the LCD working fine. I installed Debian 10 (image RK3288-Debian10-20231108.095729.img) using RKDevTool.
Everything works: SSH, network, Wi-Fi. But the LCD stays completely black, no backlight visible.
In software everything looks OK:
- /dev/fb0 exists (1024x768) and accepts writes
- DRM binds correctly (VOP + LVDS)
- Backlight sysfs reports bl_power=0, brightness=255
- LCD regulators are enabled
But physically the panel is off. Writing to /dev/fb0 shows nothing, not even a faint image with a flashlight.
My guess: the DTB in this Debian image is generic (probably Firefly-RK3288) and doesn't match the actual panel/backlight GPIO/PWM mapping of the JWS3288.
Has anyone gotten Debian working on a similar industrial RK3288 board? Any tips on how to extract or adapt the DTB from the original Android ROM?
Author: 1winbizpk Time: 5 hour before
Have you checked the display connector and the backlight driver? On Rockchip boards running Debian, the LCD backlight is often controlled by a PWM GPIO that needs to be explicitly enabled in the device tree. Try running cat /sys/class/backlight/brightness to see if the backlight node exists ¡ª if it does, writing a non-zero value should turn it on.
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