Touchscreen turns white after raspberry update

ARCH_T

Hi,
After updating the raspberry pi ("sudo apt-get update") the touchscreen turns white. Any solution to solve this?
Touchscreen: velleman vmp400 (3.5" 320 x 480)
Raspberry Pi 4B

Thanks in Advance
Best Regards,
Tiago Sousa

Repetier

My guess is that you changed back a config to some original settings with the update. So first try running the screen installation steps you did when you first configured the screen.

On next update then watch out if debian offers to install the original configuration for some services.

ARCH_T

Repetier wrote
My guess is that you changed back a config to some original settings with the update. So first try running the screen installation steps you did when you first configured the screen.

On next update then watch out if debian offers to install the original configuration for some services.

Thanks for your response. I tried the screen installation again, in the same way (and other ways) but it doesn't work :(

Repetier

Did you also tell xserver to use the new screen instead. I think it was in a file of fbturbo that you needed to change it to /dev/fb1 so it uses that and nit the hdmi output,

ARCH_T

No, it doesn't work. The problem happens when the raspberry pi does the upgrade (not the update). I think it could be an incompatibility or something wrong with the new version :(

Repetier

Maybe. I noticed that the kernel is now 5.4 and not 4.19 so maybe the display drivers were for the old kernel. I'm not enough into this kernel stuff to say if that is a problem or not.