I've used Yocto dora to build a kernel (3.0.35 4.1.0 modified wandboard kernel) and filesystem (fsl-image-gui) for a custom board based on the i.MX6S. When I run a Qt application on the board using startx ./my_application, the application runs but the screen is black. Certain widgets will show once they are updated (ie. if I click on a checkbox), but everything else is black.
I tried modifying xorg.conf to use Driver "fbdev" instead of Driver "vivante", but then when I run the application I get an error saying no screens found.
Does anyone know what could cause this?
As a sanity check, your Xorg.conf should match one of the following cases:
1) Vivante driver:
I would also recommend that you check /var/log/Xorg.0.log to see if there were any initialization errors that occurred at startup.
Thanks Justin, I've tried both of those xorg.conf configurations. The first one gives me a blank screen (except for the mouse cursor), and the second one displays the app but the screen is corrupted when a new window is shown or the display is rotated.
Xorg.0.log does not show any errors. There are a few warnings about missing fonts but that's it.
Ok I've been able to make some progress by adding xf86-video-fbdev to the bitbake image. However now I have 2 new problems:
1. When video is played back, there are red dots that flicker in and out all over the screen (I'm using Gstreamer).
2. When I try to rotate the screen 180 degrees using <Option "Rotate" "CW"> in xorg.conf, there are black lines through the screen.
Can anyone help with these problems?