xfbdev alpha channel

["Tabaro Toni" <tabarot@xxxxxxxxxx>]

Hi, i have succesfully cross-compiled the xfree 4.7.0 on a embedded board with mipsel processor and framebuffer on a 2.6.12 linux environment, with the framebuffer running at 960x1080x32 ARGB8888 or 1280x720x16 ARGB1555.

The Xfbdev program start and work (if i export a display on a i386 machine and start xclock the xclock program work).

The problem is: to see the image on the board i must run a program in background which set the alpha bit to 1 (on the 1280x720x16 ARGB 1555 frame buffer) or byte to 0xff (in the case of 960x1080x32 ARGB8888), otherwise the screen remains black.

I think the Xfbdev can't handle the alpha channel correctly, leaving it to 0.

I dont need the translucency or other features, only see the image on screen, maybe i can patch the framebuffer code to leave the alpha at fixed value, is someone able to help me by suggest the part of code to patch?

I searched on the programs/Xserver/hw/tinyx/fbdev/ or programs/Xserver/fb/ path, but i am not able to understand how the alpha is handled :-(

 

Thanks, Pierantonio.