[lkml]   [2000]   [Mar]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [linux-fbdev] fbdev 2.4.0 cleanups
James A Simmons writes:
> Okay lets consider this. Now some video cards use different apertures for
> their video memory. What I mean the framebuffer location is different for
> 8 bit (it's little endian) and 16 bit (big endian). Consider this.
> You start your X server in 8 bit mode. Now it will have write access to
> /dev/fb. Now you start some app which opens /dev/fb in read only mode and
> gets the current fix info. fix->smem_start will point to the little endian
> aperture right. Now your X server has properly ALT whatever function keys
> that do change the video mode. Since the X server has write access it can
> change the modes. So now you switch to 16 bit color mode which means
> fix->smem_start has changed to the big aperture. Your other app is still
> writing to where the little endian aperture was which is the wrong place.

Unless there has been a major change in X11, I don't think that's possible.
I believe that the only thing that Alt +/- can do is change resolution, not
colour depth.

IIRC, colour depth requires a restart of the server and all applications.

Please correct me if I'm wrong.
|_____| ------------------------------------------------- ---+---+-
| | Russell King --- ---
| | | | / / |
| +-+-+ --- -+-
/ | THE developer of ARM Linux |+| /|\
/ | | | --- |
+-+-+ ------------------------------------------------- /\\\ |

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:57    [W:0.277 / U:1.556 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site