[ltp] x41 monitor selection

Václav Štěpán linux-thinkpad@linux-thinkpad.org
Thu, 01 Mar 2007 03:32:49 +0100

Just short note:
With a bit older chipset (i855) on a R50e, it is definitely possible
to use both the LCD and the external display. However, there are
certain limitations:
a) Clone view mode - that is what the normal F4 switching did
   under for example DOS. Just the video runs only on one of the
   screens, if you use XVideo and not X11 driver (mplayer).
b) Xinerama - no hw OpenGL, if i attach the external LCD in suspended
   state (or in hibernation), the frequency and resolution get adapted
   to the connected LCD.
c) Dualhead OpenGL - in the dual-head setup without Xinerama I have
   DRI on the primary head and the external device is sensed via
   DevicePresence option in xorg.conf - when I attach the beamer
   and resume, I get a second head. Otherwise I have one, GL accelerated
d) Composite extension - I can get a fully accelerated desktop
   with Beryl on either the internal or external display. But
   just on one and I am unable to switch without X restart.

So I think that it is not really a driver problem, at least so long
as the GL works only for primary head.
(That's on Debian testing, xorg 7.1.)

Vaclav Stepan

Paul Fox napsal(a):
> i wrote:
>  > as a reminder, my problem is that using the fn-key to switch
>  > monitors on my X41 will give me either the external or the
>  > built-in display, but not both.  this is even though both
>  > displays work fine together when the X server first starts (or is
>  > restarted).
> as a final followup to this problem:  i got hold of the code for
> the i810 X11 driver module, and was able to do some debugging.  (the
> new modular drivers for X11 make this relatively painless).  after
> some back and forth with one of the developers, a fix will be going
> in to the next release...