Dual-head config broke with update to 1.4.2

[Alex Deucher]

On Mon, Feb 15, 2010 at 5:24 PM, Martin Cracauer <cracauer at cons.org> wrote:
> Alex Deucher wrote on Mon, Feb 15, 2010 at 11:27:39AM -0500:
>> On Mon, Feb 15, 2010 at 11:14 AM, Martin Cracauer <cracauer at cons.org> wrote:
>> > Alex Deucher wrote on Mon, Feb 15, 2010 at 10:52:44AM -0500:
>> >> On Sun, Feb 14, 2010 at 6:51 PM, Martin Cracauer <cracauer at cons.org> wrote:
>> >> > I have a Thinkpad T41 with an internal LCD and a VGA out, using an
>> >> > older Radeon chip and the radeon Xorg driver. ?I have a display at the
>> >> > VGA out and have configured dual-head via ServerLayout. ?This broke
>> >> > with an update to Xorg 1.4.2.
>> >> >
>> >> > Short version:
>> >> > - I seem to select the wrong output between LVDS (LCD), VGA, DVI and
>> >> > ?TV. ?Instead of LVDS and VGA and I seem to get the (non-existent)
>> >> > ?DVI and VGA. ?As a result, when X11 is up it seems that screen-0
>> >> > ?disappeared and screen-1 (VGA) is now DISPLAY=:0.0. ?There is no
>> >> > ?:0.1.
>> > [...]
>> >> Your best bet is to switch to using xrandr to configure your card:
>> >> http://wiki.debian.org/XStrikeForce/HowToRandR12
>> >> It will let you dynamically switch between single and multi-head.
>> >
>> > No, that doesn't work for me. ?I need classic dualhead with separate
>> > $DISPLAY so that I have separate virtual desktop switching on each.
>> >
>> > I have seen that this works fine for the same Xorg version on other
>> > computers not using the Radeon/ATI driver.
>> >
>> > So I reported it to the ATI driver list (assuming my subscription went
>> > through).
>>
>> If you want to keep using zaphod mode, your best bet it to continue
>> using the old version of the driver.  New features like support for
>> more than two outputs cause problems with zaphod mode.
>
> But I don't want more than two outputs.
>

Most people want access to all the outputs supported by their cards.

> All I want is my working pre-1.4.x setup with internal LCD and VGA
> back.  I hope this is a misunderstanding.  I don't want any new
> feature.  Just my two old outputs just the way they were until I
> upgraded Xorg.
>
> In case this is actually broken now, can I use an old driver in the
> 1.4.x Xorg server or do I have to downgrade the whole server?

You should be able to use the pre-xrandr1.2 driver (xf86-video-ati
6.6.3) with xserver 1.4.x.

>
> In general I am a bit surprised that you dismiss non-xrandr dual-head
> so easily.  Apart from the fact that it worked until recently with
> your ATI driver and continues to work with other card's drivers the
> model of work and setup is entirely different between classic
> dual-head with two screens and xrandr.  There's no easy way for me to
> switch to any single-display dual-screen setup.

What other recent open source drivers does it work with?  Most, if not
all, xrandr 1.2 capable open source drivers have dropped zaphod
support.  I think radeon is the only one that even attempts to
continue to support it anymore.  It still works it just doesn't
provide a way to select which connectors you want to associate with
each instance of the driver.  The number of zaphod users is relatively
small and the amount of developer resources to support it is
relatively high.  More people want to be able to use and dynamically
switch between all their connectors than want to use zapod.

Alex

>
> Martin
> --
> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
> Martin Cracauer <cracauer at cons.org>   http://www.cons.org/cracauer/
> FreeBSD - where you want to go, today.      http://www.freebsd.org/
>