[Intel-gfx] Questions about tripple display

[Daniel Vetter]

On Fri, Jul 13, 2012 at 5:59 PM, Guo Tang <guo.tang at sonoartis.com> wrote:
> Hi,
> Greetings!
>
> I have a system with GM 45 chip set. I want to have 3 displays: LVDS, VGA,
> and TV output. There is no need for
> them to show different contents. So only clone display is required. From GM
> 45 chip set spec, looks like only 2
> display ports can be active at the same time. Is it possible to modify
> driver to get 3 clone displays? Any suggestion
> to where in the driver/Kernel I can poke around would be appreciated.

This does not work, because both LVDS and TV run on a fixed clock
(which does not necessarily agree with the dotclock of the mode),
hence you can't clone them. At least not in all cases, and imo trying
to support such a configuration in more cases is wasted effort. If you
need to drive that many outputs, you're not in the market of a low-end
igd solution like gm45 imho.

Cheers, Daniel
-- 
Daniel Vetter
daniel.vetter at ffwll.ch - +41 (0) 79 364 57 48 - http://blog.ffwll.ch