[PATCH] modes: Force output modes for manually enabled heads

[Aaron Plattner]

On Thu, Oct 08, 2009 at 10:09:20AM -0700, Keith Packard wrote:
> Excerpts from Chris Wilson's message of Thu Oct 08 09:43:16 -0700 2009:
> > In a headless configuration, in order to convince the XServer to start
> > the user must explicitly enable an output.
> 
> I see that as the fundemental problem here. I'd suggest that the
> server should allow the device to start without any outputs connected
> and create a default sized frame buffer (1024x768?).

For boards that actually have output connectors (i.e. not Tesla cards),
this is a bad idea.  The number of users who actually want a headless
configuration is much smaller than the number of users who would be
confused and infuriated when starting X makes all of their displays go
blank due to misconfiguration or driver bugs and results in what is
essentially a hung machine.

X failing to start with an informative log message is far better than a
frozen computer that requires the reset button to fix.  I think making
people explicitly configure X to be headless is a reasonable compromise.

-- Aaron