[Nouveau] [PATCH xf86-video-nouveau] Do not register hotplug without RandR

[Chris Wilson]

On Wed, Mar 29, 2017 at 07:03:12PM -0400, Ilia Mirkin wrote:
> Chris, could you have a look at this since it's allegedly your work in
> the intel driver and let us know if it's reasonable? I'm definitely
> not enough of an X driver guy to rule one way or the other.

Yup, it is from

commit 1a489142c8e6a4828348cc9afbd0f430d3b1e2d8
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Tue Oct 23 23:43:50 2012 +0100

    sna: Disable RandR hotplug events if Xinerama is enabled
    
    Since RandR itself is disabled if Xinerama is enabled, for example with
    ZaphodHeads, calling RRGetInfo() upon a hotplug event generates an
    assertion.
    
    Reported-by: Stephen Liang <inteldriver at angrywalls.com>
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=55260
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

and covers a quite obscure mix of features that results in no RandR.
Hmm, now with the link-status property there is a reason why the ddx
might want to handle hotplug even if it doesn't propagate the event on,
but so far link-status DP retraining in userspace is an i915.ko only
"feature".
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre