[PATCH 1/3] drm: add connector info/property for non-desktop displays

[Daniel Vetter]

On Wed, Oct 25, 2017 at 01:23:58PM -0700, Keith Packard wrote:
> Daniel Stone <daniel at fooishbar.org> writes:
> 
> > I still think putting these behind a client cap is a good idea:
> > https://lists.freedesktop.org/archives/dri-devel/2017-October/155616.html
> 
> Assuming that everyone eventually catches up, this should be a
> short-term issue. So, all we have to do is figure out how to make the
> transition, which seems a lot less weighty than something that will
> affect the environment for a long time.
> 
> We need to consider the cross-version compatibility issues for both the
> window system and the kernel. That means an old window system with new
> kernel or new window system with old kernel should work as well as it
> does today.
> 
> Today, an HMD display is presented as a normal output and applications
> can discover it through the window system and present an image on it by
> placing their image at the right location on the screen. To keep that
> working, we can't hide HMD outputs from an older window system.

Yeah we add flags when old userspace would get more broken by this. If
old/existing userspace is handling stuff incorrectly already, there's no
need to flag that it now works better, and hiding by default seems to have
issues too. In case of doubt I'll opt for less uapi, anytime that's
possible :-)

So my vote on no opt-in flag needed here.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch