[PATCH v1 2/2] drm/virtio: Add the hotplug_mode_update property for rescanning of modes

[Daniel Vetter]

On Fri, Jan 06, 2023 at 09:56:40AM +0100, Gerd Hoffmann wrote:
> On Thu, Nov 17, 2022 at 05:30:54PM -0800, Vivek Kasireddy wrote:
> > Setting this property will allow the userspace to look for new modes or
> > position info when a hotplug event occurs.
> 
> This works just fine for modes today.
> 
> I assume this is this need to have userspace also check for position
> info updates added by patch #1)?

What does this thing even do? Quick grep says qxl and vmwgfx also use
this, but it's not documented anywhere, and it's also not done with any
piece of common code. Which all looks really fishy.

I think we need to do a bit of refactoring/documenting here first.

Also in principle, userspace needs to look at everything in the connector
again when it gets a hotplug event. We do have hotplug events for specific
properties nowadays, but those are fairly new.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch