[PATCH v3] linux-dmabuf: clarify DRM_FORMAT_MOD_INVALID

[Simon Ser]

On Wednesday, April 17, 2019 2:05 PM, Pekka Paalanen <ppaalanen at gmail.com> wrote:
> On Wed, 17 Apr 2019 05:45:41 +0000
> Simon Ser contact at emersion.fr wrote:
>
> > I think it would be good to clarify that the "format" event is not sent
> > in this version? And maybe make it a protocol error to send a
> > format/modifier combination that wasn't advertised?
>
> As I explained before, I wouldn't make the protocol error now, it's
> just more hassle. Compositors would still need to support v3 semantics
> when a client binds a v3. A note to fix this for when we break the ABI
> the next time is fine by me.
>
> I think the "format" event is already clear enough.
>
> What would be the benefit of implementing interface v4 across the board?

The guarantee that DRM_FORMAT_MOD_INVALID is sent by Mutter? But this
is arguably a Mutter bug.

> The v3 patch forgets to say the new rules apply to interface v4, which
> makes it look like they are retrofitted to all versions.

Yeah, I was waiting for more feedback before bringing this up. :)