Received-SPF: pass (google.com: domain of linux-kernel+bounces-86280-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
Date: Thu, 29 Feb 2024 09:21:07 +0100
From: Maxime Ripard <mripard@kernel.org>
To: "Klymenko, Anatoliy" <Anatoliy.Klymenko@amd.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>, 
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>, Thomas Zimmermann <tzimmermann@suse.de>, 
	David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>, 
	"Simek, Michal" <michal.simek@amd.com>, Andrzej Hajda <andrzej.hajda@intel.com>, 
	Neil Armstrong <neil.armstrong@linaro.org>, Robert Foss <rfoss@kernel.org>, Jonas Karlman <jonas@kwiboo.se>, 
	Jernej Skrabec <jernej.skrabec@gmail.com>, 
	"dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org>, 
	"linux-arm-kernel@lists.infradead.org" <linux-arm-kernel@lists.infradead.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 4/4] drm/atomic-helper: Add select_output_bus_format
 callback
Message-ID: <20240229-crane-of-eternal-joy-f675d7@houat>
References: <20240226-dp-live-fmt-v1-0-b78c3f69c9d8@amd.com>
 <20240226-dp-live-fmt-v1-4-b78c3f69c9d8@amd.com>
 <20240228-nifty-flashy-shrew-905edc@houat>
 <PH7PR12MB7163136599B97B071979E72EE6582@PH7PR12MB7163.namprd12.prod.outlook.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha512;
	protocol="application/pgp-signature"; boundary="rs5ri76nt4anyhzn"
Content-Disposition: inline
In-Reply-To: <PH7PR12MB7163136599B97B071979E72EE6582@PH7PR12MB7163.namprd12.prod.outlook.com>


--rs5ri76nt4anyhzn
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

Hi,

On Wed, Feb 28, 2024 at 10:00:19PM +0000, Klymenko, Anatoliy wrote:
> > > diff --git a/include/drm/drm_modeset_helper_vtables.h
> > > b/include/drm/drm_modeset_helper_vtables.h
> > > index 881b03e4dc28..7c21ae1fe3ad 100644
> > > --- a/include/drm/drm_modeset_helper_vtables.h
> > > +++ b/include/drm/drm_modeset_helper_vtables.h
> > > @@ -489,6 +489,37 @@ struct drm_crtc_helper_funcs {
> > >  				     bool in_vblank_irq, int *vpos, int *hpos,
> > >  				     ktime_t *stime, ktime_t *etime,
> > >  				     const struct drm_display_mode *mode);
> > > +
> > > +	/**
> > > +	 * @select_output_bus_format
> > > +	 *
> > > +	 * Called by the first connected DRM bridge to negotiate input media
> > > +	 * bus format. CRTC is expected to pick preferable media formats fr=
om
> > > +	 * the list supported by the DRM bridge chain.
> >=20
> > There's nothing restricting it to bridges here. Please rephrase this to=
 remove the
> > bridge mention. The user is typically going to be the encoder, and brid=
ges are just
> > an automagic implementation of an encoder.
> >=20
>=20
> OK. I'll fix than in the next version.
>=20
> > And generally speaking, I'd really like to have an implementation avail=
able before
> > merging this.
> >
>=20
> Well, 2 instances of this callback implementations exist as drafts, as
> this is the new API. A little bit of a chicken and egg problem. I'll
> try to groom at least one of them into upstreamable shape and attach
> it to the patch set.

That's totally what I meant :)

I basically don't want to have an interface that isn't used. If you
provide an implementation in the same series, it's totally reasonable

Maxime

--rs5ri76nt4anyhzn
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iHUEABYKAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCZeA+cgAKCRDj7w1vZxhR
xQLtAP9/fGoxq0DXjo7CwyIuSIvVRUO1zC+/mQvsS2T+X6Z0gQD/aTj1xrt+ImK+
u6CAeB4rSGry8XnZlOByE/CzK+HDXwM=
=dkG1
-----END PGP SIGNATURE-----

--rs5ri76nt4anyhzn--