Received-SPF: pass (google.com: domain of linux-kernel+bounces-88254-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1;
Date: Fri, 1 Mar 2024 11:30:56 +0100
From: Maxime Ripard <mripard@kernel.org>
To: Sebastian Wick <sebastian.wick@redhat.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>, 
	Thomas Zimmermann <tzimmermann@suse.de>, David Airlie <airlied@gmail.com>, 
	Daniel Vetter <daniel@ffwll.ch>, Jonathan Corbet <corbet@lwn.net>, 
	Sandy Huang <hjc@rock-chips.com>, Heiko =?utf-8?Q?St=C3=BCbner?= <heiko@sntech.de>, 
	Chen-Yu Tsai <wens@csie.org>, Jernej Skrabec <jernej.skrabec@gmail.com>, 
	Samuel Holland <samuel@sholland.org>, Hans Verkuil <hverkuil@xs4all.nl>, 
	Ville =?utf-8?B?U3lyasOkbMOk?= <ville.syrjala@linux.intel.com>, dri-devel@lists.freedesktop.org, 
	linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, 
	linux-media@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-sunxi@lists.linux.dev, 
	Dave Stevenson <dave.stevenson@raspberrypi.com>
Subject: Re: [PATCH v7 21/36] drm/connector: hdmi: Add Broadcast RGB property
Message-ID: <20240301-light-impressive-grasshopper-adabeb@houat>
References: <20240222-kms-hdmi-connector-state-v7-0-8f4af575fce2@kernel.org>
 <20240222-kms-hdmi-connector-state-v7-21-8f4af575fce2@kernel.org>
 <20240229194726.GB166694@toolbox>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable
In-Reply-To: <20240229194726.GB166694@toolbox>

On Thu, Feb 29, 2024 at 08:47:26PM +0100, Sebastian Wick wrote:
> > @@ -1708,6 +1731,39 @@ EXPORT_SYMBOL(drm_connector_attach_dp_subconnect=
or_property);
> >  /**
> >   * DOC: HDMI connector properties
> >   *
> > + * Broadcast RGB (HDMI specific)
> > + *      Indicates the Quantization Range (Full vs Limited) used. The c=
olor
> > + *      processing pipeline will be adjusted to match the value of the
> > + *      property, and the Infoframes will be generated and sent accord=
ingly.
> > + *
> > + *      This property is only relevant if the HDMI output format is RG=
B. If
> > + *      it's one of the YCbCr variant, it will be ignored and the outp=
ut will
> > + *      use a limited quantization range.
>=20
> Uh, maybe just say that the quantization range is selected automatically
> in case a YCbCr output format is in use. I'm not sure every YCbCr
> variant requires limited and even if it does, new formats could change
> this.

I documented what i915 is doing:
https://elixir.bootlin.com/linux/latest/source/drivers/gpu/drm/i915/display=
/intel_hdmi.c#L2143

Maxime