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Subject: Re: [RFC PATCH v6 02/11] media: v4l2: Extend pixel formats to unify
 single/multi-planar handling (and more)
From:   Nicolas Dufresne <nicolas@ndufresne.ca>
To:     Hsia-Jun Li <Randy.Li@synaptics.com>
Cc:     mchehab@kernel.org, hans.verkuil@cisco.com,
        laurent.pinchart@ideasonboard.com, sakari.ailus@iki.fi,
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        narmstrong@baylibre.com, linux-kernel@vger.kernel.org,
        frkoenig@chromium.org, stanimir.varbanov@linaro.org,
        tfiga@chromium.org, Hans Verkuil <hverkuil@xs4all.nl>,
        linux-media@vger.kernel.org
Date:   Tue, 15 Nov 2022 10:57:59 -0500
In-Reply-To: <3b1edf81-bcc0-0b56-7e55-93da55d7f747@synaptics.com>
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         <708221e8-a805-c394-6958-6c7ec24bfe66@synaptics.com>
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Le vendredi 11 novembre 2022 =C3=A0 11:03 +0800, Hsia-Jun Li a =C3=A9crit=
=C2=A0:
> There are four modifiers in DRM while we would only one in these patches.
> =C2=A0From the EGL
> https://registry.khronos.org/EGL/extensions/EXT/EGL_EXT_image_dma_buf_imp=
ort_modifiers.txt
>=20
> The modifier for echo plane could be different. I wish it would be=20
> better to create a framebuffer being aware of which planes are graphics=
=20
> or metadata.

I was told that having different modifiers per plane is not supported and j=
ust
an historical artifact of an over-engineered API design.

Nicolas