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Subject: Re: [PATCH 0/6] Initial Rust V4L2 support
From:   Nicolas Dufresne <nicolas.dufresne@collabora.com>
To:     Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Daniel Almeida <daniel.almeida@collabora.com>
Cc:     Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
        Hans Verkuil <hverkuil@xs4all.nl>, wedsonaf@gmail.com,
        ojeda@kernel.org, mchehab@kernel.org,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-media@vger.kernel.org, kernel@collabora.com,
        Sakari Ailus <sakari.ailus@iki.fi>
Date:   Mon, 01 May 2023 16:10:58 -0400
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Le mercredi 26 avril 2023 =C3=A0 20:25 +0300, Laurent Pinchart a =C3=A9crit=
=C2=A0:
> Hi Daniel,
>=20
> On Wed, Apr 26, 2023 at 06:14:33PM +0100, Daniel Almeida wrote:
> > Hi,
> >=20
> > As I said higher up on this thread, I can maintain the Rust bits and=
=20
> > help out with the issues around it.
> >=20
> > IMHO, we should at least try this. Who knows, it might work out :)
> >=20
> > Laurent, maybe we can take a piecemeal approach? Right now there are no=
=20
> > bindings for MC, but I wouldn't complain about fixing some of the C cod=
e=20
> > when the time comes.
>=20
> The lifetime issues affect plain V4L2 video nodes too I'm afraid :-)

Everything under the bindings is unsafe code, so it does not prevent doing =
upper
implementation and have other things be memory safe. It just make Rust less
helpful in some cases (I guess everything across ops).

There is low hanging fruit if some folks are interested. I see legitimate
benefit in rewriting in rust the JPEG parser, the H.264 reference list
generator, and maybe VP9 probability update lib. AV1 driver will need a lib=
 to
reduce duplicates, this could be done straight in Rust (offering a C interf=
ace
of course, so it does not matter if the users are written in rust or C).

Nicolas

>=20
> > Just FYI, I am writing some more bindings, just enough to write a=20
> > stateless decoder driver. I hope to finish it in time for the media=20
> > summit. It will give us a more in-depth idea of the pros and cons here.
>=20
> --=20
> Regards,
>=20
> Laurent Pinchart
>=20