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Subject: Re: [PATCH] media: rcar-vin: add G/S_PARM ioctls
To:     =?UTF-8?Q?Niklas_S=c3=b6derlund?= <niklas.soderlund@ragnatech.se>
Cc:     Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Vladimir Barinov <vladimir.barinov@cogentembedded.com>
References: <20210924084115.2340-1-nikita.yoush@cogentembedded.com>
 <YU2gSJKfsqP+gUci@oden.dyn.berto.se>
From:   Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Message-ID: <c90a960f-4c4d-7e9c-5f85-2931d1530550@cogentembedded.com>
Date:   Fri, 24 Sep 2021 16:48:29 +0300
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> I would like to ask your use-case for this. I'm trying to make up the
> courage to move Gen2 inline with Gen3, that is move Gen2 to use the
> media graph interface to allow it more complex use-cases, including
> controlling parameters on the subdevice level.
> 
> So I'm curious if this solve a particular problem for you or if it's
> done "just" for completeness. If it solves a real problem then I think
> we should move a head with a v2 (with the small comment below fixed) if
> not I would like to try and reduce the non media graph usage of the API
> as much as possible.

I believe parallel camera - such as ov5642 - connected to Kingfisher's parallel interface still has to 
be controlled over v4l operations on vin device. And, to control frame rate of such cameras [which is 
the usecase we have here at Cogent], the operations that this patch adds are requied.

> Please use &vin->vdev instead of video_devdata(file).

Preparing v2 now.

Nikita