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Date: Wed, 6 Dec 2017 16:08:14 +0100 (CET)
From: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
cc: linux-media@vger.kernel.org, Hans Verkuil <hverkuil@xs4all.nl>
Subject: Re: [PATCH 3/3 v7] uvcvideo: add a metadata device node
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Hi Laurent,

While testing the new patch version, we did introduce a couple of 
differences:

1. We cannot (easily) reuse .vidioc_querycap() - the metadata node uses 
v4l2_fh_open() directly, so, it has a different struct file::private_data 
pointer.

2. After your video device unification, the order has swapped: now 
/dev/video0 is a metadata node and /dev/video1 is a video node. Is that 
how you wanted to have this or you don't mind or shall I swap them back? 
For now I've swapped them back, I think that would be more appropriate.

Thanks
Guennadi