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Message-ID: <1560243127.13886.3.camel@pengutronix.de>
Subject: Re: [PATCH v7 2/4] media: videodev2: add
 V4L2_FMT_FLAG_FIXED_RESOLUTION
From:   Philipp Zabel <p.zabel@pengutronix.de>
To:     Hans Verkuil <hverkuil@xs4all.nl>,
        Maxime Jourdan <mjourdan@baylibre.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Hans Verkuil <hans.verkuil@cisco.com>
Cc:     Kevin Hilman <khilman@baylibre.com>,
        Jerome Brunet <jbrunet@baylibre.com>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-amlogic@lists.infradead.org
Date:   Tue, 11 Jun 2019 10:52:07 +0200
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         <20190531093126.26956-3-mjourdan@baylibre.com>
         <9731b2db-efd4-87d0-c48d-87adec433747@xs4all.nl>
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On Wed, 2019-06-05 at 15:39 +0200, Hans Verkuil wrote:
> Hi Maxime,
> 
> I am wondering if this flag shouldn't be inverted: you set
> V4L2_FMT_FLAG_DYN_RESOLUTION if dynamic resolution is supported,
> otherwise it isn't.
> 
> Can all the existing mainlined codec drivers handle midstream
> resolution changes?
> 
> s5p-mfc, venus and mediatek can, but I see no SOURCE_CHANGE event in
> the coda drivers, so I suspect that that can't handle this.
> 
> Philipp, what is the status of the coda driver for dynamic resolution
> changes?

FTR, to my knowledge there is no dynamic resolution change support in
the firmware, as there is no signal (interrupt nor picture run return
value) to indicate that different headers were parsed.

I am planning to add the initial source change event required by the
current decoder API documentation, but I am afraid there will be no
support for source changes due to mid-stream resolution changes due to
firmware limitations.

regards
Philipp