Re: [PATCH v7 2/4] media: videodev2: add V4L2_FMT_FLAG_FIXED_RESOLUTION

From: Philipp Zabel
Date: Tue Jun 11 2019 - 04:56:45 EST

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.