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From:   Tomasz Figa <tfiga@chromium.org>
Date:   Tue, 9 Jul 2019 15:15:05 +0900
Message-ID: <CAAFQd5Cn9GzXEj+tBtJsL8GXouJEyj+HSUng5StqNsCxKZK9yw@mail.gmail.com>
Subject: Re: [PATCH v5] media: docs-rst: Document m2m stateless video decoder interface
To:     Alexandre Courbot <acourbot@chromium.org>
Cc:     Paul Kocialkowski <paul.kocialkowski@bootlin.com>,
        Maxime Ripard <maxime.ripard@bootlin.com>,
        Nicolas Dufresne <nicolas@ndufresne.ca>,
        Hans Verkuil <hverkuil@xs4all.nl>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Linux Media Mailing List <linux-media@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Thu, Jun 20, 2019 at 4:35 PM Alexandre Courbot <acourbot@chromium.org> wrote:
[snip]
> +Initialization
> +==============
> +
[snip]
> +5. *[optional]* Choose a different ``CAPTURE`` format than suggested via
> +   :c:func:`VIDIOC_S_FMT` on ``CAPTURE`` queue. It is possible for the client to
> +   choose a different format than selected/suggested by the driver in
> +   :c:func:`VIDIOC_G_FMT`.
> +
> +    * **Required fields:**
> +
> +      ``type``
> +          a ``V4L2_BUF_TYPE_*`` enum appropriate for ``CAPTURE``.
> +
> +      ``pixelformat``
> +          a raw pixel format.

We should be able to set different width and height as well, to allow
strided and padded frame buffers. Otherwise we wouldn't be able to
import DMA-bufs allocated from some other sources.

(FYI, I've posted a similar comment to the stateful interface too.)

Best regards,
Tomasz