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Date:   Mon, 3 Jul 2023 18:58:55 +0100
From:   Mark Brown <broonie@kernel.org>
To:     Hans Verkuil <hverkuil@xs4all.nl>
Cc:     Takashi Iwai <tiwai@suse.de>,
        Shengjiu Wang <shengjiu.wang@gmail.com>,
        Sakari Ailus <sakari.ailus@iki.fi>,
        Shengjiu Wang <shengjiu.wang@nxp.com>, tfiga@chromium.org,
        m.szyprowski@samsung.com, mchehab@kernel.org,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        Xiubo.Lee@gmail.com, festevam@gmail.com, nicoleotsuka@gmail.com,
        lgirdwood@gmail.com, perex@perex.cz, tiwai@suse.com,
        alsa-devel@alsa-project.org, linuxppc-dev@lists.ozlabs.org,
        Jacopo Mondi <jacopo@jmondi.org>
Subject: Re: [PATCH 1/6] media: v4l2: Add audio capture and output support
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On Mon, Jul 03, 2023 at 03:12:55PM +0200, Hans Verkuil wrote:

> My main concern is that these cross-subsystem drivers are a pain to
> maintain. So there have to be good reasons to do this.

> Also it is kind of weird to have to use the V4L2 API in userspace to
> deal with a specific audio conversion. Quite unexpected.

> But in the end, that's a decision I can't make.

> So I wait for that feedback. Note that if the decision is made that this
> can use V4L2, then there is quite a lot more that needs to be done:
> documentation, new compliance tests, etc. It's adding a new API, and that
> comes with additional work...

Absolutely, I agree with all of this - my impression was that the target
here would be bypass of audio streams to/from a v4l2 device, without
bouncing through an application layer.  If it's purely for audio usage
with no other tie to v4l2 then involving v4l2 does just seem like
complication.

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