Re: [PATCH 0/8] media: i2c: adv748x: add support for HDMI audio

From: Hans Verkuil <hverkuil-cisco@xs4all.nl>
To: Alex Riesen <alexander.riesen@cetitec.com>,
	Kieran Bingham <kieran.bingham@ideasonboard.com>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	devel@driverdev.osuosl.org, linux-media@vger.kernel.org,
	linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
	linux-renesas-soc@vger.kernel.org
Subject: Re: [PATCH 0/8] media: i2c: adv748x: add support for HDMI audio
Date: Fri, 13 Mar 2020 09:37:18 +0100	[thread overview]
Message-ID: <4ab3dd9f-26fb-ce38-170c-bba4b3777455@xs4all.nl> (raw)
In-Reply-To: <20200313083107.GB3832@pflmari>

On 3/13/20 9:31 AM, Alex Riesen wrote:
> Hi Hans,
> 
> Hans Verkuil, Fri, Mar 13, 2020 09:21:05 +0100:
>> As a general note for this series: it might be better to have two
>> patch series: one for patches 1 and 3-6 (not sure whether 5 can be included
>> or not), and one where the public API changes (i.e. new V4L2 audio controls)
>> are added. The first can probably be merged fairly quickly, the second will
>> likely require more iterations since public API patches always take much longer
>> before they are mature.
> 
> I see. After the discussion started, I started to have suspicions of my own
> regarding the V4L2 ioctls. Except for log-status, which is a practical
> diagnostics feature (even supported by v4l2-ctl), I'm thinking about dropping
> them altogether in favor of audio soc DAI implementation.
> The DAI implementation does all we ever needed from the device. Besides,
> selecting a I2S protocol variant from user space (I2S vs I2S/TDM) never felt
> right.

That sounds like what everyone else does as well.

> 
> Shall I submit the log-status separately?

Yes please. In my experience, log status is a very nice and very useful feature.

If you have other sensible cleanups, then feel free to add those as well.

Regards,

	Hans

> 
> Regards,
> Alex
> 
>> On 1/13/20 3:14 PM, Alex Riesen wrote:
>>> This adds minimal support for controlling the audio output I2S port available
>>> on ADV7481 and ADV7482 HDMI decoder devices by ADI. The port carries audio
>>> signal from the decoded HDMI stream.
>>>
>>> An ADV7482 on the Renesas Salvator-X ES1.1 was used during development of this
>>> code.
>>>
>>> Alex Riesen (8):
>>>  1. media: adv748x: add a device-specific wrapper for register block read
>>>  2. media: adv748x: add audio mute control and output selection ioctls
>>>  3. media: adv748x: add log_status ioctl
>>>  4. media: adv748x: reserve space for the audio (I2S) port in the driver
>>>     structures
>>>  5. media: adv748x: add an ASoC DAI definition to the driver
>>>  6. media: adv748x: reduce amount of code for bitwise modification of
>>>     device registers
>>>  7. dt-bindings: adv748x: add information about serial audio interface
>>>     (I2S/TDM)
>>>  8. arm64: dts: renesas: salvator: add a connection from adv748x codec
>>>     (HDMI input) to the R-Car SoC
>>>
>>>  .../devicetree/bindings/media/i2c/adv748x.txt |  13 +-
>>>  .../dts/renesas/r8a7795-es1-salvator-x.dts    |  24 +-
>>>  .../boot/dts/renesas/salvator-common.dtsi     |  35 +-
>>>  drivers/media/i2c/adv748x/adv748x-core.c      |  54 +++
>>>  drivers/media/i2c/adv748x/adv748x-hdmi.c      | 355 ++++++++++++++++++
>>>  drivers/media/i2c/adv748x/adv748x.h           |  53 ++-
>>>  6 files changed, 523 insertions(+), 11 deletions(-)
>>>