Re: [PATCH v13 6/8] media: dt-bindings: wave5: add Chips&Media 521c codec IP support

From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To: Sebastian Fricke <sebastian.fricke@collabora.com>,
	Rob Herring <robh@kernel.org>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	NXP Linux Team <linux-imx@nxp.com>,
	Conor Dooley <conor+dt@kernel.org>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Jackson Lee <jackson.lee@chipsnmedia.com>,
	Hans Verkuil <hverkuil@xs4all.nl>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Shawn Guo <shawnguo@kernel.org>,
	Philipp Zabel <p.zabel@pengutronix.de>,
	Nas Chung <nas.chung@chipsnmedia.com>,
	Fabio Estevam <festevam@gmail.com>,
	linux-media@vger.kernel.org, Tomasz Figa <tfiga@chromium.org>,
	linux-kernel@vger.kernel.org,
	Nicolas Dufresne <nicolas.dufresne@collabora.com>,
	kernel@collabora.com, Robert Beckett <bob.beckett@collabora.com>,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	Darren Etheridge <detheridge@ti.com>
Subject: Re: [PATCH v13 6/8] media: dt-bindings: wave5: add Chips&Media 521c codec IP support
Date: Sun, 22 Oct 2023 18:01:31 +0200	[thread overview]
Message-ID: <3d465d3c-386d-467b-87e9-806962464ac5@linaro.org> (raw)
In-Reply-To: <20231021120526.eqe3esyxyi5b3e5d@basti-XPS-13-9310>

On 21/10/2023 14:05, Sebastian Fricke wrote:
> Hey Rob and Krzysztof,
> 
> On 16.10.2023 08:47, Rob Herring wrote:
>> On Thu, Oct 12, 2023 at 03:24:12PM +0200, Krzysztof Kozlowski wrote:
>>> On 12/10/2023 13:01, Sebastian Fricke wrote:
>>>> From: Robert Beckett <bob.beckett@collabora.com>
>>>>
>>>> Add bindings for the chips&media wave5 codec driver
>>>>
>>>> Signed-off-by: Robert Beckett <bob.beckett@collabora.com>
>>>> Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
>>>> Signed-off-by: Sebastian Fricke <sebastian.fricke@collabora.com>
>>>> ---
>>>>  .../devicetree/bindings/media/cnm,wave5.yaml       | 60 ++++++++++++++++++++++
>>>>  1 file changed, 60 insertions(+)
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/media/cnm,wave5.yaml b/Documentation/devicetree/bindings/media/cnm,wave5.yaml
>>>> new file mode 100644
>>>> index 000000000000..b31d34aec05b
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/media/cnm,wave5.yaml
>>>> @@ -0,0 +1,60 @@
>>>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>>>> +%YAML 1.2
>>>> +---
>>>> +$id: http://devicetree.org/schemas/media/cnm,wave5.yaml#
>>>
>>> Filename matching compatible, so: cnm,cm521c-vpu.yaml
> 
> With which compatible should the filename match? (see below)
> And just to be sure, this means that I rename the file to:
> `.../devicetree/bindings/media/cnm,wave521c.yaml`

With the fallback compatible.

> 
>>>
>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>> +
>>>> +title: Chips&Media Wave 5 Series multi-standard codec IP
>>>> +
>>>> +maintainers:
>>>> +  - Nas Chung <nas.chung@chipsnmedia.com>
>>>> +  - Jackson Lee <jackson.lee@chipsnmedia.com>
>>>> +
>>>> +description:
>>>> +  The Chips&Media WAVE codec IP is a multi format video encoder/decoder
>>>> +
>>>> +properties:
>>>> +  compatible:
>>>> +    enum:
>>>> +      - cnm,cm521c-vpu
>>>
>>> Can this device be anything else? Why VPU suffix?
>>
>> It needs an SoC specific compatible (TI something...) as well (or
>> instead). Unless there's a public spec with details on how many
>> clocks, resets, interrupts, etc. there are.
> 
> Okay so how about this, a bit similar to the Coda driver supplying both
> a general option and a SoC specific version:

Can generic compatible be used alone in board designs? If it is licensed
block, then most likely you want a fallback.

> 
> properties:
>    compatible:
>      enum:
>        - ti,k3-j721sX-wave521c
>        - cnm,wave521c
> 
> (ti,k3-j721sX-wave521c = manufacturer,SoC-codec)
> (tested on j721s2 but should work on other variations as well)
> 
> Another alternative could be: ti,k3-wave521c (less specific on a single
> SoC series but connected to a bigger range of devices)

Best regards,
Krzysztof