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Date:   Sat, 09 Apr 2022 14:43:57 +0100
From:   Paul Cercueil <paul@crapouillou.net>
Subject: Re: [PATCH 07/18] MIPS: DTS: jz4780: fix otg node as reported by
 dtbscheck
To:     "H. Nikolaus Schaller" <hns@goldelico.com>
Cc:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
        linux-mips@vger.kernel.org, letux-kernel@openphoenux.org
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Le sam., avril 9 2022 at 15:37:51 +0200, H. Nikolaus Schaller=20
<hns@goldelico.com> a =E9crit :
>=20
>=20
>>  Am 09.04.2022 um 15:23 schrieb Krzysztof Kozlowski=20
>> <krzysztof.kozlowski@linaro.org>:
>>=20
>>  On 09/04/2022 15:18, H. Nikolaus Schaller wrote:
>>  hould have a specific compatible.
>>>>>  Please mention why it does not.
>>>>=20
>>>>  Agreed. The "snps,dwc2" should be a fallback string, otherwise=20
>>>> there is no way to uniquely identify the JZ4780 implementation of=20
>>>> the IP.
>>>=20
>>>  Well, there is no specifc implementation and driver for it. So no=20
>>> need to uniquely identify it.
>>=20
>>  Specific implementation and driver are not arguments here. This=20
>> does not
>>  matter. It's really unrelated argument.
>=20
> The argumentation is in reverse: if there is no need for a=20
> specialized driver or implementation,
> why is there is a need to define a specialization.
>=20
> Your argument was:
> "there is no way to uniquely identify the JZ4780 implementation of=20
> the IP"
>=20
> My question is:
> "what do we need that for?"

You may not need the differenciation now, but if you need it in the=20
future and you had only the "snps,dwc2" compatible previously, then=20
you're screwed, since your driver must support older device tree blobs.

-Paul

>>  Bindings are not about implementation in Linux. Implementation can
>>  change, so bindings should also?
>=20
> No. Implementations should be agnostic.
>=20