Re: [PATCH v2 1/2] dt-bindings: dwc2: Add bindings for new Ingenic SoCs.

From: H. Nikolaus Schaller
Date: Thu Apr 14 2022 - 13:18:52 EST


Hi,

> Am 14.04.2022 um 19:11 schrieb Zhou Yanjie <zhouyanjie@xxxxxxxxxxxxxx>:
>
> Hi,
>
> On 2022/4/14 下午6:00, H. Nikolaus Schaller wrote:
>>
>>> Am 14.04.2022 um 09:32 schrieb Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>:
>>>
>>> On 13/04/2022 21:30, H. Nikolaus Schaller wrote:
>>>> So we need "snps,dwc2" to get any driver match and I thought the "ingenic,jz4780-otg" is redundant.
>>>>
>>>> But maintainers convinced me to keep it as a dummy compatible in the .dtsi for potential future
>>>> specialization (which does not exist and seems not to be necessary).
>>> Isn't exactly the next patch 2/2 using such specialization?
>>>
>>>> Unless I can convince them
>>>> that this is never ever needed. Which is beyond my knowledge and almost everyone.
>>>>
>>>> So we can't remove the "snps,dwc2" here.
>>>>
>>>> Well, we can with more work elsewhere.
>>>> You have to extend the dwc2_of_match_table to include all ingenic devices.
>>>>
>>>> Therefore we now know 3 potential solutions:
>>>> a) remove "ingenic,jz4780-otg" from jz4780.dtsi (my proposal)
>>>> b) add "ingenic,jz4780-otg" to dwc2.yaml together with "snps,dwc2" (your proposal + my suggestion here)
>>>> c) add only "ingenic,jz4780-otg" to dwc2.yaml and extend the match table in drivers//usb/dwc2/params.c (new proposals)
>>>>
>>>> From consistency point of view I think variant b) is the right one. a) was rejected and c) only adds redundant code.
>>> c) was already proposed by Zhou, so if you think the code is not correct
>>> (the params for jz4780) maybe nack it there, so we will know that driver
>>> needs fixes.
>> Ah, ok. Now I see. I was just focussed on this patch and related dtbscheck
>> messages and did not read patch 2/2.
>>
>> Yes, looking at both, they are variant c). Sorry that I didn't see it earlier.
>
> It looks like we need a [3/3] to remove "snps,dwc2", which not only solves
> the dtbscheck complaining problem, but also doesn't affect normal use after
> removing "snps,dwc2".

Yes, that seems to be the right thing to do.

BR and thanks,
Nikolaus