[PATCH v3] dt-bindings: pinctrl: Convert Amlogic Meson pinctrl binding

Neil Armstrong narmstrong.kernel at gmail.com
Sat Feb 4 23:57:21 PST 2023


> Le 5 févr. 2023 à 01:05, Heiner Kallweit <hkallweit1 at gmail.com> a écrit :
> 
> On 04.02.2023 23:56, Martin Blumenstingl wrote:
>> Hi Heiner,
>> 
>> On Wed, Feb 1, 2023 at 11:13 PM Heiner Kallweit <hkallweit1 at gmail.com> wrote:
>> [...]
>>>>> +      - items:
>>>>> +          - const: amlogic,meson8m2-aobus-pinctrl
>>>>> +          - const: amlogic,meson8-aobus-pinctrl
>>>>> +      - items:
>>>>> +          - const: amlogic,meson8m2-cbus-pinctrl
>>>>> +          - const: amlogic,meson8-cbus-pinctrl
>>>> 
>>>> Again, can't have both with and without the fallback allowed.
>>>> 
>>> Hi Martin,
>>> 
>>> meson8m2 is the only chip version having a fallback for the
>>> pinctrl compatible. Is this fallback really needed?
>>> Looking at the driver it seems that both compatibles
>>> are handled identically.
>> Back in the day we decided to duplicate the Meson8 driver code just to
>> add four new pin functions that are added by the Meson8m2 SoC
>> generation:
>> "eth_rxd2", "eth_rxd3", "eth_txd2", "eth_txd3"
>> 
>> The compatible string was defined with a similar approach: since
>> Meson8m2 just adds a few bits to the Meson8 pin controller it's
>> backwards compatible.
>> 
>> If the fallback has to be removed then I'm okay with that but I would
>> like to understand it first.
>> So far I thought that Rob basically asked to remove the following two
>> compatible strings from the enum (as they're listed separately with
>> their fallbacks):
>> - amlogic,meson8m2-cbus-pinctrl
>> - amlogic,meson8m2-aobus-pinctrl
>> 
> Right, this should be sufficient. There's no place where the 8m2 pinctrl
> compatibles are used w/o fallback.
> 
> Then the hopefully final version of the binding is almost ready.
> I'm just still checking whether there's any way in yaml to specify
> a reg-names list with mandatory and optional names. Doesn't seem so.

It’s possible with minItems/maxItems and allOf:if/else to specify different min/max for each compatible

Neil

> 
>> 
>> Best regards,
>> Martin
> 
> Heiner



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