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

[Heiner Kallweit]

On 05.02.2023 08:57, Neil Armstrong wrote:
> 
>> 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
> 
I have a problem here because reg-names is in the gpio-controller child node and compatible is in the
pinctrl parent node. An expression under patternProperties doesn't see the compatible property of the
parent node. It would have been better to place regs/reg-names in the pinctrl node.
Not sure how to deal with this. The easiest would be to just have minItems:2 and maxItems:5 as criteria
for regs and reg-names.