Re: [PATCH v3] dt-bindings: gpio: add common consumer GPIO lines

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 01/04/2022 15:13, Rob Herring wrote:
> On Fri, 01 Apr 2022 09:27:14 +0200, Krzysztof Kozlowski wrote:
>> Typical GPIO lines like enable, powerdown, reset or wakeup are not
>> documented as common, which leads to new variations of these (e.g.
>> pwdn-gpios).  Add a common schema which serves also as a documentation
>> for preferred naming.
>>
>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>
>> ---
>>
>> Changes since v2:
>> 1. Correct email.
>>
>> Changes since v1:
>> 1. Select-true, add maxItems and description for each entry (Rob).
>> 2. Mention ACTIVE_LOW in bindings description (Linus).
>> 3. Add allOf for pwrseq reset-gpios case.
>>
>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>> ---
>>  .../bindings/gpio/gpio-consumer-common.yaml   | 64 +++++++++++++++++++
>>  1 file changed, 64 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/gpio/gpio-consumer-common.yaml
>>
> 
> My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
> on your patch (DT_CHECKER_FLAGS is new in v5.13):
> 
> yamllint warnings/errors:
> 
> dtschema/dtc warnings/errors:
> /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/regulator/richtek,rt4801-regulator.example.dt.yaml: rt4801@73: enable-gpios: [[4294967295, 2, 0], [4294967295, 3, 0]] is too long
> 	From schema: /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/gpio/gpio-consumer-common.yaml
> 

Hi Rob,

With v1, you proposed to use maxItems for all these standard gpios, but
as we see here there are two exceptions:
1. pwrseq might have up to 32 reset-gpios,
2. richtek,rt4801 uses up to 2 enable-gpios.

One way is to add exceptions in gpio-consumer-common.yaml, like I did
for reset-gpios and pwrseq. However this scales poor if more of such
usages appear.

Maybe let's drop the maxItems for all of them?

Best regards,
Krzysztof