[PATCH 2/4] dt-bindings: net: dsa: document internal MDIO bus

[Arınç ÜNAL]

On 13.08.2023 15:59, Arınç ÜNAL wrote:
> On 13.08.2023 14:53, Vladimir Oltean wrote:
>> On Sat, Aug 12, 2023 at 10:20:43PM +0300, Arınç ÜNAL wrote:
>>> diff --git a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
>>> index 4d5f5cc6d031e2..82dda8fae8b16e 100644
>>> --- a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
>>> +++ b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
>>> @@ -72,6 +72,10 @@ properties:
>>>             - compatible
>>>             - reg
>>> +  mdio:
>>> +    $ref: dsa.yaml#/properties/mdio
>>> +    unevaluatedProperties: false
>>
>> sja1105 does not support an "mdio" child property. I haven't checked the
>> others. Don't add properties that aren't supported.
> 
> Adding the mdio property to the dsa.yaml schema will allow it on all of the
> schemas that refer to dsa.yaml such as this one. This addition here is only
> to disallow additional properties under the mdio property for this specific
> schema.
> 
> That said, my understanding is that the internal MDIO bus exists on all of
> the switches controlled by DSA. Whether each individual DSA subdriver
> supports registering it does not matter in terms of documenting the
> internal MDIO bus for all DSA switches.

On top of this, I'd argue to document the internal MDIO bus on the
ethernet-switch.yaml schema instead.

Arınç

> 
> SJA1110 uses the mdios property instead because it's got two internal mdio
> buses, which is why I invalidate the mdio property for it. If SJA1105 has
> also got two internal mdio buses, let me know.
> 
>>
>>> +
>>>   patternProperties:
>>>     "^(ethernet-)?ports$":
>>>       patternProperties:
>>>
>>> The nxp,sja1105.yaml schema also needed some changes.
>>>
>>> dt-bindings: net: dsa: nxp,sja1105: improve internal MDIO bus bindings
>>>
>>> SJA1110 Ethernet Switch uses the mdios property for its internal MDIO bus.
>>> Therefore, disallow the mdios property for SJA1105, and the mdio property
>>> for SJA1110.
>>>
>>> Require the phy-handle property on the non-CPU ports if the mdios property
>>> is being used.
>>>
>>> Refer to dsa.yaml#/properties/mdio to point the human readers to the
>>> description on the dsa.yaml schema.
>>>
>>> ---
>>>   .../bindings/net/dsa/nxp,sja1105.yaml         | 20 ++++++++++++++++++-
>>>   1 file changed, 19 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
>>> index 82dda8fae8b16e..7d92350f1065b2 100644
>>> --- a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
>>> +++ b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
>>> @@ -52,7 +52,7 @@ properties:
>>>       patternProperties:
>>>         "^mdio@[0-1]$":
>>> -        $ref: /schemas/net/mdio.yaml#
>>> +        $ref: dsa.yaml#/properties/mdio
>>>           unevaluatedProperties: false
>>>           properties:
>>> @@ -128,14 +128,32 @@ allOf:
>>>       then:
>>>         properties:
>>>           spi-cpol: false
>>> +        mdios: false
>>> +
>>>         required:
>>>           - spi-cpha
>>>       else:
>>>         properties:
>>>           spi-cpha: false
>>> +        mdio: false
>>> +
>>>         required:
>>>           - spi-cpol
>>> +  - if:
>>> +      required: [ mdios ]
>>> +    then:
>>> +      patternProperties:
>>> +        "^(ethernet-)?ports$":
>>> +          patternProperties:
>>> +            "^(ethernet-)?port@[0-9]+$":
>>> +              if:
>>> +                not:
>>> +                  required: [ ethernet ]
>>> +              then:
>>> +                required:
>>> +                  - phy-handle
>>
>> For sja1105, phylink-compatible bindings (phy-handle, fixed-link or managed)
>> are required for all ports (user, dsa or cpu).
>>
>> Also, sja1105 does not populate the slave_mii_bus, so it never uses the
>> fallback where ports implicitly connect to an internal PHY if no phylink
>> bindings are present.
> 
> I'll handle these accordingly with your answer to my question above.
> 
> Arınç