Re: [RFC PATCH net-next 1/9] dt-bindings: net: dsa: convert ksz bindings document to yaml

Florian Fainelli
2020-10-22T19:17:32Z

On 10/22/20 5:37 AM, Vladimir Oltean wrote:
> On Thu, Oct 22, 2020 at 12:54:52PM +0200, Kurt Kanzenbach wrote:
>> On Wed Oct 21 2020, Florian Fainelli wrote:
>>> On 10/21/2020 5:16 PM, Vladimir Oltean wrote:
>>>> On Wed, Oct 21, 2020 at 08:52:01AM +0200, Kurt Kanzenbach wrote:
>>>>> On Mon Oct 19 2020, Christian Eggers wrote:
>>>>> The node names should be switch. See dsa.yaml.
>>>>>
>>>>>> + compatible = "microchip,ksz9477";
>>>>>> + reg = <0>;
>>>>>> + reset-gpios = <&gpio5 0 GPIO_ACTIVE_LOW>;
>>>>>> +
>>>>>> + spi-max-frequency = <44000000>;
>>>>>> + spi-cpha;
>>>>>> + spi-cpol;
>>>>>> +
>>>>>> + ports {
>>>>>
>>>>> ethernet-ports are preferred.
>>>>
>>>> This is backwards to me, instead of an 'ethernet-switch' with 'ports',
>>>> we have a 'switch' with 'ethernet-ports'. Whatever.
>>>
>>> The rationale AFAIR was that dual Ethernet port controllers like TI's
>>> CPSW needed to describe each port as a pseudo Ethernet MAC and using
>>> 'ethernet-ports' as a contained allowed to disambiguate with the 'ports'
>>> container used in display subsystem descriptions.
>>
>> Yes, that was the outcome of previous discussions.
>
> And why would that disambiguation be necessary in the first place? My
> understanding is that the whole node path provides the necessary
> namespacing to avoid the confusion. For example, the 'reg' property
> means 100 things to 100 buses, and no one has an issue with that. I am
> not expecting an Ethernet switch to have an HDMI port, I might be wrong
> though.

The disambiguation is more of a hint given to DT analysis tools to
validate a given node with little to no knowledge of the containing
node. I don't really have a dog in the fight here.
--
Florian