Re: [PATCH] dt-bindings: usb: dwc2: document the port when usb-role-switch is used

[Fabrice Gasnier <fabrice.gasnier@foss.st.com>]

On 10/26/21 10:38 PM, Rob Herring wrote:
> On Wed, Oct 13, 2021 at 06:53:46PM +0200, Fabrice Gasnier wrote:
>> Document the "port" property, which is used with "usb-role-switch"
>> to describe the bus connector.
>> Definition is inspired from mediatek,mtu3.yaml.
>>
>> This fixes some errors seen when running "make dtbs_check":
>> ... 'port' does not match any of the regexes: 'pinctrl-[0-9]+'
>>         From schema: ... Documentation/devicetree/bindings/usb/dwc2.yaml
>>
>> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
>> ---
>>  Documentation/devicetree/bindings/usb/dwc2.yaml | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/dwc2.yaml b/Documentation/devicetree/bindings/usb/dwc2.yaml
>> index 10c7d9b..7d1aa53 100644
>> --- a/Documentation/devicetree/bindings/usb/dwc2.yaml
>> +++ b/Documentation/devicetree/bindings/usb/dwc2.yaml
>> @@ -130,6 +130,16 @@ properties:
>>      description: If present indicates that we need to reset the PHY when we 
>>        detect a wakeup. This is due to a hardware errata.
>>  
>> +  port:
>> +    description:
>> +      Any connector to the data bus of this controller should be modelled
>> +      using the OF graph bindings specified, if the "usb-role-switch"
>> +      property is used. See graph.txt
> 
> Drop 'See graph.txt'
> 
>> +    $ref: /schemas/graph.yaml#/properties/port
>> +
>> +dependencies:
>> +  port: [ 'usb-role-switch' ]
> 
> usb-role-switch without port is valid or both must be present. In case 
> of the latter, you need to add:

Hi Rob,

Thanks for your review.
I agree with your statement. But I miss something in this proposal:

> 
> usb-role-switch: [ port ]

I tried this without success, when running dt_binding_check.

For testing, I added locally in the example successively:

1 - usb-role-switch (alone)
-----
+        usb-role-switch;
"dwc2.example.dt.yaml: usb@101c0000: 'port' is a dependency of
'usb-role-switch'

2 - port without usb-role-switch
-----
+        //usb-role-switch;
+
+        port {
+          usb_role_sw: endpoint {
+            remote-endpoint = <&hs_ep>;
+          };
+        };
dt_binding_check is happy here. But it shouldn't, right ?

3 - both (port + usb-role-switch)
-----
dt_binding_check is ok.


But it seems functional, with
+ dependencies:
+   port: [ usb-role-switch ]
Shall I keep (without quotes) ?
With this, above statement, (changes in example) seems correctly
validated with dt_binding_check.

1 - dt_binding_check is happy
2 - usb@101c0000: 'usb-role-switch' is a dependency of 'port'
    (as expected ?)
3 - dt_binding_check is happy

I'll send a v2 with the other changes you propose.
Please review it there.

Best Regards,
Fabrice

> 
> Also, you don't need quotes.
> 
>> +
>>  required:
>>    - compatible
>>    - reg
>> -- 
>> 2.7.4
>>
>>