Re: [PATCH v2 1/2] dt-bindings: can: renesas,rcar-canfd: Document renesas,fd-only property

[Krzysztof Kozlowski <krzk@kernel.org>]

On 23/11/2025 15:17, Biju Das wrote:
> Hi Krzysztof Kozlowski,
> 
>> -----Original Message-----
>> From: Biju Das
>> Sent: 23 November 2025 14:06
>> Subject: RE: [PATCH v2 1/2] dt-bindings: can: renesas,rcar-canfd: Document renesas,fd-only property
>>
>>
>>
>>> -----Original Message-----
>>> From: Krzysztof Kozlowski <krzk@kernel.org>
>>> Sent: 23 November 2025 13:26
>>> Subject: Re: [PATCH v2 1/2] dt-bindings: can: renesas,rcar-canfd:
>>> Document renesas,fd-only property
>>>
>>> On 23/11/2025 12:23, Biju wrote:
>>>> From: Biju Das <biju.das.jz@bp.renesas.com>
>>>>
>>>> The CANFD on RZ/{G2L,G3E} and R-Car Gen4 support 3 modes FD-Only
>>>> mode, Classical CAN mode and CAN-FD mode. In FD-Only mode,
>>>> communication in Classical CAN frame format is disabled. Document
>>>> renesas,fd-only to handle this mode. As these SoCs support 3 modes,
>>>> update the description of renesas,no-can-fd property and disallow it for R-Car Gen3.
>>>>
>>>> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
>>>> ---
>>>>  v1->v2:
>>>>   * Added conditional check to disallow fd-only mode for R-Car Gen3.
>>>> ---
>>>>  .../bindings/net/can/renesas,rcar-canfd.yaml  | 24
>>>> ++++++++++++++++---
>>>>  1 file changed, 21 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git
>>>> a/Documentation/devicetree/bindings/net/can/renesas,rcar-canfd.yaml
>>>> b/Documentation/devicetree/bindings/net/can/renesas,rcar-canfd.yaml
>>>> index f4ac21c68427..a52244f0b5d1 100644
>>>> ---
>>>> a/Documentation/devicetree/bindings/net/can/renesas,rcar-canfd.yaml
>>>> +++ b/Documentation/devicetree/bindings/net/can/renesas,rcar-canfd.y
>>>> +++ am
>>>> +++ l
>>>> @@ -125,9 +125,17 @@ properties:
>>>>    renesas,no-can-fd:
>>>>      $ref: /schemas/types.yaml#/definitions/flag
>>>>      description:
>>>> -      The controller can operate in either CAN FD only mode (default) or
>>>> -      Classical CAN only mode.  The mode is global to all channels.
>>>> -      Specify this property to put the controller in Classical CAN only mode.
>>>> +      The controller can operate in either CAN-FD mode (default) or FD-Only
>>>> +      mode (RZ/{G2L,G3E} and R-Car Gen4) or Classical CAN mode. Specify this
>>>> +      property to put the controller in Classical CAN mode.
>>>> +
>>>> +  renesas,fd-only:
>>>> +    $ref: /schemas/types.yaml#/definitions/flag
>>>> +    description:
>>>> +      The CANFD on RZ/{G2L,G3E} and R-Car Gen4 SoCs support 3 modes FD-Only
>>>> +      mode, Classical CAN mode and CAN-FD mode (default). In FD-Only mode,
>>>> +      communication in Classical CAN frame format is disabled. Specify this
>>>> +      property to put the controller in FD-Only mode.
>>>>
>>>>    assigned-clocks:
>>>>      description:
>>>> @@ -267,6 +275,16 @@ allOf:
>>>>        patternProperties:
>>>>          "^channel[6-7]$": false
>>>>
>>>> +  - if:
>>>> +      properties:
>>>> +        compatible:
>>>> +          contains:
>>>> +            enum:
>>>> +              - renesas,rcar-gen3-canfd
>>>> +    then:
>>>> +      properties:
>>>> +        renesas,fd-only: false
>>>> +
>>>
>>> You did not respond to my first paragraph from previous version. As I
>>> said, you now need oneOf to restrict these, since you are not using simple enum.
>>
>> This is restricting for R-Car Gen3. DT binding check returns error if 'renesas,fd-only"
>> is defined for R-Car Gen3.
>>
>> Am I missing anything here?

Add on G2L no-can-fd and fd-only. What do you see? What is expected?

Best regards,
Krzysztof