Re: [PATCH v2 01/13] spi: dt-bindings: cdns,qspi-nor: Add Renesas RZ/N1D400 to the list

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hello Geert,

>> --- a/Documentation/devicetree/bindings/spi/cdns,qspi-nor.yaml
>> +++ b/Documentation/devicetree/bindings/spi/cdns,qspi-nor.yaml
>> @@ -80,6 +80,10 @@ properties:
>>            # controllers are meant to be used with flashes of all kinds,
>>            # ie. also NAND flashes, not only NOR flashes.
>>            - const: cdns,qspi-nor
>> +      - items:
>> +          - const: renesas,r9a06g032-qspi
>> +          - const: renesas,rzn1-qspi
>> +          - const: cdns,qspi-nor
>
> Doesn't the need for (at least) the CQSPI_NO_INDIRECT_MODE flag mean
> that this device is not compatible with cdns,qspi-nor, and thus the
> cdns,qspi-nor fallback must not be used?

I understand the question. It is true that I use driver data to limit
the number of features the IP can use and this data is associated to the
Renesas compatible, but I believe all other flavours of this IP would
also not work without driver data attached to their front
compatible. None of the SoCs with the Cadence QSPI IP actually would run
without their own driver data. For me the fallback compatible is
relevant because it describes the hardware as "this is a derivative of
the Cadence controller" (and it is clearly the case, and this is also
mentioned in the reference manual), even though I agree using
cdns,qspi-nor would definitely not work alone. But again, none of the
other flavours would anyway.

Thanks,
Miquèl