Re: [PATCH v2 5/9] dt-bindings: iio: dac: add ad3552r axi-dac compatible

[Krzysztof Kozlowski <krzk@kernel.org>]

On 06/09/2024 11:11, Angelo Dureghello wrote:
> Hi Krzysztof,
> 
> On 06/09/24 9:22 AM, Krzysztof Kozlowski wrote:
>> On Thu, Sep 05, 2024 at 05:17:35PM +0200, Angelo Dureghello wrote:
>>> From: Angelo Dureghello <adureghello@baylibre.com>
>>>
>>> Add a new compatible for the ad3552r variant of the generic DAC IP.
>>>
>>> The ad3552r DAC IP variant is very similar to the generic DAC IP,
>>> register map is the same, but some register fields are specific to
>>> this IP, and also, a DDR QSPI bus has been included in the IP.
>>>
>>> Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
>>> ---
>>>   Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml | 1 +
>>>   1 file changed, 1 insertion(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml b/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml
>>> index a55e9bfc66d7..c0cccb7a99a4 100644
>>> --- a/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml
>>> +++ b/Documentation/devicetree/bindings/iio/dac/adi,axi-dac.yaml
>>> @@ -24,6 +24,7 @@ properties:
>>>     compatible:
>>>       enum:
>>>         - adi,axi-dac-9.1.b
>>> +      - adi,axi-dac-ad3552r
>> I am sorry, but what is the product here? It looks like either wrong
>> order or even completely redundant. What is ad3552r?
>>
>> And why versions are mixed with real products but without any
>> compatibility. What does the version express in such case?
> 
> dac-ad3552r IP (fpga) is a variant of the dac IP, very similar,
> about the version, it still reads as 9.1.b
> 
> so i can eventually change it to:
> 
> adi,axi-dac-ad3552-9.1.b
> 
> Should be more correct.

No. First ad3552r is the product, so axi-dac is redundant. Second why
adding versions if you have product names? Versioning was allowed
because apparently that's how these are called, but now it turns out it
is not version but names.

Third, versions are useless if you do not use them as fallbacks.

Something this is really broken and I don't know if the binding or this
patch.

Best regards,
Krzysztof