Re: [PATCH RFC v2 2/6] ASoC: dt-bindings: qcom,sm8250: Add clocks properties for I2S

[Srinivas Kandagatla <srini@kernel.org>]

On 10/9/25 3:03 PM, Neil Armstrong wrote:
> On 10/9/25 15:36, Srinivas Kandagatla wrote:
>>
>>
>> On 10/8/25 7:56 PM, Neil Armstrong wrote:
>>> In order to describe the block and master clock of each I2S bus, add
>>> the first 5 I2S busses clock entries.
>>>
>>> The names (primary, secondary, tertiarty, quaternary, quinary, senary)
>>> uses the LPASS clock naming which were used for a long time on Qualcomm
>>> LPASS firmware interfaces.
>>>
>>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
>>> ---
>>>   .../devicetree/bindings/sound/qcom,sm8250.yaml      | 21 ++++++++++
>>> +++++++++++
>>>   1 file changed, 21 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml
>>> b/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml
>>> index
>>> 8ac91625dce5ccba5c5f31748c36296b12fac1a6..d1420d138b7ed8152aa53769c4d495e1674275e6 100644
>>> --- a/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml
>>> +++ b/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml
>>> @@ -64,6 +64,27 @@ properties:
>>>       $ref: /schemas/types.yaml#/definitions/string
>>>       description: User visible long sound card name
>>>   +  clocks:
>>> +    minItems: 2
>>> +    maxItems: 12
>>> +
>>> +  clock-names:
>>> +    minItems: 2
>>> +    items:
>>> +      # mclk is the I2S Master Clock, mi2s the I2S Bit Clock
>>> +      - const: primary-mi2s
>>> +      - const: primary-mclk
>>> +      - const: secondary-mi2s
>>> +      - const: secondary-mclk
>>> +      - const: tertiary-mi2s
>>> +      - const: tertiary-mclk
>>> +      - const: quaternary-mi2s
>>> +      - const: quaternary-mclk
>>> +      - const: quinary-mi2s
>>> +      - const: quinary-mclk
>>> +      - const: senary-mi2s
>>> +      - const: senary-mclk
>>> +
>>
>> I don't this is correct way to handling bitclk and mclks for I2S, these
>> are normally handled as part of snd_soc_dai_set_sysclk() transparently
>> without need of any device tree description.
>>
>> Also doing this way is an issue as this is going to break existing Elite
>> based platforms, and the device description should not change across
>> these both audio firmwares.
> 
> This is only for AudioReach platforms, on those platforms the
> clocks are registered in DT and are not accessible by the card.
> 
Clocks will be acessable via snd_soc_dai_set_sysclk ->
q6prm_set_lpass_clock once set_sysclk support is added to q6apm-lpass
i2s dai ops.


> Device description is obviously different for the AudioReach platforms.

Why should it be different, its same device.
We have platforms that use both Elite and Audioreach.

--srini
> 
> Neil
> 
>>
>> thanks,
>> Srini
>>
>>>   patternProperties:
>>>     ".*-dai-link$":
>>>       description:
>>>
>>
>