[PATCH v4 1/9] ASoC: dt-bindings: wcd938x: add bindings for wcd938x

[Srinivas Kandagatla]

Hi Rob,

On 15/04/2021 17:53, Srinivas Kandagatla wrote:
> Thanks Rob for quick review,
> 
> On 15/04/2021 17:29, Rob Herring wrote:
>> On Wed, Apr 14, 2021 at 04:48:37PM +0100, Srinivas Kandagatla wrote:
>>> Qualcomm WCD9380/WCD9385 Codec is a standalone Hi-Fi audio codec IC
>>> connected over SoundWire. This device has two SoundWire device RX and
>>> TX respectively, supporting 4 x ADCs, ClassH, Ear, Aux PA, 2xHPH,
>>> 7 x TX diff inputs, 8 DMICs, MBHC.
>>>
>>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla at linaro.org>
>>> ---
>>>   .../bindings/sound/qcom,wcd938x.yaml          | 176 ++++++++++++++++++
>>>   1 file changed, 176 insertions(+)
>>>   create mode 100644 
>>> Documentation/devicetree/bindings/sound/qcom,wcd938x.yaml
>>>
>>> diff --git 
>>> a/Documentation/devicetree/bindings/sound/qcom,wcd938x.yaml 
>>> b/Documentation/devicetree/bindings/sound/qcom,wcd938x.yaml
>>> new file mode 100644
>>> index 000000000000..4c8fa8290af0
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/sound/qcom,wcd938x.yaml
>>> @@ -0,0 +1,176 @@
> 
> ...
> 
>>> +additionalProperties: false
>>> +
>>> +examples:
>>> +  - |
>>> +    codec {
>>> +        compatible = "qcom,wcd9380-codec";
>>> +        reset-gpios = <&tlmm 32 0>;
>>> +        #sound-dai-cells = <1>;
>>> +        qcom,tx-device = <&wcd938x_tx>;
>>> +        qcom,rx-device = <&wcd938x_rx>;
>>> +        qcom,micbias1-microvolt = <1800000>;
>>> +        qcom,micbias2-microvolt = <1800000>;
>>> +        qcom,micbias3-microvolt = <1800000>;
>>> +        qcom,micbias4-microvolt = <1800000>;
>>> +        qcom,mbhc-hphl-switch;
>>> +        qcom,mbhc-ground-switch;
>>> +        qcom,mbhc-button0-vthreshold-microvolt = <75000>;
>>> +        qcom,mbhc-button1-vthreshold-microvolt = <150000>;
>>> +        qcom,mbhc-button2-vthreshold-microvolt = <237000>;
>>> +        qcom,mbhc-button3-vthreshold-microvolt = <500000>;
>>> +        qcom,mbhc-button5-vthreshold-microvolt = <500000>;
>>> +        qcom,mbhc-button6-vthreshold-microvolt = <500000>;
>>> +        qcom,mbhc-button7-vthreshold-microvolt = <500000>;
>>> +    };
>>> +
>>> +    /* ... */
>>> +
>>> +    soundwire at 3230000 {
>>> +        #address-cells = <2>;
>>> +        #size-cells = <0>;
>>> +        reg = <0x03230000 0x2000>;
>>> +        wcd938x_tx: codec at 0,3 {
>>> +            compatible = "sdw20217010d00";
>>> +            reg  = <0 3>;
>>> +            qcom,direction = "tx";
>>> +            qcom,port-mapping = <2 3 4 5>;
>>> +        };
>>> +
>>> +        wcd938x_rx: codec at 0,4 {
>>> +            compatible = "sdw20217010d00";
>>> +            reg  = <0 4>;
>>> +            qcom,direction = "rx";
>>> +            qcom,port-mapping = <1 2 3 4 5>;
>>> +        };
>>
>> This is a single device, right? We shouldn't need 3 nodes to describe
>> it. I think this should all be a single node like this:
>>
> No, WCD938x is a Audio Codec which has two SoundWire Slave device (TX 
> and RX). WCD938X reset lines and supplies are common for both TX and RX 
> SoundWire devices.
> 
> However TX SoundWire device only has register access to codec 
> CSR(Control Status registers).
> 
> So there are two SoundWire devices and a WCD938X common parts. Now 
> making the common Codec part as a separate device made more sense here.
> So we ended with total 3 devices.
> 
> 1 . WCD938x Codec which deals with all the codec side including Common 
> parts.
> 2. TX SoundWire device to configure TX SoundWire ports/interface and 
> provide CSR access.
> 3. RX SoundWire device to configure RX Soundwire ports/interface
> 


Are you okay with the existing device layout after providing the above 
information?


  codec {
         compatible = "qcom,wcd9380-codec";
         reset-gpios = <&tlmm 32 0>;
         #sound-dai-cells = <1>;
         qcom,tx-device = <&wcd938x_tx>;
         qcom,rx-device = <&wcd938x_rx>;
         qcom,micbias1-microvolt = <1800000>;
         qcom,micbias2-microvolt = <1800000>;
         qcom,micbias3-microvolt = <1800000>;
         qcom,micbias4-microvolt = <1800000>;
         qcom,mbhc-hphl-switch;
         qcom,mbhc-ground-switch;
         qcom,mbhc-button0-vthreshold-microvolt = <75000>;
         qcom,mbhc-button1-vthreshold-microvolt = <150000>;
         qcom,mbhc-button2-vthreshold-microvolt = <237000>;
         qcom,mbhc-button3-vthreshold-microvolt = <500000>;
         qcom,mbhc-button5-vthreshold-microvolt = <500000>;
         qcom,mbhc-button6-vthreshold-microvolt = <500000>;
         qcom,mbhc-button7-vthreshold-microvolt = <500000>;
     };


soundwire-controller at 3230000 {
     reg = <0 0x3230000 0 0x2000>;
     compatible = "qcom,soundwire-v1.5.1";
     wcd938x_tx: codec at 0,3 {
         compatible = "sdw20217010d00";
         reg  = <0 3>;
         qcom,direction = "tx";
         qcom,port-mapping = <2 3 4 5>;
     };
};


soundwire-controller at 3210000 {
     reg = <0 0x3210000 0 0x2000>;
     compatible = "qcom,soundwire-v1.5.1";
      wcd938x_rx: codec at 0,4 {
         compatible = "sdw20217010d00";
         reg  = <0 4>;
         qcom,direction = "rx";
         qcom,port-mapping = <1 2 3 4 5>;
     };
};


thanks,
srini


> 
>> codec at 0,3 {
>>          reg = <0 3>, <0 4>;
> 
> We can't have this, as these two SoundWire devices hang on different 
> SoundWire bus instances.
> 
>>     compatible = "sdw20217010d00";
>>
>>          reset-gpios = <&tlmm 32 0>;
>>          #sound-dai-cells = <1>;
>>          qcom,micbias1-microvolt = <1800000>;
>>          qcom,micbias2-microvolt = <1800000>;
>>          qcom,micbias3-microvolt = <1800000>;
>>          qcom,micbias4-microvolt = <1800000>;
>>          qcom,mbhc-hphl-switch;
>>          qcom,mbhc-ground-switch;
>>          qcom,mbhc-button0-vthreshold-microvolt = <75000>;
>>          qcom,mbhc-button1-vthreshold-microvolt = <150000>;
>>          qcom,mbhc-button2-vthreshold-microvolt = <237000>;
>>          qcom,mbhc-button3-vthreshold-microvolt = <500000>;
>>          qcom,mbhc-button5-vthreshold-microvolt = <500000>;
>>          qcom,mbhc-button6-vthreshold-microvolt = <500000>;
>>          qcom,mbhc-button7-vthreshold-microvolt = <500000>;
>> };
>>
>> You'll have to figure out the qcom,direction and qcom,port-mapping parts
>> though.
> 
> That is the reason why we ended up with 3 devices here.
> 
> --srini
>>
>> Rob
>>