[alsa-devel] [PATCH v3 6/6] ASoC: qdsp6: dt-bindings: Add q6afe pcm dt binding documentation

[Adam Serbinski]

On 2020-02-12 04:59, Srinivas Kandagatla wrote:
> On 12/02/2020 01:52, Adam Serbinski wrote:
>> This patch adds documentation of bindings required for PCM ports on 
>> AFE.
>> 
>> Signed-off-by: Adam Serbinski <adam at serbinski.com>
>> CC: Andy Gross <agross at kernel.org>
>> CC: Mark Rutland <mark.rutland at arm.com>
>> CC: Liam Girdwood <lgirdwood at gmail.com>
>> CC: Patrick Lai <plai at codeaurora.org>
>> CC: Banajit Goswami <bgoswami at codeaurora.org>
>> CC: Jaroslav Kysela <perex at perex.cz>
>> CC: Takashi Iwai <tiwai at suse.com>
>> CC: alsa-devel at alsa-project.org
>> CC: linux-arm-msm at vger.kernel.org
>> CC: devicetree at vger.kernel.org
>> CC: linux-kernel at vger.kernel.org
>> ---
>>   .../devicetree/bindings/sound/qcom,q6afe.txt  | 42 
>> +++++++++++++++++++
>>   1 file changed, 42 insertions(+)
>> 
>> diff --git a/Documentation/devicetree/bindings/sound/qcom,q6afe.txt 
>> b/Documentation/devicetree/bindings/sound/qcom,q6afe.txt
>> index d74888b9f1bb..6b1b17d31a2a 100644
>> --- a/Documentation/devicetree/bindings/sound/qcom,q6afe.txt
>> +++ b/Documentation/devicetree/bindings/sound/qcom,q6afe.txt
>> @@ -51,6 +51,24 @@ configuration of each dai. Must contain the 
>> following properties.
>>   	Definition: Must be list of serial data lines used by this dai.
>>   	should be one or more of the 0-3 sd lines.
>>   + - qcom,pcm-quantype
>> +	Usage: required for pcm interface
>> +	Value type: <u32>
>> +	Definition: PCM quantization type
>> +		0 - ALAW, no padding
>> +		1 - MULAW, no padding
>> +		2 - Linear, no padding
>> +		3 - ALAW, padding
>> +		4 - MULAW, padding
>> +		5 - Linear, padding
>> +
>> + - qcom,pcm-slot-mapping
>> +	Usage: required for pcm interface
> 
> Are these not specific to 8k and 16k mode ?
> We should probably list values for both modes here.

No, this is just the offset that the audio sample is placed in with 
respect to a maximum of 4 slots, 16 bits wide, beginning with the sync 
pulse.

When switching between 8 and 16k sample rate, it is just the sync pulse 
rate that is changed. The audio sample will be delivered in the same 
slot, just at a different frequency.


>> +	Value type: <prop-encoded-array>
>> +	Definition: Slot mapping for audio channels. Array size is the 
>> number
>> +		of slots, minimum 1, maximum 4. The value is 0 for no mapping
>> +		to the slot, or the channel number from 1 to 32.
>> +
>>    - qcom,tdm-sync-mode:
>>   	Usage: required for tdm interface
>>   	Value type: <prop-encoded-array>
>> @@ -174,5 +192,29 @@ q6afe at 4 {
>>   			reg = <23>;
>>   			qcom,sd-lines = <1>;
>>   		};
>> +
>> +		pri-pcm-rx at 105 {
>> +			reg = <105>;
>> +			qcom,pcm-quantype = <2>;
>> +			qcom,pcm-slot-mapping = <1>;
>> +		};
>> +
>> +		pri-pcm-tx at 106 {
>> +			reg = <106>;
>> +			qcom,pcm-quantype = <2>;
>> +			qcom,pcm-slot-mapping = <1>;
>> +		};
>> +
>> +		quat-pcm-rx at 111 {
>> +			reg = <111>;
>> +			qcom,pcm-quantype = <5>;
>> +			qcom,pcm-slot-mapping = <0 0 1>;
>> +		};
>> +
>> +		quat-pcm-tx at 112 {
>> +			reg = <112>;
>> +			qcom,pcm-quantype = <5>;
>> +			qcom,pcm-slot-mapping = <0 0 1>;
>> +		};
>>   	};
>>   };
>>