Re: [PATCH v1 1/4] ASoC: dt-bindings: qcom,pm4125-codec: Add the MBHC jack properties

[Ajay Kumar Nandam <ajay.nandam@oss.qualcomm.com>]

On 10/15/2026 7:43 PM, Mohammad Rafi Shaik wrote:
> The binding already describes qcom,mbhc-buttons-vthreshold-microvolt,
> but not the rest of the data the MBHC block needs to detect a 3.5mm
> jack, even though wcd_dt_parse_mbhc_data() reads all of it from the
> codec node and the schema has unevaluatedProperties set to false. A
> board that describes its jack is therefore rejected by the schema.
> 
> Document the remaining four properties, matching the descriptions used
> for the same properties in qcom,wcd93xx-common.yaml:
> 
>   - qcom,hphl-jack-type-normally-closed and
>     qcom,ground-jack-type-normally-closed describe the board's jack
>     switches. The MBHC logic has to know the idle state of the HPHL and
>     ground switches to tell an insertion from a removal.
>   - qcom,mbhc-headset-vthreshold-microvolt and
>     qcom,mbhc-headphone-vthreshold-microvolt are the ADC thresholds that
>     separate a headset from a headphone and a headphone from a floating
>     jack. They are board specific because they depend on the jack
>     wiring and on the microphone bias voltage they are measured against.
> 
> All four stay optional, as they are for the wcd93xx codecs: the driver
> derives the thresholds from the microphone bias voltage when they are
> absent and assumes normally open switches, so existing device trees
> keep working unchanged.
> 
> Assisted-by: Claude Opus 5
> Signed-off-by: Mohammad Rafi Shaik <mohammad.rafi.shaik@oss.qualcomm.com>
> ---
>   .../devicetree/bindings/sound/qcom,pm4125-codec.yaml   | 18 ++++++++++++++++++
>   1 file changed, 18 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/sound/qcom,pm4125-codec.yaml b/Documentation/devicetree/bindings/sound/qcom,pm4125-codec.yaml
> index 6e2f103be..54e5b7607 100644
> --- a/Documentation/devicetree/bindings/sound/qcom,pm4125-codec.yaml
> +++ b/Documentation/devicetree/bindings/sound/qcom,pm4125-codec.yaml
> @@ -64,6 +64,24 @@ properties:
>       minimum: 1800000
>       maximum: 2850000
>   
> +  qcom,hphl-jack-type-normally-closed:
> +    description: Indicates that HPHL jack switch type is normally closed
> +    type: boolean
> +
> +  qcom,ground-jack-type-normally-closed:
> +    description: Indicates that Headset Ground switch type is normally closed
> +    type: boolean
> +
> +  qcom,mbhc-headset-vthreshold-microvolt:
> +    description: Voltage threshold value for headset detection
> +    minimum: 0
> +    maximum: 2850000
> +
> +  qcom,mbhc-headphone-vthreshold-microvolt:
> +    description: Voltage threshold value for headphone detection
> +    minimum: 0
> +    maximum: 2850000
> +
>     qcom,mbhc-buttons-vthreshold-microvolt:
>       description:
>         Array of 8 Voltage threshold values corresponding to headset

The binding documents 8 button thresholds, but looking at the PM4125
register definitions I only see threshold registers for BTN0 through 
BTN4. The following registers are MICB2_RAMP, MBHC_CTL_1 and MBHC_CTL_2.

Am I missing how thresholds for buttons 5-7 are programmed here, or 
should PM4125 only expose 5 button thresholds?

Thanks & Regards
Ajay kumar Nandam

>