Re: [PATCH v3 2/3] ASoC: codecs: add new pm4125 audio codec driver

[Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>]

On 9/8/25 4:26 PM, Alexey Klimov wrote:
> Hi Srini,
> 
> On Fri Aug 15, 2025 at 4:36 PM BST, Srinivas Kandagatla wrote:


>>> +static int pm4125_codec_enable_rxclk(struct snd_soc_dapm_widget *w, struct snd_kcontrol *kcontrol,
>>> +				     int event)
>>> +{
>>> +	struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
>>> +
>>> +	switch (event) {
>>> +	case SND_SOC_DAPM_PRE_PMU:
>>>
>>> +static const struct snd_kcontrol_new pm4125_snd_controls[] = {
>>> +	SOC_SINGLE_EXT("HPHL_COMP Switch", SND_SOC_NOPM, 0, 1, 0,
>>
>>     SOC_SINGLE_EXT("HPHL_COMP Switch", PM4125_COMP_L, 0, 1, 0, ?
>>
>>> +		       pm4125_get_compander, pm4125_set_compander),
>>> +	SOC_SINGLE_EXT("HPHR_COMP Switch", SND_SOC_NOPM, 1, 1, 0,
>>
>>        SOC_SINGLE_EXT("HPHR_COMP Switch", PM4125_COMP_R, 1, 1, 0,?
>>
>>> +		       pm4125_get_compander, pm4125_set_compander),
>>
>> This is same issue in one of the WCD codec, which am going to send fixes
>> along with my original wcd fixes series.
> 
> So this was in other codecs for years, right?

only in wcd937x since it was added.

> 
>>> +
>>> +	SOC_SINGLE_TLV("HPHL Volume", PM4125_ANA_HPHPA_L_GAIN, 0, 20, 1,
>>> +		       line_gain),
>>> +	SOC_SINGLE_TLV("HPHR Volume", PM4125_ANA_HPHPA_R_GAIN, 0, 20, 1,
>>> +		       line_gain),
...
                          PM4125_ANA_HPHPA_FSM_DIV_RATIO_MASK,
>>                                       PM4125_ANA_HPHPA_FSM_DIV_RATIO_68);
>> @@ -309,8 +307,6 @@ static int pm4125_rx_clk_disable(struct
>> snd_soc_component *component)
>>         snd_soc_component_write_field(component,
>> PM4125_DIG_SWR_CDC_RX_CLK_CTL,
>>                                       PM4125_DIG_SWR_ANA_RX_CLK_EN_MASK,
>>                                       PM4125_DIG_SWR_RX_CLK_DISABLE);
>> -       pm4125_global_mbias_disable(component);
>> -
>>         return 0;
>>  }
> 
> This doesn't work. Playback has two issues: 1) volume is very low and probably
> not adjustable and 2) sound during playback dies after a couple of seconds.
> 
> Returning these global_mbias() calls restores the good behaviour.

What is global micbias to do with rx playback? Maybe something is missing.

Which RX path are you testing?

I am testing this with Headphone and Lineout, it works for me.

> 
> Maybe let's make a widget out of it? In such case I am not sure about
> routing meaning that I not sure which paths do require mbias enable.
Not sure why RX would need mic bias?


--srini
> 
> Best regards,
> Alexey