On Sun, Mar 17, 2024 at 07:27:14PM +0300, Jan Dakinevich wrote:

Both mic bias and ADC's input mode depends on schematics and should be
configurable. What is the better way to give access to these parameters?
Device tree?

Yes.

quoted

quoted

+	SOC_SINGLE("ADC Mic Bias Switch", LINEIN_CFG, MICBIAS_EN, 1, 0),
+	SOC_ENUM("ADC Mic Bias Level", a1_adc_mic_bias_level),

quoted

Why would micbias be user controlled rather than a DAPM widget as
normal?

Yes, I could use SND_SOC_DAPM_SUPPLY, but it supports only raw values,
and doesn't supports enums. Here, I want to use enum to restrict
possible values, because only these values mentioned in the
documentation that I have.

A supply is an on/off switch not an enum.  Users should not be selecting
values at all.