Re: [alsa-devel] [PATCH v2 10/19] ASoC: tlv320aic31xx: Add MICBIAS off setting

On Wed, Nov 29, 2017 at 03:32:51PM -0600, Andrew F. Davis wrote:

Leaving microphone bias off is a valid setting and even used in the DT binding document example. Add this setting here and document the same.

• ai31xx-micbias-vg - MicBias Voltage setting

•    0 or MICBIAS_OFF - MICBIAS output is powered off
     1 or MICBIAS_2_0V - MICBIAS output is powered to 2.0V
     2 or MICBIAS_2_5V - MICBIAS output is powered to 2.5V
     3 or MICBIAS_AVDD - MICBIAS output is connected to AVDD
  

This doesn't make much sense. If we enable the microphone with a voltage of 0V that's not going to work terribly well - I'd expect this property to control the voltage set when it's enabled, not if it's enabled.