[PATCH 4/4] ASoC: wm8904: add DMIC support

[Pierluigi Passaro]

> > > > +static const char *cin_text[] = {
> > > > +     "ADC", "DMIC"
> > > > +};

> > > > +static SOC_ENUM_SINGLE_DECL(cin_enum,
> > > > +                         WM8904_DIGITAL_MICROPHONE_0, 12, cin_text);

> > > Why would this be runtime selectable?  I'd expect the decision to use
> > > an analogue or digital microphone to be made in the hardware design.

> > I agree that dedicated HW is required, but currently SW side there's no support at all.
> > This patch is aiming to provide a way to enable DMIC on boards using it.
> > Is this supposed to be managed in a different way ?

> Via firmware description.

Can you please provide any reference approach in the kernel code ?