[alsa-devel] [PATCH 6/6] ASoC: Tegra: Harmony: Support both int and ext mics

Mark Brown broonie at opensource.wolfsonmicro.com
Tue Feb 8 21:58:48 CET 2011

On Tue, Feb 08, 2011 at 12:34:09PM -0800, Stephen Warren wrote:

> Maybe I should just not implement mic detection for Harmony due to these
> issues? In which case, I'd just let mic bias be enabled whenever capture
> was active, just like the speaker enable GPIO.

It certainly seems way more trouble than it's worth: as soon as the
on board mic is used the jack detection will get confused as it'll see
it.  Of course, the internal mic is actually plugged in to a header on
the main board so it may be absent too (I believe a lot of units were
shipped without a case...) which means detecting the internal mic might
actually be useful :)

> Either way, I suppose I should add two explicit mic widgets, each directly
> driving the appropriate GPIO, so that the user can select which mic(s)
> actually get used for capture.

> Does that sound reasonable?

I think that's the best approach.  If someone wants to do mic detection
they can always add it later.

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