[alsa-devel] [PATCH] ASoC: tegra: Add DAPM widgets/routes for Harmony

[Mark Brown]

On Thu, Jan 13, 2011 at 03:22:08PM -0700, Stephen Warren wrote:

> Question: Harmony has a mono mic attached to the left input channel.
> However, the I2S controller only supports stereo. Is it possible to
> duplicate the mic input to both channels in ALSA? I know the WM8903
> can do it via the WM8903_AUDIO_INTERFACE_0 register, but I'm not
> sure how to request that in ALSA-speak. It looks like this same setup
> applies to many other platforms, but I couldn't see how the issue was
> solved, if at all.

It needs implementing it in the CODEC driver, it's not currently
supported as the feature is very rarely used.  I'll add it to the list
to look at, like I say I'm holding off until the merge window closes so
that the clock changes (and hopefully SD card support) get a chance to
merge into the tree and allow things to work out of the box as far as
possible.