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.