I have a BB white and one BB audio cape rev B1. kernel version 3.8.13 and debian rootfs.
I’m able to use the BB audio cape with this setup for audio output nicely but as the audio input is line in, I can’t use the mic in directly.
So, using the mic input, my hardware person has made changes to the audio cape, and he asked me to make mic bias as 2.5V.
For, making the mic bias 2.5, I got this link and a patch there:
Then I tried to use the mic to capture the input audio (using arecord) in synchronization with alsamixer I was trying to vary various parameters in the alsamixer for line2L, line2R, Mic3L etc but
could not get it working.
Then I found this, saying some changes to be done in device tree overlay for audio cape:
After this change I tried to capture the audio in a similar way playing around with alsamixer.
But nothing seems to be helping.
If anyone has successfully used the mic with audio cape, please help me out.