We are using the ADSP BF527 based TLL6527M platform. The uClinux distro is 2011R1-RC3, built with toolchain 2011R1-RC4.
When we boot uClinux on our platform we find that no capture source is set :
Firing 'amixer' gives :
Simple mixer control 'Capture',0
Capabilities: cvolume cswitch penum
Capture channels: Front Left - Front Right
Limits: Capture 0 - 45
Front Left: Capture 23 [51%] [0.00dB] [off]
Front Right: Capture 23 [51%] [0.00dB] [off]
Now to enable capture from say Mic we have to do the follwoing :
amixer cset name='Capture Switch' on
arecord -d 2 | aplay -d 2
amixer sset 'Input Mux' 'Mic'
Note that we had to do a dummy capture - playback before setting Mic.
If this is not done, then the device capture from the given source (Mic in this case) takes a long time to be set, with 'arecord' capturing 'silence' in that duration.
This was not the case in 2010R1-RC4, where the Capture was on by default for Line In, and arecord used to work immediately after boot.
Are there any settings which need to be done during distro compilation?