[alsa-devel] [PATCH] STAC92xx : add support for missing features

Maxim Levitsky maximlevitsky at gmail.com
Tue Aug 28 03:54:29 CEST 2007


As promised, those are patches that extend patch_sigmatel.c driver to add 
missing functionality

They all are runtime tested with my STAC9227, and datasheet tested with others
Note that I did my best to ensure that even if a codec doesn't support a 
feature (and I don't know sbout that), maximum impact will be a new, 
non-working mixer control

STAC927x are almost exactly the same as STAC922x, but have DAC4

1) Center/LFE swap :
It can be sometimes useful to swap those channels, since they are on same 

I add that control only in case Center/LFE DAC is there, and supports L/R 
swap, it should be very safe.

2) Analog loopback:
Added for 922x, 927x, and for 9204/5 which has a different verb, that offers 
same analog loopback

3) Volume Knob:
Added for 9204/5, 9220/1/3, 922x 92-7x
I made it a master volume

4) Fixed support for codecs that have 2 or 3 ADC:
I added separate mixer controls for all 2/3 ADCs, and made PCM capture device 
sub-streams count to depend on actual number of ADCs

I am looking for your comments,
	Best regards,
		Maxim Levitsky

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