[alsa-devel] Usb driver correction

LCID Fire lcid-fire at gmx.net
Sun Jan 27 18:14:16 CET 2008

I hope you guys can help me with 3 problems I have.
I have a usb device which has 3 streams - which all work fine (that's
not the problem yet ;)).
Aside from this there is also a mixer created. Alsa cannot retrieve any
information from the mixer - not the minimum, nor the maximum or current
value. Basicly alsa leaves the mixer in a state where it cannot be used
- which leads to a question why not omnit the mixer?
What I am ending up with are these 2 volumes:
[4] FU [PCM Capture Volume] ch = 1, val = 0/1/1
[9] FU [PCM Capture Volume] ch = 1, val = 0/1/1

What would I have to do to disable these?
Is it enough to define a usbmix_name_map in usbmixer_maps.c with {4,
NULL} and {9, NULL}?

Also, the usb device has a switch - from line input to phono input. I
know what control message I have to send to change the switch - but
where has such an additional switch to be implemented?
Is it similar to snd_audigy2nx_led_get in usbmixer.c?

Would be great if someone could explain these mysteries to me ;)

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