[alsa-devel] Verifying mixer dB data/Invalid dB data from USB cards, especially Aureon 5.1 MkII

Raymond Yau superquad.vortex2 at gmail.com
Sun Feb 21 05:01:20 CET 2010

2010/2/19 Lennart Poettering <mznyfn at 0pointer.de>

> > Is HDA_SUBDEV_NID_FLAG or any API for the application to find the correct
> > mixer control for these kind of capturing subdevices  ? ( simple mixer
> api
> > is not able to know the subdevice number )
> There is currently no API at all to figure out the relation between PCM
> devices and mixer controls in ALSA. PA hences bases this all on
> assumptions and expectes in this acse that the first mixer control is
> also the first PCM device, if you understand what I mean by that.
> Lennart
No, there is API which allow PA to find out the correct mixer control

However Simple Mixer API cannot know the subdevice number , you have to use
control API ( the lower level API used by Simple Mixer API )

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