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

[Raymond Yau]

2010/2/24 Lennart Poettering <mznyfn at 0pointer.de>

> On Tue, 23.02.10 12:47, Raymond Yau (superquad.vortex2 at gmail.com) wrote:
>
> > > > The most common onboard audio is HDA so this is not any exceptional
> cases
> > > >
> > > > Those HDA multi streaming  feature are most users wanted in desktop
> > > > enviornment, are pulseaudio really designed for deskop or just only
> for
> > > > notebook and mobile ?
> > > >
> > > > The front panel green/pink jack can be used by one application while
> the
> > > > rear panel audio jacks can be used to another application for
> surround or
> > > > mic for karaoke
> > >
> > > I am not entirely convinced that this is really a common case.
>
> Uh, I wanted to say "use case" here...
>
> > Do any PA developer has a desktop computer  with HDA audio ?
>
> I certainly do. But the fact that this is not the most common use case
> and the ALSA API is not really up to the task yet to query the full
> routing table I am not sure supporting parallel and independant
> streaming support for heapdphones and speakers should be a priority for PA.
>
> > if ( snd_pcm_info_get_subdevices_count(pcm_info) > 1 ) && (
> > snd_pcm_info_get_subdevices_count(pcm_info) < 8 ))
> >
> > snd_mixer_selem_id_set_index(sid, snd_pcm_info_get_subdevice(pcm_info));
>
> Are you suggesting that on all drivers the the index part of a
> snd_mixer_selem_id_t directly relates to the subdevice id of a PCM
> stream on the same card? Is that true? Jaroslav, Clemens, Takashi, can
> you say something about that?
>
> (tbh I find that very unlikely, given that the device index would not be
> encoded then)
>
> Lennart
>

This is only true for those Capture controls for HDA since only HDA support
multi streaming

The reason of using ( snd_pcm_info_get_subdevices_
count(pcm_info) < 8 ) is au88x0 have at least 8 capture subdevices which
capture from one source from AC97 codec