[alsa-devel] [PATCH] Re: iec958 switch uneffective while playing ac3 stream

[Takashi Iwai]

At Fri, 6 Apr 2007 15:44:06 -0400,
Lee Revell wrote:
> 
> On 4/6/07, Dominique Dumont <domi.dumont at free.fr> wrote:
> > Takashi Iwai <tiwai at suse.de> writes:
> >
> > > OK, now it's on HG tree.
> >
> > Thanks.
> >
> > > While we're at it...  I did a quick hack to add a new mixer element to
> > > choose the SPDIF playback route, either "Analog Duplicate" or
> > > "Exclusive PCM".  (On AD codecs, it has more items for analog
> >
> > Hmm, I hope you won't think I'm nitpicking, but this term "Exclusive
> > PCM" might be misleading as AC3 or DTS streams are not PCM...
> >
> > May be "Exlusive Digital" would be better... Does any native english
> > speaker have a better suggestion ?
> 
> How about Digital Mode: { Independent | Shared }?  Similar to the
> existing controls for surround jack mode.

I don't care much about wording, so I'd like to ask you guys which
one is better.  In general, we have the following modes for SPDIF
output:

1. "Exclusive" / "Independent" mode
  You'll have a dedicated SPDIF stream, suitable for AC3/DTS output.

2. "Duplicate" / "Shared" mode
  The normal analog output is copied to SPDIF output.

3. (codec-dependent) "Analog Loopback" mode
  The analog line-in / CD / mic-in (and mixer) is loopbacked to SPDIF
  output

4. (codec-dependent) "SPDIF Loopback" mode
  The SPDIF-input is loopbacked to SPDIF output


Takashi