[alsa-devel] HD-audio regression after commit 34588709af61be1550b4e2bcee5c85d0ac4f34d4

[Takashi Iwai]

At Sun, 20 Jan 2013 14:54:39 -0500,
Miro Hodak wrote:
> 
> On Sat, Jan 19, 2013 at 6:11 AM, Takashi Iwai <tiwai at suse.de> wrote:
> 
> > At Sat, 19 Jan 2013 00:33:52 -0500,
> > Miro Hodak wrote:
> > >
> > > Testing latest updates in sound-unstable:
> > >
> > > commit f741c8a1f649379f8f3eb81119df2676c46075cf
> > > Merge: d821c1e 164a7ad
> > > Author: Takashi Iwai <tiwai at suse.de>
> > > Date:   Fri Jan 18 18:30:00 2013 +0100
> > >
> > > Playback and capture appear to work correctly with one possible caveats:
> > >
> > > Item labeled "Front" controls the level of sound through the speakers. I
> > > would expect that it would only control sound from front HP. This happens
> > > whether Independent HP is on and off.
> >
> > When you look at other controls, there are "Surround", "Center", and
> > "LFE", and these are mixer controls for other two line-out jacks.
> > In that sense, "Front" is corresponding to the same group, the line
> > out jack.
> >
> > You have an individual "Headphone" output.  Isn't it obvious?
> >
> >
> > Takashi
> >
> 
> Not always, most labels are one word long and can be open to different
> interpretations. In alsamixer, ordering of capture controls is the
> following:
> 
> Master  Headphon   PCM     Front   Front Mi  Surround  Center    LFE
> Side  Line Boo  S/PDIF  S/PDIF D Auto-Mut Independ <Rear Mic>
> 
> and thus "Front" is next to "Front Mi" - that should connect at the front I
> assume - rather then to other outputs at the back. Thus it is very easy to
> get confused.

I see.  Yes, the usage of the word "front" has been a problem since
long time ago, basically because it can mean two different things: the
position of the jack and the channel location.  But, this has been so,
thus it's no regression to fix urgently.


> Here are outputs as specified in my MB manual and my attempt to pair them
> to items in alsamixer (Capture only):
> 
> MB description                                   Alsa control (capture)
> BACK PORTS:
> Line In                                                  Line Boost (its
> boost only, I know)
> Front Speaker Out                             Front
> Mic In                                                   Rear Mic Boost
> Center/Subwoofer                             Center
> Rear Speaker Out                             ???
> Side Speaker Out                              Side
> 
> FRONT PORTS:
> Headphone Out                                Headphone
> Front Mic In                                        Front Mic Boost
> 
> There are two items that have not been assigned - Surround and LFE,
> presumably one of them should correspond to the "Rear Speaker Out" for
> which I could not identify ALSA control. Not being familiar with more than
> 2-channle audio, I do not know how to assign these.

"Surround" corresponds to the rear channel in ALSA term.
"LFE" is a more official name of subwoofer.


Takashi