[alsa-devel] [RFC PATCH 1/2] ALSA: hda - Fix "PCM" name being used on one DAC when there are two DACs

Takashi Iwai tiwai at suse.de
Mon Oct 20 07:54:01 CEST 2014


At Mon, 20 Oct 2014 09:10:05 +0800,
Raymond Yau wrote:
> 
> > >
> > > > >
> > > > > >> >
> > > > > >> > In the scenario where there is one "Line Out", one "Speaker"
> and
> > > one
> > > > > >> > "Headphone", and there are only two DACs, two outputs will
> share a
> > > DAC.
> > > > > >> > Currently any mixer on such a DAC will get the "PCM" name,
> which is
> > > > > >> > misleading. Instead use "Headphone+LO" or "Speaker+LO" to
> better
> > > > > >> > specify what the volume actually controls.
> > > > > >>
> > > > > >> Are there any examples ?
> > > > > >>
> > > > > >
> > > > > > I used "hda-emu
> > > > > codecs/canonical/alc3226-dell-precision-m2800-ccert-201404-14986 -i
> 1"
> > > when
> > > > > developing the patches.
> > > > > >
> > > > > > I don't have any hardware available myself that exposes this
> behavior,
> > > > > but I can maybe fake one with hdajackretask, if that counts...
> > > > > >
> > > > >
> > > > > How about adding these names to slaves of virtual master
> volume/switch ?
> > > > >
> > > > > hdajackretask won't help if the topology of the codecs are
> different
> > > > >
> > > > > Seem the badness still prevent the driver to support surround 5.1
> with
> > > > > three rear panel jacks, internal speaker and front panel headphone
> for
> > > > > Thinkcenter A58 using alc662
> > > > >
> > > > >
> > >
> https://www.mail-archive.com/alsa-user@lists.sourceforge.net/msg29203.html
> > > > >
> > > > > Why 3stack desktops with 6 channels codecs not using
> "Headphone+LO"  or
> > > > > "Speaker+LO" ?
> > > >
> > > > The problem is just the lack of DACs, so it cannot cover all three
> > > > outputs, no matter how the pins are chosen.  That is, it's no 6
> > > > channels at all but 4 channels at most.
> > > >
> > > >
> > >
> > >http://shop.lenovo.com/us/en/desktops/thinkcentre/a-series/a58/
> > >
> > > The technical specification of a58
> > >
> > > 2 pin internal speaker connector
> > > Alc662 5.1
> > >
> > >https://bbs.archlinux.org/viewtopic.php?id=156433
> > >
> > > Seem windows support surround 5.1
> >
> > ALC662 has three DACs, so it's a different problem, if any.
> > ALC269 and its variants have only two DACs.
> >
> >
> 
> These two patches not only affect those four channels hda codecs notebook
> with dock station or desktop with internal speaker, it also affect some
> codecs in hda-emu/codecs
> 
> 1) two channels hda codec such as stac9200 (e.g Dell precision 490
> workstation)
> 2) 8 channels codecs such as stac9228, cmi9880 (e.g. lg-lw60 and dell xps)
> 
> The proposed patches still not able to handle the case when line out ,
> headphone and speaker share the same volume control

We need to test through all codecs and configs, but I thought the case
1 won't hit.  This should still result in "PCM" volume.

Which problem does the latter case have?  Do they have also shared
volumes although they have more number of DACs than pins?

> Refer to hardware mainteance manual of a58, there is only one internal
> speaker , it is most likely a mono speaker if it use a two pin internal
> speaker connector
> 
> http://www.desktopreview.com/default.asp?newsID=760&Review+Lenovo+ThinkCentre+A58
> 
> Here you can see the built-in speaker in the lower right
> 
> It is unlikely for  stereo speaker to use two pin connector

Raymond, this is utterly irrelevant with the volume control
assignment.  Just open up a different discussion thread.


Takashi


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