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

[Raymond Yau]

>>
>>
>>  > >
>>  > > >> >
>>  > > >> > 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
>
>
> Raymond, there can certainly be cases which this patch does not cover -
after all, it's mostly a band aid given the lack of topology information -
but do you see cases where this patch actually causes a *regression*? If
so, could you point me to alsa-info for the machine where this patch causes
a regression?
>

www.realtek.com.tw/products/productsView.aspx?Langid=1&PNid=24&PFid=27&Level=5&Conn=4

I expect those desktop with 2+2 HD Audio codec support independent headphone

This mean the driver should not create "Lineout+HP" Playback volume

Line out and headphone cannot share same DAC