[alsa-devel] Surround speaker connection on Acer 8951G

[Takashi Iwai]

On Mon, 19 Aug 2019 21:57:14 +0200,
Sergey 'Jin' Bostandzhyan wrote:
> 
> Hi Takashi,
> 
> On Sat, Jul 20, 2019 at 06:54:35PM +0200, Sergey 'Jin' Bostandzhyan wrote:
> > On Fri, Jul 19, 2019 at 04:44:52PM +0200, Takashi Iwai wrote:
> > > It might be some other external stuff like an external amp that is
> > > missing.  Often it's managed via GPIO or EAPD (that is controlled by
> > > HD-audio itself), but sometimes via a vendor-specific verb, or even
> > > over a completely different i2c...
> > > 
> > > In the case of vendor verbs, you can take a look at other quirks for
> > > similar models that touches lots of COEF stuff.
> > 
> > thanks for the pointers, does not sound simple, let's see if I get anywhere,
> > I will for sure try.
> 
> I am going at a slow pace, but I did not give up and I'd be happy if you or
> anyone else from the list would find the time to answer some questions from 
> time to time.
> 
> Right now I am mostly studying patch_realtek.c, as a first step I want to
> make sure that at least my known pins get set up by the driver without
> having to go via hdajackretask.
> 
> I got my build set up, I also dug up hda-decode-pincfg from the hda-emu
> sources and made it compile (very useful if one wants to understand and
> compare the pin configurations in patch_realtek.c), so now I am trying
> things out every other evening.
> 
> One part that is not quite clear to me: what the heck is ALC669X?

It's just a name string :)  Realtek seems to give a different chip
name for the certain variant for Dell or whatever big vendors.
AFAIK, basically it's the very same chip as ALC670, which is almost
compatible with ALC662 variant.

> Could someone please explain the meaning of alc_codec_rename_pci_table ?
> 
> Entry for my vendor id looks like this:
>     { 0x10ec0670, 0x1025, 0, "ALC669X" },
> 
> If I search for that vendor id further in the code, I see that it gets
> patched as ALC662?
> 
>     HDA_CODEC_ENTRY(0x10ec0670, "ALC670", patch_alc662),
> 
> At the same time the documentation in models.rst lists those numbers
> together:
> 
> ALC66x/67x/892
> 
> I already looked at the hda-audio specification from Intel to get a general
> understanding, but I was also pulling some Realtek specs which do describe
> implemented verbs and things like that (my hope was to see something
> vendor related which could hint me how to enable the subwoofer).
> 
> I was not able to find any 669 Realtek datasheets, I did however find
> the ones for ALC665 and ALC892. How specific is all of this, i.e. should I
> keep looking for the exact one or am I on the wrong path here?

The datasheet of ALC662 and similar chips should be available.
In general, there is no big difference among Realtek chips; one has
more I/O pins available, while one has less.

The vendor-specific stuff like COEF isn't found in the datasheet in
details, unfortunately.  Also, the GPIO pin connection isn't covered
by the codec datasheet, as it's rather device-specific, of course.


HTH,

Takashi