[alsa-devel] Verb table for group section

[Takashi Iwai]

On Tue, 12 Dec 2017 10:49:12 +0100,
Kailang wrote:
> 
>  
> 
> > -----Original Message-----
> > From: Takashi Iwai [mailto:tiwai at suse.de] 
> > Sent: Tuesday, December 12, 2017 5:10 PM
> > To: Kailang
> > Cc: (alsa-devel at alsa-project.org)
> > Subject: Re: Verb table for group section
> > 
> > On Tue, 12 Dec 2017 09:30:18 +0100,
> > Kailang wrote:
> > > 
> > > Hi Takashi,
> > >  
> > > Attach file was ALC274 in our ENG test machine.
> > >  
> > > 0x16 0x90170110   => speaker
> > > 0x19 0x01a1913c   => headset mic
> > > 0x1a 0x01a1913d   => headphone MIC
> > > 0x1b 0x04011020  => Line out
> > > 0x21 0x0421102F  => Headphone
> > >  
> > > How could i set verb for group and sequence that Line out 
> > and Headphone will use DAC 0x03?
> > 
> > What is the exact restriction?  0x1b and 0x21 must use 0x03 
> > while 0x16 to 0x02?
> 
> Because the EQ support on DAC 0x02. If speaker muted, EQ will disable.
> 
> > 
> > If yes, try to define spec->gen.preferred_dacs[].  It's a 
> > list of paired NIDs to define the preferred DAC for each pin. 
> >  For example,
> > 
> > 	{ 0x1b, 0x03, 0x21, 0x03, 0x16, 0x02, 0 }
> > 
> > (don't forget the zero-termination).
> 
> static void alc274_dell_fixup_dac_bind(struct hda_codec *codec,
> 					    const struct hda_fixup *fix,
> 					    int action)
> {
> 	struct sigmatel_spec *spec = codec->spec;
> 	static hda_nid_t preferred_pairs[] = {
> 		0x21, 0x03, 0x1b, 0x03, 0x16, 0x02,
> 		0
> 	};
> 
> 	if (action != HDA_FIXUP_ACT_PRE_PROBE)
> 		return;
> 
> 	spec->gen.preferred_dacs = preferred_pairs;
> }
> 
> I use upper. It was assigned to 0x03 for 0x1b.
> But could I set it to default for ALC274?
> Speaker always use DAC 0x02. Other outs use DAC 0x03.

If it's a restriction of the codec, it should be OK to assign that
table always, yes.  But please put the proper comment what it does and
why it's necessary.


Takashi