[alsa-devel] No sound after suspend-to-ram

[Takashi Iwai]

On Sat, 24 Oct 2015 00:01:00 +0200,
George Gugulea wrote:
> 
> Sure thing,
> 
> Kailang, yes, there is a side headphones jack and it does work OK
> after PM suspend-to-ram
> 
> I did `echo 1 > /sys/modules/snd_hda_codec/parameters/dump_coef ` and
> I attached the output but you are probably interested in this:
> 
> Node 0x20 [Vendor Defined Widget] wcaps 0xf00040: Mono
> .....
> 447c447
> <     Coeff 0x1f: 0x00c0
> ---
> >     Coeff 0x1f: 0x0000
> 464c464
> <     Coeff 0x30: 0x00b1
> ---
> >     Coeff 0x30: 0x0090
> 
> And after I reset the two processing caps, the sound is back again.
> 
> hda-verb /dev/snd/hwC0D0 0x20 SET_COEF_INDEX 0x1f
> hda-verb /dev/snd/hwC0D0 0x20 SET_PROC_COEF 0x00c0
> hda-verb /dev/snd/hwC0D0 0x20 SET_COEF_INDEX 0x30
> hda-verb /dev/snd/hwC0D0 0x20 SET_PROC_COEF 0x00b1
> 
> I'm not sure that this are the correct parameters of hda-verb (because
> I lack the knowledge of alsa development) but based on the result it
> seems to be correct

Yes, the command sequences are correct (sorry I didn't write it in
details).  Mostly only some of these bits are mandatory, but only
Realtek knows this secret...


Takashi