[alsa-devel] [PATCH 0/30] ALSA: HDA VIA: patch series

[Takashi Iwai]

At Sun, 11 Oct 2009 13:51:28 -0600,
Robert Hancock wrote:
> 
> On 10/11/2009 01:27 PM, Takashi Iwai wrote:
> > At Sun, 11 Oct 2009 10:56:48 -0600,
> > Robert Hancock wrote:
> >>
> >> On Sun, Oct 11, 2009 at 10:18 AM, Takashi Iwai<tiwai at suse.de>  wrote:
> >>> At Sat, 10 Oct 2009 19:07:09 +0800,
> >>> Logan Li wrote:
> >>>>
> >>>> Following patch series mainly includes:
> >>>>   - support VT1718S, VT2002P, VT1812S, VT1716S, ...
> >>>>   - support smart 5.1
> >>>>   - add jack detection for VT1708
> >>>>   - power saving functions
> >>>
> >>> Thanks for the patches.  They are all well formatted now.
> >>>
> >>> I applied your patches except for 17,
> >>>         ALSA: HDA VIA: Add 2nd S/PDIF out for VT1708S and VT1702
> >>> as Robert reported a regression.
> >>>
> >>> This is likely because of the behavior change by this patch.  Now
> >>> the second SPDIF has to be specified manually with the explicit
> >>> substream number.  This itself is fine, but I see the problem with
> >>> pulseaudio, for example.  There is no good way to specify this substream
> >>> automatically for PA with some symbols like "spdif" or "hdmi".
> >>>
> >>> This is basically a problem of the current ALSA core and HD-audio core
> >>> implementation.  So, we should solve all together.
> >>
> >> Actually, the latest posted version didn't have the mixer problem I
> >> had before (I haven't looked in detail at what was different). But I
> >> agree using a different substream for a different output isn't ideal
> >> since there's no way for software to detect that this is the case. Can
> >> it be a separate PCM like hw:0,2 or something?
> >
> > It would work like hw:0,1,1.  But, this is exactly what I mentioned in
> > the above.  The secondary SPDIF isn't specified as an intuitively
> > selectable PCM device.
> 
> Well, if it was its own subdevice like hw:0,2 it would have some hope of 
> being detected by HAL, PulseAudio, etc. If it's just a substream then I 
> don't think that software can actually tell it's a separate output and 
> not just a HW mixing-type stream, etc.

Right, that's the missing information.

> >> Hopefully VIA will also look into the SPDIF no-output problem I have
> >> with VT1828S..
> >
> > What is the problem, specifically?
> 
> With the latest patch I do get the optical output lighting up and the 
> receiver detects a PCM signal, but it seems to be just silence coming 
> through. (In previous iterations the SPDIF digital converter wasn't 
> being enabled automatically so it didn't get even that far.)

You can fiddle with hda-verb to issue digital-converter verbs.
Possibly you need to flip the digital-enable bit to send the values...


thanks,

Takashi