[alsa-devel] [bug] SPDIF (digital-out) not working on NForce4/CK804

[Raymond Yau]

>
> Sorry to bump in like this, but I was advised to submit a bug-report for
the ALSA-drivers on my HTPC: no sound comes through out of my AVR when I
select the digital output through SPDIF (TOSLINK).
>
>
> The relevant parts of my HTPC are as follows:
>     * CPU: Athlon64 X2 3800+
>     * Motherboard: ASUS A8N-SLI Deluxe motherboard (BIOS 1805) NForce4
with CK804 sound (relying on a Realtek ALC850 chip)

>     * RAM: 2x 512 MB DDR-400
>     * GPU: nVidia Geforce GT240 (which carries a HDMI port and uses the
snd-
>     * Receiver: Marantz SR7500 (supporting both Dolby Digital 5.1 and DTS
decoding), connected to motherboard's SPDIF TOSLINK port (optical) + JBL
5.1 speaker-set
>     * OpenElec 4.2.0: Kernel 3.16.3, Alsa 1.0.28
>
>
> Symptoms:
> Speaker-test does not produce any sound. Command used is as follows:
>
>     speaker-test -c2 -r 48000 -D hw:0,2
>
> No sound either from other applications (such as XBMC 13.2).
>
> SPDIF worked flawlessly on the exact same hardware & connections using
Win7/XBMC.
> Sound does come through the SPDIF when I use hw:0,0 (= analog device).
>
>
> Things tried (none working):
>     * Blacklisting snd-hda-intel (= HDMI from my GPU) to make sure CK804
is the only sound chip visible.
>
>     * amixer set 'IEC958 Playback AC97-SPSA' Playback 100% unmute

http://www.realtek.com.tw/products/productsView.aspx?Langid=1&PFid=31&Level=5&Conn=4&ProdID=59

Take a look at alc850 datasheet

Simple mixer control 'IEC958 Playback AC97-SPSA',0
  Capabilities: volume volume-joined
  Playback channels: Mono
  Capture channels: Mono
  Limits: 0 - 3
  Mono: 0 [0%]

This is not volume control, it is SPDIF out Slot Assignment in ac97 link

You have to use iec958:CARD=CK804

http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=src/conf/cards/NFORCE.conf;hb=HEAD

Simple mixer control 'IEC958 Playback Source',0
  Capabilities: enum
  Items: 'PCM' 'Analog In' 'IEC958 In
  Item0: 'PCM'

>
>     * Contacted XBMC developer via IRC for investigation: concluded that
problem would be with kernel driver, advised to create this bug-report.
>
>     * Tried another distro (Ubuntu from XBMCBuntu 13.0).
>
>
> Further details which might be useful:
>     * alsa-info.sh output:http://pastebin.com/Bp2ZGfZb
>
>     * /proc/asound/card0/ac97#0-0:http://pastebin.com/Q5y1J0Ra
>
>     * /proc/asound/card0/ac97#0-0+regs:http://pastebin.com/tBbTCxZg
>
>
> Similar reports found (no working solution):
>
http://mailman.alsa-project.org/pipermail/alsa-devel/2009-September/021336.html
>
http://askubuntu.com/questions/264272/no-sound-output-msi-k8n-neo4-ck804-ac97
>
http://askubuntu.com/questions/462605/new-install-of-ubuntu-14-04-trusty-3-audio-devices-no-sound
>    https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=615225
>    http://ehc.ac/p/alsa/mailman/message/25973743/
>    http://wiki.linuxmce.org/index.php/ASUS_A8N-SLI_Deluxe
>    http://forum.xbmc.org/showthread.php?tid=156043&pid=1348176
>    http://forum.xbmc.org/showthread.php?tid=168608
>    http://ubuntuforums.org/showthread.php?t=2210288
>    http://cholla.mmto.org/computers/linux/sound/asus_a8ne.html
>    http://www.nvnews.net/vbulletin/showthread.php?t=80521
>     ...
>