[LAU] Tearing my hair out with HDMI on recent Ubuntu/KXStudio

[james]

This is with:

james at audio:~$ uname -a
Linux audio 4.2.0-22-lowlatency #27-Ubuntu SMP PREEMPT Fri Dec 18 
00:06:48 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

This was Ubuntu Studio 15.10, with pulse removed and KXStudio packages 
added.


I have an AMD APU, and its connected to a HDMI processor (actually an 
Audiolab 8200AP).

james at audio:~$ lspci | grep -i audio
00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] BeaverCreek 
HDMI Audio [Radeon HD 6500D and 6400G-6600G series]
00:14.2 Audio device: Advanced Micro Devices, Inc. [AMD] FCH Azalia 
Controller (rev 01)
05:04.0 Multimedia audio controller: C-Media Electronics Inc CMI8788 
[Oxygen HD Audio]

So, we have the audio device.  But ALSA does not seem to see it.

alsamixer shows:

Card: HD-Audio Generic F1:  Help               │
│ Chip: ATI R6xx HDMI F2:  System information │
│ View: F3:[Playback] F4: Capture  F5: All F6:  Select sound card  │
│ Item: S/PDIF

ie just a runt SPDIF, no PCMs.


I think I've turned radeon audio on appropriately:

james at audio:/etc/modprobe.d$ pwd
/etc/modprobe.d
james at audio:/etc/modprobe.d$ cat radeon.conf
options radeon audio=1


In dmesg I see this:

[   16.142396] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD
[   16.442623] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD
[   16.742857] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD
[   17.043068] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD
[   17.343309] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD
[   17.643529] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD
[   17.943756] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD
[   18.243984] snd_hda_codec_hdmi hdaudioC1D0: HDMI ATI/AMD: no speaker 
allocation for ELD

I have rebooted, and restarted the Audiolab since I plugged in the HDMI 
cable.


And the ELD info seems sane:

james at audio:/proc$ cat ./asound/card1/eld#0.0
monitor_present         1
eld_valid               1
monitor_name
connection_type         HDMI
eld_version             [0x2] CEA-861D or below
edid_version            [0x0] no CEA EDID Timing Extension block present
manufacture_id          0x0
product_id              0x0
port_id                 0x0
support_hdcp            0
support_ai              0
audio_sync_delay        0
speakers                [0x4f] FL/FR LFE FC RL/RR RLC/RRC
sad_count               1
sad0_coding_type        [0x1] LPCM
sad0_channels           8
sad0_rates              [0x6e0] 32000 44100 48000 88200 96000
sad0_bits               [0xe0000] 16 20 24
james at audio:/proc$


Any idea how to tell what's going on - ?

The slight weirdness is that the system is connected to the Audiolab 
over HDMI, but I don't have an HDMI monitor - and in fact I access the 
system via putty or XRDP.