[alsa-devel] [PATCH 1/4] ALSA: hda - hdmi: Add ATI/AMD multi-channel audio support

Anssi Hannula anssi.hannula at iki.fi
Fri Nov 1 00:34:56 CET 2013

01.11.2013 01:25, Rafał Miłecki kirjoitti:
> 2013/10/31 Anssi Hannula <anssi.hannula at iki.fi>:
>>> But I can hear sound for rear right and rear left only :(
>>> Is there anything more I can provide to help resolve this? Do you have
>>> any idea how we can resolve this?
>> According to the below the receiver has separate PCM SADs for 2-channel
>> and multichannel playback. However, due to a radeon driver bug (see
>> "[PATCH] drm/radeon/audio: fix missing multichannel PCM SAD in some
>> cases", you were CCd) the multichannel SAD is lost and not shown below.
>> However, that is not (or at least should not be) the reason you are not
>> getting audio.
>> I suspect that the receiver does not support 192kHz multichannel audio
>> (which would be indicated in the missing multichannel PCM SAD). Does it
>> work with 48kHz or 96kHz?
>> (TODO: refuse PCM playback in such cases)
>> If it does not work with 48kHz or 96kHz either, then we have a bug to
>> solve :)
> First of all, you're right about 2 SADs for PCM.
> The weird thing is that 192kHz support... According to the EDID (SADs)
> it should be supported:
> Format: 1 (PCM)        Channels:1    Freq:0x7F (32-192)    B2:0x07 (16-24b)
> Format: 1 (PCM)        Channels:7    Freq:0x7F (32-192)    B2:0x07 (16-24b)
> Format: 2 (AC3)        Channels:7    Freq:0x07 (32-48)    B2:0x50 (640?)
> Format: 7 (DTS)        Channels:7    Freq:0x06 (44-48)    B2:0xC0 (1536?)
> Format: 10 (EAC3)    Channels:7    Freq:0x06 (44-48)    B2:0x00
> Format: 11 (DTS_HD)    Channels:7    Freq:0x7E (44-192)    B2:0x01
> Format: 12 (MLP)    Channels:7    Freq:0x1E (44-96)    B2:0x00
> So I performed more tests and:
> 1) speaker-test -D hdmi:CARD=Generic,DEV=0 -c6 -r192000 -F S16_LE
> A nice noise for rear right and rear left, silent for the rest
> 2) speaker-test -D hdmi:CARD=Generic,DEV=0 -c6 -r176400 -F S16_LE
> A nice noise for rear right and rear left, short "bump" sound for the rest
> 3) speaker-test -D hdmi:CARD=Generic,DEV=0 -c6 -r96000 -F S16_LE
> A nice noise for all speakers (the same applies to 88200, 48000, 44100, 32000)
> I don't get it. Onkyo reports support for 192kHz and it supports it,
> but only for 2 rear speakers... does it make any sense do you?

Just to check, is the display mode 720p50 or higher (as per HDMI spec
7.3.3)? Though I guess too small mode would cause something else, not

Also, does DTS-HD/TrueHD work with this receiver (interesting since
those require 8-channel 192kHz link)?

Would be interesting to check if this works in Windows I guess (or maybe
even just fglrx, though I can't think of a reason it'd make a difference).

Anssi Hannula

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