5.1/7.1 multichannel audio using VoodooHDA

[Cassio]

In order to have multichannel audio in Mac OS we just have to open Applications - Utilities - Audio MIDI Setup and create an aggregate device with 3 (5.1) or 4 outputs (7.1)

The problem is that on most codecs VoodooHDA enables only one output. It happens because the codec has more than one node with the same Default Association, only Sequence changes.

To get a dump of your codec use the getDump command (get it in VoodooHDA official thread).

Example:

nid 17 0x02214030 as  3 seq  0	Headphones  Jack jack  1 loc  2 color   Green misc 0
nid 18 0x010140[color=#FF0000]1[/color]0 as  1 seq  0	  [color=#FF0000]Line-out[/color]  Jack jack  1 loc  1 color   Green misc 0
nid 19 0x511711f0 as 15 seq  0	   Speaker  None jack  7 loc 17 color   Black misc 1
nid 20 0x02a1902e as  2 seq 14	Microphone  Jack jack  1 loc  2 color	Pink misc 0
nid 21 0x01813021 as  2 seq  1	   Line-in  Jack jack  1 loc  1 color	Blue misc 0
nid 22 0x010110[color=#FF0000]1[/color]2 as  1 seq  2	  [color=#FF0000]Line-out[/color]  Jack jack  1 loc  1 color   Black misc 0
nid 23 0x01a19020 as  2 seq  0	Microphone  Jack jack  1 loc  1 color	Pink misc 0
nid 24 0x99331122 as  2 seq  2	  CD Fixed       jack  3 loc 25 color   Black misc 1
nid 27 0x0145f1a0 as 10 seq  0	 SPDIF-out  Jack jack  5 loc  1 color   Other misc 1
nid 28 0x41c5f160 as  6 seq  0	  SPDIF-in  None jack  5 loc  1 color   Other misc 1
nid 36 0x010160[color=#FF0000]1[/color]1 as  1 seq  1	  [color=#FF0000]Line-out[/color]  Jack jack  1 loc  1 color   Orange misc 0
nid 37 0x010120[color=#FF0000]1[/color]4 as  1 seq  4	  [color=#FF0000]Line-out[/color]  Jack jack  1 loc  1 color	Grey misc 0

 

PinDefault is composed of 8 hex chars

0x01011012
 |||||||+- Sequence
 ||||||+-- Default Association
 |||||+--- Misc
 ||||+---- Color
 |||+----- Connection Type
 ||+------ Default Device
 |+------- Location
 +-------- Port Connectivity

 

More info http://Olarila.com/forum/viewtopic.php?f=18&t=454

Apple doesn't use multichannel analog output, so we need to use a different Default Association for each line-out (use the first available value). Sequence is always zero.

To change these values we include NodesToPatch in VoodooHDA Info.plist file, for example:

NodesToPatch


Codec
0[b][/b]
Config
0x010110[b]70[/b][b][/b]
Node
22[b][/b]

 

In some cases it's also necessary to adjust Port Connectivity. For jacks, bits 6 and 7 must be zero, so any value greater than 1 in char 7 of PinDefault means the node is disabled (you will see "Disabling pin nid X due to None connectivity" in getDump).

This also works for inputs, so if you don't have mic or line-in in sound preferences, you can use the same method to enable the inputs.

The only case we use the same Default Association in two nodes is when we want auto-detection, for example, line-out (green rear) and headphones (green front)

nid 17 0x022140[color=#FF0000]1f[/color] as  1 seq 15	Headphones  Jack jack  1 loc  2 color   Green misc 0
nid 18 0x010140[color=#FF0000]10[/color] as  1 seq  0	  Line-out  Jack jack  1 loc  1 color   Green misc 0

The primary output (line-out or speaker) has Sequence 0 and headphones (auto-detect) has Sequence f.

If your mobo has only one line-out you can change rear mic and line-in into line-out to have 5.1 audio, for this you just have to change the Default Device byte of these nodes to zero.

Before

nid 24 0x01[b]a[/b]19830 as  3 seq  0    Microphone  Jack jack  1 loc  1 color    Pink misc 8
nid 26 0x01[b]8[/b]13050 as  5 seq  0       Line-in  Jack jack  1 loc  1 color    Blue misc 0

After

nid 24 0x01[b]0[/b]19830 as  3 seq  0      Line-out  Jack jack  1 loc  1 color    Pink misc 8
nid 26 0x01[b]0[/b]13050 as  5 seq  0      Line-out  Jack jack  1 loc  1 color    Blue misc 0