On 05/13/2014 12:13 AM, Joachim Eastwood wrote:
On 12 May 2014 11:12, Jyri Sarha <jsarha@xxxxxx> wrote:
...
hey, this worked straight away :) But there seems to be something wrong with the channel mapping. For stereo (speaker-test -c 2) the mapping is correct. But for -c 4 and -c 8 it gets weird: speaker-test -c 4 -s X # where X is 1-4 1: Front Left is Rear Left 2: Front Right is Rear Right 3: Rear Right is Front Right 4: Rear Left is Front Left speaker-test -c 8 -s X # where X is 1-8 1: Front Left is Rear Left 2: Center is Rear Left 3: Front Right is Rear Right 4: Side Right is Front Right 5: Rear Right is silent 6: Rear Left is Center 7: Side Left is Front Left 8: LFE - Rear Right I think you need to check what channel order ALSA expects. I believe speaker-test does the right thing on my HTPC normally connected to my receiver.
I checked the implementation and there was indeed something weird there, but the implementation can not explain the FL and FR channels jumping around. FL and FL should always be the first two channels in all configurations and the implementation does not touch them.
The implementation uses 8ch HDMI setup for anything above 2ch with "Audio InfoFrame Data Byte 4" set to 0x13. According to CEA-861 specs this means following channel order: FL, FR, LFE, FC, RL, RR, RLC, RRC
This is a closest match to ALSA 8ch mapping (according to sound/core/pcm_lib.c) which is: FL, FR, FC, LFE, RL, RR, SL, SR
Current implementation has FLE and FC channels correctly swapped, but it shifts them to last two channels and RL, RR, SL, SR are shifted down to fill the place. This is all wrong and I'll try to come up with a fix for that. Unfortunately I can not test anything beyond 2 ch myself so I would need someone to volunteer to test my patch.
Best regards, Jyri -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
