[alsa-devel] ALSA patch Nvidia 8 channel hdmi audio

[Takashi Iwai]

At Sun, 7 Jun 2009 23:43:04 +0200,
Alan Alan wrote:
> 
> Hi Wei !
> 
> I made the tests changig the values in the sound/pci/hda/patch_nvhdmi.c file
> manually.
> To summarize the results i have perfect sound up to 192khz/32bits(S32_LE
> format). But only one configuration at a time.
> 
> How can we set multiple formats here, or let the system pass all formats to
> the av receiver ?
> 
> Here are the detailed results i tested.
> 
> In the source code
>         .rates = SNDRV_PCM_RATE_A
>         .maxbps = B,
>         .formats = SNDRV_PCM_FMTBIT_SC_LE,

Change like

	.rates = SNDRV_PCM_RATE_A | SNDRV_PCM_RATE_B | ...,
	.maxbps = 24,
	.formats = SNDRV_PCM_FMTBIT_A | SNDRV_PCM_FMTBIT_B | ...,

> 1. A=192000, B=24, C=16,      perfect sound, with speaker-test -Dhdmi -c6
> -r192000 -FS16_LE, no other setting working
> 2. A= 192000, B=24, C=32,     perfect sound, with speaker-test -Dhdmi -c6
> -r192000 -FS32_LE, no other setting working
> 3. A= 96000, B=24, C=32,       perfect sound, with speaker-test -Dhdmi -c6 
> -r96000 -FS32_LE, no other setting working
> 4. A=192000, B=24, C=24,      strange high pitched sound from all speakers,
> with speaker-test -Dhdmi -c6 -r192000 -FS24_LE, no other settings working
> 5. A=  96000, B=24, C=24,      strange high pitched sound from all speakers,
> with speaker-test -Dhdmi -c6 -r96000 -FS24_LE, no other settings working

S24_LE is no format for HD-audio.  It's 24bit packed in lower 3 bytes
of 4 byte frame.  For 24bit format, use S32_LE.


Takashi