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

[Takashi Iwai]

At Thu, 4 Jun 2009 08:18:23 +0200,
Alan Alan wrote:
> 
> 2009/6/4 Takashi Iwai <tiwai at suse.de>
> 
>     At Thu, 4 Jun 2009 01:28:24 +0200,
>     Alan Alan wrote:
>     >
>     > Hello Takashi !
>     >
>     > I tried to apply the patch that removes restrictions to 16bits 48khz
>     format.
>     > Well now we have the following:
>     > 16bit 48khz                                     works
>     > 32bit 48khz                                     works
>     > 32bit 44khz, 96khz, 192khz              don't work
>     > 24bit 44khz, 48khz, 96khz, 192khz   don't work
>     > 16bit 44khz, 96khz, 192khz              don't work
>     >
>     > I only get
>     > Sample format not available for playback:
>     > Setting of hwparams failed:
>    
>     As you can find in alsa-info output, it seems that the codec supports
>     only 48kHz and 88.2kHz, strangely.  I don't know whether it's a
>     (hardware) bug or not.
> 
> The codec surely supports up to 192khz as it works on Windows.
> 
> I think this line is completely wrong as here it says:

It is not "wrong".  These are values that the codec reports, so it's
more or less correct as the h/w information.

>   rates [0xc0]: 48000 88200

Wei, is it right?  Or is anything missing here?


>     bits [0xf]: 8 16 20 24
> 
> 8, 20, 24bits are supported, but they all give an error message.

24bit here means 24bit in 4 bytes, thus it's essentially 32bit format.
24bit in 3 bytes format isn't supported on HD-audio.

> 32 bits are not supposed to be supported but it works with 48 and 88.2khz.
> 
> How can we change the software side to accept 96 or 192khz spample formats and
> 24 bits ?

As long as the codec reports so, it's no "software" problem.

> I think it is not hardware limited and we just need to change the allowed
> formats to be played.

If it's just a hardware problem that reports wrong values, you can
override the information, simply replacing the bits my patch disabled
to the right values.


Takashi

>    
>     >
>     > I enclosed to pastebin my alsainfo script output.
>     >
>     > http://pastebin.com/m77dcfb3f
>     >
>     > Thanks for the help !
>     >
>     > 2009/6/3 Takashi Iwai <tiwai at suse.de>
>     >
>     >     At Wed, 3 Jun 2009 11:34:00 +0200,
>     >     Alan Alan wrote:
>     >     >
>     >     > Hello Takashi !
>     >     >
>     >     > What should this patch do ?
>     >
>     >     The patch removes the restriction patch_nvhdmi.c sets.  Instead,
>     >     the driver tries to detect the supported format, rate, etc from the
>     >     codec widget information.
>     >
>     >     > Is it a cure for the 96, 192khz or 24bit sample playback problem ?
>     >
>     >     Possibly.
>     >
>     >     > If so, will it resample or natievly pass the stream to the
>     amplifier ?
>     >
>     >     It just enables the native support, possibly.
>     >
>     >     And, don't forget to give back the alsa-info.sh output (run with
>     >     --no-upload option).
>     >
>     >     Takashi
>     >
>     >     >
>     >     > Thank you
>     >     >
>     >     > Alan
>     >     >
>     >     > 2009/6/3 Takashi Iwai <tiwai at suse.de>
>     >     >
>     >     >     At Wed, 3 Jun 2009 10:00:24 +0200,
>     >     >     Alan Alan wrote:
>     >     >     >
>     >     >     > Hello Wei !
>     >     >     >
>     >     >     > Thanks for replying.
>     >     >     > I tested it with speaker-test and xbmc babylon. Both had
>     problems
>     >     with
>     >     >     > channel mapping.
>     >     >     > I used this command:
>     >     >     >
>     >     >     > speaker-test -Dhdmi -c6
>     >     >     > or
>     >     >     > speaker-test -Dhdmi -c8
>     >     >     >
>     >     >     > alternatively you could try
>     >     >     >
>     >     >     > speaker-test -Dhw:0,3 -c6
>     >     >     >
>     >     >     >
>     >     >     > I had to rund Xorg first and have the command from an xterm,
>     >     becasue
>     >     >     from a
>     >     >     > normal terminal it would not work.
>     >     >     > I think that is normal as a limitation of hdmi.
>     >     >     >
>     >     >     > What about the support for 24bits 192khz sound ?
>     >     >     >
>     >     >     > speaker-test -Dhdmi -c6  -r192000 does not work.
>     >     >
>     >     >     How about the patch below?
>     >     >
>     >     >     Also, could you give alsa-info.sh output?
>     >     >
>     >     >     Takashi
>     >     >
>     >     >     ---
>     >     >     diff --git a/sound/pci/hda/patch_nvhdmi.c b/sound/pci/hda/
>     >     patch_nvhdmi.c
>     >     >     index f5792e2..48443de 100644
>     >     >     --- a/sound/pci/hda/patch_nvhdmi.c
>     >     >     +++ b/sound/pci/hda/patch_nvhdmi.c
>     >     >     @@ -258,9 +258,11 @@ static struct hda_pcm_stream
>     >     >     nvhdmi_pcm_digital_playback_8ch = {
>     >     >            .channels_min = 2,
>     >     >            .channels_max = 8,
>     >     >            .nid = Nv_Master_Convert_nid,
>     >     >     +#if 0
>     >     >            .rates = SNDRV_PCM_RATE_48000,
>     >     >            .maxbps = 16,
>     >     >            .formats = SNDRV_PCM_FMTBIT_S16_LE,
>     >     >     +#endif
>     >     >            .ops = {
>     >     >                    .open = nvhdmi_dig_playback_pcm_open,
>     >     >                    .close = nvhdmi_dig_playback_pcm_close_8ch,
>     >     >     @@ -273,9 +275,11 @@ static struct hda_pcm_stream
>     >     >     nvhdmi_pcm_digital_playback_2ch = {
>     >     >            .channels_min = 2,
>     >     >            .channels_max = 2,
>     >     >            .nid = Nv_Master_Convert_nid,
>     >     >     +#if 0
>     >     >            .rates = SNDRV_PCM_RATE_48000,
>     >     >            .maxbps = 16,
>     >     >            .formats = SNDRV_PCM_FMTBIT_S16_LE,
>     >     >     +#endif
>     >     >            .ops = {
>     >     >                    .open = nvhdmi_dig_playback_pcm_open,
>     >     >                    .close = nvhdmi_dig_playback_pcm_close_2ch,
>     >     >
>     >     >
>     >
>     >
> 
>