Query about SNDRV_PCM_FORMAT_GSM

Query about SNDRV_PCM_FORMAT_GSM

[Patrick Lai]

Hi,

I see SNDRV_PCM_FORMAT_GSM is defined in asound.h. However, I do not
find any reference to this macro except pcm_misc.c. I am curious how
bps info(i.e 4.75 kbit/s) is passed down to the ALSA driver. Any
pointers?

Thanks
Patrick

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Re: Query about SNDRV_PCM_FORMAT_GSM

[Takashi Iwai]

At Wed, 22 Jun 2011 00:39:27 -0700,
Patrick Lai wrote:
> 
> Hi,
> 
> I see SNDRV_PCM_FORMAT_GSM is defined in asound.h. However, I do not
> find any reference to this macro except pcm_misc.c. I am curious how
> bps info(i.e 4.75 kbit/s) is passed down to the ALSA driver. Any
> pointers?

This is a vapor format until now, just reserved for the future
implementation :)


Takashi

Re: Query about SNDRV_PCM_FORMAT_GSM

[Mark Brown]

On Wed, Jun 22, 2011 at 11:54:56AM +0200, Takashi Iwai wrote:
> Patrick Lai wrote:

> > I see SNDRV_PCM_FORMAT_GSM is defined in asound.h. However, I do not
> > find any reference to this macro except pcm_misc.c. I am curious how
> > bps info(i.e 4.75 kbit/s) is passed down to the ALSA driver. Any
> > pointers?

> This is a vapor format until now, just reserved for the future
> implementation :)

It may make sense to handle this in a similar way to MP3s and so on -
the Intel guys were working on generalising the interface in their out
of tree driver to be usable for other things, though they've not posted
anything yet.

Re: Query about SNDRV_PCM_FORMAT_GSM

[Takashi Iwai]

At Wed, 22 Jun 2011 12:58:33 +0100,
Mark Brown wrote:
> 
> On Wed, Jun 22, 2011 at 11:54:56AM +0200, Takashi Iwai wrote:
> > Patrick Lai wrote:
> 
> > > I see SNDRV_PCM_FORMAT_GSM is defined in asound.h. However, I do not
> > > find any reference to this macro except pcm_misc.c. I am curious how
> > > bps info(i.e 4.75 kbit/s) is passed down to the ALSA driver. Any
> > > pointers?
> 
> > This is a vapor format until now, just reserved for the future
> > implementation :)
> 
> It may make sense to handle this in a similar way to MP3s and so on -
> the Intel guys were working on generalising the interface in their out
> of tree driver to be usable for other things, though they've not posted
> anything yet.

Yeah, this has been worked since years ago, so it'd be great if it
comes out finally.  Then we need to settle down the proper definition
of these non-standard formats.


Takashi