uaudio patch, configurable buffer size

Mathew Kanner mat at
Tue Mar 8 12:08:51 GMT 2005

On Mar 07, Kazuhito HONDA wrote:
> Hello,
> From: Pyun YongHyeon <yongari at>
> Subject: Re: uaudio patch, configurable buffer size
> Date: Mon, 7 Mar 2005 12:04:19 +0900
> > AFAIK, we already have format converter in kernel.
> > See feeder_fmt.c. The converter detects differences between hardware
> > capabilities and audio samples and automatically converts it(e.g.
> > big endian <->little endian, mono <-> stereo, signed <-> unsigned,
> > ulaw<->alow etc).
> Ah, I haven't found it for a long time.  
> I tried to change the caps in uaudio_pcm.c, 
> and a sampling rate can be converted correctly as you wrote.

	Hi Kazuhito,
	Sorry about referring to you in the third person in other
e-mails :)

	I'm presently working on moving the ua_playcaps and ua_reccaps
into struct ua_info instead of global variables.  You'll notice that
we do a uaudio_query_formats, which should be at device attach and if
we add a query for the min/max speed, it should be sufficient .  I
hope to have it done in few days but if you beet me to the punch we
can commit it.


> I'll challenge to use this converter in uaudio, too.
> If I or someone will succeed in it, 
> I'll write to PR usb/78028 that it should be closed except applied.


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