[alsa-devel] Basic DMA question

[Rene Herman]

On 03/28/2007 12:16 PM, Takashi Iwai wrote:

> At Mon, 26 Mar 2007 11:28:59 +0200,
> Sven Johnsson wrote:

>> Rene,
>>
>> I have already read the ALSA driver document. What I really like to
>> understand is when DMA transfers are invoked, and what the source and
>> destination for the transfer is.
> 
> The DMA transfer is started/stopped in trigger callback.
> In the case of typical playback, the source is the buffer the driver
> allocated (in hw_params callback) and the destination is the
> hardware.  The DMA setup is usually done in prepare callback.

Oh, sorry... had to look at this one before answering but then forgot 
about it while looking at a local capture problem.

Rene.