[alsa-devel] [PATCH] ASoC: s3c24xx platform: Fix s3c2410_dma_started called at wrong time

Mark Brown broonie at opensource.wolfsonmicro.com
Thu Aug 20 14:18:51 CEST 2009

On Thu, Aug 20, 2009 at 07:59:48PM +0800, Shine Liu wrote:
> On Thu, 2009-08-20 at 11:15 +0100, Mark Brown wrote:

> > incorrect :) Another option is to provide a callback in the private data
> > passed to the DMA driver which the DMA driver can call at the
> > appropriate point during setup.

> arrived which is generated by the IIS. DMA driver has no way to know
> when the DMA REQ signal arrived. So the s3c24xx DMA driver provids a
> s3c2410_dma_started() method to let the user call when he knows the DMA
> transfer has been started.

Yes, I understand the problem.  The callback I suggest above ought to
allow the appropriate sequencing - the DMA driver can call the callback
to start the DAI in between starting the DMA and kicking the DMA API to
queue the next block.  That would avoid the abstraction problems.

More information about the Alsa-devel mailing list