[alsa-devel] [PATCH 01/11] dma: imx-sdma: make channel0 operations atomic

Vinod Koul vinod.koul at linux.intel.com
Fri Apr 27 12:22:10 CEST 2012

On Fri, 2012-04-27 at 16:41 +0800, Richard Zhao wrote:
> On Fri, Apr 27, 2012 at 01:51:40PM +0530, Vinod Koul wrote:
> > On Fri, 2012-04-27 at 15:02 +0800, Richard Zhao wrote:
> > > device_prep_dma_cyclic may be call in audio trigger function which is
> > > atomic context, so we make it atomic too.
> > No this is wrong behavior. You should not call dma prepare functions in
> > any of the sound trigger calls. It would make sense to move this in
> > sound prepare callback.
> Then, could you please doc it somewhere? I think I'm not the only one
> confused.
See the soc-dmaengine.c for correct behavior!
I can document only dmaengine behavior (which is already there) and not
how each subsystem should use this. People is subsystems need to see how
to use the dmaengine APIs sanely


More information about the Alsa-devel mailing list