[alsa-devel] [PATCH v3 02/15] dmaengine: omap: Add support for pause/resume in cyclic dma mode

[Russell King - ARM Linux]

On Mon, Sep 17, 2012 at 08:43:57AM +0530, Vinod Koul wrote:
> On Fri, 2012-09-14 at 15:05 +0300, Peter Ujfalusi wrote:
> > -       /* FIXME: not supported by platform private API */
> > -       return -EINVAL;
> > +       /* Pause/Resume only allowed with cyclic mode */
> > +       if (!c->cyclic)
> > +               return -EINVAL; 
> This is not a dma restriction right?

This is needed because this is not a real "pause" - it is a stop, which
causes the contents of the DMA engine's FIFOs to be discarded - which
means a subsequent resume will loose data.