Re: [PATCH v3 02/15] dmaengine: omap: Add support for pause/resumein cyclic dma mode

From: Russell King - ARM Linux
Date: Tue Sep 18 2012 - 04:29:16 EST


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.
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