Re: [RFC v2] dmaengine: omap-dma: Start DMA without delay forcyclic channels

From: Tony Lindgren
Date: Mon Apr 08 2013 - 13:16:20 EST


* Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> [130408 10:15]:
> On Mon, Apr 08, 2013 at 09:11:04AM +0200, Peter Ujfalusi wrote:
> > Russell,
> >
> > On 04/03/2013 01:17 PM, Peter Ujfalusi wrote:
> > > cyclic DMA is only used by audio which needs DMA to be started without a
> > > delay.
> > > If the DMA for audio is started using the tasklet we experience random
> > > channel switch (to be more precise: channel shift).
> > >
> > > Reported-by: Peter Meerwald <pmeerw@xxxxxxxxxx>
> > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> > > ---
> > > Hi Russell,
> > >
> > > Instead of removing the tasklet we can identify the DMA channel used by audio
> > > based on the cyclic flag of the channel.
> > > I think this can be used as a short term solution to fix the audio channel shift
> > > issue and later when we have the dynamic DMA channel allocation we can adjust
> > > the code.
> >
> > Could you, please look at this patch?
>
> Now that I'm back from a short 4 day break, then yes, and the answer is
> that it's fine. Who's handling the patch?

I suggest Peter resend the patch with also Grant + Linus W cc:d so
they can queue it unless there are other related patches pending
somewhere else.

Regards,

Tony
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