[PATCH V7 3/3] dma: add Qualcomm Technologies HIDMA channel driver
vinod.koul at intel.com
Fri Dec 11 01:35:02 PST 2015
On Thu, Dec 10, 2015 at 03:10:48PM -0500, Sinan Kaya wrote:
> On 12/5/2015 3:00 AM, Vinod Koul wrote:
> > On Wed, Dec 02, 2015 at 02:04:05PM -0500, Sinan Kaya wrote:
> >>>>> You are missing the point. Channel can be paused, yes but the descriptor
> >>>>> is in queue and is not paused. The descriptor running is paused, yes.
> >>>>> There is subtle difference between these
> >>> I'll follow your recommendation. PAUSE for the currently active
> >>> descriptor and DMA_IN_PROGRESS for the rest.
> >> I'm now confused.
> >> I looked at several DMA driver implementations.
> >> 1. They call dma_cookie_status function to see if the job is done.
> >> 2. If done, they return right ahead.
> >> 3. Otherwise, dma_cookie_status returns DMA_IN_PROGRESS.
> >> 4. Next the code checks if the channel is paused and return value is
> >> DMA_IN_PROGRESS. The code changes return code to DMA_PAUSED.
> >> Whereas, I was returning paused first before even checking if the
> >> descriptor is done. Are you OK with the sequence 1..4 above?
> > Yes am okay with this with slight change in 4.
> > You should set to PAUSED only for current descriptor and not for the ones in
> > queue
> OK. I'll post a new version with this. Is there any other comment that
> needed to be addressed?
Looks okay to me
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