[PATCH V2] dmaengine: qcom_hidma: correct API violation for submit
Vinod Koul
vinod.koul at intel.com
Sun Jul 2 22:10:22 PDT 2017
On Fri, Jun 30, 2017 at 10:43:05AM -0400, Sinan Kaya wrote:
> Current code is violating the DMA Engine API by putting the submitted
> requests directly into the HW queue. This causes queued transactions
> to be started by another thread as soon as the first one finishes.
>
> The DMA Engine document clearly states this.
>
> "dmaengine_submit() will not start the DMA operation".
>
> Move HW queuing of the requests into the issue_pending() routine
> to comply with API requirements also create a new queued state for
> temporarily holding the requests.
>
> A descriptor goes through these transitions now.
>
> free->prepared->queued->active->completed->free
>
> as opposed to
>
> free->prepared->active->completed->free
Applied, thanks
--
~Vinod
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