[PATCH] dmaengine: pl330: Set residue in tx_status callback

Jassi Brar jaswinder.singh at linaro.org
Thu Mar 12 01:47:25 PDT 2015

Hi Vinod, Hi Russell,

On 11 December 2014 at 11:42, Jassi Brar <jaswinder.singh at linaro.org> wrote:
> On 11 December 2014 at 10:17, Vinod Koul <vinod.koul at intel.com> wrote:
>> On Tue, Dec 09, 2014 at 08:48:04PM +0530, Jassi Brar wrote:
>>> As Russell pointed out, that ain't the case either.
>>> So we are yet to figure out benefits of having explicit
>>> issue_pending() after tx_submit().
>> callback ?
> The callback is set after prep() and before tx_submit(), but here we
> talk after tx_submit().

Perhaps the idea dates back to async-only days, when client drivers
would prepare and queue descriptors in the controller driver rather
than having to manage the dependency queues themselves (?).

 Today ~95% clients are slave and I am yet to find one that really
can't work with submit and issue_pending tied together. Not to forget
the 100% of the controller drivers have to manage 'submitted' and
'active' queues -- only to have arguably negative side-effects.

If we agree that clubbing submit and issue_pending is the right thing
to do, I can start converting the ~90 client drivers. Please let me
know either way.


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