Re: [PATCH v5 1/3] dmaengine: xilinx_dma: Check for channel idle state before submitting dma descriptor

From: Vinod Koul
Date: Fri Jan 13 2017 - 00:32:52 EST


On Fri, Jan 13, 2017 at 04:28:11AM +0000, Appana Durga Kedareswara Rao wrote:
> Hi Vinod,
>
> Thanks for the review...
> >
> > On Sat, Jan 07, 2017 at 12:15:28PM +0530, Kedareswara rao Appana wrote:
> > > Add channel idle state to ensure that dma descriptor is not
> > > submitted when VDMA engine is in progress.
> >
> > any reason why you want to make your own varible and not use the HW to
> > query
> > as done earlier. It is not clear to me why that is removed from description
>
> We need to poll for a bit in the status register to know the dma state.
> We are currently doing that in the driver hot path
> To avoid this using own variables.

It would be worthwhile to document these, down the line people may not
remeber the motivation


--
~Vinod