Re: [PATCH 08/11] dmaengine: xilinx_dpdma: stop using slave_id field

From: Arnd Bergmann
Date: Mon Nov 15 2021 - 08:43:35 EST


On Mon, Nov 15, 2021 at 2:05 PM Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
> On Mon, Nov 15, 2021 at 01:38:07PM +0100, Arnd Bergmann wrote:
> > On Mon, Nov 15, 2021 at 12:49 PM Laurent Pinchart wrote:
> >
> > Right. I wonder if there is even a point in using the dmaengine API
> > in that case, I think for other single-purpose drivers we tend to just
> > integrate the functionality in the client driver. No point changing this
> > now of course, but it does feel odd.
>
> I agree, and that's what I would have done as well, if it wasn't for the
> fact that the DMA engine also supports a second client for audio. This
> isn't supported in upstream yet. We could still have created an ad-hoc
> solution, possibly based on the components framework, but the DMA engine
> subsystem wasn't a bad fit.

Ah, makes sense. In this case, I guess the data could have been
part of the DMA specifier after all, in a second cell after the
channel number.

Arnd