Re: [PATCH 0/6] dmaengine: Add common dma_slave_config and split it into src and dst parts

[Frank Li]

On Tue, Mar 17, 2026 at 03:56:40PM +0530, Vinod Koul wrote:
> On 09-03-26, 10:27, Frank Li wrote:
> > On Mon, Mar 09, 2026 at 12:24:33PM +0100, Vinod Koul wrote:
> > > On 14-01-26, 12:12, Frank Li wrote:
> > > > Many DMA engine drivers store a dma_slave_config per channel. Propagate
> > > > this configuration into struct dma_chan to avoid duplicating the same
> > > > code in each driver.
> > > >
> > > > Much of dma_slave_config is identical for source and destination. Split
> > > > the configuration into src and dst groups and use a union to preserve
> > > > backward compatibility. This reduces the need for drivers to repeatedly
> > > > check the DMA transfer direction.
> > >
> > > The reason why we had both the src/dstn sides was intended method to
> > > allow upport ofr device to device dma. Some interest was shown for that
> > > at that time.
> > > I dont think we have such a user even now...
> >
> > My means is the field name is identical, not value identical although most
> > case is the identical. but it is possible, especial FIFO space windows,
> >
> > sound/soc/fsl/fsl_asrc_dma.c use DEV_TO_DEV, at least src and addr use
> > differece address.
>
> Yeah so this would break if we go ahead. Thanks for looking this up

Sorry, what break? This patch just group these informations.

Frank

>
> --
> ~Vinod