On Mon, Jun 11, 2012 at 10:20:49AM +0530, Vinod Koul wrote: > I think it is a good idea. And I would like to extend it even a little > bit. Do we have any users of peripheral to peripheral slave dma? > IIRC that is not the case, or does anyone know of existence or plans > for such a h/w? > > If not, lets junk the src/dst fields and keep burst, length, addr fields > which point to the peripheral values. > > Alternatively if we need both, then we can't have union and Russell's > idea seems good one :) We don't need the union whatever way that goes. The question over whether we have the src/dst fields is whether we want to support a different configuration for DMA_DEV_TO_MEM/DMA_MEM_TO_DEV without having to reconfigure the channel each time its direction is switched. Out of the following users: drivers/mmc/host/mmci.c drivers/spi/spi-pl022.c drivers/tty/serial/amba-pl011.c with amba-pl08x, I don't see any which set a different configuration depending on direction, and sa11x0 and OMAP DMA engine drivers only support one direction per channel. So, the question really comes down to whether we _want_ to support this, and how painful it would be to re-introduce this if we did need it. Maybe the right answer is to use the control command value to sort that out when we come to it. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
