On Fri, Jan 11, 2013 at 11:40:41AM +0000, Arnd Bergmann wrote: > On Friday 11 January 2013, Matt Porter wrote: > > The approach taken is similar to how OMAP DMA is being converted to > > DMA Engine support. With the functional EDMA private API already > > existing in mach-davinci/dma.c, we first move that to an ARM common > > area so it can be shared. Adding DT and runtime PM support to the > > private EDMA API implementation allows it to run on AM33xx. AM33xx > > only boots using DT so we leverage Jon's generic DT DMA helpers to > > register EDMA DMAC with the of_dma framework and then add support > > for calling the dma_request_slave_channel() API to both the mmc > > and spi drivers. > > I think this looks very good. What I wonder is whether we should > make the non-DT parts of the dmaengine driver compile-time > conditional on CONFIG_ATAGS though, so the slave drivers don't > have a link-time dependency on the dmaengine driver's > omap_dma_filter_fn symbol when building without ATAGS support. We have tightly coupled the link-time dependency for omap_dma_filter_fn by going down the path of using dma_request_slave_channel_compat() as Tony suggested to avoid extra ifdefry. That dependency will go away naturally if all the "legacy" OMAP platforms were required to only boot from DT...just as a newly added SoCs are. Are you suggesting unwinding the _compat() approach? -Matt -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
