Hi Scott, Thanks for the reply.
> > > > the question is this; is the dma_async_memcpy_buf_to_buf() function > > intended to be bi-directional and is it safe to pass it a 'src' pointer > > that's actually coming from the device, or does there need to be a second > > function for doing a copy from the device to the CPU? > > The "device" is the DMA engine, thus src is inherently going to the > device and dest is inherently coming from the device. > Yes, I understand the directions and what they apply to, that's obvious from the macros themselves. What I don't understand is if it's safe, from a kernel/cache standpoint, to pass to the function a src pointer coming _from_ the device and a dest pointer that's going _to_ the device? In other words, can I use this function to _write_ to a DMA slave? If not, there's a functionality missing from the async DMA engine. Thanks. Bruce _______________________________________________ Linuxppc-embedded mailing list [email protected] https://ozlabs.org/mailman/listinfo/linuxppc-embedded
