Messages in this thread | | | Date | Mon, 10 Oct 2011 14:46:20 +0530 | Subject | Re: [PATCHv4] DMAEngine: Define interleaved transfer request api | From | Jassi Brar <> |
| |
On 10 October 2011 12:23, Vinod Koul <vinod.koul@intel.com> wrote: > > +struct dmaxfer_memcpy_template { > + dma_addr_t src_start; > + dma_addr_t dst_start; > + bool src_inc; > + bool dst_inc; > + bool src_sgl; > + bool dst_sgl; > + size_t numf; > + size_t frame_size; > + struct data_chunk sgl[0]; > +}; > + > +struct dmaxfer_slave_template { > + dma_addr_t mem; > + bool mem_inc; > + size_t numf; > + size_t frame_size; > + struct data_chunk sgl[0]; > +}; > (1) Please tell how is dmaxfer_slave_template supposed to work on bi-directional channels? Keeping in mind, dma_slave_config.direction is marked to go away in future.
(2) * slave_template.mem <=> memcpy_template.src_start * slave_template.mem_inc <=> memcpy_template.src_inc
So essentially memcpy_template := slave_template + src/dst_sgl + dst_start + dst_inc
Even after this separation, there is nothing slave specific in dmaxfer_slave_template. The slave client still needs DMA_SLAVE_CONFIG to specify slave parameters of the transfer. You only save a few bytes in a _copy_ of memcpy_template.
Sorry but I only see code duplication and a very vulnerable segregation.
> > The point is that it makes it simpler to understand what we are doing > rather than resort to parsing to find out if its memcpy or slave and > what is the direction. > Not sure how reading dmaxfer_template.xfer_direction is "parsing". -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |