Hi Vinod, I've been writing the dmaengine slave driver for pxa architecture lately. I have only one remaining concern with descriptors reusing, and I need your input. My usecase is as follows, from a driver point of view : - tx = dmaengine_prep_slave_sg(dma_chan, sg, sglen, DMA_PREP_CONTINUE); - dma_map_sg(dev, sg, sglen, DMA_DEV_TO_MEM) - dmaengine_submit(tx) - dma_async_issue_pending(dma_chan); - ... wait for tx->callback() => here, because of DMA_PREP_CONTINUE, the hardware descriptors are not freed, as what I need to reuse - dma_sync_sg_for_cpu(dev, sg, sglen, ) - copy video buffer somewhere (or not if frame interleaving) - dmaengine_submit(tx) - dma_async_issue_pending(dma_chan) => the video buffer is captured again, so far so good - ... wait for tx->callback() And here comes my question : how do I free the hardware descriptors for tx now ? As I chose to not free them upon tx completion, is there an API call to do it ? Cheers. -- Robert -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
