On Mon, 3 Apr 2023 17:47:54 +0200 Paul Cercueil paul@crapouillou.net wrote:
Update the devm_iio_dmaengine_buffer_setup() function to support specifying the buffer direction.
Update the iio_dmaengine_buffer_submit() function to handle input buffers as well as output buffers.
Signed-off-by: Paul Cercueil paul@crapouillou.net Reviewed-by: Alexandru Ardelean ardeleanalex@gmail.com
Just one trivial question inline.
Jonathan
diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c index 5f85ba38e6f6..592d2aa9044c 100644 --- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c +++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c @@ -64,14 +64,25 @@ static int iio_dmaengine_buffer_submit_block(struct iio_dma_buffer_queue *queue, struct dmaengine_buffer *dmaengine_buffer = iio_buffer_to_dmaengine_buffer(&queue->buffer); struct dma_async_tx_descriptor *desc;
- enum dma_transfer_direction dma_dir;
- size_t max_size; dma_cookie_t cookie;
- block->bytes_used = min(block->size, dmaengine_buffer->max_size);
- block->bytes_used = round_down(block->bytes_used,
dmaengine_buffer->align);
- max_size = min(block->size, dmaengine_buffer->max_size);
- max_size = round_down(max_size, dmaengine_buffer->align);
- if (queue->buffer.direction == IIO_BUFFER_DIRECTION_IN) {
block->bytes_used = max_size;dma_dir = DMA_DEV_TO_MEM;- } else {
dma_dir = DMA_MEM_TO_DEV;- }
- if (!block->bytes_used || block->bytes_used > max_size)
return -EINVAL;
Two paths to here. Either DIRECTION_IN in which we just set things up so conditions being checked are always fine (unless max_size == 0? Can that happen?), or !DIRECTION_IN. So why not move this into the else {} branch above?
desc = dmaengine_prep_slave_single(dmaengine_buffer->chan,
block->phys_addr, block->bytes_used, DMA_DEV_TO_MEM,
block->phys_addr, block->bytes_used, dma_dir,