On Wed, Aug 26, 2020 at 8:22 AM Lars-Peter Clausen <lars@xxxxxxxxxx> wrote:
>
> From: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
>
> A transfer may fall shorter than the bytes in the block.
> This information is available in the residue from the DMA engine, so we can
> compute actual `bytes_used` with that by subtracting the residue.
>
This was in my pipeline as well [obviously].
Thanks :)
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
> ---
> drivers/iio/buffer/industrialio-buffer-dmaengine.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iio/buffer/industrialio-buffer-dmaengine.c b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> index 6dedf12b69a4..5789bda0745b 100644
> --- a/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> +++ b/drivers/iio/buffer/industrialio-buffer-dmaengine.c
> @@ -45,7 +45,8 @@ static struct dmaengine_buffer *iio_buffer_to_dmaengine_buffer(
> return container_of(buffer, struct dmaengine_buffer, queue.buffer);
> }
>
> -static void iio_dmaengine_buffer_block_done(void *data)
> +static void iio_dmaengine_buffer_block_done(void *data,
> + const struct dmaengine_result *result)
> {
> struct iio_dma_buffer_block *block = data;
> unsigned long flags;
> @@ -53,6 +54,7 @@ static void iio_dmaengine_buffer_block_done(void *data)
> spin_lock_irqsave(&block->queue->list_lock, flags);
> list_del(&block->head);
> spin_unlock_irqrestore(&block->queue->list_lock, flags);
> + block->bytes_used -= result->residue;
> iio_dma_buffer_block_done(block);
> }
>
> @@ -74,7 +76,7 @@ static int iio_dmaengine_buffer_submit_block(struct iio_dma_buffer_queue *queue,
> if (!desc)
> return -ENOMEM;
>
> - desc->callback = iio_dmaengine_buffer_block_done;
> + desc->callback_result = iio_dmaengine_buffer_block_done;
> desc->callback_param = block;
>
> cookie = dmaengine_submit(desc);
> --
> 2.20.1
>
