On Tue, Apr 10, 2018 at 03:46:03PM +0800, Baolin Wang wrote:
> From: Eric Long <eric.l...@spreadtrum.com>
>
> Define the DMA transfer step type to make code more readable.
>
> Signed-off-by: Eric Long <eric.l...@spreadtrum.com>
> Signed-off-by: Baolin Wang <baolin.w...@linaro.org>
> ---
> drivers/dma/sprd-dma.c | 28 ++++++++++++++++++++++------
> 1 file changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
> index b106e8a..af9c156 100644
> --- a/drivers/dma/sprd-dma.c
> +++ b/drivers/dma/sprd-dma.c
> @@ -169,6 +169,22 @@ enum sprd_dma_int_type {
> SPRD_DMA_CFGERR_INT,
> };
>
> +/*
> + * enum sprd_dma_step: define the DMA transfer step type
> + * @SPRD_DMA_NONE_STEP: transfer do not need step
> + * @SPRD_DMA_BYTE_STEP: transfer step is one byte
> + * @SPRD_DMA_SHORT_STEP: transfer step is two bytes
> + * @SPRD_DMA_WORD_STEP: transfer step is one word
> + * @SPRD_DMA_DWORD_STEP: transfer step is double word
> + */
> +enum sprd_dma_step {
looking at bit defines, does it need to be enum? a #define would just be fine.
> + SPRD_DMA_NONE_STEP,
> + SPRD_DMA_BYTE_STEP = BIT(0),
> + SPRD_DMA_SHORT_STEP = BIT(1),
> + SPRD_DMA_WORD_STEP = BIT(2),
> + SPRD_DMA_DWORD_STEP = BIT(3),
> +};
> +
> /* dma channel hardware configuration */
> struct sprd_dma_chn_hw {
> u32 pause;
> @@ -598,16 +614,16 @@ static int sprd_dma_config(struct dma_chan *chan,
> struct sprd_dma_desc *sdesc,
>
> if (IS_ALIGNED(len, 4)) {
> datawidth = 2;
> - src_step = 4;
> - des_step = 4;
> + src_step = SPRD_DMA_WORD_STEP;
> + des_step = SPRD_DMA_WORD_STEP;
> } else if (IS_ALIGNED(len, 2)) {
> datawidth = 1;
> - src_step = 2;
> - des_step = 2;
> + src_step = SPRD_DMA_SHORT_STEP;
> + des_step = SPRD_DMA_SHORT_STEP;
> } else {
> datawidth = 0;
> - src_step = 1;
> - des_step = 1;
> + src_step = SPRD_DMA_BYTE_STEP;
> + des_step = SPRD_DMA_BYTE_STEP;
> }
>
> fragment_len = SPRD_DMA_MEMCPY_MIN_SIZE;
> --
> 1.7.9.5
>
--
~Vinod
