Re: [PATCH v2 1/3] dmaengine: add DMA_PREP_CMD for non-Data descriptors.

Abhishek Sahu
2017-07-17T09:24:24Z

On 2017-06-26 18:19, Abhishek Sahu wrote:
> Some of the DMA controllers are capable of issuing the commands
> to peripheral by the DMA. These commands can be list of register
> reads/writes and its different from normal data reads/writes.
> This patch adds new flag DMA_PREP_CMD in DMA API which tells
> the driver that the data passed to DMA API is in command format
> and DMA driver will form descriptor in the required format.
>
> This flag can be used by any DMA controller driver which requires
> special handling for non-Data descriptors.
>
> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
> ---
> include/linux/dmaengine.h | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
> index 5336808..bbc297e 100644
> --- a/include/linux/dmaengine.h
> +++ b/include/linux/dmaengine.h
> @@ -186,6 +186,8 @@ struct dma_interleaved_template {
> * on the result of this operation
> * @DMA_CTRL_REUSE: client can reuse the descriptor and submit again
> till
> * cleared or freed
> + * @DMA_PREP_CMD: tell the driver that the data passed to DMA API is
> in command
> + * format and it will be used for configuring the peripheral
> registers.
> */
> enum dma_ctrl_flags {
> DMA_PREP_INTERRUPT = (1 << 0),
> @@ -195,6 +197,7 @@ enum dma_ctrl_flags {
> DMA_PREP_CONTINUE = (1 << 4),
> DMA_PREP_FENCE = (1 << 5),
> DMA_CTRL_REUSE = (1 << 6),
> + DMA_PREP_CMD = (1 << 7),

Hi Vinod/Dan,

Could you please help in reviewing these DMA patches.
I have posted QPIC NAND support patches which are dependent
upon these DMA patches.

https://www.spinics.net/lists/kernel/msg2545386.html

> };
>
> /**

--
Abhishek Sahu