Re: [PATCH 1/8] dmaengine: ptdma: unmap descriptor before completing cookie

[Frank Li <Frank.li@oss.nxp.com>]

On Sat, Oct 10, 2026 at 02:43:39PM +0200, Wolfram Sang wrote:
> To ensure that buffers are flushed, make sure that the descriptor gets
> unmapped before completing the cookie.
>
> Link: https://lore.kernel.org/r/20261009093745.539924-1-vkoul@kernel.org
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>  drivers/dma/amd/ptdma/ptdma-dmaengine.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/amd/ptdma/ptdma-dmaengine.c b/drivers/dma/amd/ptdma/ptdma-dmaengine.c
> index 628c49ce5de9..7f51d1e6c727 100644
> --- a/drivers/dma/amd/ptdma/ptdma-dmaengine.c
> +++ b/drivers/dma/amd/ptdma/ptdma-dmaengine.c
> @@ -224,8 +224,8 @@ static struct pt_dma_desc *pt_handle_active_desc(struct pt_dma_chan *chan,
>  				if (desc->status != DMA_ERROR)
>  					desc->status = DMA_COMPLETE;
>
> -				dma_cookie_complete(tx_desc);
>  				dma_descriptor_unmap(tx_desc);
> +				dma_cookie_complete(tx_desc);

I think we should consider add new APIs/Helper, such as

dmaengine_unmap_and_cookie_complete(), which do both works.

Frank

>  				list_del(&desc->vd.node);
>  			} else {
>  				/* Don't handle it twice */
> @@ -362,8 +362,8 @@ static void pt_cmd_callback_work(void *data, int err)
>  		if (desc->status != DMA_ERROR)
>  			desc->status = DMA_COMPLETE;
>
> -		dma_cookie_complete(tx_desc);
>  		dma_descriptor_unmap(tx_desc);
> +		dma_cookie_complete(tx_desc);
>  	} else {
>  		tx_desc = NULL;
>  	}
> --
> 2.53.0
>