Re: [PATCH 1/1] media: m2m-deinterlace: replace direct ->device_prep*() calls with standard DMA engine API

[Laurent Pinchart]

On Thu, Sep 17, 2026 at 03:04:16PM -0400, Frank.Li@xxxxxxxxxxx wrote:
> From: Frank Li <Frank.Li@xxxxxxx>
> 
> DMA engine consumers must not call the channel's device_prep_*() function
> pointers directly. Use the standard dmaengine wrapper APIs instead.
> 
> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

I've checked the other DMA operations, and there are a few direct
callers of .device_prep_dma_memcpy() and .device_prep_slave_sg(). The
former should be easy to address, as the dmaengine_prep_dma_memcpy()
wrapper is a drop-in replacement. The latter may be a bit more
complicated.

Any volunteer to send patches ? :-)

> ---
>  drivers/media/platform/m2m-deinterlace.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/m2m-deinterlace.c b/drivers/media/platform/m2m-deinterlace.c
> index 9dcc4bd6cbdd5..57a91ff2269f2 100644
> --- a/drivers/media/platform/m2m-deinterlace.c
> +++ b/drivers/media/platform/m2m-deinterlace.c
> @@ -330,7 +330,7 @@ static void deinterlace_issue_dma(struct deinterlace_ctx *ctx, int op,
>  	ctx->xt->dst_sgl = true;
>  	flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
>  
> -	tx = dmadev->device_prep_interleaved_dma(chan, ctx->xt, flags);
> +	tx = dmaengine_prep_interleaved_dma(chan, ctx->xt, flags);
>  	if (tx == NULL) {
>  		v4l2_warn(&pcdev->v4l2_dev, "DMA interleaved prep error\n");
>  		return;

-- 
Regards,

Laurent Pinchart