Re: [PATCH] dmaengine: mv_xor: use devm_platform_ioremap_resource()

[Frank Li]

On Mon, Jul 13, 2026 at 05:28:03PM -0700, Rosen Penev wrote:
> Replace the two open-coded platform_get_resource() plus devm_ioremap()
> sequences with devm_platform_ioremap_resource() for the low and high XOR
> register windows. This folds the resource lookup and mapping into a
> single call and returns an ERR_PTR on failure, checked with IS_ERR() and
> propagated via PTR_ERR().
>
> devm_platform_ioremap_resource() reserves the region via
> devm_request_mem_region(), which requires non-overlapping reg ranges. All
> XOR nodes in the Marvell DTS describe two distinct 0x100 register windows
> that do not overlap each other, and sibling XOR nodes interleave without
> overlapping, so the newly-reserving mapping introduces no region
> conflict.
>
> Built for ARM (defconfig + CONFIG_MV_XOR) with LLVM=1;
> drivers/dma/mv_xor.o compiles cleanly.

Nit: suppose pass build is neccesary steps before post patch. So needn't
mention it commit message.

Reviewed-by: Frank Li <Frank.Li@xxxxxxx>

>
> Assisted-by: opencode:hy3-free
> Signed-off-by: Rosen Penev <rosenp@xxxxxxxxx>
> ---
>  drivers/dma/mv_xor.c | 23 ++++++-----------------
>  1 file changed, 6 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c
> index 25ed61f1b089..fe2e6b9ec185 100644
> --- a/drivers/dma/mv_xor.c
> +++ b/drivers/dma/mv_xor.c
> @@ -1309,7 +1309,6 @@ static int mv_xor_probe(struct platform_device *pdev)
>  	const struct mbus_dram_target_info *dram;
>  	struct mv_xor_device *xordev;
>  	struct mv_xor_platform_data *pdata = dev_get_platdata(&pdev->dev);
> -	struct resource *res;
>  	unsigned int max_engines, max_channels;
>  	int i, ret;
>
> @@ -1319,23 +1318,13 @@ static int mv_xor_probe(struct platform_device *pdev)
>  	if (!xordev)
>  		return -ENOMEM;
>
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	if (!res)
> -		return -ENODEV;
> +	xordev->xor_base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(xordev->xor_base))
> +		return PTR_ERR(xordev->xor_base);
>
> -	xordev->xor_base = devm_ioremap(&pdev->dev, res->start,
> -					resource_size(res));
> -	if (!xordev->xor_base)
> -		return -EBUSY;
> -
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> -	if (!res)
> -		return -ENODEV;
> -
> -	xordev->xor_high_base = devm_ioremap(&pdev->dev, res->start,
> -					     resource_size(res));
> -	if (!xordev->xor_high_base)
> -		return -EBUSY;
> +	xordev->xor_high_base = devm_platform_ioremap_resource(pdev, 1);
> +	if (IS_ERR(xordev->xor_high_base))
> +		return PTR_ERR(xordev->xor_high_base);
>
>  	platform_set_drvdata(pdev, xordev);
>
> --
> 2.55.0
>