Re: [PATCH 2/3] dmaengine: plx_dma: Remove obsolete 32-bit DMA mask fallback

[Frank Li]

On Thu, Sep 03, 2026 at 07:54:40PM +0800, Ruizhe Zhou wrote:
> The DMA API guarantees support for masks of 32 bits or wider and
> explicitly identifies retrying a 32-bit mask after a wider request as
> incorrect:
> https://docs.kernel.org/core-api/dma-api-howto.html#dma-addressing-capabilities
>
> Remove the obsolete fallback while retaining the error check so that a
> genuine DMA setup failure is still propagated and aborts initialization.
>
> Signed-off-by: Ruizhe Zhou <zhouruizhe@xxxxxxxxxxx>
> ---

Eventhough needn't check when 48bit, but remove fallback is correct.

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

>  drivers/dma/plx_dma.c | 2 --
>  1 file changed, 2 deletions(-)
>
> diff --git a/drivers/dma/plx_dma.c b/drivers/dma/plx_dma.c
> index 84941a918b01..ad9187448ed2 100644
> --- a/drivers/dma/plx_dma.c
> +++ b/drivers/dma/plx_dma.c
> @@ -562,8 +562,6 @@ static int plx_dma_probe(struct pci_dev *pdev,
>  		return rc;
>
>  	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(48));
> -	if (rc)
> -		rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
>  	if (rc)
>  		return rc;
>
> --
> 2.27.0
>