Re: [PATCH] dmaengine: owl-dma: fix clang -Wvoid-pointer-to-enum-cast warning

From: Manivannan Sadhasivam
Date: Thu Aug 17 2023 - 02:57:29 EST


On Wed, Aug 16, 2023 at 08:12:50PM +0000, Justin Stitt wrote:
> When building with clang 18 I see the following warning:
> | drivers/dma/owl-dma.c:1119:14: warning: cast to smaller integer type
> | 'enum owl_dma_id' from 'const void *' [-Wvoid-pointer-to-enum-cast]
> | 1119 | od->devid = (enum owl_dma_id)of_device_get_match_data(&pdev->dev);
>
> This is due to the fact that `of_device_get_match_data()` returns a
> void* while `enum owl_dma_id` has the size of an int.
>
> Cast result of `of_device_get_match_data()` to a uintptr_t to silence
> the above warning for clang builds using W=1
>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1910
> Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> Signed-off-by: Justin Stitt <justinstitt@xxxxxxxxxx>

Acked-by: Manivannan Sadhasivam <mani@xxxxxxxxxx>

- Mani

> ---
> drivers/dma/owl-dma.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/owl-dma.c b/drivers/dma/owl-dma.c
> index b6e0ac8314e5..f340a04579f4 100644
> --- a/drivers/dma/owl-dma.c
> +++ b/drivers/dma/owl-dma.c
> @@ -1116,7 +1116,7 @@ static int owl_dma_probe(struct platform_device *pdev)
> dev_info(&pdev->dev, "dma-channels %d, dma-requests %d\n",
> nr_channels, nr_requests);
>
> - od->devid = (enum owl_dma_id)of_device_get_match_data(&pdev->dev);
> + od->devid = (uintptr_t)of_device_get_match_data(&pdev->dev);
>
> od->nr_pchans = nr_channels;
> od->nr_vchans = nr_requests;
>
> ---
> base-commit: 2ccdd1b13c591d306f0401d98dedc4bdcd02b421
> change-id: 20230816-void-drivers-dma-owl-dma-41b95a098275
>
> Best regards,
> --
> Justin Stitt <justinstitt@xxxxxxxxxx>
>

--
மணிவண்ணன் சதாசிவம்