Re: [PATCH] serial: mxs-uart: fix Wvoid-pointer-to-enum-cast warning

From: Greg Kroah-Hartman
Date: Thu Aug 10 2023 - 11:44:24 EST


On Thu, Aug 10, 2023 at 10:50:42AM +0200, Krzysztof Kozlowski wrote:
> `devtype` is enum, thus cast of pointer on 64-bit compile test with W=1
> causes:
>
> mxs-auart.c:1598:15: error: cast to smaller integer type 'enum mxs_auart_type' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
>
> Cc: Andi Shyti <andi.shyti@xxxxxxxxxx>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
> ---
> drivers/tty/serial/mxs-auart.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
> index 8eeecf8ad359..a9b32722b049 100644
> --- a/drivers/tty/serial/mxs-auart.c
> +++ b/drivers/tty/serial/mxs-auart.c
> @@ -1595,7 +1595,7 @@ static int mxs_auart_probe(struct platform_device *pdev)
> return -EINVAL;
> }
>
> - s->devtype = (enum mxs_auart_type)of_device_get_match_data(&pdev->dev);
> + s->devtype = (uintptr_t)of_device_get_match_data(&pdev->dev);

This feels like a compiler issue as devtype is a enum mxs_auart_type
variable, so the cast shoudl be correct.

And if not, unitptr_t isn't a valid kernel type, so that's not a good
solution either. Worst case, it's how big a pointer is, which is not
going to be what an enum is if you have a sane compiler :(

thanks,

greg k-h