Re: [PATCH 2/2] rust: pci: display symbolic PCI vendor names

[John Hubbard]

On 9/24/25 6:33 PM, John Hubbard wrote:
> The Display implementation for Vendor was forwarding directly to Debug
> printing, resulting in raw hex values instead of PCI Vendor strings.
> 
> Improve things by doing a stringify!() call for each PCI Vendor item.
> This now prints symbolic names such as "NVIDIA", instead of
> "Vendor(0x10de)". It still falls back to Debug formatting for unknown
> class values.
> 
> Suggested-by: Danilo Krummrich <dakr@xxxxxxxxxx>
> Signed-off-by: John Hubbard <jhubbard@xxxxxxxxxx>
> ---
>  rust/kernel/pci/id.rs | 19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/rust/kernel/pci/id.rs b/rust/kernel/pci/id.rs
> index 6e081de30faf..63db4d5f5617 100644
> --- a/rust/kernel/pci/id.rs
> +++ b/rust/kernel/pci/id.rs
> @@ -135,6 +135,18 @@ impl Vendor {
>                  pub const $variant: Self = Self($binding as u16);
>              )+
>          }
> +
> +        impl fmt::Display for Vendor {
> +            #[inline]

That #[inline] snuck in somehow (it's not in Class), but it should
not be there, because this expands to many lines of implementation.

If there is a v2 I'll remove it, otherwise maybe we can just ask
the maintainer to snip out that line.

thanks,
John Hubbard

> +            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
> +                match self {
> +                    $(
> +                        &Self::$variant => write!(f, stringify!($variant)),
> +                    )+
> +                    _ => <Self as fmt::Debug>::fmt(self, f),
> +                }
> +            }
> +        }
>      };
>  }
>  
> @@ -160,13 +172,6 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
>      }
>  }
>  
> -impl fmt::Display for Vendor {
> -    #[inline]
> -    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
> -        <Self as fmt::Debug>::fmt(self, f)
> -    }
> -}
> -
>  define_all_pci_classes! {
>      NOT_DEFINED                = bindings::PCI_CLASS_NOT_DEFINED,                // 0x000000
>      NOT_DEFINED_VGA            = bindings::PCI_CLASS_NOT_DEFINED_VGA,            // 0x000100