A future Clippy warning, `clippy::as_underscore`, is getting enabled in
parallel in the rust-next tree:

    error: using `as _` conversion
      --> rust/kernel/acpi.rs:25:9
       |
    25 |         self.0.driver_data as _
       |         ^^^^^^^^^^^^^^^^^^^^^^-
       |                               |
       |                               help: consider giving the type explicitly: `usize`

The type is already `ulong`, which nowadays is always `usize`, so the
cast is unneeded. Thus remove it, which in turn will avoid the warning
in the future.

Other abstractions of device tables do not use a cast here either.

Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
I noticed this in -next -- please feel free to rebase if preferred.

 rust/kernel/acpi.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rust/kernel/acpi.rs b/rust/kernel/acpi.rs
index eaae3bc8e54c..2af4d4f92924 100644
--- a/rust/kernel/acpi.rs
+++ b/rust/kernel/acpi.rs
@@ -22,7 +22,7 @@ unsafe impl RawDeviceId for DeviceId {
     const DRIVER_DATA_OFFSET: usize = core::mem::offset_of!(bindings::acpi_device_id, driver_data);

     fn index(&self) -> usize {
-        self.0.driver_data as _
+        self.0.driver_data
     }
 }


base-commit: f5d3ef25d238901a76fe0277787afa44f7714739
--
2.50.0

On Tue, Jul 1, 2025 at 7:48 PM Miguel Ojeda <ojeda@kernel.org> wrote:
>
> A future Clippy warning, `clippy::as_underscore`, is getting enabled in
> parallel in the rust-next tree:
>
>     error: using `as _` conversion
>       --> rust/kernel/acpi.rs:25:9
>        |
>     25 |         self.0.driver_data as _
>        |         ^^^^^^^^^^^^^^^^^^^^^^-
>        |                               |
>        |                               help: consider giving the type explicitly: `usize`
>
> The type is already `ulong`, which nowadays is always `usize`, so the
> cast is unneeded. Thus remove it, which in turn will avoid the warning
> in the future.
>
> Other abstractions of device tables do not use a cast here either.
>
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Alice Ryhl <aliceryhl@google.com>

On Tue Jul 1, 2025 at 12:46 PM CDT, Miguel Ojeda wrote:
> A future Clippy warning, `clippy::as_underscore`, is getting enabled in
> parallel in the rust-next tree:
>
>     error: using `as _` conversion
>       --> rust/kernel/acpi.rs:25:9
>        |
>     25 |         self.0.driver_data as _
>        |         ^^^^^^^^^^^^^^^^^^^^^^-
>        |                               |
>        |                               help: consider giving the type explicitly: `usize`
>
> The type is already `ulong`, which nowadays is always `usize`, so the
> cast is unneeded. Thus remove it, which in turn will avoid the warning
> in the future.
>
> Other abstractions of device tables do not use a cast here either.
>
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Trevor Gross <tmgross@umich.edu>