Re: [PATCH] rust: prelude: add bit function

[Carlos Bilbao]

On 1/30/24 13:47, Christina Quast wrote:
> In order to create masks easily, the define BIT() is used in C code.
> This commit adds the same functionality to the rust kernel.
>
> To use it, include the following into your rust file:
> use kernel::prelude::bit
>
> Signed-off-by: Christina Quast <contact@xxxxxxxxxxxxxxxxxx>

Reviewed-by: Carlos Bilbao <carlos.bilbao@xxxxxxx>

> ---
> This patch is needed for further patches porting the rockchip phy
> driver to rust.
> ---
>   rust/kernel/prelude.rs | 16 ++++++++++++++++
>   1 file changed, 16 insertions(+)
>
> diff --git a/rust/kernel/prelude.rs b/rust/kernel/prelude.rs
> index ae21600970b3..16e483de2f27 100644
> --- a/rust/kernel/prelude.rs
> +++ b/rust/kernel/prelude.rs
> @@ -38,3 +38,19 @@
>   pub use super::init::{InPlaceInit, Init, PinInit};
>   
>   pub use super::current;
> +
> +/// Returns a `u32` number that has only the `n`th bit set.
> +///
> +/// # Arguments
> +///
> +/// * `n` - A `u32` that specifies the bit position (zero-based index)
> +///
> +/// # Example
> +///
> +/// ```
> +/// let b = bit(2);
> +/// assert_eq!(b, 4);
> +#[inline]
> +pub const fn bit(n: u32) -> u32 {
> +    1 << n
> +}
>
> ---
> base-commit: 6613476e225e090cc9aad49be7fa504e290dd33d
> change-id: 20240130-rust-bit-99dd6d3a0536
>
> Best regards,