[WIP RFC v2 25/35] rust: drm/kms: Add RawPlaneState::crtc()

[Daniel Almeida]

Hi Lyude

> On 30 Sep 2024, at 20:10, Lyude Paul <lyude at redhat.com> wrote:
> 
> Add a binding for checking drm_plane_state.crtc. Note that we don't have a
> way of knowing what DriverCrtc implementation would be used here (and want
> to make this function also available on OpaquePlaneState types), so we
> return an OpaqueCrtc.
> 
> Signed-off-by: Lyude Paul <lyude at redhat.com>
> ---
> rust/kernel/drm/kms/plane.rs | 7 +++++++
> 1 file changed, 7 insertions(+)
> 
> diff --git a/rust/kernel/drm/kms/plane.rs b/rust/kernel/drm/kms/plane.rs
> index 04f1bdfbb1ea2..4d16d53179fca 100644
> --- a/rust/kernel/drm/kms/plane.rs
> +++ b/rust/kernel/drm/kms/plane.rs
> @@ -30,6 +30,7 @@
>     ModeObject,
>     StaticModeObject,
>     atomic::*,
> +    crtc::*,
> };
> 
> /// The main trait for implementing the [`struct drm_plane`] API for [`Plane`]
> @@ -489,6 +490,12 @@ fn plane(&self) -> &Self::Plane {
>         // invariant throughout the lifetime of the Plane
>         unsafe { Self::Plane::from_raw(self.as_raw().plane) }
>     }
> +
> +    /// Return the current [`OpaqueCrtc`] assigned to this plane, if there is one.
> +    fn crtc<'a, 'b: 'a>(&'a self) -> Option<&'b OpaqueCrtc<<Self::Plane as ModeObject>::Driver>> {
> +        // SAFETY: This cast is guaranteed safe by `OpaqueCrtc`s invariants.
> +        NonNull::new(self.as_raw().crtc).map(|c| unsafe { OpaqueCrtc::from_raw(c.as_ptr()) })
> +    }
> }
> impl<T: AsRawPlaneState + ?Sized> RawPlaneState for T {}
> 
> -- 
> 2.46.1
> 
> 

LGTM,

— Daniel