[WIP RFC v2 17/35] rust: drm/kms: Add RawCrtc and RawCrtcState

[Daniel Almeida]

Hi Lyude,

> On 30 Sep 2024, at 20:10, Lyude Paul <lyude at redhat.com> wrote:
> 
> Same thing as RawConnector and RawConnectorState, just for CRTCs now.
> 
> Signed-off-by: Lyude Paul <lyude at redhat.com>
> ---
> rust/kernel/drm/kms/crtc.rs | 25 +++++++++++++++++++++++--
> 1 file changed, 23 insertions(+), 2 deletions(-)
> 
> diff --git a/rust/kernel/drm/kms/crtc.rs b/rust/kernel/drm/kms/crtc.rs
> index 1a3c9c448afcc..246d15a15c14d 100644
> --- a/rust/kernel/drm/kms/crtc.rs
> +++ b/rust/kernel/drm/kms/crtc.rs
> @@ -302,6 +302,25 @@ unsafe fn from_raw<'a>(ptr: *mut bindings::drm_crtc) -> &'a Self {
>     }
> }
> 
> +/// Common methods available on any type which implements [`AsRawCrtc`].
> +///
> +/// This is implemented internally by DRM, and provides many of the basic methods for working with
> +/// CRTCs.
> +pub trait RawCrtc: AsRawCrtc {
> +    /// Return the index of this CRTC.
> +    fn index(&self) -> u32 {
> +        // SAFETY: The index is initialized by the time we expose Crtc objects to users, and is
> +        // invariant throughout the lifetime of the Crtc
> +        unsafe { (*self.as_raw()).index }
> +    }
> +
> +    /// Return the index of this DRM CRTC in the form of a bitmask.
> +    fn mask(&self) -> u32 {
> +        1 << self.index()
> +    }
> +}
> +impl<T: AsRawCrtc> RawCrtc for T {}
> +
> /// A [`struct drm_crtc`] without a known [`DriverCrtc`] implementation.
> ///
> /// This is mainly for situations where our bindings can't infer the [`DriverCrtc`] implementation
> @@ -447,8 +466,10 @@ pub trait AsRawCrtcState {
> 
> pub(super) use private::AsRawCrtcState as AsRawCrtcStatePrivate;
> 
> -/// A trait for providing common methods which can be used on any type that can be used as an atomic
> -/// CRTC state.
> +/// Common methods available on any type which implements [`AsRawCrtcState`].
> +///
> +/// This is implemented internally by DRM, and provides many of the basic methods for working with
> +/// the atomic state of [`Crtc`]s.
> pub trait RawCrtcState: AsRawCrtcState {
>     /// Return the CRTC that owns this state.
>     fn crtc(&self) -> &Self::Crtc {
> -- 
> 2.46.1

This also looks good.

— Daniel