@@ -27,7 +27,7 @@
marker::*,
ptr::{NonNull, null, null_mut, addr_of_mut, self},
ops::{Deref, DerefMut},
- mem,
+ mem::{self, ManuallyDrop},
};
use macros::vtable;
@@ -82,7 +82,7 @@ pub trait DriverCrtc: Send + Sync + Sized {
helper_funcs: bindings::drm_crtc_helper_funcs {
atomic_disable: None,
atomic_enable: None,
- atomic_check: None,
+ atomic_check: if Self::HAS_ATOMIC_CHECK { Some(atomic_check_callback::<Self>) } else { None },
dpms: None,
commit: None,
prepare: None,
@@ -117,6 +117,21 @@ pub trait DriverCrtc: Send + Sync + Sized {
///
/// Drivers may use this to instantiate their [`DriverCrtc`] object.
fn new(device: &Device<Self::Driver>, args: &Self::Args) -> impl PinInit<Self, Error>;
+
+ /// The optional [`drm_crtc_helper_funcs.atomic_check`] hook for this crtc.
+ ///
+ /// Drivers may use this to customize the atomic check phase of their [`Crtc`] objects. The
+ /// result of this function determines whether the atomic check passed or failed.
+ ///
+ /// [`drm_crtc_helper_funcs.atomic_check`]: srctree/include/drm/drm_modeset_helper_vtables.h
+ fn atomic_check(
+ crtc: &Crtc<Self>,
+ old_state: &CrtcState<Self::State>,
+ new_state: BorrowedCrtcState<'_, CrtcState<Self::State>>,
+ state: &AtomicStateComposer<Self::Driver>
+ ) -> Result {
+ build_error::build_error("This should not be reachable")
+ }
}
/// The generated C vtable for a [`DriverCrtc`].
@@ -726,3 +741,30 @@ fn as_raw(&self) -> *mut bindings::drm_crtc_state {
)
};
}
+
+unsafe extern "C" fn atomic_check_callback<T: DriverCrtc>(
+ crtc: *mut bindings::drm_crtc,
+ state: *mut bindings::drm_atomic_state,
+) -> i32 {
+ // SAFETY:
+ // * We're guaranteed `crtc` is of type `Crtc<T>` via type invariants.
+ // * We're guaranteed by DRM that `crtc` is pointing to a valid initialized state.
+ let crtc = unsafe { Crtc::from_raw(crtc) };
+
+ // SAFETY: DRM guarantees `state` points to a valid `drm_atomic_state`
+ let state = unsafe {
+ ManuallyDrop::new(AtomicStateComposer::new(NonNull::new_unchecked(state)))
+ };
+
+ // SAFETY: Since we are in the atomic update callback, we're guaranteed by DRM that both the old
+ // and new atomic state are present within `state`
+ let (old_state, new_state) = unsafe {(
+ state.get_old_crtc_state(crtc).unwrap_unchecked(),
+ state.get_new_crtc_state(crtc).unwrap_unchecked(),
+ )};
+
+ from_result(|| {
+ T::atomic_check(crtc, old_state, new_state, &state)?;
+ Ok(0)
+ })
+}
An optional trait method for implementing a CRTC's atomic state check. Signed-off-by: Lyude Paul <lyude@redhat.com> --- rust/kernel/drm/kms/crtc.rs | 46 +++++++++++++++++++++++++++++++++++-- 1 file changed, 44 insertions(+), 2 deletions(-)