[PATCH 6/8] rust: auxiliary: implement parent() for Device

Danilo Krummrich
2025-10-20T22:36:01Z

Take advantage of the fact that if the auxiliary device is bound the
parent is guaranteed to be bound as well and implement a separate
parent() method for auxiliary::Device<Bound>.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---
rust/kernel/auxiliary.rs | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/rust/kernel/auxiliary.rs b/rust/kernel/auxiliary.rs
index 497601f7473b..cc67fa5ddde3 100644
--- a/rust/kernel/auxiliary.rs
+++ b/rust/kernel/auxiliary.rs
@@ -217,6 +217,16 @@ pub fn id(&self) -> u32 {
}
}

+impl Device<device::Bound> {
+ /// Returns a bound reference to the parent [`device::Device`].
+ pub fn parent(&self) -> &device::Device<device::Bound> {
+ let parent = (**self).parent();
+
+ // SAFETY: A bound auxiliary device always has a bound parent device.
+ unsafe { parent.as_bound() }
+ }
+}
+
impl Device {
/// Returns a reference to the parent [`device::Device`].
pub fn parent(&self) -> &device::Device {
--
2.51.0