From: Danilo Krummrich <dakr@kernel.org>
Date: Mon, 20 Oct 2025 22:34:28 +0000 (+0200)
Subject: rust: auxiliary: implement parent() for Device<Bound>
X-Git-Tag: v6.19-rc1~90^2~56
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=675e514edd659b5cfc15eb70bd8abf53568947cc;p=thirdparty%2Fkernel%2Flinux.git

rust: auxiliary: implement parent() for Device<Bound>

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>.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---

diff --git a/rust/kernel/auxiliary.rs b/rust/kernel/auxiliary.rs
index 497601f7473bf..cc67fa5ddde30 100644
--- a/rust/kernel/auxiliary.rs
+++ b/rust/kernel/auxiliary.rs
@@ -217,6 +217,16 @@ impl<Ctx: device::DeviceContext> Device<Ctx> {
     }
 }
 
+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 {