[PATCH v2 06/25] rust: platform: implement Sync for Device<Bound>

[Danilo Krummrich]

Device<Bound> uses the same underlying struct platform_device as
Device<Normal>; Bound is a zero-sized type-state marker that does not
affect thread safety.

This is needed for drivers to store &'bound platform::Device<Bound> in
their HRT private data while remaining Send.

Signed-off-by: Danilo Krummrich <dakr@xxxxxxxxxx>
---
 rust/kernel/platform.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index 506731a648c2..aec26307ae68 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -564,3 +564,7 @@ unsafe impl Send for Device {}
 // SAFETY: `Device` can be shared among threads because all methods of `Device`
 // (i.e. `Device<Normal>) are thread safe.
 unsafe impl Sync for Device {}
+
+// SAFETY: Same as `Device<Normal>` -- the underlying `struct platform_device` is the same;
+// `Bound` is a zero-sized type-state marker that does not affect thread safety.
+unsafe impl Sync for Device<device::Bound> {}
-- 
2.54.0