rust: io_mem: Add helper to construct a Resource from bindings:resource

This will be used in multiple code paths later.

Signed-off-by: Asahi Lina <lina@asahilina.net>

Author: hoshinolina

rust/kernel/io_mem.rs

@@ -37,6 +37,10 @@ impl Resource {
             flags,
         })
     }
+
+    pub(crate) fn new_from_resource(res: &bindings::resource) -> Option<Self> {
+        Self::new(res.start, res.end, res.flags)
+    }
 }
 
 /// Represents a memory block of at least `SIZE` bytes.

rust/kernel/platform.rs

@@ -251,7 +251,7 @@ impl Device {
 
         // SAFETY: The pointer `res` is returned from `bindings::platform_get_resource`
         // above and checked if it is not a NULL.
-        unsafe { Resource::new((*res).start, (*res).end, (*res).flags) }.ok_or(EINVAL)
+        Resource::new_from_resource(unsafe { &*res }).ok_or(EINVAL)
     }
 
     /// Ioremaps resources of a platform device.