1 files changed, 33 insertions, 15 deletions

diff --git a/rust/kernel/usb.rs b/rust/kernel/usb.rs
index d10b65e9fb6a..0e1b9a88f4f1 100644
--- a/rust/kernel/usb.rs
+++ b/rust/kernel/usb.rs
@@ -6,14 +6,23 @@
 //! C header: [`include/linux/usb.h`](srctree/include/linux/usb.h)
 
 use crate::{
-    bindings, device,
-    device_id::{RawDeviceId, RawDeviceIdIndex},
+    bindings,
+    device,
+    device_id::{
+        RawDeviceId,
+        RawDeviceIdIndex, //
+    },
     driver,
-    error::{from_result, to_result, Result},
+    error::{
+        from_result,
+        to_result, //
+    },
     prelude::*,
-    str::CStr,
-    types::{AlwaysRefCounted, Opaque},
-    ThisModule,
+    types::{
+        AlwaysRefCounted,
+        Opaque, //
+    },
+    ThisModule, //
 };
 use core::{
     marker::PhantomData,
@@ -27,13 +36,22 @@ use core::{
 /// An adapter for the registration of USB drivers.
 pub struct Adapter<T: Driver>(T);
 
-// SAFETY: A call to `unregister` for a given instance of `RegType` is guaranteed to be valid if
+// SAFETY:
+// - `bindings::usb_driver` is a C type declared as `repr(C)`.
+// - `T` is the type of the driver's device private data.
+// - `struct usb_driver` embeds a `struct device_driver`.
+// - `DEVICE_DRIVER_OFFSET` is the correct byte offset to the embedded `struct device_driver`.
+unsafe impl<T: Driver + 'static> driver::DriverLayout for Adapter<T> {
+    type DriverType = bindings::usb_driver;
+    type DriverData = T;
+    const DEVICE_DRIVER_OFFSET: usize = core::mem::offset_of!(Self::DriverType, driver);
+}
+
+// SAFETY: A call to `unregister` for a given instance of `DriverType` is guaranteed to be valid if
 // a preceding call to `register` has been successful.
 unsafe impl<T: Driver + 'static> driver::RegistrationOps for Adapter<T> {
-    type RegType = bindings::usb_driver;
-
     unsafe fn register(
-        udrv: &Opaque<Self::RegType>,
+        udrv: &Opaque<Self::DriverType>,
         name: &'static CStr,
         module: &'static ThisModule,
     ) -> Result {
@@ -45,14 +63,14 @@ unsafe impl<T: Driver + 'static> driver::RegistrationOps for Adapter<T> {
             (*udrv.get()).id_table = T::ID_TABLE.as_ptr();
         }
 
-        // SAFETY: `udrv` is guaranteed to be a valid `RegType`.
+        // SAFETY: `udrv` is guaranteed to be a valid `DriverType`.
         to_result(unsafe {
             bindings::usb_register_driver(udrv.get(), module.0, name.as_char_ptr())
         })
     }
 
-    unsafe fn unregister(udrv: &Opaque<Self::RegType>) {
-        // SAFETY: `udrv` is guaranteed to be a valid `RegType`.
+    unsafe fn unregister(udrv: &Opaque<Self::DriverType>) {
+        // SAFETY: `udrv` is guaranteed to be a valid `DriverType`.
         unsafe { bindings::usb_deregister(udrv.get()) };
     }
 }
@@ -94,9 +112,9 @@ impl<T: Driver + 'static> Adapter<T> {
         // SAFETY: `disconnect_callback` is only ever called after a successful call to
         // `probe_callback`, hence it's guaranteed that `Device::set_drvdata()` has been called
         // and stored a `Pin<KBox<T>>`.
-        let data = unsafe { dev.drvdata_obtain::<T>() };
+        let data = unsafe { dev.drvdata_borrow::<T>() };
 
-        T::disconnect(intf, data.as_ref());
+        T::disconnect(intf, data);
     }
 }