[PATCH 3/7] rust: devres: support fallible in-place init for data

[Danilo Krummrich <dakr@kernel.org>]

Currently, Devres only supports a data argument of type T. However,
DevresInner already uses pin-init to initialize the Revocable. Hence,
there is no need for this limitation and we can take a data argument of
type impl PinInit<T, E> instead.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---
 rust/kernel/devres.rs | 27 ++++++++++++++++++++++-----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/rust/kernel/devres.rs b/rust/kernel/devres.rs
index 2dbe17d6ea1f..47aeb5196dd2 100644
--- a/rust/kernel/devres.rs
+++ b/rust/kernel/devres.rs
@@ -96,9 +96,16 @@ struct DevresInner<T> {
 pub struct Devres<T>(Arc<DevresInner<T>>);
 
 impl<T> DevresInner<T> {
-    fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Arc<DevresInner<T>>> {
-        let inner = Arc::pin_init(
-            try_pin_init!( DevresInner {
+    fn new<E>(
+        dev: &Device<Bound>,
+        data: impl PinInit<T, E>,
+        flags: Flags,
+    ) -> Result<Arc<DevresInner<T>>>
+    where
+        Error: From<E>,
+    {
+        let inner = Arc::pin_init::<Error>(
+            try_pin_init!( Self {
                 dev: dev.into(),
                 callback: Self::devres_callback,
                 data <- Revocable::new(data),
@@ -168,7 +175,10 @@ fn remove_action(this: &Arc<Self>) {
 impl<T> Devres<T> {
     /// Creates a new [`Devres`] instance of the given `data`. The `data` encapsulated within the
     /// returned `Devres` instance' `data` will be revoked once the device is detached.
-    pub fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Self> {
+    pub fn new<E>(dev: &Device<Bound>, data: impl PinInit<T, E>, flags: Flags) -> Result<Self>
+    where
+        Error: From<E>,
+    {
         let inner = DevresInner::new(dev, data, flags)?;
 
         Ok(Devres(inner))
@@ -176,7 +186,14 @@ pub fn new(dev: &Device<Bound>, data: T, flags: Flags) -> Result<Self> {
 
     /// Same as [`Devres::new`], but does not return a `Devres` instance. Instead the given `data`
     /// is owned by devres and will be revoked / dropped, once the device is detached.
-    pub fn new_foreign_owned(dev: &Device<Bound>, data: T, flags: Flags) -> Result {
+    pub fn new_foreign_owned<E>(
+        dev: &Device<Bound>,
+        data: impl PinInit<T, E>,
+        flags: Flags,
+    ) -> Result
+    where
+        Error: From<E>,
+    {
         let _ = DevresInner::new(dev, data, flags)?;
 
         Ok(())
-- 
2.49.0