From cb271c2edfd0ab7204d5ef3c9d5ae9a0710f5bf2 Mon Sep 17 00:00:00 2001
From: Danilo Krummrich <dakr@kernel.org>
Date: Sun, 13 Apr 2025 19:36:56 +0200
Subject: rust: device: implement impl_device_context_deref!

The Deref hierarchy for device context generics is the same for every
(bus specific) device.

Implement those with a generic macro to avoid duplicated boiler plate
code and ensure the correct Deref hierarchy for every device
implementation.

Co-developed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Link: https://lore.kernel.org/r/20250413173758.12068-2-dakr@kernel.org
[ Add missing `::` prefix in macros. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---
 rust/kernel/platform.rs | 17 +++--------------
 1 file changed, 3 insertions(+), 14 deletions(-)

(limited to 'rust/kernel/platform.rs')

diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index 4917cb34e2fe..22590bdff7bb 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -16,7 +16,6 @@ use crate::{
 
 use core::{
     marker::PhantomData,
-    ops::Deref,
     ptr::{addr_of_mut, NonNull},
 };
 
@@ -190,19 +189,9 @@ impl Device {
     }
 }
 
-impl Deref for Device<device::Core> {
-    type Target = Device;
-
-    fn deref(&self) -> &Self::Target {
-        let ptr: *const Self = self;
-
-        // CAST: `Device<Ctx>` is a transparent wrapper of `Opaque<bindings::platform_device>`.
-        let ptr = ptr.cast::<Device>();
-
-        // SAFETY: `ptr` was derived from `&self`.
-        unsafe { &*ptr }
-    }
-}
+// SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic
+// argument.
+kernel::impl_device_context_deref!(unsafe { Device });
 
 impl From<&Device<device::Core>> for ARef<Device> {
     fn from(dev: &Device<device::Core>) -> Self {
-- 
cgit v1.2.3


From fbb92b6a534081cabd75861ac9c7a8d29d8effda Mon Sep 17 00:00:00 2001
From: Danilo Krummrich <dakr@kernel.org>
Date: Sun, 13 Apr 2025 19:36:57 +0200
Subject: rust: device: implement impl_device_context_into_aref!

Implement a macro to implement all From conversions of a certain device
to ARef<Device>.

This avoids unnecessary boiler plate code for every device
implementation.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-3-dakr@kernel.org
[ Add missing `::` prefix in macros. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---
 rust/kernel/platform.rs | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

(limited to 'rust/kernel/platform.rs')

diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index 22590bdff7bb..9476b717c425 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -10,7 +10,7 @@ use crate::{
     of,
     prelude::*,
     str::CStr,
-    types::{ARef, ForeignOwnable, Opaque},
+    types::{ForeignOwnable, Opaque},
     ThisModule,
 };
 
@@ -192,12 +192,7 @@ impl Device {
 // SAFETY: `Device` is a transparent wrapper of a type that doesn't depend on `Device`'s generic
 // argument.
 kernel::impl_device_context_deref!(unsafe { Device });
-
-impl From<&Device<device::Core>> for ARef<Device> {
-    fn from(dev: &Device<device::Core>) -> Self {
-        (&**dev).into()
-    }
-}
+kernel::impl_device_context_into_aref!(Device);
 
 // SAFETY: Instances of `Device` are always reference-counted.
 unsafe impl crate::types::AlwaysRefCounted for Device {
-- 
cgit v1.2.3


From da6c47c6cb45ffb392e016631c08098ad2a6d418 Mon Sep 17 00:00:00 2001
From: Danilo Krummrich <dakr@kernel.org>
Date: Sun, 13 Apr 2025 19:36:59 +0200
Subject: rust: platform: preserve device context in AsRef

Since device::Device has a generic over its context, preserve this
device context in AsRef.

For instance, when calling platform::Device<Core> the new AsRef
implementation returns device::Device<Core>.

Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20250413173758.12068-5-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
---
 rust/kernel/platform.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

(limited to 'rust/kernel/platform.rs')

diff --git a/rust/kernel/platform.rs b/rust/kernel/platform.rs
index 9476b717c425..b1c48cd95cd6 100644
--- a/rust/kernel/platform.rs
+++ b/rust/kernel/platform.rs
@@ -183,7 +183,7 @@ pub struct Device<Ctx: device::DeviceContext = device::Normal>(
     PhantomData<Ctx>,
 );
 
-impl Device {
+impl<Ctx: device::DeviceContext> Device<Ctx> {
     fn as_raw(&self) -> *mut bindings::platform_device {
         self.0.get()
     }
@@ -207,8 +207,8 @@ unsafe impl crate::types::AlwaysRefCounted for Device {
     }
 }
 
-impl AsRef<device::Device> for Device {
-    fn as_ref(&self) -> &device::Device {
+impl<Ctx: device::DeviceContext> AsRef<device::Device<Ctx>> for Device<Ctx> {
+    fn as_ref(&self) -> &device::Device<Ctx> {
         // SAFETY: By the type invariant of `Self`, `self.as_raw()` is a pointer to a valid
         // `struct platform_device`.
         let dev = unsafe { addr_of_mut!((*self.as_raw()).dev) };
-- 
cgit v1.2.3