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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
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Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
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+[![Crates.io](https://img.shields.io/crates/v/pin-init.svg)](https://crates.io/crates/pin-init)
+[![Documentation](https://docs.rs/pin-init/badge.svg)](https://docs.rs/pin-init/)
+[![Dependency status](https://deps.rs/repo/github/Rust-for-Linux/pin-init/status.svg)](https://deps.rs/repo/github/Rust-for-Linux/pin-init)
+![License](https://img.shields.io/crates/l/pin-init)
+[![Toolchain](https://img.shields.io/badge/toolchain-nightly-red)](#nightly-only)
+![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/Rust-for-Linux/pin-init/ci.yml)
+# `pin-init`
+
+> [!NOTE]
+>
+> This crate was originally named [`pinned-init`], but the migration to
+> `pin-init` is not yet complete. The `legacy` branch contains the current
+> version of the `pinned-init` crate & the `main` branch already incorporates
+> the rename to `pin-init`.
+>
+> There are still some changes needed on the kernel side before the migration
+> can be completed.
+
+[`pinned-init`]: https://crates.io/crates/pinned-init
+
+<!-- cargo-rdme start -->
+
+Library to safely and fallibly initialize pinned `struct`s using in-place constructors.
+
+[Pinning][pinning] is Rust's way of ensuring data does not move.
+
+It also allows in-place initialization of big `struct`s that would otherwise produce a stack
+overflow.
+
+This library's main use-case is in [Rust-for-Linux]. Although this version can be used
+standalone.
+
+There are cases when you want to in-place initialize a struct. For example when it is very big
+and moving it from the stack is not an option, because it is bigger than the stack itself.
+Another reason would be that you need the address of the object to initialize it. This stands
+in direct conflict with Rust's normal process of first initializing an object and then moving
+it into it's final memory location. For more information, see
+<https://rust-for-linux.com/the-safe-pinned-initialization-problem>.
+
+This library allows you to do in-place initialization safely.
+
+### Nightly Needed for `alloc` feature
+
+This library requires the [`allocator_api` unstable feature] when the `alloc` feature is
+enabled and thus this feature can only be used with a nightly compiler. When enabling the
+`alloc` feature, the user will be required to activate `allocator_api` as well.
+
+[`allocator_api` unstable feature]: https://doc.rust-lang.org/nightly/unstable-book/library-features/allocator-api.html
+
+The feature is enabled by default, thus by default `pin-init` will require a nightly compiler.
+However, using the crate on stable compilers is possible by disabling `alloc`. In practice this
+will require the `std` feature, because stable compilers have neither `Box` nor `Arc` in no-std
+mode.
+
+### Nightly needed for `unsafe-pinned` feature
+
+This feature enables the `Wrapper` implementation on the unstable `core::pin::UnsafePinned` type.
+This requires the [`unsafe_pinned` unstable feature](https://github.com/rust-lang/rust/issues/125735)
+and therefore a nightly compiler. Note that this feature is not enabled by default.
+
+## Overview
+
+To initialize a `struct` with an in-place constructor you will need two things:
+- an in-place constructor,
+- a memory location that can hold your `struct` (this can be the [stack], an [`Arc<T>`],
+ [`Box<T>`] or any other smart pointer that supports this library).
+
+To get an in-place constructor there are generally three options:
+- directly creating an in-place constructor using the [`pin_init!`] macro,
+- a custom function/macro returning an in-place constructor provided by someone else,
+- using the unsafe function [`pin_init_from_closure()`] to manually create an initializer.
+
+Aside from pinned initialization, this library also supports in-place construction without
+pinning, the macros/types/functions are generally named like the pinned variants without the
+`pin_` prefix.
+
+## Examples
+
+Throughout the examples we will often make use of the `CMutex` type which can be found in
+`../examples/mutex.rs`. It is essentially a userland rebuild of the `struct mutex` type from
+the Linux kernel. It also uses a wait list and a basic spinlock. Importantly the wait list
+requires it to be pinned to be locked and thus is a prime candidate for using this library.
+
+### Using the [`pin_init!`] macro
+
+If you want to use [`PinInit`], then you will have to annotate your `struct` with
+`#[`[`pin_data`]`]`. It is a macro that uses `#[pin]` as a marker for
+[structurally pinned fields]. After doing this, you can then create an in-place constructor via
+[`pin_init!`]. The syntax is almost the same as normal `struct` initializers. The difference is
+that you need to write `<-` instead of `:` for fields that you want to initialize in-place.
+
+```rust
+use pin_init::{pin_data, pin_init, InPlaceInit};
+
+#[pin_data]
+struct Foo {
+ #[pin]
+ a: CMutex<usize>,
+ b: u32,
+}
+
+let foo = pin_init!(Foo {
+ a <- CMutex::new(42),
+ b: 24,
+});
+```
+
+`foo` now is of the type [`impl PinInit<Foo>`]. We can now use any smart pointer that we like
+(or just the stack) to actually initialize a `Foo`:
+
+```rust
+let foo: Result<Pin<Box<Foo>>, AllocError> = Box::pin_init(foo);
+```
+
+For more information see the [`pin_init!`] macro.
+
+### Using a custom function/macro that returns an initializer
+
+Many types that use this library supply a function/macro that returns an initializer, because
+the above method only works for types where you can access the fields.
+
+```rust
+let mtx: Result<Pin<Arc<CMutex<usize>>>, _> = Arc::pin_init(CMutex::new(42));
+```
+
+To declare an init macro/function you just return an [`impl PinInit<T, E>`]:
+
+```rust
+#[pin_data]
+struct DriverData {
+ #[pin]
+ status: CMutex<i32>,
+ buffer: Box<[u8; 1_000_000]>,
+}
+
+impl DriverData {
+ fn new() -> impl PinInit<Self, Error> {
+ pin_init!(Self {
+ status <- CMutex::new(0),
+ buffer: Box::init(pin_init::init_zeroed())?,
+ }? Error)
+ }
+}
+```
+
+### Manual creation of an initializer
+
+Often when working with primitives the previous approaches are not sufficient. That is where
+[`pin_init_from_closure()`] comes in. This `unsafe` function allows you to create a
+[`impl PinInit<T, E>`] directly from a closure. Of course you have to ensure that the closure
+actually does the initialization in the correct way. Here are the things to look out for
+(we are calling the parameter to the closure `slot`):
+- when the closure returns `Ok(())`, then it has completed the initialization successfully, so
+ `slot` now contains a valid bit pattern for the type `T`,
+- when the closure returns `Err(e)`, then the caller may deallocate the memory at `slot`, so
+ you need to take care to clean up anything if your initialization fails mid-way,
+- you may assume that `slot` will stay pinned even after the closure returns until `drop` of
+ `slot` gets called.
+
+```rust
+use pin_init::{pin_data, pinned_drop, PinInit, PinnedDrop, pin_init_from_closure};
+use core::{
+ marker::PhantomPinned,
+ cell::UnsafeCell,
+ pin::Pin,
+ mem::MaybeUninit,
+};
+mod bindings {
+ #[repr(C)]
+ pub struct foo {
+ /* fields from C ... */
+ }
+ extern "C" {
+ pub fn init_foo(ptr: *mut foo);
+ pub fn destroy_foo(ptr: *mut foo);
+ #[must_use = "you must check the error return code"]
+ pub fn enable_foo(ptr: *mut foo, flags: u32) -> i32;
+ }
+}
+
+/// # Invariants
+///
+/// `foo` is always initialized
+#[pin_data(PinnedDrop)]
+pub struct RawFoo {
+ #[pin]
+ _p: PhantomPinned,
+ #[pin]
+ foo: UnsafeCell<MaybeUninit<bindings::foo>>,
+}
+
+impl RawFoo {
+ pub fn new(flags: u32) -> impl PinInit<Self, i32> {
+ // SAFETY:
+ // - when the closure returns `Ok(())`, then it has successfully initialized and
+ // enabled `foo`,
+ // - when it returns `Err(e)`, then it has cleaned up before
+ unsafe {
+ pin_init_from_closure(move |slot: *mut Self| {
+ // `slot` contains uninit memory, avoid creating a reference.
+ let foo = &raw mut (*slot).foo;
+ let foo = UnsafeCell::raw_get(foo).cast::<bindings::foo>();
+
+ // Initialize the `foo`
+ bindings::init_foo(foo);
+
+ // Try to enable it.
+ let err = bindings::enable_foo(foo, flags);
+ if err != 0 {
+ // Enabling has failed, first clean up the foo and then return the error.
+ bindings::destroy_foo(foo);
+ Err(err)
+ } else {
+ // All fields of `RawFoo` have been initialized, since `_p` is a ZST.
+ Ok(())
+ }
+ })
+ }
+ }
+}
+
+#[pinned_drop]
+impl PinnedDrop for RawFoo {
+ fn drop(self: Pin<&mut Self>) {
+ // SAFETY: Since `foo` is initialized, destroying is safe.
+ unsafe { bindings::destroy_foo(self.foo.get().cast::<bindings::foo>()) };
+ }
+}
+```
+
+For more information on how to use [`pin_init_from_closure()`], take a look at the uses inside
+the `kernel` crate. The [`sync`] module is a good starting point.
+
+[`sync`]: https://rust.docs.kernel.org/kernel/sync/index.html
+[pinning]: https://doc.rust-lang.org/std/pin/index.html
+[structurally pinned fields]: https://doc.rust-lang.org/std/pin/index.html#projections-and-structural-pinning
+[stack]: https://docs.rs/pin-init/latest/pin_init/macro.stack_pin_init.html
+[`impl PinInit<Foo>`]: https://docs.rs/pin-init/latest/pin_init/trait.PinInit.html
+[`impl PinInit<T, E>`]: https://docs.rs/pin-init/latest/pin_init/trait.PinInit.html
+[`impl Init<T, E>`]: https://docs.rs/pin-init/latest/pin_init/trait.Init.html
+[Rust-for-Linux]: https://rust-for-linux.com/
+
+<!-- cargo-rdme end -->
+
+<!-- These links are not picked up by cargo-rdme, since they are behind cfgs... -->
+[`Arc<T>`]: https://doc.rust-lang.org/stable/alloc/sync/struct.Arc.html
+[`Box<T>`]: https://doc.rust-lang.org/stable/alloc/boxed/struct.Box.html