Merge tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc/IIO/whatever driver subsystem updates from Greg KH:
 "Here is the 'big and hairy' char/misc/iio and other small driver
  subsystem updates for 6.13-rc1.

  Loads of things in here, and even a fun merge conflict!

   - rust misc driver bindings and other rust changes to make misc
     drivers actually possible.

     I think this is the tipping point, expect to see way more rust
     drivers going forward now that these bindings are present. Next
     merge window hopefully we will have pci and platform drivers
     working, which will fully enable almost all driver subsystems to
     start accepting (or at least getting) rust drivers.

     This is the end result of a lot of work from a lot of people,
     congrats to all of them for getting this far, you've proved many of
     us wrong in the best way possible, working code :)

   - IIO driver updates, too many to list individually, that subsystem
     keeps growing and growing...

   - Interconnect driver updates

   - nvmem driver updates

   - pwm driver updates

   - platform_driver::remove() fixups, loads of them

   - counter driver updates

   - misc driver updates (keba?)

   - binder driver updates and fixes

   - loads of other small char/misc/etc driver updates and additions,
     full details in the shortlog.

  All of these have been in linux-next for a while, with no other
  reported issues other than that merge conflict"

* tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (401 commits)
  mei: vsc: Fix typo "maintstepping" -> "mainstepping"
  firmware: Switch back to struct platform_driver::remove()
  misc: isl29020: Fix the wrong format specifier
  scripts/tags.sh: Don't tag usages of DEFINE_MUTEX
  fpga: Switch back to struct platform_driver::remove()
  mei: vsc: Improve error logging in vsc_identify_silicon()
  mei: vsc: Do not re-enable interrupt from vsc_tp_reset()
  dt-bindings: spmi: qcom,x1e80100-spmi-pmic-arb: Add SAR2130P compatible
  dt-bindings: spmi: spmi-mtk-pmif: Add compatible for MT8188
  spmi: pmic-arb: fix return path in for_each_available_child_of_node()
  iio: Move __private marking before struct element priv in struct iio_dev
  docs: iio: ad7380: add adaq4370-4 and adaq4380-4
  iio: adc: ad7380: add support for adaq4370-4 and adaq4380-4
  iio: adc: ad7380: use local dev variable to shorten long lines
  iio: adc: ad7380: fix oversampling formula
  dt-bindings: iio: adc: ad7380: add adaq4370-4 and adaq4380-4 compatible parts
  bus: mhi: host: pci_generic: Use pcim_iomap_region() to request and map MHI BAR
  bus: mhi: host: Switch trace_mhi_gen_tre fields to native endian
  misc: atmel-ssc: Use of_property_present() for non-boolean properties
  misc: keba: Add hardware dependency
  ...

7 files changed, 629 insertions, 17 deletions

diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index 54bc8a8c5c88..5c4dfe22f41a 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -19,6 +19,7 @@
 #include <linux/jiffies.h>
 #include <linux/jump_label.h>
 #include <linux/mdio.h>
+#include <linux/miscdevice.h>
 #include <linux/phy.h>
 #include <linux/pid_namespace.h>
 #include <linux/poll.h>
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index c8199ee079ef..c926e0c2b852 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -8,7 +8,10 @@ use crate::{
     bindings,
     types::{ARef, Opaque},
 };
-use core::ptr;
+use core::{fmt, ptr};
+
+#[cfg(CONFIG_PRINTK)]
+use crate::c_str;
 
 /// A reference-counted device.
 ///
@@ -73,6 +76,110 @@ impl Device {
         // SAFETY: Guaranteed by the safety requirements of the function.
         unsafe { &*ptr.cast() }
     }
+
+    /// Prints an emergency-level message (level 0) prefixed with device information.
+    ///
+    /// More details are available from [`dev_emerg`].
+    ///
+    /// [`dev_emerg`]: crate::dev_emerg
+    pub fn pr_emerg(&self, args: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+        unsafe { self.printk(bindings::KERN_EMERG, args) };
+    }
+
+    /// Prints an alert-level message (level 1) prefixed with device information.
+    ///
+    /// More details are available from [`dev_alert`].
+    ///
+    /// [`dev_alert`]: crate::dev_alert
+    pub fn pr_alert(&self, args: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+        unsafe { self.printk(bindings::KERN_ALERT, args) };
+    }
+
+    /// Prints a critical-level message (level 2) prefixed with device information.
+    ///
+    /// More details are available from [`dev_crit`].
+    ///
+    /// [`dev_crit`]: crate::dev_crit
+    pub fn pr_crit(&self, args: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+        unsafe { self.printk(bindings::KERN_CRIT, args) };
+    }
+
+    /// Prints an error-level message (level 3) prefixed with device information.
+    ///
+    /// More details are available from [`dev_err`].
+    ///
+    /// [`dev_err`]: crate::dev_err
+    pub fn pr_err(&self, args: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+        unsafe { self.printk(bindings::KERN_ERR, args) };
+    }
+
+    /// Prints a warning-level message (level 4) prefixed with device information.
+    ///
+    /// More details are available from [`dev_warn`].
+    ///
+    /// [`dev_warn`]: crate::dev_warn
+    pub fn pr_warn(&self, args: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+        unsafe { self.printk(bindings::KERN_WARNING, args) };
+    }
+
+    /// Prints a notice-level message (level 5) prefixed with device information.
+    ///
+    /// More details are available from [`dev_notice`].
+    ///
+    /// [`dev_notice`]: crate::dev_notice
+    pub fn pr_notice(&self, args: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+        unsafe { self.printk(bindings::KERN_NOTICE, args) };
+    }
+
+    /// Prints an info-level message (level 6) prefixed with device information.
+    ///
+    /// More details are available from [`dev_info`].
+    ///
+    /// [`dev_info`]: crate::dev_info
+    pub fn pr_info(&self, args: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+        unsafe { self.printk(bindings::KERN_INFO, args) };
+    }
+
+    /// Prints a debug-level message (level 7) prefixed with device information.
+    ///
+    /// More details are available from [`dev_dbg`].
+    ///
+    /// [`dev_dbg`]: crate::dev_dbg
+    pub fn pr_dbg(&self, args: fmt::Arguments<'_>) {
+        if cfg!(debug_assertions) {
+            // SAFETY: `klevel` is null-terminated, uses one of the kernel constants.
+            unsafe { self.printk(bindings::KERN_DEBUG, args) };
+        }
+    }
+
+    /// Prints the provided message to the console.
+    ///
+    /// # Safety
+    ///
+    /// Callers must ensure that `klevel` is null-terminated; in particular, one of the
+    /// `KERN_*`constants, for example, `KERN_CRIT`, `KERN_ALERT`, etc.
+    #[cfg_attr(not(CONFIG_PRINTK), allow(unused_variables))]
+    unsafe fn printk(&self, klevel: &[u8], msg: fmt::Arguments<'_>) {
+        // SAFETY: `klevel` is null-terminated and one of the kernel constants. `self.as_raw`
+        // is valid because `self` is valid. The "%pA" format string expects a pointer to
+        // `fmt::Arguments`, which is what we're passing as the last argument.
+        #[cfg(CONFIG_PRINTK)]
+        unsafe {
+            bindings::_dev_printk(
+                klevel as *const _ as *const core::ffi::c_char,
+                self.as_raw(),
+                c_str!("%pA").as_char_ptr(),
+                &msg as *const _ as *const core::ffi::c_void,
+            )
+        };
+    }
 }
 
 // SAFETY: Instances of `Device` are always reference-counted.
@@ -94,3 +201,213 @@ unsafe impl Send for Device {}
 // SAFETY: `Device` can be shared among threads because all immutable methods are protected by the
 // synchronization in `struct device`.
 unsafe impl Sync for Device {}
+
+#[doc(hidden)]
+#[macro_export]
+macro_rules! dev_printk {
+    ($method:ident, $dev:expr, $($f:tt)*) => {
+        {
+            ($dev).$method(core::format_args!($($f)*));
+        }
+    }
+}
+
+/// Prints an emergency-level message (level 0) prefixed with device information.
+///
+/// This level should be used if the system is unusable.
+///
+/// Equivalent to the kernel's `dev_emerg` macro.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_emerg!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_emerg {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_emerg, $($f)*); }
+}
+
+/// Prints an alert-level message (level 1) prefixed with device information.
+///
+/// This level should be used if action must be taken immediately.
+///
+/// Equivalent to the kernel's `dev_alert` macro.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_alert!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_alert {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_alert, $($f)*); }
+}
+
+/// Prints a critical-level message (level 2) prefixed with device information.
+///
+/// This level should be used in critical conditions.
+///
+/// Equivalent to the kernel's `dev_crit` macro.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_crit!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_crit {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_crit, $($f)*); }
+}
+
+/// Prints an error-level message (level 3) prefixed with device information.
+///
+/// This level should be used in error conditions.
+///
+/// Equivalent to the kernel's `dev_err` macro.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_err!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_err {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_err, $($f)*); }
+}
+
+/// Prints a warning-level message (level 4) prefixed with device information.
+///
+/// This level should be used in warning conditions.
+///
+/// Equivalent to the kernel's `dev_warn` macro.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_warn!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_warn {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_warn, $($f)*); }
+}
+
+/// Prints a notice-level message (level 5) prefixed with device information.
+///
+/// This level should be used in normal but significant conditions.
+///
+/// Equivalent to the kernel's `dev_notice` macro.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_notice!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_notice {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_notice, $($f)*); }
+}
+
+/// Prints an info-level message (level 6) prefixed with device information.
+///
+/// This level should be used for informational messages.
+///
+/// Equivalent to the kernel's `dev_info` macro.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_info!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_info {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_info, $($f)*); }
+}
+
+/// Prints a debug-level message (level 7) prefixed with device information.
+///
+/// This level should be used for debug messages.
+///
+/// Equivalent to the kernel's `dev_dbg` macro, except that it doesn't support dynamic debug yet.
+///
+/// Mimics the interface of [`std::print!`]. More information about the syntax is available from
+/// [`core::fmt`] and `alloc::format!`.
+///
+/// [`std::print!`]: https://doc.rust-lang.org/std/macro.print.html
+///
+/// # Examples
+///
+/// ```
+/// # use kernel::device::Device;
+///
+/// fn example(dev: &Device) {
+///     dev_dbg!(dev, "hello {}\n", "there");
+/// }
+/// ```
+#[macro_export]
+macro_rules! dev_dbg {
+    ($($f:tt)*) => { $crate::dev_printk!(pr_dbg, $($f)*); }
+}
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 04dbee70d3e6..e1065a7551a3 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -45,6 +45,7 @@ pub mod jump_label;
 #[cfg(CONFIG_KUNIT)]
 pub mod kunit;
 pub mod list;
+pub mod miscdevice;
 #[cfg(CONFIG_NET)]
 pub mod net;
 pub mod page;
@@ -92,6 +93,29 @@ pub trait Module: Sized + Sync + Send {
     fn init(module: &'static ThisModule) -> error::Result<Self>;
 }
 
+/// A module that is pinned and initialised in-place.
+pub trait InPlaceModule: Sync + Send {
+    /// Creates an initialiser for the module.
+    ///
+    /// It is called when the module is loaded.
+    fn init(module: &'static ThisModule) -> impl init::PinInit<Self, error::Error>;
+}
+
+impl<T: Module> InPlaceModule for T {
+    fn init(module: &'static ThisModule) -> impl init::PinInit<Self, error::Error> {
+        let initer = move |slot: *mut Self| {
+            let m = <Self as Module>::init(module)?;
+
+            // SAFETY: `slot` is valid for write per the contract with `pin_init_from_closure`.
+            unsafe { slot.write(m) };
+            Ok(())
+        };
+
+        // SAFETY: On success, `initer` always fully initialises an instance of `Self`.
+        unsafe { init::pin_init_from_closure(initer) }
+    }
+}
+
 /// Equivalent to `THIS_MODULE` in the C API.
 ///
 /// C header: [`include/linux/init.h`](srctree/include/linux/init.h)
diff --git a/rust/kernel/miscdevice.rs b/rust/kernel/miscdevice.rs
new file mode 100644
index 000000000000..7e2a79b3ae26
--- /dev/null
+++ b/rust/kernel/miscdevice.rs
@@ -0,0 +1,256 @@
+// SPDX-License-Identifier: GPL-2.0
+
+// Copyright (C) 2024 Google LLC.
+
+//! Miscdevice support.
+//!
+//! C headers: [`include/linux/miscdevice.h`](srctree/include/linux/miscdevice.h).
+//!
+//! Reference: <https://www.kernel.org/doc/html/latest/driver-api/misc_devices.html>
+
+use crate::{
+    bindings,
+    error::{to_result, Error, Result, VTABLE_DEFAULT_ERROR},
+    prelude::*,
+    str::CStr,
+    types::{ForeignOwnable, Opaque},
+};
+use core::{
+    ffi::{c_int, c_long, c_uint, c_ulong},
+    marker::PhantomData,
+    mem::MaybeUninit,
+    pin::Pin,
+};
+
+/// Options for creating a misc device.
+#[derive(Copy, Clone)]
+pub struct MiscDeviceOptions {
+    /// The name of the miscdevice.
+    pub name: &'static CStr,
+}
+
+impl MiscDeviceOptions {
+    /// Create a raw `struct miscdev` ready for registration.
+    pub const fn into_raw<T: MiscDevice>(self) -> bindings::miscdevice {
+        // SAFETY: All zeros is valid for this C type.
+        let mut result: bindings::miscdevice = unsafe { MaybeUninit::zeroed().assume_init() };
+        result.minor = bindings::MISC_DYNAMIC_MINOR as _;
+        result.name = self.name.as_char_ptr();
+        result.fops = create_vtable::<T>();
+        result
+    }
+}
+
+/// A registration of a miscdevice.
+///
+/// # Invariants
+///
+/// `inner` is a registered misc device.
+#[repr(transparent)]
+#[pin_data(PinnedDrop)]
+pub struct MiscDeviceRegistration<T> {
+    #[pin]
+    inner: Opaque<bindings::miscdevice>,
+    _t: PhantomData<T>,
+}
+
+// SAFETY: It is allowed to call `misc_deregister` on a different thread from where you called
+// `misc_register`.
+unsafe impl<T> Send for MiscDeviceRegistration<T> {}
+// SAFETY: All `&self` methods on this type are written to ensure that it is safe to call them in
+// parallel.
+unsafe impl<T> Sync for MiscDeviceRegistration<T> {}
+
+impl<T: MiscDevice> MiscDeviceRegistration<T> {
+    /// Register a misc device.
+    pub fn register(opts: MiscDeviceOptions) -> impl PinInit<Self, Error> {
+        try_pin_init!(Self {
+            inner <- Opaque::try_ffi_init(move |slot: *mut bindings::miscdevice| {
+                // SAFETY: The initializer can write to the provided `slot`.
+                unsafe { slot.write(opts.into_raw::<T>()) };
+
+                // SAFETY: We just wrote the misc device options to the slot. The miscdevice will
+                // get unregistered before `slot` is deallocated because the memory is pinned and
+                // the destructor of this type deallocates the memory.
+                // INVARIANT: If this returns `Ok(())`, then the `slot` will contain a registered
+                // misc device.
+                to_result(unsafe { bindings::misc_register(slot) })
+            }),
+            _t: PhantomData,
+        })
+    }
+
+    /// Returns a raw pointer to the misc device.
+    pub fn as_raw(&self) -> *mut bindings::miscdevice {
+        self.inner.get()
+    }
+}
+
+#[pinned_drop]
+impl<T> PinnedDrop for MiscDeviceRegistration<T> {
+    fn drop(self: Pin<&mut Self>) {
+        // SAFETY: We know that the device is registered by the type invariants.
+        unsafe { bindings::misc_deregister(self.inner.get()) };
+    }
+}
+
+/// Trait implemented by the private data of an open misc device.
+#[vtable]
+pub trait MiscDevice {
+    /// What kind of pointer should `Self` be wrapped in.
+    type Ptr: ForeignOwnable + Send + Sync;
+
+    /// Called when the misc device is opened.
+    ///
+    /// The returned pointer will be stored as the private data for the file.
+    fn open() -> Result<Self::Ptr>;
+
+    /// Called when the misc device is released.
+    fn release(device: Self::Ptr) {
+        drop(device);
+    }
+
+    /// Handler for ioctls.
+    ///
+    /// The `cmd` argument is usually manipulated using the utilties in [`kernel::ioctl`].
+    ///
+    /// [`kernel::ioctl`]: mod@crate::ioctl
+    fn ioctl(
+        _device: <Self::Ptr as ForeignOwnable>::Borrowed<'_>,
+        _cmd: u32,
+        _arg: usize,
+    ) -> Result<isize> {
+        kernel::build_error(VTABLE_DEFAULT_ERROR)
+    }
+
+    /// Handler for ioctls.
+    ///
+    /// Used for 32-bit userspace on 64-bit platforms.
+    ///
+    /// This method is optional and only needs to be provided if the ioctl relies on structures
+    /// that have different layout on 32-bit and 64-bit userspace. If no implementation is
+    /// provided, then `compat_ptr_ioctl` will be used instead.
+    #[cfg(CONFIG_COMPAT)]
+    fn compat_ioctl(
+        _device: <Self::Ptr as ForeignOwnable>::Borrowed<'_>,
+        _cmd: u32,
+        _arg: usize,
+    ) -> Result<isize> {
+        kernel::build_error(VTABLE_DEFAULT_ERROR)
+    }
+}
+
+const fn create_vtable<T: MiscDevice>() -> &'static bindings::file_operations {
+    const fn maybe_fn<T: Copy>(check: bool, func: T) -> Option<T> {
+        if check {
+            Some(func)
+        } else {
+            None
+        }
+    }
+
+    struct VtableHelper<T: MiscDevice> {
+        _t: PhantomData<T>,
+    }
+    impl<T: MiscDevice> VtableHelper<T> {
+        const VTABLE: bindings::file_operations = bindings::file_operations {
+            open: Some(fops_open::<T>),
+            release: Some(fops_release::<T>),
+            unlocked_ioctl: maybe_fn(T::HAS_IOCTL, fops_ioctl::<T>),
+            #[cfg(CONFIG_COMPAT)]
+            compat_ioctl: if T::HAS_COMPAT_IOCTL {
+                Some(fops_compat_ioctl::<T>)
+            } else if T::HAS_IOCTL {
+                Some(bindings::compat_ptr_ioctl)
+            } else {
+                None
+            },
+            // SAFETY: All zeros is a valid value for `bindings::file_operations`.
+            ..unsafe { MaybeUninit::zeroed().assume_init() }
+        };
+    }
+
+    &VtableHelper::<T>::VTABLE
+}
+
+/// # Safety
+///
+/// `file` and `inode` must be the file and inode for a file that is undergoing initialization.
+/// The file must be associated with a `MiscDeviceRegistration<T>`.
+unsafe extern "C" fn fops_open<T: MiscDevice>(
+    inode: *mut bindings::inode,
+    file: *mut bindings::file,
+) -> c_int {
+    // SAFETY: The pointers are valid and for a file being opened.
+    let ret = unsafe { bindings::generic_file_open(inode, file) };
+    if ret != 0 {
+        return ret;
+    }
+
+    let ptr = match T::open() {
+        Ok(ptr) => ptr,
+        Err(err) => return err.to_errno(),
+    };
+
+    // SAFETY: The open call of a file owns the private data.
+    unsafe { (*file).private_data = ptr.into_foreign().cast_mut() };
+
+    0
+}
+
+/// # Safety
+///
+/// `file` and `inode` must be the file and inode for a file that is being released. The file must
+/// be associated with a `MiscDeviceRegistration<T>`.
+unsafe extern "C" fn fops_release<T: MiscDevice>(
+    _inode: *mut bindings::inode,
+    file: *mut bindings::file,
+) -> c_int {
+    // SAFETY: The release call of a file owns the private data.
+    let private = unsafe { (*file).private_data };
+    // SAFETY: The release call of a file owns the private data.
+    let ptr = unsafe { <T::Ptr as ForeignOwnable>::from_foreign(private) };
+
+    T::release(ptr);
+
+    0
+}
+
+/// # Safety
+///
+/// `file` must be a valid file that is associated with a `MiscDeviceRegistration<T>`.
+unsafe extern "C" fn fops_ioctl<T: MiscDevice>(
+    file: *mut bindings::file,
+    cmd: c_uint,
+    arg: c_ulong,
+) -> c_long {
+    // SAFETY: The ioctl call of a file can access the private data.
+    let private = unsafe { (*file).private_data };
+    // SAFETY: Ioctl calls can borrow the private data of the file.
+    let device = unsafe { <T::Ptr as ForeignOwnable>::borrow(private) };
+
+    match T::ioctl(device, cmd, arg as usize) {
+        Ok(ret) => ret as c_long,
+        Err(err) => err.to_errno() as c_long,
+    }
+}
+
+/// # Safety
+///
+/// `file` must be a valid file that is associated with a `MiscDeviceRegistration<T>`.
+#[cfg(CONFIG_COMPAT)]
+unsafe extern "C" fn fops_compat_ioctl<T: MiscDevice>(
+    file: *mut bindings::file,
+    cmd: c_uint,
+    arg: c_ulong,
+) -> c_long {
+    // SAFETY: The compat ioctl call of a file can access the private data.
+    let private = unsafe { (*file).private_data };
+    // SAFETY: Ioctl calls can borrow the private data of the file.
+    let device = unsafe { <T::Ptr as ForeignOwnable>::borrow(private) };
+
+    match T::compat_ioctl(device, cmd, arg as usize) {
+        Ok(ret) => ret as c_long,
+        Err(err) => err.to_errno() as c_long,
+    }
+}
diff --git a/rust/kernel/prelude.rs b/rust/kernel/prelude.rs
index 8bdab9aa0d16..9ab4e0b6cbc9 100644
--- a/rust/kernel/prelude.rs
+++ b/rust/kernel/prelude.rs
@@ -24,6 +24,8 @@ pub use super::build_assert;
 // `super::std_vendor` is hidden, which makes the macro inline for some reason.
 #[doc(no_inline)]
 pub use super::dbg;
+pub use super::fmt;
+pub use super::{dev_alert, dev_crit, dev_dbg, dev_emerg, dev_err, dev_info, dev_notice, dev_warn};
 pub use super::{pr_alert, pr_crit, pr_debug, pr_emerg, pr_err, pr_info, pr_notice, pr_warn};
 
 pub use super::{init, pin_init, try_init, try_pin_init};
diff --git a/rust/kernel/types.rs b/rust/kernel/types.rs
index 7a133d938551..ec6457bb3084 100644
--- a/rust/kernel/types.rs
+++ b/rust/kernel/types.rs
@@ -300,6 +300,22 @@ impl<T> Opaque<T> {
         }
     }
 
+    /// Creates a fallible pin-initializer from the given initializer closure.
+    ///
+    /// The returned initializer calls the given closure with the pointer to the inner `T` of this
+    /// `Opaque`. Since this memory is uninitialized, the closure is not allowed to read from it.
+    ///
+    /// This function is safe, because the `T` inside of an `Opaque` is allowed to be
+    /// uninitialized. Additionally, access to the inner `T` requires `unsafe`, so the caller needs
+    /// to verify at that point that the inner value is valid.
+    pub fn try_ffi_init<E>(
+        init_func: impl FnOnce(*mut T) -> Result<(), E>,
+    ) -> impl PinInit<Self, E> {
+        // SAFETY: We contain a `MaybeUninit`, so it is OK for the `init_func` to not fully
+        // initialize the `T`.
+        unsafe { init::pin_init_from_closure::<_, E>(move |slot| init_func(Self::raw_get(slot))) }
+    }
+
     /// Returns a raw pointer to the opaque data.
     pub const fn get(&self) -> *mut T {
         UnsafeCell::get(&self.value).cast::<T>()
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index e7a087b7e884..2587f41b0d39 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -232,6 +232,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
             mod __module_init {{
                 mod __module_init {{
                     use super::super::{type_};
+                    use kernel::init::PinInit;
 
                     /// The \"Rust loadable module\" mark.
                     //
@@ -242,7 +243,8 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
                     #[used]
                     static __IS_RUST_MODULE: () = ();
 
-                    static mut __MOD: Option<{type_}> = None;
+                    static mut __MOD: core::mem::MaybeUninit<{type_}> =
+                        core::mem::MaybeUninit::uninit();
 
                     // Loadable modules need to export the `{{init,cleanup}}_module` identifiers.
                     /// # Safety
@@ -331,20 +333,14 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
                     ///
                     /// This function must only be called once.
                     unsafe fn __init() -> kernel::ffi::c_int {{
-                        match <{type_} as kernel::Module>::init(&super::super::THIS_MODULE) {{
-                            Ok(m) => {{
-                                // SAFETY: No data race, since `__MOD` can only be accessed by this
-                                // module and there only `__init` and `__exit` access it. These
-                                // functions are only called once and `__exit` cannot be called
-                                // before or during `__init`.
-                                unsafe {{
-                                    __MOD = Some(m);
-                                }}
-                                return 0;
-                            }}
-                            Err(e) => {{
-                                return e.to_errno();
-                            }}
+                        let initer =
+                            <{type_} as kernel::InPlaceModule>::init(&super::super::THIS_MODULE);
+                        // SAFETY: No data race, since `__MOD` can only be accessed by this module
+                        // and there only `__init` and `__exit` access it. These functions are only
+                        // called once and `__exit` cannot be called before or during `__init`.
+                        match unsafe {{ initer.__pinned_init(__MOD.as_mut_ptr()) }} {{
+                            Ok(m) => 0,
+                            Err(e) => e.to_errno(),
                         }}
                     }}
 
@@ -359,7 +355,7 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
                         // called once and `__init` was already called.
                         unsafe {{
                             // Invokes `drop()` on `__MOD`, which should be used for cleanup.
-                            __MOD = None;
+                            __MOD.assume_init_drop();
                         }}
                     }}