Merge tag 'char-misc-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull Char/Misc/IIO/Binder updates from Greg KH:
 "Here is the big set of char/misc/iio and other driver subsystem
  changes for 6.18-rc1.

  Loads of different stuff in here, it was a busy development cycle in
  lots of different subsystems, with over 27k new lines added to the
  tree.

  Included in here are:

   - IIO updates including new drivers, reworking of existing apis, and
     other goodness in the sensor subsystems

   - MEI driver updates and additions

   - NVMEM driver updates

   - slimbus removal for an unused driver and some other minor updates

   - coresight driver updates and additions

   - MHI driver updates

   - comedi driver updates and fixes

   - extcon driver updates

   - interconnect driver additions

   - eeprom driver updates and fixes

   - minor UIO driver updates

   - tiny W1 driver updates

  But the majority of new code is in the rust bindings and additions,
  which includes:

   - misc driver rust binding updates for read/write support, we can now
     write "normal" misc drivers in rust fully, and the sample driver
     shows how this can be done.

   - Initial framework for USB driver rust bindings, which are disabled
     for now in the build, due to limited support, but coming in through
     this tree due to dependencies on other rust binding changes that
     were in here. I'll be enabling these back on in the build in the
     usb.git tree after -rc1 is out so that developers can continue to
     work on these in linux-next over the next development cycle.

   - Android Binder driver implemented in Rust.

     This is the big one, and was driving a huge majority of the rust
     binding work over the past years. Right now there are two binder
     drivers in the kernel, selected only at build time as to which one
     to use as binder wants to be included in the system at boot time.

     The binder C maintainers all agreed on this, as eventually, they
     want the C code to be removed from the tree, but it will take a few
     releases to get there while both are maintained to ensure that the
     rust implementation is fully stable and compliant with the existing
     userspace apis.

  All of these have been in linux-next for a while"

* tag 'char-misc-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (320 commits)
  rust: usb: keep usb::Device private for now
  rust: usb: don't retain device context for the interface parent
  USB: disable rust bindings from the build for now
  samples: rust: add a USB driver sample
  rust: usb: add basic USB abstractions
  coresight: Add label sysfs node support
  dt-bindings: arm: Add label in the coresight components
  coresight: tnoc: add new AMBA ID to support Trace Noc V2
  coresight: Fix incorrect handling for return value of devm_kzalloc
  coresight: tpda: fix the logic to setup the element size
  coresight: trbe: Return NULL pointer for allocation failures
  coresight: Refactor runtime PM
  coresight: Make clock sequence consistent
  coresight: Refactor driver data allocation
  coresight: Consolidate clock enabling
  coresight: Avoid enable programming clock duplicately
  coresight: Appropriately disable trace bus clocks
  coresight: Appropriately disable programming clocks
  coresight: etm4x: Support atclk
  coresight: catu: Support atclk
  ...

4 files changed, 94 insertions, 4 deletions

diff --git a/samples/rust/Kconfig b/samples/rust/Kconfig
index 66360cdf048f..c376eb899b7a 100644
--- a/samples/rust/Kconfig
+++ b/samples/rust/Kconfig
@@ -105,6 +105,17 @@ config SAMPLE_RUST_DRIVER_PLATFORM
 
 	  If unsure, say N.
 
+config SAMPLE_RUST_DRIVER_USB
+	tristate "USB Driver"
+	depends on USB = y && BROKEN
+	help
+	  This option builds the Rust USB driver sample.
+
+	  To compile this as a module, choose M here:
+	  the module will be called rust_driver_usb.
+
+	  If unsure, say N.
+
 config SAMPLE_RUST_DRIVER_FAUX
 	tristate "Faux Driver"
 	help
diff --git a/samples/rust/Makefile b/samples/rust/Makefile
index 69ca01497b58..cf8422f8f219 100644
--- a/samples/rust/Makefile
+++ b/samples/rust/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_SAMPLE_RUST_DEBUGFS_SCOPED)	+= rust_debugfs_scoped.o
 obj-$(CONFIG_SAMPLE_RUST_DMA)			+= rust_dma.o
 obj-$(CONFIG_SAMPLE_RUST_DRIVER_PCI)		+= rust_driver_pci.o
 obj-$(CONFIG_SAMPLE_RUST_DRIVER_PLATFORM)	+= rust_driver_platform.o
+obj-$(CONFIG_SAMPLE_RUST_DRIVER_USB)		+= rust_driver_usb.o
 obj-$(CONFIG_SAMPLE_RUST_DRIVER_FAUX)		+= rust_driver_faux.o
 obj-$(CONFIG_SAMPLE_RUST_DRIVER_AUXILIARY)	+= rust_driver_auxiliary.o
 obj-$(CONFIG_SAMPLE_RUST_CONFIGFS)		+= rust_configfs.o
diff --git a/samples/rust/rust_driver_usb.rs b/samples/rust/rust_driver_usb.rs
new file mode 100644
index 000000000000..5c396f421de7
--- /dev/null
+++ b/samples/rust/rust_driver_usb.rs
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0
+// SPDX-FileCopyrightText: Copyright (C) 2025 Collabora Ltd.
+
+//! Rust USB driver sample.
+
+use kernel::{device, device::Core, prelude::*, sync::aref::ARef, usb};
+
+struct SampleDriver {
+    _intf: ARef<usb::Interface>,
+}
+
+kernel::usb_device_table!(
+    USB_TABLE,
+    MODULE_USB_TABLE,
+    <SampleDriver as usb::Driver>::IdInfo,
+    [(usb::DeviceId::from_id(0x1234, 0x5678), ()),]
+);
+
+impl usb::Driver for SampleDriver {
+    type IdInfo = ();
+    const ID_TABLE: usb::IdTable<Self::IdInfo> = &USB_TABLE;
+
+    fn probe(
+        intf: &usb::Interface<Core>,
+        _id: &usb::DeviceId,
+        _info: &Self::IdInfo,
+    ) -> Result<Pin<KBox<Self>>> {
+        let dev: &device::Device<Core> = intf.as_ref();
+        dev_info!(dev, "Rust USB driver sample probed\n");
+
+        let drvdata = KBox::new(Self { _intf: intf.into() }, GFP_KERNEL)?;
+        Ok(drvdata.into())
+    }
+
+    fn disconnect(intf: &usb::Interface<Core>, _data: Pin<&Self>) {
+        let dev: &device::Device<Core> = intf.as_ref();
+        dev_info!(dev, "Rust USB driver sample disconnected\n");
+    }
+}
+
+kernel::module_usb_driver! {
+    type: SampleDriver,
+    name: "rust_driver_usb",
+    authors: ["Daniel Almeida"],
+    description: "Rust USB driver sample",
+    license: "GPL v2",
+}
diff --git a/samples/rust/rust_misc_device.rs b/samples/rust/rust_misc_device.rs
index e7ab77448f75..d69bc33dbd99 100644
--- a/samples/rust/rust_misc_device.rs
+++ b/samples/rust/rust_misc_device.rs
@@ -100,13 +100,13 @@ use core::pin::Pin;
 use kernel::{
     c_str,
     device::Device,
-    fs::File,
+    fs::{File, Kiocb},
     ioctl::{_IO, _IOC_SIZE, _IOR, _IOW},
+    iov::{IovIterDest, IovIterSource},
     miscdevice::{MiscDevice, MiscDeviceOptions, MiscDeviceRegistration},
     new_mutex,
     prelude::*,
-    sync::Mutex,
-    types::ARef,
+    sync::{aref::ARef, Mutex},
     uaccess::{UserSlice, UserSliceReader, UserSliceWriter},
 };
 
@@ -144,6 +144,7 @@ impl kernel::InPlaceModule for RustMiscDeviceModule {
 
 struct Inner {
     value: i32,
+    buffer: KVVec<u8>,
 }
 
 #[pin_data(PinnedDrop)]
@@ -165,7 +166,10 @@ impl MiscDevice for RustMiscDevice {
         KBox::try_pin_init(
             try_pin_init! {
                 RustMiscDevice {
-                    inner <- new_mutex!( Inner{ value: 0_i32 } ),
+                    inner <- new_mutex!(Inner {
+                        value: 0_i32,
+                        buffer: KVVec::new(),
+                    }),
                     dev: dev,
                 }
             },
@@ -173,6 +177,33 @@ impl MiscDevice for RustMiscDevice {
         )
     }
 
+    fn read_iter(mut kiocb: Kiocb<'_, Self::Ptr>, iov: &mut IovIterDest<'_>) -> Result<usize> {
+        let me = kiocb.file();
+        dev_info!(me.dev, "Reading from Rust Misc Device Sample\n");
+
+        let inner = me.inner.lock();
+        // Read the buffer contents, taking the file position into account.
+        let read = iov.simple_read_from_buffer(kiocb.ki_pos_mut(), &inner.buffer)?;
+
+        Ok(read)
+    }
+
+    fn write_iter(mut kiocb: Kiocb<'_, Self::Ptr>, iov: &mut IovIterSource<'_>) -> Result<usize> {
+        let me = kiocb.file();
+        dev_info!(me.dev, "Writing to Rust Misc Device Sample\n");
+
+        let mut inner = me.inner.lock();
+
+        // Replace buffer contents.
+        inner.buffer.clear();
+        let len = iov.copy_from_iter_vec(&mut inner.buffer, GFP_KERNEL)?;
+
+        // Set position to zero so that future `read` calls will see the new contents.
+        *kiocb.ki_pos_mut() = 0;
+
+        Ok(len)
+    }
+
     fn ioctl(me: Pin<&RustMiscDevice>, _file: &File, cmd: u32, arg: usize) -> Result<isize> {
         dev_info!(me.dev, "IOCTLing Rust Misc Device Sample\n");