[PATCH v2 1/3] rust: core abstractions for network PHY drivers

FUJITA Tomonori
2023-10-06T09:49:25Z

This patch adds abstractions to implement network PHY drivers; the
driver registration and bindings for some of callback functions in
struct phy_driver and many genphy_ functions.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
---
init/Kconfig | 1 +
rust/Makefile | 1 +
rust/bindings/bindings_helper.h | 3 +
rust/kernel/lib.rs | 2 +
rust/kernel/net.rs | 5 +
rust/kernel/net/phy.rs | 706 ++++++++++++++++++++++++++++++++
6 files changed, 718 insertions(+)
create mode 100644 rust/kernel/net.rs
create mode 100644 rust/kernel/net/phy.rs

diff --git a/init/Kconfig b/init/Kconfig
index 6d35728b94b2..4b4e3df1658d 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1889,6 +1889,7 @@ config RUST
depends on !GCC_PLUGINS
depends on !RANDSTRUCT
depends on !DEBUG_INFO_BTF || PAHOLE_HAS_LANG_EXCLUDE
+ depends on PHYLIB=y
select CONSTRUCTORS
help
Enables Rust support in the kernel.
diff --git a/rust/Makefile b/rust/Makefile
index 87958e864be0..f67e55945b36 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -331,6 +331,7 @@ quiet_cmd_bindgen = BINDGEN $@
cmd_bindgen = \
$(BINDGEN) $< $(bindgen_target_flags) \
--use-core --with-derive-default --ctypes-prefix core::ffi --no-layout-tests \
+ --rustified-enum phy_state\
--no-debug '.*' \
-o $@ -- $(bindgen_c_flags_final) -DMODULE \
$(bindgen_target_cflags) $(bindgen_target_extra)
diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index c91a3c24f607..ec4ee09a34ad 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -8,6 +8,9 @@

#include <kunit/test.h>
#include <linux/errname.h>
+#include <linux/ethtool.h>
+#include <linux/mdio.h>
+#include <linux/phy.h>
#include <linux/slab.h>
#include <linux/refcount.h>
#include <linux/wait.h>
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index e8811700239a..f9883bde4459 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -14,6 +14,7 @@
#![no_std]
#![feature(allocator_api)]
#![feature(coerce_unsized)]
+#![feature(const_maybe_uninit_zeroed)]
#![feature(dispatch_from_dyn)]
#![feature(new_uninit)]
#![feature(receiver_trait)]
@@ -36,6 +37,7 @@
pub mod ioctl;
#[cfg(CONFIG_KUNIT)]
pub mod kunit;
+pub mod net;
pub mod prelude;
pub mod print;
mod static_assert;
diff --git a/rust/kernel/net.rs b/rust/kernel/net.rs
new file mode 100644
index 000000000000..fbb6d9683012
--- /dev/null
+++ b/rust/kernel/net.rs
@@ -0,0 +1,5 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Networking.
+
+pub mod phy;
diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs
new file mode 100644
index 000000000000..d06a83ad8a8a
--- /dev/null
+++ b/rust/kernel/net/phy.rs
@@ -0,0 +1,706 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Network PHY device.
+//!
+//! C headers: [`include/linux/phy.h`](../../../../include/linux/phy.h).
+
+use crate::{bindings, error::*, prelude::vtable, str::CStr, types::Opaque};
+use core::marker::PhantomData;
+
+/// Corresponds to the kernel's `enum phy_state`.
+#[derive(PartialEq)]
+pub enum DeviceState {
+ /// PHY device and driver are not ready for anything.
+ Down,
+ /// PHY is ready to send and receive packets.
+ Ready,
+ /// PHY is up, but no polling or interrupts are done.
+ Halted,
+ /// PHY is up, but is in an error state.
+ Error,
+ /// PHY and attached device are ready to do work.
+ Up,
+ /// PHY is currently running.
+ Running,
+ /// PHY is up, but not currently plugged in.
+ NoLink,
+ /// PHY is performing a cable test.
+ CableTest,
+}
+
+/// Represents duplex mode.
+pub enum DuplexMode {
+ /// Full-duplex mode
+ Half,
+ /// Half-duplex mode
+ Full,
+ /// Unknown
+ Unknown,
+}
+
+/// Wraps the kernel's `struct phy_device`.
+///
+/// # Invariants
+///
+/// `self.0` is always in a valid state.
+#[repr(transparent)]
+pub struct Device(Opaque<bindings::phy_device>);
+
+impl Device {
+ /// Creates a new [`Device`] instance from a raw pointer.
+ ///
+ /// # Safety
+ ///
+ /// For the duration of the lifetime 'a, the pointer must be valid for writing and nobody else
+ /// may read or write to the `phy_device` object.
+ pub unsafe fn from_raw<'a>(ptr: *mut bindings::phy_device) -> &'a mut Self {
+ unsafe { &mut *ptr.cast() }
+ }
+
+ /// Gets the id of the PHY.
+ pub fn phy_id(&mut self) -> u32 {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ unsafe { (*phydev).phy_id }
+ }
+
+ /// Gets the state of the PHY.
+ pub fn state(&mut self) -> DeviceState {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ let state = unsafe { (*phydev).state };
+ match state {
+ bindings::phy_state::PHY_DOWN => DeviceState::Down,
+ bindings::phy_state::PHY_READY => DeviceState::Ready,
+ bindings::phy_state::PHY_HALTED => DeviceState::Halted,
+ bindings::phy_state::PHY_ERROR => DeviceState::Error,
+ bindings::phy_state::PHY_UP => DeviceState::Up,
+ bindings::phy_state::PHY_RUNNING => DeviceState::Running,
+ bindings::phy_state::PHY_NOLINK => DeviceState::NoLink,
+ bindings::phy_state::PHY_CABLETEST => DeviceState::CableTest,
+ }
+ }
+
+ /// Returns true if the link is up.
+ pub fn get_link(&mut self) -> bool {
+ const LINK_IS_UP: u32 = 1;
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ unsafe { (*phydev).link() == LINK_IS_UP }
+ }
+
+ /// Returns true if auto-negotiation is enabled.
+ pub fn is_autoneg_enabled(&mut self) -> bool {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ unsafe { (*phydev).autoneg() == bindings::AUTONEG_ENABLE }
+ }
+
+ /// Returns true if auto-negotiation is completed.
+ pub fn is_autoneg_completed(&mut self) -> bool {
+ const AUTONEG_COMPLETED: u32 = 1;
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ unsafe { (*phydev).autoneg_complete() == AUTONEG_COMPLETED }
+ }
+
+ /// Sets the speed of the PHY.
+ pub fn set_speed(&mut self, speed: u32) {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ unsafe { (*phydev).speed = speed as i32 };
+ }
+
+ /// Sets duplex mode.
+ pub fn set_duplex(&mut self, mode: DuplexMode) {
+ let phydev = self.0.get();
+ let v = match mode {
+ DuplexMode::Full => bindings::DUPLEX_FULL as i32,
+ DuplexMode::Half => bindings::DUPLEX_HALF as i32,
+ DuplexMode::Unknown => bindings::DUPLEX_UNKNOWN as i32,
+ };
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ unsafe { (*phydev).duplex = v };
+ }
+
+ /// Reads a given C22 PHY register.
+ pub fn read(&mut self, regnum: u16) -> Result<u16> {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ let ret = unsafe {
+ bindings::mdiobus_read((*phydev).mdio.bus, (*phydev).mdio.addr, regnum.into())
+ };
+ if ret < 0 {
+ Err(Error::from_errno(ret))
+ } else {
+ Ok(ret as u16)
+ }
+ }
+
+ /// Writes a given C22 PHY register.
+ pub fn write(&mut self, regnum: u16, val: u16) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe {
+ bindings::mdiobus_write((*phydev).mdio.bus, (*phydev).mdio.addr, regnum.into(), val)
+ })
+ }
+
+ /// Reads a paged register.
+ pub fn read_paged(&mut self, page: u16, regnum: u16) -> Result<u16> {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ let ret = unsafe { bindings::phy_read_paged(phydev, page.into(), regnum.into()) };
+ if ret < 0 {
+ Err(Error::from_errno(ret))
+ } else {
+ Ok(ret as u16)
+ }
+ }
+
+ /// Resolves the advertisements into PHY settings.
+ pub fn resolve_aneg_linkmode(&mut self) {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ unsafe { bindings::phy_resolve_aneg_linkmode(phydev) };
+ }
+
+ /// Executes software reset the PHY via BMCR_RESET bit.
+ pub fn genphy_soft_reset(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe { bindings::genphy_soft_reset(phydev) })
+ }
+
+ /// Initializes the PHY.
+ pub fn init_hw(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // so an FFI call with a valid pointer.
+ to_result(unsafe { bindings::phy_init_hw(phydev) })
+ }
+
+ /// Starts auto-negotiation.
+ pub fn start_aneg(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe { bindings::phy_start_aneg(phydev) })
+ }
+
+ /// Resumes the PHY via BMCR_PDOWN bit.
+ pub fn genphy_resume(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe { bindings::genphy_resume(phydev) })
+ }
+
+ /// Suspends the PHY via BMCR_PDOWN bit.
+ pub fn genphy_suspend(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe { bindings::genphy_suspend(phydev) })
+ }
+
+ /// Checks the link status and updates current link state.
+ pub fn genphy_read_status(&mut self) -> Result<u16> {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ let ret = unsafe { bindings::genphy_read_status(phydev) };
+ if ret < 0 {
+ Err(Error::from_errno(ret))
+ } else {
+ Ok(ret as u16)
+ }
+ }
+
+ /// Updates the link status.
+ pub fn genphy_update_link(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe { bindings::genphy_update_link(phydev) })
+ }
+
+ /// Reads Link partner ability.
+ pub fn genphy_read_lpa(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe { bindings::genphy_read_lpa(phydev) })
+ }
+
+ /// Reads PHY abilities.
+ pub fn genphy_read_abilities(&mut self) -> Result {
+ let phydev = self.0.get();
+ // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
+ // So an FFI call with a valid pointer.
+ to_result(unsafe { bindings::genphy_read_abilities(phydev) })
+ }
+}
+
+/// Defines certain other features this PHY supports (like interrupts).
+pub mod flags {
+ /// PHY is internal.
+ pub const IS_INTERNAL: u32 = bindings::PHY_IS_INTERNAL;
+ /// PHY needs to be reset after the refclk is enabled.
+ pub const RST_AFTER_CLK_EN: u32 = bindings::PHY_RST_AFTER_CLK_EN;
+ /// Polling is used to detect PHY status changes.
+ pub const POLL_CABLE_TEST: u32 = bindings::PHY_POLL_CABLE_TEST;
+ /// Don't suspend.
+ pub const ALWAYS_CALL_SUSPEND: u32 = bindings::PHY_ALWAYS_CALL_SUSPEND;
+}
+
+/// An adapter for the registration of a PHY driver.
+struct Adapter<T: Driver> {
+ _p: PhantomData<T>,
+}
+
+impl<T: Driver> Adapter<T> {
+ unsafe extern "C" fn soft_reset_callback(
+ phydev: *mut bindings::phy_device,
+ ) -> core::ffi::c_int {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::soft_reset(dev)?;
+ Ok(0)
+ })
+ }
+
+ unsafe extern "C" fn get_features_callback(
+ phydev: *mut bindings::phy_device,
+ ) -> core::ffi::c_int {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::get_features(dev)?;
+ Ok(0)
+ })
+ }
+
+ unsafe extern "C" fn suspend_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::suspend(dev)?;
+ Ok(0)
+ })
+ }
+
+ unsafe extern "C" fn resume_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::resume(dev)?;
+ Ok(0)
+ })
+ }
+
+ unsafe extern "C" fn config_aneg_callback(
+ phydev: *mut bindings::phy_device,
+ ) -> core::ffi::c_int {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::config_aneg(dev)?;
+ Ok(0)
+ })
+ }
+
+ unsafe extern "C" fn read_status_callback(
+ phydev: *mut bindings::phy_device,
+ ) -> core::ffi::c_int {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::read_status(dev)?;
+ Ok(0)
+ })
+ }
+
+ unsafe extern "C" fn match_phy_device_callback(
+ phydev: *mut bindings::phy_device,
+ ) -> core::ffi::c_int {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::match_phy_device(dev) as i32
+ }
+
+ unsafe extern "C" fn read_mmd_callback(
+ phydev: *mut bindings::phy_device,
+ devnum: i32,
+ regnum: u16,
+ ) -> i32 {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ let ret = T::read_mmd(dev, devnum as u8, regnum)?;
+ Ok(ret.into())
+ })
+ }
+
+ unsafe extern "C" fn write_mmd_callback(
+ phydev: *mut bindings::phy_device,
+ devnum: i32,
+ regnum: u16,
+ val: u16,
+ ) -> i32 {
+ from_result(|| {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::write_mmd(dev, devnum as u8, regnum, val)?;
+ Ok(0)
+ })
+ }
+
+ unsafe extern "C" fn link_change_notify_callback(phydev: *mut bindings::phy_device) {
+ // SAFETY: The C API guarantees that `phydev` is valid while this function is running.
+ let dev = unsafe { Device::from_raw(phydev) };
+ T::link_change_notify(dev);
+ }
+}
+
+/// Creates the kernel's `phy_driver` instance.
+///
+/// This is used by [`module_phy_driver`] macro to create a static array of phy_driver`.
+pub const fn create_phy_driver<T: Driver>() -> Opaque<bindings::phy_driver> {
+ Opaque::new(bindings::phy_driver {
+ name: T::NAME.as_char_ptr() as *mut i8,
+ flags: T::FLAGS,
+ phy_id: T::PHY_DEVICE_ID.id,
+ phy_id_mask: T::PHY_DEVICE_ID.mask_as_int(),
+ soft_reset: if T::HAS_SOFT_RESET {
+ Some(Adapter::<T>::soft_reset_callback)
+ } else {
+ None
+ },
+ get_features: if T::HAS_GET_FEATURES {
+ Some(Adapter::<T>::get_features_callback)
+ } else {
+ None
+ },
+ match_phy_device: if T::HAS_MATCH_PHY_DEVICE {
+ Some(Adapter::<T>::match_phy_device_callback)
+ } else {
+ None
+ },
+ suspend: if T::HAS_SUSPEND {
+ Some(Adapter::<T>::suspend_callback)
+ } else {
+ None
+ },
+ resume: if T::HAS_RESUME {
+ Some(Adapter::<T>::resume_callback)
+ } else {
+ None
+ },
+ config_aneg: if T::HAS_CONFIG_ANEG {
+ Some(Adapter::<T>::config_aneg_callback)
+ } else {
+ None
+ },
+ read_status: if T::HAS_READ_STATUS {
+ Some(Adapter::<T>::read_status_callback)
+ } else {
+ None
+ },
+ read_mmd: if T::HAS_READ_MMD {
+ Some(Adapter::<T>::read_mmd_callback)
+ } else {
+ None
+ },
+ write_mmd: if T::HAS_WRITE_MMD {
+ Some(Adapter::<T>::write_mmd_callback)
+ } else {
+ None
+ },
+ link_change_notify: if T::HAS_LINK_CHANGE_NOTIFY {
+ Some(Adapter::<T>::link_change_notify_callback)
+ } else {
+ None
+ },
+ // SAFETY: The rest is zeroed out to initialize `struct phy_driver`,
+ // sets `Option<&F>` to be `None`.
+ ..unsafe { core::mem::MaybeUninit::<bindings::phy_driver>::zeroed().assume_init() }
+ })
+}
+
+/// Corresponds to functions in `struct phy_driver`.
+///
+/// This is used to register a PHY driver.
+#[vtable]
+pub trait Driver {
+ /// Defines certain other features this PHY supports.
+ const FLAGS: u32 = 0;
+ /// The friendly name of this PHY type.
+ const NAME: &'static CStr;
+ /// This driver only works for PHYs with IDs which match this field.
+ const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_custom_mask(0, 0);
+
+ /// Issues a PHY software reset.
+ fn soft_reset(_dev: &mut Device) -> Result {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Probes the hardware to determine what abilities it has.
+ fn get_features(_dev: &mut Device) -> Result {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Returns true if this is a suitable driver for the given phydev.
+ /// If not implemented, matching is based on [`PHY_DEVICE_ID`].
+ fn match_phy_device(_dev: &mut Device) -> bool {
+ false
+ }
+
+ /// Configures the advertisement and resets auto-negotiation
+ /// if auto-negotiation is enabled.
+ fn config_aneg(_dev: &mut Device) -> Result {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Determines the negotiated speed and duplex.
+ fn read_status(_dev: &mut Device) -> Result<u16> {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Suspends the hardware, saving state if needed.
+ fn suspend(_dev: &mut Device) -> Result {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Resumes the hardware, restoring state if needed.
+ fn resume(_dev: &mut Device) -> Result {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Overrides the default MMD read function for reading a MMD register.
+ fn read_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16) -> Result<u16> {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Overrides the default MMD write function for writing a MMD register.
+ fn write_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16, _val: u16) -> Result {
+ Err(code::ENOTSUPP)
+ }
+
+ /// Callback for notification of link change.
+ fn link_change_notify(_dev: &mut Device) {}
+}
+
+/// Registration structure for a PHY driver.
+///
+/// # Invariants
+///
+/// The `drivers` points to an array of `struct phy_driver`, which is
+/// registered to the kernel via `phy_drivers_register`.
+pub struct Registration {
+ drivers: Option<&'static [Opaque<bindings::phy_driver>]>,
+}
+
+impl Registration {
+ /// Registers a PHY driver.
+ #[must_use]
+ pub fn register(
+ module: &'static crate::ThisModule,
+ drivers: &'static [Opaque<bindings::phy_driver>],
+ ) -> Result<Self> {
+ if drivers.len() == 0 {
+ return Err(code::EINVAL);
+ }
+ // SAFETY: `drivers` has static lifetime and used only in the C side.
+ to_result(unsafe {
+ bindings::phy_drivers_register(drivers[0].get(), drivers.len() as i32, module.0)
+ })?;
+ Ok(Registration {
+ drivers: Some(drivers),
+ })
+ }
+}
+
+impl Drop for Registration {
+ fn drop(&mut self) {
+ if let Some(drv) = self.drivers.take() {
+ // SAFETY: The type invariants guarantee that self.drivers is valid.
+ unsafe { bindings::phy_drivers_unregister(drv[0].get(), drv.len() as i32) };
+ }
+ }
+}
+
+// SAFETY: `Registration` does not expose any of its state across threads.
+unsafe impl Send for Registration {}
+
+// SAFETY: `Registration` does not expose any of its state across threads.
+unsafe impl Sync for Registration {}
+
+/// Represents the kernel's `struct mdio_device_id`.
+pub struct DeviceId {
+ /// Corresponds to `phy_id` in `struct mdio_device_id`.
+ pub id: u32,
+ mask: DeviceMask,
+}
+
+impl DeviceId {
+ /// Creates a new instance with the exact match mask.
+ pub const fn new_with_exact_mask(id: u32) -> Self {
+ DeviceId {
+ id,
+ mask: DeviceMask::Exact,
+ }
+ }
+
+ /// Creates a new instance with the model match mask.
+ pub const fn new_with_model_mask(id: u32) -> Self {
+ DeviceId {
+ id,
+ mask: DeviceMask::Model,
+ }
+ }
+
+ /// Creates a new instance with the vendor match mask.
+ pub const fn new_with_vendor_mask(id: u32) -> Self {
+ DeviceId {
+ id,
+ mask: DeviceMask::Vendor,
+ }
+ }
+
+ /// Creates a new instance with a custom match mask.
+ pub const fn new_with_custom_mask(id: u32, mask: u32) -> Self {
+ DeviceId {
+ id,
+ mask: DeviceMask::Custom(mask),
+ }
+ }
+
+ /// Creates a new instance from [`Driver`].
+ pub const fn new_with_driver<T: Driver>() -> Self {
+ T::PHY_DEVICE_ID
+ }
+
+ /// Get a mask as u32.
+ pub const fn mask_as_int(self) -> u32 {
+ self.mask.as_int()
+ }
+}
+
+enum DeviceMask {
+ Exact,
+ Model,
+ Vendor,
+ Custom(u32),
+}
+
+impl DeviceMask {
+ const MASK_EXACT: u32 = !0;
+ const MASK_MODEL: u32 = !0 << 4;
+ const MASK_VENDOR: u32 = !0 << 10;
+
+ const fn as_int(self) -> u32 {
+ match self {
+ DeviceMask::Exact => Self::MASK_EXACT,
+ DeviceMask::Model => Self::MASK_MODEL,
+ DeviceMask::Vendor => Self::MASK_VENDOR,
+ DeviceMask::Custom(mask) => mask,
+ }
+ }
+}
+
+/// Declares a kernel module for PHYs drivers.
+///
+/// This creates a static array of `struct phy_driver` and registers it.
+/// This also corresponds to the kernel's MODULE_DEVICE_TABLE macro, which embeds the information
+/// for module loading into the module binary file.
+///
+/// # Examples
+///
+/// ```ignore
+///
+/// use kernel::net::phy::{self, DeviceId, Driver};
+/// use kernel::prelude::*;
+///
+/// kernel::module_phy_driver! {
+/// drivers: [PhyAX88772A, PhyAX88772C, PhyAX88796B],
+/// device_table: [
+/// DeviceId::new_with_driver::<PhyAX88772A>(),
+/// DeviceId::new_with_driver::<PhyAX88772C>(),
+/// DeviceId::new_with_driver::<PhyAX88796B>()
+/// ],
+/// type: RustAsixPhy,
+/// name: "rust_asix_phy",
+/// author: "Rust for Linux Contributors",
+/// description: "Rust Asix PHYs driver",
+/// license: "GPL",
+/// }
+/// ```
+#[macro_export]
+macro_rules! module_phy_driver {
+ (@replace_expr $_t:tt $sub:expr) => {$sub};
+
+ (@count_devices $($x:expr),*) => {
+ 0usize $(+ $crate::module_phy_driver!(@replace_expr $x 1usize))*
+ };
+
+ (@device_table $name:ident, [$($dev:expr),+]) => {
+ ::kernel::macros::paste! {
+ #[no_mangle]
+ static [<__mod_mdio__ $name _device_table>]: [
+ kernel::bindings::mdio_device_id;
+ $crate::module_phy_driver!(@count_devices $($dev),+) + 1
+ ] = [
+ $(kernel::bindings::mdio_device_id {
+ phy_id: $dev.id,
+ phy_id_mask: $dev.mask_as_int()
+ }),+,
+ kernel::bindings::mdio_device_id {
+ phy_id: 0,
+ phy_id_mask: 0
+ }
+ ];
+ }
+ };
+
+ (drivers: [$($driver:ident),+], device_table: [$($dev:expr),+], type: $modname:ident, $($f:tt)*) => {
+ struct Module<$modname> {
+ _reg: kernel::net::phy::Registration,
+ _p: core::marker::PhantomData<$modname>,
+ }
+
+ type ModuleType = Module<$modname>;
+
+ $crate::prelude::module! {
+ type: ModuleType,
+ $($f)*
+ }
+
+ static mut DRIVERS: [
+ kernel::types::Opaque<kernel::bindings::phy_driver>;
+ $crate::module_phy_driver!(@count_devices $($driver),+)
+ ] = [
+ $(kernel::net::phy::create_phy_driver::<$driver>()),+
+ ];
+
+ impl kernel::Module for Module<$modname> {
+ fn init(module: &'static ThisModule) -> Result<Self> {
+ // SAFETY: static `DRIVERS` array is used only in the C side.
+ let mut reg = unsafe { kernel::net::phy::Registration::register(module, &DRIVERS) }?;
+
+ Ok(Module {
+ _reg: reg,
+ _p: core::marker::PhantomData,
+ })
+ }
+ }
+
+ $crate::module_phy_driver!(@device_table $modname, [$($dev),+]);
+ }
+}
--
2.34.1