1 files changed, 52 insertions, 40 deletions

diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs
index fd40b703d224..910ce867480a 100644
--- a/rust/kernel/net/phy.rs
+++ b/rust/kernel/net/phy.rs
@@ -7,8 +7,9 @@
 //! C headers: [`include/linux/phy.h`](srctree/include/linux/phy.h).
 
 use crate::{error::*, prelude::*, types::Opaque};
+use core::{marker::PhantomData, ptr::addr_of_mut};
 
-use core::marker::PhantomData;
+pub mod reg;
 
 /// PHY state machine states.
 ///
@@ -58,8 +59,9 @@ pub enum DuplexMode {
 ///
 /// # Invariants
 ///
-/// Referencing a `phy_device` using this struct asserts that you are in
-/// a context where all methods defined on this struct are safe to call.
+/// - Referencing a `phy_device` using this struct asserts that you are in
+///   a context where all methods defined on this struct are safe to call.
+/// - This struct always has a valid `self.0.mdio.dev`.
 ///
 /// [`struct phy_device`]: srctree/include/linux/phy.h
 // During the calls to most functions in [`Driver`], the C side (`PHYLIB`) holds a lock that is
@@ -76,9 +78,11 @@ impl Device {
     ///
     /// # Safety
     ///
-    /// For the duration of 'a, the pointer must point at a valid `phy_device`,
-    /// and the caller must be in a context where all methods defined on this struct
-    /// are safe to call.
+    /// For the duration of `'a`,
+    /// - the pointer must point at a valid `phy_device`, and the caller
+    ///   must be in a context where all methods defined on this struct
+    ///   are safe to call.
+    /// - `(*ptr).mdio.dev` must be a valid.
     unsafe fn from_raw<'a>(ptr: *mut bindings::phy_device) -> &'a mut Self {
         // CAST: `Self` is a `repr(transparent)` wrapper around `bindings::phy_device`.
         let ptr = ptr.cast::<Self>();
@@ -175,32 +179,15 @@ impl Device {
         unsafe { (*phydev).duplex = v };
     }
 
-    /// Reads a given C22 PHY register.
+    /// Reads a PHY register.
     // This function reads a hardware register and updates the stats so takes `&mut self`.
-    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 it's just an FFI call, open code of `phy_read()` with a valid `phy_device` pointer
-        // `phydev`.
-        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)
-        }
+    pub fn read<R: reg::Register>(&mut self, reg: R) -> Result<u16> {
+        reg.read(self)
     }
 
-    /// 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 it's just an FFI call, open code of `phy_write()` with a valid `phy_device` pointer
-        // `phydev`.
-        to_result(unsafe {
-            bindings::mdiobus_write((*phydev).mdio.bus, (*phydev).mdio.addr, regnum.into(), val)
-        })
+    /// Writes a PHY register.
+    pub fn write<R: reg::Register>(&mut self, reg: R, val: u16) -> Result {
+        reg.write(self, val)
     }
 
     /// Reads a paged register.
@@ -265,16 +252,8 @@ impl Device {
     }
 
     /// 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 it's just an FFI call.
-        let ret = unsafe { bindings::genphy_read_status(phydev) };
-        if ret < 0 {
-            Err(Error::from_errno(ret))
-        } else {
-            Ok(ret as u16)
-        }
+    pub fn genphy_read_status<R: reg::Register>(&mut self) -> Result<u16> {
+        R::read_status(self)
     }
 
     /// Updates the link status.
@@ -302,6 +281,14 @@ impl Device {
     }
 }
 
+impl AsRef<kernel::device::Device> for Device {
+    fn as_ref(&self) -> &kernel::device::Device {
+        let phydev = self.0.get();
+        // SAFETY: The struct invariant ensures that `mdio.dev` is valid.
+        unsafe { kernel::device::Device::as_ref(addr_of_mut!((*phydev).mdio.dev)) }
+    }
+}
+
 /// Defines certain other features this PHY supports (like interrupts).
 ///
 /// These flag values are used in [`Driver::FLAGS`].
@@ -341,6 +328,21 @@ impl<T: Driver> Adapter<T> {
     /// # Safety
     ///
     /// `phydev` must be passed by the corresponding callback in `phy_driver`.
+    unsafe extern "C" fn probe_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int {
+        from_result(|| {
+            // SAFETY: This callback is called only in contexts
+            // where we can exclusively access `phy_device` because
+            // it's not published yet, so the accessors on `Device` are okay
+            // to call.
+            let dev = unsafe { Device::from_raw(phydev) };
+            T::probe(dev)?;
+            Ok(0)
+        })
+    }
+
+    /// # Safety
+    ///
+    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
     unsafe extern "C" fn get_features_callback(
         phydev: *mut bindings::phy_device,
     ) -> core::ffi::c_int {
@@ -491,7 +493,7 @@ impl<T: Driver> Adapter<T> {
 pub struct DriverVTable(Opaque<bindings::phy_driver>);
 
 // SAFETY: `DriverVTable` doesn't expose any &self method to access internal data, so it's safe to
-// share `&DriverVTable` across execution context boundries.
+// share `&DriverVTable` across execution context boundaries.
 unsafe impl Sync for DriverVTable {}
 
 /// Creates a [`DriverVTable`] instance from [`Driver`].
@@ -511,6 +513,11 @@ pub const fn create_phy_driver<T: Driver>() -> DriverVTable {
         } else {
             None
         },
+        probe: if T::HAS_PROBE {
+            Some(Adapter::<T>::probe_callback)
+        } else {
+            None
+        },
         get_features: if T::HAS_GET_FEATURES {
             Some(Adapter::<T>::get_features_callback)
         } else {
@@ -583,6 +590,11 @@ pub trait Driver {
         kernel::build_error(VTABLE_DEFAULT_ERROR)
     }
 
+    /// Sets up device-specific structures during discovery.
+    fn probe(_dev: &mut Device) -> Result {
+        kernel::build_error(VTABLE_DEFAULT_ERROR)
+    }
+
     /// Probes the hardware to determine what abilities it has.
     fn get_features(_dev: &mut Device) -> Result {
         kernel::build_error(VTABLE_DEFAULT_ERROR)