The read_mmd and write_mmd callbacks hand the driver a `&mut Device`
whose SAFETY comment says PHYLIB holds `phy_device->lock`. It does not
have to: __phy_read_mmd() and __phy_write_mmd() call them with the MDIO
bus lock held but not necessarily `phy_device->lock`, e.g. from
phy_read_mmd() in a hwmon read. The register accessors on `Device` take
the bus lock again, so using them there would deadlock.
No Rust driver implements these callbacks, and none has since they were
added with the abstraction. Drop them until there is a user and a way to
express the MDIO bus lock context.
Signed-off-by: SeungJong Ha <redacted>
---
rust/kernel/net/phy.rs | 58 --------------------------------------------------
1 file changed, 58 deletions(-)
diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs
index c4e7b1d6c6f4..7ca3f2329e6a 100644
--- a/rust/kernel/net/phy.rs
+++ b/rust/kernel/net/phy.rs
@@ -417,44 +417,6 @@ impl<T: Driver> Adapter<T> {
T::match_phy_device(dev).into()
}
- /// # Safety
- ///
- /// `phydev` must be passed by the corresponding callback in `phy_driver`.
- unsafe extern "C" fn read_mmd_callback(
- phydev: *mut bindings::phy_device,
- devnum: i32,
- regnum: u16,
- ) -> i32 {
- from_result(|| {
- // SAFETY: This callback is called only in contexts
- // where we hold `phy_device->lock`, so the accessors on
- // `Device` are okay to call.
- let dev = unsafe { Device::from_raw(phydev) };
- // CAST: the C side verifies devnum < 32.
- let ret = T::read_mmd(dev, devnum as u8, regnum)?;
- Ok(ret.into())
- })
- }
-
- /// # Safety
- ///
- /// `phydev` must be passed by the corresponding callback in `phy_driver`.
- unsafe extern "C" fn write_mmd_callback(
- phydev: *mut bindings::phy_device,
- devnum: i32,
- regnum: u16,
- val: u16,
- ) -> i32 {
- from_result(|| {
- // SAFETY: This callback is called only in contexts
- // where we hold `phy_device->lock`, so the accessors on
- // `Device` are okay to call.
- let dev = unsafe { Device::from_raw(phydev) };
- T::write_mmd(dev, devnum as u8, regnum, val)?;
- Ok(0)
- })
- }
-
/// # Safety
///
/// `phydev` must be passed by the corresponding callback in `phy_driver`.@@ -536,16 +498,6 @@ pub const fn create_phy_driver<T: Driver>() -> DriverVTable {
} 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 {@@ -615,16 +567,6 @@ fn resume(_dev: &mut Device) -> Result {
build_error!(VTABLE_DEFAULT_ERROR)
}
- /// Overrides the default MMD read function for reading a MMD register.
- fn read_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16) -> Result<u16> {
- build_error!(VTABLE_DEFAULT_ERROR)
- }
-
- /// Overrides the default MMD write function for writing a MMD register.
- fn write_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16, _val: u16) -> Result {
- build_error!(VTABLE_DEFAULT_ERROR)
- }
-
/// Callback for notification of link change.
fn link_change_notify(_dev: &mut Device) {}
}
--
2.54.0