Linux Audio

Check our new training course

Loading...
v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2
  3// Copyright (C) 2023 FUJITA Tomonori <fujita.tomonori@gmail.com>
  4
  5//! Network PHY device.
  6//!
  7//! C headers: [`include/linux/phy.h`](../../../../../../../include/linux/phy.h).
  8
  9use crate::{bindings, error::*, prelude::*, str::CStr, types::Opaque};
 10
 11use core::marker::PhantomData;
 12
 13/// PHY state machine states.
 14///
 15/// Corresponds to the kernel's [`enum phy_state`].
 16///
 17/// Some of PHY drivers access to the state of PHY's software state machine.
 18///
 19/// [`enum phy_state`]: ../../../../../../../include/linux/phy.h
 20#[derive(PartialEq, Eq)]
 21pub enum DeviceState {
 22    /// PHY device and driver are not ready for anything.
 23    Down,
 24    /// PHY is ready to send and receive packets.
 25    Ready,
 26    /// PHY is up, but no polling or interrupts are done.
 27    Halted,
 28    /// PHY is up, but is in an error state.
 29    Error,
 30    /// PHY and attached device are ready to do work.
 31    Up,
 32    /// PHY is currently running.
 33    Running,
 34    /// PHY is up, but not currently plugged in.
 35    NoLink,
 36    /// PHY is performing a cable test.
 37    CableTest,
 38}
 39
 40/// A mode of Ethernet communication.
 41///
 42/// PHY drivers get duplex information from hardware and update the current state.
 43pub enum DuplexMode {
 44    /// PHY is in full-duplex mode.
 45    Full,
 46    /// PHY is in half-duplex mode.
 47    Half,
 48    /// PHY is in unknown duplex mode.
 49    Unknown,
 50}
 51
 52/// An instance of a PHY device.
 53///
 54/// Wraps the kernel's [`struct phy_device`].
 55///
 56/// A [`Device`] instance is created when a callback in [`Driver`] is executed. A PHY driver
 57/// executes [`Driver`]'s methods during the callback.
 58///
 59/// # Invariants
 60///
 61/// Referencing a `phy_device` using this struct asserts that you are in
 62/// a context where all methods defined on this struct are safe to call.
 63///
 64/// [`struct phy_device`]: ../../../../../../../include/linux/phy.h
 65// During the calls to most functions in [`Driver`], the C side (`PHYLIB`) holds a lock that is
 66// unique for every instance of [`Device`]. `PHYLIB` uses a different serialization technique for
 67// [`Driver::resume`] and [`Driver::suspend`]: `PHYLIB` updates `phy_device`'s state with
 68// the lock held, thus guaranteeing that [`Driver::resume`] has exclusive access to the instance.
 69// [`Driver::resume`] and [`Driver::suspend`] also are called where only one thread can access
 70// to the instance.
 71#[repr(transparent)]
 72pub struct Device(Opaque<bindings::phy_device>);
 73
 74impl Device {
 75    /// Creates a new [`Device`] instance from a raw pointer.
 76    ///
 77    /// # Safety
 78    ///
 79    /// For the duration of 'a, the pointer must point at a valid `phy_device`,
 80    /// and the caller must be in a context where all methods defined on this struct
 81    /// are safe to call.
 82    unsafe fn from_raw<'a>(ptr: *mut bindings::phy_device) -> &'a mut Self {
 83        // CAST: `Self` is a `repr(transparent)` wrapper around `bindings::phy_device`.
 84        let ptr = ptr.cast::<Self>();
 85        // SAFETY: by the function requirements the pointer is valid and we have unique access for
 86        // the duration of `'a`.
 87        unsafe { &mut *ptr }
 88    }
 89
 90    /// Gets the id of the PHY.
 91    pub fn phy_id(&self) -> u32 {
 92        let phydev = self.0.get();
 93        // SAFETY: The struct invariant ensures that we may access
 94        // this field without additional synchronization.
 95        unsafe { (*phydev).phy_id }
 96    }
 97
 98    /// Gets the state of PHY state machine states.
 99    pub fn state(&self) -> DeviceState {
100        let phydev = self.0.get();
101        // SAFETY: The struct invariant ensures that we may access
102        // this field without additional synchronization.
103        let state = unsafe { (*phydev).state };
104        // TODO: this conversion code will be replaced with automatically generated code by bindgen
105        // when it becomes possible.
106        match state {
107            bindings::phy_state_PHY_DOWN => DeviceState::Down,
108            bindings::phy_state_PHY_READY => DeviceState::Ready,
109            bindings::phy_state_PHY_HALTED => DeviceState::Halted,
110            bindings::phy_state_PHY_ERROR => DeviceState::Error,
111            bindings::phy_state_PHY_UP => DeviceState::Up,
112            bindings::phy_state_PHY_RUNNING => DeviceState::Running,
113            bindings::phy_state_PHY_NOLINK => DeviceState::NoLink,
114            bindings::phy_state_PHY_CABLETEST => DeviceState::CableTest,
115            _ => DeviceState::Error,
116        }
117    }
118
119    /// Gets the current link state.
120    ///
121    /// It returns true if the link is up.
122    pub fn is_link_up(&self) -> bool {
123        const LINK_IS_UP: u64 = 1;
124        // TODO: the code to access to the bit field will be replaced with automatically
125        // generated code by bindgen when it becomes possible.
126        // SAFETY: The struct invariant ensures that we may access
127        // this field without additional synchronization.
128        let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
129        bit_field.get(14, 1) == LINK_IS_UP
130    }
131
132    /// Gets the current auto-negotiation configuration.
133    ///
134    /// It returns true if auto-negotiation is enabled.
135    pub fn is_autoneg_enabled(&self) -> bool {
136        // TODO: the code to access to the bit field will be replaced with automatically
137        // generated code by bindgen when it becomes possible.
138        // SAFETY: The struct invariant ensures that we may access
139        // this field without additional synchronization.
140        let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
141        bit_field.get(13, 1) == bindings::AUTONEG_ENABLE as u64
142    }
143
144    /// Gets the current auto-negotiation state.
145    ///
146    /// It returns true if auto-negotiation is completed.
147    pub fn is_autoneg_completed(&self) -> bool {
148        const AUTONEG_COMPLETED: u64 = 1;
149        // TODO: the code to access to the bit field will be replaced with automatically
150        // generated code by bindgen when it becomes possible.
151        // SAFETY: The struct invariant ensures that we may access
152        // this field without additional synchronization.
153        let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
154        bit_field.get(15, 1) == AUTONEG_COMPLETED
155    }
156
157    /// Sets the speed of the PHY.
158    pub fn set_speed(&mut self, speed: u32) {
159        let phydev = self.0.get();
160        // SAFETY: The struct invariant ensures that we may access
161        // this field without additional synchronization.
162        unsafe { (*phydev).speed = speed as i32 };
163    }
164
165    /// Sets duplex mode.
166    pub fn set_duplex(&mut self, mode: DuplexMode) {
167        let phydev = self.0.get();
168        let v = match mode {
169            DuplexMode::Full => bindings::DUPLEX_FULL as i32,
170            DuplexMode::Half => bindings::DUPLEX_HALF as i32,
171            DuplexMode::Unknown => bindings::DUPLEX_UNKNOWN as i32,
172        };
173        // SAFETY: The struct invariant ensures that we may access
174        // this field without additional synchronization.
175        unsafe { (*phydev).duplex = v };
176    }
177
178    /// Reads a given C22 PHY register.
179    // This function reads a hardware register and updates the stats so takes `&mut self`.
180    pub fn read(&mut self, regnum: u16) -> Result<u16> {
181        let phydev = self.0.get();
182        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
183        // So it's just an FFI call, open code of `phy_read()` with a valid `phy_device` pointer
184        // `phydev`.
185        let ret = unsafe {
186            bindings::mdiobus_read((*phydev).mdio.bus, (*phydev).mdio.addr, regnum.into())
187        };
188        if ret < 0 {
189            Err(Error::from_errno(ret))
190        } else {
191            Ok(ret as u16)
192        }
193    }
194
195    /// Writes a given C22 PHY register.
196    pub fn write(&mut self, regnum: u16, val: u16) -> Result {
197        let phydev = self.0.get();
198        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
199        // So it's just an FFI call, open code of `phy_write()` with a valid `phy_device` pointer
200        // `phydev`.
201        to_result(unsafe {
202            bindings::mdiobus_write((*phydev).mdio.bus, (*phydev).mdio.addr, regnum.into(), val)
203        })
204    }
205
206    /// Reads a paged register.
207    pub fn read_paged(&mut self, page: u16, regnum: u16) -> Result<u16> {
208        let phydev = self.0.get();
209        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
210        // So it's just an FFI call.
211        let ret = unsafe { bindings::phy_read_paged(phydev, page.into(), regnum.into()) };
212        if ret < 0 {
213            Err(Error::from_errno(ret))
214        } else {
215            Ok(ret as u16)
216        }
217    }
218
219    /// Resolves the advertisements into PHY settings.
220    pub fn resolve_aneg_linkmode(&mut self) {
221        let phydev = self.0.get();
222        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
223        // So it's just an FFI call.
224        unsafe { bindings::phy_resolve_aneg_linkmode(phydev) };
225    }
226
227    /// Executes software reset the PHY via `BMCR_RESET` bit.
228    pub fn genphy_soft_reset(&mut self) -> Result {
229        let phydev = self.0.get();
230        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
231        // So it's just an FFI call.
232        to_result(unsafe { bindings::genphy_soft_reset(phydev) })
233    }
234
235    /// Initializes the PHY.
236    pub fn init_hw(&mut self) -> Result {
237        let phydev = self.0.get();
238        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
239        // So it's just an FFI call.
240        to_result(unsafe { bindings::phy_init_hw(phydev) })
241    }
242
243    /// Starts auto-negotiation.
244    pub fn start_aneg(&mut self) -> Result {
245        let phydev = self.0.get();
246        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
247        // So it's just an FFI call.
248        to_result(unsafe { bindings::_phy_start_aneg(phydev) })
249    }
250
251    /// Resumes the PHY via `BMCR_PDOWN` bit.
252    pub fn genphy_resume(&mut self) -> Result {
253        let phydev = self.0.get();
254        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
255        // So it's just an FFI call.
256        to_result(unsafe { bindings::genphy_resume(phydev) })
257    }
258
259    /// Suspends the PHY via `BMCR_PDOWN` bit.
260    pub fn genphy_suspend(&mut self) -> Result {
261        let phydev = self.0.get();
262        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
263        // So it's just an FFI call.
264        to_result(unsafe { bindings::genphy_suspend(phydev) })
265    }
266
267    /// Checks the link status and updates current link state.
268    pub fn genphy_read_status(&mut self) -> Result<u16> {
269        let phydev = self.0.get();
270        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
271        // So it's just an FFI call.
272        let ret = unsafe { bindings::genphy_read_status(phydev) };
273        if ret < 0 {
274            Err(Error::from_errno(ret))
275        } else {
276            Ok(ret as u16)
277        }
278    }
279
280    /// Updates the link status.
281    pub fn genphy_update_link(&mut self) -> Result {
282        let phydev = self.0.get();
283        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
284        // So it's just an FFI call.
285        to_result(unsafe { bindings::genphy_update_link(phydev) })
286    }
287
288    /// Reads link partner ability.
289    pub fn genphy_read_lpa(&mut self) -> Result {
290        let phydev = self.0.get();
291        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
292        // So it's just an FFI call.
293        to_result(unsafe { bindings::genphy_read_lpa(phydev) })
294    }
295
296    /// Reads PHY abilities.
297    pub fn genphy_read_abilities(&mut self) -> Result {
298        let phydev = self.0.get();
299        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
300        // So it's just an FFI call.
301        to_result(unsafe { bindings::genphy_read_abilities(phydev) })
302    }
303}
304
305/// Defines certain other features this PHY supports (like interrupts).
306///
307/// These flag values are used in [`Driver::FLAGS`].
308pub mod flags {
309    /// PHY is internal.
310    pub const IS_INTERNAL: u32 = bindings::PHY_IS_INTERNAL;
311    /// PHY needs to be reset after the refclk is enabled.
312    pub const RST_AFTER_CLK_EN: u32 = bindings::PHY_RST_AFTER_CLK_EN;
313    /// Polling is used to detect PHY status changes.
314    pub const POLL_CABLE_TEST: u32 = bindings::PHY_POLL_CABLE_TEST;
315    /// Don't suspend.
316    pub const ALWAYS_CALL_SUSPEND: u32 = bindings::PHY_ALWAYS_CALL_SUSPEND;
317}
318
319/// An adapter for the registration of a PHY driver.
320struct Adapter<T: Driver> {
321    _p: PhantomData<T>,
322}
323
324impl<T: Driver> Adapter<T> {
325    /// # Safety
326    ///
327    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
328    unsafe extern "C" fn soft_reset_callback(
329        phydev: *mut bindings::phy_device,
330    ) -> core::ffi::c_int {
331        from_result(|| {
332            // SAFETY: This callback is called only in contexts
333            // where we hold `phy_device->lock`, so the accessors on
334            // `Device` are okay to call.
335            let dev = unsafe { Device::from_raw(phydev) };
336            T::soft_reset(dev)?;
337            Ok(0)
338        })
339    }
340
341    /// # Safety
342    ///
343    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
344    unsafe extern "C" fn get_features_callback(
345        phydev: *mut bindings::phy_device,
346    ) -> core::ffi::c_int {
347        from_result(|| {
348            // SAFETY: This callback is called only in contexts
349            // where we hold `phy_device->lock`, so the accessors on
350            // `Device` are okay to call.
351            let dev = unsafe { Device::from_raw(phydev) };
352            T::get_features(dev)?;
353            Ok(0)
354        })
355    }
356
357    /// # Safety
358    ///
359    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
360    unsafe extern "C" fn suspend_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int {
361        from_result(|| {
362            // SAFETY: The C core code ensures that the accessors on
363            // `Device` are okay to call even though `phy_device->lock`
364            // might not be held.
365            let dev = unsafe { Device::from_raw(phydev) };
366            T::suspend(dev)?;
367            Ok(0)
368        })
369    }
370
371    /// # Safety
372    ///
373    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
374    unsafe extern "C" fn resume_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int {
375        from_result(|| {
376            // SAFETY: The C core code ensures that the accessors on
377            // `Device` are okay to call even though `phy_device->lock`
378            // might not be held.
379            let dev = unsafe { Device::from_raw(phydev) };
380            T::resume(dev)?;
381            Ok(0)
382        })
383    }
384
385    /// # Safety
386    ///
387    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
388    unsafe extern "C" fn config_aneg_callback(
389        phydev: *mut bindings::phy_device,
390    ) -> core::ffi::c_int {
391        from_result(|| {
392            // SAFETY: This callback is called only in contexts
393            // where we hold `phy_device->lock`, so the accessors on
394            // `Device` are okay to call.
395            let dev = unsafe { Device::from_raw(phydev) };
396            T::config_aneg(dev)?;
397            Ok(0)
398        })
399    }
400
401    /// # Safety
402    ///
403    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
404    unsafe extern "C" fn read_status_callback(
405        phydev: *mut bindings::phy_device,
406    ) -> core::ffi::c_int {
407        from_result(|| {
408            // SAFETY: This callback is called only in contexts
409            // where we hold `phy_device->lock`, so the accessors on
410            // `Device` are okay to call.
411            let dev = unsafe { Device::from_raw(phydev) };
412            T::read_status(dev)?;
413            Ok(0)
414        })
415    }
416
417    /// # Safety
418    ///
419    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
420    unsafe extern "C" fn match_phy_device_callback(
421        phydev: *mut bindings::phy_device,
422    ) -> core::ffi::c_int {
423        // SAFETY: This callback is called only in contexts
424        // where we hold `phy_device->lock`, so the accessors on
425        // `Device` are okay to call.
426        let dev = unsafe { Device::from_raw(phydev) };
427        T::match_phy_device(dev) as i32
428    }
429
430    /// # Safety
431    ///
432    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
433    unsafe extern "C" fn read_mmd_callback(
434        phydev: *mut bindings::phy_device,
435        devnum: i32,
436        regnum: u16,
437    ) -> i32 {
438        from_result(|| {
439            // SAFETY: This callback is called only in contexts
440            // where we hold `phy_device->lock`, so the accessors on
441            // `Device` are okay to call.
442            let dev = unsafe { Device::from_raw(phydev) };
443            // CAST: the C side verifies devnum < 32.
444            let ret = T::read_mmd(dev, devnum as u8, regnum)?;
445            Ok(ret.into())
446        })
447    }
448
449    /// # Safety
450    ///
451    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
452    unsafe extern "C" fn write_mmd_callback(
453        phydev: *mut bindings::phy_device,
454        devnum: i32,
455        regnum: u16,
456        val: u16,
457    ) -> i32 {
458        from_result(|| {
459            // SAFETY: This callback is called only in contexts
460            // where we hold `phy_device->lock`, so the accessors on
461            // `Device` are okay to call.
462            let dev = unsafe { Device::from_raw(phydev) };
463            T::write_mmd(dev, devnum as u8, regnum, val)?;
464            Ok(0)
465        })
466    }
467
468    /// # Safety
469    ///
470    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
471    unsafe extern "C" fn link_change_notify_callback(phydev: *mut bindings::phy_device) {
472        // SAFETY: This callback is called only in contexts
473        // where we hold `phy_device->lock`, so the accessors on
474        // `Device` are okay to call.
475        let dev = unsafe { Device::from_raw(phydev) };
476        T::link_change_notify(dev);
477    }
478}
479
480/// Driver structure for a particular PHY type.
481///
482/// Wraps the kernel's [`struct phy_driver`].
483/// This is used to register a driver for a particular PHY type with the kernel.
484///
485/// # Invariants
486///
487/// `self.0` is always in a valid state.
488///
489/// [`struct phy_driver`]: ../../../../../../../include/linux/phy.h
490#[repr(transparent)]
491pub struct DriverVTable(Opaque<bindings::phy_driver>);
492
493// SAFETY: `DriverVTable` doesn't expose any &self method to access internal data, so it's safe to
494// share `&DriverVTable` across execution context boundries.
495unsafe impl Sync for DriverVTable {}
496
497/// Creates a [`DriverVTable`] instance from [`Driver`].
498///
499/// This is used by [`module_phy_driver`] macro to create a static array of `phy_driver`.
500///
501/// [`module_phy_driver`]: crate::module_phy_driver
502pub const fn create_phy_driver<T: Driver>() -> DriverVTable {
503    // INVARIANT: All the fields of `struct phy_driver` are initialized properly.
504    DriverVTable(Opaque::new(bindings::phy_driver {
505        name: T::NAME.as_char_ptr().cast_mut(),
506        flags: T::FLAGS,
507        phy_id: T::PHY_DEVICE_ID.id,
508        phy_id_mask: T::PHY_DEVICE_ID.mask_as_int(),
509        soft_reset: if T::HAS_SOFT_RESET {
510            Some(Adapter::<T>::soft_reset_callback)
511        } else {
512            None
513        },
514        get_features: if T::HAS_GET_FEATURES {
515            Some(Adapter::<T>::get_features_callback)
516        } else {
517            None
518        },
519        match_phy_device: if T::HAS_MATCH_PHY_DEVICE {
520            Some(Adapter::<T>::match_phy_device_callback)
521        } else {
522            None
523        },
524        suspend: if T::HAS_SUSPEND {
525            Some(Adapter::<T>::suspend_callback)
526        } else {
527            None
528        },
529        resume: if T::HAS_RESUME {
530            Some(Adapter::<T>::resume_callback)
531        } else {
532            None
533        },
534        config_aneg: if T::HAS_CONFIG_ANEG {
535            Some(Adapter::<T>::config_aneg_callback)
536        } else {
537            None
538        },
539        read_status: if T::HAS_READ_STATUS {
540            Some(Adapter::<T>::read_status_callback)
541        } else {
542            None
543        },
544        read_mmd: if T::HAS_READ_MMD {
545            Some(Adapter::<T>::read_mmd_callback)
546        } else {
547            None
548        },
549        write_mmd: if T::HAS_WRITE_MMD {
550            Some(Adapter::<T>::write_mmd_callback)
551        } else {
552            None
553        },
554        link_change_notify: if T::HAS_LINK_CHANGE_NOTIFY {
555            Some(Adapter::<T>::link_change_notify_callback)
556        } else {
557            None
558        },
559        // SAFETY: The rest is zeroed out to initialize `struct phy_driver`,
560        // sets `Option<&F>` to be `None`.
561        ..unsafe { core::mem::MaybeUninit::<bindings::phy_driver>::zeroed().assume_init() }
562    }))
563}
564
565/// Driver implementation for a particular PHY type.
566///
567/// This trait is used to create a [`DriverVTable`].
568#[vtable]
569pub trait Driver {
570    /// Defines certain other features this PHY supports.
571    /// It is a combination of the flags in the [`flags`] module.
572    const FLAGS: u32 = 0;
573
574    /// The friendly name of this PHY type.
575    const NAME: &'static CStr;
576
577    /// This driver only works for PHYs with IDs which match this field.
578    /// The default id and mask are zero.
579    const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_custom_mask(0, 0);
580
581    /// Issues a PHY software reset.
582    fn soft_reset(_dev: &mut Device) -> Result {
583        Err(code::ENOTSUPP)
584    }
585
586    /// Probes the hardware to determine what abilities it has.
587    fn get_features(_dev: &mut Device) -> Result {
588        Err(code::ENOTSUPP)
589    }
590
591    /// Returns true if this is a suitable driver for the given phydev.
592    /// If not implemented, matching is based on [`Driver::PHY_DEVICE_ID`].
593    fn match_phy_device(_dev: &Device) -> bool {
594        false
595    }
596
597    /// Configures the advertisement and resets auto-negotiation
598    /// if auto-negotiation is enabled.
599    fn config_aneg(_dev: &mut Device) -> Result {
600        Err(code::ENOTSUPP)
601    }
602
603    /// Determines the negotiated speed and duplex.
604    fn read_status(_dev: &mut Device) -> Result<u16> {
605        Err(code::ENOTSUPP)
606    }
607
608    /// Suspends the hardware, saving state if needed.
609    fn suspend(_dev: &mut Device) -> Result {
610        Err(code::ENOTSUPP)
611    }
612
613    /// Resumes the hardware, restoring state if needed.
614    fn resume(_dev: &mut Device) -> Result {
615        Err(code::ENOTSUPP)
616    }
617
618    /// Overrides the default MMD read function for reading a MMD register.
619    fn read_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16) -> Result<u16> {
620        Err(code::ENOTSUPP)
621    }
622
623    /// Overrides the default MMD write function for writing a MMD register.
624    fn write_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16, _val: u16) -> Result {
625        Err(code::ENOTSUPP)
626    }
627
628    /// Callback for notification of link change.
629    fn link_change_notify(_dev: &mut Device) {}
630}
631
632/// Registration structure for PHY drivers.
633///
634/// Registers [`DriverVTable`] instances with the kernel. They will be unregistered when dropped.
635///
636/// # Invariants
637///
638/// The `drivers` slice are currently registered to the kernel via `phy_drivers_register`.
639pub struct Registration {
640    drivers: Pin<&'static mut [DriverVTable]>,
641}
 
 
 
 
642
643impl Registration {
644    /// Registers a PHY driver.
645    pub fn register(
646        module: &'static crate::ThisModule,
647        drivers: Pin<&'static mut [DriverVTable]>,
648    ) -> Result<Self> {
649        if drivers.is_empty() {
650            return Err(code::EINVAL);
651        }
652        // SAFETY: The type invariants of [`DriverVTable`] ensure that all elements of
653        // the `drivers` slice are initialized properly. `drivers` will not be moved.
654        // So it's just an FFI call.
655        to_result(unsafe {
656            bindings::phy_drivers_register(drivers[0].0.get(), drivers.len().try_into()?, module.0)
657        })?;
658        // INVARIANT: The `drivers` slice is successfully registered to the kernel via `phy_drivers_register`.
659        Ok(Registration { drivers })
660    }
661}
662
663impl Drop for Registration {
664    fn drop(&mut self) {
665        // SAFETY: The type invariants guarantee that `self.drivers` is valid.
666        // So it's just an FFI call.
667        unsafe {
668            bindings::phy_drivers_unregister(self.drivers[0].0.get(), self.drivers.len() as i32)
669        };
670    }
671}
672
673/// An identifier for PHY devices on an MDIO/MII bus.
674///
675/// Represents the kernel's `struct mdio_device_id`. This is used to find an appropriate
676/// PHY driver.
677pub struct DeviceId {
678    id: u32,
679    mask: DeviceMask,
680}
681
682impl DeviceId {
683    /// Creates a new instance with the exact match mask.
684    pub const fn new_with_exact_mask(id: u32) -> Self {
685        DeviceId {
686            id,
687            mask: DeviceMask::Exact,
688        }
689    }
690
691    /// Creates a new instance with the model match mask.
692    pub const fn new_with_model_mask(id: u32) -> Self {
693        DeviceId {
694            id,
695            mask: DeviceMask::Model,
696        }
697    }
698
699    /// Creates a new instance with the vendor match mask.
700    pub const fn new_with_vendor_mask(id: u32) -> Self {
701        DeviceId {
702            id,
703            mask: DeviceMask::Vendor,
704        }
705    }
706
707    /// Creates a new instance with a custom match mask.
708    pub const fn new_with_custom_mask(id: u32, mask: u32) -> Self {
709        DeviceId {
710            id,
711            mask: DeviceMask::Custom(mask),
712        }
713    }
714
715    /// Creates a new instance from [`Driver`].
716    pub const fn new_with_driver<T: Driver>() -> Self {
717        T::PHY_DEVICE_ID
718    }
719
720    /// Get a `mask` as u32.
721    pub const fn mask_as_int(&self) -> u32 {
722        self.mask.as_int()
723    }
724
725    // macro use only
726    #[doc(hidden)]
727    pub const fn mdio_device_id(&self) -> bindings::mdio_device_id {
728        bindings::mdio_device_id {
729            phy_id: self.id,
730            phy_id_mask: self.mask.as_int(),
731        }
732    }
733}
734
735enum DeviceMask {
736    Exact,
737    Model,
738    Vendor,
739    Custom(u32),
740}
741
742impl DeviceMask {
743    const MASK_EXACT: u32 = !0;
744    const MASK_MODEL: u32 = !0 << 4;
745    const MASK_VENDOR: u32 = !0 << 10;
746
747    const fn as_int(&self) -> u32 {
748        match self {
749            DeviceMask::Exact => Self::MASK_EXACT,
750            DeviceMask::Model => Self::MASK_MODEL,
751            DeviceMask::Vendor => Self::MASK_VENDOR,
752            DeviceMask::Custom(mask) => *mask,
753        }
754    }
755}
756
757/// Declares a kernel module for PHYs drivers.
758///
759/// This creates a static array of kernel's `struct phy_driver` and registers it.
760/// This also corresponds to the kernel's `MODULE_DEVICE_TABLE` macro, which embeds the information
761/// for module loading into the module binary file. Every driver needs an entry in `device_table`.
762///
763/// # Examples
764///
765/// ```
766/// # mod module_phy_driver_sample {
767/// use kernel::c_str;
768/// use kernel::net::phy::{self, DeviceId};
769/// use kernel::prelude::*;
770///
771/// kernel::module_phy_driver! {
772///     drivers: [PhySample],
773///     device_table: [
774///         DeviceId::new_with_driver::<PhySample>()
775///     ],
776///     name: "rust_sample_phy",
777///     author: "Rust for Linux Contributors",
778///     description: "Rust sample PHYs driver",
779///     license: "GPL",
780/// }
781///
782/// struct PhySample;
783///
784/// #[vtable]
785/// impl phy::Driver for PhySample {
786///     const NAME: &'static CStr = c_str!("PhySample");
787///     const PHY_DEVICE_ID: phy::DeviceId = phy::DeviceId::new_with_exact_mask(0x00000001);
788/// }
789/// # }
790/// ```
791///
792/// This expands to the following code:
793///
794/// ```ignore
795/// use kernel::c_str;
796/// use kernel::net::phy::{self, DeviceId};
797/// use kernel::prelude::*;
798///
799/// struct Module {
800///     _reg: ::kernel::net::phy::Registration,
801/// }
802///
803/// module! {
804///     type: Module,
805///     name: "rust_sample_phy",
806///     author: "Rust for Linux Contributors",
807///     description: "Rust sample PHYs driver",
808///     license: "GPL",
809/// }
810///
811/// struct PhySample;
812///
813/// #[vtable]
814/// impl phy::Driver for PhySample {
815///     const NAME: &'static CStr = c_str!("PhySample");
816///     const PHY_DEVICE_ID: phy::DeviceId = phy::DeviceId::new_with_exact_mask(0x00000001);
817/// }
818///
819/// const _: () = {
820///     static mut DRIVERS: [::kernel::net::phy::DriverVTable; 1] =
821///         [::kernel::net::phy::create_phy_driver::<PhySample>()];
822///
823///     impl ::kernel::Module for Module {
824///         fn init(module: &'static ThisModule) -> Result<Self> {
825///             let drivers = unsafe { &mut DRIVERS };
826///             let mut reg = ::kernel::net::phy::Registration::register(
827///                 module,
828///                 ::core::pin::Pin::static_mut(drivers),
829///             )?;
830///             Ok(Module { _reg: reg })
831///         }
832///     }
833/// };
834///
835/// #[cfg(MODULE)]
836/// #[no_mangle]
837/// static __mod_mdio__phydev_device_table: [::kernel::bindings::mdio_device_id; 2] = [
838///     ::kernel::bindings::mdio_device_id {
839///         phy_id: 0x00000001,
840///         phy_id_mask: 0xffffffff,
841///     },
842///     ::kernel::bindings::mdio_device_id {
843///         phy_id: 0,
844///         phy_id_mask: 0,
845///     },
846/// ];
847/// ```
848#[macro_export]
849macro_rules! module_phy_driver {
850    (@replace_expr $_t:tt $sub:expr) => {$sub};
851
852    (@count_devices $($x:expr),*) => {
853        0usize $(+ $crate::module_phy_driver!(@replace_expr $x 1usize))*
854    };
855
856    (@device_table [$($dev:expr),+]) => {
857        // SAFETY: C will not read off the end of this constant since the last element is zero.
858        #[cfg(MODULE)]
859        #[no_mangle]
860        static __mod_mdio__phydev_device_table: [$crate::bindings::mdio_device_id;
861            $crate::module_phy_driver!(@count_devices $($dev),+) + 1] = [
862            $($dev.mdio_device_id()),+,
863            $crate::bindings::mdio_device_id {
864                phy_id: 0,
865                phy_id_mask: 0
866            }
867        ];
868    };
869
870    (drivers: [$($driver:ident),+ $(,)?], device_table: [$($dev:expr),+ $(,)?], $($f:tt)*) => {
871        struct Module {
872            _reg: $crate::net::phy::Registration,
873        }
874
875        $crate::prelude::module! {
876            type: Module,
877            $($f)*
878        }
879
880        const _: () = {
881            static mut DRIVERS: [$crate::net::phy::DriverVTable;
882                $crate::module_phy_driver!(@count_devices $($driver),+)] =
883                [$($crate::net::phy::create_phy_driver::<$driver>()),+];
884
885            impl $crate::Module for Module {
886                fn init(module: &'static ThisModule) -> Result<Self> {
887                    // SAFETY: The anonymous constant guarantees that nobody else can access
888                    // the `DRIVERS` static. The array is used only in the C side.
889                    let drivers = unsafe { &mut DRIVERS };
890                    let mut reg = $crate::net::phy::Registration::register(
891                        module,
892                        ::core::pin::Pin::static_mut(drivers),
893                    )?;
894                    Ok(Module { _reg: reg })
895                }
896            }
897        };
898
899        $crate::module_phy_driver!(@device_table [$($dev),+]);
900    }
901}
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0
  2
  3// Copyright (C) 2023 FUJITA Tomonori <fujita.tomonori@gmail.com>
  4
  5//! Network PHY device.
  6//!
  7//! C headers: [`include/linux/phy.h`](srctree/include/linux/phy.h).
  8
  9use crate::{bindings, error::*, prelude::*, str::CStr, types::Opaque};
 10
 11use core::marker::PhantomData;
 12
 13/// PHY state machine states.
 14///
 15/// Corresponds to the kernel's [`enum phy_state`].
 16///
 17/// Some of PHY drivers access to the state of PHY's software state machine.
 18///
 19/// [`enum phy_state`]: srctree/include/linux/phy.h
 20#[derive(PartialEq, Eq)]
 21pub enum DeviceState {
 22    /// PHY device and driver are not ready for anything.
 23    Down,
 24    /// PHY is ready to send and receive packets.
 25    Ready,
 26    /// PHY is up, but no polling or interrupts are done.
 27    Halted,
 28    /// PHY is up, but is in an error state.
 29    Error,
 30    /// PHY and attached device are ready to do work.
 31    Up,
 32    /// PHY is currently running.
 33    Running,
 34    /// PHY is up, but not currently plugged in.
 35    NoLink,
 36    /// PHY is performing a cable test.
 37    CableTest,
 38}
 39
 40/// A mode of Ethernet communication.
 41///
 42/// PHY drivers get duplex information from hardware and update the current state.
 43pub enum DuplexMode {
 44    /// PHY is in full-duplex mode.
 45    Full,
 46    /// PHY is in half-duplex mode.
 47    Half,
 48    /// PHY is in unknown duplex mode.
 49    Unknown,
 50}
 51
 52/// An instance of a PHY device.
 53///
 54/// Wraps the kernel's [`struct phy_device`].
 55///
 56/// A [`Device`] instance is created when a callback in [`Driver`] is executed. A PHY driver
 57/// executes [`Driver`]'s methods during the callback.
 58///
 59/// # Invariants
 60///
 61/// Referencing a `phy_device` using this struct asserts that you are in
 62/// a context where all methods defined on this struct are safe to call.
 63///
 64/// [`struct phy_device`]: srctree/include/linux/phy.h
 65// During the calls to most functions in [`Driver`], the C side (`PHYLIB`) holds a lock that is
 66// unique for every instance of [`Device`]. `PHYLIB` uses a different serialization technique for
 67// [`Driver::resume`] and [`Driver::suspend`]: `PHYLIB` updates `phy_device`'s state with
 68// the lock held, thus guaranteeing that [`Driver::resume`] has exclusive access to the instance.
 69// [`Driver::resume`] and [`Driver::suspend`] also are called where only one thread can access
 70// to the instance.
 71#[repr(transparent)]
 72pub struct Device(Opaque<bindings::phy_device>);
 73
 74impl Device {
 75    /// Creates a new [`Device`] instance from a raw pointer.
 76    ///
 77    /// # Safety
 78    ///
 79    /// For the duration of 'a, the pointer must point at a valid `phy_device`,
 80    /// and the caller must be in a context where all methods defined on this struct
 81    /// are safe to call.
 82    unsafe fn from_raw<'a>(ptr: *mut bindings::phy_device) -> &'a mut Self {
 83        // CAST: `Self` is a `repr(transparent)` wrapper around `bindings::phy_device`.
 84        let ptr = ptr.cast::<Self>();
 85        // SAFETY: by the function requirements the pointer is valid and we have unique access for
 86        // the duration of `'a`.
 87        unsafe { &mut *ptr }
 88    }
 89
 90    /// Gets the id of the PHY.
 91    pub fn phy_id(&self) -> u32 {
 92        let phydev = self.0.get();
 93        // SAFETY: The struct invariant ensures that we may access
 94        // this field without additional synchronization.
 95        unsafe { (*phydev).phy_id }
 96    }
 97
 98    /// Gets the state of PHY state machine states.
 99    pub fn state(&self) -> DeviceState {
100        let phydev = self.0.get();
101        // SAFETY: The struct invariant ensures that we may access
102        // this field without additional synchronization.
103        let state = unsafe { (*phydev).state };
104        // TODO: this conversion code will be replaced with automatically generated code by bindgen
105        // when it becomes possible.
106        match state {
107            bindings::phy_state_PHY_DOWN => DeviceState::Down,
108            bindings::phy_state_PHY_READY => DeviceState::Ready,
109            bindings::phy_state_PHY_HALTED => DeviceState::Halted,
110            bindings::phy_state_PHY_ERROR => DeviceState::Error,
111            bindings::phy_state_PHY_UP => DeviceState::Up,
112            bindings::phy_state_PHY_RUNNING => DeviceState::Running,
113            bindings::phy_state_PHY_NOLINK => DeviceState::NoLink,
114            bindings::phy_state_PHY_CABLETEST => DeviceState::CableTest,
115            _ => DeviceState::Error,
116        }
117    }
118
119    /// Gets the current link state.
120    ///
121    /// It returns true if the link is up.
122    pub fn is_link_up(&self) -> bool {
123        const LINK_IS_UP: u64 = 1;
124        // TODO: the code to access to the bit field will be replaced with automatically
125        // generated code by bindgen when it becomes possible.
126        // SAFETY: The struct invariant ensures that we may access
127        // this field without additional synchronization.
128        let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
129        bit_field.get(14, 1) == LINK_IS_UP
130    }
131
132    /// Gets the current auto-negotiation configuration.
133    ///
134    /// It returns true if auto-negotiation is enabled.
135    pub fn is_autoneg_enabled(&self) -> bool {
136        // TODO: the code to access to the bit field will be replaced with automatically
137        // generated code by bindgen when it becomes possible.
138        // SAFETY: The struct invariant ensures that we may access
139        // this field without additional synchronization.
140        let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
141        bit_field.get(13, 1) == bindings::AUTONEG_ENABLE as u64
142    }
143
144    /// Gets the current auto-negotiation state.
145    ///
146    /// It returns true if auto-negotiation is completed.
147    pub fn is_autoneg_completed(&self) -> bool {
148        const AUTONEG_COMPLETED: u64 = 1;
149        // TODO: the code to access to the bit field will be replaced with automatically
150        // generated code by bindgen when it becomes possible.
151        // SAFETY: The struct invariant ensures that we may access
152        // this field without additional synchronization.
153        let bit_field = unsafe { &(*self.0.get())._bitfield_1 };
154        bit_field.get(15, 1) == AUTONEG_COMPLETED
155    }
156
157    /// Sets the speed of the PHY.
158    pub fn set_speed(&mut self, speed: u32) {
159        let phydev = self.0.get();
160        // SAFETY: The struct invariant ensures that we may access
161        // this field without additional synchronization.
162        unsafe { (*phydev).speed = speed as i32 };
163    }
164
165    /// Sets duplex mode.
166    pub fn set_duplex(&mut self, mode: DuplexMode) {
167        let phydev = self.0.get();
168        let v = match mode {
169            DuplexMode::Full => bindings::DUPLEX_FULL as i32,
170            DuplexMode::Half => bindings::DUPLEX_HALF as i32,
171            DuplexMode::Unknown => bindings::DUPLEX_UNKNOWN as i32,
172        };
173        // SAFETY: The struct invariant ensures that we may access
174        // this field without additional synchronization.
175        unsafe { (*phydev).duplex = v };
176    }
177
178    /// Reads a given C22 PHY register.
179    // This function reads a hardware register and updates the stats so takes `&mut self`.
180    pub fn read(&mut self, regnum: u16) -> Result<u16> {
181        let phydev = self.0.get();
182        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
183        // So it's just an FFI call, open code of `phy_read()` with a valid `phy_device` pointer
184        // `phydev`.
185        let ret = unsafe {
186            bindings::mdiobus_read((*phydev).mdio.bus, (*phydev).mdio.addr, regnum.into())
187        };
188        if ret < 0 {
189            Err(Error::from_errno(ret))
190        } else {
191            Ok(ret as u16)
192        }
193    }
194
195    /// Writes a given C22 PHY register.
196    pub fn write(&mut self, regnum: u16, val: u16) -> Result {
197        let phydev = self.0.get();
198        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
199        // So it's just an FFI call, open code of `phy_write()` with a valid `phy_device` pointer
200        // `phydev`.
201        to_result(unsafe {
202            bindings::mdiobus_write((*phydev).mdio.bus, (*phydev).mdio.addr, regnum.into(), val)
203        })
204    }
205
206    /// Reads a paged register.
207    pub fn read_paged(&mut self, page: u16, regnum: u16) -> Result<u16> {
208        let phydev = self.0.get();
209        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
210        // So it's just an FFI call.
211        let ret = unsafe { bindings::phy_read_paged(phydev, page.into(), regnum.into()) };
212        if ret < 0 {
213            Err(Error::from_errno(ret))
214        } else {
215            Ok(ret as u16)
216        }
217    }
218
219    /// Resolves the advertisements into PHY settings.
220    pub fn resolve_aneg_linkmode(&mut self) {
221        let phydev = self.0.get();
222        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
223        // So it's just an FFI call.
224        unsafe { bindings::phy_resolve_aneg_linkmode(phydev) };
225    }
226
227    /// Executes software reset the PHY via `BMCR_RESET` bit.
228    pub fn genphy_soft_reset(&mut self) -> Result {
229        let phydev = self.0.get();
230        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
231        // So it's just an FFI call.
232        to_result(unsafe { bindings::genphy_soft_reset(phydev) })
233    }
234
235    /// Initializes the PHY.
236    pub fn init_hw(&mut self) -> Result {
237        let phydev = self.0.get();
238        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
239        // So it's just an FFI call.
240        to_result(unsafe { bindings::phy_init_hw(phydev) })
241    }
242
243    /// Starts auto-negotiation.
244    pub fn start_aneg(&mut self) -> Result {
245        let phydev = self.0.get();
246        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
247        // So it's just an FFI call.
248        to_result(unsafe { bindings::_phy_start_aneg(phydev) })
249    }
250
251    /// Resumes the PHY via `BMCR_PDOWN` bit.
252    pub fn genphy_resume(&mut self) -> Result {
253        let phydev = self.0.get();
254        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
255        // So it's just an FFI call.
256        to_result(unsafe { bindings::genphy_resume(phydev) })
257    }
258
259    /// Suspends the PHY via `BMCR_PDOWN` bit.
260    pub fn genphy_suspend(&mut self) -> Result {
261        let phydev = self.0.get();
262        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
263        // So it's just an FFI call.
264        to_result(unsafe { bindings::genphy_suspend(phydev) })
265    }
266
267    /// Checks the link status and updates current link state.
268    pub fn genphy_read_status(&mut self) -> Result<u16> {
269        let phydev = self.0.get();
270        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
271        // So it's just an FFI call.
272        let ret = unsafe { bindings::genphy_read_status(phydev) };
273        if ret < 0 {
274            Err(Error::from_errno(ret))
275        } else {
276            Ok(ret as u16)
277        }
278    }
279
280    /// Updates the link status.
281    pub fn genphy_update_link(&mut self) -> Result {
282        let phydev = self.0.get();
283        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
284        // So it's just an FFI call.
285        to_result(unsafe { bindings::genphy_update_link(phydev) })
286    }
287
288    /// Reads link partner ability.
289    pub fn genphy_read_lpa(&mut self) -> Result {
290        let phydev = self.0.get();
291        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
292        // So it's just an FFI call.
293        to_result(unsafe { bindings::genphy_read_lpa(phydev) })
294    }
295
296    /// Reads PHY abilities.
297    pub fn genphy_read_abilities(&mut self) -> Result {
298        let phydev = self.0.get();
299        // SAFETY: `phydev` is pointing to a valid object by the type invariant of `Self`.
300        // So it's just an FFI call.
301        to_result(unsafe { bindings::genphy_read_abilities(phydev) })
302    }
303}
304
305/// Defines certain other features this PHY supports (like interrupts).
306///
307/// These flag values are used in [`Driver::FLAGS`].
308pub mod flags {
309    /// PHY is internal.
310    pub const IS_INTERNAL: u32 = bindings::PHY_IS_INTERNAL;
311    /// PHY needs to be reset after the refclk is enabled.
312    pub const RST_AFTER_CLK_EN: u32 = bindings::PHY_RST_AFTER_CLK_EN;
313    /// Polling is used to detect PHY status changes.
314    pub const POLL_CABLE_TEST: u32 = bindings::PHY_POLL_CABLE_TEST;
315    /// Don't suspend.
316    pub const ALWAYS_CALL_SUSPEND: u32 = bindings::PHY_ALWAYS_CALL_SUSPEND;
317}
318
319/// An adapter for the registration of a PHY driver.
320struct Adapter<T: Driver> {
321    _p: PhantomData<T>,
322}
323
324impl<T: Driver> Adapter<T> {
325    /// # Safety
326    ///
327    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
328    unsafe extern "C" fn soft_reset_callback(
329        phydev: *mut bindings::phy_device,
330    ) -> core::ffi::c_int {
331        from_result(|| {
332            // SAFETY: This callback is called only in contexts
333            // where we hold `phy_device->lock`, so the accessors on
334            // `Device` are okay to call.
335            let dev = unsafe { Device::from_raw(phydev) };
336            T::soft_reset(dev)?;
337            Ok(0)
338        })
339    }
340
341    /// # Safety
342    ///
343    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
344    unsafe extern "C" fn get_features_callback(
345        phydev: *mut bindings::phy_device,
346    ) -> core::ffi::c_int {
347        from_result(|| {
348            // SAFETY: This callback is called only in contexts
349            // where we hold `phy_device->lock`, so the accessors on
350            // `Device` are okay to call.
351            let dev = unsafe { Device::from_raw(phydev) };
352            T::get_features(dev)?;
353            Ok(0)
354        })
355    }
356
357    /// # Safety
358    ///
359    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
360    unsafe extern "C" fn suspend_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int {
361        from_result(|| {
362            // SAFETY: The C core code ensures that the accessors on
363            // `Device` are okay to call even though `phy_device->lock`
364            // might not be held.
365            let dev = unsafe { Device::from_raw(phydev) };
366            T::suspend(dev)?;
367            Ok(0)
368        })
369    }
370
371    /// # Safety
372    ///
373    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
374    unsafe extern "C" fn resume_callback(phydev: *mut bindings::phy_device) -> core::ffi::c_int {
375        from_result(|| {
376            // SAFETY: The C core code ensures that the accessors on
377            // `Device` are okay to call even though `phy_device->lock`
378            // might not be held.
379            let dev = unsafe { Device::from_raw(phydev) };
380            T::resume(dev)?;
381            Ok(0)
382        })
383    }
384
385    /// # Safety
386    ///
387    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
388    unsafe extern "C" fn config_aneg_callback(
389        phydev: *mut bindings::phy_device,
390    ) -> core::ffi::c_int {
391        from_result(|| {
392            // SAFETY: This callback is called only in contexts
393            // where we hold `phy_device->lock`, so the accessors on
394            // `Device` are okay to call.
395            let dev = unsafe { Device::from_raw(phydev) };
396            T::config_aneg(dev)?;
397            Ok(0)
398        })
399    }
400
401    /// # Safety
402    ///
403    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
404    unsafe extern "C" fn read_status_callback(
405        phydev: *mut bindings::phy_device,
406    ) -> core::ffi::c_int {
407        from_result(|| {
408            // SAFETY: This callback is called only in contexts
409            // where we hold `phy_device->lock`, so the accessors on
410            // `Device` are okay to call.
411            let dev = unsafe { Device::from_raw(phydev) };
412            T::read_status(dev)?;
413            Ok(0)
414        })
415    }
416
417    /// # Safety
418    ///
419    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
420    unsafe extern "C" fn match_phy_device_callback(
421        phydev: *mut bindings::phy_device,
422    ) -> core::ffi::c_int {
423        // SAFETY: This callback is called only in contexts
424        // where we hold `phy_device->lock`, so the accessors on
425        // `Device` are okay to call.
426        let dev = unsafe { Device::from_raw(phydev) };
427        T::match_phy_device(dev) as i32
428    }
429
430    /// # Safety
431    ///
432    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
433    unsafe extern "C" fn read_mmd_callback(
434        phydev: *mut bindings::phy_device,
435        devnum: i32,
436        regnum: u16,
437    ) -> i32 {
438        from_result(|| {
439            // SAFETY: This callback is called only in contexts
440            // where we hold `phy_device->lock`, so the accessors on
441            // `Device` are okay to call.
442            let dev = unsafe { Device::from_raw(phydev) };
443            // CAST: the C side verifies devnum < 32.
444            let ret = T::read_mmd(dev, devnum as u8, regnum)?;
445            Ok(ret.into())
446        })
447    }
448
449    /// # Safety
450    ///
451    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
452    unsafe extern "C" fn write_mmd_callback(
453        phydev: *mut bindings::phy_device,
454        devnum: i32,
455        regnum: u16,
456        val: u16,
457    ) -> i32 {
458        from_result(|| {
459            // SAFETY: This callback is called only in contexts
460            // where we hold `phy_device->lock`, so the accessors on
461            // `Device` are okay to call.
462            let dev = unsafe { Device::from_raw(phydev) };
463            T::write_mmd(dev, devnum as u8, regnum, val)?;
464            Ok(0)
465        })
466    }
467
468    /// # Safety
469    ///
470    /// `phydev` must be passed by the corresponding callback in `phy_driver`.
471    unsafe extern "C" fn link_change_notify_callback(phydev: *mut bindings::phy_device) {
472        // SAFETY: This callback is called only in contexts
473        // where we hold `phy_device->lock`, so the accessors on
474        // `Device` are okay to call.
475        let dev = unsafe { Device::from_raw(phydev) };
476        T::link_change_notify(dev);
477    }
478}
479
480/// Driver structure for a particular PHY type.
481///
482/// Wraps the kernel's [`struct phy_driver`].
483/// This is used to register a driver for a particular PHY type with the kernel.
484///
485/// # Invariants
486///
487/// `self.0` is always in a valid state.
488///
489/// [`struct phy_driver`]: srctree/include/linux/phy.h
490#[repr(transparent)]
491pub struct DriverVTable(Opaque<bindings::phy_driver>);
492
493// SAFETY: `DriverVTable` doesn't expose any &self method to access internal data, so it's safe to
494// share `&DriverVTable` across execution context boundries.
495unsafe impl Sync for DriverVTable {}
496
497/// Creates a [`DriverVTable`] instance from [`Driver`].
498///
499/// This is used by [`module_phy_driver`] macro to create a static array of `phy_driver`.
500///
501/// [`module_phy_driver`]: crate::module_phy_driver
502pub const fn create_phy_driver<T: Driver>() -> DriverVTable {
503    // INVARIANT: All the fields of `struct phy_driver` are initialized properly.
504    DriverVTable(Opaque::new(bindings::phy_driver {
505        name: T::NAME.as_char_ptr().cast_mut(),
506        flags: T::FLAGS,
507        phy_id: T::PHY_DEVICE_ID.id,
508        phy_id_mask: T::PHY_DEVICE_ID.mask_as_int(),
509        soft_reset: if T::HAS_SOFT_RESET {
510            Some(Adapter::<T>::soft_reset_callback)
511        } else {
512            None
513        },
514        get_features: if T::HAS_GET_FEATURES {
515            Some(Adapter::<T>::get_features_callback)
516        } else {
517            None
518        },
519        match_phy_device: if T::HAS_MATCH_PHY_DEVICE {
520            Some(Adapter::<T>::match_phy_device_callback)
521        } else {
522            None
523        },
524        suspend: if T::HAS_SUSPEND {
525            Some(Adapter::<T>::suspend_callback)
526        } else {
527            None
528        },
529        resume: if T::HAS_RESUME {
530            Some(Adapter::<T>::resume_callback)
531        } else {
532            None
533        },
534        config_aneg: if T::HAS_CONFIG_ANEG {
535            Some(Adapter::<T>::config_aneg_callback)
536        } else {
537            None
538        },
539        read_status: if T::HAS_READ_STATUS {
540            Some(Adapter::<T>::read_status_callback)
541        } else {
542            None
543        },
544        read_mmd: if T::HAS_READ_MMD {
545            Some(Adapter::<T>::read_mmd_callback)
546        } else {
547            None
548        },
549        write_mmd: if T::HAS_WRITE_MMD {
550            Some(Adapter::<T>::write_mmd_callback)
551        } else {
552            None
553        },
554        link_change_notify: if T::HAS_LINK_CHANGE_NOTIFY {
555            Some(Adapter::<T>::link_change_notify_callback)
556        } else {
557            None
558        },
559        // SAFETY: The rest is zeroed out to initialize `struct phy_driver`,
560        // sets `Option<&F>` to be `None`.
561        ..unsafe { core::mem::MaybeUninit::<bindings::phy_driver>::zeroed().assume_init() }
562    }))
563}
564
565/// Driver implementation for a particular PHY type.
566///
567/// This trait is used to create a [`DriverVTable`].
568#[vtable]
569pub trait Driver {
570    /// Defines certain other features this PHY supports.
571    /// It is a combination of the flags in the [`flags`] module.
572    const FLAGS: u32 = 0;
573
574    /// The friendly name of this PHY type.
575    const NAME: &'static CStr;
576
577    /// This driver only works for PHYs with IDs which match this field.
578    /// The default id and mask are zero.
579    const PHY_DEVICE_ID: DeviceId = DeviceId::new_with_custom_mask(0, 0);
580
581    /// Issues a PHY software reset.
582    fn soft_reset(_dev: &mut Device) -> Result {
583        kernel::build_error(VTABLE_DEFAULT_ERROR)
584    }
585
586    /// Probes the hardware to determine what abilities it has.
587    fn get_features(_dev: &mut Device) -> Result {
588        kernel::build_error(VTABLE_DEFAULT_ERROR)
589    }
590
591    /// Returns true if this is a suitable driver for the given phydev.
592    /// If not implemented, matching is based on [`Driver::PHY_DEVICE_ID`].
593    fn match_phy_device(_dev: &Device) -> bool {
594        false
595    }
596
597    /// Configures the advertisement and resets auto-negotiation
598    /// if auto-negotiation is enabled.
599    fn config_aneg(_dev: &mut Device) -> Result {
600        kernel::build_error(VTABLE_DEFAULT_ERROR)
601    }
602
603    /// Determines the negotiated speed and duplex.
604    fn read_status(_dev: &mut Device) -> Result<u16> {
605        kernel::build_error(VTABLE_DEFAULT_ERROR)
606    }
607
608    /// Suspends the hardware, saving state if needed.
609    fn suspend(_dev: &mut Device) -> Result {
610        kernel::build_error(VTABLE_DEFAULT_ERROR)
611    }
612
613    /// Resumes the hardware, restoring state if needed.
614    fn resume(_dev: &mut Device) -> Result {
615        kernel::build_error(VTABLE_DEFAULT_ERROR)
616    }
617
618    /// Overrides the default MMD read function for reading a MMD register.
619    fn read_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16) -> Result<u16> {
620        kernel::build_error(VTABLE_DEFAULT_ERROR)
621    }
622
623    /// Overrides the default MMD write function for writing a MMD register.
624    fn write_mmd(_dev: &mut Device, _devnum: u8, _regnum: u16, _val: u16) -> Result {
625        kernel::build_error(VTABLE_DEFAULT_ERROR)
626    }
627
628    /// Callback for notification of link change.
629    fn link_change_notify(_dev: &mut Device) {}
630}
631
632/// Registration structure for PHY drivers.
633///
634/// Registers [`DriverVTable`] instances with the kernel. They will be unregistered when dropped.
635///
636/// # Invariants
637///
638/// The `drivers` slice are currently registered to the kernel via `phy_drivers_register`.
639pub struct Registration {
640    drivers: Pin<&'static mut [DriverVTable]>,
641}
642
643// SAFETY: The only action allowed in a `Registration` instance is dropping it, which is safe to do
644// from any thread because `phy_drivers_unregister` can be called from any thread context.
645unsafe impl Send for Registration {}
646
647impl Registration {
648    /// Registers a PHY driver.
649    pub fn register(
650        module: &'static crate::ThisModule,
651        drivers: Pin<&'static mut [DriverVTable]>,
652    ) -> Result<Self> {
653        if drivers.is_empty() {
654            return Err(code::EINVAL);
655        }
656        // SAFETY: The type invariants of [`DriverVTable`] ensure that all elements of
657        // the `drivers` slice are initialized properly. `drivers` will not be moved.
658        // So it's just an FFI call.
659        to_result(unsafe {
660            bindings::phy_drivers_register(drivers[0].0.get(), drivers.len().try_into()?, module.0)
661        })?;
662        // INVARIANT: The `drivers` slice is successfully registered to the kernel via `phy_drivers_register`.
663        Ok(Registration { drivers })
664    }
665}
666
667impl Drop for Registration {
668    fn drop(&mut self) {
669        // SAFETY: The type invariants guarantee that `self.drivers` is valid.
670        // So it's just an FFI call.
671        unsafe {
672            bindings::phy_drivers_unregister(self.drivers[0].0.get(), self.drivers.len() as i32)
673        };
674    }
675}
676
677/// An identifier for PHY devices on an MDIO/MII bus.
678///
679/// Represents the kernel's `struct mdio_device_id`. This is used to find an appropriate
680/// PHY driver.
681pub struct DeviceId {
682    id: u32,
683    mask: DeviceMask,
684}
685
686impl DeviceId {
687    /// Creates a new instance with the exact match mask.
688    pub const fn new_with_exact_mask(id: u32) -> Self {
689        DeviceId {
690            id,
691            mask: DeviceMask::Exact,
692        }
693    }
694
695    /// Creates a new instance with the model match mask.
696    pub const fn new_with_model_mask(id: u32) -> Self {
697        DeviceId {
698            id,
699            mask: DeviceMask::Model,
700        }
701    }
702
703    /// Creates a new instance with the vendor match mask.
704    pub const fn new_with_vendor_mask(id: u32) -> Self {
705        DeviceId {
706            id,
707            mask: DeviceMask::Vendor,
708        }
709    }
710
711    /// Creates a new instance with a custom match mask.
712    pub const fn new_with_custom_mask(id: u32, mask: u32) -> Self {
713        DeviceId {
714            id,
715            mask: DeviceMask::Custom(mask),
716        }
717    }
718
719    /// Creates a new instance from [`Driver`].
720    pub const fn new_with_driver<T: Driver>() -> Self {
721        T::PHY_DEVICE_ID
722    }
723
724    /// Get a `mask` as u32.
725    pub const fn mask_as_int(&self) -> u32 {
726        self.mask.as_int()
727    }
728
729    // macro use only
730    #[doc(hidden)]
731    pub const fn mdio_device_id(&self) -> bindings::mdio_device_id {
732        bindings::mdio_device_id {
733            phy_id: self.id,
734            phy_id_mask: self.mask.as_int(),
735        }
736    }
737}
738
739enum DeviceMask {
740    Exact,
741    Model,
742    Vendor,
743    Custom(u32),
744}
745
746impl DeviceMask {
747    const MASK_EXACT: u32 = !0;
748    const MASK_MODEL: u32 = !0 << 4;
749    const MASK_VENDOR: u32 = !0 << 10;
750
751    const fn as_int(&self) -> u32 {
752        match self {
753            DeviceMask::Exact => Self::MASK_EXACT,
754            DeviceMask::Model => Self::MASK_MODEL,
755            DeviceMask::Vendor => Self::MASK_VENDOR,
756            DeviceMask::Custom(mask) => *mask,
757        }
758    }
759}
760
761/// Declares a kernel module for PHYs drivers.
762///
763/// This creates a static array of kernel's `struct phy_driver` and registers it.
764/// This also corresponds to the kernel's `MODULE_DEVICE_TABLE` macro, which embeds the information
765/// for module loading into the module binary file. Every driver needs an entry in `device_table`.
766///
767/// # Examples
768///
769/// ```
770/// # mod module_phy_driver_sample {
771/// use kernel::c_str;
772/// use kernel::net::phy::{self, DeviceId};
773/// use kernel::prelude::*;
774///
775/// kernel::module_phy_driver! {
776///     drivers: [PhySample],
777///     device_table: [
778///         DeviceId::new_with_driver::<PhySample>()
779///     ],
780///     name: "rust_sample_phy",
781///     author: "Rust for Linux Contributors",
782///     description: "Rust sample PHYs driver",
783///     license: "GPL",
784/// }
785///
786/// struct PhySample;
787///
788/// #[vtable]
789/// impl phy::Driver for PhySample {
790///     const NAME: &'static CStr = c_str!("PhySample");
791///     const PHY_DEVICE_ID: phy::DeviceId = phy::DeviceId::new_with_exact_mask(0x00000001);
792/// }
793/// # }
794/// ```
795///
796/// This expands to the following code:
797///
798/// ```ignore
799/// use kernel::c_str;
800/// use kernel::net::phy::{self, DeviceId};
801/// use kernel::prelude::*;
802///
803/// struct Module {
804///     _reg: ::kernel::net::phy::Registration,
805/// }
806///
807/// module! {
808///     type: Module,
809///     name: "rust_sample_phy",
810///     author: "Rust for Linux Contributors",
811///     description: "Rust sample PHYs driver",
812///     license: "GPL",
813/// }
814///
815/// struct PhySample;
816///
817/// #[vtable]
818/// impl phy::Driver for PhySample {
819///     const NAME: &'static CStr = c_str!("PhySample");
820///     const PHY_DEVICE_ID: phy::DeviceId = phy::DeviceId::new_with_exact_mask(0x00000001);
821/// }
822///
823/// const _: () = {
824///     static mut DRIVERS: [::kernel::net::phy::DriverVTable; 1] =
825///         [::kernel::net::phy::create_phy_driver::<PhySample>()];
826///
827///     impl ::kernel::Module for Module {
828///         fn init(module: &'static ThisModule) -> Result<Self> {
829///             let drivers = unsafe { &mut DRIVERS };
830///             let mut reg = ::kernel::net::phy::Registration::register(
831///                 module,
832///                 ::core::pin::Pin::static_mut(drivers),
833///             )?;
834///             Ok(Module { _reg: reg })
835///         }
836///     }
837/// };
838///
839/// #[cfg(MODULE)]
840/// #[no_mangle]
841/// static __mod_mdio__phydev_device_table: [::kernel::bindings::mdio_device_id; 2] = [
842///     ::kernel::bindings::mdio_device_id {
843///         phy_id: 0x00000001,
844///         phy_id_mask: 0xffffffff,
845///     },
846///     ::kernel::bindings::mdio_device_id {
847///         phy_id: 0,
848///         phy_id_mask: 0,
849///     },
850/// ];
851/// ```
852#[macro_export]
853macro_rules! module_phy_driver {
854    (@replace_expr $_t:tt $sub:expr) => {$sub};
855
856    (@count_devices $($x:expr),*) => {
857        0usize $(+ $crate::module_phy_driver!(@replace_expr $x 1usize))*
858    };
859
860    (@device_table [$($dev:expr),+]) => {
861        // SAFETY: C will not read off the end of this constant since the last element is zero.
862        #[cfg(MODULE)]
863        #[no_mangle]
864        static __mod_mdio__phydev_device_table: [$crate::bindings::mdio_device_id;
865            $crate::module_phy_driver!(@count_devices $($dev),+) + 1] = [
866            $($dev.mdio_device_id()),+,
867            $crate::bindings::mdio_device_id {
868                phy_id: 0,
869                phy_id_mask: 0
870            }
871        ];
872    };
873
874    (drivers: [$($driver:ident),+ $(,)?], device_table: [$($dev:expr),+ $(,)?], $($f:tt)*) => {
875        struct Module {
876            _reg: $crate::net::phy::Registration,
877        }
878
879        $crate::prelude::module! {
880            type: Module,
881            $($f)*
882        }
883
884        const _: () = {
885            static mut DRIVERS: [$crate::net::phy::DriverVTable;
886                $crate::module_phy_driver!(@count_devices $($driver),+)] =
887                [$($crate::net::phy::create_phy_driver::<$driver>()),+];
888
889            impl $crate::Module for Module {
890                fn init(module: &'static ThisModule) -> Result<Self> {
891                    // SAFETY: The anonymous constant guarantees that nobody else can access
892                    // the `DRIVERS` static. The array is used only in the C side.
893                    let drivers = unsafe { &mut DRIVERS };
894                    let mut reg = $crate::net::phy::Registration::register(
895                        module,
896                        ::core::pin::Pin::static_mut(drivers),
897                    )?;
898                    Ok(Module { _reg: reg })
899                }
900            }
901        };
902
903        $crate::module_phy_driver!(@device_table [$($dev),+]);
904    }
905}