embassy/embassy-stm32/src/can/bxcan.rs
2021-08-18 21:58:50 +02:00

141 lines
3.5 KiB
Rust

use core::marker::PhantomData;
use core::ops::{Deref, DerefMut};
use embassy::util::Unborrow;
use embassy_hal_common::unborrow;
use crate::gpio::Pin;
use crate::{peripherals, rcc::RccPeripheral};
pub use bxcan::*;
pub struct Can<'d, T: Instance + bxcan::Instance> {
phantom: PhantomData<&'d mut T>,
can: bxcan::Can<T>,
}
impl<'d, T: Instance + bxcan::Instance> Can<'d, T> {
pub fn new(
peri: impl Unborrow<Target = T> + 'd,
// irq: impl Unborrow<Target = T::Interrupt> + 'd,
rx: impl Unborrow<Target = impl RxPin<T>> + 'd,
tx: impl Unborrow<Target = impl TxPin<T>> + 'd,
) -> Self {
unborrow!(peri, rx, tx);
unsafe {
rx.set_as_af(rx.af_num());
tx.set_as_af(tx.af_num());
}
T::enable();
T::reset();
// TODO: CAN2 also required CAN1 clock
Self {
phantom: PhantomData,
can: bxcan::Can::new(peri),
}
}
}
impl<'d, T: Instance + bxcan::Instance> Drop for Can<'d, T> {
fn drop(&mut self) {
// Cannot call `free()` because it moves the instance.
// Manually reset the peripheral.
unsafe {
T::regs().mcr().write(|w| w.set_reset(true));
}
T::disable();
}
}
impl<'d, T: Instance + bxcan::Instance> Deref for Can<'d, T> {
type Target = bxcan::Can<T>;
fn deref(&self) -> &Self::Target {
&self.can
}
}
impl<'d, T: Instance + bxcan::Instance> DerefMut for Can<'d, T> {
fn deref_mut(&mut self) -> &mut Self::Target {
&mut self.can
}
}
pub(crate) mod sealed {
use super::*;
pub trait Instance {
fn regs() -> &'static crate::pac::can::Can;
}
pub trait RxPin<T: Instance>: Pin {
fn af_num(&self) -> u8;
}
pub trait TxPin<T: Instance>: Pin {
fn af_num(&self) -> u8;
}
}
pub trait Instance: sealed::Instance + RccPeripheral {}
pub trait RxPin<T: Instance>: sealed::RxPin<T> {}
pub trait TxPin<T: Instance>: sealed::TxPin<T> {}
crate::pac::peripherals!(
(can, $inst:ident) => {
impl sealed::Instance for peripherals::$inst {
fn regs() -> &'static crate::pac::can::Can {
&crate::pac::$inst
}
}
impl Instance for peripherals::$inst {}
unsafe impl bxcan::Instance for peripherals::$inst {
const REGISTERS: *mut bxcan::RegisterBlock = crate::pac::$inst.0 as *mut _;
}
};
);
crate::pac::peripherals!(
// TODO: rename CAN to CAN1 on yaml level??
(can, CAN) => {
unsafe impl bxcan::FilterOwner for peripherals::CAN {
const NUM_FILTER_BANKS: u8 = 14;
}
};
(can, CAN1) => {
unsafe impl bxcan::FilterOwner for peripherals::CAN1 {
const NUM_FILTER_BANKS: u8 = 14;
}
};
(can, CAN2) => {
// TODO: when CAN2 existis, we have 28 filter banks
unsafe impl bxcan::MasterInstance for peripherals::CAN1 {}
};
);
macro_rules! impl_pin {
($inst:ident, $pin:ident, $signal:ident, $af:expr) => {
impl $signal<peripherals::$inst> for peripherals::$pin {}
impl sealed::$signal<peripherals::$inst> for peripherals::$pin {
fn af_num(&self) -> u8 {
$af
}
}
};
}
crate::pac::peripheral_pins!(
($inst:ident, can, CAN, $pin:ident, TX, $af:expr) => {
impl_pin!($inst, $pin, TxPin, $af);
};
($inst:ident, can, CAN, $pin:ident, RX, $af:expr) => {
impl_pin!($inst, $pin, RxPin, $af);
};
);