embassy/embassy-stm32/src/can/bxcan.rs
2022-02-24 00:37:15 +01:00

115 lines
2.9 KiB
Rust

use core::marker::PhantomData;
use core::ops::{Deref, DerefMut};
use embassy::util::Unborrow;
use embassy_hal_common::unborrow;
use crate::gpio::sealed::AFType;
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,
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(), AFType::Input);
tx.set_as_af(tx.af_num(), AFType::OutputPushPull);
}
T::enable();
T::reset();
Self {
phantom: PhantomData,
can: bxcan::Can::builder(peri).enable(),
}
}
}
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 {
pub trait Instance {
fn regs() -> &'static crate::pac::can::Can;
}
}
pub trait Instance: sealed::Instance + RccPeripheral {}
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!(
(can, CAN) => {
unsafe impl bxcan::FilterOwner for peripherals::CAN {
const NUM_FILTER_BANKS: u8 = 14;
}
};
// Only correct when CAN2 also exists… Fix on yaml level?
// There are only 14 filter banks when CAN2 is not available.
(can, CAN1) => {
unsafe impl bxcan::FilterOwner for peripherals::CAN1 {
const NUM_FILTER_BANKS: u8 = 28;
}
};
(can, CAN2) => {
// CAN2 is always a slave instance where CAN1 is the master instance
unsafe impl bxcan::MasterInstance for peripherals::CAN1 {}
};
(can, CAN3) => {
unsafe impl bxcan::FilterOwner for peripherals::CAN3 {
const NUM_FILTER_BANKS: u8 = 14;
}
};
);
pin_trait!(RxPin, Instance);
pin_trait!(TxPin, Instance);