CAN support with bxcan crate

embassy-stm32/src/bxcan.rs

@@ -0,0 +1,128 @@
+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> 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 {}
+
+    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!(
+    (bxcan, $inst:ident) => {
+        impl sealed::Instance for peripherals::$inst {}
+
+        impl Instance for peripherals::$inst {}
+
+        unsafe impl bxcan::Instance for peripherals::$inst {
+            const REGISTERS: *mut bxcan::RegisterBlock = crate::pac::$inst.0 as *mut _;
+        }
+    };
+    // (bxcan, CAN) => {
+    //     unsafe impl bxcan::FilterOwner for Can<peripherals::CAN> {
+    //         const NUM_FILTER_BANKS: u8 = 14;
+    //     }
+    // };
+);
+
+crate::pac::peripherals!(
+    // TODO: rename CAN to CAN1 on yaml level??
+    (bxcan, CAN) => {
+        unsafe impl bxcan::FilterOwner for peripherals::CAN {
+            const NUM_FILTER_BANKS: u8 = 14;
+        }
+    };
+    (bxcan, CAN1) => {
+        unsafe impl bxcan::FilterOwner for peripherals::CAN1 {
+            const NUM_FILTER_BANKS: u8 = 14;
+        }
+    };
+    (bxcan, CAN2) => {
+        // TODO: when CAN2 existis, we have 28 filter banks
+        unsafe impl bxcan::MasterInstance for peripherals::CAN1 {}
+    };
+);
+
+macro_rules! impl_pin {
+    ($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, bxcan, CAN, $pin:ident, TX, $af:expr) => {
+        impl_pin!($inst, $pin, TxPin, $af);
+    };
+    ($inst:ident, bxcan, CAN, $pin:ident, RX, $af:expr) => {
+        impl_pin!($inst, $pin, RxPin, $af);
+    };
+);

embassy-stm32/src/lib.rs

@@ -27,6 +27,8 @@ mod time_driver;
 
 #[cfg(adc)]
 pub mod adc;
+#[cfg(bxcan)]
+pub mod bxcan;
 #[cfg(dac)]
 pub mod dac;
 #[cfg(dbgmcu)]