stm32: consolidate modules

embassy-stm32/src/can.rs

@@ -0,0 +1,120 @@
+//! Async low power Serial.
+//!
+//! The peripheral is autmatically enabled and disabled as required to save power.
+//! Lowest power consumption can only be guaranteed if the send receive futures
+//! are dropped correctly (e.g. not using `mem::forget()`).
+
+use bxcan;
+use bxcan::Interrupts;
+use core::future::Future;
+use embassy::interrupt::Interrupt;
+use embassy::util::InterruptFuture;
+use nb;
+use nb::block;
+
+use crate::interrupt;
+
+/// Interface to the Serial peripheral
+pub struct Can<T: Instance> {
+    can: bxcan::Can<T>,
+    tx_int: T::TInterrupt,
+    rx_int: T::RInterrupt,
+}
+
+impl<T: Instance> Can<T> {
+    pub fn new(mut can: bxcan::Can<T>, tx_int: T::TInterrupt, rx_int: T::RInterrupt) -> Self {
+        // Sync to the bus and start normal operation.
+        can.enable_interrupts(
+            Interrupts::TRANSMIT_MAILBOX_EMPTY | Interrupts::FIFO0_MESSAGE_PENDING,
+        );
+        block!(can.enable()).unwrap();
+
+        Can {
+            can: can,
+            tx_int: tx_int,
+            rx_int: rx_int,
+        }
+    }
+
+    /// Sends can frame.
+    ///
+    /// This method async-blocks until the frame is transmitted.
+    pub fn transmit<'a>(&'a mut self, frame: &'a bxcan::Frame) -> impl Future<Output = ()> + 'a {
+        async move {
+            let fut = InterruptFuture::new(&mut self.tx_int);
+            // Infallible
+            self.can.transmit(frame).unwrap();
+
+            fut.await;
+        }
+    }
+
+    /// Receive can frame.
+    ///
+    /// This method async-blocks until the frame is received.
+    pub fn receive<'a>(&'a mut self) -> impl Future<Output = bxcan::Frame> + 'a {
+        async move {
+            let mut frame: Option<bxcan::Frame>;
+
+            loop {
+                let fut = InterruptFuture::new(&mut self.rx_int);
+                frame = match self.can.receive() {
+                    Ok(frame) => Some(frame),
+                    Err(nb::Error::WouldBlock) => None,
+                    Err(nb::Error::Other(_)) => None, // Ignore overrun errors.
+                };
+                if frame.is_some() {
+                    break;
+                }
+                fut.await;
+            }
+
+            frame.unwrap()
+        }
+    }
+}
+
+mod private {
+    pub trait Sealed {}
+}
+
+pub trait Instance: bxcan::Instance + private::Sealed {
+    type TInterrupt: Interrupt;
+    type RInterrupt: Interrupt;
+}
+
+macro_rules! can {
+    ($($can:ident => ($tint:ident, $rint:ident),)+) => {
+        $(
+            impl private::Sealed for crate::hal::can::Can<crate::pac::$can> {}
+            impl Instance for crate::hal::can::Can<crate::pac::$can> {
+                type TInterrupt = interrupt::$tint;
+                type RInterrupt = interrupt::$rint;
+            }
+        )+
+    }
+}
+
+#[cfg(any(
+    feature = "stm32f401",
+    feature = "stm32f405",
+    feature = "stm32f407",
+    feature = "stm32f410",
+    feature = "stm32f411",
+    feature = "stm32f412",
+    feature = "stm32f413",
+    feature = "stm32f415",
+    feature = "stm32f417",
+    feature = "stm32f423",
+    feature = "stm32f427",
+    feature = "stm32f429",
+    feature = "stm32f437",
+    feature = "stm32f439",
+    feature = "stm32f446",
+    feature = "stm32f469",
+    feature = "stm32f479",
+))]
+can! {
+    CAN1 => (CAN1_TX, CAN1_RX0),
+    CAN2 => (CAN2_TX, CAN2_RX0),
+}