Mutex for SPI
//! Blocking shared SPI bus
use core::cell::RefCell;
-use core::fmt::Debug;
+use embassy::blocking_mutex::raw::RawMutex;
+use embassy::blocking_mutex::Mutex;
use embedded_hal_1::digital::blocking::OutputPin;
use embedded_hal_1::spi;
use embedded_hal_1::spi::blocking::{SpiBusFlush, SpiDevice};
-#[derive(Copy, Clone, Eq, PartialEq, Debug)]
-pub enum SpiBusDeviceError<BUS, CS> {
- Spi(BUS),
- Cs(CS),
-}
-
-impl<BUS, CS> spi::Error for SpiBusDeviceError<BUS, CS>
-where
- BUS: spi::Error + Debug,
- CS: Debug,
-{
- fn kind(&self) -> spi::ErrorKind {
- match self {
- Self::Spi(e) => e.kind(),
- Self::Cs(_) => spi::ErrorKind::Other,
- }
- }
-}
+use crate::shared_bus::spi::SpiBusDeviceError;
-pub struct SpiBusDevice<'a, BUS, CS> {
- bus: &'a RefCell<BUS>,
+pub struct SpiBusDevice<'a, M: RawMutex, BUS, CS> {
+ bus: &'a Mutex<M, RefCell<BUS>>,
cs: CS,
}
-impl<'a, BUS, CS> SpiBusDevice<'a, BUS, CS> {
- pub fn new(bus: &'a RefCell<BUS>, cs: CS) -> Self {
+impl<'a, M: RawMutex, BUS, CS> SpiBusDevice<'a, M, BUS, CS> {
+ pub fn new(bus: &'a Mutex<M, RefCell<BUS>>, cs: CS) -> Self {
Self { bus, cs }
}
}
-impl<'a, BUS, CS> spi::ErrorType for SpiBusDevice<'a, BUS, CS>
+impl<'a, M: RawMutex, BUS, CS> spi::ErrorType for SpiBusDevice<'a, M, BUS, CS>
where
BUS: spi::ErrorType,
CS: OutputPin,
@@ -44,20 +28,25 @@ where
type Error = SpiBusDeviceError<BUS::Error, CS::Error>;
}
-impl<BUS, CS> SpiDevice for SpiBusDevice<'_, BUS, CS>
+impl<BUS, M, CS> SpiDevice for SpiBusDevice<'_, M, BUS, CS>
where
+ M: RawMutex,
BUS: SpiBusFlush,
CS: OutputPin,
{
type Bus = BUS;
+
fn transaction<R>(&mut self, f: impl FnOnce(&mut Self::Bus) -> Result<R, BUS::Error>) -> Result<R, Self::Error> {
- let mut bus = self.bus.borrow_mut();
self.cs.set_low().map_err(SpiBusDeviceError::Cs)?;
+ let (f_res, flush_res) = self.bus.lock(|bus| {
+ let mut bus = bus.borrow_mut();
let f_res = f(&mut bus);
-
// On failure, it's important to still flush and deassert CS.
let flush_res = bus.flush();
+ (f_res, flush_res)
+ });
+
let cs_res = self.cs.set_high();
let f_res = f_res.map_err(SpiBusDeviceError::Spi)?;
