Merge branch 'master' into stm-dualcore

4 files changed, 345 insertions, 1 deletions

diff --git a/examples/rp/src/bin/assign_resources.rs b/examples/rp/src/bin/assign_resources.rs
new file mode 100644
index 000000000..ff6eff4a2
--- /dev/null
+++ b/examples/rp/src/bin/assign_resources.rs
@@ -0,0 +1,79 @@
+//! This example demonstrates how to assign resources to multiple tasks by splitting up the peripherals.
+//! It is not about sharing the same resources between tasks, see sharing.rs for that or head to https://embassy.dev/book/#_sharing_peripherals_between_tasks)
+//! Of course splitting up resources and sharing resources can be combined, yet this example is only about splitting up resources.
+//!
+//! There are basically two ways we demonstrate here:
+//! 1) Assigning resources to a task by passing parts of the peripherals
+//! 2) Assigning resources to a task by passing a struct with the split up peripherals, using the assign-resources macro
+//!
+//! using four LEDs on Pins 10, 11, 20 and 21
+
+#![no_std]
+#![no_main]
+
+use assign_resources::assign_resources;
+use defmt::*;
+use embassy_executor::Spawner;
+use embassy_rp::gpio::{Level, Output};
+use embassy_rp::peripherals::{self, PIN_20, PIN_21};
+use embassy_time::Timer;
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    // initialize the peripherals
+    let p = embassy_rp::init(Default::default());
+
+    // 1) Assigning a resource to a task by passing parts of the peripherals.
+    spawner
+        .spawn(double_blinky_manually_assigned(spawner, p.PIN_20, p.PIN_21))
+        .unwrap();
+
+    // 2) Using the assign-resources macro to assign resources to a task.
+    // we perform the split, see further below for the definition of the resources struct
+    let r = split_resources!(p);
+    // and then we can use them
+    spawner.spawn(double_blinky_macro_assigned(spawner, r.leds)).unwrap();
+}
+
+// 1) Assigning a resource to a task by passing parts of the peripherals.
+#[embassy_executor::task]
+async fn double_blinky_manually_assigned(_spawner: Spawner, pin_20: PIN_20, pin_21: PIN_21) {
+    let mut led_20 = Output::new(pin_20, Level::Low);
+    let mut led_21 = Output::new(pin_21, Level::High);
+
+    loop {
+        info!("toggling leds");
+        led_20.toggle();
+        led_21.toggle();
+        Timer::after_secs(1).await;
+    }
+}
+
+// 2) Using the assign-resources macro to assign resources to a task.
+// first we define the resources we want to assign to the task using the assign_resources! macro
+// basically this will split up the peripherals struct into smaller structs, that we define here
+// naming is up to you, make sure your future self understands what you did here
+assign_resources! {
+    leds: Leds{
+        led_10: PIN_10,
+        led_11: PIN_11,
+    }
+    // add more resources to more structs if needed, for example defining one struct for each task
+}
+// this could be done in another file and imported here, but for the sake of simplicity we do it here
+// see https://github.com/adamgreig/assign-resources for more information
+
+// 2) Using the split resources in a task
+#[embassy_executor::task]
+async fn double_blinky_macro_assigned(_spawner: Spawner, r: Leds) {
+    let mut led_10 = Output::new(r.led_10, Level::Low);
+    let mut led_11 = Output::new(r.led_11, Level::High);
+
+    loop {
+        info!("toggling leds");
+        led_10.toggle();
+        led_11.toggle();
+        Timer::after_secs(1).await;
+    }
+}
diff --git a/examples/rp/src/bin/shared_bus.rs b/examples/rp/src/bin/shared_bus.rs
new file mode 100644
index 000000000..c6cb5d64c
--- /dev/null
+++ b/examples/rp/src/bin/shared_bus.rs
@@ -0,0 +1,115 @@
+//! This example shows how to share (async) I2C and SPI buses between multiple devices.
+
+#![no_std]
+#![no_main]
+
+use defmt::*;
+use embassy_embedded_hal::shared_bus::asynch::i2c::I2cDevice;
+use embassy_embedded_hal::shared_bus::asynch::spi::SpiDevice;
+use embassy_executor::Spawner;
+use embassy_rp::bind_interrupts;
+use embassy_rp::gpio::{AnyPin, Level, Output};
+use embassy_rp::i2c::{self, I2c, InterruptHandler};
+use embassy_rp::peripherals::{I2C1, SPI1};
+use embassy_rp::spi::{self, Spi};
+use embassy_sync::blocking_mutex::raw::NoopRawMutex;
+use embassy_sync::mutex::Mutex;
+use embassy_time::Timer;
+use static_cell::StaticCell;
+use {defmt_rtt as _, panic_probe as _};
+
+type Spi1Bus = Mutex<NoopRawMutex, Spi<'static, SPI1, spi::Async>>;
+type I2c1Bus = Mutex<NoopRawMutex, I2c<'static, I2C1, i2c::Async>>;
+
+bind_interrupts!(struct Irqs {
+    I2C1_IRQ => InterruptHandler<I2C1>;
+});
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    info!("Here we go!");
+
+    // Shared I2C bus
+    let i2c = I2c::new_async(p.I2C1, p.PIN_15, p.PIN_14, Irqs, i2c::Config::default());
+    static I2C_BUS: StaticCell<I2c1Bus> = StaticCell::new();
+    let i2c_bus = I2C_BUS.init(Mutex::new(i2c));
+
+    spawner.must_spawn(i2c_task_a(i2c_bus));
+    spawner.must_spawn(i2c_task_b(i2c_bus));
+
+    // Shared SPI bus
+    let spi_cfg = spi::Config::default();
+    let spi = Spi::new(p.SPI1, p.PIN_10, p.PIN_11, p.PIN_12, p.DMA_CH0, p.DMA_CH1, spi_cfg);
+    static SPI_BUS: StaticCell<Spi1Bus> = StaticCell::new();
+    let spi_bus = SPI_BUS.init(Mutex::new(spi));
+
+    // Chip select pins for the SPI devices
+    let cs_a = Output::new(AnyPin::from(p.PIN_0), Level::High);
+    let cs_b = Output::new(AnyPin::from(p.PIN_1), Level::High);
+
+    spawner.must_spawn(spi_task_a(spi_bus, cs_a));
+    spawner.must_spawn(spi_task_b(spi_bus, cs_b));
+}
+
+#[embassy_executor::task]
+async fn i2c_task_a(i2c_bus: &'static I2c1Bus) {
+    let i2c_dev = I2cDevice::new(i2c_bus);
+    let _sensor = DummyI2cDeviceDriver::new(i2c_dev, 0xC0);
+    loop {
+        info!("i2c task A");
+        Timer::after_secs(1).await;
+    }
+}
+
+#[embassy_executor::task]
+async fn i2c_task_b(i2c_bus: &'static I2c1Bus) {
+    let i2c_dev = I2cDevice::new(i2c_bus);
+    let _sensor = DummyI2cDeviceDriver::new(i2c_dev, 0xDE);
+    loop {
+        info!("i2c task B");
+        Timer::after_secs(1).await;
+    }
+}
+
+#[embassy_executor::task]
+async fn spi_task_a(spi_bus: &'static Spi1Bus, cs: Output<'static>) {
+    let spi_dev = SpiDevice::new(spi_bus, cs);
+    let _sensor = DummySpiDeviceDriver::new(spi_dev);
+    loop {
+        info!("spi task A");
+        Timer::after_secs(1).await;
+    }
+}
+
+#[embassy_executor::task]
+async fn spi_task_b(spi_bus: &'static Spi1Bus, cs: Output<'static>) {
+    let spi_dev = SpiDevice::new(spi_bus, cs);
+    let _sensor = DummySpiDeviceDriver::new(spi_dev);
+    loop {
+        info!("spi task B");
+        Timer::after_secs(1).await;
+    }
+}
+
+// Dummy I2C device driver, using `embedded-hal-async`
+struct DummyI2cDeviceDriver<I2C: embedded_hal_async::i2c::I2c> {
+    _i2c: I2C,
+}
+
+impl<I2C: embedded_hal_async::i2c::I2c> DummyI2cDeviceDriver<I2C> {
+    fn new(i2c_dev: I2C, _address: u8) -> Self {
+        Self { _i2c: i2c_dev }
+    }
+}
+
+// Dummy SPI device driver, using `embedded-hal-async`
+struct DummySpiDeviceDriver<SPI: embedded_hal_async::spi::SpiDevice> {
+    _spi: SPI,
+}
+
+impl<SPI: embedded_hal_async::spi::SpiDevice> DummySpiDeviceDriver<SPI> {
+    fn new(spi_dev: SPI) -> Self {
+        Self { _spi: spi_dev }
+    }
+}
diff --git a/examples/rp/src/bin/sharing.rs b/examples/rp/src/bin/sharing.rs
new file mode 100644
index 000000000..5416e20ce
--- /dev/null
+++ b/examples/rp/src/bin/sharing.rs
@@ -0,0 +1,150 @@
+//! This example shows some common strategies for sharing resources between tasks.
+//!
+//! We demonstrate five different ways of sharing, covering different use cases:
+//! - Atomics: This method is used for simple values, such as bool and u8..u32
+//! - Blocking Mutex: This is used for sharing non-async things, using Cell/RefCell for interior mutability.
+//! - Async Mutex: This is used for sharing async resources, where you need to hold the lock across await points.
+//!   The async Mutex has interior mutability built-in, so no RefCell is needed.
+//! - Cell: For sharing Copy types between tasks running on the same executor.
+//! - RefCell: When you want &mut access to a value shared between tasks running on the same executor.
+//!
+//! More information: https://embassy.dev/book/#_sharing_peripherals_between_tasks
+
+#![no_std]
+#![no_main]
+
+use core::cell::{Cell, RefCell};
+use core::sync::atomic::{AtomicU32, Ordering};
+
+use cortex_m_rt::entry;
+use defmt::info;
+use embassy_executor::{Executor, InterruptExecutor};
+use embassy_rp::clocks::RoscRng;
+use embassy_rp::interrupt::{InterruptExt, Priority};
+use embassy_rp::peripherals::UART0;
+use embassy_rp::uart::{self, InterruptHandler, UartTx};
+use embassy_rp::{bind_interrupts, interrupt};
+use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
+use embassy_sync::{blocking_mutex, mutex};
+use embassy_time::{Duration, Ticker};
+use rand::RngCore;
+use static_cell::{ConstStaticCell, StaticCell};
+use {defmt_rtt as _, panic_probe as _};
+
+type UartAsyncMutex = mutex::Mutex<CriticalSectionRawMutex, UartTx<'static, UART0, uart::Async>>;
+
+struct MyType {
+    inner: u32,
+}
+
+static EXECUTOR_HI: InterruptExecutor = InterruptExecutor::new();
+static EXECUTOR_LOW: StaticCell<Executor> = StaticCell::new();
+
+// Use Atomics for simple values
+static ATOMIC: AtomicU32 = AtomicU32::new(0);
+
+// Use blocking Mutex with Cell/RefCell for sharing non-async things
+static MUTEX_BLOCKING: blocking_mutex::Mutex<CriticalSectionRawMutex, RefCell<MyType>> =
+    blocking_mutex::Mutex::new(RefCell::new(MyType { inner: 0 }));
+
+bind_interrupts!(struct Irqs {
+    UART0_IRQ => InterruptHandler<UART0>;
+});
+
+#[interrupt]
+unsafe fn SWI_IRQ_0() {
+    EXECUTOR_HI.on_interrupt()
+}
+
+#[entry]
+fn main() -> ! {
+    let p = embassy_rp::init(Default::default());
+    info!("Here we go!");
+
+    let uart = UartTx::new(p.UART0, p.PIN_0, p.DMA_CH0, uart::Config::default());
+    // Use the async Mutex for sharing async things (built-in interior mutability)
+    static UART: StaticCell<UartAsyncMutex> = StaticCell::new();
+    let uart = UART.init(mutex::Mutex::new(uart));
+
+    // High-priority executor: runs in interrupt mode
+    interrupt::SWI_IRQ_0.set_priority(Priority::P3);
+    let spawner = EXECUTOR_HI.start(interrupt::SWI_IRQ_0);
+    spawner.must_spawn(task_a(uart));
+
+    // Low priority executor: runs in thread mode
+    let executor = EXECUTOR_LOW.init(Executor::new());
+    executor.run(|spawner| {
+        // No Mutex needed when sharing between tasks running on the same executor
+
+        // Use Cell for Copy-types
+        static CELL: ConstStaticCell<Cell<[u8; 4]>> = ConstStaticCell::new(Cell::new([0; 4]));
+        let cell = CELL.take();
+
+        // Use RefCell for &mut access
+        static REF_CELL: ConstStaticCell<RefCell<MyType>> = ConstStaticCell::new(RefCell::new(MyType { inner: 0 }));
+        let ref_cell = REF_CELL.take();
+
+        spawner.must_spawn(task_b(uart, cell, ref_cell));
+        spawner.must_spawn(task_c(cell, ref_cell));
+    });
+}
+
+#[embassy_executor::task]
+async fn task_a(uart: &'static UartAsyncMutex) {
+    let mut ticker = Ticker::every(Duration::from_secs(1));
+    loop {
+        let random = RoscRng.next_u32();
+
+        {
+            let mut uart = uart.lock().await;
+            uart.write(b"task a").await.unwrap();
+            // The uart lock is released when it goes out of scope
+        }
+
+        ATOMIC.store(random, Ordering::Relaxed);
+
+        MUTEX_BLOCKING.lock(|x| x.borrow_mut().inner = random);
+
+        ticker.next().await;
+    }
+}
+
+#[embassy_executor::task]
+async fn task_b(uart: &'static UartAsyncMutex, cell: &'static Cell<[u8; 4]>, ref_cell: &'static RefCell<MyType>) {
+    let mut ticker = Ticker::every(Duration::from_secs(1));
+    loop {
+        let random = RoscRng.next_u32();
+
+        uart.lock().await.write(b"task b").await.unwrap();
+
+        cell.set(random.to_be_bytes());
+
+        ref_cell.borrow_mut().inner = random;
+
+        ticker.next().await;
+    }
+}
+
+#[embassy_executor::task]
+async fn task_c(cell: &'static Cell<[u8; 4]>, ref_cell: &'static RefCell<MyType>) {
+    let mut ticker = Ticker::every(Duration::from_secs(1));
+    loop {
+        info!("=======================");
+
+        let atomic_val = ATOMIC.load(Ordering::Relaxed);
+        info!("atomic: {}", atomic_val);
+
+        MUTEX_BLOCKING.lock(|x| {
+            let val = x.borrow().inner;
+            info!("blocking mutex: {}", val);
+        });
+
+        let cell_val = cell.get();
+        info!("cell: {:?}", cell_val);
+
+        let ref_cell_val = ref_cell.borrow().inner;
+        info!("ref_cell: {:?}", ref_cell_val);
+
+        ticker.next().await;
+    }
+}
diff --git a/examples/rp/src/bin/uart_buffered_split.rs b/examples/rp/src/bin/uart_buffered_split.rs
index fac61aa04..468d2b61a 100644
--- a/examples/rp/src/bin/uart_buffered_split.rs
+++ b/examples/rp/src/bin/uart_buffered_split.rs
@@ -31,7 +31,7 @@ async fn main(spawner: Spawner) {
     static RX_BUF: StaticCell<[u8; 16]> = StaticCell::new();
     let rx_buf = &mut RX_BUF.init([0; 16])[..];
     let uart = BufferedUart::new(uart, Irqs, tx_pin, rx_pin, tx_buf, rx_buf, Config::default());
-    let (rx, mut tx) = uart.split();
+    let (mut tx, rx) = uart.split();
 
     unwrap!(spawner.spawn(reader(rx)));