Add embassy-lora crate

This crate contains async radio drivers for various lora drivers that
work with embassy timers. The code is imported from Drogue Device (
https://github.com/drogue-iot/drogue-device)

The radio drivers integrate with the async LoRaWAN MAC layer in the
lorawan-device crate.

Also added is an example for the STM32WL55 and for STM32L0 (requires
the LoRa Discovery board) for LoRaWAN. Future work is to make the
underlying radio drivers using fully async SPI when communicating
with the peripheral.

examples/stm32l0/Cargo.toml

@@ -23,6 +23,10 @@ embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["
 embassy-hal-common = {version = "0.1.0", path = "../../embassy-hal-common" }
 embassy-macros = { path = "../../embassy-macros" }
 
+embassy-lora = { version = "0.1.0", path = "../../embassy-lora", features = ["sx127x", "time"] }
+lorawan-device = { git = "https://github.com/lulf/rust-lorawan.git", rev = "a373d06fa8858d251bc70d5789cebcd9a638ec42", default-features = false, features = ["async"] }
+lorawan-encoding = { git = "https://github.com/lulf/rust-lorawan.git", rev = "a373d06fa8858d251bc70d5789cebcd9a638ec42", default-features = false, features = ["default-crypto"] }
+
 defmt = "0.2.3"
 defmt-rtt = "0.2.0"
 

examples/stm32l0/src/bin/lorawan.rs

@@ -0,0 +1,104 @@
+//! This example runs on the STM32 LoRa Discovery board which has a builtin Semtech Sx127x radio
+#![no_std]
+#![no_main]
+#![macro_use]
+#![allow(dead_code)]
+#![feature(generic_associated_types)]
+#![feature(type_alias_impl_trait)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+
+use embassy_lora::{sx127x::*, LoraTimer};
+use embassy_stm32::{
+    dbgmcu::Dbgmcu,
+    dma::NoDma,
+    exti::ExtiInput,
+    gpio::{Input, Level, Output, Pull, Speed},
+    rcc,
+    rng::Rng,
+    spi,
+    time::U32Ext,
+    Peripherals,
+};
+use lorawan_device::async_device::{region, Device, JoinMode};
+use lorawan_encoding::default_crypto::DefaultFactory as Crypto;
+
+fn config() -> embassy_stm32::Config {
+    let mut config = embassy_stm32::Config::default();
+    config.rcc = config.rcc.clock_src(embassy_stm32::rcc::ClockSrc::HSI16);
+    config
+}
+
+#[embassy::main(config = "config()")]
+async fn main(_spawner: embassy::executor::Spawner, mut p: Peripherals) {
+    unsafe {
+        Dbgmcu::enable_all();
+    }
+
+    let mut rcc = rcc::Rcc::new(p.RCC);
+    let _ = rcc.enable_hsi48(&mut p.SYSCFG, p.CRS);
+
+    // SPI for sx127x
+    let spi = spi::Spi::new(
+        p.SPI1,
+        p.PB3,
+        p.PA7,
+        p.PA6,
+        NoDma,
+        NoDma,
+        200_000.hz(),
+        spi::Config::default(),
+    );
+
+    let cs = Output::new(p.PA15, Level::High, Speed::Low);
+    let reset = Output::new(p.PC0, Level::High, Speed::Low);
+    let _ = Input::new(p.PB1, Pull::None);
+
+    let ready = Input::new(p.PB4, Pull::Up);
+    let ready_pin = ExtiInput::new(ready, p.EXTI4);
+
+    let radio = Sx127xRadio::new(
+        spi,
+        cs,
+        reset,
+        ready_pin,
+        DummySwitch,
+        &mut embassy::time::Delay,
+    )
+    .unwrap();
+
+    let region = region::EU868::default().into();
+    let mut radio_buffer = [0; 256];
+    let mut device: Device<'_, _, Crypto, _, _> = Device::new(
+        region,
+        radio,
+        LoraTimer,
+        Rng::new(p.RNG),
+        &mut radio_buffer[..],
+    );
+
+    defmt::info!("Joining LoRaWAN network");
+
+    // TODO: Adjust the EUI and Keys according to your network credentials
+    device
+        .join(&JoinMode::OTAA {
+            deveui: [0, 0, 0, 0, 0, 0, 0, 0],
+            appeui: [0, 0, 0, 0, 0, 0, 0, 0],
+            appkey: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        })
+        .await
+        .ok()
+        .unwrap();
+    defmt::info!("LoRaWAN network joined");
+
+    defmt::info!("Sending 'PING'");
+    device.send(b"PING", 1, false).await.ok().unwrap();
+    defmt::info!("Message sent!");
+}
+
+pub struct DummySwitch;
+impl RadioSwitch for DummySwitch {
+    fn set_rx(&mut self) {}
+    fn set_tx(&mut self) {}
+}

examples/stm32wl55/Cargo.toml

@@ -19,8 +19,12 @@ defmt-error = []
 [dependencies]
 embassy = { version = "0.1.0", path = "../../embassy", features = ["defmt", "defmt-trace"] }
 embassy-traits = { version = "0.1.0", path = "../../embassy-traits", features = ["defmt"] }
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["defmt", "defmt-trace", "stm32wl55jc_cm4", "time-driver-tim2", "memory-x", "subghz"]  }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["defmt", "defmt-trace", "stm32wl55jc_cm4", "time-driver-tim2", "memory-x", "subghz", "unstable-pac"]  }
 embassy-hal-common = {version = "0.1.0", path = "../../embassy-hal-common" }
+embassy-lora = { version = "0.1.0", path = "../../embassy-lora", features = ["stm32wl", "time"] }
+
+lorawan-device = { git = "https://github.com/lulf/rust-lorawan.git", rev = "a373d06fa8858d251bc70d5789cebcd9a638ec42", default-features = false, features = ["async"] }
+lorawan-encoding = { git = "https://github.com/lulf/rust-lorawan.git", rev = "a373d06fa8858d251bc70d5789cebcd9a638ec42", default-features = false, features = ["default-crypto"] }
 
 defmt = "0.2.3"
 defmt-rtt = "0.2.0"

examples/stm32wl55/src/bin/lorawan.rs

@@ -0,0 +1,79 @@
+#![no_std]
+#![no_main]
+#![macro_use]
+#![allow(dead_code)]
+#![feature(generic_associated_types)]
+#![feature(type_alias_impl_trait)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+
+use embassy_lora::{stm32wl::*, LoraTimer};
+use embassy_stm32::{
+    dbgmcu::Dbgmcu,
+    dma::NoDma,
+    gpio::{Level, Output, Pin, Speed},
+    interrupt, pac, rcc,
+    rng::Rng,
+    subghz::*,
+    Peripherals,
+};
+use lorawan_device::async_device::{region, Device, JoinMode};
+use lorawan_encoding::default_crypto::DefaultFactory as Crypto;
+
+fn config() -> embassy_stm32::Config {
+    let mut config = embassy_stm32::Config::default();
+    config.rcc = config.rcc.clock_src(embassy_stm32::rcc::ClockSrc::HSI16);
+    config
+}
+
+#[embassy::main(config = "config()")]
+async fn main(_spawner: embassy::executor::Spawner, p: Peripherals) {
+    unsafe {
+        Dbgmcu::enable_all();
+        let mut rcc = rcc::Rcc::new(p.RCC);
+        rcc.enable_lsi();
+        pac::RCC.ccipr().modify(|w| {
+            w.set_rngsel(0b01);
+        });
+    }
+
+    let ctrl1 = Output::new(p.PC3.degrade(), Level::High, Speed::High);
+    let ctrl2 = Output::new(p.PC4.degrade(), Level::High, Speed::High);
+    let ctrl3 = Output::new(p.PC5.degrade(), Level::High, Speed::High);
+    let rfs = RadioSwitch::new(ctrl1, ctrl2, ctrl3);
+
+    let radio = SubGhz::new(p.SUBGHZSPI, p.PA5, p.PA7, p.PA6, NoDma, NoDma);
+
+    let irq = interrupt::take!(SUBGHZ_RADIO);
+    static mut RADIO_STATE: SubGhzState<'static> = SubGhzState::new();
+    let radio = unsafe { SubGhzRadio::new(&mut RADIO_STATE, radio, rfs, irq) };
+
+    let region = region::EU868::default().into();
+    let mut radio_buffer = [0; 256];
+    let mut device: Device<'_, _, Crypto, _, _> = Device::new(
+        region,
+        radio,
+        LoraTimer,
+        Rng::new(p.RNG),
+        &mut radio_buffer[..],
+    );
+
+    defmt::info!("Joining LoRaWAN network");
+
+    // TODO: Adjust the EUI and Keys according to your network credentials
+    device
+        .join(&JoinMode::OTAA {
+            deveui: [0, 0, 0, 0, 0, 0, 0, 0],
+            appeui: [0, 0, 0, 0, 0, 0, 0, 0],
+            appkey: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
+        })
+        .await
+        .ok()
+        .unwrap();
+    defmt::info!("LoRaWAN network joined");
+
+    defmt::info!("Sending 'PING'");
+    device.send(b"PING", 1, false).await.ok().unwrap();
+    defmt::info!("Message sent!");
+}