usb: add -usb-serial crate, fix warnings and stable build.

examples/nrf/src/bin/usb_serial.rs

@@ -0,0 +1,91 @@
+#![no_std]
+#![no_main]
+#![feature(generic_associated_types)]
+#![feature(type_alias_impl_trait)]
+
+use core::mem;
+use defmt::*;
+use embassy::executor::Spawner;
+use embassy::time::{Duration, Timer};
+use embassy_nrf::interrupt;
+use embassy_nrf::pac;
+use embassy_nrf::usb::Driver;
+use embassy_nrf::Peripherals;
+use embassy_usb::driver::{EndpointIn, EndpointOut};
+use embassy_usb::{Config, UsbDeviceBuilder};
+use embassy_usb_serial::{CdcAcmClass, State};
+use futures::future::join3;
+
+use defmt_rtt as _; // global logger
+use panic_probe as _;
+
+#[embassy::main]
+async fn main(_spawner: Spawner, p: Peripherals) {
+    let clock: pac::CLOCK = unsafe { mem::transmute(()) };
+    let power: pac::POWER = unsafe { mem::transmute(()) };
+
+    info!("Enabling ext hfosc...");
+    clock.tasks_hfclkstart.write(|w| unsafe { w.bits(1) });
+    while clock.events_hfclkstarted.read().bits() != 1 {}
+
+    info!("Waiting for vbus...");
+    while !power.usbregstatus.read().vbusdetect().is_vbus_present() {}
+    info!("vbus OK");
+
+    // Create the driver, from the HAL.
+    let irq = interrupt::take!(USBD);
+    let driver = Driver::new(p.USBD, irq);
+
+    // Create embassy-usb Config
+    let config = Config::new(0xc0de, 0xcafe);
+
+    // Create embassy-usb DeviceBuilder using the driver and config.
+    // It needs some buffers for building the descriptors.
+    let mut device_descriptor = [0; 256];
+    let mut config_descriptor = [0; 256];
+    let mut bos_descriptor = [0; 256];
+    let mut control_buf = [0; 7];
+
+    let mut state = State::new();
+
+    let mut builder = UsbDeviceBuilder::new(
+        driver,
+        config,
+        &mut device_descriptor,
+        &mut config_descriptor,
+        &mut bos_descriptor,
+        &mut control_buf,
+    );
+
+    // Create classes on the builder.
+    let mut class = CdcAcmClass::new(&mut builder, &mut state, 64);
+
+    // Build the builder.
+    let mut usb = builder.build();
+
+    // Run the USB device.
+    let fut1 = usb.run();
+
+    // Do stuff with the classes
+    let fut2 = async {
+        let mut buf = [0; 64];
+        loop {
+            let n = class.read_ep.read(&mut buf).await.unwrap();
+            let data = &buf[..n];
+            info!("data: {:x}", data);
+        }
+    };
+    let fut3 = async {
+        loop {
+            info!("writing...");
+            class.write_ep.write(b"Hello World!\r\n").await.unwrap();
+            info!("written");
+
+            Timer::after(Duration::from_secs(1)).await;
+        }
+    };
+
+    // Run everything concurrently.
+    // If we had made everything `'static` above instead, we could do this using separate tasks instead.
+    join3(fut1, fut2, fut3).await;
+}