feat: embassy-usb-logger and example for rpi pico

* Add embassy-usb-logger which allows logging over USB for any device
  implementing embassy-usb
* Add example using logger for rpi pico.

2 files changed, 32 insertions, 0 deletions

diff --git a/examples/rp/Cargo.toml b/examples/rp/Cargo.toml
index 31f688305..250228862 100644
--- a/examples/rp/Cargo.toml
+++ b/examples/rp/Cargo.toml
@@ -13,6 +13,7 @@ embassy-rp = { version = "0.1.0", path = "../../embassy-rp", features = ["defmt"
 embassy-usb = { version = "0.1.0", path = "../../embassy-usb", features = ["defmt"] }
 embassy-net = { version = "0.1.0", path = "../../embassy-net", features = ["defmt", "nightly", "tcp", "dhcpv4", "medium-ethernet", "pool-16"] }
 embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
+embassy-usb-logger = { version = "0.1.0", path = "../../embassy-usb-logger" }
 
 defmt = "0.3"
 defmt-rtt = "0.3"
@@ -32,6 +33,7 @@ embedded-hal-async = { version = "0.1.0-alpha.3" }
 embedded-io = { version = "0.3.1", features = ["async", "defmt"] }
 embedded-storage = { version = "0.3" }
 static_cell = "1.0.0"
+log = "0.4"
 
 [profile.release]
 debug = true
diff --git a/examples/rp/src/bin/usb_logger.rs b/examples/rp/src/bin/usb_logger.rs
new file mode 100644
index 000000000..52417a02e
--- /dev/null
+++ b/examples/rp/src/bin/usb_logger.rs
@@ -0,0 +1,30 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use embassy_executor::Spawner;
+use embassy_rp::interrupt;
+use embassy_rp::peripherals::USB;
+use embassy_rp::usb::Driver;
+use embassy_time::{Duration, Timer};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::task]
+async fn logger_task(driver: Driver<'static, USB>) {
+    embassy_usb_logger::run!(1024, log::LevelFilter::Info, driver);
+}
+
+#[embassy_executor::main]
+async fn main(spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    let irq = interrupt::take!(USBCTRL_IRQ);
+    let driver = Driver::new(p.USB, irq);
+    spawner.spawn(logger_task(driver)).unwrap();
+
+    let mut counter = 0;
+    loop {
+        counter += 1;
+        log::info!("Tick {}", counter);
+        Timer::after(Duration::from_secs(1)).await;
+    }
+}