feat(esp32c3): add a working USB-Serial driver

justfile

@@ -94,12 +94,12 @@ build-c3 board:
         --bin {{ board }}
 
 # flash an ESP32-C3 with the MnemOS WiFi Buddy firmware
-flash-c3 board: (_get-cargo-command "espflash" "cargo-espflash") (build-c3 board)
+flash-c3 board *espflash-args: (_get-cargo-command "espflash" "cargo-espflash") (build-c3 board)
     cd {{ _espbuddy_dir }} && \
         {{ _cargo }} espflash flash \
             --release \
             --bin {{ board }} \
-            --monitor
+            {{ espflash-args }}
 
 # run crowtty (a host serial multiplexer, log viewer, and pseudo-keyboard)
 crowtty *FLAGS:

platforms/esp32c3-buddy/Cargo.toml

@@ -65,6 +65,11 @@ version = "0.1.37"
 features = ["attributes"]
 default-features = false
 
+[dependencies.futures]
+version = "0.3.21"
+default-features = false
+features = ["async-await"]
+
 ### patches ###
 
 [patch.crates-io.maitake]

platforms/esp32c3-buddy/src/bin/qtpy.rs

@@ -5,11 +5,9 @@ extern crate alloc;
 
 use esp32c3_hal::{
     clock::ClockControl, peripherals::Peripherals, prelude::*, systimer::SystemTimer,
-    timer::TimerGroup, Rtc, IO,
+    timer::TimerGroup, Rtc,
 };
 use esp_backtrace as _;
-use esp_println::println;
-use mnemos_esp32c3_buddy::drivers;
 
 #[entry]
 fn main() -> ! {
@@ -39,50 +37,17 @@ fn main() -> ! {
     rtc.rwdt.disable();
     wdt0.disable();
     wdt1.disable();
-    println!("Hello world!");
 
     let k = mnemos_esp32c3_buddy::init();
-
-    let io = IO::new(peripherals.GPIO, peripherals.IO_MUX);
-
-    // initialize SimpleSerial driver
-    k.initialize({
-        use esp32c3_hal::uart::{
-            config::{Config, DataBits, Parity, StopBits},
-            TxRxPins, Uart,
-        };
-
-        let config = Config {
-            baudrate: 115200,
-            data_bits: DataBits::DataBits8,
-            parity: Parity::ParityNone,
-            stop_bits: StopBits::STOP1,
-        };
-
-        let pins = TxRxPins::new_tx_rx(
-            io.pins.gpio1.into_push_pull_output(),
-            io.pins.gpio2.into_floating_input(),
-        );
-
-        let uart0 = Uart::new_with_config(
-            peripherals.UART0,
-            Some(config),
-            Some(pins),
-            &clocks,
-            &mut system.peripheral_clock_control,
-        );
-
-        drivers::uart::C3Uart::uart0(uart0).register(k, 4096, 4096)
-    })
-    .unwrap();
-
+    mnemos_esp32c3_buddy::spawn_serial(
+        &k,
+        peripherals.USB_DEVICE,
+        &mut system.peripheral_clock_control,
+    );
     mnemos_esp32c3_buddy::spawn_daemons(k);
 
     // configure system timer
     let syst = SystemTimer::new(peripherals.SYSTIMER);
-
-    println!("SYSTIMER Current value = {}", SystemTimer::now());
-
     // Alarm 1 will be used to generate "sleep until" interrupts.
     let alarm1 = syst.alarm1;
 

platforms/esp32c3-buddy/src/bin/xiao.rs

@@ -5,11 +5,9 @@ extern crate alloc;
 
 use esp32c3_hal::{
     clock::ClockControl, peripherals::Peripherals, prelude::*, systimer::SystemTimer,
-    timer::TimerGroup, Rtc, IO,
+    timer::TimerGroup, Rtc,
 };
 use esp_backtrace as _;
-use esp_println::println;
-use mnemos_esp32c3_buddy::drivers;
 
 #[entry]
 fn main() -> ! {
@@ -39,50 +37,17 @@ fn main() -> ! {
     rtc.rwdt.disable();
     wdt0.disable();
     wdt1.disable();
-    println!("Hello world!");
-
     let k = mnemos_esp32c3_buddy::init();
 
-    let io = IO::new(peripherals.GPIO, peripherals.IO_MUX);
-
-    // initialize SimpleSerial driver
-    k.initialize({
-        use esp32c3_hal::uart::{
-            config::{Config, DataBits, Parity, StopBits},
-            TxRxPins, Uart,
-        };
-
-        let config = Config {
-            baudrate: 115200,
-            data_bits: DataBits::DataBits8,
-            parity: Parity::ParityNone,
-            stop_bits: StopBits::STOP1,
-        };
-
-        let pins = TxRxPins::new_tx_rx(
-            io.pins.gpio1.into_push_pull_output(),
-            io.pins.gpio2.into_floating_input(),
-        );
-
-        let uart0 = Uart::new_with_config(
-            peripherals.UART0,
-            Some(config),
-            Some(pins),
-            &clocks,
-            &mut system.peripheral_clock_control,
-        );
-
-        drivers::uart::C3Uart::uart0(uart0).register(k, 4096, 4096)
-    })
-    .unwrap();
-
     mnemos_esp32c3_buddy::spawn_daemons(k);
+    mnemos_esp32c3_buddy::spawn_serial(
+        &k,
+        peripherals.USB_DEVICE,
+        &mut system.peripheral_clock_control,
+    );
 
     // configure system timer
     let syst = SystemTimer::new(peripherals.SYSTIMER);
-
-    println!("SYSTIMER Current value = {}", SystemTimer::now());
-
     // Alarm 1 will be used to generate "sleep until" interrupts.
     let alarm1 = syst.alarm1;
 

platforms/esp32c3-buddy/src/drivers/mod.rs

@@ -1 +1,2 @@
 pub mod uart;
+pub mod usb_serial;

platforms/esp32c3-buddy/src/drivers/uart.rs

@@ -1,9 +1,13 @@
 use core::{
-    ptr::{null_mut},
+    ptr::null_mut,
     sync::atomic::{AtomicPtr, Ordering},
 };
 
-use esp32c3_hal::{uart::{Uart, Instance}, prelude::interrupt, peripherals::UART0};
+use esp32c3_hal::{
+    peripherals::UART0,
+    prelude::interrupt,
+    uart::{Instance, Uart},
+};
 
 use kernel::{
     comms::{
@@ -47,7 +51,10 @@ pub struct C3Uart<T: 'static> {
 
 impl C3Uart<UART0> {
     pub fn uart0(uart: Uart<'static, UART0>) -> Self {
-        Self { uart, tx_done: &UART0_TX_DONE }
+        Self {
+            uart,
+            tx_done: &UART0_TX_DONE,
+        }
     }
 
     pub fn handle_uart0_int() {
@@ -89,7 +96,9 @@ impl<T: Instance> C3Uart<T> {
 
             self.uart.listen_tx_done();
             // TODO(eliza): what should we do if this errors?
-            self.uart.write_bytes(&rx).expect("UART write bytes should succeed?");
+            self.uart
+                .write_bytes(&rx)
+                .expect("UART write bytes should succeed?");
 
             // wait for the write to complete
             wait.await.expect("UART TX_DONE WaitCell is never closed!");
@@ -104,7 +113,6 @@ impl<T: Instance> C3Uart<T> {
         cap_in: usize,
         cap_out: usize,
     ) -> Result<(), registry::RegistrationError> {
-
         let (kprod, kcons) = KChannel::<Message<SimpleSerialService>>::new_async(4)
             .await
             .split();
@@ -137,4 +145,4 @@ fn UART0() {
     } else {
         panic!("unexpected UART interrupt!");
     }
-}
+}