refactor: unify SimpleLed via embedded-hal, remove Option<L> from BoardParts

- Added embedded-hal 1.0 as direct dep (already transitive via embedded-hal-async)
- SimpleLed<P: OutputPin> now generic over any HAL — single definition in driver/
- Removed duplicate SimpleLed from board/esp32s3.rs and board/wio_tracker_l1.rs
- Changed BoardParts.led from Option<L> to L — boards with no LED use ()
- Display task calls led.set_rgb() unconditionally (no-op for () boards)
- RAK board: led: () instead of led: None

firmware/Cargo.lock

@@ -390,6 +390,7 @@ dependencies = [
  "embassy-usb",
  "embassy-usb-driver",
  "embedded-graphics",
+ "embedded-hal 1.0.0",
  "embedded-hal-async",
  "embedded-io-async 0.7.0",
  "esp-backtrace",

firmware/Cargo.toml

@@ -21,6 +21,7 @@ categories = ["embedded", "hardware-support", "no-std"]
 cfg-if = "1.0"
 critical-section = "1.2"
 defmt = "1.0"
+embedded-hal = "1.0"
 embedded-hal-async = "1.0"
 embassy-embedded-hal = "0.6"
 embassy-executor = "0.9"

firmware/src/board/esp32s3.rs

@@ -18,20 +18,6 @@ use crate::hal::esp32s3 as mcu;
 
 pub use mcu::{I2cBus as DisplayI2c, SpiBus};
 
-// ── LED driver ──────────────────────────────────────────────────────
-
-pub struct SimpleLed(pub Output<'static>);
-
-impl super::traits::RgbLed for SimpleLed {
-    async fn set_rgb(&mut self, r: u8, g: u8, b: u8) {
-        if r > 0 || g > 0 || b > 0 {
-            self.0.set_high();
-        } else {
-            self.0.set_low();
-        }
-    }
-}
-
 // ── Concrete peripheral types ───────────────────────────────────────
 
 type Nss = Output<'static>;

firmware/src/board/heltec_v3.rs

@@ -11,7 +11,7 @@ use static_cell::StaticCell;
 
 use super::esp32s3;
 use super::traits::{BoardParts, LoRaBoard};
-use super::esp32s3::SimpleLed;
+use crate::driver::simple_led::SimpleLed;
 use crate::hal::esp32s3 as mcu;
 
 pub use super::esp32s3::{
@@ -19,7 +19,7 @@ pub use super::esp32s3::{
 };
 
 pub type UsbDriver = esp_hal::otg_fs::asynch::Driver<'static>;
-pub type LedDriver = SimpleLed;
+pub type LedDriver = SimpleLed<Output<'static>>;
 
 pub struct UsbParts {
     pub driver: UsbDriver,
@@ -84,7 +84,7 @@ impl LoRaBoard for Board {
 
         // White LED on GPIO35
         let led_pin = Output::new(p.GPIO35, Level::Low, OutputConfig::default());
-        let led = Some(SimpleLed(led_pin));
+        let led = SimpleLed(led_pin);
 
         BoardParts {
             radio,

firmware/src/board/heltec_v3_uart.rs

@@ -10,7 +10,7 @@ use esp_hal::gpio::{Level, Output, OutputConfig};
 
 use super::esp32s3;
 use super::traits::{BoardParts, LoRaBoard};
-use super::esp32s3::SimpleLed;
+use crate::driver::simple_led::SimpleLed;
 use crate::hal::esp32s3 as mcu;
 
 pub use super::esp32s3::{
@@ -18,7 +18,7 @@ pub use super::esp32s3::{
 };
 
 pub type UartDriver = esp_hal::uart::Uart<'static, esp_hal::Async>;
-pub type LedDriver = SimpleLed;
+pub type LedDriver = SimpleLed<Output<'static>>;
 
 pub struct UartParts {
     pub driver: UartDriver,
@@ -80,7 +80,7 @@ impl LoRaBoard for Board {
 
         // White LED on GPIO35
         let led_pin = Output::new(p.GPIO35, Level::Low, OutputConfig::default());
-        let led = Some(SimpleLed(led_pin));
+        let led = SimpleLed(led_pin);
 
         BoardParts {
             radio,

firmware/src/board/heltec_v4.rs

@@ -3,7 +3,7 @@ use static_cell::StaticCell;
 
 use super::esp32s3;
 use super::traits::{BoardParts, LoRaBoard};
-use super::esp32s3::SimpleLed;
+use crate::driver::simple_led::SimpleLed;
 use crate::hal::esp32s3 as mcu;
 
 pub use super::esp32s3::{
@@ -12,7 +12,7 @@ pub use super::esp32s3::{
 
 pub type UsbDriver = esp_hal::otg_fs::asynch::Driver<'static>;
 
-pub type LedDriver = SimpleLed;
+pub type LedDriver = SimpleLed<Output<'static>>;
 
 pub struct UsbParts {
     pub driver: UsbDriver,
@@ -77,7 +77,7 @@ impl LoRaBoard for Board {
 
         // Orange LED on GPIO35
         let led_pin = Output::new(p.GPIO35, Level::Low, OutputConfig::default());
-        let led = Some(SimpleLed(led_pin));
+        let led = SimpleLed(led_pin);
 
         BoardParts {
             radio,

firmware/src/board/rak_wisblock_4631.rs

@@ -137,7 +137,7 @@ impl LoRaBoard for Board {
             radio,
             host,
             display,
-            led: None,
+            led: (),
             mac: Self::mac_address(),
         }
     }

firmware/src/board/traits.rs

@@ -56,6 +56,6 @@ pub struct BoardParts<R, C, D, L> {
     pub radio: R,
     pub host: C,
     pub display: Option<D>,
-    pub led: Option<L>,
+    pub led: L,
     pub mac: [u8; 6],
 }

firmware/src/board/wio_tracker_l1.rs

@@ -21,21 +21,7 @@ pub type RadioDriver = Sx126x<RadioSpiDevice, Iv, Sx1262>;
 pub type UsbDriver = mcu::UsbNrfDriver;
 pub type DisplayI2c = mcu::I2cBus;
 
-// ── LED driver (green LED on P1.01) ─────────────────────────────────
+pub type LedDriver = crate::driver::simple_led::SimpleLed<Output<'static>>;
-
-pub struct SimpleLed(pub Output<'static>);
-
-impl super::traits::RgbLed for SimpleLed {
-    async fn set_rgb(&mut self, r: u8, g: u8, b: u8) {
-        if r > 0 || g > 0 || b > 0 {
-            self.0.set_high();
-        } else {
-            self.0.set_low();
-        }
-    }
-}
-
-pub type LedDriver = SimpleLed;
 
 pub type DisplayDriver = crate::driver::sh1106::Sh1106<DisplayI2c>;
 
@@ -148,7 +134,7 @@ impl LoRaBoard for Board {
 
         // Green LED on P1.01
         let led_pin = Output::new(p.P1_01, Level::Low, OutputDrive::Standard);
-        let led = Some(SimpleLed(led_pin));
+        let led = crate::driver::simple_led::SimpleLed(led_pin);
 
         BoardParts {
             radio,

firmware/src/display.rs

@@ -109,7 +109,7 @@ fn render_current(
 #[task]
 pub async fn display_task(
     parts: DisplayParts,
-    mut led: Option<LedDriver>,
+    mut led: LedDriver,
     status: &'static StatusWatch,
     display_commands: &'static DisplayCommandChannel,
 ) {
@@ -176,7 +176,6 @@ pub async fn display_task(
                     let _ = display.flush().await;
 
                     // Brief LED blink: red on TX, green scaled by SNR on RX
-                    if let Some(ref mut led) = led {
                     if tx_packet {
                         led.set_rgb(32, 0, 0).await;
                         Timer::after_millis(50).await;
@@ -189,17 +188,14 @@ pub async fn display_task(
                     }
                 }
             }
-            }
             Either3::Second(cmd) => match cmd {
                 DisplayCommand::Off => {
                     state.disconnected = false;
                     state.display_on = false;
                     render::blank(&mut display);
                     let _ = display.flush().await;
-                    if let Some(ref mut led) = led {
                     led.set_rgb(0, 0, 0).await;
                 }
-                }
                 DisplayCommand::On => {
                     state.disconnected = false;
                     state.display_on = true;
@@ -213,10 +209,8 @@ pub async fn display_task(
                     state = DisplayState::new();
                     render::splash(&mut display, &board_info);
                     let _ = display.flush().await;
-                    if let Some(ref mut led) = led {
                     led.set_rgb(0, 0, 0).await;
                 }
-                }
             },
             Either3::Third(()) => {
                 // Timer tick: advance sparkline slot

firmware/src/driver/mod.rs

@@ -1,2 +1,5 @@
 #[cfg(feature = "wio_tracker_l1")]
 pub mod sh1106;
+
+#[cfg(any(feature = "heltec_v3", feature = "heltec_v3_uart", feature = "heltec_v4", feature = "wio_tracker_l1"))]
+pub mod simple_led;

firmware/src/driver/simple_led.rs

@@ -0,0 +1,20 @@
+//! Simple single-color LED driver (GPIO on/off).
+//!
+//! Generic over any `OutputPin`. Any non-zero RGB value turns the LED on;
+//! all zeros turns it off.
+
+use embedded_hal::digital::OutputPin;
+
+use crate::board::RgbLed;
+
+pub struct SimpleLed<P>(pub P);
+
+impl<P: OutputPin> RgbLed for SimpleLed<P> {
+    async fn set_rgb(&mut self, r: u8, g: u8, b: u8) {
+        if r > 0 || g > 0 || b > 0 {
+            let _ = self.0.set_high();
+        } else {
+            let _ = self.0.set_low();
+        }
+    }
+}