Recover from init fail

src/bin/main.rs

@@ -64,7 +64,9 @@ async fn main(spawner: Spawner) {
     let timg0 = TimerGroup::new(peripherals.TIMG0);
     esp_rtos::start(timg0.timer0, sw_interrupt.software_interrupt0);
 
-    let (primary, mut secondaries) = spi_bus::DisplayPinConfiguration {
+    let (primary, mut secondaries) = retry(
+        5,
+        spi_bus::DisplayPinConfiguration {
             spi_peripheral: peripherals.SPI2,
             sck: peripherals.GPIO36,
             mosi: peripherals.GPIO35,
@@ -76,20 +78,26 @@ async fn main(spawner: Spawner) {
             reset_primary: peripherals.GPIO10,
             reset_secondary: peripherals.GPIO47,
             dc_pin: peripherals.GPIO12,
-    }
+        },
-    .build();
+        spi_bus::DisplayPinConfiguration::build,
+    );
 
     // Initialize the shared I2C bus using the refactored i2c_bus module.
     let shared_i2c = {
-        let config = I2cBusPinConfiguration {
+        use alloc::boxed::Box;
+        let bus = retry(5, I2cBusPinConfiguration {
             i2c_peripheral: peripherals.I2C0,
             scl: peripherals.GPIO18,
             sda: peripherals.GPIO17,
-        };
+        }, I2cBusPinConfiguration::build);
-        config.build()
+        Box::leak(Box::new(bus))
     };
 
-    let mut lcd: TertiaryDisplay = TertiaryDisplayPinConfiguration { i2c: shared_i2c }.build();
+    let mut lcd: TertiaryDisplay = retry(
+        5,
+        TertiaryDisplayPinConfiguration { i2c: shared_i2c },
+        TertiaryDisplayPinConfiguration::build,
+    );
     lcd.load_charset(EXAMPLE).unwrap();
     let h = EXAMPLE[HEART];
     let e = EXAMPLE[EMPTY];
@@ -140,6 +148,7 @@ async fn main(spawner: Spawner) {
     log::info!("Setup complete, entering main loop");
     spawner.spawn(navigation::run(inputs, outputs).expect("run task failed"));
     spawner.spawn(background_tasks::nfc_scanner(nfc_driver).expect("nfc scanner task failed"));
+    core::future::pending::<()>().await
 }
 
 fn display_shit(oled: &mut SecondaryDisplay<'static>, text: &str) {
@@ -151,3 +160,17 @@ fn display_shit(oled: &mut SecondaryDisplay<'static>, text: &str) {
         .unwrap();
     oled.flush().unwrap();
 }
+
+fn retry<T, U, F: FnMut(T) -> Result<U, T>>(repetitions: u32, input: T, mut action: F) -> U {
+    let mut initial_state = input;
+    for iteration in 0..repetitions {
+        log::debug!("Trying to initialize. Retries: {iteration}");
+
+        match action(initial_state) {
+            Ok(success) => return success,
+            Err(recovered_input) => initial_state = recovered_input,
+        }
+    }
+
+    panic!("Init failed after {repetitions} retries.")
+}

src/drivers/i2c_bus.rs

@@ -1,4 +1,3 @@
-use alloc::boxed::Box;
 use embedded_hal_bus::i2c::AtomicDevice;
 use embedded_hal_bus::util::AtomicCell;
 use esp_hal::gpio::interconnect::PeripheralInput;
@@ -21,18 +20,19 @@ where
     SCL: PeripheralOutput<'a> + PeripheralInput<'a>,
     SDA: PeripheralOutput<'a> + PeripheralInput<'a>,
 {
-    pub fn build(self) -> I2cBus<'a> {
+    pub fn build(self) -> Result<AtomicCell<InnerI2cBus<'a>>, Self> {
         let config = Config::default().with_frequency(esp_hal::time::Rate::from_khz(400));
-        let i2c = match I2c::new(self.i2c_peripheral, config) {
+        match I2c::new(self.i2c_peripheral, config) {
-            Ok(bus) => bus.with_sda(self.sda).with_scl(self.scl),
+            Ok(bus) => {
+                let i2c = bus.with_sda(self.sda).with_scl(self.scl);
+                log::info!("Shared I2C bus ready on GPIO17 (SDA) and GPIO18 (SCL)");
+                Ok(AtomicCell::new(i2c))
+            }
             Err(e) => {
                 log::error!("Shared I2C bus initialization failed for GPIO17/GPIO18: {e:?}");
-                panic!("Shared I2C bus initialization failed");
+                unimplemented!("Partial move makes it impossible to retry.");
-            }
+                // Err(self)
-        };
+            }
-        let shared_i2c = Box::leak(Box::new(AtomicCell::new(i2c)));
+        }
-        log::info!("Shared I2C bus ready on GPIO17 (SDA) and GPIO18 (SCL)");
-
-        shared_i2c
     }
 }

src/drivers/spi_bus.rs

@@ -135,7 +135,7 @@ where
     RES2: OutputPin + 'static,
     DC: OutputPin + 'static,
 {
-    pub fn build(self) -> (PrimaryDisplay<'static>, [SecondaryDisplay<'static>; 3]) {
+    pub fn build(self) -> Result<(PrimaryDisplay<'static>, [SecondaryDisplay<'static>; 3]), Self> {
         let spi = Spi::new(
             self.spi_peripheral,
             SpiConfig::default()
@@ -178,7 +178,7 @@ where
         }
         .build();
 
-        (primary, secondaries)
+        Ok((primary, secondaries))
     }
 }
 

src/drivers/tertiary_lcd.rs

@@ -15,19 +15,20 @@ pub struct TertiaryDisplayPinConfiguration<'a> {
 }
 
 impl<'a> TertiaryDisplayPinConfiguration<'a> {
-    pub fn build(self) -> TertiaryDisplay<'a> {
+    pub fn build(self) -> Result<TertiaryDisplay<'a>, Self> {
         let device = AtomicDevice::new(self.i2c);
         let mut lcd = CharacterDisplayPCF8574T::new(device, LcdDisplayType::Lcd16x2, Delay::new());
         match lcd.init() {
             Ok(()) => {
                 log::info!("I2C tertiary LCD initialized on PCF8574T at address 0x27");
-                TertiaryDisplay {
+                Ok(TertiaryDisplay {
                     display: lcd,
                     charset: create_custom_char_set!(),
-                }
+                })
             }
             Err(e) => {
-                panic!("I2C tertiary LCD init failed on PCF8574T at address 0x27: {e}");
+                log::error!("I2C tertiary LCD init failed on PCF8574T at address 0x27: {e}");
+                Err(self)
             }
         }
     }
@@ -407,4 +408,3 @@ pub const BOX: CharMap = [
 ];
 
 pub const EXAMPLE: CustomCharset = create_custom_char_set!(HEART, BOX, EMPTY);
-