refactor nfc reader code a bit

src/bin/main.rs

@@ -7,13 +7,13 @@
 )]
 #![deny(clippy::large_stack_frames)]
 
-use alloc::boxed::Box;
 use creaturedex::card::decoder::split_nfc_hex;
 use creaturedex::card::model::Card;
+use creaturedex::drivers::i2c_bus::I2cBusPinConfiguration;
+use creaturedex::drivers::nfc_pn532::NfcPn532Driver;
 use creaturedex::drivers::secondary_oled::SecondaryDisplay;
 use creaturedex::drivers::spi_bus;
 use creaturedex::drivers::tertiary_lcd::{TertiaryDisplay, init_tertiary_lcd, write_wrapped};
-use creaturedex::drivers::nfc_pn532::NfcPn532Driver;
 use creaturedex::navigation::inputs::Inputs;
 use creaturedex::navigation::navigation::{self, CARD_DATA};
 use creaturedex::navigation::outputs::Outputs;
@@ -27,11 +27,10 @@ use embedded_graphics::{
     text::Text,
 };
 use embedded_hal_bus::i2c::AtomicDevice;
-use embedded_hal_bus::util::AtomicCell;
 use esp_hal::Blocking;
 use esp_hal::clock::CpuClock;
 use esp_hal::gpio::{Input, InputConfig, Pull};
-use esp_hal::i2c::master::{Config as I2cConfig, I2c};
+use esp_hal::i2c::master::I2c;
 use esp_hal::timer::timg::TimerGroup;
 use log::error;
 
@@ -82,18 +81,15 @@ async fn main(spawner: Spawner) {
     }
     .build();
 
-    let config = I2cConfig::default().with_frequency(esp_hal::time::Rate::from_khz(400));
-    let i2c = match I2c::new(peripherals.I2C0, config) {
-        Ok(bus) => bus
-            .with_sda(peripherals.GPIO17)
-            .with_scl(peripherals.GPIO18),
-        Err(e) => {
-            log::error!("Shared I2C bus initialization failed for GPIO17/GPIO18: {e:?}");
-            panic!("Shared I2C bus initialization failed");
-        }
+    // Initialize the shared I2C bus using the refactored i2c_bus module.
+    let shared_i2c = {
+        let config = I2cBusPinConfiguration {
+            i2c_peripheral: peripherals.I2C0,
+            scl: peripherals.GPIO18,
+            sda: peripherals.GPIO17,
+        };
+        config.build()
     };
-    let shared_i2c = Box::leak(Box::new(AtomicCell::new(i2c)));
-    log::info!("Shared I2C bus ready on GPIO17 (SDA) and GPIO18 (SCL)");
 
     let mut lcd: TertiaryDisplay = init_tertiary_lcd(AtomicDevice::new(shared_i2c));
     if let Err(e) = write_wrapped(&mut lcd, "Testing more than 16 chars what happens now?") {

src/drivers/nfc_pn532.rs

@@ -1,4 +1,5 @@
 use alloc::vec::Vec;
+use core::error::Error;
 use embedded_hal::i2c::I2c;
 use log::{error, info};
 use pn532::i2c::I2CInterface;
@@ -8,6 +9,7 @@ use pn532::{Pn532, Request};
 pub type Pn532Device<I2C> = Pn532<I2CInterface<I2C>, (), 34>;
 
 pub const PAGES_PER_READ: usize = 4;
+pub const BYTES_PER_READ: usize = PAGES_PER_READ * 4;
 
 /// PN532 NFC reader driver.
 pub struct NfcPn532Driver<I2C>
@@ -17,6 +19,35 @@ where
     pn532: Pn532Device<I2C>,
 }
 
+#[derive(Debug, Clone)]
+struct PageParseError<const N: usize> {
+    iteration: u8,
+    bytes: [u8; N],
+    status_code: Option<u8>,
+}
+
+impl<const N: usize> Error for PageParseError<N> {}
+
+impl<const N: usize> core::fmt::Display for PageParseError<N> {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        let PageParseError {
+            iteration,
+            bytes,
+            status_code,
+        } = self;
+        match status_code {
+            Some(code) => write!(
+                f,
+                "NFC pages parse error in iteration {iteration} with error code 0x{code:02x}: {bytes:02x?}"
+            ),
+            None => write!(
+                f,
+                "No data available for NFC page in iteration {iteration}: {bytes:02x?}"
+            ),
+        }
+    }
+}
+
 impl<I2C> NfcPn532Driver<I2C>
 where
     I2C: I2c,
@@ -57,16 +88,21 @@ where
         }
     }
 
-    pub fn parse_nfc_page(iteration: u8, bytes: &[u8]) -> Result<[u8; PAGES_PER_READ * 4], ()> {
-        let success = bytes.first().is_some_and(|x| *x == 0);
-        if success {
-            let slice_len = bytes.len().min(PAGES_PER_READ * 4 + 1);
-            let mut arr = [0; PAGES_PER_READ * 4];
-            arr[..slice_len - 1].copy_from_slice(&bytes[1..slice_len]);
-            Ok(arr)
-        } else {
-            info!("err  {iteration}: {:02x?}", bytes);
-            Err(())
+    fn parse_nfc_page(
+        iteration: u8,
+        bytes: &[u8],
+    ) -> Result<[u8; BYTES_PER_READ], PageParseError<BYTES_PER_READ>> {
+        let slice_len = bytes.len().min(BYTES_PER_READ + 1);
+        let mut arr = [0; BYTES_PER_READ];
+        arr[..slice_len - 1].copy_from_slice(&bytes[1..slice_len]);
+
+        match bytes.first() {
+            Some(0x00) => Ok(arr),
+            error => Err(PageParseError {
+                iteration,
+                bytes: arr,
+                status_code: error.copied(),
+            }),
         }
     }
 
@@ -79,18 +115,25 @@ where
         let mut data: Vec<u8> = Vec::with_capacity(858);
 
         for i in (0x0B..=230).step_by(PAGES_PER_READ) {
-            let mut parse_result = Err(());
-            while parse_result.is_err() {
-                let Ok(result) = self
+            let bytes = loop {
+                let read = self
                     .pn532
-                    .process_async(&Request::ntag_read(i), PAGES_PER_READ * 4 + 1)
-                    .await
-                else {
-                    continue;
+                    .process_async(&Request::ntag_read(i), BYTES_PER_READ + 1)
+                    .await;
+
+                let bytes = match read {
+                    Ok(bytes) => bytes,
+                    Err(e) => {
+                        error!("Reading page {i} failed: {e:?}");
+                        continue;
+                    }
                 };
-                parse_result = Self::parse_nfc_page(i, result);
-            }
-            let bytes = parse_result.unwrap();
+
+                match Self::parse_nfc_page(i, bytes) {
+                    Ok(data) => break data,
+                    Err(e) => error!("Parsing page failed: {e}"),
+                }
+            };
             let bytes = if i == 0x0B { &bytes[1..] } else { &bytes };
             data.extend(bytes);
         }

todo.txt

@@ -1,5 +0,0 @@
-- init of all OLEDs
-- struct for pins
-- sharedbus -> spibus -> driver
-- i2c bus -> drivers
-- spidevice with config -> different clocks?