Fix poor & unimplemented code

src/lib.rs

@@ -129,7 +129,7 @@ impl <'c, SPI: Transfer<u8>,
         rx_packet.update_frame_length();
         // Read frame bytes
         let mut frame_buf = [0; rx::RAW_FRAME_LENGTH_MAX];
-        self.spi_port.read_rxdat(&mut frame_buf, rx_packet.get_frame_length() as u32)?;
+        self.spi_port.read_rxdat(&mut frame_buf, rx_packet.get_frame_length())?;
         rx_packet.copy_frame_from(&frame_buf[1..]);
         // Set ERXTAIL pointer to (next_addr - 2)
         if self.rx_buf.get_next_addr() > rx::ERXST_DEFAULT {
@@ -152,7 +152,7 @@ impl <'c, SPI: Transfer<u8>,
         // 1-byte Opcode is included 
         let mut txdat_buf: [u8; tx::RAW_FRAME_LENGTH_MAX + 1] = [0; tx::RAW_FRAME_LENGTH_MAX + 1];
         packet.write_frame_to(&mut txdat_buf[1..]);
-        self.spi_port.write_txdat(&mut txdat_buf, packet.get_frame_length() as u32)?;
+        self.spi_port.write_txdat(&mut txdat_buf, packet.get_frame_length())?;
         // Set ETXST to packet start address
         self.spi_port.write_reg_16b(spi::addrs::ETXST, self.tx_buf.get_next_addr())?;
         // Set ETXLEN to packet length

src/spi.rs

@@ -1,10 +1,7 @@
-use core::fmt;
 use embedded_hal::{
     blocking::spi::Transfer,
     digital::v2::OutputPin,
-    spi,
 };
-use crate::rx;
 
 pub mod interfaces {
     use embedded_hal::spi;
@@ -64,6 +61,7 @@ pub enum SpiPortError {
     TransferError
 }
 
+#[allow(unused_must_use)]
 impl <SPI: Transfer<u8>, 
       NSS: OutputPin> SpiPort<SPI, NSS> {
     // TODO: return as Result()
@@ -78,19 +76,19 @@ impl <SPI: Transfer<u8>,
 
     pub fn read_reg_8b(&mut self, addr: u8) -> Result<u8, SpiPortError> {
         // Using RCRU instruction to read using unbanked (full) address
-        let mut r_data = self.rw_addr_u8(opcodes::RCRU, addr, 0)?;
+        let r_data = self.rw_addr_u8(opcodes::RCRU, addr, 0)?;
         Ok(r_data)
     }
 
     pub fn read_reg_16b(&mut self, lo_addr: u8) -> Result<u16, SpiPortError> {
-        let mut r_data_lo = self.read_reg_8b(lo_addr)?;
-        let mut r_data_hi = self.read_reg_8b(lo_addr + 1)?;
+        let r_data_lo = self.read_reg_8b(lo_addr)?;
+        let r_data_hi = self.read_reg_8b(lo_addr + 1)?;
         // Combine top and bottom 8-bit to return 16-bit
         Ok(((r_data_hi as u16) << 8) | r_data_lo as u16)
     }
 
     // Currently requires manual slicing (buf[1..]) for the data read back
-    pub fn read_rxdat<'a>(&mut self, buf: &'a mut [u8], data_length: u32) 
+    pub fn read_rxdat<'a>(&mut self, buf: &'a mut [u8], data_length: usize) 
                          -> Result<(), SpiPortError> {
         let r_valid = self.r_n(buf, opcodes::RERXDATA, data_length)?;
         Ok(r_valid)
@@ -98,7 +96,7 @@ impl <SPI: Transfer<u8>,
 
     // Currenly requires actual data to be stored in buf[1..] instead of buf[0..]
     // TODO: Maybe better naming?
-    pub fn write_txdat<'a>(&mut self, buf: &'a mut [u8], data_length: u32) 
+    pub fn write_txdat<'a>(&mut self, buf: &'a mut [u8], data_length: usize) 
                           -> Result<(), SpiPortError> {
         let w_valid = self.w_n(buf, opcodes::WEGPDATA, data_length)?;
         Ok(w_valid)
@@ -137,7 +135,7 @@ impl <SPI: Transfer<u8>,
                 Ok(buf[2])
             },
             // TODO: Maybe too naive?
-            Err(e) => {
+            Err(_) => {
                 // Disable chip select
                 self.nss.set_high();
                 Err(SpiPortError::TransferError)
@@ -150,20 +148,20 @@ impl <SPI: Transfer<u8>,
     // Returns a reference to the data returned
     // Note: buf must be at least (data_length + 1)-byte long
     // TODO: Check and raise error for array size < (data_length + 1)
-    fn r_n<'a>(&mut self, buf: &'a mut [u8], opcode: u8, data_length: u32) 
+    fn r_n<'a>(&mut self, buf: &'a mut [u8], opcode: u8, data_length: usize) 
               -> Result<(), SpiPortError> {
         // Enable chip select
         self.nss.set_low();
         // Start writing to SLAVE
         buf[0] = opcode;
-        match self.spi.transfer(buf) {
+        match self.spi.transfer(&mut buf[..data_length+1]) {
             Ok(_) => {
                 // Disable chip select
                 self.nss.set_high();
                 Ok(())
             },
             // TODO: Maybe too naive?
-            Err(e) => {
+            Err(_) => {
                 // Disable chip select
                 self.nss.set_high();
                 Err(SpiPortError::TransferError)
@@ -173,21 +171,21 @@ impl <SPI: Transfer<u8>,
 
     // Note: buf[0] is currently reserved for opcode to overwrite
     // TODO: Actual data should start from buf[0], not buf[1]
-    fn w_n<'a>(&mut self, buf: &'a mut [u8], opcode: u8, data_length: u32) 
+    fn w_n<'a>(&mut self, buf: &'a mut [u8], opcode: u8, data_length: usize) 
               -> Result<(), SpiPortError> {
         // Enable chip select
         self.nss.set_low();
         // Start writing to SLAVE
         buf[0] = opcode;
         // TODO: Maybe need to copy data to buf later on
-        match self.spi.transfer(buf) {
+        match self.spi.transfer(&mut buf[..data_length+1]) {
             Ok(_) => {
                 // Disable chip select
                 self.nss.set_high();
                 Ok(())
             },
             // TODO: Maybe too naive?
-            Err(e) => {
+            Err(_) => {
                 // Disable chip select
                 self.nss.set_high();
                 Err(SpiPortError::TransferError)