add split_ref for stm32 uart

embassy-stm32/src/usart/buffered.rs

@@ -396,6 +396,13 @@ impl<'d> BufferedUart<'d> {
         (self.tx, self.rx)
     }
 
+    /// Split the Uart into a transmitter and receiver by mutable reference,
+    /// which is particularly useful when having two tasks correlating to
+    /// transmitting and receiving.
+    pub fn split_ref(&mut self) -> (&mut BufferedUartTx<'d>, &mut BufferedUartRx<'d>) {
+        (&mut self.tx, &mut self.rx)
+    }
+
     /// Reconfigure the driver
     pub fn set_config(&mut self, config: &Config) -> Result<(), ConfigError> {
         reconfigure(self.rx.info, self.rx.kernel_clock, config)?;

embassy-stm32/src/usart/mod.rs

@@ -1440,6 +1440,13 @@ impl<'d, M: Mode> Uart<'d, M> {
         (self.tx, self.rx)
     }
 
+    /// Split the Uart into a transmitter and receiver by mutable reference,
+    /// which is particularly useful when having two tasks correlating to
+    /// transmitting and receiving.
+    pub fn split_ref(&mut self) -> (&mut UartTx<'d, M>, &mut UartRx<'d, M>) {
+        (&mut self.tx, &mut self.rx)
+    }
+
     /// Send break character
     pub fn send_break(&self) {
         self.tx.send_break();