SERCOM Status/Flags from TryFrom impl to fn

The TryFrom approach resulted in warnings, following Rust updates aimed
at stabilizing the never type.

rust-lang/rust#123748

hal/src/sercom/spi.rs

@@ -398,15 +398,18 @@ bitflags! {
     }
 }
 
-/// Convert [`Status`] flags into the corresponding [`Error`] variants
-impl TryFrom<Status> for () {
-    type Error = Error;
+impl Status {
+    /// Check whether [`Self`] originates from an error.
+    ///
+    /// # Errors
+    ///
+    /// Returns an error if `STATUS` contains `BUFOVF` or `LENERR`
     #[inline]
-    fn try_from(status: Status) -> Result<(), Error> {
+    pub fn check_bus_error(self) -> Result<(), Error> {
         // Buffer overflow has priority
-        if status.contains(Status::BUFOVF) {
+        if self.contains(Status::BUFOVF) {
             Err(Error::Overflow)
-        } else if status.contains(Status::LENERR) {
+        } else if self.contains(Status::LENERR) {
             Err(Error::LengthError)
         } else {
             Ok(())

hal/src/sercom/spi/reg.rs

@@ -340,7 +340,7 @@ impl<S: Sercom> Registers<S> {
     /// Try to read the interrupt flags, but first check the error status flags.
     #[inline]
     pub fn read_flags_errors(&self) -> Result<Flags, Error> {
-        self.read_status().try_into()?;
+        self.read_status().check_bus_error()?;
         Ok(self.read_flags())
     }
 }

hal/src/sercom/uart.rs

@@ -910,7 +910,7 @@ where
     /// containing the corresponding [`Flags`] or [`Error`]
     #[inline]
     fn read_flags_errors(&self) -> Result<Flags, Error> {
-        self.read_status().try_into()?;
+        self.read_status().check_bus_error()?;
         Ok(self.read_flags())
     }
 

hal/src/sercom/uart/flags.rs

@@ -91,21 +91,30 @@ pub enum Error {
     CollisionDetected,
 }
 
-impl TryFrom<Status> for () {
-    type Error = Error;
-
+impl Status {
+    /// Check whether [`Self`] originates from an error.
+    ///
+    /// # Errors
+    ///
+    /// Returns an error if `STATUS` contains:
+    ///
+    /// * `PERR` - Parity Error
+    /// * `FERR` - Frame Error
+    /// * `BUFOVF` - Buffer Overflow
+    /// * `ISF` - Inconsistent Sync Field
+    /// * `COLL` - Collision Detected
     #[inline]
-    fn try_from(errors: Status) -> Result<(), Error> {
+    pub fn check_bus_error(self) -> Result<(), Error> {
         use Error::*;
-        if errors.contains(Status::PERR) {
+        if self.contains(Status::PERR) {
             Err(ParityError)
-        } else if errors.contains(Status::FERR) {
+        } else if self.contains(Status::FERR) {
             Err(FrameError)
-        } else if errors.contains(Status::BUFOVF) {
+        } else if self.contains(Status::BUFOVF) {
             Err(Overflow)
-        } else if errors.contains(Status::ISF) {
+        } else if self.contains(Status::ISF) {
             Err(InconsistentSyncField)
-        } else if errors.contains(Status::COLL) {
+        } else if self.contains(Status::COLL) {
             Err(CollisionDetected)
         } else {
             Ok(())