Updated msg_type to be more readable

Author: ohunter

src/linux.rs

@@ -301,15 +301,15 @@ impl<'a> I2CTransfer<'a> for LinuxI2CDevice {
     /// Issue the provided sequence of I2C transactions
     fn transfer(&mut self, messages: &'a mut [Self::Message]) -> Result<u32, LinuxI2CError> {
         let msg_type = |flag: u16| flag & I2CMessageFlags::READ.bits();
-        let mut prev_msg_type = !msg_type(messages[0].flags);
+        let mut prev_msg_type = messages.first().map(|m| msg_type(m.flags));
         for msg in messages.iter_mut() {
             msg.addr = self.slave_address;
 
             let cur_msg_type = msg_type(msg.flags);
-            if prev_msg_type == cur_msg_type {
+            if prev_msg_type.is_some_and(|prev| prev == cur_msg_type) {
                 msg.flags |= I2CMessageFlags::NO_START.bits();
             } else {
-                prev_msg_type = cur_msg_type;
+                prev_msg_type = Some(cur_msg_type);
             }
         }
         ffi::i2c_rdwr(self.as_raw_fd(), messages).map_err(From::from)