Don't expose DLAB.

Author: qwandor

uart8250/src/uart.rs

@@ -113,11 +113,15 @@ impl<'a> MmioUart8250<'a> {
     /// | 115200    | 1                    | $00                     | $01                    |
     #[inline]
     pub fn set_divisor(&self, clock: usize, baud_rate: usize) {
-        self.enable_divisor_latch_accessible();
+        // Enable DLAB.
+        self.reg.lcr.modify(LCR::DLAB::SET);
+
         let divisor = clock / (16 * baud_rate);
         self.reg.thr_rbr_dll.set(divisor as u8);
         self.reg.ier_dlh.set((divisor >> 8) as u8);
-        self.disable_divisor_latch_accessible();
+
+        // Disable DLAB.
+        self.reg.lcr.modify(LCR::DLAB::CLEAR);
     }
 
     /// Get IER bitflags
@@ -284,21 +288,6 @@ impl<'a> MmioUart8250<'a> {
         !self.reg.iir_fcr.is_set(IIR::InterruptPending)
     }
 
-    /// get whether DLAB is enabled
-    pub fn is_divisor_latch_accessible(&self) -> bool {
-        self.reg.lcr.read(LCR::DLAB) != 0
-    }
-
-    /// enable DLAB
-    pub fn enable_divisor_latch_accessible(&self) {
-        self.reg.lcr.modify(LCR::DLAB::SET)
-    }
-
-    /// disable DLAB
-    pub fn disable_divisor_latch_accessible(&self) {
-        self.reg.lcr.modify(LCR::DLAB::CLEAR)
-    }
-
     /// get parity of used data protocol
     pub fn get_parity(&self) -> Parity {
         self.reg
@@ -453,7 +442,6 @@ mod tests {
         assert!(matches!(uart.get_parity(), Parity::No));
         assert_eq!(uart.get_stop_bit(), 1);
         assert_eq!(uart.get_word_length(), 8);
-        assert_eq!(uart.is_divisor_latch_accessible(), false);
     }
 
     #[test]