amba-pl011: Don't send a character during startup

This causes a corrupted character to be sent and
there's no explanation for why it is required.

If it worked correctly it would send an extra 0x00
which isn't appropriate either.

Signed-off-by: Simon Arlott <sa.me.uk>

Author: nomis

drivers/tty/serial/amba-pl011.c

@@ -1393,6 +1393,11 @@ static int pl011_startup(struct uart_port *port)
 
 	writew(uap->vendor->ifls, uap->port.membase + UART011_IFLS);
 
+	/*
+	 * The write to UART01x_DR causes a corrupted character to be sent
+	 * - why is it required?
+	 */
+#if 0
 	/*
 	 * Provoke TX FIFO interrupt into asserting.
 	 */
@@ -1414,6 +1419,7 @@ static int pl011_startup(struct uart_port *port)
 	writew(0, uap->port.membase + UART01x_DR);
 	while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
 		barrier();
+#endif
 
 	cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
 	writew(cr, uap->port.membase + UART011_CR);