serial: 8250: Refactor serial8250_rx_chars() inner loop

Factor the read/process one char inner loop to a separate helper
function serial8250_read_char(). No functional change.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_port.c

@@ -1412,20 +1412,12 @@ static void serial8250_enable_ms(struct uart_port *port)
 	serial8250_rpm_put(up);
 }
 
-/*
- * serial8250_rx_chars: processes according to the passed in LSR
- * value, and returns the remaining LSR bits not handled
- * by this Rx routine.
- */
-unsigned char
-serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
+static void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr)
 {
 	struct uart_port *port = &up->port;
 	unsigned char ch;
-	int max_count = 256;
-	char flag;
+	char flag = TTY_NORMAL;
 
-	do {
 	if (likely(lsr & UART_LSR_DR))
 		ch = serial_in(up, UART_RX);
 	else
@@ -1438,7 +1430,6 @@ serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
 		 */
 		ch = 0;
 
-		flag = TTY_NORMAL;
 	port->icount.rx++;
 
 	lsr |= up->lsr_saved_flags;
@@ -1455,7 +1446,7 @@ serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
 			 * or read_status_mask.
 			 */
 			if (uart_handle_break(port))
-					goto ignore_char;
+				return;
 		} else if (lsr & UART_LSR_PE)
 			port->icount.parity++;
 		else if (lsr & UART_LSR_FE)
@@ -1477,11 +1468,24 @@ serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
 			flag = TTY_FRAME;
 	}
 	if (uart_handle_sysrq_char(port, ch))
-			goto ignore_char;
+		return;
 
 	uart_insert_char(port, lsr, UART_LSR_OE, ch, flag);
+}
 
-ignore_char:
+/*
+ * serial8250_rx_chars: processes according to the passed in LSR
+ * value, and returns the remaining LSR bits not handled
+ * by this Rx routine.
+ */
+unsigned char
+serial8250_rx_chars(struct uart_8250_port *up, unsigned char lsr)
+{
+	struct uart_port *port = &up->port;
+	int max_count = 256;
+
+	do {
+		serial8250_read_char(up, lsr);
 		lsr = serial_in(up, UART_LSR);
 	} while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (--max_count > 0));
 	spin_unlock(&port->lock);