serial: bfin-uart: Enable hardware automatic CTS only when CTS pin is available.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/tty/serial/bfin_uart.c

@@ -726,16 +726,17 @@ static int bfin_serial_startup(struct uart_port *port)
 	}
 #endif
 #ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
-	if (uart->cts_pin >= 0 && request_irq(uart->status_irq,
-		bfin_serial_mctrl_cts_int,
-		0, "BFIN_UART_MODEM_STATUS", uart)) {
-		uart->cts_pin = -1;
-		pr_info("Unable to attach BlackFin UART Modem Status interrupt.\n");
-	}
+	if (uart->cts_pin >= 0) {
+		if (request_irq(uart->status_irq, bfin_serial_mctrl_cts_int,
+			IRQF_DISABLED, "BFIN_UART_MODEM_STATUS", uart)) {
+			uart->cts_pin = -1;
+			dev_info(port->dev, "Unable to attach BlackFin UART Modem Status interrupt.\n");
+		}
 
-	/* CTS RTS PINs are negative assertive. */
-	UART_PUT_MCR(uart, ACTS);
-	UART_SET_IER(uart, EDSSI);
+		/* CTS RTS PINs are negative assertive. */
+		UART_PUT_MCR(uart, ACTS);
+		UART_SET_IER(uart, EDSSI);
+	}
 #endif
 
 	UART_SET_IER(uart, ERBFI);