serial_txx9: Fix modem control line handling

This chip does not have modem control lines.  Return TIOCM_CAR and
TIOCM_DSR always on get_mctrl() and ajust some bits in termios cflag.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Acked-by: NAlan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/serial/serial_txx9.c

@@ -37,7 +37,7 @@
 
 #include <asm/io.h>
 
-static char *serial_version = "1.09";
+static char *serial_version = "1.10";
 static char *serial_name = "TX39/49 Serial driver";
 
 #define PASS_LIMIT	256
@@ -436,8 +436,10 @@ static unsigned int serial_txx9_get_mctrl(struct uart_port *port)
 	struct uart_txx9_port *up = (struct uart_txx9_port *)port;
 	unsigned int ret;
 
-	ret =  ((sio_in(up, TXX9_SIFLCR) & TXX9_SIFLCR_RTSSC) ? 0 : TIOCM_RTS)
-		| ((sio_in(up, TXX9_SICISR) & TXX9_SICISR_CTSS) ? 0 : TIOCM_CTS);
+	/* no modem control lines */
+	ret = TIOCM_CAR | TIOCM_DSR;
+	ret |= (sio_in(up, TXX9_SIFLCR) & TXX9_SIFLCR_RTSSC) ? 0 : TIOCM_RTS;
+	ret |= (sio_in(up, TXX9_SICISR) & TXX9_SICISR_CTSS) ? 0 : TIOCM_CTS;
 
 	return ret;
 }
@@ -557,6 +559,12 @@ serial_txx9_set_termios(struct uart_port *port, struct ktermios *termios,
 	unsigned long flags;
 	unsigned int baud, quot;
 
+	/*
+	 * We don't support modem control lines.
+	 */
+	termios->c_cflag &= ~(HUPCL | CMSPAR);
+	termios->c_cflag |= CLOCAL;
+
 	cval = sio_in(up, TXX9_SILCR);
 	/* byte size and parity */
 	cval &= ~TXX9_SILCR_UMODE_MASK;