USB: keyspan: fix overrun-error reporting

commit 855515a6 upstream.

Fix reporting of overrun errors, which are not associated with a
character. Instead insert a null character and report only once.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
[lizf: Backported to 3.4:
 - s/&port->port/tty
 - adjust context
 - adjust indentation]
Signed-off-by: Zefan Li <lizefan@huawei.com>

drivers/usb/serial/keyspan.c

@@ -323,12 +323,11 @@ static void	usa26_indat_callback(struct urb *urb)
 		if ((data[0] & 0x80) == 0) {
 			/* no errors on individual bytes, only
 			   possible overrun err */
-			if (data[0] & RXERROR_OVERRUN)
-				err = TTY_OVERRUN;
-			else
-				err = 0;
+			if (data[0] & RXERROR_OVERRUN) {
+				tty_insert_flip_char(tty, 0, TTY_OVERRUN);
+			}
 			for (i = 1; i < urb->actual_length ; ++i)
-				tty_insert_flip_char(tty, data[i], err);
+				tty_insert_flip_char(tty, data[i], TTY_NORMAL);
 		} else {
 			/* some bytes had errors, every byte has status */
 			dbg("%s - RX error!!!!", __func__);
@@ -859,13 +858,13 @@ static void usa90_indat_callback(struct urb *urb)
 			if ((data[0] & 0x80) == 0) {
 				/* no errors on individual bytes, only
 				   possible overrun err*/
-				if (data[0] & RXERROR_OVERRUN)
-					err = TTY_OVERRUN;
-				else
-					err = 0;
+				if (data[0] & RXERROR_OVERRUN) {
+					tty_insert_flip_char(tty, 0,
+								TTY_OVERRUN);
+				}
 				for (i = 1; i < urb->actual_length ; ++i)
 					tty_insert_flip_char(tty, data[i],
-									err);
+								TTY_NORMAL);
 			}  else {
 			/* some bytes had errors, every byte has status */
 				dbg("%s - RX error!!!!", __func__);