TTY: switch tty_insert_flip_string

Now, we start converting tty buffer functions to actually use
tty_port. This will allow us to get rid of the need of tty in many
call sites. Only tty_port will needed and hence no more
tty_port_tty_get in those paths.

tty_insert_flip_string this time.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/gadget/u_serial.c b/drivers/usb/gadget/u_serial.c
index d0f9548..3560799 100644
--- a/drivers/usb/gadget/u_serial.c
+++ b/drivers/usb/gadget/u_serial.c
@@ -495,12 +495,8 @@
 
 		req = list_first_entry(queue, struct usb_request, list);
 
-		/* discard data if tty was closed */
-		if (!tty)
-			goto recycle;
-
 		/* leave data queued if tty was rx throttled */
-		if (test_bit(TTY_THROTTLED, &tty->flags))
+		if (tty && test_bit(TTY_THROTTLED, &tty->flags))
 			break;
 
 		switch (req->status) {
@@ -533,7 +529,8 @@
 				size -= n;
 			}
 
-			count = tty_insert_flip_string(tty, packet, size);
+			count = tty_insert_flip_string(&port->port, packet,
+					size);
 			if (count)
 				do_push = true;
 			if (count != size) {
@@ -546,7 +543,7 @@
 			}
 			port->n_read = 0;
 		}
-recycle:
+
 		list_move(&req->list, &port->read_pool);
 		port->read_started--;
 	}