1 files changed, 12 insertions, 22 deletions

diff --git a/drivers/char/nozomi.c b/drivers/char/nozomi.c
index cd405bcf53a6..fac9157a0ec0 100644
--- a/drivers/char/nozomi.c
+++ b/drivers/char/nozomi.c
@@ -1693,15 +1693,7 @@ static int ntty_write(struct tty_struct *tty, const unsigned char *buffer,
         if (!dc || !port)
                 return -ENODEV;
 
-        if (unlikely(!mutex_trylock(&port->tty_sem))) {
-                /*
-                 * must test lock as tty layer wraps calls
-                 * to this function with BKL
-                 */
-                dev_err(&dc->pdev->dev, "Would have deadlocked - "
-                        "return EAGAIN\n");
-                return -EAGAIN;
-        }
+        mutex_lock(&port->tty_sem);
 
         if (unlikely(!port->port.count)) {
                 DBG1(" ");
@@ -1741,25 +1733,23 @@ exit:
  * This method is called by the upper tty layer.
  *   #according to sources N_TTY.c it expects a value >= 0 and
  *    does not check for negative values.
+ *
+ * If the port is unplugged report lots of room and let the bits
+ * dribble away so we don't block anything.
  */
 static int ntty_write_room(struct tty_struct *tty)
 {
         struct port *port = tty->driver_data;
-        int room = 0;
+        int room = 4096;
         const struct nozomi *dc = get_dc_by_tty(tty);
 
-        if (!dc || !port)
-                return 0;
-        if (!mutex_trylock(&port->tty_sem))
-                return 0;
-
-        if (!port->port.count)
-                goto exit;
-
-        room = port->fifo_ul.size - kfifo_len(&port->fifo_ul);
-
-exit:
-        mutex_unlock(&port->tty_sem);
+        if (dc) {
+                mutex_lock(&port->tty_sem);
+                if (port->port.count)
+                        room = port->fifo_ul.size -
+                                        kfifo_len(&port->fifo_ul);
+                mutex_unlock(&port->tty_sem);
+        }
         return room;
 }