TTY: ami_serial, remove BTM from wait_until_sent

The same as in "TTY: serial, remove BTM from wait_until_sent" we don't
need to take BTM in wait_until_sent of ami_serial. Exactly the same
as serial, ami_serial accesses some "info" members (xmit_fifo_size,
timeout), but their assignment on other places in the code is not
protected by BTM anyway.

So the BTM protects nothing here. This removal helps us to get rid of
tty_locked() and __big_tty_mutex_owner in the following patch. This
was suggested by Arnd.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Andreas Bombe <aeb@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 9 deletions

diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c
index 220579592c20..6d43f550b549 100644
--- a/drivers/tty/amiserial.c
+++ b/drivers/tty/amiserial.c
@@ -1529,7 +1529,6 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
 {
         struct async_struct * info = tty->driver_data;
         unsigned long orig_jiffies, char_time;
-        int tty_was_locked = tty_locked();
         int lsr;
 
         if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent"))
@@ -1541,12 +1540,6 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
         orig_jiffies = jiffies;
 
         /*
-         * tty_wait_until_sent is called from lots of places,
-         * with or without the BTM.
-         */
-        if (!tty_was_locked)
-                tty_lock();
-        /*
          * Set the check interval to be 1/5 of the estimated time to
          * send a single character, and make it at least 1.  The check
          * interval should also be less than the timeout.
@@ -1586,8 +1579,7 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
                         break;
         }
         __set_current_state(TASK_RUNNING);
-        if (!tty_was_locked)
-                tty_unlock();
+
 #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
         printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
 #endif