serial: drivers/serial/pmac_zilog.c: add missing unlock

In an error handling case the lock is not unlocked.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
expression E1;
identifier f;
@@

f (...) { <+...
* spin_lock_irqsave (E1,...);
... when != E1
* return ...;
...+> }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/serial/pmac_zilog.c b/drivers/serial/pmac_zilog.c
index 4eaa043ca2a8c40552eebb258b7d447ef6de2818..700e10833bf98965280491ba49771b1ad7c3d618 100644 (file)
--- a/drivers/serial/pmac_zilog.c
+++ b/drivers/serial/pmac_zilog.c
@@ -752,8 +752,10 @@ static void pmz_break_ctl(struct uart_port *port, int break_state)
                uap->curregs[R5] = new_reg;
 
                /* NOTE: Not subject to 'transmitter active' rule. */
-               if (ZS_IS_ASLEEP(uap))
+               if (ZS_IS_ASLEEP(uap)) {
+                       spin_unlock_irqrestore(&port->lock, flags);
                        return;
+               }
                write_zsreg(uap, R5, uap->curregs[R5]);
        }