[PATCH] TTY: hvcs: fix missing unlock on error in hvcs_initialize()

[Wei Yongjun]

From: Wei Yongjun <yongjun_wei at trendmicro.com.cn>

Add the missing unlock on the error handling path in function
hvcs_initialize().

Signed-off-by: Wei Yongjun <yongjun_wei at trendmicro.com.cn>
---
 drivers/tty/hvc/hvcs.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
index cab5c7a..744c3b8 100644
--- a/drivers/tty/hvc/hvcs.c
+++ b/drivers/tty/hvc/hvcs.c
@@ -1496,8 +1496,10 @@ static int __devinit hvcs_initialize(void)
 		num_ttys_to_alloc = hvcs_parm_num_devs;
 
 	hvcs_tty_driver = alloc_tty_driver(num_ttys_to_alloc);
-	if (!hvcs_tty_driver)
+	if (!hvcs_tty_driver) {
+		mutex_unlock(&hvcs_init_mutex);
 		return -ENOMEM;
+	}
 
 	if (hvcs_alloc_index_list(num_ttys_to_alloc)) {
 		rc = -ENOMEM;