[PATCH 3.18 09/13] hwmon: (lm80) Fix missing unlock on error in set_fan_div()

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Wei Yongjun <weiyongj...@huawei.com>

commit 07bd14ccc3049f9c0147a91a4227a571f981601a upstream.

Add the missing unlock before return from function set_fan_div()
in the error handling case.

Fixes: c9c63915519b ("hwmon: (lm80) fix a missing check of the status of SMBus 
read")
Signed-off-by: Wei Yongjun <weiyongj...@huawei.com>
Signed-off-by: Guenter Roeck <li...@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/hwmon/lm80.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/hwmon/lm80.c
+++ b/drivers/hwmon/lm80.c
@@ -393,8 +393,10 @@ static ssize_t set_fan_div(struct device
        }
 
        rv = lm80_read_value(client, LM80_REG_FANDIV);
-       if (rv < 0)
+       if (rv < 0) {
+               mutex_unlock(&data->update_lock);
                return rv;
+       }
        reg = (rv & ~(3 << (2 * (nr + 1))))
            | (data->fan_div[nr] << (2 * (nr + 1)));
        lm80_write_value(client, LM80_REG_FANDIV, reg);