[PATCH 4.20 28/32] hwmon: (lm80) Fix missing unlock on error in set_fan_div()

[Greg Kroah-Hartman]

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

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

[ Upstream commit 07bd14ccc3049f9c0147a91a4227a571f981601a ]

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 <weiyongjun1@xxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/hwmon/lm80.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/hwmon/lm80.c b/drivers/hwmon/lm80.c
index 0e30fa00204cd..f9b8e3e23a8e8 100644
--- a/drivers/hwmon/lm80.c
+++ b/drivers/hwmon/lm80.c
@@ -393,8 +393,10 @@ static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr,
 	}
 
 	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);
-- 
2.19.1