[PATCH] backlight: (adp8870) fix a missing check for adp8870_write

[Kangjie Lu]

adp8870_write() may fail. This fix checks if adp8870_write fails, and if
so, returns its error code.

Signed-off-by: Kangjie Lu <kjlu@xxxxxxx>
---
 drivers/video/backlight/adp8870_bl.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/video/backlight/adp8870_bl.c b/drivers/video/backlight/adp8870_bl.c
index 8d50e0299578..79901fb4fcd1 100644
--- a/drivers/video/backlight/adp8870_bl.c
+++ b/drivers/video/backlight/adp8870_bl.c
@@ -811,9 +811,14 @@ static ssize_t adp8870_bl_ambient_light_zone_store(struct device *dev,
 		if (!ret) {
 			reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
 			reg_val |= (val - 1) << CFGR_BLV_SHIFT;
-			adp8870_write(data->client, ADP8870_CFGR, reg_val);
-		}
-		mutex_unlock(&data->lock);
+			ret = adp8870_write(data->client,
+					ADP8870_CFGR, reg_val);
+			if (ret) {
+				mutex_unlock(&data->lock);
+				return ret;
+			}
+		}	else
+			mutex_unlock(&data->lock);
 	}
 
 	return count;
-- 
2.17.2 (Apple Git-113)