media: ov5640: fix wrong binning value in exposure calculation

ov5640_set_mode_exposure_calc() is checking binning value but
binning value read is buggy, fix this.
Rename ov5640_binning_on() to ov5640_get_binning() as per other
similar functions.

Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/i2c/ov5640.c

@@ -1383,7 +1383,7 @@ static int ov5640_set_ae_target(struct ov5640_dev *sensor, int target)
 	return ov5640_write_reg(sensor, OV5640_REG_AEC_CTRL1F, fast_low);
 }
 
-static int ov5640_binning_on(struct ov5640_dev *sensor)
+static int ov5640_get_binning(struct ov5640_dev *sensor)
 {
 	u8 temp;
 	int ret;
@@ -1391,8 +1391,8 @@ static int ov5640_binning_on(struct ov5640_dev *sensor)
 	ret = ov5640_read_reg(sensor, OV5640_REG_TIMING_TC_REG21, &temp);
 	if (ret)
 		return ret;
-	temp &= 0xfe;
-	return temp ? 1 : 0;
+
+	return temp & BIT(0);
 }
 
 static int ov5640_set_binning(struct ov5640_dev *sensor, bool enable)
@@ -1478,7 +1478,7 @@ static int ov5640_set_mode_exposure_calc(struct ov5640_dev *sensor,
 	if (ret < 0)
 		return ret;
 	prev_shutter = ret;
-	ret = ov5640_binning_on(sensor);
+	ret = ov5640_get_binning(sensor);
 	if (ret < 0)
 		return ret;
 	if (ret && mode->id != OV5640_MODE_720P_1280_720 &&