media: ov2680: Don't take the lock for try_fmt calls

On ov2680_set_fmt() calls with format->which == V4L2_SUBDEV_FORMAT_TRY,
ov2680_set_fmt() does not talk to the sensor.

So in this case there is no need to lock the sensor->lock mutex or
to check that the sensor is streaming.

Fixes: 3ee47cad ("media: ov2680: Add Omnivision OV2680 sensor driver")
Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/i2c/ov2680.c

@@ -595,24 +595,22 @@ static int ov2680_set_fmt(struct v4l2_subdev *sd,
 	if (format->pad != 0)
 		return -EINVAL;
 
-	mutex_lock(&sensor->lock);
-
-	if (sensor->is_streaming) {
-		ret = -EBUSY;
-		goto unlock;
-	}
-
 	mode = v4l2_find_nearest_size(ov2680_mode_data,
 				      ARRAY_SIZE(ov2680_mode_data), width,
 				      height, fmt->width, fmt->height);
-	if (!mode) {
-		ret = -EINVAL;
-		goto unlock;
-	}
+	if (!mode)
+		return -EINVAL;
 
 	if (format->which == V4L2_SUBDEV_FORMAT_TRY) {
 		try_fmt = v4l2_subdev_get_try_format(sd, sd_state, 0);
 		format->format = *try_fmt;
+		return 0;
+	}
+
+	mutex_lock(&sensor->lock);
+
+	if (sensor->is_streaming) {
+		ret = -EBUSY;
 		goto unlock;
 	}