diff --git a/src/ol/geom/flatgeom.js b/src/ol/geom/flatgeom.js
index 5915684be4..4b07535188 100644
--- a/src/ol/geom/flatgeom.js
+++ b/src/ol/geom/flatgeom.js
@@ -310,16 +310,13 @@ ol.geom.flat.lineStringInterpolate =
  * @param {number} offset Offset.
  * @param {number} end End.
  * @param {number} stride Stride.
- * @param {ol.geom.GeometryLayout} layout Layout.
  * @param {number} m M.
  * @param {boolean} extrapolate Extrapolate.
  * @return {ol.Coordinate} Coordinate.
  */
 ol.geom.flat.lineStringCoordinateAtM =
-    function(flatCoordinates, offset, end, stride, layout, m, extrapolate) {
-  if ((layout != ol.geom.GeometryLayout.XYM &&
-       layout != ol.geom.GeometryLayout.XYZM) ||
-      end == offset) {
+    function(flatCoordinates, offset, end, stride, m, extrapolate) {
+  if (end == offset) {
     return null;
   }
   var coordinate;
diff --git a/src/ol/geom/linestring.js b/src/ol/geom/linestring.js
index d97a316f6a..35988047bb 100644
--- a/src/ol/geom/linestring.js
+++ b/src/ol/geom/linestring.js
@@ -86,9 +86,13 @@ ol.geom.LineString.prototype.closestPointXY =
  * @return {ol.Coordinate} Coordinate.
  */
 ol.geom.LineString.prototype.getCoordinateAtM = function(m, opt_extrapolate) {
+  if (this.layout != ol.geom.GeometryLayout.XYM &&
+      this.layout != ol.geom.GeometryLayout.XYZM) {
+    return null;
+  }
   var extrapolate = goog.isDef(opt_extrapolate) ? opt_extrapolate : false;
   return ol.geom.flat.lineStringCoordinateAtM(this.flatCoordinates, 0,
-      this.flatCoordinates.length, this.stride, this.layout, m, extrapolate);
+      this.flatCoordinates.length, this.stride, m, extrapolate);
 };