If you are talking about 3dsmax's auto smoothing, which is basically changing the smoothing angle of the normals of the surface. An equivalent of that in maya would be under >Edit Polygons>Normals>soften/harden. In the option, you can adjust what angle you want (the greater the angle, the smoother it is).
If you are refering to smoothing out the geometry by moving vertices and not creating new geometry, then you have a few options in Maya. Average vertices can do this and also artisan's smooth tool can be use to overall smooth the model.