adv7341 sync inputs

Your part expects negative polarity syncs, except when the CEA861 bit is asserted. But what about when graphics standards video is input? How does the part handle VESA GTF or DMT sync polarities, which can vary in polarity? Does the user have to add logic to make the syncs negative going at all times? Or does asserting CEA861 mode make the part agnostic to polarities?