The validation function from a column only has the value and the callback function as parameters (function (value, callback)). I can’t seem to find a way to get the row number for the validated value (and eventually the column number) since I have to correlate the validation of a cell with a value from another cell.
You can retrieve all information about edited cell using function context this. in you validation function. I’ve created demo at http://jsfiddle.net/budnix/55ovwtn0/ where you can see how to grab row and column when validation was triggered.