Using a Custom function which takes filename as input in Matlab Function Block, Simulink.

I have a written a matlab funcion which takes in a CSV data file and does some processing to give out 3 distinct tables as output.

I want to use it in Simulink so, I selected a Matlab Function Block and added the function there. The input for the function has to be a Filename. But, I didnt find any way where I can pass the filename as input(string).

Is there a way to pass that file name as input to the function block, for it to run the embedded matlab function further?

If this is not the right way then please suggest me how to go about this.

I need to have a simulink model which would ask for the file and does the processing as written in the matlab script.