How to make cell editable dynamically in jqGrid

I am new to jqGrid and I need help with a scenario that I am not able to figure out.

I am able to make a cell un-editable using the following code:

jQuery("#updAssist").jqGrid('setCell',rowid,'precPsProg','','not-editable-cell');

Now I want to make the cell editable again based on some condition.

What class should I use to achieve that?

Is there a 'editable-cell' class that I can use?