Hi,
1)If your input control can be applied on the report level than at the chart level then you can use the function ReportFilter([Sales Person]) to get the filter value applied on the sales person object at the report level.
2)If not then you need to derive it as mentioned in below link
Display Input Control Values on Report | Michael’s BI Safari
3)If you want a work around then create a vertical table and remove the header of it and place sales person name field in this table.
And make this table also as the dependent block of your input control. so that it will display only the values that is selected. It will work if you single selection for your input control