Interface and data trasfer between FPGA and Processor- TI AM4376 over USB2.0
So you said you can transfer data from USB host to FPGA through CY7C68014A bridge. Therefore your host must be using packet transactions of OUT type.

To get the data in opposite direction, USB uses IN transaction. Host sends "IN" packet, and device sends the data back if ready, or NAK when data not ready.

But I am really curious how did you manage to construct OUT transactions if you don't know what the IN is for.