Sorry to ask you that but where can I find such a FT2232 dongle?
But maybe this device contains a FT2232 with EEPROM? I don't know. I don't want to mess around with the programming hardware because I would rather invest my time in building the board, I just want something that works without a lot of workarounds.
You don't need to "manually" program the EEPROM, the memory is just there to store VID/PID and configuration parameters for the chip itself, to set its modes... ie: UART, FIFO, SPI, I2C, JTAG emulators etc..
FTDI's FTDIprog utility provides a nice GUI to set it up.
If I read correctly, the FT2232 is a USB/UART converter (http://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT2232D.pdf) - I have a USB/UART converter with a CH340 chip here, would this one also work?
The FT2232 is dual UART/FIFO USB bridge, where each channel can be UART, FIFO, and one of them has hardware support for SPI and JTAG. With standard USB-UART bridges, the only way to do JTAG would be to bit bang (possible with the FT232) but it is much slower and of course you have to write the code for the API. I'm unsure if the CH340 has bit banging capability.
There is a special IDE for the iCE40-Series from Lattice: iCEcube 2
I've been on about JTAG but the FT2232C also does SPI, and is a common choice on a number of FPGA boards (for either JTAG, SPI for flash, or both). I have also seen it on a few 'iCE' dev boards so I can only assume it is supported by iCEcube 2. Example:
http://www.latticesemi.com/icestickAs to the availability of the FT2232C, I haven't really kept up on FTDI's range, it could be no longer supported for all I know - I just remember knocking up a cheap dev board for it and have been using it to config Lattice and Xilinx devices ever since.