From: eLinux.org
An Open Source EZ-USB SDK is available at http://www.ztex.de/firmware-kit.
It is mainly intended for our ZTEX FPGA Boards but should run on every EZ-USB based hardware. The package currently runs under Linux and Windows.
The Firmware is written in C and requires the SDCC compiler. A macro approach allows to configure the Firmware easily using macro commands. The necessary USB descriptors and the descriptor handling routines are generated automatically.
The driver API is written in Java and allows platform independent device drivers. Alternatively the USB devices can be accessed through a web and a socket interface using the device server.