Explore the process of implementing a custom USB device controller driver in Zephyr RTOS through this informative 30-minute conference talk. Delve into Mohammed Billoo's experience integrating a driver for a custom USB device controller implemented in an FPGA with the Zephyr USB stack. Learn about the challenges encountered, necessary workarounds, and valuable lessons learned during the implementation process. Gain insights into the system architecture, USB CDC in FreeRTOS, TinyUSB, and the existing system. Understand the problem statement, device connection, USB transactions, packets, endpoints, and enumeration. Follow the speaker's initial strategy, troubleshooting efforts, and the resolution achieved. Conclude with a retrospective analysis and discover the next steps for this project, equipping yourself with practical knowledge for custom driver development in Zephyr.