Research And Application Of USB Driver Based On S3C2440A Embedded Linux System

With the rapid development of computer technology, appeared all kinds of bus, which include ISA, MCA, EISA, VESA, PCI and so on. USB (Universal Serial Bus) as a serial bus technology of wide application, which is more and more widely as a result of its development and application, thus, development USB driver will be became a trend in embedded system.Generally, USB HOST controls all transmission, moreover peripheral equipments (e.g. Android Smart phone, Digital Camera) as USB DEVICE realize different function. Because Embedded Linux operating system has the advantage of system performance stabilization, easy to transplantation, powerful network function, it becomes most popular open source operating system, and more and more project start with use Linux operating system. Android (based on Linux kernel) system is currently most popular development platform of smart phone, it has became tidal current in electronic product of consumption (mobile telephone, flat computer and so on).This project is based on S3C2440A (ARM920T kernel), Embedded Linux operating system and Android system, hardware platform makes demand for two interfaces (USB HOST and USB DEVICE). Android system accepts android-2.3.1-rl, Embedded Linux operating system adopts Linux-2.6.32.2kernel. However, S3C2440A supports2-port USB HOST and USB DEVICE interface, and it is compatible with USB specification version1.1.This paper discusses and research with emphasis embedded Linux operating system, Android system, the independent research and development of product S3C2440A in Samsung, which developing and realizing identification of USB Mass Storage device in Linux operating system, develop board simulation Digital U disk with ARM embedded Linux system, use ADB tool through USB in Android system. This function can be provided with more applied value.This paper emphasis statement from several of aspects:first, declare USB hardware interface circuit; second, describe USB protocol and USB driver total struct of Linux kernel; third, explain for details USB bus driver (USB HOST driver and USB device driver) of S3C2440A; finally, illustrate how realize USB Mass Storage device under USB HOST driver, and how realize USB Gadget device driver (File-storage Gadget driver and Android USB Gadget driver) under USB device drivers.