Writing Linux Device Drivers is designed to show experienced programmers how to develop device drivers for Linux systems, and give them a basic understanding and familiarity with the Linux kernel. Upon mastering this material, you will be familiar with the different kinds of device drivers used under Linux, and know the appropriate API's through which devices (both hard and soft) interface with the kernel. The purpose is to get you into coding as quickly as possible. Thus we'll tell you early on how to dynamically allocate memor y in the simplest way, so you can actually write code, and then later cover the subject more thoroughly. Each section has exercises, most of which involve writing code, designed to help you gain familiarity with programming for the Linux kernel. Solutions are provided. We are not aiming for an expert audience, but instead for a competent and motivated one.