Organisation of the Material

The book introduces its topics in ascending order of complexity and is divided into two parts. The first part (Chapters 1-11) begins with the proper setup of kernel modules and goes on to describe the various aspects of programming that you'll need in order to write a full-featured driver for a char-oriented device. Every chapter covers a distinct problem and includes a quick summary at the end, which can be used as a reference during actual development.
Throughout the first part of the book, the organization of the material moves roughly from the software-oriented concepts to the hardware-related ones. This organization is meant to allow you to test the software on your own computer as far as possible without the need to plug external hardware into the machine. Every chapter includes source code and points to sample drivers that you can run on any Linux computer. In Chapter 9 and Chapter 10, however, we ask you to connect an inch of wire to the parallel port in order to test out hardware handling, but this requirement should be manageable by everyone.
The second half of the book (Chapters 12-18) describes block drivers and network interfaces and goes deeper into more advanced topics, such as working with the virtual memory subsystem and with the PCI and USB buses. Many driver authors do not need all of this material, but we encourage you to go on reading anyway. Much of the material found there is interesting as a view into how the Linux kernel works, even if you do not need it for a specific project.