Linux Device Drivers, Second Edition

Acknowledgments

This book, of course, was not written in a vacuum; we would like to thank the many people who have helped to make it possible.

I (Alessandro) would like to thank the people that made this work possible. First of all, the incredible patience of Federica, who went as far as letting me review the first edition during our honeymoon, with a laptop in the tent. Giorgio and Giulia have only been involved in the second edition of the book, and helped me stay in touch with reality by eating pages, pulling wires, and crying for due attention. I must also thank all four grandparents, who came to the rescue when the deadlines were tight and took over my fatherly duties for whole days, letting me concentrate on code and coffee. I still owe a big thanks to Michael Johnson, who made me enter the world of writing. Even though this was several years ago, he’s still the one that made the wheel spin; earlier, I had left the university to avoid writing articles instead of software. Being an independent consultant, I have no employer that kindly allowed me to work on the book; on the other hand, I owe due acknowledgment to Francesco Magenta and Rodolfo Giometti, who are helping me as “dependent consultants.” Finally, I want to acknowledge the free-software authors who actually taught me how to program without even knowing me; this includes both kernel and user-space authors I enjoyed reading, but they are too many to list.

I (Jon) am greatly indebted to many people; first and foremost I wish to thank my wife, Laura, who put up with the great time demands of writing a book while simultaneously trying to make a “dotcom” business work. My children, Michele and Giulia, have been a constant source of joy and inspiration. Numerous people on the linux-kernel list showed great patience in answering my questions and setting me straight on things. My colleagues at LWN.net have been most patient with my distraction, and our readers’ support of the LWN kernel page has been outstanding. This edition probably would not have happened without the presence of Boulder’s local community radio station (appropriately named KGNU), which plays amazing music, and the Lake Eldora ski lodge, which allowed me to camp out all day with a laptop during my kids’ ski lessons and served good coffee. I owe gratitude to Evi Nemeth for first letting me play around in the early BSD source on her VAX, to William Waite for really teaching me to program, and to Rit Carbone of the National Center for Atmospheric Research (NCAR), who got me started on a long career where I learned almost everything else.

We both wish to thank our editor, Andy Oram; this book is a vastly better product as a result of his efforts. And obviously we owe a lot to the smart people who pushed the free-software idea and still keep it running (that’s mainly Richard Stallman, but he’s definitely not alone).

We have also been helped at the hardware level; we couldn’t study so many platforms without external help. We thank Intel for loaning an early IA-64 system, and Rebel.com for donating a Netwinder (their ARM-based tiny computer). Prosa Labs, the former Linuxcare-Italia, loaned a pretty fat PowerPC system; NEC Electronics donated their interesting development system for the VR4181 processor—that’s a palmtop where we could put a GNU/Linux system on flash memory. Sun-Italia loaned both a SPARC and a SPARC64 system. All of those companies and those systems helped keep Alessandro busy in debugging portability issues and forced him to get one more room to fit his zoo of disparate silicon beasts.

The first edition was technically reviewed by Alan Cox, Greg Hankins, Hans Lermen, Heiko Eissfeldt, and Miguel de Icaza (in alphabetic order by first name). The technical reviewers for the second edition were Allan B. Cruse, Christian Morgner, Jake Edge, Jeff Garzik, Jens Axboe, Jerry Cooperstein, Jerome Peter Lynch, Michael Kerrisk, Paul Kinzelman, and Raph Levien. Together, these people have put a vast amount of effort into finding problems and pointing out possible improvements to our writing.

Last but certainly not least, we thank the Linux developers for their relentless work. This includes both the kernel programmers and the user-space people, who often get forgotten. In this book we chose never to call them by name in order to avoid being unfair to someone we might forget. We sometimes made an exception to this rule and called Linus by name; we hope he doesn’t mind, though.