Linux Device Drivers
Linux Device Drivers, Third Edition
Christopher Jonathan Corbet, Alessandro Rubini, Greg Kroah-Hartman, O'Reilly Media, Inc, ISBN 13: 9780596005900
Adding Jonathan Corbet as author.
Second edition of this book is freely available online.
It details the 2.4 kernel series.
The third edition, adding Greg Kroah-Hartman as an author discusses driver development for the 2.6.10 kernel.
This book also is freely available online. Please consider buying the "dead tree" version to support the authors.