Book Linux Device Drivers, 3rd Edition in pure HTML format. Available for html linkage to each chapter. For example Network Drivers, Quick Reference

This book is available under the terms of the Creative Commons Attribution-ShareAlike 2.0 license. That means that you are free to download and redistribute it. The development of the book was made possible, however, by those who purchase a copy from O'Reilly or elsewhere.

Linux Device Drivers, Third Edition, in Internet, PDF version of the book: http://lwn.net/Kernel/LDD3/, http://www.oreilly.com/catalog/linuxdrive3/book/

Linux Device Drivers, 2nd Edition: http://www.xml.com/ldd/chapter/book/