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Overview Overview Essential Linux Device Drivers by Sreekrishnan Venkateswaran Publisher: Prentice Hall Pub Date: March 27, 2008 Print ISBN-10: 0-13-239655-6 Print ISBN-13: 978-0-13-239655-4 Pages: 744 Table of Contents | Index Overview "Probably the most wide ranging and complete Linux device driver book I've read." --Alan Cox, Linux Guru and Key Kernel Developer "Very comprehensive and detailed, covering almost every single Linux device driver type." --Theodore Ts'o, First Linux Kernel Developer in North America and Chief Platform Strategist of the Linux Foundation The Most Practical Guide to Writing Linux Device Drivers Linux now offers an exceptionally robust environment for driver development: with today's kernels, what once required years of development time can be accomplished in days. In this practical, example-driven book, one of the world's most experienced Linux driver developers systematically demonstrates how to develop reliable Linux drivers for virtually any device. Essential Linux Device Drivers is for any programmer with a working knowledge of operating systems and C, including programmers who have never written drivers before. Sreekrishnan Venkateswaran focuses on the essentials, bringing together all the concepts and techniques you need, while avoiding topics that only matter in highly specialized situations. Venkateswaran begins by reviewing the Linux 2.6 kernel capabilities that are most relevant to driver developers. He introduces simple device classes; then turns to serial buses such as I2C and SPI; external buses such as PCMCIA, PCI, and USB; video, audio, block, network, and wireless device drivers; user-space drivers; and drivers for embedded Linux–one of today's fastest growing areas of Linux development. For each, Venkateswaran explains the technology, inspects relevant kernel source files, and walks through developing a complete example. • Addresses drivers discussed in no other book, including drivers for I2C, video, sound, PCMCIA, and different types of flash memory • Demystifies essential kernel services and facilities, including kernel threads and helper interfaces • Teaches polling, asynchronous notification, and I/O control • Introduces the Inter-Integrated Circuit Protocol for embedded Linux drivers • Covers multimedia device drivers using the Linux-Video subsystem and Linux-Audio framework • Shows how Linux implements support for wireless technologies such as Bluetooth, Infrared, WiFi, and cellular networking • Describes the entire driver development lifecycle, through debugging and maintenance • Includes reference appendixes covering Linux assembly, BIOS calls, and Seq files Essential Linux Device Drivers by Sreekrishnan Venkateswaran Publisher: Prentice Hall Pub Date: March 27, 2008 Print ISBN-10: 0-13-239655-6 Print ISBN-13: 978-0-13-239655-4 Pages: 744 Table of Contents | Index Copyright Prentice Hall Open Source Software Development Series Foreword Preface Acknowledgments About the Author Chapter 1. Introduction Evolution The GNU Copyleft Kernel.org Mailing Lists and Forums Linux Distributions Looking at the Sources Building the Kernel Loadable Modules Before Starting Chapter 2. A Peek Inside the Kernel Booting Up Kernel Mode and User Mode Process Context and Interrupt Context Kernel Timers Concurrency in the Kernel Process Filesystem Allocating Memory Looking at the Sources Chapter 3. Kernel Facilities Kernel Threads Helper Interfaces Looking at the Sources Chapter 4. Laying the Groundwork Introducing Devices and Drivers Interrupt Handling The Linux Device Model Memory Barriers Power Management Looking at the Sources Chapter 5. Character Drivers Char Driver Basics Device Example: System CMOS Sensing Data Availability Talking to the Parallel Port RTC Subsystem Pseudo Char Drivers Misc Drivers Character Caveats Looking at the Sources Chapter 6. Serial Drivers Layered Architecture UART Drivers TTY Drivers Line Disciplines Looking at the Sources Chapter 7. Input Drivers Input Event Drivers Input Device Drivers Debugging Looking at the Sources Chapter 8. The Inter-Integrated Circuit Protocol What's I2C/SMBus? I2C Core Bus Transactions Device Example: EEPROM Device Example: Real Time Clock I2C-dev Hardware Monitoring Using LM-Sensors The Serial Peripheral Interface Bus The 1-Wire Bus Debugging Looking at the Sources Chapter 9. PCMCIA and Compact Flash What's PCMCIA/CF? Linux-PCMCIA Subsystem Host Controller Drivers PCMCIA Core Driver Services Client Drivers Tying the Pieces Together PCMCIA Storage Serial PCMCIA Debugging Looking at the Sources Chapter 10. Peripheral Component Interconnect The PCI Family Addressing and Identification Accessing PCI Regions Direct Memory Access Device Example: Ethernet-Modem Card Debugging Looking at the Sources Chapter 11. Universal Serial Bus USB Architecture Linux-USB Subsystem Driver Data Structures Enumeration Device Example: Telemetry Card Class Drivers Gadget Drivers Debugging Looking at the Sources Chapter 12. Video Drivers Display Architecture Linux-Video Subsystem Display Parameters The Frame Buffer API Frame Buffer Drivers Console Drivers Debugging Looking at the Sources Chapter 13. Audio Drivers Audio Architecture Linux-Sound Subsystem Device Example: MP3 Player Debugging Looking at the Sources Chapter 14. Block Drivers Storage Technologies Linux Block I/O Layer I/O Schedulers Block Driver Data Structures and Methods Device Example: Simple Storage Controller Advanced Topics Debugging Looking at the Sources Chapter 15. Network Interface Cards Driver Data Structures Talking with Protocol Layers Buffer Management and Concurrency Control Device Example: Ethernet NIC ISA Network Drivers Asynchronous Transfer Mode Network Throughput Looking at the Sources Chapter 16. Linux Without Wires Bluetooth Infrared WiFi Cellular Networking Current Trends Chapter 17. Memory Technology Devices What's Flash Memory? Linux-MTD Subsystem Map Drivers NOR Chip Drivers NAND Chip Drivers User Modules MTD-Utils Configuring MTD eXecute In Place The Firmware Hub Debugging Looking at the Sources Chapter 18. Embedding Linux Challenges Component Selection Tool Chains Embedded Bootloaders Memory Layout Kernel Porting Embedded Drivers The Root Filesystem Test Infrastructure Debugging Chapter 19. Drivers in User Space Process Scheduling and Response Times Accessing I/O Regions Accessing Memory Regions User Mode SCSI User Mode USB User Mode I2C UIO Looking at the Sources Chapter 20. More Devices and Drivers ECC Reporting Frequency Scaling Embedded Controllers ACPI ISA and MCA FireWire Intelligent Input/Output Amateur Radio Voice over IP High-Speed Interconnects Chapter 21. Debugging Device Drivers Kernel Debuggers Kernel Probes Kexec and Kdump Profiling Tracing Linux Test Project User Mode Linux Diagnostic Tools Kernel Hacking Config Options Test Equipment Chapter 22. Maintenance and Delivery Coding Style Change Markers Version Control Consistent Checksums Build Scripts Portable Code Chapter 23. Shutting Down Checklist What Next? Appendix A. Linux Assembly Debugging Appendix B. Linux and the BIOS Real Mode Calls Protected Mode Calls BIOS and Legacy Drivers Appendix C. Seq Files The Seq File Advantage Updating the NVRAM Driver Looking at the Sources Index Copyright Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book, and the publisher was aware of a trademark claim, the designations have been printed with initial capital letters or in all capitals. The author and publisher have taken care in the preparation of this book, but make no expressed or implied warranty of any kind and assume no responsibility for errors or omissions. No liability is assumed for incidental or consequential damages in connection with or arising out of the use of the information or programs contained herein. The publisher offers excellent discounts on this book when ordered in quantity for bulk purchases or special sales, which may include electronic versions and/or custom covers and content particular to your business, training goals, marketing focus, and branding interests. For more information, please contact: U.S. Corporate and Government Sales (800) 382-3419 [email protected] For sales outside the United States please contact: International Sales [email protected] Visit us on the Web: www.informit.com/ph Library of Congress Cataloging-in-Publication Data: Venkateswaran, Sreekrishnan, 1972- Essential Linux device drivers / Sreekrishnan Venkateswaran.-- 1st ed. p. cm. ISBN 0-13-239655-6 (hardback : alk. paper) 1. Linux device drivers (Computer programs) I. Title. QA76.76.D49V35 2008 005.4'32--dc22 2008000249 Copyright © 2008 Pearson Education, Inc. All rights reserved. Printed in the United States of America. This publication is protected by copyright, and permission must be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or by any means, electronic, mechanical, photocopying, recording, or likewise. For information regarding permissions, write to: Pearson Education, Inc Rights and Contracts Department 501 Boylston Street, Suite 900 Boston, MA 02116 Fax (617) 671 3447 This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at http://www.opencontent.org/openpub/). ISBN-13: 978-0-132-39655-4 Text printed in the United States on recycled paper at RR Donnelly in Crawfordsville, IN. First printing March
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