Essential Linux Device Drivers

by Venkateswaran, Sreekrishnan

• ISBN13: 9780132396554
• ISBN10: 0132396556
• Edition: 1st
• Format: Hardcover
• Copyright: 2008-03-27
• Publisher: Prentice Hall

Summary

"Probably the most wide ranging and complete Linux device driver book Irs"ve read." --Alan Cox, Linux Guru and Key Kernel Developer "Very comprehensive and detailed, covering almost every single Linux device driver type." --Theodore Tsrs"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 todayrs"s kernels, what once required years of development time can be accomplished in days. In this practical, example-driven book, one of the worldrs"s most experienced Linux driver developers systematically demonstrates how to develop reliable Linux drivers for virtually any device.Essential Linux Device Driversis 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 Linuxone of todayrs"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. bull; Addresses drivers discussed in no other book, including drivers for I2C, video, sound, PCMCIA, and different types of flash memory bull; Demystifies essential kernel services and facilities, including kernel threads and helper interfaces bull; Teaches polling, asynchronous notification, and I/O control bull; Introduces the Inter-Integrated Circuit Protocol for embedded Linux drivers bull; Covers multimedia device drivers using the Linux-Video subsystem and Linux-Audio framework bull; Shows how Linux implements support for wireless technologies such as Bluetooth, Infrared, WiFi, and cellular networking bull; Describes the entire driver development lifecycle, through debugging and maintenance bull; Includes reference appendixes covering Linux assembly, BIOS calls, and Seq files

Author Biography

Sreekrishnan Venkateswaran has spent more than a decade working in IBM product development laboratories. He has ported Linux to devices ranging from wristwatches and music players to PDAs, VoIP phones, and even pacemaker programmers. He was a Contributing Editor and kernel columnist for Linux Magazine for more than two years.

Table of Contents

Foreword
Preface
Acknowledgments	p. xxix
About the Author	p. xxx
Introduction	p. 1
Evolution	p. 2
The GNU Copyleft	p. 3
Kernelorg	p. 4
Mailing Lists and Forums	p. 4
Linux Distributions	p. 5
Looking at the Sources	p. 6
Building the Kernel	p. 10
Loadable Modules	p. 12
Before Starting	p. 14
A Peek Inside the Kernel	p. 17
Booting Up	p. 18
Kernel Mode and User Mode	p. 30
Process Context and Interrupt Context	p. 30
Kernel Timers	p. 31
HZ and Jiffies	p. 31
Long Delays	p. 33
Short Delays	p. 36
Pentium Time Stamp Counter	p. 36
Real Time Clock	p. 37
Concurrency in the Kernel	p. 39
Spinlocks and Mutexes	p. 39
Atomic Operators	p. 45
Reader-Writer Locks	p. 46
Debugging	p. 48
Process Filesystem	p. 49
Allocating Memory	p. 49
Looking at the Sources	p. 52
Kernel Facilities	p. 55
Kernel Threads	p. 56
Creating a Kernel Thread	p. 56
Process States and Wait Queues	p. 61
User Mode Helpers	p. 63
Helper Interfaces	p. 65
Linked Lists	p. 65
Hash Lists	p. 72
Work Queues	p. 72
Notifier Chains	p. 74
Completion Interface	p. 78
Kthread Helpers	p. 81
Error-Handling Aids	p. 83
Looking at the Sources	p. 85
Laying the Groundwork	p. 89
Introducing Devices and Drivers	p. 90
Interrupt Handling	p. 92
Interrupt Context	p. 92
Assigning IRQs	p. 94
Device Example: Roller Wheel	p. 94
Softirqs and Tasklets	p. 99
The Linux Device Model	p. 103
Udev	p. 103
Sysfs, Kobjects, and Device Classes	p. 106
Hotplug and Coldplug	p. 110
Microcode Download	p. 111
Module Autoload	p. 112
Memory Barriers	p. 114
Power Management	p. 114
Looking at the Sources	p. 115
Character Drivers	p. 119
Char Driver Basics	p. 120
Device Example: System CMOS	p. 121
Driver Initialization
Open and Release
Exchanging Data
Seek
Control
Sensing Data Availability
Poll
Fasync
Talking to the Parallel Port
Device Example: Parallel Port LED Board
RTC Subsystem
Pseudo Char Drivers
Misc Drivers
Device Example: Watchdog Timer
Character Caveats
Looking at the Sources
6556_Bookindb i6556_ix 3/4/08 9:31:21 AM
Serial Drivers	p. 171
Layered Architecture	p. 173
UART Drivers	p. 176
Device Example: Cell Phone	p. 178
RS-485	p. 191
TTY Drivers	p. 192
Line Disciplines	p. 194
Device Example: Touch Controller	p. 195
Looking at the Sources	p. 205
Input Drivers	p. 207
Input Event Drivers	p. 210
The Evdev Interface	p. 210
Input Device Drivers	p. 216
Serio	p. 217
Keyboards	p. 217
Mice	p. 220
Touch Controllers	p. 227
Accelerometers	p. 228
Output Events	p. 228
Debugging	p. 230
Looking at the Sources	p. 231
The Inter-Integrated Circuit Protocol	p. 233
Whats I2C/SMBus?	p. 234
I2C Core	p. 235
Bus Transactions	p. 237
Device Example: EEPROM	p. 238
Initializing	p. 238
Probing the Device	p. 241
Checking Adapter Capabilities	p. 244
Accessing the Device	p. 244
More Methods	p. 246
Device Example: Real Time Clock	p. 247
I2C-dev	p. 251
Hardware Monitoring Using LM-Sensors	p. 251
The Serial Peripheral Interface Bus	p. 251
The 1-Wire Bus	p. 254
Debugging	p. 254
Looking at the Sources	p. 255
PCMCIA and Compact Flash	p. 257
Whats PCMCIA/CF?	p. 258
Linux-PCMCIA Subsystem	p. 260
Host Controller Drivers	p. 262
PCMCIA Core	p. 263
Driver Services	p. 263
Client Drivers	p. 264
Data Structures	p. 264
Device Example: PCMCIA Card	p. 267
Tying the Pieces Together	p. 271
PCMCIA Storage	p. 272
Serial PCMCIA	p. 272
Debugging	p. 273
Looking at the Sources	p. 275
Peripheral Comp
Table of Contents provided by Publisher. All Rights Reserved.

Excerpts

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