Book Image

Linux Device Driver Development - Second Edition

By : John Madieu
Book Image

Linux Device Driver Development - Second Edition

By: John Madieu

Overview of this book

Linux is by far the most-used kernel on embedded systems. Thanks to its subsystems, the Linux kernel supports almost all of the application fields in the industrial world. This updated second edition of Linux Device Driver Development is a comprehensive introduction to the Linux kernel world and the different subsystems that it is made of, and will be useful for embedded developers from any discipline. You'll learn how to configure, tailor, and build the Linux kernel. Filled with real-world examples, the book covers each of the most-used subsystems in the embedded domains such as GPIO, direct memory access, interrupt management, and I2C/SPI device drivers. This book will show you how Linux abstracts each device from a hardware point of view and how a device is bound to its driver(s). You’ll also see how interrupts are propagated in the system as the book covers the interrupt processing mechanisms in-depth and describes every kernel structure and API involved. This new edition also addresses how not to write device drivers using user space libraries for GPIO clients, I2C, and SPI drivers. By the end of this Linux book, you’ll be able to write device drivers for most of the embedded devices out there.
Table of Contents (23 chapters)
1
Section 1 -Linux Kernel Development Basics
6
Section 2 - Linux Kernel Platform Abstraction and Device Drivers
12
Section 3 - Making the Most out of Your Hardware
18
Section 4 - Misc Kernel Subsystems for the Embedded World

Learning some Linux kernel programming tips

Linux kernel development is about learning from others and not reinventing the wheel. There is a set of rules to follow when doing kernel development. A whole chapter won't be enough to cover these rules. Thus, I picked two of the most relevant to me, those that are likely to change when programming for user space: error handling and message printing.

In user space, exiting from the main() method is enough to recover from all the errors that may have occurred. In the kernel, this is not the case, especially since it directly deals with the hardware. Things are different for message printing as well, and we will see that in this section.

Error handling

Returning the wrong error code for a given error can result in either the kernel or user space application misinterpreting and taking the wrong decision, producing unneeded behavior. To keep things clear, there are predefined errors in the kernel tree that cover almost every case...