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

Building a Linux kernel module

Two solutions exist for compiling a kernel module:

  • The first solution is when code is outside of the kernel source tree, which is also known as out-of-tree building. The module source code is in a different directory. Building a module this way does not allow integration into the kernel configuration/compilation process, and the module needs to be built separately. It must be noted that with this solution, the module cannot be statically linked in the final kernel image – that is, it cannot be built in. Out-of-tree compilation only allows loadable kernel modules to be produced.
  • The second solution is inside the kernel tree, which allows you to upstream your code, since it is well integrated into the kernel configuration/compilation process. This solution allows you to produce either a statically linked module (also known as built-in) or a loadable kernel module.

Now that we have enumerated and given the characteristics of the...