Book Image

Mastering Linux Device Driver Development

By : John Madieu
Book Image

Mastering Linux Device Driver Development

By: John Madieu

Overview of this book

Linux is one of the fastest-growing operating systems around the world, and in the last few years, the Linux kernel has evolved significantly to support a wide variety of embedded devices with its improved subsystems and a range of new features. With this book, you’ll find out how you can enhance your skills to write custom device drivers for your Linux operating system. Mastering Linux Device Driver Development provides complete coverage of kernel topics, including video and audio frameworks, that usually go unaddressed. You’ll work with some of the most complex and impactful Linux kernel frameworks, such as PCI, ALSA for SoC, and Video4Linux2, and discover expert tips and best practices along the way. In addition to this, you’ll understand how to make the most of frameworks such as NVMEM and Watchdog. Once you’ve got to grips with Linux kernel helpers, you’ll advance to working with special device types such as Multi-Function Devices (MFD) followed by video and audio device drivers. By the end of this book, you’ll be able to write feature-rich device drivers and integrate them with some of the most complex Linux kernel frameworks, including V4L2 and ALSA for SoC.
Table of Contents (19 chapters)
1
Section 1:Kernel Core Frameworks for Embedded Device Driver Development
6
Section 2: Multimedia and Power Saving in Embedded Linux Systems
13
Section 3: Staying Up to Date with Other Linux Kernel Subsystems

Chapter 1: Linux Kernel Concepts for Embedded Developers

As a standalone software, the Linux kernel implements a set of functions that help not to reinvent the wheel and ease device driver developments. The importance of these helpers is that it’s not a requirement to use these for code to be accepted upstream. This is the kernel core that drivers rely on. We’ll cover the most popular of these core functionalities in this book, though other ones also exist. We will begin by looking at the kernel locking API before discussing how to protect shared objects and avoid race conditions. Then, we will look at various work deferring mechanisms available, where you will learn what part of the code to defer in which execution context. Finally, you will learn how interrupts work and how to design interrupt handlers from within the Linux kernel.

This chapter will cover the following topics:

  • The kernel locking API and shared objects
  • Work deferring mechanisms
  • Linux kernel interrupt management

Let’s get started!