Book Image

Linux Device Driver Development Cookbook

By : Rodolfo Giometti
Book Image

Linux Device Driver Development Cookbook

By: Rodolfo Giometti

Overview of this book

Linux is a unified kernel that is widely used to develop embedded systems. As Linux has turned out to be one of the most popular operating systems worldwide, the interest in developing proprietary device drivers has also increased. Device drivers play a critical role in how the system performs and ensure that the device works in the manner intended. By exploring several examples on the development of character devices, the technique of managing a device tree, and how to use other kernel internals, such as interrupts, kernel timers, and wait queue, you’ll be able to add proper management for custom peripherals to your embedded system. You’ll begin by installing the Linux kernel and then configuring it. Once you have installed the system, you will learn to use different kernel features and character drivers. You will also cover interrupts in-depth and understand how you can manage them. Later, you will explore the kernel internals required for developing applications. As you approach the concluding chapters, you will learn to implement advanced character drivers and also discover how to write important Linux device drivers. By the end of this book, you will be equipped with the skills you need to write a custom character driver and kernel code according to your requirements.
Table of Contents (14 chapters)
10
Additional Information: Managing Interrupts and Concurrency

Using kernel messages

As already stated, the serial console is very helpful if we need to set up a system from scratch, but it's also very useful if we wish to see kernel messages as soon as they are generated. In order to generate kernel messages, we can use several functions and, in this recipe, we will take a look at them and how to display messages on the serial console or over an SSH connection.

Getting ready

Our ESPRESSObin is the system that generates kernel messages, so we need a connection to it. Through the serial console, these messages are automatically displayed as soon as they arrive, but if we are using an SSH connection, we can still display them by reading specific files, as with the following command...