Book Image

Linux Device Drivers Development

By : John Madieu
Book Image

Linux Device Drivers Development

By: John Madieu

Overview of this book

Linux kernel is a complex, portable, modular and widely used piece of software, running on around 80% of servers and embedded systems in more than half of devices throughout the World. Device drivers play a critical role in how well a Linux system performs. As Linux has turned out to be one of the most popular operating systems used, the interest in developing proprietary device drivers is also increasing steadily. This book will initially help you understand the basics of drivers as well as prepare for the long journey through the Linux Kernel. This book then covers drivers development based on various Linux subsystems such as memory management, PWM, RTC, IIO, IRQ management, and so on. The book also offers a practical approach on direct memory access and network device drivers. By the end of this book, you will be comfortable with the concept of device driver development and will be in a position to write any device driver from scratch using the latest kernel version (v4.13 at the time of writing this book).
Table of Contents (23 chapters)
Free Chapter
1
Introduction to Kernel Development

The driver architecture

When the device for which you write the driver takes a seat on a physical bus called the bus controller, it must rely on the driver of that bus called the controller driver, responsible for sharing bus access between devices. The controller driver offers an abstraction layer between your device and the bus. Whenever you perform a transaction (read or write) on an I2C or USB bus, for example, the I2C/USB bus controller transparently takes care of that in the background. Every bus controller driver exports a set of functions to simplify the development of drivers for devices sitting on that bus. This works for every physical bus (I2C, SPI, USB, PCI, SDIO, and so on).

An I2C driver is represented in the kernel as an instance of struct i2c_driver. The I2C client (which represents the device itself) is represented by a struct i2c_client structure.

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