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

Platform drivers

Before going further, please pay attention to the following warning: not all platform devices are handled by platform drivers (or should I say pseudo platform drivers). Platform drivers are dedicated to devices not based on conventional buses. I2C devices or SPI devices are platform devices, but respectively rely on I2C or SPI buses, not on the platform bus. Everything needs to be done manually with the platform driver. The platform driver must implement a probe function, called by the kernel when the module is inserted or when a device claims it. When developing platform drivers, the main structure you have to fill is struct platform_driver, and registering your driver with the platform bus core with dedicated functions shown as follows:

static struct platform_driver mypdrv = { 
    .probe    = my_pdrv_probe, 
    .remove   = my_pdrv_remove, 
    .driver   =...