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
Introduction to Kernel Development

Invoking user space applications from the kernel

User-space applications are, most of the time, called from within the user space by other applications. Without going deep into the details, let's see an example:

#include <linux/init.h> 
#include <linux/module.h> 
#include <linux/workqueue.h>    /* for work queue */ 
#include <linux/kmod.h> 
static struct delayed_work initiate_shutdown_work; 
static void delayed_shutdown( void ) 
   char *cmd = "/sbin/shutdown"; 
   char *argv[] = { 
   char *envp[] = { 
   call_usermodehelper(cmd, argv, envp, 0); 
static int __init my_shutdown_init( void )