Question

I’ve started to learn Linux driver programs, but I’m finding it a little difficult.

I’ve been studying the i2c driver, and I got quite confused regarding the entry-point of the driver program. Does the driver program start at the MOUDULE_INIT() macro?

And I’d also like to know how I can know the process of how the driver program runs. I got the book, Linux Device Driver, but I’m still quite confused. Could you help me? Thanks a lot.

I’ll take the i2c driver as an example. There are just so many functions in it, I just wanna know how I can get coordinating relation of the functions in the i2c drivers?

Answer 1

"Linux Device Driver" is a good book but it’s old!

Basic example:

#include <linux/module.h>
#include <linux/version.h>
#include <linux/kernel.h>

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Name and e-mail");
MODULE_DESCRIPTION("my_first_driver"); 

static int __init insert_mod(void)
{
    printk(KERN_INFO "Module constructor");
    return 0;
}

static void __exit remove_mod(void)
{
    printk(KERN_INFO "Module destructor");
}

module_init(insert_mod);
module_exit(remove_mod);

An up-to-date tutorial, really well written, is "Linux Device Drivers Series"