Single Linux Device Driver code for multiple Linux versions using LINUX_VERSION

The arguments of the kernel functions changes with new releases.

For example, Kernel versions > 3.10 use the below function to create a proc entry

  proc_file_entry = proc_create("proc_file_name", 0, NULL, &proc_file_fops);

For kernel versions < 3.10, this API was

  proc_file_entry = create_proc_entry("proc_file_name", 0, NULL);

If you want to have a Linux Device Driver which supports multiple Linux Versions, use the macro LINUX_VERSION_CODE

This macro expands to the binary representation of the kernel version
For example for Linux version 2.6.10, the value is 132618(0x02060a)

There is another macro KERNEL_VERSION(major, minor, release). This builds up the version number from the individual numbers. For example KERNEL_VERSION(2,6,10) will return 132618

Sample Code:

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <asm/current.h>
	#include <linux/sched.h>
	#include <generated/utsrelease.h>
	#include <linux/version.h>
	MODULE_LICENSE("GPL");
	static int __init kernel_version_init(void)
	{
	//Now depends on our Kernel version we could log a diffrent comment in the Kernel log
	#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 10)
	printk(KERN_INFO "KERNELVERSION: Hello OLD Kernel %s\n", UTS_RELEASE);
	#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0)
	printk(KERN_INFO "KERNELVERSION: Hello NEW Kernel %s\n", UTS_RELEASE);
	#else
	printk(KERN_INFO "KERNELVERSION: Hello Moderate Kernel %s\n", UTS_RELEASE);
	#endif
	return 0;
	}
	static void __exit kernel_version_exit(void)
	{
	printk(KERN_INFO "KERNELVERSION: GoodBye.\n");
	}
	module_init(kernel_version_init);
	module_exit(kernel_version_exit);

view raw kernelversion.c hosted with ❤ by GitHub

Output: