Manual Zone

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/major.h>
#include <linux/capability.h>
#include <asm/uaccess.h>
#include <linux/miscdevice.h>


static ssize_t sample_char_read(struct file * file, char __user * buf,
 size_t count, loff_t *ppos)
{
 printk("sample_char_read size(%ld) ", count);
 return 0;
}

static ssize_t sample_char_write(struct file *filp, const char *buf,
 size_t size, loff_t *offp)
{
 printk("sample_char_write size(%ld) ", size);
 return size;

}

int sample_char_open(struct inode *inode, struct file *filp)
{
 printk("sample_char_open ");
 return 0;
}

int sample_char_release(struct inode *inode, struct file *filp)
{

 printk("sample_char_release ");
 return 0;
}

static struct file_operations sample_char_fops = {
       read: sample_char_read,
       write: sample_char_write,
       open: sample_char_open,
       release: sample_char_release,
};

static struct miscdevice misc_dev = {
 .minor = MISC_DYNAMIC_MINOR,
 .name = "sample_misc_dev",
 .fops = &sample_char_fops,
 .mode = S_IRWXUGO,
};

int init_module(void)
{
 int ret = 0;
 printk(" Loading the sample misc char device driver ");
 ret = misc_register(&misc_dev);
 if (ret)
 printk("Unable to register misc dev ");
 return ret;
}

void cleanup_module(void)
{
 printk(" Unloading the sample char device driver ");
 misc_deregister(&misc_dev);
}