82 lines
1.7 KiB
C
82 lines
1.7 KiB
C
/**
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* @file demo_misc.c
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* @author your name (you@domain.com)
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* @brief
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* @version 0.1
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* @date 2019-10-15
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*
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* @copyright Copyright (c) 2019
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*
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/miscdevice.h>
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static int demo_open(struct inode *inode, struct file* filp)
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{
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return 0;
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}
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static int demo_release(struct inode *inode, struct file* filp)
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{
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return 0;
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}
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static loff_t demo_llseek(struct file *filp, loff_t offset, int origin)
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{
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return filp->f_pos;
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}
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static ssize_t demo_read(struct file *filp, char __user *buffer, size_t count, loff_t *offset)
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{
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const char __user *p = buffer;
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return p-buffer;
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}
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static ssize_t demo_write(struct file *filp, const char __user *buffer, size_t count, loff_t *offset)
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{
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const char __user *p = buffer;
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return p-buffer;
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}
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static long demo_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
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{
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return 0;
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}
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static int demo_mmap(struct file* filp, struct vm_area_struct* vma)
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{
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return 0;
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}
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static struct file_operations demo_fops = {
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.owner = THIS_MODULE,
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.open = demo_open,
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.release = demo_release,
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.llseek = demo_llseek,
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.read = demo_read,
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.write = demo_write,
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.unlocked_ioctl = demo_ioctl,
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.mmap = demo_mmap
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};
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static struct miscdevice demo_dev = {
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.minor = MISC_DYNAMIC_MINOR, // Dynamically allocate minor.
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.name = "demo_misc",
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.fops = &demo_fops,
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};
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static int __init demo_init(void)
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{
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misc_register(&demo_dev);
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return 0;
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}
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static void __exit demo_exit(void)
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{
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misc_deregister(&demo_dev);
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}
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module_init(demo_init);
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module_exit(demo_exit); |