demo_driver.rar_DEMO_内核_内核移植

/************************************************************** demo.c linux driver example for up-tech270 platform It can be compiled for x86 PC author: wbn date: 2006-05-31 derive from zou jian-guo's driver exp. ***************************************************************/ //#define CONFIG_DEVFS_FS #ifdef MODULE //#include <linux/config.h> #include <linux/module.h> #ifdef CONFIG_DEVFS_FS #include <linux/devfs_fs_kernel.h> #endif #include <linux/init.h> #include <linux/kernel.h> /* printk() */ #include <linux/slab.h> /* kmalloc() */ #include <linux/fs.h> /* everything... */ #include <linux/errno.h> /* error codes */ #include <linux/types.h> /* size_t */ #include <linux/proc_fs.h> #include <linux/fcntl.h> /* O_ACCMODE */ #include <linux/poll.h> /* COPY_TO_USER */ #include <asm/system.h> /* cli(), *_flags */ #define DEVICE_NAME "UP-TECH DEMO" #define DEMORAW_MINOR 1 #define DEMO_Devfs_path "demo/0" static int demoMajor = 0; static int MAX_BUF_LEN=1024; static char drv_buf[1024]; static int WRI_LENGTH=0; /*************************************************************************************/ /*逆序排列缓冲区数据*/ static void do_write(void) { int i; int len = WRI_LENGTH; int mid = len>>1; char tmp; for(i = 0; i < mid; i++,len--){ tmp = drv_buf[len-1]; drv_buf[len-1] = drv_buf[i]; drv_buf[i] = tmp; } } /*************************************************************************************/ static ssize_t demo_write(struct file *file, const char __user *buffer, size_t count, loff_t * ppos) { if(count > MAX_BUF_LEN)count = MAX_BUF_LEN; copy_from_user(drv_buf , buffer, count); WRI_LENGTH = count; // printk("user write data to driver\n"); do_write(); return count; } /*************************************************************************************/ static ssize_t demo_read(struct file *filp, char __user *buffer, size_t count, loff_t *ppos) { if(count > MAX_BUF_LEN) count=MAX_BUF_LEN; copy_to_user(buffer, drv_buf,count); // printk("user read data from driver\n"); return count; } /*************************************************************************************/ static int demo_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg) { // printk("ioctl runing\n"); switch(cmd){ case 1:printk("runing command 1 \n");break; case 2:printk("runing command 2 \n");break; default: printk("error cmd number\n");break; } return 0; } /*************************************************************************************/ static int demo_open(struct inode *inode, struct file *filp) { // MOD_INC_USE_COUNT; printk("device open sucess!\n"); return 0; } /*************************************************************************************/ static int demo_release(struct inode *inode, struct file *filp) { // MOD_DEC_USE_COUNT; printk("device release\n"); return 0; } /*************************************************************************************/ static struct file_operations pxa270_fops = { owner: THIS_MODULE, write: demo_write, read: demo_read, ioctl: demo_ioctl, open: demo_open, release: demo_release, }; /*************************************************************************************/ static int __init demo_init(void) { int ret; ret = register_chrdev(0, DEVICE_NAME, &pxa270_fops); if (ret < 0) { printk(DEVICE_NAME " can't get major number\n"); return ret; } demoMajor=ret; #ifdef CONFIG_DEVFS_FS devfs_mk_cdev(MKDEV(demoMajor, DEMORAW_MINOR), S_IFCHR|S_IRUSR|S_IWUSR|S_IRGRP, DEMO_Devfs_path); #endif return 0; } /*************************************************************************************/ #ifdef MODULE void __exit demo_exit(void) { #ifdef CONFIG_DEVFS_FS devfs_remove(DEMO_Devfs_path); #endif unregister_chrdev(demoMajor, DEVICE_NAME); } module_exit(demo_exit); #endif /*************************************************************************************/ module_init(demo_init); MODULE_LICENSE("Dual BSD/GPL"); #endif // MODULE