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#include <linux/module.h> /*EXPORT_SYMBOL_GPL ())*/
#include<linux/moduleparam.h>/*module_param(variable,type,perm); */
#include <linux/init.h>/*module_init(init_function); module_exit(cleanup_function); */
#include <linux/kdev_t.h> /*dev_t*/
#include <linux/fs.h>/* everything... */
#include <linux/cdev.h> /*struct cdev *cdev_alloc(void); */
#include <linux/device.h> /*struct class*/
#include <asm/arch/regs-gpio.h> /*S3C2410_GPB5*/
#include <asm/hardware.h> /* s3c2410_gpio_cfgpin(unsigned int pin, unsigned int function)*/
#include<linux/ioctl.h>
#include <asm/uaccess.h> /* copy_*_user access_ok*/
#include "devleds.h"
static int leds_major, leds_minor = 0;
static struct cdev cdev; //字符设备结构
static struct class *leds_class;
dev_t dev;//设备号
static unsigned long leds_table[] = { //led的引脚定义表
S3C2410_GPB5,
S3C2410_GPB6,
S3C2410_GPB7,
S3C2410_GPB8
};
static unsigned int leds_cfg_table[] = { //led引脚功能定义表
S3C2410_GPB5_OUTP,
S3C2410_GPB6_OUTP,
S3C2410_GPB7_OUTP,
S3C2410_GPB8_OUTP,
};
static int leds_open(struct inode *inode, struct file *filp)
{
int i;
// for(i = 0; i < 4; i++){ //引脚初始化，由于内核在已经初始化过一次，本处不必在初始化，否则得不到结果
//s3c2410_gpio_cfgpin(leds_table[i], leds_cfg_table[i]);//arch/arm/plat-s3c24xx/gpio.c:void s3c2410_gpio_cfgpin(unsigned int pin, unsigned int function)
}
return 0;
}
static int leds_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
{
int err = 0, i;
if (_IOC_TYPE(cmd) != LEDS_IOC_MAGIC)
return -ENOTTY;
if (_IOC_NR(cmd) > LEDS_IOC_MAXNR)
return -ENOTTY;
/*
* the direction is a bitmask, and VERIFY_WRITE catches R/W
* transfers. `Type' is user-oriented, while
* access_ok is kernel-oriented, so the concept of "read" and
* "write" is reversed
*/
if (_IOC_DIR(cmd) & _IOC_READ)
err = !access_ok(VERIFY_WRITE, (void __user *)arg, _IOC_SIZE(cmd));
else if (_IOC_DIR(cmd) & _IOC_WRITE)
err = !access_ok(VERIFY_READ, (void __user *)arg, _IOC_SIZE(cmd));
if (err)
return -EFAULT;
printk(KERN_WARNING"Here\n");
switch(cmd)
{
case LEDS_IOCRESET:
for(i = 0; i < 4; i++){
s3c2410_gpio_setpin(leds_table[i], 1);
}
printk(KERN_WARNING"Here\n");
return 0;
case LEDS_IOCSON:
s3c2410_gpio_setpin(leds_table[arg], 0);
return 0;
case LEDS_IOCSOFF:
s3c2410_gpio_setpin(leds_table[arg], 1);
return 0;
default:
return -EINVAL;
}
return 0;
}
static struct file_operations leds_fops = {
.owner = THIS_MODULE,
.open = leds_open,
.ioctl = leds_ioctl
};
static int __init leds_init(void) //模块初始化
{
int result;
PDEBUG("Debug Opend!\n"); 我写来测试调试是否打开了的
if (leds_major) {
dev = MKDEV(leds_major, leds_minor);
result = register_chrdev_region(dev, 1, DEV_NAME);//此处为静态分配主设备号
} else {
result = alloc_chrdev_region(&dev, leds_minor, 1, DEV_NAME);//动态分配主设备号，此设备号为0
leds_major = MAJOR(dev);//获取主设备号的宏
}
if (result < 0) {
printk(KERN_WARNING "Leds: can't get major %d\n", leds_major);
return result;
}else {
printk(KERN_WARNING"Registered ok \nLeds_major = %d\n", leds_major);
}
cdev_init(&cdev, &leds_fops) ;//初始化最先定义的字符设备结构
cdev.owner = THIS_MODULE;
cdev.ops = &leds_fops;
result = cdev_add(&cdev, dev, 1);//通知内核有该结构注册，注意考虑失败
if(result < 0){
printk(KERN_WARNING"cdev_add failed!\n");
return result;
}
leds_class = class_create(THIS_MODULE, DEV_NAME);//creat自己的设备节点
if(IS_ERR(leds_class))
{
printk(KERN_ALERT"Err:faile in leds_class!\n");
return -1;
}
/*创建设备节点，名字为DEVICE_NAME ，主设备号用上面动态生成的dev*/
class_device_create(leds_class, NULL, dev, NULL, DEV_NAME);
printk(KERN_WARNING"Leds Module Initialed!\n");
return 0;
}
static void __exit leds_exit(void)
{
int devno = MKDEV(leds_major, leds_minor );
unregister_chrdev_region(devno, 1);//销毁设备号
cdev_del(&cdev);//销毁字符设备结构
class_device_destroy(leds_class, devno); //销毁注册的类
class_destroy(leds_class);
printk(KERN_WARNING"Leds Module exit!\n");
}
module_init(leds_init);
module_exit(leds_exit);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("CHARACTER DEVICE DRVER");
MODULE_AUTHOR();
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