#include <linux/module.h>#include <linux/kernel.h>#include <linux/init.h>#include <linux/errno.h>#include <linux/slab.h>#include <linux/input.h>#include <linux/serio.h>#include <linux/delay.h>#include <linux/clk.h>#include <linux/miscdevice.h>#include <linux/gpio.h>#include <asm/io.h>#include <asm/irq.h>#include <asm/uaccess.h>#include <mach/regs-clock.h>#include <plat/regs-timer.h>#include <mach/regs-gpio.h>#include <linux/cdev.h>MODULE_LICENSE("GPL");MODULE_AUTHOR("liuchang");#define beep_name "beep"#define DEV_NUM 5struct class * class;struct device * devices[DEV_NUM];#define MAGIC 'b'#define START_BEEP _IO(MAGIC,0)#define STOP_BEEP _IO(MAGIC,1)static struct cdev beep_dev;static ssize_t beep_read(struct file * fp,char __user * buffer,size_t count,loff_t * l){return 0;}static ssize_t beep_write(struct file * fp,const char __user * buffer,size_t count,loff_t * l){return 0;}static int beep_open(struct inode * ip,struct file *fp){return 0;}static int beep_release(struct inode * ip,struct file *fp){return 0;}static void start_beep(){s3c2410_gpio_cfgpin(S3C2410_GPB(0),S3C2410_GPIO_OUTPUT);s3c2410_gpio_setpin(S3C2410_GPB(0),1);}static void stop_beep(){s3c2410_gpio_cfgpin(S3C2410_GPB(0),S3C2410_GPIO_OUTPUT);s3c2410_gpio_setpin(S3C2410_GPB(0),0);}static int beep_ioctl(struct inode * ip,struct file *fp,unsigned int cmd,unsigned long count){switch(cmd){case START_BEEP :{start_beep();break;}case STOP_BEEP :{stop_beep();break;}default:{return 0;}}return 0;}static struct file_operations fo = {.owner = THIS_MODULE,.read = beep_read,.write = beep_write,.ioctl = beep_ioctl,.open = beep_open,.release = beep_release,};static int beep_major = 0;module_param(beep_major,int,0444);static int __init beep_init(){int i = 0;char dev_name[10];//alloc dev_tdev_t dev = MKDEV(beep_major,0);if(beep_major){register_chrdev_region(dev,DEV_NUM,beep_name);} else {alloc_chrdev_region(&dev,0,DEV_NUM,beep_name);beep_major = MAJOR(dev);}printk(KERN_EMERG"major is %d\n",beep_major);//init cdevcdev_init(&beep_dev,&fo);beep_dev.owner = THIS_MODULE;cdev_add(&beep_dev,dev,DEV_NUM);// class is like a container of devices--------------// class相当于一个容器，可以存放多个类型相同的deviceclass = class_create( THIS_MODULE,"beep_class");for( i=0;i<DEV_NUM;i++ ){dev = MKDEV( beep_major,i );sprintf( dev_name,"beep%d",i);devices[i] = device_create( class,NULL,dev,NULL,dev_name);}//then /sys/class/beep_class/beepN directories createdreturn 0;}static void __exit beep_exit(){int i = 0;dev_t dev = 0;cdev_del(&beep_dev);for( i=0;i<DEV_NUM;i++){dev = MKDEV( beep_major,DEV_NUM);device_destroy( class,dev);}class_destroy( class);unregister_chrdev_region(dev,2);}module_init(beep_init);module_exit(beep_exit);
