Linux下简易蜂鸣器驱动代码及测试实例

驱动代码：

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/err.h>


#include <linux/miscdevice.h>


#include <mach/gpio.h>
#include <mach/regs-gpio.h>
#include <plat/gpio-cfg.h>


#define DEVICE_NAME                "beep3"

#define BEEP_MAGIC 'k'
#define BEEP_START_CMD _IO (BEEP_MAGIC, 1)
#define BEEP_STOP_CMD _IO (BEEP_MAGIC, 2)


static void beep3_stop(void) {
    printk("in the beep3_stop!!\n");
    s3c_gpio_cfgpin(S5PV210_GPD0(0), S3C_GPIO_OUTPUT);
    gpio_set_value(S5PV210_GPD0(0), 0);

}

static void beep3_start(void) {
    printk("in the beep3_start!!\n");
    s3c_gpio_cfgpin(S5PV210_GPD0(0), S3C_GPIO_OUTPUT);
    gpio_set_value(S5PV210_GPD0(0), 1);

}


static long beep3_ioctl(struct file *filep, unsigned int cmd,
        unsigned long arg)
{
    printk("in the beep3_ioctl!!\n");
    switch ( cmd ) {
        case BEEP_START_CMD: {
            printk("in the start_cmd!!\n");
            beep3_start();     break;
        }
        case BEEP_STOP_CMD: {
            printk("in the stop_cmd!!\n");
            beep3_stop();     break;
        }
        default: {
            break;
        }
    }

    return 0;
}


static struct file_operations beep3_fops = {
    .owner            = THIS_MODULE,
    .unlocked_ioctl    = beep3_ioctl,
};

static struct miscdevice beep3_misc_dev = {
    .minor = MISC_DYNAMIC_MINOR,
    .name = DEVICE_NAME,
    .fops = &beep3_fops,
};

static int __init beep3_dev_init(void) {
    int ret;

    ret = gpio_request(S5PV210_GPD0(0), DEVICE_NAME);
    if (ret) {
        printk("request GPIO %d  failed\n",S5PV210_GPD0(0));
        return ret;
    }
    s3c_gpio_cfgpin(S5PV210_GPD0(0), S3C_GPIO_OUTPUT);
    gpio_set_value(S5PV210_GPD0(0), 0);
    

    ret = misc_register(&beep3_misc_dev);

    printk(DEVICE_NAME "\tinitialized\n");

    return ret;
}

static void __exit beep3_dev_exit(void) {
    beep3_stop();

    misc_deregister(&beep3_misc_dev);
}

module_init(beep3_dev_init);
module_exit(beep3_dev_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("mhb@SEU");
MODULE_DESCRIPTION("S5PV210 beep Driver");

测试实例：

#include <stdio.h>
#include <unistd.h> 
#include <stdlib.h> 
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h> 
#define BEEP_MAGIC 'k'
#define BEEP_START_CMD _IO (BEEP_MAGIC, 1)
#define BEEP_STOP_CMD _IO (BEEP_MAGIC, 2)

int main(int argc ,char* argv[])
{
   int m_fd=0;// 
   m_fd = open("/dev/beep3", O_RDONLY); 
 

   ioctl(m_fd, BEEP_STOP_CMD);
   while(1)
       {
       printf("enter any key to start !!\n");
       getchar();
       ioctl(m_fd, BEEP_START_CMD);
       printf("start success!!\n");
       printf("enter any key to stop !!\n");
       getchar();
       ioctl(m_fd, BEEP_STOP_CMD);
       }
   close(m_fd);
   return 0; 
}