基于linux的mini2440 led驱动及应用程序

驱动程序：

#include <linux/miscdevice.h>

#include <linux/delay.h>

#include <asm/irq.h>

#include <mach/regs-gpio.h>

#include <mach/hardware.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/mm.h>

#include <linux/fs.h>

#include <linux/types.h>

#include <linux/delay.h>

#include <linux/moduleparam.h>

#include <linux/slab.h>

#include <linux/errno.h>

#include <linux/ioctl.h>

#include <linux/cdev.h>

#include <linux/string.h>

#include <linux/list.h>

#include <linux/pci.h>

#include <linux/gpio.h>

#include <asm/uaccess.h>

#include <asm/atomic.h>

#include <asm/unistd.h>

#define DEVICE_NAME "leds"

// addresses of 4 pins connected with leds are written in the "led_table"

static unsigned long led_table [] = {

S3C2410_GPB(5),

S3C2410_GPB(6),

S3C2410_GPB(7),

S3C2410_GPB(8),

};

//led configuration table

static unsigned int led_cfg_table [] = {

S3C2410_GPIO_OUTPUT,

S3C2410_GPIO_OUTPUT,

S3C2410_GPIO_OUTPUT,

S3C2410_GPIO_OUTPUT,

};

//**************************************************************************

//turn on or off appointed led

static int sbc2440_leds_ioctl(

struct inode *inode,

struct file *file,

unsigned int cmd,

unsigned long arg)

{

switch(cmd) {

case 0:

case 1:

if (arg > 4) {

return -EINVAL;

}

s3c2410_gpio_setpin(led_table[arg], !cmd);

return 0;

default:

return -EINVAL;

}

}

//**************************************************************************

static struct file_operations dev_fops = {

.owner = THIS_MODULE,

.ioctl = sbc2440_leds_ioctl,

};

static struct miscdevice misc = {

.minor = MISC_DYNAMIC_MINOR,

.name = DEVICE_NAME,

.fops = &dev_fops,

};

//**************************************************************************

static int __init dev_init(void) //module entry

{

int ret;

int i;

for (i = 0; i < 4; i++) {

s3c2410_gpio_cfgpin(led_table[i], led_cfg_table[i]);//configure 4 pins to output pins

s3c2410_gpio_setpin(led_table[i], 0);//initialize leds' state

}

ret = misc_register(&misc); //register device

printk (DEVICE_NAME"\tinitialized\n");

return ret;

}

//**************************************************************************

static void __exit dev_exit(void) //module exit

{

misc_deregister(&misc); //deregister device

}

//**************************************************************************

module_init(dev_init); //appoint module entry

module_exit(dev_exit); //appoint module exit

MODULE_LICENSE("GPL");

MODULE_AUTHOR("FriendlyARM Inc.");

//**************************************************************************

//**************************************************************************

应用程序：

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

#include <sys/ioctl.h>

int main(int argc, char **argv)

{

int on;

int led_no;

int fd;

/* 检查 led控制的两个参数，如果没有参数输入则退出。*/

if (argc != 3 || sscanf(argv[1], "%d", &led_no) != 1 || sscanf(argv[2],"%d", &on) != 1 ||

on < 0 || on > 1 || led_no < 0 || led_no > 3) {

fprintf(stderr, "Usage: leds led_no 0|1\n");

exit(1);

}

/*打开/dev/leds设备文件*/

fd = open("/dev/leds", 0);

if (fd < 0) {

perror("open device leds");

exit(1);

}

/*通过系统调用 ioctl和输入的参数控制 led*/

ioctl(fd, on, led_no);

/*关闭设备句柄*/

close(fd);

return 0;

}