基于linux2.6.30.4的s3c2440的led字符驱动

1 driver

#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 "led0"

static unsigned long led_table [] = {

S3C2410_GPB(5),

S3C2410_GPB(6),

S3C2410_GPB(7),

S3C2410_GPB(8),

};

/*将I/O口设置为输出功能*/

static unsigned int led_cfg_table [] = {

S3C2410_GPIO_OUTPUT,

S3C2410_GPIO_OUTPUT,

S3C2410_GPIO_OUTPUT,

S3C2410_GPIO_OUTPUT,

};

/*对LED文件操作*/

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;

}

}

/*miscdevice*/

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,

};

/*设备的初始化函数*/

static int __init dev_init(void)

{

int ret;

int i;

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

s3c2410_gpio_cfgpin(led_table[i], led_cfg_table[i]);

s3c2410_gpio_setpin(led_table[i], 1);//off

}

ret = misc_register(&misc);

printk (DEVICE_NAME"\tinitialized\n");

return ret;

}

/*设备注销程序*/

static void __exit dev_exit(void)

{

misc_deregister(&misc);

printk(DEVICE_NAME"\tclose!!\n");

}

module_init(dev_init);

module_exit(dev_exit);

MODULE_LICENSE("GPL");

MODULE_AUTHOR("FriendlyARM Inc.");

2 test

#include <string.h>

#include <stdlib.h>

#include <fcntl.h> // open() close()

#include <unistd.h> // read() write()

#define LED_ON 1

#define LED_OFF 0

int main(void)

{

int fd,i;

fd = open("/dev/led0", 0);

if (fd < 0)

{

printf("open device /lib/modulew/2.6.32.2/myled-ioctl error!\n");

}

else

{

while(1)

{

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

{

printf("led%d is on!\n",i);

ioctl(fd,LED_ON,i);

sleep(1);//等待1秒再做下一步操作

printf("led%d is off!\n",i);

ioctl(fd,LED_OFF,i);

sleep(1);

}

if(i==4)

i=0;

}

close(fd);

}

return 0;

}