#include
#include
#include
#include
#include
#include
#include
#include
#define cmd_led_on 1
#define cmd_led_off 0
#define cmd_led_get_state 2
#define leds_num 4
#define s3c24xx_leds_phy_base 0x56000050
#define gpfcon_offset 0x0
#define gpfdat_offset 0x1
#define gpfup_offset 0x2
static int major = 0;
module_param(major, int, s_irugo|s_iwugo);
module_parm_desc(major,"s3c24xx leds major number");
struct s3c24xx_leds_dev ;
struct s3c24xx_leds_dev *devs =null;
static struct class *s3c24xx_leds_class; //建立led 類
static int s3c24xx_leds_open (struct inode *inode, struct file *filp)
static int s3c24xx_leds_close (struct inode *inode, struct file *filp)
static ssize_t s3c24xx_leds_read (struct file * filp, char __user *buf, size_t len, loff_t *loff)
return 0;
}static ssize_t s3c24xx_leds_write (struct file * filp, char __user *buf, size_t len, loff_t *loff)
kbuff = kbuff<<4;
//真正的led操作
// spin_lock(&pdev->spin);
down(&pdev->sem);
if ( pdev->led_state != kbuff ) else }}
}pdev->led_state = kbuff;
// spin_unlock(&pdev->spin);
up(&pdev->sem);
return 0;
}static int s3c24xx_leds_ioctl (struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
switch (cmd)
return 0;
}static struct file_operations s3c24xx_leds_ops = ;
static int __init s3c24xx_leds_init(void)
itmp = register_chrdev(dev_no, "leds", &s3c24xx_leds_ops);
if(itmp < 0)
if( itmp > 0 )
major = itmp;
printk("major = %d\n", major);
s3c24xx_leds_class = class_create(this_module, "leds");//在驅動初始化的**裡呼叫class_create為該裝置建立乙個class，
//再為每個裝置呼叫 class_device_create建立對應的裝置
if(is_err(s3c24xx_leds_class))
#if linux_version_code < kernel_version(2,6,18)
class_device_create(s3c24xx_leds_class,mkdev(major, 0), null, "leds");
#else
device_create(s3c24xx_leds_class,null,mkdev(major, 0), null, "leds");//在/dev目錄下建立相應的裝置節點
#endif
//位址對映
pmem = ioremap(s3c24xx_leds_phy_base, 12);
if (!pmem)
devs->pbase = pmem;
// spin_lock_init(&devs->lock);
//semaphore initialize.
// sem_init(&devs->sem, 1);
init_mutex(&devs->sem);
return 0;
out2:
unregister_chrdev(dev_no, "leds");
out1:
kfree(devs);
out:
return ret;
}static void __exit s3c24xx_leds_exit(void)
module_init(s3c24xx_leds_init);
module_exit(s3c24xx_leds_exit);
module_license("gpl");
module_author("stephenyee([email protected])");
應用程式：
#include
#include
#include
#include
#include
#include
#include
#include
#define leds_name "/dev/leds"
#define cmd_led_on 1
#define cmd_led_off 0
#define cmd_led_get_state 2
#define leds_num 4
int main (int argc, char **argv)
//讀取當前led狀態
ret = read(fd, &buf, 1);
if (ret < 0)
for (i = 0; i< leds_num; i++) {
printf( "led%d state is:%s\n", i+1, buf & (1for (i = 0; i< leds_num; i++) {
printf( "1: led%d state is:%s\n", i+1, buf & (1ioctl (fd, cmd_led_on, 3);
// get state
ret = ioctl (fd, cmd_led_get_state, &leds);
leds &= 0x0f;
printf("ret = %d, leds =%d\n",ret, leds);
for (i = 0; i< leds_num; i++) {
printf( " 3: led%d state is:%s\n", i+1, leds & (1<
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