main.c~

嵌入式LINUX I/O口驱动,YC2410-SBC T2 平台

#include<linux/init.h>
#include<linux/module.h>
MODULE_LICENSE("Dual BSD/GPL");
#include<linux/config.h>
#include<linux/kernel.h>
#include<asm/arch-s3c2410/regs-gpio.h>
#include<asm/arch/hardware.h>
#include<linux/fs.h>
#include<linux/delay.h>
#include<asm/uaccess.h>

#undef DEBUG
//#define DEBUG
#ifdef DEBUG
#define DPRINTK(X...) printk("s3c2410-led:"##x)
#else 
#define DPRINK(x...)
#endif

#define LEDGreen S3C2410_GPG11
# define DEVICE_NAME "s3c2410-led"
#define Led_MINOR 1
static int Led_Major=0;

extern void s3c2410_gpio_cfgpin(unsigned int pin,unsigned int function);
extern void s3c2410_gpio_setpin(unsigned int pin,unsigned int to);
extern unsigned int s3c2410_gpio_getpin(unsigned int pin);
extern void s3c2410_gpio_pullup(unsigned int pin,unsigned int to);
static int led_read(struct file * file, char * buffer, size_t count, loff_t *ppos)
{   
        unsigned int value;   
        value=s3c2410_gpio_getpin(S3C2410_GPG3);
        //s3c2410_gpio_pullup(S3C2410_GPE8,0);
        //s3c2410_gpio_cfgpin(S3C2410_GPE8,S3C2410_GPE8_SDDAT1);
        printk(KERN_INFO "read\n");
        if(value!=0) return 1;
        else return 0;
}
static int led_write(struct file * file, const char * buffer, size_t count, loff_t *ppos)
{   
         s3c2410_gpio_cfgpin(S3C2410_GPF4, S3C2410_GPF4_OUTP);
         s3c2410_gpio_setpin(S3C2410_GPF4,0);
         printk(KERN_INFO "write\n");
         return 0;
}
static struct file_operations led_fops = {
        .owner     =       THIS_MODULE,
        .read       =       led_read,
        .write      =       led_write,
};
static int Led_open(struct inode *inode,struct file *filp)
{
        //MOD_INC_USE_COUNT;
	DPRINTK("open\n");
	return 0;
}

static int Led_release(struct inode *inode,struct file *filp)
{
	//MOD_DEC_USE_COUNT;
	DPRINTK("releaes\n");
	return 0;
}


#ifdef  CONFIG_DEVICES_FS
static devfs_handle_t devfs_Led_dir;
static devfs_handle_t devfs_Led_raw;
#endif

static int __init Led_init(void)
{
   int ret;
   ret=register_chrdev(0,DEVICE_NAME,&led_fops);
   if(ret<0)
   {
	   printk(DEVICE_NAME"can't get major number\n");
	   return ret;
   }
   Led_Major=ret;
   
//#ifdef  CONFIG_DEVFS_FS
  //    devfs_Led_dir=devfs_mk_dir(NULL,"led",NULL);
   //   devfs_Led_raw=devfs_register(devfs_Led_dir,"0",DEVFS_FL_DEFAULT,Led_Major,
		                            //Led_MINOR,S_IFCHR|S_IRUSR|S_IWUSR,&led_fops,NULL);

//#endif
   //-------------------3--
    printk(DEVICE_NAME"initialized\n");
	return 0;
}

static void __exit  Led_exit(void)
{
//#ifdef  CONFIG_DEVFS_FS
	//        devfs_unregister(devfs_Led_raw);
	//	devfs_unregister(devfs_Led_dir);
//#endif
		unregister_chrdev(Led_Major,DEVICE_NAME);
}

module_init(Led_init);
module_exit(Led_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("threewater<[e-mail]>");
MODULE_DESCRIPTION("gpio(led) driver for s3c2410");