leddrv.c

Linux设备驱动程序 硬件平台：H9200评估板（基于AT91RM9200构建） 软件平台：Linux-2.4.19-rmk7 驱动设备：LED 作者：flyerwing 编写驱动程序

/***************************************************************
* Institue of Automation,Chinese Academy of Sciences
* File Name: leddrv.c
* Description: Light leds on h9200 board
* Author: Wei An
***************************************************************/

#ifdef MODULE
#include <linux/module.h>
//#include <linux/version.h>
#else
//#define MOD_INC_USE_COUNT
//#define MOD_DEC_USE_COUNT
#endif

#define __KERNEL__
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <linux/fcntl.h>
#include <asm/arch/AT91RM9200_SYS.h>

#define IOPMOD               (*(volatile unsigned *)0x03FF5000) //IO port data register
#define GET_DATA 0x4800
static int led_write(struct file *,const char *,int,loff_t *);
static int led_ioctl(struct inode *,struct file *,int,unsigned long);
static void Delay(int);
static unsigned int major =0;

static struct file_operations led_fops=
{
      write	:(void(*))led_write,
      ioctl	:(void(*))led_ioctl,
};

char led_name[]="leddrv";            

static int __init leddrv_init_module(void)
{
      int retv;
      retv=register_chrdev(major,led_name,&led_fops);
      if(retv<0)
      {
         printk("<1>Register Fail!\n");
         return retv;
      }
     if(major==0)
        major=retv;
     
     printk("<1>Led device OK!\n");
     return 0;

}

static void __exit leddrv_cleanup(void)
{
      int retv;
      retv=unregister_chrdev(major,led_name);
      if(retv<0)
      {
        printk("<1>UnRegister Fail!\n");
        return;
      }
      printk("<1>LEDDRV:GOOD-bye!\n");

}

static int led_write(struct file *led_file, const char *buf,int len,loff_t *loff)
{
       unsigned int iopdata;
       AT91PS_SYS sys = (AT91PS_SYS) AT91C_VA_BASE_SYS;  
       sys->PIOC_PER=(unsigned int)(1<<14)|(unsigned int)(1<<15);
       sys->PIOC_OER=(unsigned int)(1<<14)|(unsigned int)(1<<15);
     
       if(copy_from_user((char*)&iopdata,buf,len))
         return -EFAULT;
       sys->PIOC_SODR=iopdata; 
       Delay(100);
       AT91_SYS->PIOC_CODR=iopdata; 
       return len;

}

static int led_ioctl(struct inode * s_node,struct file * s_file,int cmd,unsigned long arg)
{      
       int retv;
       switch(cmd)
       {
        case GET_DATA:
             retv=copy_to_user((void*)arg,(char*)&IOPMOD,sizeof(int));
             if(retv<0)
                return -1;
             printk("<1>get timer0 flag ok\n");
             break;
       default:
             break;

       }
      return 0;
}
static void Delay(int x)
{
	int i,j,k;
	for(i=0;i<x;i++)
		for(j=0;j<0xff;j++)
			for(k=0;k<0xff;k++);
}

module_init(leddrv_init_module);
module_exit(leddrv_cleanup);

//MODULE_LICENSE("GPL");
//MODULE_AUTHOR("Wei An");
//MODULE_DESCRIPTION("Led driver for H9200 board");
//MODULE_PARM(debug, "i");
/*end of leddrv.c*/