gpio_driv.c

基于linux和s3c2440的gpio驱动程序

#include <linux/config.h>
#include <linux/init.h>
                                                                              
//#include <kernel.h>  
#include <asm/hardware.h>
#include <asm/leds.h>
#include <asm/system.h>
#include <asm/arch/smdk.h>

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/miscdevice.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>

#include <linux/version.h>
#include <asm/arch/smdk.h>
#include <asm/arch/S3C2440.h>

#define LED0            (1 << 0)
#define LED1            (1 << 1)
#define LED2            (1 << 2)
#define LED3            (1 << 3)

#define __NO_VERSION__
                                                                               
#ifndef KERNEL_VERSION
#define KERNEL_VERSION(a,b,c) ((a)*65536+(b)*256+(c))
#endif
#define DEVICE_NAME "gpio_driv"
#define IOPORT_MAJOR 100 //定义主设备号，和前面的mknod/dev/gpiotestc 220 0匹配

#define GPIO_A_CON  0x56000000
#define GPIO_A_DAT  0x56000004
#define GPIO_B_CON  0x56000010
#define GPIO_B_DAT  0x56000014
#define GPIO_B_PUP  0x56000018
#define GPIO_C_CON  0x56000020
#define GPIO_C_DAT  0x56000024
#define GPIO_C_PUP  0x56000028
#define GPIO_D_CON  0x56000030
#define GPIO_D_DAT  0x56000034
#define GPIO_D_PUP  0x56000038
#define GPIO_E_CON  0x56000040
#define GPIO_E_DAT  0x56000044
#define GPIO_E_PUP  0x56000048
#define GPIO_F_CON  0x56000050
#define GPIO_F_DAT  0x56000054
#define GPIO_F_PUP  0x56000058
#define GPIO_G_CON  0x56000060
#define GPIO_G_DAT  0x56000064
#define GPIO_G_PUP  0x56000068
#define GPIO_H_CON  0x56000070
#define GPIO_H_DAT  0x56000074
#define GPIO_H_PUP  0x56000078
#define GPIO_J_CON  0x56000080
#define GPIO_J_DAT  0x56000084
#define GPIO_J_PUP  0x56000088


static int gpio_open(struct inode*, struct file *);
static int gpio_release(struct inode*, struct file *);
static int gpio_ioctl(struct inode *, struct file *, unsigned int intcommand, unsigned long arg);
static int gpio_read(struct file *file,
                            char *buffer,       /* The buffer to fill with data
*/                          size_t length,      /* The length of the buffer */
                            loff_t * offset);    /* Our offset in the file */
static int gpio_write(struct file *inode, const char *gdata, size_t length, loff_t *off_what);

                                                                                
char kernel_version [] = UTS_RELEASE;

static struct file_operations gpio_ctl_fops=
 { ioctl: gpio_ioctl,
    read: gpio_read,
    write:gpio_write,
    open: gpio_open,
    release: gpio_release,
};

                                                                       
static int gpio_open(struct inode *inode, struct file *file)
{
        MOD_INC_USE_COUNT;
   printk ("device_open(%p,%p)\n", inode, file);
                                                                                
        /*
         * Get major / minor numbers when needed
         */
        printk ("Device: %d.%d\n", inode->i_rdev >> 8, inode->i_rdev & 0xFF);
                                                                                
        return 0;
}
                                                                                
static int gpio_release(struct inode *inode, struct file *file)
{
        MOD_DEC_USE_COUNT;
        return 0;
}

                                                                                
static int gpio_ioctl(struct inode*inode,struct file *flip,unsigned intcommand,unsigned long arg)
{
return 0;
}


static int gpio_read(struct file *file,
                            char *buffer,     /*buffer[0-3]=addr buffer[4-7]= bit */
                            size_t length,      
                            loff_t * offset)   
{
      unsigned long templong,tempcon,tmpold;
      unsigned char i;
      int bit,GPIOAddr,GPIOData,temp_gdata[8]; 
       for(i=0;i<8;i++)
        temp_gdata[i]=(int)buffer[i];
      GPIOAddr=temp_gdata[0]+temp_gdata[1]*256+temp_gdata[2]*256*256+temp_gdata[3]*256*256*256;
      GPIOData=temp_gdata[4]+temp_gdata[5]*256+temp_gdata[6]*256*256+temp_gdata[7]*256*256*256;
//      printk("\n GPIOAddr=%x  GPIOData=%x", GPIOAddr,GPIOData);    
      tempcon=*((volatile unsigned long *)io_p2v(GPIOAddr ));
       
      tmpold=tempcon;
      
      if (length&0x8)
      {
      printk("CON is %x,DAT is %x, PULL is %x\n",
      *((volatile unsigned long *)io_p2v( GPIOAddr  )),
      *((volatile unsigned long *)io_p2v( GPIOAddr+4)),
      *((volatile unsigned long *)io_p2v( GPIOAddr+8)));
      return 0;
      }

     if (length&0x2)  //about set pullup, 1 set, 0 disable  
     {
           switch(length&0x1)
           {
      		case 1:  
        	templong= *((volatile unsigned long *)io_p2v( GPIOAddr+8)); 
        	*((volatile unsigned long *)io_p2v(GPIOAddr+8 ))=templong|(1<<GPIOData); //GP DAT =1
		break;
      		
      		case 0: 
        	templong= *((volatile unsigned long *)io_p2v(GPIOAddr+8 )); 
        	*((volatile unsigned long *)io_p2v(GPIOAddr+8 ))=templong&(~(1<<GPIOData)); //GP DAT = 0
        	break;
      		
      		default: break;
           }
     
     return 0;
     }
     
     
     
     *((volatile unsigned long *)io_p2v(GPIOAddr))=tempcon&(~(3<<(GPIOData*2)));  // GP CON = 00 as input

     templong= *((volatile unsigned long *)io_p2v( GPIOAddr+4)); 
     
     if((templong&(1<<GPIOData))!=0)
        bit=1;
      else  
        bit=0;
        
 //    printk("\nGPIOData=%x GPIO con=%x", GPIOData,*((volatile unsigned long *)io_p2v(GPIOAddr)));
     
     if (length&0x4)
      	*((volatile unsigned long *)io_p2v(GPIOAddr))=tmpold;  // Keep CON IO as before
      
     return bit;   
}

static int gpio_write(struct file *inode, const char *gdata, size_t length, loff_t *off_what)
  {
      unsigned long templong,tempcon,tmpold;
      unsigned char i;
      int GPIOAddr,GPIOData,temp_gdata[8]; 
      
      
      
      for(i=0;i<8;i++)
        temp_gdata[i]=(int)gdata[i];
      GPIOAddr=temp_gdata[0]+temp_gdata[1]*256+temp_gdata[2]*256*256+temp_gdata[3]*256*256*256;
      GPIOData=temp_gdata[4]+temp_gdata[5]*256+temp_gdata[6]*256*256+temp_gdata[7]*256*256*256;
    //  printk("\n GPIOAddr=%x  GPIOData=%x", GPIOAddr,GPIOData);    
      tempcon=*((volatile unsigned long *)io_p2v(GPIOAddr ));
      tmpold=tempcon;
      
      if (length&0x4)  //about set function11  
      {
              *((volatile unsigned long *)io_p2v(GPIOAddr))=tempcon|((3<<(GPIOData*2)));  // GP CON = 11 as FUNCTION2
              return 0;
      }

      if (length&0x2)  //about set function10  
      {
      	      *((volatile unsigned long *)io_p2v(GPIOAddr))=tempcon&(~(1<<(GPIOData*2)));  // GP CON = 10 as FUNCTION1
      	      tempcon=*((volatile unsigned long *)io_p2v(GPIOAddr ));
              *((volatile unsigned long *)io_p2v(GPIOAddr))=tempcon|((1<<(GPIOData*2+1)));  // GP CON = 10 as FUNCTION1
              return 0;
      }
      
      
      
      *((volatile unsigned long *)io_p2v(GPIOAddr))=tempcon&(~(1<<(GPIOData*2+1)));  // GP CON = 01 as output
      tempcon=*((volatile unsigned long *)io_p2v(GPIOAddr ));
      *((volatile unsigned long *)io_p2v(GPIOAddr))=tempcon|((1<<(GPIOData*2)));  // GP CON = 01 as output
      
      switch(length&0x1)
     {
      case 1:  
        templong= *((volatile unsigned long *)io_p2v( GPIOAddr+4)); 
        *((volatile unsigned long *)io_p2v(GPIOAddr+4 ))=templong|(1<<GPIOData); //GP DAT =1
//        printk("Write gpio %d\n",length);
        break;
      case 0: 
        templong= *((volatile unsigned long *)io_p2v(GPIOAddr+4 )); 
        *((volatile unsigned long *)io_p2v(GPIOAddr+4 ))=templong&(~(1<<GPIOData)); //GP DAT = 0
  //      printk(" Write gpio %d\n",length);
        break;
      default: break;
     } 
      
//      if (length&0x4)
//      	*((volatile unsigned long *)io_p2v(GPIOAddr))=tmpold;  // Keep CON IO as before
      
      return 0;
  }
                                                                               
static int __init
gpio_init(void)
{
  int ret;                                                         
   ret = register_chrdev(IOPORT_MAJOR, DEVICE_NAME, &gpio_ctl_fops);
        if(ret < 0) {
                printk(DEVICE_NAME " can't get major number\n");
                return ret;
        }
//   gpio_Major = ret;
   printk ("_____________________ board gpio registred: major= %d\n",IOPORT_MAJOR);
 
  return 0;
}         

static void __exit
gpio_cleanup(void)
{
   int ret;
                                                                                
        /*
         * Unregister the device
         */
        ret = unregister_chrdev (IOPORT_MAJOR, DEVICE_NAME);
                                                                                
        /*
         * If there's an error, report it
         */
        if (ret < 0) {
                printk ("unregister_chrdev: error %d\n", ret);
        }

}
/*
int init_module (void)
{
int ret ;
 ret=gpio_init();
}
                                                                               
void cleanup_module (void)
{
 int ret;
 ret=gpio_cleanup();
}
                                                                             
  */                                                                     
module_init(gpio_init);
module_exit(gpio_cleanup);