#include<stdio.h>
#include<unistd.h>
#include<sys/mman.h>
#include<sys/types.h>
#include<sys/stat.h>
#include<fcntl.h>

#define PIO_BASE_ADDRESS    0x01C20800 


typedef struct
{
    unsigned int CFG[4];
    unsigned int DAT ;
    unsigned int DRV0;
    unsigned int DRV1;
    unsigned int PUL0;
    unsigned int PUL1;
}PIO_Struct;

typedef struct
{
    PIO_Struct Pn[7];
}PIO_Map;

typedef enum
{
    PA = 0,
    PB = 1,
    PC = 2,
    PD = 3,
    PE = 4,
    PF = 5,
    PG = 6,
}PORT;

typedef enum
{
    IN          = 0x00,
    OUT         = 0x01,
    AUX         = 0x02,
    INT         = 0x06,
    DISABLE         = 0x07,
}PIN_MODE;


PIO_Map *PIO = NULL;
unsigned int *gpio_map;


void GPIO_Init(void) 
{ 
    unsigned int fd; 
    unsigned int addr_start, addr_offset; 
    unsigned int PageSize, PageMask;

    if((fd = open("/dev/mem",O_RDWR)) == -1)
    {
        printf("open error\r\n");
        return;
    }

    PageSize = sysconf(_SC_PAGESIZE);       //頁大小
    PageMask = (~(PageSize-1));         //頁掩碼
//  printf("PageSize:%d,PageMask:%.8X\r\n",PageSize,PageMask);

    addr_start = PIO_BASE_ADDRESS & PageMask;
    addr_offset = PIO_BASE_ADDRESS & ~PageMask;
//  printf("addr_start:%.8X,addr_offset:%.8X\r\n",addr_start,addr_offset);

    if((gpio_map = mmap(NULL,PageSize*2,PROT_READ|PROT_WRITE, MAP_SHARED,fd,addr_start)) == NULL)
    {
//      printf("mmap error\r\n");
        close(fd);
        return;
    }
//  printf("gpio_map:%.8X\r\n",gpio_map);

    PIO = (PIO_Map *)((unsigned int)gpio_map + addr_offset);
//  printf("PIO:%.8X\r\n",PIO);

    close(fd);
}

void GPIO_ConfigPin(PORT port,unsigned int pin,PIN_MODE mode) 
{ 
    if (gpio_map == NULL) 
        return; 
    PIO->Pn[port].CFG[pin / 8] &= ~((unsigned int)0x07 << pin % 8 * 4); 
    PIO->Pn[port].CFG[pin / 8] |= ((unsigned int)mode << pin % 8 * 4);
}

void GPIO_SetPin(PORT port,unsigned int pin,unsigned int level) 
{ 
    if (gpio_map == NULL) 
        return; 
    if(level) PIO->Pn[port].DAT |= (1 << pin); 
    else PIO->Pn[port].DAT &= ~(1 << pin); 
}


void main()
{
    char i;

//  printf("this is main!\n\n");
    
    GPIO_Init();
    
    GPIO_ConfigPin(PE,5,OUT);
    
//  for(i=0;i<150;i++)
    {
        GPIO_SetPin(PE,5,1);
//      sleep(0.1);
//      GPIO_SetPin(PE,5,0);
//      sleep(0.1);
    }
}