#include <iostream>
#include <iomanip>
#include <memory>
#include <thread>
#include <chrono>
#include <functional>
#include <fcntl.h>
#include <poll.h>
#include <unistd.h>


#define I2C_SDA  43//GPIO1_B3
#define I2C_SCL  44//GPIO1_B4
#define I2C_INT  52

typedef unsigned char UINT8;
typedef unsigned short UINT16;

#define  STATUS_SUCCESS	0
#define  STATUS_FAILURE -1

#define CH455_GET_KEY	0x0700					// 获取按键,返回按键代码
#define CH455_SYSOFF	0x0400                  // 关闭显示、关闭键盘

#define		CH455_I2C_ADDR		0x40			// CH455的地址
#define		CH455_I2C_MASK		0x3E			// CH455的高字节命令掩码

#define CH455_BIT_ENABLE	0x01
//#define CH455_BIT_ENABLE	0x03		       // 开启/关闭位
#define CH455_BIT_SLEEP		0x04		      // 睡眠控制位


#define CH455_SYSON		( CH455_SYSOFF | CH455_BIT_ENABLE )
#define CH455_SLEEPOFF	    CH455_SYSOFF	// 关闭睡眠
#define CH455_SLEEPON	    (CH455_SYSOFF|CH455_BIT_SLEEP)	// 开启睡眠

static unsigned char TxBuf[24] = {0};
static unsigned char RxBuf[24] = {0};

void CH455_I2c_Stop(void);
void CH455_I2C_WrByte(unsigned char IIC_Byte);

void delay_us(int i)
{
    int j,k;
    for(j=0;j<i;j++)
        for(k=0;k<10;k++);
}

void initGpio(int addr)  
{  
    //printf("开始创建GPIO%d节点\n", addr);
    FILE * fp =fopen("/sys/class/gpio/export","w");  
    if (fp == NULL)  
        perror("export open filed");  
    else  
        fprintf(fp,"%d",addr);  
    
    fclose(fp);  
    //printf("结束创建GPIO%d节点\n", addr);
} 

//设置为gpio方向
void setGpioDirection(int addr,char *direction)  
{  
    //printf("设置第GPIO%d为out模式\n",addr);
    char path[100] = {0};  
    sprintf(path,"/sys/class/gpio/gpio%d/direction",addr);  
    FILE * fp =fopen(path,"w");  
    if (fp == NULL)  
        perror("direction open filed");  
    else  
        fprintf(fp,"%s",direction);  
    fclose(fp); 
    //printf("结束设置第GPIO%d为out模式\n",addr);
} 

//设置gpio的电平
void set_gpioValue(int addr, int value)
{
    //printf("设置GPIO%d为%d\n", addr, value);
    char path[64];      
    snprintf(path, sizeof(path), "/sys/class/gpio/gpio%d/value", addr);
    FILE *fp = fopen(path, "w");
    if (fp == NULL)  
        perror("direction open filed");  
    else
        fprintf(fp, "%d", value);
    fclose(fp);
    //printf("结束设置GPIO%d位置为%d\n", addr, value);
}

void IOWR_OUT(int addr, int val)
{
    initGpio(addr);
    setGpioDirection(addr, "out");
    set_gpioValue(addr, val);
}

void IOWR_IN(int addr, int val)
{
    initGpio(addr);
    setGpioDirection(addr, "in");
    set_gpioValue(addr, val);
}

//读gpio节点状态
int IORD(int addr)
{
    char path[64];  
    char value_str[3];  
  
    snprintf(path, sizeof(path), "/sys/class/gpio/gpio%d/value",addr);
    //printf("/sys/class/gpio/gpio%d/value", addr);  
    FILE *fp = fopen(path, "r");

    //fd = open(path, O_RDONLY);  
    if (fp == NULL) 
    {  
        printf("Failed to open gpio value for reading!");  
        return -1;  
    } 
    if (fread(value_str,sizeof(char),3,fp) < 0) 
    {  
        perror("Failed to read value!");  
        return -1;  
    }  
  
    fclose(fp); 
    //printf("读取GPIO状态结束\n"); 
    return (atoi(value_str));  
}

//开始位
void CH455_I2c_Start(void)
{
    IOWR_OUT(I2C_SDA, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SDA, 0);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
}

//结束位
void CH455_I2c_Stop(void)
{
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
    IOWR_OUT(I2C_SDA, 0);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SDA, 1);
    delay_us(5);
}


//主控端写入一个字节到从机
void CH455_I2C_WrByte(unsigned char IIC_Byte)
{
    unsigned char i;
    for(i=0; i<8; i++)
    {
        //IOWR(I2C_SCL, 0); //钳住I2C总线，准备发送数据
        if(IIC_Byte & 0x80)
            IOWR_OUT(I2C_SDA, 1);
        else
            IOWR_OUT(I2C_SDA, 0);
        delay_us(5);
        IOWR_OUT(I2C_SCL, 1);
        delay_us(5);
        IOWR_OUT(I2C_SCL, 0);
        delay_us(5);
        IIC_Byte<<=1;
    }
    delay_us(5);
    IOWR_OUT(I2C_SDA, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
}

//主控端对从机读取一个字节
static unsigned char CH455_I2C_RdByte(void) //读取一个字节数据
{
    unsigned char i = 0;
    unsigned char bytedata = 0;
    delay_us(5);
    //将数据设置为输入模式
    IOWR_IN(I2C_SDA, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
    for(i=0; i<8; i++)
    {
        IOWR_OUT(I2C_SCL, 1);
        delay_us(5);
        bytedata <<= 1;
        delay_us(5);
        bytedata = bytedata | (IORD(I2C_SDA));
        delay_us(5);
        IOWR_OUT(I2C_SCL, 0);
        delay_us(5);
    }
    IOWR_OUT(I2C_SDA, 1); //数据线设置回输出模式
    delay_us(5);
    IOWR_OUT(I2C_SCL, 1);
    delay_us(5);
    IOWR_OUT(I2C_SCL, 0);
    delay_us(5);
    return (bytedata);//返回数据
}

//写命令
static unsigned char CH455_Write( UINT16 cmd)
{
	printf("CH455_Write start...\n");
	CH455_I2c_Start();//启动总线
    printf("CH455_Write first byte= %02x\n",((UINT8)(cmd>>7)&CH455_I2C_MASK)|CH455_I2C_ADDR);
	printf("CH455_Write second byte= %02x\n",(UINT8)cmd);
    CH455_I2C_WrByte(((UINT8)(cmd>>7)&CH455_I2C_MASK)|CH455_I2C_ADDR);
    CH455_I2C_WrByte((UINT8)cmd); //发送数据
    CH455_I2c_Stop();//结束总线
    printf("CH455_Write end...\n");
	printf("\n");
    return 1;
}

static unsigned char CH455_Read(void)//读取按键值
{
	printf("CH455_Read start...\n");
	UINT8 keycode;
    CH455_I2c_Start();      //启动总线
	printf("write byte= %02x\n",(UINT8)(CH455_GET_KEY>>7)&CH455_I2C_MASK|0x01|CH455_I2C_ADDR); 
    CH455_I2C_WrByte((UINT8)(CH455_GET_KEY>>7)&CH455_I2C_MASK|0x01|CH455_I2C_ADDR);
    keycode = CH455_I2C_RdByte();   //读取数据
    printf("read byte= %02x\n",keycode);
    CH455_I2c_Stop();     //结束总线
	printf("CH455_Read end...\n");
	printf("\n");
    return keycode;
}

void key_Inter(void) 
{
    int ret;
    int val = 0;
    char buf[8];
    int num;
	UINT16 key_value;
	pollfd pfd;
	pfd.fd = -1;
	pfd.fd = open("/sys/class/gpio/gpio52/value", O_RDONLY);
	if (pfd.fd > 0)
		printf("huagao::open sucess,fd = %d\n",pfd.fd);
	else
		printf("huagao::open failed,fd = %d\n",pfd.fd);
	pfd.events = POLLPRI;
	num = read(pfd.fd, buf, 8); // This is to clear the avaible read
	for(int i=0;i<8;i++)
		printf("huagao::buf[%d] = %d\n",i,buf[i]);

    ret = CH455_Write(CH455_SYSON);
    printf("CH455_SYSON = %02x\n",(CH455_SYSON));
    printf("CH455_Read() = %02x\n", CH455_Read());
	key_value = 0xff;
	while(1) {
		ret = poll(&pfd, 1, 1000);
		if (ret > 0)
		{
			printf("--------------------------------------------\n");
			printf("huagao::poll get date.\n");
			printf("huagao::poll ret = %d\n",ret);
			/*
			POLLIN: 有普通数据或者优先数据可读
			POLLRDNORM: 有普通数据可读
			POLLRDBAND: 有优先数据可读
			POLLPRI: 有紧急数据可读
			POLLOUT: 有普通数据可写
			POLLWRNORM: 有普通数据可写
			POLLWRBAND: 有紧急数据可写
			POLLERR: 有错误发生
			POLLHUP: 有描述符挂起事件发生
			POLLNVAL: 描述符非法
			*/
			if (pfd.revents & POLLPRI)
			{
				lseek(pfd.fd, 0, SEEK_SET);
				num = read(pfd.fd, buf, 8);
				buf[num - 1] = '\0';
				ret = atoi(buf);
				for(int i=0;i<8;i++)
					printf("huagao::buf[%d] = %d\n",i,buf[i]);
				printf("huagao::atoi(buf) ret = %d\n",ret);
			}
			key_value = CH455_Read();
			printf("CH455_Read() = %02x\n", key_value);
			printf("--------------------------------------------\n");
			printf("\n");
		}	
		else if(ret == 0)
		{
			printf("--------------------------------------------\n");
			printf("huagao::ret = %d\n",ret);
			printf("huagao::poll time out.\n");
			printf("--------------------------------------------\n");
			printf("\n");
		}		
		else
		{
			printf("--------------------------------------------\n");
			printf("huagao::ret = %d\n",ret);
			printf("huagao::poll err.\n");
			printf("--------------------------------------------\n");
			printf("\n");
		}		
			
	}
}
int main(void)
{
	system("echo 52 > /sys/class/gpio/export");
	system("echo in > /sys/class/gpio/gpio52/direction");
	system("echo falling > /sys/class/gpio/gpio52/edge");
	key_Inter();
    return 0;
}