#include "bus.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "io.h"

#ifdef __linux__
	#ifndef ARM
		int fifos[128];
	#endif
#endif


#ifdef ARM

	int  mem_fd;
	void *gpio_map;
	 
	// I/O access
	volatile unsigned *gpio;
	
	void setup_io()
	{
		 /* open /dev/mem */
		 if ((mem_fd = open("/dev/mem", O_RDWR|O_SYNC) ) < 0) {
				printf("can't open /dev/mem \n");
				exit(-1);
		 }
	 
		 /* mmap GPIO */
		 gpio_map = mmap(
				NULL,             //Any adddress in our space will do
				BLOCK_SIZE,       //Map length
				PROT_READ|PROT_WRITE,// Enable reading & writting to mapped memory
				MAP_SHARED,       //Shared with other processes
				mem_fd,           //File to map
				GPIO_BASE         //Offset to GPIO peripheral
		 );
	 
		 close(mem_fd); //No need to keep mem_fd open after mmap
	 
		 if (gpio_map == MAP_FAILED) {
				printf("mmap error %d\n", (int)gpio_map);//errno also set!
				exit(-1);
		 }
	 
		 // Always use volatile pointer!
		 gpio = (volatile unsigned *)gpio_map;
	 
	 
	} // setup_io
#else 
	void setup_io()
	{
	}
#endif

void write_pin(int pin, int value)
{
	#ifdef __linux__
		#ifndef ARM
			char c = (value)?'1':'0';
			write(fifos[pin], &c, 1);	
		#else
			GPIO_WRITE(pin, value);
		#endif
	#else
		digitalWrite(pin, value);
	#endif
}

int read_pin(int pin)
{
	#ifdef __linux__
		#ifndef ARM
			int f = fifos[pin];
			int c=0;
			while(read(fifos[pin], &c,1)<=0)usleep(10);
			return (c=='0')?0:1;
		#else
			return GET_GPIO(pin);
		#endif
	#else
		return digitalRead(pin);
	#endif
}

void init_read_pin(int d, int clk, int ack)
{
	#ifdef __linux__
		#ifndef ARM
			fifos[d]=open("/tmp/fifodata", O_RDONLY | O_NONBLOCK);
			fifos[clk]=open("/tmp/fifoclk", 	O_RDONLY | O_NONBLOCK);
			fifos[ack]=open("/tmp/fifoack", 	O_WRONLY );
		#else
			INP_GPIO(d);
			INP_GPIO(clk);
			OUT_GPIO(ack); 
		#endif
	#else
		pinMode(d, INPUT);
		pinMode(clk, INPUT);
		pinMode(ack, OUTPUT); 
	#endif
}
void init_write_pin(int d, int clk, int ack)
{
	#ifdef __linux__
		#ifndef ARM
			fifos[d]=open("/tmp/fifoack", 	O_RDONLY  | O_NONBLOCK);
			fifos[clk]=open("/tmp/fifodata", O_WRONLY);
			fifos[ack]=open("/tmp/fifoclk", 	O_WRONLY);
		#else
			OUT_GPIO(d);
			OUT_GPIO(clk);
			INP_GPIO(ack);
		#endif
	#else
		pinMode(d, OUTPUT);
		pinMode(clk, OUTPUT);
		pinMode(ack, INPUT);
	#endif
}

void free_fifo(int d, int clk, int ack)
{
	#ifdef __linux__
		#ifndef ARM
			close(fifos[d]);
			close(fifos[clk]);
			close(fifos[ack]);
		#endif
	#endif
}