/* -*- c++ -*- */
/*
 * Copyright 2003,2004,2008,2009 Free Software Foundation, Inc.
 *
 * This file is part of UHD
 *
 * GNU Radio is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3, or (at your option)
 * any later version.
 *
 * GNU Radio is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU Radio; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
*/

#include <iostream>
#include <sstream>
#include <fstream>
#include <string>
#include <cstdlib>

#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>

#include <linux/spi/spidev.h>


// Programming data for clock gen chip
static const unsigned int config_data[] = {
	0x000024,
	0x023201,
	0x000081,
	0x000400,
	0x00104c,
	0x001101,
	0x001200,
	0x001300,
	0x001414,
	0x001500,
	0x001604,
	0x001704,
	0x001807,
	0x001900,
	//0x001a00,//for debug
	0x001a32,
	0x001b12,
	0x001c44,
	0x001d00,
	0x001e00,
	0x00f062,
	0x00f162,
	0x00f262,
	0x00f362,
	0x00f462,
	0x00f562,
	0x00f662,
	0x00f762,
	0x00f862,
	0x00f962,
	0x00fa62,
	0x00fb62,
	0x00fc00,
	0x00fd00,
	0x019021,
	0x019100,
	0x019200,
	0x019333,
	0x019400,
	0x019500,
	0x019611,
	0x019700,
	0x019800,
	0x019900,
	0x019a00,
	0x019b00,
	0x01e003,
	0x01e102,
	0x023000,
	0x023201,
	0x0b0201,
	0x0b0300,
	0x001fff,
	0x0a0000,
	0x0a0100,
	0x0a0200,
	0x0a0302,
	0x0a0400,
	0x0a0504,
	0x0a060e,
	0x0a0700,
	0x0a0810,
	0x0a090e,
	0x0a0a00,
	0x0a0bf0,
	0x0a0c0b,
	0x0a0d01,
	0x0a0e90,
	0x0a0f01,
	0x0a1001,
	0x0a11e0,
	0x0a1201,
	0x0a1302,
	0x0a1430,
	0x0a1580,
	0x0a16ff,
	0x023201,
	0x0b0301,
	0x023201,
};


const unsigned int CLKGEN_SELECT = 145;


enum gpio_direction {IN, OUT};

class gpio {
	public:

	gpio(unsigned int gpio_num, gpio_direction pin_direction, bool close_action);
	~gpio();

	bool get_value();
	void set_value(bool state);

	private:

	unsigned int gpio_num;

	std::stringstream base_path;
	std::fstream value_file;
	std::fstream direction_file;
	bool close_action; // True set to input and release, false do nothing
};

class spidev {
	public:

	spidev(std::string dev_name);
	~spidev();

	void send(char *wbuf, char *rbuf, unsigned int nbytes);

	private:

	int fd;

};

gpio::gpio(unsigned int _gpio_num, gpio_direction pin_direction, bool close_action)
{
	std::fstream export_file;

	gpio_num = _gpio_num;

	export_file.open("/sys/class/gpio/export", std::ios::out);
	if (!export_file.is_open())  ///\todo Poor error handling
		std::cout << "Failed to open gpio export file." << std::endl;

	export_file << gpio_num << std::endl;

	base_path << "/sys/class/gpio/gpio" << gpio_num << std::flush;

	std::string direction_file_name;

	direction_file_name = base_path.str() + "/direction";

	direction_file.open(direction_file_name.c_str()); 
	if (!direction_file.is_open())
		std::cout << "Failed to open direction file." << std::endl;
	if (pin_direction == OUT)
		direction_file << "out" << std::endl;
	else
		direction_file << "in" << std::endl;

	std::string value_file_name;

	value_file_name = base_path.str() + "/value";

	value_file.open(value_file_name.c_str(), std::ios_base::in | std::ios_base::out);
	if (!value_file.is_open())
		std::cout << "Failed to open value file." << std::endl;
}

bool gpio::get_value()
{

	std::string val;

	std::getline(value_file, val);
	value_file.seekg(0);

	if (val == "0")
		return false;
	else if (val == "1")
		return true;
	else
		std::cout << "Data read from value file|" << val << "|" << std::endl;

	return false;
}

void gpio::set_value(bool state)
{

	if (state)
		value_file << "1" << std::endl;
	else
		value_file << "0" << std::endl;
}

gpio::~gpio()
{
	if (close_action) {
		std::fstream unexport_file;

		direction_file << "in" << std::endl;

		unexport_file.open("/sys/class/gpio/unexport", std::ios::out);
		if (!unexport_file.is_open())  ///\todo Poor error handling
			std::cout << "Failed to open gpio export file." << std::endl;

		unexport_file << gpio_num << std::endl;
		
	 }

}

spidev::spidev(std::string fname)
{
	int ret;
	int mode = 0;
	int speed = 12000;
	int bits = 24;

	fd = open(fname.c_str(), O_RDWR);

	ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
	ret = ioctl(fd, SPI_IOC_WR_MAX_SPEED_HZ, &speed);
	ret = ioctl(fd, SPI_IOC_WR_BITS_PER_WORD, &bits);
}
	

spidev::~spidev()
{
	close(fd);
}

void spidev::send(char *buf, char *rbuf, unsigned int nbytes)
{
	int ret;

	struct spi_ioc_transfer tr;
	tr.tx_buf = (unsigned long) buf;
	tr.rx_buf = (unsigned long) rbuf;
	tr.len = nbytes;
	tr.delay_usecs = 0;
	tr.speed_hz = 12000000;
	tr.bits_per_word = 24;

	ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);	

}

static void send_config_to_clkgen(gpio &chip_select, const unsigned int data[], unsigned int data_size)
{
	spidev spi("/dev/spidev1.0");
	unsigned int rbuf;

	for (unsigned int i = 0; i < data_size; i++) {

		std::cout << "sending " << std::hex << data[i] << std::endl;
		chip_select.set_value(0);
		spi.send((char *)&data[i], (char *)&rbuf, 4);
		chip_select.set_value(1);

	};
}

int main(int argc, char *argv[])
{

	gpio clkgen_select(CLKGEN_SELECT, OUT, true);

	send_config_to_clkgen(clkgen_select, config_data, sizeof(config_data)/sizeof(unsigned int));
}