/**
 * \file
 * <!--
 * This file is part of BeRTOS.
 *
 * Bertos 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * As a special exception, you may use this file as part of a free software
 * library without restriction.  Specifically, if other files instantiate
 * templates or use macros or inline functions from this file, or you compile
 * this file and link it with other files to produce an executable, this
 * file does not by itself cause the resulting executable to be covered by
 * the GNU General Public License.  This exception does not however
 * invalidate any other reasons why the executable file might be covered by
 * the GNU General Public License.
 *
 * Copyright 2005 Develer S.r.l. (http://www.develer.com/)
 * -->
 *
 *
 * \brief MCP41xxx digital potentiomenter driver (implementation)
 *
 * \author Francesco Sacchi <batt@develer.com>
 */

#include "hw/hw_mcp41.h"

#include <cfg/macros.h>
#include <cfg/compiler.h>

#include <drv/timer.h>
#include <drv/mcp41.h>
#include <io/kfile.h>

static KFile *ch;

/**
 * Set resitance for digital pot \a dev
 */
void mcp41_setResistance(Mcp41Dev dev, mcp41_res_t res)
{
	MCP41_ON(dev);
	/* send command byte */
	kfile_putc(MCP41_WRITE_DATA, ch);
	kfile_putc(((MCP41_HW_MAX * (uint32_t)res)  + (MCP41_MAX / 2)) / MCP41_MAX, ch);
	kfile_flush(ch);

	MCP41_OFF(dev);
}


/**
 * Initialize mcp41 potentiometer driver
 */
void mcp41_init(KFile *_ch)
{
	Mcp41Dev dev;

	/* Init all potentiometer ports */
	for (dev = 0; dev < MCP41_CNT; dev++)
	{
		SET_MCP41_DDR(dev);
		MCP41_OFF(dev);
	}

	ch = _ch;
}