csu3_am335x/EVSE/GPL/open-plc-utils-0.3/serial/baudrate.c

/*====================================================================*
 *
 *   Copyright (c) 2013 Qualcomm Atheros, Inc.
 *
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or
 *   without modification, are permitted (subject to the limitations
 *   in the disclaimer below) provided that the following conditions
 *   are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials
 *     provided with the distribution.
 *
 *   * Neither the name of Qualcomm Atheros nor the names of
 *     its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written
 *     permission.
 *
 *   NO EXPRESS OR IMPLIED LICENSES TO ANY PARTY'S PATENT RIGHTS ARE
 *   GRANTED BY THIS LICENSE. THIS SOFTWARE IS PROVIDED BY THE
 *   COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
 *   IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 *   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 *   PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
 *   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *   NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 *   HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 *   OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *--------------------------------------------------------------------*/

/*====================================================================*
 *
 *   baud_t baudrate (unsigned rate)
 *
 *   convert integer baud rate to system constant or bitmap;
 *
 *
 *   Contributor(s):
 *	Nathaniel Houghton
 *	Charles Maier
 *
 *--------------------------------------------------------------------*/

#ifndef BAUDRATE_SOURCE
#define BAUDRATE_SOURCE

#include <termios.h>
#include <errno.h>

#include "../tools/error.h"

signed baudrate (unsigned baud, speed_t * speed)

{
	static struct baud
	{
		unsigned baud;
		speed_t code;
	}
	bauds [] =
	{
		{
			0,
			B0
		},
		{
			50,
			B50
		},
		{
			75,
			B75
		},
		{
			110,
			B110
		},
		{
			134,
			B134
		},
		{
			150,
			B150
		},
		{
			200,
			B200
		},
		{
			300,
			B300
		},
		{
			600,
			B600
		},
		{
			1200,
			B1200
		},
		{
			1800,
			B1800
		},
		{
			2400,
			B2400
		},
		{
			4800,
			B4800
		},
		{
			9600,
			B9600
		},
		{
			19200,
			B19200
		},
		{
			38400,
			B38400
		},
		{
			57600,
			B57600
		},
		{
			115200,
			B115200
		},

#ifdef B230400

		{
			230400,
			B230400
		},

#endif
#ifdef B460800

		{
			460800,
			B460800
		},

#endif
#ifdef B500000

		{
			500000,
			B500000
		},

#endif
#ifdef B921600

		{
			921600,
			B921600
		},

#endif

	};
	signed lower = 0;
	signed upper = sizeof (bauds) / sizeof (struct baud);
	while (lower < upper)
	{
		signed index = (lower + upper) >> 1;
		signed order = baud - bauds [index].baud;
		if (order < 0)
		{
			upper = index - 0;
			continue;
		}
		if (order > 0)
		{
			lower = index + 1;
			continue;
		}
		*speed = bauds [index].code;
		return (0);
	}
	return (-1);
}


#endif