/*
 * This module handles the establishment of serial communication
 * with the target, i.e., the host-side termios stuff.
 */

#include <sys/types.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <termios.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include "baudrate.h"

char *target_ttydev;
int target_fd;
struct termios target_termios;

struct baudrate baud_rate_table[] = {
	/* the first listed rate will be our default */
	{"115200",	B115200,	0},
	{"57600",	B57600,		1},
	{"38400",	B38400,		2},
	{"19200",	B19200,		4},
	/* non-standard high baud rates "remapped" by CP2102 usb2serial IC */
	{"812500",	B921600,	-1},
	{"406250",	B460800,	-1},
	{"203125",	B230400,	-1},
	/* table search terminator */
	{NULL,		B0,		-1},
};
struct baudrate *current_baud_rate;

open_target_serial()
{
	target_fd = open(target_ttydev, O_RDWR|O_NONBLOCK);
	if (target_fd < 0) {
		perror(target_ttydev);
		exit(1);
	}
	target_termios.c_iflag = IGNBRK;
	target_termios.c_oflag = 0;
	target_termios.c_cflag = CLOCAL|HUPCL|CREAD|CS8;
	target_termios.c_lflag = 0;
	target_termios.c_cc[VMIN] = 1;
	target_termios.c_cc[VTIME] = 0;
	/* start at B19200, as that's what we'll need to use initially */
	cfsetispeed(&target_termios, B19200);
	cfsetospeed(&target_termios, B19200);
	if (tcsetattr(target_fd, TCSAFLUSH, &target_termios) < 0) {
		perror("initial tcsetattr on target");
		exit(1);
	}
	ioctl(target_fd, TIOCEXCL);
	return 0;
}

struct baudrate *
find_baudrate_by_name(srch_name)
	char *srch_name;
{
	struct baudrate *br;

	for (br = baud_rate_table; br->name; br++)
		if (!strcmp(br->name, srch_name))
			break;
	if (br->name)
		return(br);
	else {
		fprintf(stderr, "error: baud rate \"%s\" not known\n",
			srch_name);
		return(NULL);
	}
}

switch_baud_rate(br)
	struct baudrate *br;
{
	cfsetispeed(&target_termios, br->termios_code);
	cfsetospeed(&target_termios, br->termios_code);
	if (tcsetattr(target_fd, TCSAFLUSH, &target_termios) < 0) {
		perror("tcsetattr to switch baud rate");
		exit(1);
	}
	current_baud_rate = br;
}