/*
 * Copyright (c) 2002,03 Bernd Walter Computer Technology
 * http://www.bwct.de
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the author nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 *
 * Thanks to FTDI for providing me the programming specs.
 *
 * $URL: https://devel.bwct.de/svn/projects/usb/fdti232/eeprom/trunk/ftdi-eeprom.c $
 * $Date: 2003-02-16 05:02:35 +0100 (Sun, 16 Feb 2003) $
 * $Author: ticso $
 * $Rev: 309 $
 */

#include <sys/ioctl.h>
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <dev/usb/usb.h>

#include "ftdi-eeprom.h"

static int fd;
static int do_write;

/*
 * ftdi-eeprom: programm to write 93c46 EEPROM devices on
 * FTDI usb chips over usb
 */
int
main(int argc, char *argv[])
{
	int ch;
	static char *devname;
	static int addr;
	union {
		u_int8_t *d8;
		u_int16_t *d16;
	} data;
	int wptr;
	u_int16_t vendor_id, product_id, release_number;
	int bus_powered, remote_wakeup;
	u_int8_t current;
	char* manufacturer_string;
	char* product_string;
	char* serial_string;
	u_int16_t checksum, tmpsum;

	while ((ch = getopt(argc, argv, "wa:f:")) != -1)
		switch (ch) {
		case 'a':
			addr = strtol(optarg, NULL, 0);
			break;
		case 'f':
			devname = optarg;
			break;
		case 'w':
			do_write = 1;
			break;
		default:
			usage();
			/* NOTREACHED */
		}
	argc -= optind;
	argv += optind;

	if (devname == NULL) {
		usage();
		/* NOTREACHED */
	}

	fd = open(devname, O_RDWR);
	if (fd < 0) {
		fprintf(stderr, "Failed to open device: %s %s\n", devname,
		    strerror(errno));
		exit(1);
	}

	data.d8 = (u_int8_t*)malloc(128);
	if (data.d8 == NULL) {
		fprintf(stderr, "failed to malloc 128 Bytes\n");
		exit(1);
	}
	bzero(data.d8, 128);

	if (do_write) {
		if (argc != 9) {
			free(data.d8);
			usage();
			/* NOTREACHED */
		}
		vendor_id = strtol(argv[0], NULL, 0);
		product_id = strtol(argv[1], NULL, 0);
		release_number = strtol(argv[2], NULL, 0);
		bus_powered = (strcmp(argv[3], "1") == 0) ? 1 : 0;
		remote_wakeup = (strcmp(argv[4], "1") == 0) ? 1 : 0;
		current = strtol(argv[5], NULL, 0) / 2;
		manufacturer_string = argv[6];
		product_string = argv[7];
		serial_string = argv[8];
		data.d16[0x2/2] = vendor_id;
		data.d16[0x4/2] = product_id;
		data.d16[0x6/2] = release_number;
		data.d8[0x8 ^ END8] = 0x80;
		data.d8[0x8 ^ END8] |= (bus_powered) ? 0 : 0x40;
		data.d8[0x8 ^ END8] |= (remote_wakeup) ? 0x20 : 0;
		data.d8[0x9 ^ END8] = current;
		wptr = 0x14;
		data.d8[0xe ^ END8] = wptr + 0x80;
		data.d8[0xf ^ END8] = strlen(manufacturer_string) * 2 + 2;
		data.d8[wptr++ ^ END8] = data.d8[0xf ^ END8];
		data.d8[wptr++ ^ END8] = 0x03;
		while (*manufacturer_string != '\0') {
			data.d16[wptr/2] = *(manufacturer_string++);
			wptr += 2;
		}
		data.d8[0x10 ^ END8] = wptr + 0x80;
		data.d8[0x11 ^ END8] = strlen(product_string) * 2 + 2;
		data.d8[wptr++ ^ END8] = data.d8[0x11 ^ END8];
		data.d8[wptr++ ^ END8] = 0x03;
		while (*product_string != '\0') {
			data.d16[wptr/2] = *(product_string++);
			wptr += 2;
		}
		data.d8[0x12 ^ END8] = wptr + 0x80;
		data.d8[0x13 ^ END8] = strlen(serial_string) * 2 + 2;
		data.d8[wptr++ ^ END8] = data.d8[0x13 ^ END8];
		data.d8[wptr++ ^ END8] = 0x03;
		while (*serial_string != '\0') {
			data.d16[wptr/2] = *(serial_string++);
			wptr += 2;
		}

		checksum = 0xaaaa;
		for (wptr = 0; wptr < 0x3f; wptr++) {
			writecell(wptr, data.d16[wptr], addr);
			tmpsum = data.d16[wptr] ^ checksum;
			checksum = tmpsum << 1; 
			if (tmpsum & 0x8000)
				checksum |= 0x01;
		}
		writecell(wptr, checksum, addr);
	}

	free(data.d8);
	close(fd);
	return 0;
}

int
writecell (int num, u_int16_t val, int addr) {
	struct usb_ctl_request request;
	int res;

	request.ucr_addr = addr;
	request.ucr_request.bmRequestType = 0x40;
	request.ucr_request.bRequest = 0x91;
	request.ucr_request.wValue[0] = val & 0xff;
	request.ucr_request.wValue[1] = val >> 8;
	request.ucr_request.wIndex[0] = num & 0xff;
	request.ucr_request.wIndex[1] = num >> 8;
	request.ucr_request.wLength[0] = 0x00;
	request.ucr_request.wLength[1] = 0x00;
	request.ucr_data = NULL;
	request.ucr_flags = 0;
	request.ucr_actlen = 0;
	if (addr)
		res = ioctl(fd, USB_REQUEST, &request);
	else
		res = ioctl(fd, USB_DO_REQUEST, &request);
	if (res < 0) {
		fprintf(stderr, "failed to write value %d into cell %d %s\n",
		    val, num, strerror(errno));
	}
	return res;
}

void
usage()
{

	fprintf(stderr, "ftdi-eeprom V1.0\n");
	fprintf(stderr, "(c) 2002,03 by Bernd Walter Computer Technology\n");
	fprintf(stderr, "All rights reserved.\n");
	fprintf(stderr,
	    "usage: ftdi-eeprom -f dev [-a addr] -w vendor_id product_id \\\n"
	    "       release_number bus_powered remote_wakeup current \\\n"
	    "       manufacturer_string product_string serial_string\n");
	exit(1);
}