/*

 * libusb example program to manipulate U.are.U 4000B fingerprint scanner.

 * Copyright © 2007 Daniel Drake <dsd@gentoo.org>

 *

 * Basic image capture program only, does not consider the powerup quirks or

 * the fact that image encryption may be enabled. Not expected to work

 * flawlessly all of the time.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include <errno.h>

#include <signal.h>

#include <string.h>

#include <stdio.h>

#include <stdlib.h>

#include "libusb.h"

#define EP_INTR			(1 | LIBUSB_ENDPOINT_IN)

#define EP_DATA			(2 | LIBUSB_ENDPOINT_IN)

#define CTRL_IN			(LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_IN)

#define CTRL_OUT		(LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_ENDPOINT_OUT)

#define USB_RQ			0x04

#define INTR_LENGTH		64

enum {

	MODE_INIT = 0x00,

	MODE_AWAIT_FINGER_ON = 0x10,

	MODE_AWAIT_FINGER_OFF = 0x12,

	MODE_CAPTURE = 0x20,

	MODE_SHUT_UP = 0x30,

	MODE_READY = 0x80,

};

static int next_state(void);

enum {

	STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON = 1,

	STATE_AWAIT_IRQ_FINGER_DETECTED,

	STATE_AWAIT_MODE_CHANGE_CAPTURE,

	STATE_AWAIT_IMAGE,

	STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF,

	STATE_AWAIT_IRQ_FINGER_REMOVED,

};

static int state = 0;

static struct libusb_device_handle *devh = NULL;

static unsigned char imgbuf[0x1b340];

static unsigned char irqbuf[INTR_LENGTH];

static struct libusb_transfer *img_transfer = NULL;

static struct libusb_transfer *irq_transfer = NULL;

static int img_idx = 0;

static int do_exit = 0;

static int find_dpfp_device(void)

{

	devh = libusb_open_device_with_vid_pid(NULL, 0x05ba, 0x000a);

	return devh ? 0 : -EIO;

}

static int print_f0_data(void)

{

	unsigned char data[0x10];

	int r;

	unsigned int i;

	r = libusb_control_transfer(devh, CTRL_IN, USB_RQ, 0xf0, 0, data,

		sizeof(data), 0);

	if (r < 0) {

		fprintf(stderr, "F0 error %d\n", r);

		return r;

	}

	if ((unsigned int) r < sizeof(data)) {

		fprintf(stderr, "short read (%d)\n", r);

		return -1;

	}

	printf("F0 data:");

	for (i = 0; i < sizeof(data); i++)

		printf("%02x ", data[i]);

	printf("\n");

	return 0;

}

static int get_hwstat(unsigned char *status)

{

	int r;

	r = libusb_control_transfer(devh, CTRL_IN, USB_RQ, 0x07, 0, status, 1, 0);

	if (r < 0) {

		fprintf(stderr, "read hwstat error %d\n", r);

		return r;

	}

	if ((unsigned int) r < 1) {

		fprintf(stderr, "short read (%d)\n", r);

		return -1;

	}

	printf("hwstat reads %02x\n", *status);

	return 0;

}

static int set_hwstat(unsigned char data)

{

	int r;

	printf("set hwstat to %02x\n", data);

	r = libusb_control_transfer(devh, CTRL_OUT, USB_RQ, 0x07, 0, &data, 1, 0);

	if (r < 0) {

		fprintf(stderr, "set hwstat error %d\n", r);

		return r;

	}

	if ((unsigned int) r < 1) {

		fprintf(stderr, "short write (%d)", r);

		return -1;

	}

	return 0;

}

static int set_mode(unsigned char data)

{

	int r;

	printf("set mode %02x\n", data);

	r = libusb_control_transfer(devh, CTRL_OUT, USB_RQ, 0x4e, 0, &data, 1, 0);

	if (r < 0) {

		fprintf(stderr, "set mode error %d\n", r);

		return r;

	}

	if ((unsigned int) r < 1) {

		fprintf(stderr, "short write (%d)", r);

		return -1;

	}

	return 0;

}

static void LIBUSB_CALL cb_mode_changed(struct libusb_transfer *transfer)

{

	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {

		fprintf(stderr, "mode change transfer not completed!\n");

		do_exit = 2;

	}

	printf("async cb_mode_changed length=%d actual_length=%d\n",

		transfer->length, transfer->actual_length);

	if (next_state() < 0)

		do_exit = 2;

}

static int set_mode_async(unsigned char data)

{

	unsigned char *buf = (unsigned char*) malloc(LIBUSB_CONTROL_SETUP_SIZE + 1);

	struct libusb_transfer *transfer;

	if (!buf)

		return -ENOMEM;

	transfer = libusb_alloc_transfer(0);

	if (!transfer) {

		free(buf);

		return -ENOMEM;

	}

	printf("async set mode %02x\n", data);

	libusb_fill_control_setup(buf, CTRL_OUT, USB_RQ, 0x4e, 0, 1);

	buf[LIBUSB_CONTROL_SETUP_SIZE] = data;

	libusb_fill_control_transfer(transfer, devh, buf, cb_mode_changed, NULL,

		1000);

	transfer->flags = LIBUSB_TRANSFER_SHORT_NOT_OK

		| LIBUSB_TRANSFER_FREE_BUFFER | LIBUSB_TRANSFER_FREE_TRANSFER;

	return libusb_submit_transfer(transfer);

}

static int do_sync_intr(unsigned char *data)

{

	int r;

	int transferred;

	r = libusb_interrupt_transfer(devh, EP_INTR, data, INTR_LENGTH,

		&transferred, 1000);

	if (r < 0) {

		fprintf(stderr, "intr error %d\n", r);

		return r;

	}

	if (transferred < INTR_LENGTH) {

		fprintf(stderr, "short read (%d)\n", r);

		return -1;

	}

	printf("recv interrupt %04x\n", *((uint16_t *) data));

	return 0;

}

static int sync_intr(unsigned char type)

{

	int r;

	unsigned char data[INTR_LENGTH];

	while (1) {

		r = do_sync_intr(data);

		if (r < 0)

			return r;

		if (data[0] == type)

			return 0;

	}

}

static int save_to_file(unsigned char *data)

{

	FILE *fd;

	char filename[64];

	snprintf(filename, sizeof(filename), "finger%d.pgm", img_idx++);

	fd = fopen(filename, "w");

	if (!fd)

		return -1;

	fputs("P5 384 289 255 ", fd);

	(void) fwrite(data + 64, 1, 384*289, fd);

	fclose(fd);

	printf("saved image to %s\n", filename);

	return 0;

}

static int next_state(void)

{

	int r = 0;

	printf("old state: %d\n", state);

	switch (state) {

	case STATE_AWAIT_IRQ_FINGER_REMOVED:

		state = STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON;

		r = set_mode_async(MODE_AWAIT_FINGER_ON);

		break;

	case STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_ON:

		state = STATE_AWAIT_IRQ_FINGER_DETECTED;

		break;

	case STATE_AWAIT_IRQ_FINGER_DETECTED:

		state = STATE_AWAIT_MODE_CHANGE_CAPTURE;

		r = set_mode_async(MODE_CAPTURE);

		break;

	case STATE_AWAIT_MODE_CHANGE_CAPTURE:

		state = STATE_AWAIT_IMAGE;

		break;

	case STATE_AWAIT_IMAGE:

		state = STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF;

		r = set_mode_async(MODE_AWAIT_FINGER_OFF);

		break;

	case STATE_AWAIT_MODE_CHANGE_AWAIT_FINGER_OFF:

		state = STATE_AWAIT_IRQ_FINGER_REMOVED;

		break;

	default:

		printf("unrecognised state %d\n", state);

	}

	if (r < 0) {

		fprintf(stderr, "error detected changing state\n");

		return r;

	}

	printf("new state: %d\n", state);

	return 0;

}

static void LIBUSB_CALL cb_irq(struct libusb_transfer *transfer)

{

	unsigned char irqtype = transfer->buffer[0];

	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {

		fprintf(stderr, "irq transfer status %d?\n", transfer->status);

		do_exit = 2;

		libusb_free_transfer(transfer);

		irq_transfer = NULL;

		return;

	}

	printf("IRQ callback %02x\n", irqtype);

	switch (state) {

	case STATE_AWAIT_IRQ_FINGER_DETECTED:

		if (irqtype == 0x01) {

			if (next_state() < 0) {

				do_exit = 2;

				return;

			}

		} else {

			printf("finger-on-sensor detected in wrong state!\n");

		}

		break;

	case STATE_AWAIT_IRQ_FINGER_REMOVED:

		if (irqtype == 0x02) {

			if (next_state() < 0) {

				do_exit = 2;

				return;

			}

		} else {

			printf("finger-on-sensor detected in wrong state!\n");

		}

		break;

	}

	if (libusb_submit_transfer(irq_transfer) < 0)

		do_exit = 2;

}

static void LIBUSB_CALL cb_img(struct libusb_transfer *transfer)

{

	if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {

		fprintf(stderr, "img transfer status %d?\n", transfer->status);

		do_exit = 2;

		libusb_free_transfer(transfer);

		img_transfer = NULL;

		return;

	}

	printf("Image callback\n");

	save_to_file(imgbuf);

	if (next_state() < 0) {

		do_exit = 2;

		return;

	}

	if (libusb_submit_transfer(img_transfer) < 0)

		do_exit = 2;

}

static int init_capture(void)

{

	int r;

	r = libusb_submit_transfer(irq_transfer);

	if (r < 0)

		return r;

	r = libusb_submit_transfer(img_transfer);

	if (r < 0) {

		libusb_cancel_transfer(irq_transfer);

		while (irq_transfer)

			if (libusb_handle_events(NULL) < 0)

				break;

		return r;

	}

	/* start state machine */

	state = STATE_AWAIT_IRQ_FINGER_REMOVED;

	return next_state();

}

static int do_init(void)

{

	unsigned char status;

	int r;

	r = get_hwstat(&status);

	if (r < 0)

		return r;

	if (!(status & 0x80)) {

		r = set_hwstat(status | 0x80);

		if (r < 0)

			return r;

		r = get_hwstat(&status);

		if (r < 0)

			return r;

	}

	status &= ~0x80;

	r = set_hwstat(status);

	if (r < 0)

		return r;

	r = get_hwstat(&status);

	if (r < 0)

		return r;

	r = sync_intr(0x56);

	if (r < 0)

		return r;

	return 0;

}

static int alloc_transfers(void)

{

	img_transfer = libusb_alloc_transfer(0);

	if (!img_transfer)

		return -ENOMEM;

	irq_transfer = libusb_alloc_transfer(0);

	if (!irq_transfer)

		return -ENOMEM;

	libusb_fill_bulk_transfer(img_transfer, devh, EP_DATA, imgbuf,

		sizeof(imgbuf), cb_img, NULL, 0);

	libusb_fill_interrupt_transfer(irq_transfer, devh, EP_INTR, irqbuf,

		sizeof(irqbuf), cb_irq, NULL, 0);

	return 0;

}

static void sighandler(int signum)

{

	(void)signum;

	do_exit = 1;

}

int main(void)

{

	struct sigaction sigact;

	int r;

	r = libusb_init(NULL);

	if (r < 0) {

		fprintf(stderr, "failed to initialise libusb\n");

		exit(1);

	}

	r = find_dpfp_device();

	if (r < 0) {

		fprintf(stderr, "Could not find/open device\n");

		goto out;

	}

	r = libusb_claim_interface(devh, 0);

	if (r < 0) {

		fprintf(stderr, "usb_claim_interface error %d\n", r);

		goto out;

	}

	printf("claimed interface\n");

	r = print_f0_data();

	if (r < 0)

		goto out_release;

	r = do_init();

	if (r < 0)

		goto out_deinit;

	/* async from here onwards */

	r = alloc_transfers();

	if (r < 0)

		goto out_deinit;

	r = init_capture();

	if (r < 0)

		goto out_deinit;

	sigact.sa_handler = sighandler;

	sigemptyset(&sigact.sa_mask);

	sigact.sa_flags = 0;

	sigaction(SIGINT, &sigact, NULL);

	sigaction(SIGTERM, &sigact, NULL);

	sigaction(SIGQUIT, &sigact, NULL);

	while (!do_exit) {

		r = libusb_handle_events(NULL);

		if (r < 0)

			goto out_deinit;

	}

	printf("shutting down...\n");

	if (irq_transfer) {

		r = libusb_cancel_transfer(irq_transfer);

		if (r < 0)

			goto out_deinit;

	}

	if (img_transfer) {

		r = libusb_cancel_transfer(img_transfer);

		if (r < 0)

			goto out_deinit;

	}

	while (irq_transfer || img_transfer)

		if (libusb_handle_events(NULL) < 0)

			break;

	if (do_exit == 1)

		r = 0;

	else

		r = 1;

out_deinit:

	libusb_free_transfer(img_transfer);

	libusb_free_transfer(irq_transfer);

	set_mode(0);

	set_hwstat(0x80);

out_release:

	libusb_release_interface(devh, 0);

out:

	libusb_close(devh);

	libusb_exit(NULL);

	return r >= 0 ? r : -r;

}