/*
 * Copyright (C) 2006 Eric Biederman (ebiederm@xmission.com)
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License version
 *	2 as published by the Free Software Foundation.
 *
 *      gcc -Wall -o ./usbtest ./usbtest.c -lusb
 */
#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <usb.h>

#define DEBUG_DEVICE_MAX 8

#ifndef USB_DT_DEBUG
#define USB_DT_DEBUG	10
#endif
#ifndef USB_FT_DEBUG_MODE
#define USB_FT_DEBUG_MODE	6
#endif 
#define CTRL_TIMEOUT	(5*1000)	/* milliseconds */
#define WRITE_TIMEOUT	(60*1000*1000)	/* 1 minute */

struct usb_debug_descriptor {
	uint8_t	bLength;
	uint8_t bDescriptorType;
	uint8_t bDebugInEndpoint;
	uint8_t bDebugOutEndpoint;
} __attribute__ ((packed));


static void die(char *fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);
	vfprintf(stderr, fmt, ap);
	va_end(ap);
	fflush(stderr);
	fflush(stdout);
	exit(1);
}


static struct usb_device *next_debug_device(struct usb_device *dev,
	struct usb_debug_descriptor *debug)
{
	struct usb_bus *bus;
	if (dev) {
		bus = dev->bus;
		goto next;
	}
	for (bus = usb_busses; bus; bus = bus->next) {
		for (dev = bus->devices; dev; dev = dev->next) {
			struct usb_dev_handle *handle;
			int ret;
#if 1
			printf("%02x:%02x\n",
				dev->descriptor.idVendor,
				dev->descriptor.idProduct);
#endif
			handle = usb_open(dev);
			if (!handle)
				goto next;
			ret = usb_get_descriptor(handle, USB_DT_DEBUG, 0,
				debug, sizeof(*debug));
			usb_close(handle);
#if 1
			printf("ret: %d\n", ret);
#endif
			if (ret == sizeof(*debug))
				return dev;
next:
			;
		}
	}
	return NULL;
}

static int usb_set_debug_mode(usb_dev_handle *handle)
{
	return usb_control_msg(handle, USB_TYPE_STANDARD | USB_RECIP_DEVICE,
		USB_REQ_SET_FEATURE, USB_FT_DEBUG_MODE, 0, NULL, 0,
		CTRL_TIMEOUT);
		
}

static int usb_unconfigure(usb_dev_handle *handle)
{
	return usb_control_msg(handle, USB_TYPE_STANDARD | USB_RECIP_DEVICE,
		USB_REQ_SET_CONFIGURATION, 0, 0, NULL, 0,
		CTRL_TIMEOUT);
}


static int usb_debug_read(struct usb_device *dev,
				struct usb_debug_descriptor *debug)
{
	struct usb_dev_handle *handle;
	char buf[DEBUG_DEVICE_MAX];
	int iface, i, j;
	int ret = -1;

	/* Find the interface to claim! */
	iface = -1;
	for (i = 0; i < dev->config->interface->num_altsetting; i++) {
		struct usb_interface_descriptor *face;
		face = &dev->config->interface->altsetting[i];
		for (j = 0; j < face->bNumEndpoints; j++) {
			if (face->endpoint[j].bEndpointAddress == 
			    debug->bDebugInEndpoint) {
				iface = face->bInterfaceNumber;
				printf("wMaxPacketSize: %u iface: %d\n",
					face->endpoint[j].bEndpointAddress,
					iface);
				goto found_iface;
			}
		}
	}
	goto out;
found_iface:

	handle = usb_open(dev);
	if (!handle)
		goto out;
	if ((ret = usb_claim_interface(handle, iface)) < 0)
		goto out_close;
	if ((ret = usb_set_debug_mode(handle)) < 0)
		goto out_release;
	for (;;) {
		ret = usb_bulk_read(handle, debug->bDebugInEndpoint,
			buf, sizeof(buf), 1000000);
		if (ret < 0)
			goto out_release;
		printf("%d:%*.*s", ret, ret, ret, buf);
	}
out_release:
	usb_release_interface(handle, iface);
out_close:	
	usb_close(handle);
out:
	return ret;
}


static int usb_debug_write(struct usb_device *dev,
				struct usb_debug_descriptor *debug)
{
	struct usb_dev_handle *handle;
	char buf[DEBUG_DEVICE_MAX];
	int iface, i, j;
	int ret;

	ret = -1;
	/* Find the interface to claim! */
	iface = -1;
	for (i = 0; i < dev->config->interface->num_altsetting; i++) {
		struct usb_interface_descriptor *face;
		face = &dev->config->interface->altsetting[i];
		for (j = 0; j < face->bNumEndpoints; j++) {
			if (face->endpoint[j].bEndpointAddress == 
			    debug->bDebugOutEndpoint) {
				iface = face->bInterfaceNumber;
				printf("wMaxPacketSize: %u iface: %d\n",
					face->endpoint[j].bEndpointAddress,
					iface);
				goto found_iface;
			}
		}
	}
	goto out;
found_iface:
	handle = usb_open(dev);
	if (!handle)
		goto out;
	if ((ret = usb_claim_interface(handle, iface)) < 0)
		goto out_close;
	if ((ret = usb_set_debug_mode(handle)) < 0)
		goto out_release;
	for (;;) {
		if ((ret = read(STDIN_FILENO, buf, sizeof(buf))) <= 0)
			goto out_shutdown;

#if 1
		printf("%d:%*.*s", ret, ret, ret, buf);
#endif
		ret = usb_bulk_write(handle, debug->bDebugOutEndpoint,
			buf, ret, WRITE_TIMEOUT);
#if 1
		printf("usb_bulk_write: %d\n", ret);
#endif
		if (ret < 0)
			goto out_shutdown;
	}
out_shutdown:
	usb_unconfigure(handle);
out_release:
	usb_release_interface(handle, iface);
out_close:	
	usb_close(handle);
out:
	return ret;
}

enum debug_op {
	DEBUG_LIST = 0,
	DEBUG_REDIR = 1,
	DEBUG_READ  = 2,
	DEBUG_WRITE = 3,
};
int main(int argc, char **argv)
{
	struct usb_device *dev;
	struct usb_debug_descriptor debug_desc;
	int i;
	int wanted_bus, wanted_dev;
	int wanted_vendor, wanted_product;
	enum debug_op op;

	op = DEBUG_REDIR;
	wanted_bus = wanted_dev = -1;
	wanted_vendor = wanted_product = -1;
	for (i = 1; i < argc; i++) {
		if (strcmp(argv[i], "-s") == 0) {
			char *colon;
			i++;
			if (i >= argc)
				die("missing argument");
			colon = strchr(argv[i], ':');
			if (!colon)
				wanted_dev = strtoul(argv[i], NULL, 10);
			else {
				wanted_bus = strtoul(argv[i], NULL, 10);
				wanted_dev = strtoul(colon + 1, NULL, 10);
			}
		} 
		else if (strcmp(argv[i], "-d") == 0) {
			char *colon;
			i++;
			if (i >= argc)
				die("missing argument");
			wanted_vendor = strtoul(argv[i], NULL, 16);
			if (colon)
				wanted_product = strtoul(colon + 1, NULL, 16);
		}
		else if (strcmp(argv[i], "-l") == 0) {
			op = DEBUG_LIST;
		}
		else if (strcmp(argv[i], "-r") == 0) {
			op = DEBUG_READ;
		}
		else if (strcmp(argv[i], "-w") == 0) {
			op = DEBUG_WRITE;
		}
		else if (strcmp(argv[i], "-rw") == 0) {
			op = DEBUG_REDIR;
		}
		else {
			die("Unknown argument: %s\n", argv[i]);
		}
#if 0
		if (strcmp(argv[i], "-d") == 0)
			break;
#endif
	}

	
	usb_init();
	usb_find_busses();
	usb_find_devices();
	
	dev = next_debug_device(NULL, &debug_desc);
	for (; dev; dev = next_debug_device(dev, &debug_desc)) {
		int busnum;
		busnum = strtol(dev->bus->dirname, NULL, 10);
		if ((wanted_bus != -1) && (busnum != wanted_bus))
			continue;
		if ((wanted_dev != -1) && (dev->devnum != wanted_dev))
			continue;
		if ((wanted_vendor != -1) && 
		    (dev->descriptor.idVendor != wanted_vendor))
			continue;
		if ((wanted_product != -1) && 
		    (dev->descriptor.idProduct != wanted_product))
			continue;
		if (op != DEBUG_LIST)
			goto found;
		printf("%d.%d %04x:%04x\n",
			busnum, dev->devnum,
			dev->descriptor.idVendor,
			dev->descriptor.idProduct);
	}
	if (op == DEBUG_LIST)
		return 0;
	die("No debug devices found\n");
found:	
	printf("Found one!\n");
	printf("desc: %02x %02x %02x %02x\n",
		debug_desc.bLength,
		debug_desc.bDescriptorType,
		debug_desc.bDebugInEndpoint,
		debug_desc.bDebugOutEndpoint);


	switch(op) {
	case DEBUG_READ:
		usb_debug_read(dev, &debug_desc);
		break;
	case DEBUG_WRITE:
		usb_debug_write(dev, &debug_desc);
		break;
	default:
		die("Unknown operation\n");
	}
	return 0;
}