fx2/linux/libstrm/usb2strm.c

/* *****************************************************************************
 * Copyright (c) 2013 Benjamin Krill <benjamin@krll.de>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 * ****************************************************************************/
#include <stdlib.h>
#include <stdio.h>
#include <usb.h>
#include <string.h>
#include <endian.h>
#include <strm.h>

#define DEBUG 0

#if defined(DEBUG) && DEBUG == 1
	#define printf_dbg(fmt, args...) printf(fmt, ## args)
#else
	#define printf_dbg(args...)
#endif

static usb_dev_handle *hd = NULL;

/* TODO: extend to support multiple USB device on one host! */
static struct usb_device *
find_device(struct usb_bus* busses, int vendor, int product)
{
	struct usb_bus *bus;
	struct usb_device *dev;

	for (bus = busses; bus; bus = bus->next) {
		printf_dbg("scanning bus %s\n", bus->dirname);

		for (dev = bus->devices; dev; dev=dev->next) {
			/* compare device vendor and product */
			if ((dev->descriptor.idVendor == vendor) &&
			    (dev->descriptor.idProduct == product))	{
				/* print device information */
				printf_dbg("\tfound device %s bus %s (idVendor 0x%04x idProduct 0x%04x)\n",
				            dev->filename, dev->bus->dirname, dev->descriptor.idVendor,
				            dev->descriptor.idProduct);
				return dev;
			} else {
				printf_dbg("\tdevice %s does not match\n", dev->filename);
			}
		}
	}
	return NULL;
}

usb_dev_handle *
strm_init(int vendor, int product)
{
	struct usb_device *dev;

	usb_init();
	usb_find_busses();
	usb_find_devices();
	if ((dev = find_device(usb_get_busses(), vendor, product)) == NULL)
		return NULL;

	if (!(hd = usb_open(dev))) {
		printf("FAILED: cannot open device.\n");
		return NULL;
	}
	/* reset usb device */
	usb_reset(hd);
	printf_dbg("Lets do the magic (%p) ...\n", hd);

	return hd;
}

int
strm_fini(void)
{
	if (hd)
		usb_close(hd);
	hd = NULL;
	return 0;
}