Adding upstream version 20200122.upstream/20200122

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 793 insertions, 0 deletions

diff --git a/carl9170fw/tools/carlu/src/usb.c b/carl9170fw/tools/carlu/src/usb.c
new file mode 100644
index 0000000..ebc19a9
--- /dev/null
+++ b/carl9170fw/tools/carlu/src/usb.c
@@ -0,0 +1,793 @@
+/*
+ * carlu - userspace testing utility for ar9170 devices
+ *
+ * USB back-end driver
+ *
+ * Copyright 2009-2011 Christian Lamparter <chunkeey@googlemail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <stdlib.h>
+#include "libusb.h"
+
+#include "carlu.h"
+#include "usb.h"
+#include "debug.h"
+#include "list.h"
+#include "cmd.h"
+
+#define ADD_DEV(_vid, _pid, _vs, _ps)	{		\
+	.idVendor = _vid,				\
+	.idProduct = _pid,				\
+	.vendor_name = _vs,				\
+	.product_name = _ps				\
+}
+
+static const struct {
+	uint16_t idVendor;
+	uint16_t idProduct;
+	char *vendor_name;
+	char *product_name;
+} dev_list[] = {
+	ADD_DEV(0x0cf3, 0x9170, "Atheros", "9170"),
+	ADD_DEV(0x0cf3, 0x1001, "Atheros", "TG121N"),
+	ADD_DEV(0x0cf3, 0x1002, "TP-Link", "TL-WN821N v2"),
+	ADD_DEV(0xcace, 0x0300, "Cace", "Airpcap NX"),
+	ADD_DEV(0x07d1, 0x3c10, "D-Link", "DWA 160 A1"),
+	ADD_DEV(0x07d1, 0x3a09, "D-Link", "DWA 160 A2"),
+	ADD_DEV(0x0846, 0x9010, "Netgear", "WNDA3100"),
+	ADD_DEV(0x0846, 0x9001, "Netgear", "WN111 v2"),
+	ADD_DEV(0x0ace, 0x1221, "Zydas", "ZD1221"),
+	ADD_DEV(0x0586, 0x3417, "ZyXEL", "NWD271N"),
+	ADD_DEV(0x0cde, 0x0023, "Z-Com", "UB81 BG"),
+	ADD_DEV(0x0cde, 0x0026, "Z-Com", "UB82 ABG"),
+	ADD_DEV(0x0cde, 0x0027, "Sphairon", "Homelink 1202"),
+	ADD_DEV(0x083a, 0xf522, "Arcadyan", "WN7512"),
+	ADD_DEV(0x2019, 0x5304, "Planex", "GWUS300"),
+	ADD_DEV(0x04bb, 0x093f, "IO-Data", "WNGDNUS2"),
+	ADD_DEV(0x057C, 0x8401, "AVM", "FRITZ!WLAN USB Stick N"),
+	ADD_DEV(0x057C, 0x8402, "AVM", "FRITZ!WLAN USB Stick N 2.4"),
+};
+
+static libusb_context *usb_ctx;
+static LIST_HEAD(active_dev_list);
+
+static int carlusb_event_thread(void *_ar)
+{
+	struct carlu *ar = (void *)_ar;
+	dbg("event thread active and polling.\n");
+
+	while (!ar->stop_event_polling)
+		libusb_handle_events(ar->ctx);
+
+	dbg("==> event thread desixed.\n");
+	return 0;
+}
+
+static int carlusb_is_ar9170(struct libusb_device_descriptor *desc)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(dev_list); i++) {
+		if ((desc->idVendor == dev_list[i].idVendor) &&
+		    (desc->idProduct == dev_list[i].idProduct)) {
+			dbg("== found device \"%s %s\" [0x%04x:0x%04x]\n",
+				dev_list[i].vendor_name, dev_list[i].product_name,
+				desc->idVendor, desc->idProduct);
+
+			return i;
+		}
+	}
+
+	return -1;
+}
+
+static bool carlusb_is_dev(struct carlu *iter,
+			       struct libusb_device *dev)
+{
+	libusb_device *list_dev;
+
+	if (!iter->dev)
+		return false;
+
+	list_dev = libusb_get_device(iter->dev);
+
+	if (libusb_get_bus_number(list_dev) == libusb_get_bus_number(dev) &&
+	    libusb_get_device_address(list_dev) == libusb_get_device_address(dev))
+		return true;
+
+	return false;
+}
+
+int carlusb_show_devinfo(struct carlu *ar)
+{
+	struct libusb_device_descriptor desc;
+	libusb_device *dev;
+	int err;
+
+	dev = libusb_get_device(ar->dev);
+
+	err = libusb_get_device_descriptor(dev, &desc);
+	if (err)
+		return err;
+
+	info("USB Device Information:\n");
+	info("\tUSB VendorID:%.4x(%s), ProductID:%.4x(%s)\n",
+	     dev_list[ar->idx].idVendor, dev_list[ar->idx].vendor_name,
+	     dev_list[ar->idx].idProduct, dev_list[ar->idx].product_name);
+	info("\tBus:%d Address:%d\n", libusb_get_bus_number(dev),
+	     libusb_get_device_address(dev));
+
+	return 0;
+}
+
+static int carlusb_get_dev(struct carlu *ar, bool reset)
+{
+	struct carlu *iter;
+	libusb_device_handle *dev;
+	libusb_device **list;
+	int ret, err, i, idx = -1;
+
+	ret = libusb_get_device_list(usb_ctx, &list);
+	if (ret < 0) {
+		err("usb device enum failed (%d)\n", ret);
+		return ret;
+	}
+
+	for (i = 0; i < ret; i++) {
+		struct libusb_device_descriptor desc;
+
+		memset(&desc, 0, sizeof(desc));
+		err = libusb_get_device_descriptor(list[i], &desc);
+		if (err != 0)
+			continue;
+
+		idx = carlusb_is_ar9170(&desc);
+		if (idx < 0)
+			continue;
+
+		list_for_each_entry(iter, &active_dev_list, dev_list) {
+			if (carlusb_is_dev(iter, list[i])) {
+				err = -EALREADY;
+				break;
+			}
+		}
+
+		if (err)
+			continue;
+
+		err = libusb_open(list[i], &dev);
+		if (err != 0) {
+			err("failed to open device (%d)\n", err);
+			continue;
+		}
+
+		err = libusb_kernel_driver_active(dev, 0);
+		switch (err) {
+		case 0:
+			break;
+		default:
+			err("failed to aquire exculusive access (%d).\n", err);
+			goto skip;
+		}
+
+		if (reset) {
+			err = libusb_reset_device(dev);
+			if (err != 0) {
+				err("failed to reset device (%d)\n", err);
+				goto skip;
+			}
+		}
+
+		err = libusb_claim_interface(dev, 0);
+		if (err == 0) {
+			dbg(">device is now under our control.\n");
+			break;
+		} else {
+			err("failed to claim device (%d)\n", err);
+			goto skip;
+		}
+
+skip:
+		libusb_close(dev);
+	}
+
+	if (i != ret) {
+		ar->idx = idx;
+		ar->ctx = usb_ctx;
+		ar->dev = dev;
+		list_add_tail(&ar->dev_list, &active_dev_list);
+		ret = 0;
+	} else {
+		ret = -ENODEV;
+	}
+
+	libusb_free_device_list(list, 1);
+	return ret;
+}
+
+static void carlusb_tx_cb(struct carlu *ar,
+			      struct frame *frame)
+{
+	if (ar->tx_cb)
+		ar->tx_cb(ar, frame);
+
+	ar->tx_octets += frame->len;
+
+	carlu_free_frame(ar, frame);
+}
+
+static void carlusb_zap_queues(struct carlu *ar)
+{
+	struct frame *frame;
+
+	BUG_ON(SDL_mutexP(ar->tx_queue_lock) != 0);
+	while (!list_empty(&ar->tx_queue)) {
+		frame = list_first_entry(&ar->tx_queue, struct frame, dcb.list);
+		list_del(&frame->dcb.list);
+		carlusb_tx_cb(ar, frame);
+	}
+	SDL_mutexV(ar->tx_queue_lock);
+}
+
+static void carlusb_free_driver(struct carlu *ar)
+{
+	if (!IS_ERR_OR_NULL(ar)) {
+		if (ar->event_pipe[0] > -1)
+			close(ar->event_pipe[0]);
+
+		if (ar->event_pipe[1] > -1)
+			close(ar->event_pipe[1]);
+
+		carlusb_zap_queues(ar);
+		carlfw_release(ar->fw);
+		ar->fw = NULL;
+
+		if (ar->dev) {
+			libusb_release_interface(ar->dev, 0);
+			libusb_close(ar->dev);
+			ar->dev = NULL;
+		}
+		carlu_free_driver(ar);
+	}
+}
+
+static int carlusb_init(struct carlu *ar)
+{
+	init_list_head(&ar->tx_queue);
+	ar->tx_queue_lock = SDL_CreateMutex();
+	ar->event_pipe[0] = ar->event_pipe[1] = -1;
+
+	return 0;
+}
+
+static struct carlu *carlusb_open(void)
+{
+	struct carlu *tmp;
+	int err;
+
+	tmp = carlu_alloc_driver(sizeof(*tmp));
+	if (tmp == NULL)
+		return NULL;
+
+	err = carlusb_init(tmp);
+	if (err < 0)
+		goto err_out;
+
+	err = carlusb_get_dev(tmp, true);
+	if (err < 0)
+		goto err_out;
+
+	return tmp;
+
+err_out:
+	carlusb_free_driver(tmp);
+	return ERR_PTR(err);
+}
+
+static void carlusb_cancel_rings(struct carlu *ar)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(ar->rx_ring); i++)
+		libusb_cancel_transfer(ar->rx_ring[i]);
+
+	libusb_cancel_transfer(ar->rx_interrupt);
+}
+
+static void carlusb_free_rings(struct carlu *ar)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(ar->rx_ring); i++)
+		libusb_free_transfer(ar->rx_ring[i]);
+
+	libusb_free_transfer(ar->rx_interrupt);
+}
+
+static void carlusb_destroy(struct carlu *ar)
+{
+	int event_thread_status;
+
+	dbg("==>release device.\n");
+
+	ar->stop_event_polling = true;
+
+	carlusb_cancel_rings(ar);
+
+	SDL_WaitThread(ar->event_thread, &event_thread_status);
+
+	carlusb_free_rings(ar);
+	list_del(&ar->dev_list);
+}
+
+static void carlusb_tx_bulk_cb(struct libusb_transfer *transfer);
+
+static void carlusb_tx_pending(struct carlu *ar)
+{
+	struct frame *frame;
+	struct libusb_transfer *urb;
+	int err;
+
+	BUG_ON(SDL_mutexP(ar->tx_queue_lock) != 0);
+	if (ar->tx_queue_len >= (AR9170_TX_MAX_ACTIVE_URBS) ||
+	    list_empty(&ar->tx_queue))
+		goto out;
+
+	ar->tx_queue_len++;
+
+	urb = libusb_alloc_transfer(0);
+	if (urb == NULL)
+		goto out;
+
+	frame = list_first_entry(&ar->tx_queue, struct frame, dcb.list);
+	list_del(&frame->dcb.list);
+
+	if (ar->tx_stream) {
+		struct ar9170_stream *tx_stream;
+
+		tx_stream = frame_push(frame, sizeof(*tx_stream));
+		tx_stream->length = cpu_to_le16(frame->len);
+		tx_stream->tag = cpu_to_le16(0x697e);
+	}
+
+	libusb_fill_bulk_transfer(urb, ar->dev, AR9170_EP_TX, (unsigned char *)
+		frame->data, frame->len, carlusb_tx_bulk_cb, (void *)frame, 0);
+
+	/* FIXME: ZERO_PACKET support! */
+	urb->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
+/*	urb->flags |= LIBUSB_TRANSFER_ZERO_PACKET; */
+	frame->dev = (void *) ar;
+	frame_get(frame);
+
+	err = libusb_submit_transfer(urb);
+	if (err != 0) {
+		err("->usb bulk tx submit failed (%d).\n", err);
+		libusb_free_transfer(urb);
+	}
+
+out:
+	SDL_mutexV(ar->tx_queue_lock);
+	return;
+}
+
+void carlusb_tx(struct carlu *ar, struct frame *frame)
+{
+	BUG_ON(SDL_mutexP(ar->tx_queue_lock) != 0);
+
+	list_add_tail(&frame->dcb.list, &ar->tx_queue);
+	SDL_mutexV(ar->tx_queue_lock);
+
+	carlusb_tx_pending(ar);
+}
+
+static void carlusb_tx_bulk_cb(struct libusb_transfer *transfer)
+{
+	struct frame *frame = (void *) transfer->user_data;
+	struct carlu *ar = (void *) frame->dev;
+
+	BUG_ON(SDL_mutexP(ar->tx_queue_lock) != 0);
+	ar->tx_queue_len--;
+	SDL_mutexV(ar->tx_queue_lock);
+
+	if (ar->tx_stream)
+		frame_pull(frame, 4);
+
+	carlusb_tx_cb(ar, frame);
+	carlusb_tx_pending(ar);
+}
+
+static void carlusb_rx_interrupt_cb(struct libusb_transfer *transfer)
+{
+	struct carlu *ar = (void *) transfer->user_data;
+	int err;
+
+	switch (transfer->status) {
+	case LIBUSB_TRANSFER_COMPLETED:
+		carlu_handle_command(ar, transfer->buffer, transfer->actual_length);
+		break;
+
+	case LIBUSB_TRANSFER_CANCELLED:
+		return;
+
+	default:
+		err("==>rx_irq urb died (%d)\n", transfer->status);
+		break;
+	}
+
+	err = libusb_submit_transfer(transfer);
+	if (err != 0)
+		err("==>rx_irq urb resubmit failed (%d)\n", err);
+}
+
+static void carlusb_rx_bulk_cb(struct libusb_transfer *transfer)
+{
+	struct frame *frame = (void *) transfer->user_data;
+	struct carlu *ar = (void *) frame->dev;
+	int err;
+
+	switch (transfer->status) {
+	case LIBUSB_TRANSFER_COMPLETED:
+		frame_put(frame, transfer->actual_length);
+
+		carlu_rx(ar, frame);
+
+		frame_trim(frame, 0);
+		break;
+
+	case LIBUSB_TRANSFER_CANCELLED:
+		return;
+
+	default:
+		err("==>rx_bulk urb died (%d)\n", transfer->status);
+		break;
+	}
+
+	err = libusb_submit_transfer(transfer);
+	if (err != 0)
+		err("->rx_bulk urb resubmit failed (%d)\n", err);
+}
+
+static int carlusb_initialize_rxirq(struct carlu *ar)
+{
+	int err;
+
+	ar->rx_interrupt = libusb_alloc_transfer(0);
+	if (ar->rx_interrupt == NULL) {
+		err("==>cannot alloc rx interrupt urb\n");
+		return -1;
+	}
+
+	libusb_fill_interrupt_transfer(ar->rx_interrupt, ar->dev, AR9170_EP_IRQ,
+				       (unsigned char *)&ar->irq_buf, sizeof(ar->irq_buf),
+				       carlusb_rx_interrupt_cb, (void *) ar, 0);
+
+	err = libusb_submit_transfer(ar->rx_interrupt);
+	if (err != 0) {
+		err("==>failed to submit rx interrupt (%d)\n", err);
+		return err;
+	}
+
+	dbg("rx interrupt is now operational.\n");
+	return 0;
+}
+
+static int carlusb_initialize_rxrings(struct carlu *ar)
+{
+	struct frame *tmp;
+	unsigned int i;
+	int err;
+
+	for (i = 0; i < ARRAY_SIZE(ar->rx_ring); i++) {
+		tmp = frame_alloc(ar->rx_max);
+		if (tmp == NULL)
+			return -ENOMEM;
+
+		tmp->dev = (void *) ar;
+
+		ar->rx_ring[i] = libusb_alloc_transfer(0);
+		if (ar->rx_ring[i] == NULL) {
+			frame_free(tmp);
+			return -ENOMEM;
+		}
+
+		libusb_fill_bulk_transfer(ar->rx_ring[i], ar->dev,
+			AR9170_EP_RX, (unsigned char *)tmp->data,
+			ar->rx_max, carlusb_rx_bulk_cb, (void *)tmp, 0);
+
+		err = libusb_submit_transfer(ar->rx_ring[i]);
+		if (err != 0) {
+			err("==>failed to submit rx buld urb (%d)\n", err);
+			return EXIT_FAILURE;
+		}
+	}
+
+	dbg("rx ring is now ready to receive.\n");
+	return 0;
+}
+
+static int carlusb_load_firmware(struct carlu *ar)
+{
+	int ret = 0;
+
+	dbg("loading firmware...\n");
+
+	ar->fw = carlfw_load(CARL9170_FIRMWARE_FILE);
+	if (IS_ERR_OR_NULL(ar->fw))
+		return PTR_ERR(ar->fw);
+
+	ret = carlu_fw_check(ar);
+	if (ret)
+		return ret;
+
+	ret = carlusb_fw_check(ar);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int carlusb_upload_firmware(struct carlu *ar, bool boot)
+{
+	uint32_t addr = 0x200000;
+	size_t len;
+	void *buf;
+	int ret = 0;
+
+	dbg("initiating firmware image upload procedure.\n");
+
+	buf = carlfw_get_fw(ar->fw, &len);
+	if (IS_ERR_OR_NULL(buf))
+		return PTR_ERR(buf);
+
+	if (ar->miniboot_size) {
+		dbg("Miniboot firmware size:%d\n", ar->miniboot_size);
+		len -= ar->miniboot_size;
+		buf += ar->miniboot_size;
+	}
+
+	while (len) {
+		int blocklen = len > 4096 ? 4096 : len;
+
+		ret = libusb_control_transfer(ar->dev, 0x40, 0x30, addr >> 8, 0, buf, blocklen, 1000);
+		if (ret != blocklen && ret != LIBUSB_ERROR_TIMEOUT) {
+			err("==>firmware upload failed (%d)\n", ret);
+			return -EXIT_FAILURE;
+		}
+
+		dbg("uploaded %d bytes to start address 0x%04x.\n", blocklen, addr);
+
+		buf += blocklen;
+		addr += blocklen;
+		len -= blocklen;
+	}
+
+	if (boot) {
+		ret = libusb_control_transfer(ar->dev, 0x40, 0x31, 0, 0, NULL, 0, 5000);
+		if (ret < 0) {
+			err("unable to boot firmware (%d)\n", ret);
+			return -EXIT_FAILURE;
+		}
+
+		/* give the firmware some time to reset & reboot */
+		SDL_Delay(100);
+
+		/*
+		 * since the device did a full usb reset,
+		 * we have to get a new "dev".
+		 */
+		libusb_release_interface(ar->dev, 0);
+		libusb_close(ar->dev);
+		ar->dev = NULL;
+		list_del(&ar->dev_list);
+
+		ret = carlusb_get_dev(ar, false);
+	}
+
+	return 0;
+}
+
+int carlusb_cmd_async(struct carlu *ar, struct carl9170_cmd *cmd,
+		      const bool free_buf)
+{
+	struct libusb_transfer *urb;
+	int ret, send;
+
+	if (cmd->hdr.len > (CARL9170_MAX_CMD_LEN - 4)) {
+		err("|-> too much payload\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (cmd->hdr.len % 4) {
+		err("|-> invalid command length\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = libusb_interrupt_transfer(ar->dev, AR9170_EP_CMD, (void *) cmd, cmd->hdr.len + 4, &send, 32);
+	if (ret != 0) {
+		err("OID:0x%.2x failed due to (%d) (%d).\n", cmd->hdr.cmd, ret, send);
+		print_hex_dump_bytes(ERROR, "CMD:", cmd, cmd->hdr.len);
+	}
+
+out:
+	if (free_buf)
+		free((void *)cmd);
+
+	return ret;
+}
+
+int carlusb_cmd(struct carlu *ar, uint8_t oid,
+		      uint8_t *cmd, size_t clen,
+		      uint8_t *rsp, size_t rlen)
+{
+	int ret, send;
+
+	if (clen > (CARL9170_MAX_CMD_LEN - 4)) {
+		err("|-> OID:0x%.2x has too much payload (%d octs)\n", oid, (int)clen);
+		return -EINVAL;
+	}
+
+	ret = SDL_mutexP(ar->resp_lock);
+	if (ret != 0) {
+		err("failed to acquire resp_lock.\n");
+		print_hex_dump_bytes(ERROR, "CMD:", ar->cmd.buf, clen);
+		return -1;
+	}
+
+	ar->cmd.cmd.hdr.len = clen;
+	ar->cmd.cmd.hdr.cmd = oid;
+	/* buf[2] & buf[3] are padding */
+	if (clen && cmd != (uint8_t *)(&ar->cmd.cmd.data))
+		memcpy(&ar->cmd.cmd.data, cmd, clen);
+
+	ar->resp_buf = (uint8_t *)rsp;
+	ar->resp_len = rlen;
+
+	ret = carlusb_cmd_async(ar, &ar->cmd.cmd, false);
+	if (ret != 0) {
+		err("OID:0x%.2x failed due to (%d) (%d).\n", oid, ret, send);
+		print_hex_dump_bytes(ERROR, "CMD:", ar->cmd.buf, clen);
+		SDL_mutexV(ar->resp_lock);
+		return ret;
+	}
+
+	ret = SDL_CondWaitTimeout(ar->resp_pend, ar->resp_lock, 100);
+	if (ret != 0) {
+		err("|-> OID:0x%.2x timed out %d.\n", oid, ret);
+		ar->resp_buf = NULL;
+		ar->resp_len = 0;
+		ret = -ETIMEDOUT;
+	}
+
+	SDL_mutexV(ar->resp_lock);
+	return ret;
+}
+
+struct carlu *carlusb_probe(void)
+{
+	struct carlu *ar;
+	int ret = -ENOMEM;
+
+	ar = carlusb_open();
+	if (IS_ERR_OR_NULL(ar)) {
+		if (IS_ERR(ar))
+			ret = PTR_ERR(ar);
+		goto err_out;
+	}
+
+	ret = carlusb_show_devinfo(ar);
+	if (ret)
+		goto err_out;
+
+	ret = carlusb_load_firmware(ar);
+	if (ret)
+		goto err_out;
+
+	ret = pipe(ar->event_pipe);
+	if (ret)
+		goto err_out;
+
+	ar->stop_event_polling = false;
+	ar->event_thread = SDL_CreateThread(carlusb_event_thread, ar);
+
+	ret = carlusb_upload_firmware(ar, true);
+	if (ret)
+		goto err_kill;
+
+	ret = carlusb_initialize_rxirq(ar);
+	if (ret)
+		goto err_kill;
+
+	ret = carlusb_initialize_rxrings(ar);
+	if (ret)
+		goto err_kill;
+
+	ret = carlu_cmd_echo(ar, 0x44110dee);
+	if (ret) {
+		err("echo test failed...\n");
+		goto err_kill;
+	}
+
+	info("firmware is active and running.\n");
+
+	carlu_fw_info(ar);
+
+	return ar;
+
+err_kill:
+	carlusb_destroy(ar);
+
+err_out:
+	carlusb_free_driver(ar);
+	err("usb device rendezvous failed (%d).\n", ret);
+	return ERR_PTR(ret);
+}
+
+void carlusb_close(struct carlu *ar)
+{
+	carlu_cmd_reboot(ar);
+
+	carlusb_destroy(ar);
+	carlusb_free_driver(ar);
+}
+
+int carlusb_print_known_devices(void)
+{
+	unsigned int i;
+
+	debug_level = INFO;
+
+	info("==> dumping known device list <==\n");
+	for (i = 0; i < ARRAY_SIZE(dev_list); i++) {
+		info("Vendor:\"%-9s\" Product:\"%-26s\" => USBID:[0x%04x:0x%04x]\n",
+		     dev_list[i].vendor_name, dev_list[i].product_name,
+		     dev_list[i].idVendor, dev_list[i].idProduct);
+	}
+	info("==> end of device list <==\n");
+
+	return EXIT_SUCCESS;
+}
+
+int usb_init(void)
+{
+	int ret;
+
+	ret = libusb_init(&usb_ctx);
+	if (ret != 0) {
+		err("failed to initialize usb subsystem (%d)\n", ret);
+		return ret;
+	}
+
+	/* like a silent chatterbox! */
+	libusb_set_debug(usb_ctx, 2);
+
+	return 0;
+}
+
+void usb_exit(void)
+{
+	libusb_exit(usb_ctx);
+}