/*
* Core functions for libusb-compat-0.1
* Copyright (C) 2008 Daniel Drake <dsd@gentoo.org>
* Copyright (c) 2000-2003 Johannes Erdfelt <johannes@erdfelt.com>
*
* 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 <config.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <libusb.h>
#include "usb.h"
#include "usbi.h"
static libusb_context *ctx = NULL;
static int usb_debug = 0;
enum usbi_log_level {
LOG_LEVEL_DEBUG,
LOG_LEVEL_INFO,
LOG_LEVEL_WARNING,
LOG_LEVEL_ERROR,
};
#ifdef ENABLE_LOGGING
#define _usbi_log(level, fmt...) usbi_log(level, __FUNCTION__, fmt)
#else
#define _usbi_log(level, fmt...)
#endif
#ifdef ENABLE_DEBUG_LOGGING
#define usbi_dbg(fmt...) _usbi_log(LOG_LEVEL_DEBUG, fmt)
#else
#define usbi_dbg(fmt...)
#endif
#define usbi_info(fmt...) _usbi_log(LOG_LEVEL_INFO, fmt)
#define usbi_warn(fmt...) _usbi_log(LOG_LEVEL_WARNING, fmt)
#define usbi_err(fmt...) _usbi_log(LOG_LEVEL_ERROR, fmt)
API_EXPORTED struct usb_bus *usb_busses = NULL;
#define compat_err(e) -(errno=libusb_to_errno(e))
static int libusb_to_errno(int result)
{
switch (result) {
case LIBUSB_SUCCESS:
return 0;
case LIBUSB_ERROR_IO:
return EIO;
case LIBUSB_ERROR_INVALID_PARAM:
return EINVAL;
case LIBUSB_ERROR_ACCESS:
return EACCES;
case LIBUSB_ERROR_NO_DEVICE:
return ENXIO;
case LIBUSB_ERROR_NOT_FOUND:
return ENOENT;
case LIBUSB_ERROR_BUSY:
return EBUSY;
case LIBUSB_ERROR_TIMEOUT:
return ETIMEDOUT;
case LIBUSB_ERROR_OVERFLOW:
return EOVERFLOW;
case LIBUSB_ERROR_PIPE:
return EPIPE;
case LIBUSB_ERROR_INTERRUPTED:
return EINTR;
case LIBUSB_ERROR_NO_MEM:
return ENOMEM;
case LIBUSB_ERROR_NOT_SUPPORTED:
return ENOSYS;
default:
return ERANGE;
}
}
static void usbi_log(enum usbi_log_level level, const char *function,
const char *format, ...)
{
va_list args;
FILE *stream = stdout;
const char *prefix;
#ifndef ENABLE_DEBUG_LOGGING
if (!usb_debug)
return;
#endif
switch (level) {
case LOG_LEVEL_INFO:
prefix = "info";
break;
case LOG_LEVEL_WARNING:
stream = stderr;
prefix = "warning";
break;
case LOG_LEVEL_ERROR:
stream = stderr;
prefix = "error";
break;
case LOG_LEVEL_DEBUG:
stream = stderr;
prefix = "debug";
break;
default:
stream = stderr;
prefix = "unknown";
break;
}
fprintf(stream, "libusb-compat %s: %s: ", prefix, function);
va_start (args, format);
vfprintf(stream, format, args);
va_end (args);
fprintf(stream, "\n");
}
API_EXPORTED void usb_init(void)
{
int r;
usbi_dbg("");
if (!ctx) {
r = libusb_init(&ctx);
if (r < 0) {
usbi_err("initialization failed!");
return;
}
/* usb_set_debug can be called before usb_init */
if (usb_debug)
libusb_set_debug(ctx, 3);
}
}
API_EXPORTED void usb_set_debug(int level)
{
usb_debug = level;
/* usb_set_debug can be called before usb_init */
if (ctx)
libusb_set_debug(ctx, 3);
}
API_EXPORTED char *usb_strerror(void)
{
return strerror(errno);
}
static int find_busses(struct usb_bus **ret)
{
libusb_device **dev_list = NULL;
struct usb_bus *busses = NULL;
struct usb_bus *bus;
int dev_list_len = 0;
int i;
int r;
r = libusb_get_device_list(ctx, &dev_list);
if (r < 0) {
usbi_err("get_device_list failed with error %d", r);
return compat_err(r);
}
if (r == 0) {
libusb_free_device_list(dev_list, 1);
/* no buses */
return 0;
}
/* iterate over the device list, identifying the individual busses.
* we use the location field of the usb_bus structure to store the
* bus number. */
dev_list_len = r;
for (i = 0; i < dev_list_len; i++) {
libusb_device *dev = dev_list[i];
uint8_t bus_num = libusb_get_bus_number(dev);
/* if we already know about it, continue */
if (busses) {
bus = busses;
int found = 0;
do {
if (bus_num == bus->location) {
found = 1;
break;
}
} while ((bus = bus->next) != NULL);
if (found)
continue;
}
/* add it to the list of busses */
bus = malloc(sizeof(*bus));
if (!bus)
goto err;
memset(bus, 0, sizeof(*bus));
bus->location = bus_num;
sprintf(bus->dirname, "%03d", bus_num);
LIST_ADD(busses, bus);
}
libusb_free_device_list(dev_list, 1);
*ret = busses;
return 0;
err:
bus = busses;
while (bus) {
struct usb_bus *tbus = bus->next;
free(bus);
bus = tbus;
}
return -ENOMEM;
}
API_EXPORTED int usb_find_busses(void)
{
struct usb_bus *new_busses = NULL;
struct usb_bus *bus;
int changes = 0;
int r;
/* libusb-1.0 initialization might have failed, but we can't indicate
* this with libusb-0.1, so trap that situation here */
if (!ctx)
return 0;
usbi_dbg("");
r = find_busses(&new_busses);
if (r < 0) {
usbi_err("find_busses failed with error %d", r);
return r;
}
/* walk through all busses we already know about, removing duplicates
* from the new list. if we do not find it in the new list, the bus
* has been removed. */
bus = usb_busses;
while (bus) {
struct usb_bus *tbus = bus->next;
struct usb_bus *nbus = new_busses;
int found = 0;
usbi_dbg("in loop");
#if 0 /* (yavor) NO caching */
while (nbus) {
struct usb_bus *tnbus = nbus->next;
if (bus->location == nbus->location) {
LIST_DEL(new_busses, nbus);
free(nbus);
found = 1;
break;
}
nbus = tnbus;
}
#endif
if (!found) {
/* bus removed */
usbi_dbg("bus %d removed", bus->location);
changes++;
LIST_DEL(usb_busses, bus);
free(bus);
}
bus = tbus;
}
/* anything remaining in new_busses is a new bus */
bus = new_busses;
while (bus) {
struct usb_bus *tbus = bus->next;
usbi_dbg("bus %d added", bus->location);
LIST_DEL(new_busses, bus);
LIST_ADD(usb_busses, bus);
changes++;
bus = tbus;
}
return changes;
}
static int find_devices(libusb_device **dev_list, int dev_list_len,
struct usb_bus *bus, struct usb_device **ret)
{
struct usb_device *devices = NULL;
struct usb_device *dev;
int i;
for (i = 0; i < dev_list_len; i++) {
libusb_device *newlib_dev = dev_list[i];
uint8_t bus_num = libusb_get_bus_number(newlib_dev);
if (bus_num != bus->location)
continue;
dev = malloc(sizeof(*dev));
if (!dev)
goto err;
/* No need to reference the device now, just take the pointer. We
* increase the reference count later if we keep the device. */
dev->dev = newlib_dev;
dev->bus = bus;
dev->devnum = libusb_get_device_address(newlib_dev);
sprintf(dev->filename, "%03d", dev->devnum);
LIST_ADD(devices, dev);
}
*ret = devices;
return 0;
err:
dev = devices;
while (dev) {
struct usb_device *tdev = dev->next;
free(dev);
dev = tdev;
}
return -ENOMEM;
}
static void clear_endpoint_descriptor(struct usb_endpoint_descriptor *ep)
{
if (ep->extra)
free(ep->extra);
}
static void clear_interface_descriptor(struct usb_interface_descriptor *iface)
{
if (iface->extra)
free(iface->extra);
if (iface->endpoint) {
int i;
for (i = 0; i < iface->bNumEndpoints; i++)
clear_endpoint_descriptor(iface->endpoint + i);
free(iface->endpoint);
}
}
static void clear_interface(struct usb_interface *iface)
{
if (iface->altsetting) {
int i;
for (i = 0; i < iface->num_altsetting; i++)
clear_interface_descriptor(iface->altsetting + i);
free(iface->altsetting);
}
}
static void clear_config_descriptor(struct usb_config_descriptor *config)
{
if (config->extra)
free(config->extra);
if (config->interface) {
int i;
for (i = 0; i < config->bNumInterfaces; i++)
clear_interface(config->interface + i);
free(config->interface);
}
}
static void clear_device(struct usb_device *dev)
{
int i;
for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
clear_config_descriptor(dev->config + i);
}
static int copy_endpoint_descriptor(struct usb_endpoint_descriptor *dest,
const struct libusb_endpoint_descriptor *src)
{
memcpy(dest, src, USB_DT_ENDPOINT_AUDIO_SIZE);
dest->extralen = src->extra_length;
if (src->extra_length) {
dest->extra = malloc(src->extra_length);
if (!dest->extra)
return -ENOMEM;
memcpy(dest->extra, src->extra, src->extra_length);
}
return 0;
}
static int copy_interface_descriptor(struct usb_interface_descriptor *dest,
const struct libusb_interface_descriptor *src)
{
int i;
int num_endpoints = src->bNumEndpoints;
size_t alloc_size = sizeof(struct usb_endpoint_descriptor) * num_endpoints;
memcpy(dest, src, USB_DT_INTERFACE_SIZE);
dest->endpoint = malloc(alloc_size);
if (!dest->endpoint)
return -ENOMEM;
memset(dest->endpoint, 0, alloc_size);
for (i = 0; i < num_endpoints; i++) {
int r = copy_endpoint_descriptor(dest->endpoint + i, &src->endpoint[i]);
if (r < 0) {
clear_interface_descriptor(dest);
return r;
}
}
dest->extralen = src->extra_length;
if (src->extra_length) {
dest->extra = malloc(src->extra_length);
if (!dest->extra) {
clear_interface_descriptor(dest);
return -ENOMEM;
}
memcpy(dest->extra, src->extra, src->extra_length);
}
return 0;
}
static int copy_interface(struct usb_interface *dest,
const struct libusb_interface *src)
{
int i;
int num_altsetting = src->num_altsetting;
size_t alloc_size = sizeof(struct usb_interface_descriptor)
* num_altsetting;
dest->num_altsetting = num_altsetting;
dest->altsetting = malloc(alloc_size);
if (!dest->altsetting)
return -ENOMEM;
memset(dest->altsetting, 0, alloc_size);
for (i = 0; i < num_altsetting; i++) {
int r = copy_interface_descriptor(dest->altsetting + i,
&src->altsetting[i]);
if (r < 0) {
clear_interface(dest);
return r;
}
}
return 0;
}
static int copy_config_descriptor(struct usb_config_descriptor *dest,
const struct libusb_config_descriptor *src)
{
int i;
int num_interfaces = src->bNumInterfaces;
size_t alloc_size = sizeof(struct usb_interface) * num_interfaces;
memcpy(dest, src, USB_DT_CONFIG_SIZE);
dest->interface = malloc(alloc_size);
if (!dest->interface)
return -ENOMEM;
memset(dest->interface, 0, alloc_size);
for (i = 0; i < num_interfaces; i++) {
int r = copy_interface(dest->interface + i, &src->interface[i]);
if (r < 0) {
clear_config_descriptor(dest);
return r;
}
}
dest->extralen = src->extra_length;
if (src->extra_length) {
dest->extra = malloc(src->extra_length);
if (!dest->extra) {
clear_config_descriptor(dest);
return -ENOMEM;
}
memcpy(dest->extra, src->extra, src->extra_length);
}
return 0;
}
static int initialize_device(struct usb_device *dev)
{
libusb_device *newlib_dev = dev->dev;
int num_configurations;
size_t alloc_size;
int r;
int i;
/* device descriptor is identical in both libs */
r = libusb_get_device_descriptor(newlib_dev,
(struct libusb_device_descriptor *) &dev->descriptor);
if (r < 0) {
usbi_err("error %d getting device descriptor", r);
return compat_err(r);
}
num_configurations = dev->descriptor.bNumConfigurations;
alloc_size = sizeof(struct usb_config_descriptor) * num_configurations;
dev->config = malloc(alloc_size);
if (!dev->config)
return -ENOMEM;
memset(dev->config, 0, alloc_size);
/* even though structures are identical, we can't just use libusb-1.0's
* config descriptors because we have to store all configurations in
* a single flat memory area (libusb-1.0 provides separate allocations).
* we hand-copy libusb-1.0's descriptors into our own structures. */
for (i = 0; i < num_configurations; i++) {
struct libusb_config_descriptor *newlib_config;
r = libusb_get_config_descriptor(newlib_dev, i, &newlib_config);
if (r < 0) {
clear_device(dev);
free(dev->config);
return compat_err(r);
}
r = copy_config_descriptor(dev->config + i, newlib_config);
libusb_free_config_descriptor(newlib_config);
if (r < 0) {
clear_device(dev);
free(dev->config);
return r;
}
}
/* libusb doesn't implement this and it doesn't seem that important. If
* someone asks for it, we can implement it in v1.1 or later. */
dev->num_children = 0;
dev->children = NULL;
libusb_ref_device(newlib_dev);
return 0;
}
static void free_device(struct usb_device *dev)
{
clear_device(dev);
libusb_unref_device(dev->dev);
free(dev);
}
API_EXPORTED int usb_find_devices(void)
{
struct usb_bus *bus;
libusb_device **dev_list;
int dev_list_len;
int r;
int changes = 0;
/* libusb-1.0 initialization might have failed, but we can't indicate
* this with libusb-0.1, so trap that situation here */
if (!ctx)
return 0;
usbi_dbg("");
dev_list_len = libusb_get_device_list(ctx, &dev_list);
if (dev_list_len < 0)
return compat_err(dev_list_len);
for (bus = usb_busses; bus; bus = bus->next) {
struct usb_device *new_devices = NULL;
struct usb_device *dev;
r = find_devices(dev_list, dev_list_len, bus, &new_devices);
if (r < 0) {
libusb_free_device_list(dev_list, 1);
return r;
}
/* walk through the devices we already know about, removing duplicates
* from the new list. if we do not find it in the new list, the device
* has been removed. */
dev = bus->devices;
while (dev) {
int found = 0;
struct usb_device *tdev = dev->next;
struct usb_device *ndev = new_devices;
while (ndev) {
if (ndev->devnum == dev->devnum) {
LIST_DEL(new_devices, ndev);
free(ndev);
found = 1;
break;
}
ndev = ndev->next;
}
if (!found) {
usbi_dbg("device %d.%d removed",
dev->bus->location, dev->devnum);
LIST_DEL(bus->devices, dev);
free_device(dev);
changes++;
}
dev = tdev;
}
/* anything left in new_devices is a new device */
dev = new_devices;
while (dev) {
struct usb_device *tdev = dev->next;
r = initialize_device(dev);
if (r < 0) {
usbi_err("couldn't initialize device %d.%d (error %d)",
dev->bus->location, dev->devnum, r);
dev = tdev;
continue;
}
usbi_dbg("device %d.%d added", dev->bus->location, dev->devnum);
LIST_DEL(new_devices, dev);
LIST_ADD(bus->devices, dev);
changes++;
dev = tdev;
}
}
libusb_free_device_list(dev_list, 1);
return changes;
}
API_EXPORTED struct usb_bus *usb_get_busses(void)
{
return usb_busses;
}
API_EXPORTED usb_dev_handle *usb_open(struct usb_device *dev)
{
int r;
usbi_dbg("");
usb_dev_handle *udev = malloc(sizeof(*udev));
if (!udev)
return NULL;
r = libusb_open((libusb_device *) dev->dev, &udev->handle);
if (r < 0) {
usbi_err("could not open device, error %d", r);
free(udev);
errno = libusb_to_errno(r);
return NULL;
}
udev->last_claimed_interface = -1;
udev->device = dev;
return udev;
}
API_EXPORTED int usb_close(usb_dev_handle *dev)
{
usbi_dbg("");
libusb_close(dev->handle);
free(dev);
return 0;
}
API_EXPORTED struct usb_device *usb_device(usb_dev_handle *dev)
{
return dev->device;
}
API_EXPORTED int usb_set_configuration(usb_dev_handle *dev, int configuration)
{
usbi_dbg("configuration %d", configuration);
return compat_err(libusb_set_configuration(dev->handle, configuration));
}
API_EXPORTED int usb_claim_interface(usb_dev_handle *dev, int interface)
{
int r;
usbi_dbg("interface %d", interface);
r = libusb_claim_interface(dev->handle, interface);
if (r == 0) {
dev->last_claimed_interface = interface;
return 0;
}
return compat_err(r);
}
API_EXPORTED int usb_release_interface(usb_dev_handle *dev, int interface)
{
int r;
usbi_dbg("interface %d", interface);
r = libusb_release_interface(dev->handle, interface);
if (r == 0)
dev->last_claimed_interface = -1;
return compat_err(r);
}
API_EXPORTED int usb_set_altinterface(usb_dev_handle *dev, int alternate)
{
usbi_dbg("alternate %d", alternate);
if (dev->last_claimed_interface < 0)
return -(errno=EINVAL);
return compat_err(libusb_set_interface_alt_setting(dev->handle,
dev->last_claimed_interface, alternate));
}
API_EXPORTED int usb_resetep(usb_dev_handle *dev, unsigned int ep)
{
return compat_err(usb_clear_halt(dev, ep));
}
API_EXPORTED int usb_clear_halt(usb_dev_handle *dev, unsigned int ep)
{
usbi_dbg("endpoint %x", ep);
return compat_err(libusb_clear_halt(dev->handle, ep & 0xff));
}
API_EXPORTED int usb_reset(usb_dev_handle *dev)
{
usbi_dbg("");
return compat_err(libusb_reset_device(dev->handle));
}
static int usb_bulk_io(usb_dev_handle *dev, int ep, char *bytes,
int size, int timeout)
{
int actual_length;
int r;
usbi_dbg("endpoint %x size %d timeout %d", ep, size, timeout);
r = libusb_bulk_transfer(dev->handle, ep & 0xff, bytes, size,
&actual_length, timeout);
/* if we timed out but did transfer some data, report as successful short
* read. FIXME: is this how libusb-0.1 works? */
if (r == 0 || (r == LIBUSB_ERROR_TIMEOUT && actual_length > 0))
return actual_length;
return compat_err(r);
}
API_EXPORTED int usb_bulk_read(usb_dev_handle *dev, int ep, char *bytes,
int size, int timeout)
{
if (!(ep & USB_ENDPOINT_IN)) {
/* libusb-0.1 will strangely fix up a read request from endpoint
* 0x01 to be from endpoint 0x81. do the same thing here, but
* warn about this silly behaviour. */
usbi_warn("endpoint %x is missing IN direction bit, fixing");
ep |= USB_ENDPOINT_IN;
}
return usb_bulk_io(dev, ep, bytes, size, timeout);
}
API_EXPORTED int usb_bulk_write(usb_dev_handle *dev, int ep, char *bytes,
int size, int timeout)
{
if (ep & USB_ENDPOINT_IN) {
/* libusb-0.1 on BSD strangely fix up a write request to endpoint
* 0x81 to be to endpoint 0x01. do the same thing here, but
* warn about this silly behaviour. */
usbi_warn("endpoint %x has excessive IN direction bit, fixing");
ep &= ~USB_ENDPOINT_IN;
}
return usb_bulk_io(dev, ep, bytes, size, timeout);
}
static int usb_interrupt_io(usb_dev_handle *dev, int ep, char *bytes,
int size, int timeout)
{
int actual_length;
int r;
usbi_dbg("endpoint %x size %d timeout %d", ep, size, timeout);
r = libusb_interrupt_transfer(dev->handle, ep & 0xff, bytes, size,
&actual_length, timeout);
/* if we timed out but did transfer some data, report as successful short
* read. FIXME: is this how libusb-0.1 works? */
if (r == 0 || (r == LIBUSB_ERROR_TIMEOUT && actual_length > 0))
return actual_length;
return compat_err(r);
}
API_EXPORTED int usb_interrupt_read(usb_dev_handle *dev, int ep, char *bytes,
int size, int timeout)
{
if (!(ep & USB_ENDPOINT_IN)) {
/* libusb-0.1 will strangely fix up a read request from endpoint
* 0x01 to be from endpoint 0x81. do the same thing here, but
* warn about this silly behaviour. */
usbi_warn("endpoint %x is missing IN direction bit, fixing");
ep |= USB_ENDPOINT_IN;
}
return usb_interrupt_io(dev, ep, bytes, size, timeout);
}
API_EXPORTED int usb_interrupt_write(usb_dev_handle *dev, int ep, char *bytes,
int size, int timeout)
{
if (ep & USB_ENDPOINT_IN) {
/* libusb-0.1 on BSD strangely fix up a write request to endpoint
* 0x81 to be to endpoint 0x01. do the same thing here, but
* warn about this silly behaviour. */
usbi_warn("endpoint %x has excessive IN direction bit, fixing");
ep &= ~USB_ENDPOINT_IN;
}
return usb_interrupt_io(dev, ep, bytes, size, timeout);
}
API_EXPORTED int usb_control_msg(usb_dev_handle *dev, int bmRequestType,
int bRequest, int wValue, int wIndex, char *bytes, int size, int timeout)
{
int r;
usbi_dbg("RQT=%x RQ=%x V=%x I=%x len=%d timeout=%d", bmRequestType,
bRequest, wValue, wIndex, size, timeout);
r = libusb_control_transfer(dev->handle, bmRequestType & 0xff,
bRequest & 0xff, wValue & 0xffff, wIndex & 0xffff, bytes, size & 0xffff,
timeout);
if (r >= 0)
return r;
return compat_err(r);
}
API_EXPORTED int usb_get_string(usb_dev_handle *dev, int desc_index, int langid,
char *buf, size_t buflen)
{
int r;
r = libusb_get_string_descriptor(dev->handle, desc_index & 0xff,
langid & 0xffff, buf, (int) buflen);
if (r >= 0)
return r;
return compat_err(r);
}
API_EXPORTED int usb_get_string_simple(usb_dev_handle *dev, int desc_index,
char *buf, size_t buflen)
{
int r;
r = libusb_get_string_descriptor_ascii(dev->handle, desc_index & 0xff,
buf, (int) buflen);
if (r >= 0)
return r;
return compat_err(r);
}
API_EXPORTED int usb_get_descriptor(usb_dev_handle *dev, unsigned char type,
unsigned char desc_index, void *buf, int size)
{
int r;
r = libusb_get_descriptor(dev->handle, type, desc_index, buf, size);
if (r >= 0)
return r;
return compat_err(r);
}
API_EXPORTED int usb_get_descriptor_by_endpoint(usb_dev_handle *dev, int ep,
unsigned char type, unsigned char desc_index, void *buf, int size)
{
/* this function doesn't make much sense - the specs don't talk about
* getting a descriptor "by endpoint". libusb-1.0 does not provide this
* functionality so we just send a control message directly */
int r;
r = libusb_control_transfer(dev->handle,
LIBUSB_ENDPOINT_IN | (ep & 0xff), LIBUSB_REQUEST_GET_DESCRIPTOR,
(type << 8) | desc_index, 0, buf, size, 1000);
if (r >= 0)
return r;
return compat_err(r);
}
API_EXPORTED int usb_get_driver_np(usb_dev_handle *dev, int interface,
char *name, unsigned int namelen)
{
int r = libusb_kernel_driver_active(dev->handle, interface);
if (r == 1) {
/* libusb-1.0 doesn't expose driver name, so fill in a dummy value */
snprintf(name, namelen, "dummy");
return 0;
} else if (r == 0) {
return -(errno=ENODATA);
} else {
return compat_err(r);
}
}
API_EXPORTED int usb_detach_kernel_driver_np(usb_dev_handle *dev, int interface)
{
return compat_err(libusb_detach_kernel_driver(dev->handle, interface));
}