2 * Public libusb header file
3 * Copyright © 2001 Johannes Erdfelt <johannes@erdfelt.com>
4 * Copyright © 2007-2008 Daniel Drake <dsd@gentoo.org>
5 * Copyright © 2012 Pete Batard <pete@akeo.ie>
6 * Copyright © 2012 Nathan Hjelm <hjelmn@cs.unm.edu>
7 * For more information, please visit: http://libusb.info
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this library; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 /* on MS environments, the inline keyword is available in C++ only */
29 #if !defined(__cplusplus)
30 #define inline __inline
32 /* ssize_t is also not available (copy/paste from MinGW) */
33 #ifndef _SSIZE_T_DEFINED
34 #define _SSIZE_T_DEFINED
37 typedef __int64 ssize_t;
41 #endif /* _SSIZE_T_DEFINED */
44 /* stdint.h is not available on older MSVC */
45 #if defined(_MSC_VER) && (_MSC_VER < 1600) && (!defined(_STDINT)) && (!defined(_STDINT_H))
46 typedef unsigned __int8 uint8_t;
47 typedef unsigned __int16 uint16_t;
48 typedef unsigned __int32 uint32_t;
53 #if !defined(_WIN32_WCE)
54 #include <sys/types.h>
57 #if defined(__linux) || defined(__APPLE__) || defined(__CYGWIN__) || defined(__HAIKU__)
64 /* 'interface' might be defined as a macro on Windows, so we need to
65 * undefine it so as not to break the current libusb API, because
66 * libusb_config_descriptor has an 'interface' member
67 * As this can be problematic if you include windows.h after libusb.h
68 * in your sources, we force windows.h to be included first. */
69 #if defined(_WIN32) || defined(__CYGWIN__) || defined(_WIN32_WCE)
71 #if defined(interface)
74 #if !defined(__CYGWIN__)
79 #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
80 #define LIBUSB_DEPRECATED_FOR(f) \
81 __attribute__((deprecated("Use " #f " instead")))
83 #define LIBUSB_DEPRECATED_FOR(f)
88 * libusb's Windows calling convention.
90 * Under Windows, the selection of available compilers and configurations
91 * means that, unlike other platforms, there is not <em>one true calling
92 * convention</em> (calling convention: the manner in which parameters are
93 * passed to functions in the generated assembly code).
95 * Matching the Windows API itself, libusb uses the WINAPI convention (which
96 * translates to the <tt>stdcall</tt> convention) and guarantees that the
97 * library is compiled in this way. The public header file also includes
98 * appropriate annotations so that your own software will use the right
99 * convention, even if another convention is being used by default within
102 * The one consideration that you must apply in your software is to mark
103 * all functions which you use as libusb callbacks with this LIBUSB_CALL
104 * annotation, so that they too get compiled for the correct calling
107 * On non-Windows operating systems, this macro is defined as nothing. This
108 * means that you can apply it to your code without worrying about
109 * cross-platform compatibility.
111 /* LIBUSB_CALL must be defined on both definition and declaration of libusb
112 * functions. You'd think that declaration would be enough, but cygwin will
113 * complain about conflicting types unless both are marked this way.
114 * The placement of this macro is important too; it must appear after the
115 * return type, before the function name. See internal documentation for
118 #if defined(_WIN32) || defined(__CYGWIN__) || defined(_WIN32_WCE)
119 #define LIBUSB_CALL WINAPI
124 /** \def LIBUSB_API_VERSION
126 * libusb's API version.
128 * Since version 1.0.13, to help with feature detection, libusb defines
129 * a LIBUSB_API_VERSION macro that gets increased every time there is a
130 * significant change to the API, such as the introduction of a new call,
131 * the definition of a new macro/enum member, or any other element that
132 * libusb applications may want to detect at compilation time.
134 * The macro is typically used in an application as follows:
136 * #if defined(LIBUSB_API_VERSION) && (LIBUSB_API_VERSION >= 0x01001234)
137 * // Use one of the newer features from the libusb API
141 * Internally, LIBUSB_API_VERSION is defined as follows:
142 * (libusb major << 24) | (libusb minor << 16) | (16 bit incremental)
144 #define LIBUSB_API_VERSION 0x01000104
146 /* The following is kept for compatibility, but will be deprecated in the future */
147 #define LIBUSBX_API_VERSION LIBUSB_API_VERSION
155 * Convert a 16-bit value from host-endian to little-endian format. On
156 * little endian systems, this function does nothing. On big endian systems,
157 * the bytes are swapped.
158 * \param x the host-endian value to convert
159 * \returns the value in little-endian byte order
161 static inline uint16_t libusb_cpu_to_le16(const uint16_t x)
167 _tmp.b8[1] = (uint8_t) (x >> 8);
168 _tmp.b8[0] = (uint8_t) (x & 0xff);
172 /** \def libusb_le16_to_cpu
174 * Convert a 16-bit value from little-endian to host-endian format. On
175 * little endian systems, this function does nothing. On big endian systems,
176 * the bytes are swapped.
177 * \param x the little-endian value to convert
178 * \returns the value in host-endian byte order
180 #define libusb_le16_to_cpu libusb_cpu_to_le16
182 /* standard USB stuff */
185 * Device and/or Interface Class codes */
186 enum libusb_class_code {
187 /** In the context of a \ref libusb_device_descriptor "device descriptor",
188 * this bDeviceClass value indicates that each interface specifies its
189 * own class information and all interfaces operate independently.
191 LIBUSB_CLASS_PER_INTERFACE = 0,
194 LIBUSB_CLASS_AUDIO = 1,
196 /** Communications class */
197 LIBUSB_CLASS_COMM = 2,
199 /** Human Interface Device class */
200 LIBUSB_CLASS_HID = 3,
203 LIBUSB_CLASS_PHYSICAL = 5,
206 LIBUSB_CLASS_PRINTER = 7,
209 LIBUSB_CLASS_PTP = 6, /* legacy name from libusb-0.1 usb.h */
210 LIBUSB_CLASS_IMAGE = 6,
212 /** Mass storage class */
213 LIBUSB_CLASS_MASS_STORAGE = 8,
216 LIBUSB_CLASS_HUB = 9,
219 LIBUSB_CLASS_DATA = 10,
222 LIBUSB_CLASS_SMART_CARD = 0x0b,
224 /** Content Security */
225 LIBUSB_CLASS_CONTENT_SECURITY = 0x0d,
228 LIBUSB_CLASS_VIDEO = 0x0e,
230 /** Personal Healthcare */
231 LIBUSB_CLASS_PERSONAL_HEALTHCARE = 0x0f,
233 /** Diagnostic Device */
234 LIBUSB_CLASS_DIAGNOSTIC_DEVICE = 0xdc,
236 /** Wireless class */
237 LIBUSB_CLASS_WIRELESS = 0xe0,
239 /** Application class */
240 LIBUSB_CLASS_APPLICATION = 0xfe,
242 /** Class is vendor-specific */
243 LIBUSB_CLASS_VENDOR_SPEC = 0xff
247 * Descriptor types as defined by the USB specification. */
248 enum libusb_descriptor_type {
249 /** Device descriptor. See libusb_device_descriptor. */
250 LIBUSB_DT_DEVICE = 0x01,
252 /** Configuration descriptor. See libusb_config_descriptor. */
253 LIBUSB_DT_CONFIG = 0x02,
255 /** String descriptor */
256 LIBUSB_DT_STRING = 0x03,
258 /** Interface descriptor. See libusb_interface_descriptor. */
259 LIBUSB_DT_INTERFACE = 0x04,
261 /** Endpoint descriptor. See libusb_endpoint_descriptor. */
262 LIBUSB_DT_ENDPOINT = 0x05,
264 /** BOS descriptor */
265 LIBUSB_DT_BOS = 0x0f,
267 /** Device Capability descriptor */
268 LIBUSB_DT_DEVICE_CAPABILITY = 0x10,
270 /** HID descriptor */
271 LIBUSB_DT_HID = 0x21,
273 /** HID report descriptor */
274 LIBUSB_DT_REPORT = 0x22,
276 /** Physical descriptor */
277 LIBUSB_DT_PHYSICAL = 0x23,
279 /** Hub descriptor */
280 LIBUSB_DT_HUB = 0x29,
282 /** SuperSpeed Hub descriptor */
283 LIBUSB_DT_SUPERSPEED_HUB = 0x2a,
285 /** SuperSpeed Endpoint Companion descriptor */
286 LIBUSB_DT_SS_ENDPOINT_COMPANION = 0x30
289 /* Descriptor sizes per descriptor type */
290 #define LIBUSB_DT_DEVICE_SIZE 18
291 #define LIBUSB_DT_CONFIG_SIZE 9
292 #define LIBUSB_DT_INTERFACE_SIZE 9
293 #define LIBUSB_DT_ENDPOINT_SIZE 7
294 #define LIBUSB_DT_ENDPOINT_AUDIO_SIZE 9 /* Audio extension */
295 #define LIBUSB_DT_HUB_NONVAR_SIZE 7
296 #define LIBUSB_DT_SS_ENDPOINT_COMPANION_SIZE 6
297 #define LIBUSB_DT_BOS_SIZE 5
298 #define LIBUSB_DT_DEVICE_CAPABILITY_SIZE 3
300 /* BOS descriptor sizes */
301 #define LIBUSB_BT_USB_2_0_EXTENSION_SIZE 7
302 #define LIBUSB_BT_SS_USB_DEVICE_CAPABILITY_SIZE 10
303 #define LIBUSB_BT_CONTAINER_ID_SIZE 20
305 /* We unwrap the BOS => define its max size */
306 #define LIBUSB_DT_BOS_MAX_SIZE ((LIBUSB_DT_BOS_SIZE) +\
307 (LIBUSB_BT_USB_2_0_EXTENSION_SIZE) +\
308 (LIBUSB_BT_SS_USB_DEVICE_CAPABILITY_SIZE) +\
309 (LIBUSB_BT_CONTAINER_ID_SIZE))
311 #define LIBUSB_ENDPOINT_ADDRESS_MASK 0x0f /* in bEndpointAddress */
312 #define LIBUSB_ENDPOINT_DIR_MASK 0x80
315 * Endpoint direction. Values for bit 7 of the
316 * \ref libusb_endpoint_descriptor::bEndpointAddress "endpoint address" scheme.
318 enum libusb_endpoint_direction {
319 /** In: device-to-host */
320 LIBUSB_ENDPOINT_IN = 0x80,
322 /** Out: host-to-device */
323 LIBUSB_ENDPOINT_OUT = 0x00
326 #define LIBUSB_TRANSFER_TYPE_MASK 0x03 /* in bmAttributes */
329 * Endpoint transfer type. Values for bits 0:1 of the
330 * \ref libusb_endpoint_descriptor::bmAttributes "endpoint attributes" field.
332 enum libusb_transfer_type {
333 /** Control endpoint */
334 LIBUSB_TRANSFER_TYPE_CONTROL = 0,
336 /** Isochronous endpoint */
337 LIBUSB_TRANSFER_TYPE_ISOCHRONOUS = 1,
340 LIBUSB_TRANSFER_TYPE_BULK = 2,
342 /** Interrupt endpoint */
343 LIBUSB_TRANSFER_TYPE_INTERRUPT = 3,
345 /** Stream endpoint */
346 LIBUSB_TRANSFER_TYPE_BULK_STREAM = 4,
350 * Standard requests, as defined in table 9-5 of the USB 3.0 specifications */
351 enum libusb_standard_request {
352 /** Request status of the specific recipient */
353 LIBUSB_REQUEST_GET_STATUS = 0x00,
355 /** Clear or disable a specific feature */
356 LIBUSB_REQUEST_CLEAR_FEATURE = 0x01,
358 /* 0x02 is reserved */
360 /** Set or enable a specific feature */
361 LIBUSB_REQUEST_SET_FEATURE = 0x03,
363 /* 0x04 is reserved */
365 /** Set device address for all future accesses */
366 LIBUSB_REQUEST_SET_ADDRESS = 0x05,
368 /** Get the specified descriptor */
369 LIBUSB_REQUEST_GET_DESCRIPTOR = 0x06,
371 /** Used to update existing descriptors or add new descriptors */
372 LIBUSB_REQUEST_SET_DESCRIPTOR = 0x07,
374 /** Get the current device configuration value */
375 LIBUSB_REQUEST_GET_CONFIGURATION = 0x08,
377 /** Set device configuration */
378 LIBUSB_REQUEST_SET_CONFIGURATION = 0x09,
380 /** Return the selected alternate setting for the specified interface */
381 LIBUSB_REQUEST_GET_INTERFACE = 0x0A,
383 /** Select an alternate interface for the specified interface */
384 LIBUSB_REQUEST_SET_INTERFACE = 0x0B,
386 /** Set then report an endpoint's synchronization frame */
387 LIBUSB_REQUEST_SYNCH_FRAME = 0x0C,
389 /** Sets both the U1 and U2 Exit Latency */
390 LIBUSB_REQUEST_SET_SEL = 0x30,
392 /** Delay from the time a host transmits a packet to the time it is
393 * received by the device. */
394 LIBUSB_SET_ISOCH_DELAY = 0x31,
398 * Request type bits of the
399 * \ref libusb_control_setup::bmRequestType "bmRequestType" field in control
401 enum libusb_request_type {
403 LIBUSB_REQUEST_TYPE_STANDARD = (0x00 << 5),
406 LIBUSB_REQUEST_TYPE_CLASS = (0x01 << 5),
409 LIBUSB_REQUEST_TYPE_VENDOR = (0x02 << 5),
412 LIBUSB_REQUEST_TYPE_RESERVED = (0x03 << 5)
416 * Recipient bits of the
417 * \ref libusb_control_setup::bmRequestType "bmRequestType" field in control
418 * transfers. Values 4 through 31 are reserved. */
419 enum libusb_request_recipient {
421 LIBUSB_RECIPIENT_DEVICE = 0x00,
424 LIBUSB_RECIPIENT_INTERFACE = 0x01,
427 LIBUSB_RECIPIENT_ENDPOINT = 0x02,
430 LIBUSB_RECIPIENT_OTHER = 0x03,
433 #define LIBUSB_ISO_SYNC_TYPE_MASK 0x0C
436 * Synchronization type for isochronous endpoints. Values for bits 2:3 of the
437 * \ref libusb_endpoint_descriptor::bmAttributes "bmAttributes" field in
438 * libusb_endpoint_descriptor.
440 enum libusb_iso_sync_type {
441 /** No synchronization */
442 LIBUSB_ISO_SYNC_TYPE_NONE = 0,
445 LIBUSB_ISO_SYNC_TYPE_ASYNC = 1,
448 LIBUSB_ISO_SYNC_TYPE_ADAPTIVE = 2,
451 LIBUSB_ISO_SYNC_TYPE_SYNC = 3
454 #define LIBUSB_ISO_USAGE_TYPE_MASK 0x30
457 * Usage type for isochronous endpoints. Values for bits 4:5 of the
458 * \ref libusb_endpoint_descriptor::bmAttributes "bmAttributes" field in
459 * libusb_endpoint_descriptor.
461 enum libusb_iso_usage_type {
463 LIBUSB_ISO_USAGE_TYPE_DATA = 0,
465 /** Feedback endpoint */
466 LIBUSB_ISO_USAGE_TYPE_FEEDBACK = 1,
468 /** Implicit feedback Data endpoint */
469 LIBUSB_ISO_USAGE_TYPE_IMPLICIT = 2,
473 * A structure representing the standard USB device descriptor. This
474 * descriptor is documented in section 9.6.1 of the USB 3.0 specification.
475 * All multiple-byte fields are represented in host-endian format.
477 struct libusb_device_descriptor {
478 /** Size of this descriptor (in bytes) */
481 /** Descriptor type. Will have value
482 * \ref libusb_descriptor_type::LIBUSB_DT_DEVICE LIBUSB_DT_DEVICE in this
484 uint8_t bDescriptorType;
486 /** USB specification release number in binary-coded decimal. A value of
487 * 0x0200 indicates USB 2.0, 0x0110 indicates USB 1.1, etc. */
490 /** USB-IF class code for the device. See \ref libusb_class_code. */
491 uint8_t bDeviceClass;
493 /** USB-IF subclass code for the device, qualified by the bDeviceClass
495 uint8_t bDeviceSubClass;
497 /** USB-IF protocol code for the device, qualified by the bDeviceClass and
498 * bDeviceSubClass values */
499 uint8_t bDeviceProtocol;
501 /** Maximum packet size for endpoint 0 */
502 uint8_t bMaxPacketSize0;
504 /** USB-IF vendor ID */
507 /** USB-IF product ID */
510 /** Device release number in binary-coded decimal */
513 /** Index of string descriptor describing manufacturer */
514 uint8_t iManufacturer;
516 /** Index of string descriptor describing product */
519 /** Index of string descriptor containing device serial number */
520 uint8_t iSerialNumber;
522 /** Number of possible configurations */
523 uint8_t bNumConfigurations;
527 * A structure representing the standard USB endpoint descriptor. This
528 * descriptor is documented in section 9.6.6 of the USB 3.0 specification.
529 * All multiple-byte fields are represented in host-endian format.
531 struct libusb_endpoint_descriptor {
532 /** Size of this descriptor (in bytes) */
535 /** Descriptor type. Will have value
536 * \ref libusb_descriptor_type::LIBUSB_DT_ENDPOINT LIBUSB_DT_ENDPOINT in
538 uint8_t bDescriptorType;
540 /** The address of the endpoint described by this descriptor. Bits 0:3 are
541 * the endpoint number. Bits 4:6 are reserved. Bit 7 indicates direction,
542 * see \ref libusb_endpoint_direction.
544 uint8_t bEndpointAddress;
546 /** Attributes which apply to the endpoint when it is configured using
547 * the bConfigurationValue. Bits 0:1 determine the transfer type and
548 * correspond to \ref libusb_transfer_type. Bits 2:3 are only used for
549 * isochronous endpoints and correspond to \ref libusb_iso_sync_type.
550 * Bits 4:5 are also only used for isochronous endpoints and correspond to
551 * \ref libusb_iso_usage_type. Bits 6:7 are reserved.
553 uint8_t bmAttributes;
555 /** Maximum packet size this endpoint is capable of sending/receiving. */
556 uint16_t wMaxPacketSize;
558 /** Interval for polling endpoint for data transfers. */
561 /** For audio devices only: the rate at which synchronization feedback
565 /** For audio devices only: the address if the synch endpoint */
566 uint8_t bSynchAddress;
568 /** Extra descriptors. If libusb encounters unknown endpoint descriptors,
569 * it will store them here, should you wish to parse them. */
570 const unsigned char *extra;
572 /** Length of the extra descriptors, in bytes. */
577 * A structure representing the standard USB interface descriptor. This
578 * descriptor is documented in section 9.6.5 of the USB 3.0 specification.
579 * All multiple-byte fields are represented in host-endian format.
581 struct libusb_interface_descriptor {
582 /** Size of this descriptor (in bytes) */
585 /** Descriptor type. Will have value
586 * \ref libusb_descriptor_type::LIBUSB_DT_INTERFACE LIBUSB_DT_INTERFACE
587 * in this context. */
588 uint8_t bDescriptorType;
590 /** Number of this interface */
591 uint8_t bInterfaceNumber;
593 /** Value used to select this alternate setting for this interface */
594 uint8_t bAlternateSetting;
596 /** Number of endpoints used by this interface (excluding the control
598 uint8_t bNumEndpoints;
600 /** USB-IF class code for this interface. See \ref libusb_class_code. */
601 uint8_t bInterfaceClass;
603 /** USB-IF subclass code for this interface, qualified by the
604 * bInterfaceClass value */
605 uint8_t bInterfaceSubClass;
607 /** USB-IF protocol code for this interface, qualified by the
608 * bInterfaceClass and bInterfaceSubClass values */
609 uint8_t bInterfaceProtocol;
611 /** Index of string descriptor describing this interface */
614 /** Array of endpoint descriptors. This length of this array is determined
615 * by the bNumEndpoints field. */
616 const struct libusb_endpoint_descriptor *endpoint;
618 /** Extra descriptors. If libusb encounters unknown interface descriptors,
619 * it will store them here, should you wish to parse them. */
620 const unsigned char *extra;
622 /** Length of the extra descriptors, in bytes. */
627 * A collection of alternate settings for a particular USB interface.
629 struct libusb_interface {
630 /** Array of interface descriptors. The length of this array is determined
631 * by the num_altsetting field. */
632 const struct libusb_interface_descriptor *altsetting;
634 /** The number of alternate settings that belong to this interface */
639 * A structure representing the standard USB configuration descriptor. This
640 * descriptor is documented in section 9.6.3 of the USB 3.0 specification.
641 * All multiple-byte fields are represented in host-endian format.
643 struct libusb_config_descriptor {
644 /** Size of this descriptor (in bytes) */
647 /** Descriptor type. Will have value
648 * \ref libusb_descriptor_type::LIBUSB_DT_CONFIG LIBUSB_DT_CONFIG
649 * in this context. */
650 uint8_t bDescriptorType;
652 /** Total length of data returned for this configuration */
653 uint16_t wTotalLength;
655 /** Number of interfaces supported by this configuration */
656 uint8_t bNumInterfaces;
658 /** Identifier value for this configuration */
659 uint8_t bConfigurationValue;
661 /** Index of string descriptor describing this configuration */
662 uint8_t iConfiguration;
664 /** Configuration characteristics */
665 uint8_t bmAttributes;
667 /** Maximum power consumption of the USB device from this bus in this
668 * configuration when the device is fully operation. Expressed in units
669 * of 2 mA when the device is operating in high-speed mode and in units
670 * of 8 mA when the device is operating in super-speed mode. */
673 /** Array of interfaces supported by this configuration. The length of
674 * this array is determined by the bNumInterfaces field. */
675 const struct libusb_interface *interface;
677 /** Extra descriptors. If libusb encounters unknown configuration
678 * descriptors, it will store them here, should you wish to parse them. */
679 const unsigned char *extra;
681 /** Length of the extra descriptors, in bytes. */
686 * A structure representing the superspeed endpoint companion
687 * descriptor. This descriptor is documented in section 9.6.7 of
688 * the USB 3.0 specification. All multiple-byte fields are represented in
689 * host-endian format.
691 struct libusb_ss_endpoint_companion_descriptor {
693 /** Size of this descriptor (in bytes) */
696 /** Descriptor type. Will have value
697 * \ref libusb_descriptor_type::LIBUSB_DT_SS_ENDPOINT_COMPANION in
699 uint8_t bDescriptorType;
702 /** The maximum number of packets the endpoint can send or
703 * recieve as part of a burst. */
706 /** In bulk EP: bits 4:0 represents the maximum number of
707 * streams the EP supports. In isochronous EP: bits 1:0
708 * represents the Mult - a zero based value that determines
709 * the maximum number of packets within a service interval */
710 uint8_t bmAttributes;
712 /** The total number of bytes this EP will transfer every
713 * service interval. valid only for periodic EPs. */
714 uint16_t wBytesPerInterval;
718 * A generic representation of a BOS Device Capability descriptor. It is
719 * advised to check bDevCapabilityType and call the matching
720 * libusb_get_*_descriptor function to get a structure fully matching the type.
722 struct libusb_bos_dev_capability_descriptor {
723 /** Size of this descriptor (in bytes) */
725 /** Descriptor type. Will have value
726 * \ref libusb_descriptor_type::LIBUSB_DT_DEVICE_CAPABILITY
727 * LIBUSB_DT_DEVICE_CAPABILITY in this context. */
728 uint8_t bDescriptorType;
729 /** Device Capability type */
730 uint8_t bDevCapabilityType;
731 /** Device Capability data (bLength - 3 bytes) */
732 uint8_t dev_capability_data
733 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
734 [] /* valid C99 code */
736 [0] /* non-standard, but usually working code */
742 * A structure representing the Binary Device Object Store (BOS) descriptor.
743 * This descriptor is documented in section 9.6.2 of the USB 3.0 specification.
744 * All multiple-byte fields are represented in host-endian format.
746 struct libusb_bos_descriptor {
747 /** Size of this descriptor (in bytes) */
750 /** Descriptor type. Will have value
751 * \ref libusb_descriptor_type::LIBUSB_DT_BOS LIBUSB_DT_BOS
752 * in this context. */
753 uint8_t bDescriptorType;
755 /** Length of this descriptor and all of its sub descriptors */
756 uint16_t wTotalLength;
758 /** The number of separate device capability descriptors in
760 uint8_t bNumDeviceCaps;
762 /** bNumDeviceCap Device Capability Descriptors */
763 struct libusb_bos_dev_capability_descriptor *dev_capability
764 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
765 [] /* valid C99 code */
767 [0] /* non-standard, but usually working code */
773 * A structure representing the USB 2.0 Extension descriptor
774 * This descriptor is documented in section 9.6.2.1 of the USB 3.0 specification.
775 * All multiple-byte fields are represented in host-endian format.
777 struct libusb_usb_2_0_extension_descriptor {
778 /** Size of this descriptor (in bytes) */
781 /** Descriptor type. Will have value
782 * \ref libusb_descriptor_type::LIBUSB_DT_DEVICE_CAPABILITY
783 * LIBUSB_DT_DEVICE_CAPABILITY in this context. */
784 uint8_t bDescriptorType;
786 /** Capability type. Will have value
787 * \ref libusb_capability_type::LIBUSB_BT_USB_2_0_EXTENSION
788 * LIBUSB_BT_USB_2_0_EXTENSION in this context. */
789 uint8_t bDevCapabilityType;
791 /** Bitmap encoding of supported device level features.
792 * A value of one in a bit location indicates a feature is
793 * supported; a value of zero indicates it is not supported.
794 * See \ref libusb_usb_2_0_extension_attributes. */
795 uint32_t bmAttributes;
799 * A structure representing the SuperSpeed USB Device Capability descriptor
800 * This descriptor is documented in section 9.6.2.2 of the USB 3.0 specification.
801 * All multiple-byte fields are represented in host-endian format.
803 struct libusb_ss_usb_device_capability_descriptor {
804 /** Size of this descriptor (in bytes) */
807 /** Descriptor type. Will have value
808 * \ref libusb_descriptor_type::LIBUSB_DT_DEVICE_CAPABILITY
809 * LIBUSB_DT_DEVICE_CAPABILITY in this context. */
810 uint8_t bDescriptorType;
812 /** Capability type. Will have value
813 * \ref libusb_capability_type::LIBUSB_BT_SS_USB_DEVICE_CAPABILITY
814 * LIBUSB_BT_SS_USB_DEVICE_CAPABILITY in this context. */
815 uint8_t bDevCapabilityType;
817 /** Bitmap encoding of supported device level features.
818 * A value of one in a bit location indicates a feature is
819 * supported; a value of zero indicates it is not supported.
820 * See \ref libusb_ss_usb_device_capability_attributes. */
821 uint8_t bmAttributes;
823 /** Bitmap encoding of the speed supported by this device when
824 * operating in SuperSpeed mode. See \ref libusb_supported_speed. */
825 uint16_t wSpeedSupported;
827 /** The lowest speed at which all the functionality supported
828 * by the device is available to the user. For example if the
829 * device supports all its functionality when connected at
830 * full speed and above then it sets this value to 1. */
831 uint8_t bFunctionalitySupport;
833 /** U1 Device Exit Latency. */
834 uint8_t bU1DevExitLat;
836 /** U2 Device Exit Latency. */
837 uint16_t bU2DevExitLat;
841 * A structure representing the Container ID descriptor.
842 * This descriptor is documented in section 9.6.2.3 of the USB 3.0 specification.
843 * All multiple-byte fields, except UUIDs, are represented in host-endian format.
845 struct libusb_container_id_descriptor {
846 /** Size of this descriptor (in bytes) */
849 /** Descriptor type. Will have value
850 * \ref libusb_descriptor_type::LIBUSB_DT_DEVICE_CAPABILITY
851 * LIBUSB_DT_DEVICE_CAPABILITY in this context. */
852 uint8_t bDescriptorType;
854 /** Capability type. Will have value
855 * \ref libusb_capability_type::LIBUSB_BT_CONTAINER_ID
856 * LIBUSB_BT_CONTAINER_ID in this context. */
857 uint8_t bDevCapabilityType;
859 /** Reserved field */
863 uint8_t ContainerID[16];
867 * Setup packet for control transfers. */
868 struct libusb_control_setup {
869 /** Request type. Bits 0:4 determine recipient, see
870 * \ref libusb_request_recipient. Bits 5:6 determine type, see
871 * \ref libusb_request_type. Bit 7 determines data transfer direction, see
872 * \ref libusb_endpoint_direction.
874 uint8_t bmRequestType;
876 /** Request. If the type bits of bmRequestType are equal to
877 * \ref libusb_request_type::LIBUSB_REQUEST_TYPE_STANDARD
878 * "LIBUSB_REQUEST_TYPE_STANDARD" then this field refers to
879 * \ref libusb_standard_request. For other cases, use of this field is
880 * application-specific. */
883 /** Value. Varies according to request */
886 /** Index. Varies according to request, typically used to pass an index
890 /** Number of bytes to transfer */
894 #define LIBUSB_CONTROL_SETUP_SIZE (sizeof(struct libusb_control_setup))
898 struct libusb_context;
899 struct libusb_device;
900 struct libusb_device_handle;
903 * Structure providing the version of the libusb runtime
905 struct libusb_version {
906 /** Library major version. */
907 const uint16_t major;
909 /** Library minor version. */
910 const uint16_t minor;
912 /** Library micro version. */
913 const uint16_t micro;
915 /** Library nano version. */
918 /** Library release candidate suffix string, e.g. "-rc4". */
921 /** For ABI compatibility only. */
922 const char* describe;
926 * Structure representing a libusb session. The concept of individual libusb
927 * sessions allows for your program to use two libraries (or dynamically
928 * load two modules) which both independently use libusb. This will prevent
929 * interference between the individual libusb users - for example
930 * libusb_set_debug() will not affect the other user of the library, and
931 * libusb_exit() will not destroy resources that the other user is still
934 * Sessions are created by libusb_init() and destroyed through libusb_exit().
935 * If your application is guaranteed to only ever include a single libusb
936 * user (i.e. you), you do not have to worry about contexts: pass NULL in
937 * every function call where a context is required. The default context
940 * For more information, see \ref contexts.
942 typedef struct libusb_context libusb_context;
945 * Structure representing a USB device detected on the system. This is an
946 * opaque type for which you are only ever provided with a pointer, usually
947 * originating from libusb_get_device_list().
949 * Certain operations can be performed on a device, but in order to do any
950 * I/O you will have to first obtain a device handle using libusb_open().
952 * Devices are reference counted with libusb_ref_device() and
953 * libusb_unref_device(), and are freed when the reference count reaches 0.
954 * New devices presented by libusb_get_device_list() have a reference count of
955 * 1, and libusb_free_device_list() can optionally decrease the reference count
956 * on all devices in the list. libusb_open() adds another reference which is
957 * later destroyed by libusb_close().
959 typedef struct libusb_device libusb_device;
963 * Structure representing a handle on a USB device. This is an opaque type for
964 * which you are only ever provided with a pointer, usually originating from
967 * A device handle is used to perform I/O and other operations. When finished
968 * with a device handle, you should call libusb_close().
970 typedef struct libusb_device_handle libusb_device_handle;
973 * Speed codes. Indicates the speed at which the device is operating.
976 /** The OS doesn't report or know the device speed. */
977 LIBUSB_SPEED_UNKNOWN = 0,
979 /** The device is operating at low speed (1.5MBit/s). */
980 LIBUSB_SPEED_LOW = 1,
982 /** The device is operating at full speed (12MBit/s). */
983 LIBUSB_SPEED_FULL = 2,
985 /** The device is operating at high speed (480MBit/s). */
986 LIBUSB_SPEED_HIGH = 3,
988 /** The device is operating at super speed (5000MBit/s). */
989 LIBUSB_SPEED_SUPER = 4,
993 * Supported speeds (wSpeedSupported) bitfield. Indicates what
994 * speeds the device supports.
996 enum libusb_supported_speed {
997 /** Low speed operation supported (1.5MBit/s). */
998 LIBUSB_LOW_SPEED_OPERATION = 1,
1000 /** Full speed operation supported (12MBit/s). */
1001 LIBUSB_FULL_SPEED_OPERATION = 2,
1003 /** High speed operation supported (480MBit/s). */
1004 LIBUSB_HIGH_SPEED_OPERATION = 4,
1006 /** Superspeed operation supported (5000MBit/s). */
1007 LIBUSB_SUPER_SPEED_OPERATION = 8,
1011 * Masks for the bits of the
1012 * \ref libusb_usb_2_0_extension_descriptor::bmAttributes "bmAttributes" field
1013 * of the USB 2.0 Extension descriptor.
1015 enum libusb_usb_2_0_extension_attributes {
1016 /** Supports Link Power Management (LPM) */
1017 LIBUSB_BM_LPM_SUPPORT = 2,
1021 * Masks for the bits of the
1022 * \ref libusb_ss_usb_device_capability_descriptor::bmAttributes "bmAttributes" field
1023 * field of the SuperSpeed USB Device Capability descriptor.
1025 enum libusb_ss_usb_device_capability_attributes {
1026 /** Supports Latency Tolerance Messages (LTM) */
1027 LIBUSB_BM_LTM_SUPPORT = 2,
1031 * USB capability types
1033 enum libusb_bos_type {
1034 /** Wireless USB device capability */
1035 LIBUSB_BT_WIRELESS_USB_DEVICE_CAPABILITY = 1,
1037 /** USB 2.0 extensions */
1038 LIBUSB_BT_USB_2_0_EXTENSION = 2,
1040 /** SuperSpeed USB device capability */
1041 LIBUSB_BT_SS_USB_DEVICE_CAPABILITY = 3,
1043 /** Container ID type */
1044 LIBUSB_BT_CONTAINER_ID = 4,
1048 * Error codes. Most libusb functions return 0 on success or one of these
1050 * You can call libusb_error_name() to retrieve a string representation of an
1051 * error code or libusb_strerror() to get an end-user suitable description of
1055 /** Success (no error) */
1058 /** Input/output error */
1059 LIBUSB_ERROR_IO = -1,
1061 /** Invalid parameter */
1062 LIBUSB_ERROR_INVALID_PARAM = -2,
1064 /** Access denied (insufficient permissions) */
1065 LIBUSB_ERROR_ACCESS = -3,
1067 /** No such device (it may have been disconnected) */
1068 LIBUSB_ERROR_NO_DEVICE = -4,
1070 /** Entity not found */
1071 LIBUSB_ERROR_NOT_FOUND = -5,
1073 /** Resource busy */
1074 LIBUSB_ERROR_BUSY = -6,
1076 /** Operation timed out */
1077 LIBUSB_ERROR_TIMEOUT = -7,
1080 LIBUSB_ERROR_OVERFLOW = -8,
1083 LIBUSB_ERROR_PIPE = -9,
1085 /** System call interrupted (perhaps due to signal) */
1086 LIBUSB_ERROR_INTERRUPTED = -10,
1088 /** Insufficient memory */
1089 LIBUSB_ERROR_NO_MEM = -11,
1091 /** Operation not supported or unimplemented on this platform */
1092 LIBUSB_ERROR_NOT_SUPPORTED = -12,
1094 /* NB: Remember to update LIBUSB_ERROR_COUNT below as well as the
1095 message strings in strerror.c when adding new error codes here. */
1098 LIBUSB_ERROR_OTHER = -99,
1101 /* Total number of error codes in enum libusb_error */
1102 #define LIBUSB_ERROR_COUNT 14
1104 /** \ingroup asyncio
1105 * Transfer status codes */
1106 enum libusb_transfer_status {
1107 /** Transfer completed without error. Note that this does not indicate
1108 * that the entire amount of requested data was transferred. */
1109 LIBUSB_TRANSFER_COMPLETED,
1111 /** Transfer failed */
1112 LIBUSB_TRANSFER_ERROR,
1114 /** Transfer timed out */
1115 LIBUSB_TRANSFER_TIMED_OUT,
1117 /** Transfer was cancelled */
1118 LIBUSB_TRANSFER_CANCELLED,
1120 /** For bulk/interrupt endpoints: halt condition detected (endpoint
1121 * stalled). For control endpoints: control request not supported. */
1122 LIBUSB_TRANSFER_STALL,
1124 /** Device was disconnected */
1125 LIBUSB_TRANSFER_NO_DEVICE,
1127 /** Device sent more data than requested */
1128 LIBUSB_TRANSFER_OVERFLOW,
1130 /* NB! Remember to update libusb_error_name()
1131 when adding new status codes here. */
1134 /** \ingroup asyncio
1135 * libusb_transfer.flags values */
1136 enum libusb_transfer_flags {
1137 /** Report short frames as errors */
1138 LIBUSB_TRANSFER_SHORT_NOT_OK = 1<<0,
1140 /** Automatically free() transfer buffer during libusb_free_transfer() */
1141 LIBUSB_TRANSFER_FREE_BUFFER = 1<<1,
1143 /** Automatically call libusb_free_transfer() after callback returns.
1144 * If this flag is set, it is illegal to call libusb_free_transfer()
1145 * from your transfer callback, as this will result in a double-free
1146 * when this flag is acted upon. */
1147 LIBUSB_TRANSFER_FREE_TRANSFER = 1<<2,
1149 /** Terminate transfers that are a multiple of the endpoint's
1150 * wMaxPacketSize with an extra zero length packet. This is useful
1151 * when a device protocol mandates that each logical request is
1152 * terminated by an incomplete packet (i.e. the logical requests are
1153 * not separated by other means).
1155 * This flag only affects host-to-device transfers to bulk and interrupt
1156 * endpoints. In other situations, it is ignored.
1158 * This flag only affects transfers with a length that is a multiple of
1159 * the endpoint's wMaxPacketSize. On transfers of other lengths, this
1160 * flag has no effect. Therefore, if you are working with a device that
1161 * needs a ZLP whenever the end of the logical request falls on a packet
1162 * boundary, then it is sensible to set this flag on <em>every</em>
1163 * transfer (you do not have to worry about only setting it on transfers
1164 * that end on the boundary).
1166 * This flag is currently only supported on Linux.
1167 * On other systems, libusb_submit_transfer() will return
1168 * LIBUSB_ERROR_NOT_SUPPORTED for every transfer where this flag is set.
1170 * Available since libusb-1.0.9.
1172 LIBUSB_TRANSFER_ADD_ZERO_PACKET = 1 << 3,
1175 /** \ingroup asyncio
1176 * Isochronous packet descriptor. */
1177 struct libusb_iso_packet_descriptor {
1178 /** Length of data to request in this packet */
1179 unsigned int length;
1181 /** Amount of data that was actually transferred */
1182 unsigned int actual_length;
1184 /** Status code for this packet */
1185 enum libusb_transfer_status status;
1188 struct libusb_transfer;
1190 /** \ingroup asyncio
1191 * Asynchronous transfer callback function type. When submitting asynchronous
1192 * transfers, you pass a pointer to a callback function of this type via the
1193 * \ref libusb_transfer::callback "callback" member of the libusb_transfer
1194 * structure. libusb will call this function later, when the transfer has
1195 * completed or failed. See \ref asyncio for more information.
1196 * \param transfer The libusb_transfer struct the callback function is being
1199 typedef void (LIBUSB_CALL *libusb_transfer_cb_fn)(struct libusb_transfer *transfer);
1201 /** \ingroup asyncio
1202 * The generic USB transfer structure. The user populates this structure and
1203 * then submits it in order to request a transfer. After the transfer has
1204 * completed, the library populates the transfer with the results and passes
1205 * it back to the user.
1207 struct libusb_transfer {
1208 /** Handle of the device that this transfer will be submitted to */
1209 libusb_device_handle *dev_handle;
1211 /** A bitwise OR combination of \ref libusb_transfer_flags. */
1214 /** Address of the endpoint where this transfer will be sent. */
1215 unsigned char endpoint;
1217 /** Type of the endpoint from \ref libusb_transfer_type */
1220 /** Timeout for this transfer in millseconds. A value of 0 indicates no
1222 unsigned int timeout;
1224 /** The status of the transfer. Read-only, and only for use within
1225 * transfer callback function.
1227 * If this is an isochronous transfer, this field may read COMPLETED even
1228 * if there were errors in the frames. Use the
1229 * \ref libusb_iso_packet_descriptor::status "status" field in each packet
1230 * to determine if errors occurred. */
1231 enum libusb_transfer_status status;
1233 /** Length of the data buffer */
1236 /** Actual length of data that was transferred. Read-only, and only for
1237 * use within transfer callback function. Not valid for isochronous
1238 * endpoint transfers. */
1241 /** Callback function. This will be invoked when the transfer completes,
1242 * fails, or is cancelled. */
1243 libusb_transfer_cb_fn callback;
1245 /** User context data to pass to the callback function. */
1249 unsigned char *buffer;
1251 /** Number of isochronous packets. Only used for I/O with isochronous
1253 int num_iso_packets;
1255 /** Isochronous packet descriptors, for isochronous transfers only. */
1256 struct libusb_iso_packet_descriptor iso_packet_desc
1257 #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
1258 [] /* valid C99 code */
1260 [0] /* non-standard, but usually working code */
1266 * Capabilities supported by an instance of libusb on the current running
1267 * platform. Test if the loaded library supports a given capability by calling
1268 * \ref libusb_has_capability().
1270 enum libusb_capability {
1271 /** The libusb_has_capability() API is available. */
1272 LIBUSB_CAP_HAS_CAPABILITY = 0x0000,
1273 /** Hotplug support is available on this platform. */
1274 LIBUSB_CAP_HAS_HOTPLUG = 0x0001,
1275 /** The library can access HID devices without requiring user intervention.
1276 * Note that before being able to actually access an HID device, you may
1277 * still have to call additional libusb functions such as
1278 * \ref libusb_detach_kernel_driver(). */
1279 LIBUSB_CAP_HAS_HID_ACCESS = 0x0100,
1280 /** The library supports detaching of the default USB driver, using
1281 * \ref libusb_detach_kernel_driver(), if one is set by the OS kernel */
1282 LIBUSB_CAP_SUPPORTS_DETACH_KERNEL_DRIVER = 0x0101
1286 * Log message levels.
1287 * - LIBUSB_LOG_LEVEL_NONE (0) : no messages ever printed by the library (default)
1288 * - LIBUSB_LOG_LEVEL_ERROR (1) : error messages are printed to stderr
1289 * - LIBUSB_LOG_LEVEL_WARNING (2) : warning and error messages are printed to stderr
1290 * - LIBUSB_LOG_LEVEL_INFO (3) : informational messages are printed to stdout, warning
1291 * and error messages are printed to stderr
1292 * - LIBUSB_LOG_LEVEL_DEBUG (4) : debug and informational messages are printed to stdout,
1293 * warnings and errors to stderr
1295 enum libusb_log_level {
1296 LIBUSB_LOG_LEVEL_NONE = 0,
1297 LIBUSB_LOG_LEVEL_ERROR,
1298 LIBUSB_LOG_LEVEL_WARNING,
1299 LIBUSB_LOG_LEVEL_INFO,
1300 LIBUSB_LOG_LEVEL_DEBUG,
1303 int LIBUSB_CALL libusb_init(libusb_context **ctx);
1304 void LIBUSB_CALL libusb_exit(libusb_context *ctx);
1305 void LIBUSB_CALL libusb_set_debug(libusb_context *ctx, int level);
1306 const struct libusb_version * LIBUSB_CALL libusb_get_version(void);
1307 int LIBUSB_CALL libusb_has_capability(uint32_t capability);
1308 const char * LIBUSB_CALL libusb_error_name(int errcode);
1309 int LIBUSB_CALL libusb_setlocale(const char *locale);
1310 const char * LIBUSB_CALL libusb_strerror(enum libusb_error errcode);
1312 ssize_t LIBUSB_CALL libusb_get_device_list(libusb_context *ctx,
1313 libusb_device ***list);
1314 void LIBUSB_CALL libusb_free_device_list(libusb_device **list,
1316 libusb_device * LIBUSB_CALL libusb_ref_device(libusb_device *dev);
1317 void LIBUSB_CALL libusb_unref_device(libusb_device *dev);
1319 int LIBUSB_CALL libusb_get_configuration(libusb_device_handle *dev,
1321 int LIBUSB_CALL libusb_get_device_descriptor(libusb_device *dev,
1322 struct libusb_device_descriptor *desc);
1323 int LIBUSB_CALL libusb_get_active_config_descriptor(libusb_device *dev,
1324 struct libusb_config_descriptor **config);
1325 int LIBUSB_CALL libusb_get_config_descriptor(libusb_device *dev,
1326 uint8_t config_index, struct libusb_config_descriptor **config);
1327 int LIBUSB_CALL libusb_get_config_descriptor_by_value(libusb_device *dev,
1328 uint8_t bConfigurationValue, struct libusb_config_descriptor **config);
1329 void LIBUSB_CALL libusb_free_config_descriptor(
1330 struct libusb_config_descriptor *config);
1331 int LIBUSB_CALL libusb_get_ss_endpoint_companion_descriptor(
1332 struct libusb_context *ctx,
1333 const struct libusb_endpoint_descriptor *endpoint,
1334 struct libusb_ss_endpoint_companion_descriptor **ep_comp);
1335 void LIBUSB_CALL libusb_free_ss_endpoint_companion_descriptor(
1336 struct libusb_ss_endpoint_companion_descriptor *ep_comp);
1337 int LIBUSB_CALL libusb_get_bos_descriptor(libusb_device_handle *handle,
1338 struct libusb_bos_descriptor **bos);
1339 void LIBUSB_CALL libusb_free_bos_descriptor(struct libusb_bos_descriptor *bos);
1340 int LIBUSB_CALL libusb_get_usb_2_0_extension_descriptor(
1341 struct libusb_context *ctx,
1342 struct libusb_bos_dev_capability_descriptor *dev_cap,
1343 struct libusb_usb_2_0_extension_descriptor **usb_2_0_extension);
1344 void LIBUSB_CALL libusb_free_usb_2_0_extension_descriptor(
1345 struct libusb_usb_2_0_extension_descriptor *usb_2_0_extension);
1346 int LIBUSB_CALL libusb_get_ss_usb_device_capability_descriptor(
1347 struct libusb_context *ctx,
1348 struct libusb_bos_dev_capability_descriptor *dev_cap,
1349 struct libusb_ss_usb_device_capability_descriptor **ss_usb_device_cap);
1350 void LIBUSB_CALL libusb_free_ss_usb_device_capability_descriptor(
1351 struct libusb_ss_usb_device_capability_descriptor *ss_usb_device_cap);
1352 int LIBUSB_CALL libusb_get_container_id_descriptor(struct libusb_context *ctx,
1353 struct libusb_bos_dev_capability_descriptor *dev_cap,
1354 struct libusb_container_id_descriptor **container_id);
1355 void LIBUSB_CALL libusb_free_container_id_descriptor(
1356 struct libusb_container_id_descriptor *container_id);
1357 uint8_t LIBUSB_CALL libusb_get_bus_number(libusb_device *dev);
1358 uint8_t LIBUSB_CALL libusb_get_port_number(libusb_device *dev);
1359 int LIBUSB_CALL libusb_get_port_numbers(libusb_device *dev, uint8_t* port_numbers, int port_numbers_len);
1360 LIBUSB_DEPRECATED_FOR(libusb_get_port_numbers)
1361 int LIBUSB_CALL libusb_get_port_path(libusb_context *ctx, libusb_device *dev, uint8_t* path, uint8_t path_length);
1362 libusb_device * LIBUSB_CALL libusb_get_parent(libusb_device *dev);
1363 uint8_t LIBUSB_CALL libusb_get_device_address(libusb_device *dev);
1364 int LIBUSB_CALL libusb_get_device_speed(libusb_device *dev);
1365 int LIBUSB_CALL libusb_get_max_packet_size(libusb_device *dev,
1366 unsigned char endpoint);
1367 int LIBUSB_CALL libusb_get_max_iso_packet_size(libusb_device *dev,
1368 unsigned char endpoint);
1370 int LIBUSB_CALL libusb_open(libusb_device *dev, libusb_device_handle **handle);
1371 void LIBUSB_CALL libusb_close(libusb_device_handle *dev_handle);
1372 libusb_device * LIBUSB_CALL libusb_get_device(libusb_device_handle *dev_handle);
1374 int LIBUSB_CALL libusb_set_configuration(libusb_device_handle *dev,
1376 int LIBUSB_CALL libusb_claim_interface(libusb_device_handle *dev,
1377 int interface_number);
1378 int LIBUSB_CALL libusb_release_interface(libusb_device_handle *dev,
1379 int interface_number);
1381 libusb_device_handle * LIBUSB_CALL libusb_open_device_with_vid_pid(
1382 libusb_context *ctx, uint16_t vendor_id, uint16_t product_id);
1384 int LIBUSB_CALL libusb_set_interface_alt_setting(libusb_device_handle *dev,
1385 int interface_number, int alternate_setting);
1386 int LIBUSB_CALL libusb_clear_halt(libusb_device_handle *dev,
1387 unsigned char endpoint);
1388 int LIBUSB_CALL libusb_reset_device(libusb_device_handle *dev);
1390 int LIBUSB_CALL libusb_alloc_streams(libusb_device_handle *dev,
1391 uint32_t num_streams, unsigned char *endpoints, int num_endpoints);
1392 int LIBUSB_CALL libusb_free_streams(libusb_device_handle *dev,
1393 unsigned char *endpoints, int num_endpoints);
1395 int LIBUSB_CALL libusb_kernel_driver_active(libusb_device_handle *dev,
1396 int interface_number);
1397 int LIBUSB_CALL libusb_detach_kernel_driver(libusb_device_handle *dev,
1398 int interface_number);
1399 int LIBUSB_CALL libusb_attach_kernel_driver(libusb_device_handle *dev,
1400 int interface_number);
1401 int LIBUSB_CALL libusb_set_auto_detach_kernel_driver(
1402 libusb_device_handle *dev, int enable);
1406 /** \ingroup asyncio
1407 * Get the data section of a control transfer. This convenience function is here
1408 * to remind you that the data does not start until 8 bytes into the actual
1409 * buffer, as the setup packet comes first.
1411 * Calling this function only makes sense from a transfer callback function,
1412 * or situations where you have already allocated a suitably sized buffer at
1415 * \param transfer a transfer
1416 * \returns pointer to the first byte of the data section
1418 static inline unsigned char *libusb_control_transfer_get_data(
1419 struct libusb_transfer *transfer)
1421 return transfer->buffer + LIBUSB_CONTROL_SETUP_SIZE;
1424 /** \ingroup asyncio
1425 * Get the control setup packet of a control transfer. This convenience
1426 * function is here to remind you that the control setup occupies the first
1427 * 8 bytes of the transfer data buffer.
1429 * Calling this function only makes sense from a transfer callback function,
1430 * or situations where you have already allocated a suitably sized buffer at
1433 * \param transfer a transfer
1434 * \returns a casted pointer to the start of the transfer data buffer
1436 static inline struct libusb_control_setup *libusb_control_transfer_get_setup(
1437 struct libusb_transfer *transfer)
1439 return (struct libusb_control_setup *)(void *) transfer->buffer;
1442 /** \ingroup asyncio
1443 * Helper function to populate the setup packet (first 8 bytes of the data
1444 * buffer) for a control transfer. The wIndex, wValue and wLength values should
1445 * be given in host-endian byte order.
1447 * \param buffer buffer to output the setup packet into
1448 * This pointer must be aligned to at least 2 bytes boundary.
1449 * \param bmRequestType see the
1450 * \ref libusb_control_setup::bmRequestType "bmRequestType" field of
1451 * \ref libusb_control_setup
1452 * \param bRequest see the
1453 * \ref libusb_control_setup::bRequest "bRequest" field of
1454 * \ref libusb_control_setup
1455 * \param wValue see the
1456 * \ref libusb_control_setup::wValue "wValue" field of
1457 * \ref libusb_control_setup
1458 * \param wIndex see the
1459 * \ref libusb_control_setup::wIndex "wIndex" field of
1460 * \ref libusb_control_setup
1461 * \param wLength see the
1462 * \ref libusb_control_setup::wLength "wLength" field of
1463 * \ref libusb_control_setup
1465 static inline void libusb_fill_control_setup(unsigned char *buffer,
1466 uint8_t bmRequestType, uint8_t bRequest, uint16_t wValue, uint16_t wIndex,
1469 struct libusb_control_setup *setup = (struct libusb_control_setup *)(void *) buffer;
1470 setup->bmRequestType = bmRequestType;
1471 setup->bRequest = bRequest;
1472 setup->wValue = libusb_cpu_to_le16(wValue);
1473 setup->wIndex = libusb_cpu_to_le16(wIndex);
1474 setup->wLength = libusb_cpu_to_le16(wLength);
1477 struct libusb_transfer * LIBUSB_CALL libusb_alloc_transfer(int iso_packets);
1478 int LIBUSB_CALL libusb_submit_transfer(struct libusb_transfer *transfer);
1479 int LIBUSB_CALL libusb_cancel_transfer(struct libusb_transfer *transfer);
1480 void LIBUSB_CALL libusb_free_transfer(struct libusb_transfer *transfer);
1481 void LIBUSB_CALL libusb_transfer_set_stream_id(
1482 struct libusb_transfer *transfer, uint32_t stream_id);
1483 uint32_t LIBUSB_CALL libusb_transfer_get_stream_id(
1484 struct libusb_transfer *transfer);
1486 /** \ingroup asyncio
1487 * Helper function to populate the required \ref libusb_transfer fields
1488 * for a control transfer.
1490 * If you pass a transfer buffer to this function, the first 8 bytes will
1491 * be interpreted as a control setup packet, and the wLength field will be
1492 * used to automatically populate the \ref libusb_transfer::length "length"
1493 * field of the transfer. Therefore the recommended approach is:
1494 * -# Allocate a suitably sized data buffer (including space for control setup)
1495 * -# Call libusb_fill_control_setup()
1496 * -# If this is a host-to-device transfer with a data stage, put the data
1497 * in place after the setup packet
1498 * -# Call this function
1499 * -# Call libusb_submit_transfer()
1501 * It is also legal to pass a NULL buffer to this function, in which case this
1502 * function will not attempt to populate the length field. Remember that you
1503 * must then populate the buffer and length fields later.
1505 * \param transfer the transfer to populate
1506 * \param dev_handle handle of the device that will handle the transfer
1507 * \param buffer data buffer. If provided, this function will interpret the
1508 * first 8 bytes as a setup packet and infer the transfer length from that.
1509 * This pointer must be aligned to at least 2 bytes boundary.
1510 * \param callback callback function to be invoked on transfer completion
1511 * \param user_data user data to pass to callback function
1512 * \param timeout timeout for the transfer in milliseconds
1514 static inline void libusb_fill_control_transfer(
1515 struct libusb_transfer *transfer, libusb_device_handle *dev_handle,
1516 unsigned char *buffer, libusb_transfer_cb_fn callback, void *user_data,
1517 unsigned int timeout)
1519 struct libusb_control_setup *setup = (struct libusb_control_setup *)(void *) buffer;
1520 transfer->dev_handle = dev_handle;
1521 transfer->endpoint = 0;
1522 transfer->type = LIBUSB_TRANSFER_TYPE_CONTROL;
1523 transfer->timeout = timeout;
1524 transfer->buffer = buffer;
1526 transfer->length = (int) (LIBUSB_CONTROL_SETUP_SIZE
1527 + libusb_le16_to_cpu(setup->wLength));
1528 transfer->user_data = user_data;
1529 transfer->callback = callback;
1532 /** \ingroup asyncio
1533 * Helper function to populate the required \ref libusb_transfer fields
1534 * for a bulk transfer.
1536 * \param transfer the transfer to populate
1537 * \param dev_handle handle of the device that will handle the transfer
1538 * \param endpoint address of the endpoint where this transfer will be sent
1539 * \param buffer data buffer
1540 * \param length length of data buffer
1541 * \param callback callback function to be invoked on transfer completion
1542 * \param user_data user data to pass to callback function
1543 * \param timeout timeout for the transfer in milliseconds
1545 static inline void libusb_fill_bulk_transfer(struct libusb_transfer *transfer,
1546 libusb_device_handle *dev_handle, unsigned char endpoint,
1547 unsigned char *buffer, int length, libusb_transfer_cb_fn callback,
1548 void *user_data, unsigned int timeout)
1550 transfer->dev_handle = dev_handle;
1551 transfer->endpoint = endpoint;
1552 transfer->type = LIBUSB_TRANSFER_TYPE_BULK;
1553 transfer->timeout = timeout;
1554 transfer->buffer = buffer;
1555 transfer->length = length;
1556 transfer->user_data = user_data;
1557 transfer->callback = callback;
1560 /** \ingroup asyncio
1561 * Helper function to populate the required \ref libusb_transfer fields
1562 * for a bulk transfer using bulk streams.
1564 * Since version 1.0.19, \ref LIBUSB_API_VERSION >= 0x01000103
1566 * \param transfer the transfer to populate
1567 * \param dev_handle handle of the device that will handle the transfer
1568 * \param endpoint address of the endpoint where this transfer will be sent
1569 * \param stream_id bulk stream id for this transfer
1570 * \param buffer data buffer
1571 * \param length length of data buffer
1572 * \param callback callback function to be invoked on transfer completion
1573 * \param user_data user data to pass to callback function
1574 * \param timeout timeout for the transfer in milliseconds
1576 static inline void libusb_fill_bulk_stream_transfer(
1577 struct libusb_transfer *transfer, libusb_device_handle *dev_handle,
1578 unsigned char endpoint, uint32_t stream_id,
1579 unsigned char *buffer, int length, libusb_transfer_cb_fn callback,
1580 void *user_data, unsigned int timeout)
1582 libusb_fill_bulk_transfer(transfer, dev_handle, endpoint, buffer,
1583 length, callback, user_data, timeout);
1584 transfer->type = LIBUSB_TRANSFER_TYPE_BULK_STREAM;
1585 libusb_transfer_set_stream_id(transfer, stream_id);
1588 /** \ingroup asyncio
1589 * Helper function to populate the required \ref libusb_transfer fields
1590 * for an interrupt transfer.
1592 * \param transfer the transfer to populate
1593 * \param dev_handle handle of the device that will handle the transfer
1594 * \param endpoint address of the endpoint where this transfer will be sent
1595 * \param buffer data buffer
1596 * \param length length of data buffer
1597 * \param callback callback function to be invoked on transfer completion
1598 * \param user_data user data to pass to callback function
1599 * \param timeout timeout for the transfer in milliseconds
1601 static inline void libusb_fill_interrupt_transfer(
1602 struct libusb_transfer *transfer, libusb_device_handle *dev_handle,
1603 unsigned char endpoint, unsigned char *buffer, int length,
1604 libusb_transfer_cb_fn callback, void *user_data, unsigned int timeout)
1606 transfer->dev_handle = dev_handle;
1607 transfer->endpoint = endpoint;
1608 transfer->type = LIBUSB_TRANSFER_TYPE_INTERRUPT;
1609 transfer->timeout = timeout;
1610 transfer->buffer = buffer;
1611 transfer->length = length;
1612 transfer->user_data = user_data;
1613 transfer->callback = callback;
1616 /** \ingroup asyncio
1617 * Helper function to populate the required \ref libusb_transfer fields
1618 * for an isochronous transfer.
1620 * \param transfer the transfer to populate
1621 * \param dev_handle handle of the device that will handle the transfer
1622 * \param endpoint address of the endpoint where this transfer will be sent
1623 * \param buffer data buffer
1624 * \param length length of data buffer
1625 * \param num_iso_packets the number of isochronous packets
1626 * \param callback callback function to be invoked on transfer completion
1627 * \param user_data user data to pass to callback function
1628 * \param timeout timeout for the transfer in milliseconds
1630 static inline void libusb_fill_iso_transfer(struct libusb_transfer *transfer,
1631 libusb_device_handle *dev_handle, unsigned char endpoint,
1632 unsigned char *buffer, int length, int num_iso_packets,
1633 libusb_transfer_cb_fn callback, void *user_data, unsigned int timeout)
1635 transfer->dev_handle = dev_handle;
1636 transfer->endpoint = endpoint;
1637 transfer->type = LIBUSB_TRANSFER_TYPE_ISOCHRONOUS;
1638 transfer->timeout = timeout;
1639 transfer->buffer = buffer;
1640 transfer->length = length;
1641 transfer->num_iso_packets = num_iso_packets;
1642 transfer->user_data = user_data;
1643 transfer->callback = callback;
1646 /** \ingroup asyncio
1647 * Convenience function to set the length of all packets in an isochronous
1648 * transfer, based on the num_iso_packets field in the transfer structure.
1650 * \param transfer a transfer
1651 * \param length the length to set in each isochronous packet descriptor
1652 * \see libusb_get_max_packet_size()
1654 static inline void libusb_set_iso_packet_lengths(
1655 struct libusb_transfer *transfer, unsigned int length)
1658 for (i = 0; i < transfer->num_iso_packets; i++)
1659 transfer->iso_packet_desc[i].length = length;
1662 /** \ingroup asyncio
1663 * Convenience function to locate the position of an isochronous packet
1664 * within the buffer of an isochronous transfer.
1666 * This is a thorough function which loops through all preceding packets,
1667 * accumulating their lengths to find the position of the specified packet.
1668 * Typically you will assign equal lengths to each packet in the transfer,
1669 * and hence the above method is sub-optimal. You may wish to use
1670 * libusb_get_iso_packet_buffer_simple() instead.
1672 * \param transfer a transfer
1673 * \param packet the packet to return the address of
1674 * \returns the base address of the packet buffer inside the transfer buffer,
1675 * or NULL if the packet does not exist.
1676 * \see libusb_get_iso_packet_buffer_simple()
1678 static inline unsigned char *libusb_get_iso_packet_buffer(
1679 struct libusb_transfer *transfer, unsigned int packet)
1685 /* oops..slight bug in the API. packet is an unsigned int, but we use
1686 * signed integers almost everywhere else. range-check and convert to
1687 * signed to avoid compiler warnings. FIXME for libusb-2. */
1688 if (packet > INT_MAX)
1690 _packet = (int) packet;
1692 if (_packet >= transfer->num_iso_packets)
1695 for (i = 0; i < _packet; i++)
1696 offset += transfer->iso_packet_desc[i].length;
1698 return transfer->buffer + offset;
1701 /** \ingroup asyncio
1702 * Convenience function to locate the position of an isochronous packet
1703 * within the buffer of an isochronous transfer, for transfers where each
1704 * packet is of identical size.
1706 * This function relies on the assumption that every packet within the transfer
1707 * is of identical size to the first packet. Calculating the location of
1708 * the packet buffer is then just a simple calculation:
1709 * <tt>buffer + (packet_size * packet)</tt>
1711 * Do not use this function on transfers other than those that have identical
1712 * packet lengths for each packet.
1714 * \param transfer a transfer
1715 * \param packet the packet to return the address of
1716 * \returns the base address of the packet buffer inside the transfer buffer,
1717 * or NULL if the packet does not exist.
1718 * \see libusb_get_iso_packet_buffer()
1720 static inline unsigned char *libusb_get_iso_packet_buffer_simple(
1721 struct libusb_transfer *transfer, unsigned int packet)
1725 /* oops..slight bug in the API. packet is an unsigned int, but we use
1726 * signed integers almost everywhere else. range-check and convert to
1727 * signed to avoid compiler warnings. FIXME for libusb-2. */
1728 if (packet > INT_MAX)
1730 _packet = (int) packet;
1732 if (_packet >= transfer->num_iso_packets)
1735 return transfer->buffer + ((int) transfer->iso_packet_desc[0].length * _packet);
1740 int LIBUSB_CALL libusb_control_transfer(libusb_device_handle *dev_handle,
1741 uint8_t request_type, uint8_t bRequest, uint16_t wValue, uint16_t wIndex,
1742 unsigned char *data, uint16_t wLength, unsigned int timeout);
1744 int LIBUSB_CALL libusb_bulk_transfer(libusb_device_handle *dev_handle,
1745 unsigned char endpoint, unsigned char *data, int length,
1746 int *actual_length, unsigned int timeout);
1748 int LIBUSB_CALL libusb_interrupt_transfer(libusb_device_handle *dev_handle,
1749 unsigned char endpoint, unsigned char *data, int length,
1750 int *actual_length, unsigned int timeout);
1753 * Retrieve a descriptor from the default control pipe.
1754 * This is a convenience function which formulates the appropriate control
1755 * message to retrieve the descriptor.
1757 * \param dev a device handle
1758 * \param desc_type the descriptor type, see \ref libusb_descriptor_type
1759 * \param desc_index the index of the descriptor to retrieve
1760 * \param data output buffer for descriptor
1761 * \param length size of data buffer
1762 * \returns number of bytes returned in data, or LIBUSB_ERROR code on failure
1764 static inline int libusb_get_descriptor(libusb_device_handle *dev,
1765 uint8_t desc_type, uint8_t desc_index, unsigned char *data, int length)
1767 return libusb_control_transfer(dev, LIBUSB_ENDPOINT_IN,
1768 LIBUSB_REQUEST_GET_DESCRIPTOR, (uint16_t) ((desc_type << 8) | desc_index),
1769 0, data, (uint16_t) length, 1000);
1773 * Retrieve a descriptor from a device.
1774 * This is a convenience function which formulates the appropriate control
1775 * message to retrieve the descriptor. The string returned is Unicode, as
1776 * detailed in the USB specifications.
1778 * \param dev a device handle
1779 * \param desc_index the index of the descriptor to retrieve
1780 * \param langid the language ID for the string descriptor
1781 * \param data output buffer for descriptor
1782 * \param length size of data buffer
1783 * \returns number of bytes returned in data, or LIBUSB_ERROR code on failure
1784 * \see libusb_get_string_descriptor_ascii()
1786 static inline int libusb_get_string_descriptor(libusb_device_handle *dev,
1787 uint8_t desc_index, uint16_t langid, unsigned char *data, int length)
1789 return libusb_control_transfer(dev, LIBUSB_ENDPOINT_IN,
1790 LIBUSB_REQUEST_GET_DESCRIPTOR, (uint16_t)((LIBUSB_DT_STRING << 8) | desc_index),
1791 langid, data, (uint16_t) length, 1000);
1794 int LIBUSB_CALL libusb_get_string_descriptor_ascii(libusb_device_handle *dev,
1795 uint8_t desc_index, unsigned char *data, int length);
1797 /* polling and timeouts */
1799 int LIBUSB_CALL libusb_try_lock_events(libusb_context *ctx);
1800 void LIBUSB_CALL libusb_lock_events(libusb_context *ctx);
1801 void LIBUSB_CALL libusb_unlock_events(libusb_context *ctx);
1802 int LIBUSB_CALL libusb_event_handling_ok(libusb_context *ctx);
1803 int LIBUSB_CALL libusb_event_handler_active(libusb_context *ctx);
1804 void LIBUSB_CALL libusb_lock_event_waiters(libusb_context *ctx);
1805 void LIBUSB_CALL libusb_unlock_event_waiters(libusb_context *ctx);
1806 int LIBUSB_CALL libusb_wait_for_event(libusb_context *ctx, struct timeval *tv);
1808 int LIBUSB_CALL libusb_handle_events_timeout(libusb_context *ctx,
1809 struct timeval *tv);
1810 int LIBUSB_CALL libusb_handle_events_timeout_completed(libusb_context *ctx,
1811 struct timeval *tv, int *completed);
1812 int LIBUSB_CALL libusb_handle_events(libusb_context *ctx);
1813 int LIBUSB_CALL libusb_handle_events_completed(libusb_context *ctx, int *completed);
1814 int LIBUSB_CALL libusb_handle_events_locked(libusb_context *ctx,
1815 struct timeval *tv);
1816 int LIBUSB_CALL libusb_pollfds_handle_timeouts(libusb_context *ctx);
1817 int LIBUSB_CALL libusb_get_next_timeout(libusb_context *ctx,
1818 struct timeval *tv);
1821 * File descriptor for polling
1823 struct libusb_pollfd {
1824 /** Numeric file descriptor */
1827 /** Event flags to poll for from <poll.h>. POLLIN indicates that you
1828 * should monitor this file descriptor for becoming ready to read from,
1829 * and POLLOUT indicates that you should monitor this file descriptor for
1830 * nonblocking write readiness. */
1835 * Callback function, invoked when a new file descriptor should be added
1836 * to the set of file descriptors monitored for events.
1837 * \param fd the new file descriptor
1838 * \param events events to monitor for, see \ref libusb_pollfd for a
1840 * \param user_data User data pointer specified in
1841 * libusb_set_pollfd_notifiers() call
1842 * \see libusb_set_pollfd_notifiers()
1844 typedef void (LIBUSB_CALL *libusb_pollfd_added_cb)(int fd, short events,
1848 * Callback function, invoked when a file descriptor should be removed from
1849 * the set of file descriptors being monitored for events. After returning
1850 * from this callback, do not use that file descriptor again.
1851 * \param fd the file descriptor to stop monitoring
1852 * \param user_data User data pointer specified in
1853 * libusb_set_pollfd_notifiers() call
1854 * \see libusb_set_pollfd_notifiers()
1856 typedef void (LIBUSB_CALL *libusb_pollfd_removed_cb)(int fd, void *user_data);
1858 const struct libusb_pollfd ** LIBUSB_CALL libusb_get_pollfds(
1859 libusb_context *ctx);
1860 void LIBUSB_CALL libusb_free_pollfds(const struct libusb_pollfd **pollfds);
1861 void LIBUSB_CALL libusb_set_pollfd_notifiers(libusb_context *ctx,
1862 libusb_pollfd_added_cb added_cb, libusb_pollfd_removed_cb removed_cb,
1865 /** \ingroup hotplug
1868 * Callbacks handles are generated by libusb_hotplug_register_callback()
1869 * and can be used to deregister callbacks. Callback handles are unique
1870 * per libusb_context and it is safe to call libusb_hotplug_deregister_callback()
1871 * on an already deregisted callback.
1873 * Since version 1.0.16, \ref LIBUSB_API_VERSION >= 0x01000102
1875 * For more information, see \ref hotplug.
1877 typedef int libusb_hotplug_callback_handle;
1879 /** \ingroup hotplug
1881 * Since version 1.0.16, \ref LIBUSB_API_VERSION >= 0x01000102
1883 * Flags for hotplug events */
1885 /** Default value when not using any flags. */
1886 LIBUSB_HOTPLUG_NO_FLAGS = 0,
1888 /** Arm the callback and fire it for all matching currently attached devices. */
1889 LIBUSB_HOTPLUG_ENUMERATE = 1<<0,
1890 } libusb_hotplug_flag;
1892 /** \ingroup hotplug
1894 * Since version 1.0.16, \ref LIBUSB_API_VERSION >= 0x01000102
1898 /** A device has been plugged in and is ready to use */
1899 LIBUSB_HOTPLUG_EVENT_DEVICE_ARRIVED = 0x01,
1901 /** A device has left and is no longer available.
1902 * It is the user's responsibility to call libusb_close on any handle associated with a disconnected device.
1903 * It is safe to call libusb_get_device_descriptor on a device that has left */
1904 LIBUSB_HOTPLUG_EVENT_DEVICE_LEFT = 0x02,
1905 } libusb_hotplug_event;
1907 /** \ingroup hotplug
1908 * Wildcard matching for hotplug events */
1909 #define LIBUSB_HOTPLUG_MATCH_ANY -1
1911 /** \ingroup hotplug
1912 * Hotplug callback function type. When requesting hotplug event notifications,
1913 * you pass a pointer to a callback function of this type.
1915 * This callback may be called by an internal event thread and as such it is
1916 * recommended the callback do minimal processing before returning.
1918 * libusb will call this function later, when a matching event had happened on
1919 * a matching device. See \ref hotplug for more information.
1921 * It is safe to call either libusb_hotplug_register_callback() or
1922 * libusb_hotplug_deregister_callback() from within a callback function.
1924 * Since version 1.0.16, \ref LIBUSB_API_VERSION >= 0x01000102
1926 * \param ctx context of this notification
1927 * \param device libusb_device this event occurred on
1928 * \param event event that occurred
1929 * \param user_data user data provided when this callback was registered
1930 * \returns bool whether this callback is finished processing events.
1931 * returning 1 will cause this callback to be deregistered
1933 typedef int (LIBUSB_CALL *libusb_hotplug_callback_fn)(libusb_context *ctx,
1934 libusb_device *device,
1935 libusb_hotplug_event event,
1938 /** \ingroup hotplug
1939 * Register a hotplug callback function
1941 * Register a callback with the libusb_context. The callback will fire
1942 * when a matching event occurs on a matching device. The callback is
1943 * armed until either it is deregistered with libusb_hotplug_deregister_callback()
1944 * or the supplied callback returns 1 to indicate it is finished processing events.
1946 * If the \ref LIBUSB_HOTPLUG_ENUMERATE is passed the callback will be
1947 * called with a \ref LIBUSB_HOTPLUG_EVENT_DEVICE_ARRIVED for all devices
1948 * already plugged into the machine. Note that libusb modifies its internal
1949 * device list from a separate thread, while calling hotplug callbacks from
1950 * libusb_handle_events(), so it is possible for a device to already be present
1951 * on, or removed from, its internal device list, while the hotplug callbacks
1952 * still need to be dispatched. This means that when using \ref
1953 * LIBUSB_HOTPLUG_ENUMERATE, your callback may be called twice for the arrival
1954 * of the same device, once from libusb_hotplug_register_callback() and once
1955 * from libusb_handle_events(); and/or your callback may be called for the
1956 * removal of a device for which an arrived call was never made.
1958 * Since version 1.0.16, \ref LIBUSB_API_VERSION >= 0x01000102
1960 * \param[in] ctx context to register this callback with
1961 * \param[in] events bitwise or of events that will trigger this callback. See \ref
1962 * libusb_hotplug_event
1963 * \param[in] flags hotplug callback flags. See \ref libusb_hotplug_flag
1964 * \param[in] vendor_id the vendor id to match or \ref LIBUSB_HOTPLUG_MATCH_ANY
1965 * \param[in] product_id the product id to match or \ref LIBUSB_HOTPLUG_MATCH_ANY
1966 * \param[in] dev_class the device class to match or \ref LIBUSB_HOTPLUG_MATCH_ANY
1967 * \param[in] cb_fn the function to be invoked on a matching event/device
1968 * \param[in] user_data user data to pass to the callback function
1969 * \param[out] handle pointer to store the handle of the allocated callback (can be NULL)
1970 * \returns LIBUSB_SUCCESS on success LIBUSB_ERROR code on failure
1972 int LIBUSB_CALL libusb_hotplug_register_callback(libusb_context *ctx,
1973 libusb_hotplug_event events,
1974 libusb_hotplug_flag flags,
1975 int vendor_id, int product_id,
1977 libusb_hotplug_callback_fn cb_fn,
1979 libusb_hotplug_callback_handle *handle);
1981 /** \ingroup hotplug
1982 * Deregisters a hotplug callback.
1984 * Deregister a callback from a libusb_context. This function is safe to call from within
1985 * a hotplug callback.
1987 * Since version 1.0.16, \ref LIBUSB_API_VERSION >= 0x01000102
1989 * \param[in] ctx context this callback is registered with
1990 * \param[in] handle the handle of the callback to deregister
1992 void LIBUSB_CALL libusb_hotplug_deregister_callback(libusb_context *ctx,
1993 libusb_hotplug_callback_handle handle);