1.\" 2.\" Copyright (c) 2008 Hans Petter Selasky 3.\" 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" $FreeBSD$ 28.\" 29.Dd November 18, 2009 30.Dt LIBUSB20 3 31.Os 32.Sh NAME 33.Nm libusb20 34. 35.Nd "USB access library" 36. 37. 38.Sh LIBRARY 39. 40. 41USB access library (libusb -lusb) 42. 43. 44. 45.Sh SYNOPSIS 46.In libusb20.h 47.Ft int 48.Fn libusb20_tr_close "struct libusb20_transfer *xfer" 49.Ft int 50.Fn libusb20_tr_open "struct libusb20_transfer *xfer" "uint32_t max_buf_size" "uint32_t max_frame_count" "uint8_t ep_no" 51.Ft struct libusb20_transfer* 52.Fn libusb20_tr_get_pointer "struct libusb20_device *pdev" "uint16_t tr_index" 53.Ft uint16_t 54.Fn libusb20_tr_get_time_complete "struct libusb20_transfer *xfer" 55.Ft uint32_t 56.Fn libusb20_tr_get_actual_frames "struct libusb20_transfer *xfer" 57.Ft uint32_t 58.Fn libusb20_tr_get_actual_length "struct libusb20_transfer *xfer" 59.Ft uint32_t 60.Fn libusb20_tr_get_max_frames "struct libusb20_transfer *xfer" 61.Ft uint32_t 62.Fn libusb20_tr_get_max_packet_length "struct libusb20_transfer *xfer" 63.Ft uint32_t 64.Fn libusb20_tr_get_max_total_length "struct libusb20_transfer *xfer" 65.Ft uint8_t 66.Fn libusb20_tr_get_status "struct libusb20_transfer *xfer" 67.Ft uint8_t 68.Fn libusb20_tr_pending "struct libusb20_transfer *xfer" 69.Ft void 70.Fn libusb20_tr_callback_wrapper "struct libusb20_transfer *xfer" 71.Ft void 72.Fn libusb20_tr_clear_stall_sync "struct libusb20_transfer *xfer" 73.Ft void 74.Fn libusb20_tr_drain "struct libusb20_transfer *xfer" 75.Ft void 76.Fn libusb20_tr_set_buffer "struct libusb20_transfer *xfer" "void *buffer" "uint16_t fr_index" 77.Ft void 78.Fn libusb20_tr_set_callback "struct libusb20_transfer *xfer" "libusb20_tr_callback_t *cb" 79.Ft void 80.Fn libusb20_tr_set_flags "struct libusb20_transfer *xfer" "uint8_t flags" 81.Ft uint32_t 82.Fn libusb20_tr_get_length "struct libusb20_transfer *xfer" "uint16_t fr_index" 83.Ft void 84.Fn libusb20_tr_set_length "struct libusb20_transfer *xfer" "uint32_t length" "uint16_t fr_index" 85.Ft void 86.Fn libusb20_tr_set_priv_sc0 "struct libusb20_transfer *xfer" "void *sc0" 87.Ft void 88.Fn libusb20_tr_set_priv_sc1 "struct libusb20_transfer *xfer" "void *sc1" 89.Ft void 90.Fn libusb20_tr_set_timeout "struct libusb20_transfer *xfer" "uint32_t timeout" 91.Ft void 92.Fn libusb20_tr_set_total_frames "struct libusb20_transfer *xfer" "uint32_t nframes" 93.Ft void 94.Fn libusb20_tr_setup_bulk "struct libusb20_transfer *xfer" "void *pbuf" "uint32_t length" "uint32_t timeout" 95.Ft void 96.Fn libusb20_tr_setup_control "struct libusb20_transfer *xfer" "void *psetup" "void *pbuf" "uint32_t timeout" 97.Ft void 98.Fn libusb20_tr_setup_intr "struct libusb20_transfer *xfer" "void *pbuf" "uint32_t length" "uint32_t timeout" 99.Ft void 100.Fn libusb20_tr_setup_isoc "struct libusb20_transfer *xfer" "void *pbuf" "uint32_t length" "uint61_t fr_index" 101.Ft uint8_t 102.Fn libusb20_tr_bulk_intr_sync "struct libusb20_transfer *xfer" "void *pbuf" "uint32_t length" "uint32_t *pactlen" "uint32_t timeout" 103.Ft void 104.Fn libusb20_tr_start "struct libusb20_transfer *xfer" 105.Ft void 106.Fn libusb20_tr_stop "struct libusb20_transfer *xfer" 107.Ft void 108.Fn libusb20_tr_submit "struct libusb20_transfer *xfer" 109.Ft void * 110.Fn libusb20_tr_get_priv_sc0 "struct libusb20_transfer *xfer" 111.Ft void * 112.Fn libusb20_tr_get_priv_sc1 "struct libusb20_transfer *xfer" 113.Ft const char * 114.Fn libusb20_dev_get_backend_name "struct libusb20_device *" 115.Ft int 116.Fn libusb20_dev_get_info "struct libusb20_device *pdev" "struct usb_device_info *pinfo" 117.Ft int 118.Fn libusb20_dev_get_iface_desc "struct libusb20_device *pdev" "uint8_t iface_index" "char *buf" "uint8_t len" 119.Ft const char * 120.Fn libusb20_dev_get_desc "struct libusb20_device *pdev" 121.Ft int 122.Fn libusb20_dev_close "struct libusb20_device *pdev" 123.Ft int 124.Fn libusb20_dev_detach_kernel_driver "struct libusb20_device *pdev" "uint8_t iface_index" 125.Ft int 126.Fn libusb20_dev_set_config_index "struct libusb20_device *pdev" "uint8_t configIndex" 127.Ft int 128.Fn libusb20_dev_get_debug "struct libusb20_device *pdev" 129.Ft int 130.Fn libusb20_dev_get_fd "struct libusb20_device *pdev" 131.Ft int 132.Fn libusb20_dev_kernel_driver_active "struct libusb20_device *pdev" "uint8_t iface_index" 133.Ft int 134.Fn libusb20_dev_open "struct libusb20_device *pdev" "uint16_t transfer_max" 135.Ft int 136.Fn libusb20_dev_process "struct libusb20_device *pdev" 137.Ft int 138.Fn libusb20_dev_request_sync "struct libusb20_device *pdev" "struct LIBUSB20_CONTROL_SETUP_DECODED *setup" "void *data" "uint16_t *pactlen" "uint32_t timeout" "uint8_t flags" 139.Ft int 140.Fn libusb20_dev_req_string_sync "struct libusb20_device *pdev" "uint8_t index" "uint16_t langid" "void *ptr" "uint16_t len" 141.Ft int 142.Fn libusb20_dev_req_string_simple_sync "struct libusb20_device *pdev" "uint8_t index" "void *ptr" "uint16_t len" 143.Ft int 144.Fn libusb20_dev_reset "struct libusb20_device *pdev" 145.Ft int 146.Fn libusb20_dev_check_connected "struct libusb20_device *pdev" 147.Ft int 148.Fn libusb20_dev_set_power_mode "struct libusb20_device *pdev" "uint8_t power_mode" 149.Ft uint8_t 150.Fn libusb20_dev_get_power_mode "struct libusb20_device *pdev" 151.Ft int 152.Fn libusb20_dev_set_alt_index "struct libusb20_device *pdev" "uint8_t iface_index" "uint8_t alt_index" 153.Ft struct LIBUSB20_DEVICE_DESC_DECODED * 154.Fn libusb20_dev_get_device_desc "struct libusb20_device *pdev" 155.Ft struct libusb20_config * 156.Fn libusb20_dev_alloc_config "struct libusb20_device *pdev" "uint8_t config_index" 157.Ft struct libusb20_device * 158.Fn libusb20_dev_alloc "void" 159.Ft uint8_t 160.Fn libusb20_dev_get_address "struct libusb20_device *pdev" 161.Ft uint8_t 162.Fn libusb20_dev_get_bus_number "struct libusb20_device *pdev" 163.Ft uint8_t 164.Fn libusb20_dev_get_mode "struct libusb20_device *pdev" 165.Ft uint8_t 166.Fn libusb20_dev_get_speed "struct libusb20_device *pdev" 167.Ft uint8_t 168.Fn libusb20_dev_get_config_index "struct libusb20_device *pdev" 169.Ft void 170.Fn libusb20_dev_free "struct libusb20_device *pdev" 171.Ft void 172.Fn libusb20_dev_set_debug "struct libusb20_device *pdev" "int debug" 173.Ft void 174.Fn libusb20_dev_wait_process "struct libusb20_device *pdev" "int timeout" 175.Ft int 176.Fn libusb20_be_get_template "struct libusb20_backend *pbe" "int *ptemp" 177.Ft int 178.Fn libusb20_be_set_template "struct libusb20_backend *pbe" "int temp" 179.Ft int 180.Fn libusb20_be_get_dev_quirk "struct libusb20_backend *pber", "uint16_t index" "struct libusb20_quirk *pq" 181.Ft int 182.Fn libusb20_be_get_quirk_name "struct libusb20_backend *pbe" "uint16_t index" "struct libusb20_quirk *pq" 183.Ft int 184.Fn libusb20_be_add_dev_quirk "struct libusb20_backend *pbe" "struct libusb20_quirk *pq" 185.Ft int 186.Fn libusb20_be_remove_dev_quirk "struct libusb20_backend *pbe" "struct libusb20_quirk *pq" 187.Ft struct libusb20_backend * 188.Fn libusb20_be_alloc_default "void" 189.Ft struct libusb20_backend * 190.Fn libusb20_be_alloc_freebsd "void" 191.Ft struct libusb20_backend * 192.Fn libusb20_be_alloc_linux "void" 193.Ft struct libusb20_device * 194.Fn libusb20_be_device_foreach "struct libusb20_backend *pbe" "struct libusb20_device *pdev" 195.Ft void 196.Fn libusb20_be_dequeue_device "struct libusb20_backend *pbe" "struct libusb20_device *pdev" 197.Ft void 198.Fn libusb20_be_enqueue_device "struct libusb20_backend *pbe" "struct libusb20_device *pdev" 199.Ft void 200.Fn libusb20_be_free "struct libusb20_backend *pbe" 201.Ft uint8_t 202.Fn libusb20_me_get_1 "const struct libusb20_me_struct *me" "uint16_t off" 203.Ft uint16_t 204.Fn libusb20_me_get_2 "const struct libusb20_me_struct *me" "uint16_t off" 205.Ft uint16_t 206.Fn libusb20_me_encode "void *pdata" "uint16_t len" "const void *pdecoded" 207.Ft uint16_t 208.Fn libusb20_me_decode "const void *pdata" "uint16_t len" "void *pdecoded" 209.Ft "const uint8_t *" 210.Fn libusb20_desc_foreach "const struct libusb20_me_struct *me" "const uint8_t *pdesc" 211. 212. 213.Sh DESCRIPTION 214. 215The 216.Nm 217library implements functions to be able to easily access and control 218USB through the USB file system interface. 219The 220.Nm 221interfaces are specific to the 222.Fx 223usb stack and are not available on other operating systems, portable 224applications should consider using 225.Xr libusb 3 . 226. 227. 228.Sh USB TRANSFER OPERATIONS 229. 230.Pp 231. 232.Fn libusb20_tr_close 233will release all kernel resources associated with an USB 234.Fa xfer . 235. 236This function returns zero upon success. 237. 238Non-zero return values indicate a LIBUSB20_ERROR value. 239. 240.Pp 241. 242.Fn libusb20_tr_open 243will allocate kernel buffer resources according to 244.Fa max_buf_size 245and 246.Fa max_frame_count 247associated with an USB 248.Fa pxfer 249and bind the transfer to the specified 250.Fa ep_no . 251.Fa max_buf_size 252is the minimum buffer size which the data transport layer has to support. 253If 254.Fa max_buf_size 255is zero, the 256.Nm 257library will use wMaxPacketSize to compute the buffer size. 258This can be useful for isochronous transfers. 259The actual buffer size can be greater than 260.Fa max_buf_size 261and is returned by 262.Fn libusb20_tr_get_max_total_length . 263. 264This function returns zero upon success. 265. 266Non-zero return values indicate a LIBUSB20_ERROR value. 267. 268.Pp 269. 270.Fn libusb20_tr_get_pointer 271will return a pointer to the allocated USB transfer according to the 272.Fa pdev 273and 274.Fa tr_index 275arguments. 276. 277This function returns NULL in case of failure. 278. 279.Pp 280. 281.Fn libusb20_tr_get_time_complete 282will return the completion time of an USB transfer in 283millisecond units. This function is most useful for isochronous USB 284transfers when doing echo cancelling. 285. 286.Pp 287. 288.Fn libusb20_tr_get_actual_frames 289will return the actual number of USB frames after an USB 290transfer completed. A value of zero means that no data was transferred. 291. 292.Pp 293. 294.Fn libusb20_tr_get_actual_length 295will return the sum of the actual length for all 296transferred USB frames for the given USB transfer. 297. 298.Pp 299. 300.Fn libusb20_tr_get_max_frames 301will return the maximum number of USB frames that were 302allocated when an USB transfer was setup for the given USB transfer. 303. 304.Pp 305. 306.Fn libusb20_tr_get_max_packet_length 307will return the maximum packet length in bytes 308associated with the given USB transfer. 309. 310The packet length can be used round up buffer sizes so that short USB 311packets are avoided for proxy buffers. 312. 313. 314.Pp 315. 316.Fn libusb20_tr_get_max_total_length 317function will return the maximum value for the data length sum of all USB 318frames associated with an USB transfer. 319In case of control transfers the value returned does not include the 320length of the SETUP packet, 8 bytes, which is part of frame zero. 321The returned value of this function is always aligned to the maximum 322packet size, wMaxPacketSize, of the endpoint which the USB transfer is 323bound to. 324. 325.Pp 326. 327.Fn libusb20_tr_get_status 328will return the status of an USB transfer. 329. 330Status values are defined by a set of LIBUSB20_TRANSFER_XXX enums. 331. 332.Pp 333. 334.Fn libusb20_tr_pending 335will return non-zero if the given USB transfer is 336pending for completion. 337. 338Else this function returns zero. 339. 340.Pp 341. 342.Fn libusb20_tr_callback_wrapper 343This is an internal function used to wrap asynchronous USB callbacks. 344. 345.Pp 346. 347.Fn libusb20_tr_clear_stall_sync 348This is an internal function used to synchronously clear the stall on 349the given USB transfer. 350. 351Please see the USB specification for more information on stall 352clearing. 353. 354If the given USB transfer is pending when this function is called, the 355USB transfer will complete with an error after that this function has 356been called. 357. 358.Pp 359. 360.Fn libusb20_tr_drain 361will stop the given USB transfer and will not return 362until the USB transfer has been stopped in hardware. 363. 364.Pp 365. 366.Fn libusb20_tr_set_buffer 367is used to set the 368.Fa buffer 369pointer for the given USB transfer and 370.Fa fr_index . 371. 372Typically the frame index is zero. 373. 374. 375.Pp 376. 377.Fn libusb20_tr_set_callback 378is used to set the USB callback for asynchronous USB 379transfers. 380. 381The callback type is defined by libusb20_tr_callback_t. 382. 383.Pp 384. 385.Fn libusb20_tr_set_flags 386is used to set various USB flags for the given USB transfer. 387.Bl -tag 388.It LIBUSB20_TRANSFER_SINGLE_SHORT_NOT_OK 389Report a short frame as error. 390.It LIBUSB20_TRANSFER_MULTI_SHORT_NOT_OK 391Multiple short frames are not allowed. 392.It LIBUSB20_TRANSFER_FORCE_SHORT 393All transmitted frames are short terminated. 394.It LIBUSB20_TRANSFER_DO_CLEAR_STALL 395Will do a clear-stall before starting the transfer. 396.El 397. 398.Pp 399. 400.Fn libusb20_tr_get_length 401returns the length of the given USB frame by index. 402After an USB transfer is complete the USB frame length will get updated to the actual transferred length. 403. 404.Pp 405. 406.Fn libusb20_tr_set_length 407sets the length of the given USB frame by index. 408. 409.Pp 410. 411.Fn libusb20_tr_set_priv_sc0 412sets private driver pointer number zero. 413. 414.Pp 415. 416.Fn libusb20_tr_set_priv_sc1 417sets private driver pointer number one. 418. 419.Pp 420. 421.Fn libusb20_tr_set_timeout 422sets the timeout for the given USB transfer. 423. 424A timeout value of zero means no timeout. 425. 426The timeout is given in milliseconds. 427. 428.Pp 429. 430.Fn libusb20_tr_set_total_frames 431sets the total number of frames that should be executed when the USB transfer is submitted. 432. 433The total number of USB frames must be less than the maximum number of USB frames associated with the given USB transfer. 434. 435.Pp 436. 437.Fn libusb20_tr_setup_bulk 438is a helper function for setting up a single frame USB BULK transfer. 439. 440.Pp 441. 442.Fn libusb20_tr_setup_control 443is a helper function for setting up a single or dual 444frame USB CONTROL transfer depending on the control transfer length. 445. 446.Pp 447. 448.Fn libusb20_tr_setup_intr 449is a helper function for setting up a single frame USB INTERRUPT transfer. 450. 451.Pp 452. 453.Fn libusb20_tr_setup_isoc 454is a helper function for setting up a multi frame USB ISOCHRONOUS transfer. 455. 456.Pp 457. 458.Fn libusb20_tr_bulk_intr_sync 459will perform a synchronous BULK or INTERRUPT transfer having length given by the 460.Fa length 461argument and buffer pointer given by the 462.Fa pbuf 463argument on the USB transfer given by the 464.Fa xfer 465argument. 466. 467If the 468.Fa pactlen 469argument is non-NULL the actual transfer length will be stored at the given pointer destination. 470. 471If the 472.Fa timeout 473argument is non-zero the transfer will timeout after the given value in milliseconds. 474. 475This function does not change the transfer flags, like short packet not ok. 476. 477This function returns zero on success else a LIBUSB20_TRANSFER_XXX value is returned. 478. 479.Pp 480. 481.Fn libusb20_tr_start 482will get the USB transfer started, if not already 483started. 484. 485This function will not get the transfer queued in hardware. 486. 487This function is non-blocking. 488. 489.Pp 490. 491.Fn libusb20_tr_stop 492will get the USB transfer stopped, if not already stopped. 493. 494This function is non-blocking, which means that the actual stop can 495happen after the return of this function. 496. 497.Pp 498. 499.Fn libusb20_tr_submit 500will get the USB transfer queued in hardware. 501. 502. 503.Pp 504. 505.Fn libusb20_tr_get_priv_sc0 506returns private driver pointer number zero associated 507with an USB transfer. 508. 509. 510.Pp 511. 512.Fn libusb20_tr_get_priv_sc1 513returns private driver pointer number one associated 514with an USB transfer. 515. 516. 517.Sh USB DEVICE OPERATIONS 518. 519.Pp 520. 521.Fn libusb20_dev_get_backend_name 522returns a zero terminated string describing the backend used. 523. 524.Pp 525. 526.Fn libusb20_dev_get_info 527retrieves the BSD specific usb_device_info structure into the memory location given by 528.Fa pinfo . 529The USB device given by 530.Fa pdev 531must be opened before this function will succeed. 532This function returns zero on success else a LIBUSB20_ERROR value is returned. 533. 534.Pp 535. 536.Fn libusb20_dev_get_iface_desc 537retrieves the kernel interface description for the given USB 538.Fa iface_index . 539The format of the USB interface description is: "drivername<unit>: <description>" 540The description string is always zero terminated. 541A zero length string is written in case no driver is attached to the given interface. 542The USB device given by 543.Fa pdev 544must be opened before this function will succeed. 545This function returns zero on success else a LIBUSB20_ERROR value is returned. 546. 547.Pp 548. 549.Fn libusb20_dev_get_desc 550returns a zero terminated string describing the given USB device. 551The format of the string is: "drivername<unit>: <description>" 552. 553.Pp 554. 555.Fn libusb20_dev_close 556will close the given USB device. 557. 558This function returns zero on success else a LIBUSB20_ERROR value is 559returned. 560. 561.Pp 562. 563.Fn libusb20_dev_detach_kernel_driver 564will try to detach the kernel driver for the USB interface given by 565.Fa iface_index . 566. 567This function returns zero on success else a LIBUSB20_ERROR value is 568returned. 569. 570.Pp 571. 572.Fn libusb20_dev_set_config_index 573will try to set the configuration index on an USB 574device. 575. 576The first configuration index is zero. 577. 578The un-configure index is 255. 579. 580This function returns zero on success else a LIBUSB20_ERROR value is returned. 581. 582.Pp 583. 584.Fn libusb20_dev_get_debug 585returns the debug level of an USB device. 586. 587.Pp 588. 589.Fn libusb20_dev_get_fd 590returns the file descriptor of the given USB device. 591. 592A negative value is returned when no file descriptor is present. 593. 594The file descriptor can be used for polling purposes. 595. 596.Pp 597. 598.Fn libusb20_dev_kernel_driver_active 599returns a non-zero value if a kernel driver is active on 600the given USB interface. 601. 602Else zero is returned. 603. 604.Pp 605. 606.Fn libusb20_dev_open 607opens an USB device so that setting up USB transfers 608becomes possible. 609. 610The number of USB transfers can be zero which means only control 611transfers are allowed. 612. 613This function returns zero on success else a LIBUSB20_ERROR value is 614returned. 615. 616A return value of LIBUSB20_ERROR_BUSY means that the device is already 617opened. 618. 619.Pp 620. 621.Fn libusb20_dev_process 622is called to sync kernel USB transfers with userland USB 623transfers. 624. 625This function returns zero on success else a LIBUSB20_ERROR value is 626returned typically indicating that the given USB device has been 627detached. 628. 629.Pp 630. 631.Fn libusb20_dev_request_sync 632will perform a synchronous control request on the given 633USB device. 634. 635Before this call will succeed the USB device must be opened. 636. 637.Fa setup 638is a pointer to a decoded and host endian SETUP packet. 639.Fa data 640is a pointer to a data transfer buffer associated with the control transaction. This argument can be NULL. 641.Fa pactlen 642is a pointer to a variable that will hold the actual transfer length after the control transaction is complete. 643.Fa timeout 644is the transaction timeout given in milliseconds. 645A timeout of zero means no timeout. 646.Fa flags 647is used to specify transaction flags, for example LIBUSB20_TRANSFER_SINGLE_SHORT_NOT_OK. 648. 649This function returns zero on success else a LIBUSB20_ERROR value is 650returned. 651. 652.Pp 653. 654.Fn libusb20_dev_req_string_sync 655will synchronously request an USB string by language ID 656and string index into the given buffer limited by a maximum length. 657. 658This function returns zero on success else a LIBUSB20_ERROR value is 659returned. 660. 661.Pp 662. 663.Fn libusb20_dev_req_string_simple_sync 664will synchronously request an USB string using the 665default language ID and convert the string into ASCII before storing 666the string into the given buffer limited by a maximum length which 667includes the terminating zero. 668. 669This function returns zero on success else a LIBUSB20_ERROR value is 670returned. 671. 672. 673.Pp 674. 675.Fn libusb20_dev_reset 676will try to BUS reset the given USB device and restore 677the last set USB configuration. 678. 679This function returns zero on success else a LIBUSB20_ERROR value is 680returned. 681. 682. 683.Pp 684. 685.Fn libusb20_dev_check_connected 686will check if an opened USB device is still connected. 687. 688This function returns zero if the device is still connected else a LIBUSB20_ERROR value is returned. 689. 690. 691.Pp 692. 693.Fn libusb20_dev_set_power_mode 694sets the power mode of the USB device. 695. 696Valid power modes: 697.Bl -tag 698.It LIBUSB20_POWER_OFF 699.It LIBUSB20_POWER_ON 700.It LIBUSB20_POWER_SAVE 701.It LIBUSB20_POWER_SUSPEND 702.It LIBUSB20_POWER_RESUME 703.El 704. 705This function returns zero on success else a LIBUSB20_ERROR value is 706returned. 707. 708.Pp 709. 710.Fn libusb20_dev_get_power_mode 711returns the currently selected power mode for the given 712USB device. 713. 714.Pp 715. 716.Fn libusb20_dev_set_alt_index 717will try to set the given alternate index for the given 718USB interface index. 719. 720This function returns zero on success else a LIBUSB20_ERROR value is 721returned. 722. 723.Pp 724. 725.Fn libusb20_dev_get_device_desc 726returns a pointer to the decoded and host endian version 727of the device descriptor. 728. 729The USB device need not be opened when calling this function. 730. 731.Pp 732. 733.Fn libusb20_dev_alloc_config 734will read out and decode the USB config descriptor for 735the given USB device and config index. This function returns a pointer 736to the decoded configuration which must eventually be passed to 737free(). NULL is returned in case of failure. 738. 739.Pp 740. 741.Fn libusb20_dev_alloc 742is an internal function to allocate a new USB device. 743. 744.Pp 745. 746.Fn libusb20_dev_get_address 747returns the internal and not necessarily the real 748hardware address of the given USB device. 749. 750.Pp 751. 752.Fn libusb20_dev_get_bus_number 753returns the internal bus number which the given USB 754device belongs to. 755. 756.Pp 757. 758.Fn libusb20_dev_get_mode 759returns the current operation mode of the USB entity. 760. 761Valid return values are: 762.Bl -tag 763.It LIBUSB20_MODE_HOST 764.It LIBUSB20_MODE_DEVICE 765.El 766. 767.Pp 768. 769.Fn libusb20_dev_get_speed 770returns the current speed of the given USB device. 771. 772.Bl -tag 773.It LIBUSB20_SPEED_UNKNOWN 774.It LIBUSB20_SPEED_LOW 775.It LIBUSB20_SPEED_FULL 776.It LIBUSB20_SPEED_HIGH 777.It LIBUSB20_SPEED_VARIABLE 778.It LIBUSB20_SPEED_SUPER 779.El 780. 781.Pp 782. 783.Fn libusb20_dev_get_config_index 784This function returns the currently select config index for the given 785USB device. 786. 787.Pp 788. 789.Fn libusb20_dev_free 790will free the given USB device and all associated USB 791transfers. 792. 793.Pp 794. 795.Fn libusb20_dev_set_debug 796will set the debug level for the given USB device. 797. 798.Pp 799. 800.Fn libusb20_dev_wait_process 801function will wait until a pending USB transfer has completed on 802the given USB device. 803. 804A timeout value can be specified which is passed on to the 805.Xr poll 2 806function. 807. 808.Sh USB BACKEND OPERATIONS 809. 810.Fn libusb20_be_get_template 811will return the currently selected global USB device 812side mode template into the integer pointer 813.Fa ptemp . 814This function returns zero on success else a LIBUSB20_ERROR value is 815returned. 816. 817.Pp 818. 819.Fn libusb20_be_set_template 820will set the global USB device side mode template to 821.Fa temp . 822The new template is not activated until after the next USB 823enumeration. 824The template number decides how the USB device will present itself to 825the USB Host, like Mass Storage Device, USB Ethernet Device. Also see 826the 827.Xr usb2_template 4 828module. 829This function returns zero on success else a LIBUSB20_ERROR value is 830returned. 831. 832.Pp 833. 834.Fn libusb20_be_get_dev_quirk 835This function will return the device quirk according to 836.Fa index 837into the libusb20_quirk structure pointed to by 838.Fa pq . 839This function returns zero on success else a LIBUSB20_ERROR value is 840returned. 841. 842If the given quirk does not exist LIBUSB20_ERROR_NOT_FOUND is 843returned. 844. 845.Pp 846. 847.Fn libusb20_be_get_quirk_name 848will return the quirk name according to 849.Fa index 850into the libusb20_quirk structure pointed to by 851.Fa pq . 852This function returns zero on success else a LIBUSB20_ERROR value is 853returned. 854. 855If the given quirk does not exist LIBUSB20_ERROR_NOT_FOUND is 856returned. 857. 858.Pp 859. 860.Fn libusb20_be_add_dev_quirk 861will add the libusb20_quirk structure pointed to by the 862.Fa pq 863argument into the device quirk list. 864. 865This function returns zero on success else a LIBUSB20_ERROR value is 866returned. 867. 868If the given quirk cannot be added LIBUSB20_ERROR_NO_MEM is 869returned. 870. 871.Pp 872. 873.Fn libusb20_be_remove_dev_quirk 874will remove the quirk matching the libusb20_quirk structure pointed to by the 875.Fa pq 876argument from the device quirk list. 877. 878This function returns zero on success else a LIBUSB20_ERROR value is 879returned. 880. 881If the given quirk does not exist LIBUSB20_ERROR_NOT_FOUND is 882returned. 883. 884.Pp 885. 886.Fn libusb20_be_alloc_default 887.Fn libusb20_be_alloc_freebsd 888.Fn libusb20_be_alloc_linux 889These functions are used to allocate a specific USB backend or the 890operating system default USB backend. Allocating a backend is a way to 891scan for currently present USB devices. 892. 893.Pp 894. 895.Fn libusb20_be_device_foreach 896is used to iterate USB devices present in a USB backend. 897. 898The starting value of 899.Fa pdev 900is NULL. 901. 902This function returns the next USB device in the list. 903. 904If NULL is returned the end of the USB device list has been reached. 905. 906.Pp 907. 908.Fn libusb20_be_dequeue_device 909will dequeue the given USB device pointer from the 910backend USB device list. 911. 912Dequeued USB devices will not be freed when the backend is freed. 913. 914.Pp 915. 916.Fn libusb20_be_enqueue_device 917This function will enqueue the given USB device pointer in the backend USB device list. 918. 919Enqueued USB devices will get freed when the backend is freed. 920. 921.Pp 922. 923.Fn libusb20_be_free 924will free the given backend and all USB devices in its device list. 925. 926. 927.Sh USB DESCRIPTOR PARSING 928. 929.Fn libusb20_me_get_1 pie offset 930This function will return a byte at the given byte offset of a message 931entity. 932. 933This function is safe against invalid offsets. 934. 935.Pp 936. 937.Fn libusb20_me_get_2 pie offset 938This function will return a little endian 16-bit value at the given byte offset of a message 939entity. 940. 941This function is safe against invalid offsets. 942. 943.Pp 944. 945.Fn libusb20_me_encode pbuf len pdecoded 946This function will encode a so-called *DECODED structure into binary 947format. 948. 949The total encoded length that will fit in the given buffer is 950returned. 951. 952If the buffer pointer is NULL no data will be written to the buffer 953location. 954. 955.Pp 956. 957.Fn libusb20_me_decode pbuf len pdecoded 958This function will decode a binary structure into a so-called *DECODED 959structure. 960. 961The total decoded length is returned. 962. 963The buffer pointer cannot be NULL. 964. 965. 966.Sh FILES 967. 968. 969/dev/usb 970.Sh SEE ALSO 971.Xr usb 4 , 972.Xr libusb 3 , 973.Xr usbconfig 8 974. 975. 976.Sh HISTORY 977. 978. 979Some parts of the 980.Nm 981API derives from the libusb project at sourceforge. 982