1.\" $OpenBSD: usb.4,v 1.192 2019/03/27 22:11:21 kettenis Exp $ 2.\" $NetBSD: usb.4,v 1.15 1999/07/29 14:20:32 augustss Exp $ 3.\" 4.\" Copyright (c) 1999 The NetBSD Foundation, Inc. 5.\" All rights reserved. 6.\" 7.\" This code is derived from software contributed to The NetBSD Foundation 8.\" by Lennart Augustsson. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29.\" POSSIBILITY OF SUCH DAMAGE. 30.\" 31.Dd $Mdocdate: March 27 2019 $ 32.Dt USB 4 33.Os 34.Sh NAME 35.Nm usb , 36.Nm uhub 37.Nd introduction to Universal Serial Bus support 38.Sh SYNOPSIS 39.Cd "# octeon specific" 40.Cd "dwctwo0 at iobus? irq 56" 41.Cd "# all architectures" 42.Cd "ehci* at cardbus?" 43.Cd "ohci* at cardbus?" 44.Cd "uhci* at cardbus?" 45.Cd "ehci* at pci?" 46.Cd "ohci* at pci?" 47.Cd "uhci* at pci?" 48.Cd "xhci* at pci?" 49.Cd "usb* at dwctwo?" 50.Cd "usb* at ehci? flags 0x00" 51.Cd "usb* at ohci? flags 0x00" 52.Cd "usb* at uhci? flags 0x00" 53.Cd "usb* at xhci? flags 0x00" 54.Cd "uhub* at usb?" 55.Cd "uhub* at uhub?" 56.Pp 57.Cd option USBVERBOSE 58.Pp 59.In dev/usb/usb.h 60.In dev/usb/usbhid.h 61.Sh DESCRIPTION 62.Ox 63provides machine-independent bus support and drivers for Universal 64Serial Bus (USB) devices. 65.Pp 66The 67.Ox 68.Nm 69driver has three layers (like 70.Xr scsi 4 71and 72.Xr pcmcia 4 ) : 73the controller, the bus, and the device layer. 74The controller attaches to a physical bus (like 75.Xr pci 4 76or 77.Xr cardbus 4 ) . 78The USB bus attaches to the controller and the root hub attaches 79to the USB bus. 80Devices, which may include further hubs, attach to the root hub. 81The attachment forms the same tree structure as the physical USB 82device tree. 83For each USB device there may be additional drivers attached to it. 84.Pp 85The 86.Cm uhub 87driver controls USB hubs and must always be present since there is 88at least one root hub in any USB system. 89.Pp 90The 91.Cm flags 92are used to specify if the devices on the USB bus should be probed 93early in the boot process. 94If the 95.Cm flags 96are specified with a value of 1, the USB bus will be probed when 97the USB host device is attached instead of waiting until kernel 98processes start running. 99.Pp 100.Ox 101provides support for the following devices. 102Note that not all architectures support all devices. 103.Ss Storage devices 104.Bl -tag -width 12n -offset ind -compact 105.It Xr umass 4 106USB Mass Storage Devices, e.g., external disk drives 107.El 108.Ss Wired network interfaces 109.Bl -tag -width 12n -offset ind -compact 110.It Xr aue 4 111ADMtek AN986/ADM8511 Pegasus family 10/100 USB Ethernet device 112.It Xr axe 4 113ASIX Electronics AX88172/AX88178/AX88772 10/100/Gigabit USB Ethernet device 114.It Xr axen 4 115ASIX Electronics AX88179 10/100/Gigabit USB Ethernet device 116.It Xr cdce 4 117USB Communication Device Class Ethernet device 118.It Xr cue 4 119CATC USB-EL1201A USB Ethernet device 120.It Xr kue 4 121Kawasaki LSI KL5KUSB101B USB Ethernet device 122.It Xr mos 4 123MosChip MCS7730/7830/7832 10/100 USB Ethernet device 124.It Xr mue 4 125Microchip LAN75xx/LAN78xx 10/100/Gigabit USB Ethernet device 126.It Xr smsc 4 127SMSC LAN95xx 10/100 USB Ethernet device 128.It Xr udav 4 129Davicom DM9601 10/100 USB Ethernet device 130.It Xr ure 4 131RealTek RTL8152/RTL8153 10/100/Gigabit USB Ethernet device 132.It Xr url 4 133Realtek RTL8150L 10/100 USB Ethernet device 134.It Xr urndis 4 135USB Remote NDIS Ethernet device 136.El 137.Ss Wireless network interfaces 138.Bl -tag -width 12n -offset ind -compact 139.It Xr athn 4 140Atheros IEEE 802.11a/b/g/n wireless network device 141.It Xr atu 4 142Atmel AT76C50x IEEE 802.11b wireless network device 143.It Xr bwfm 4 144Broadcom and Cypress IEEE 802.11a/ac/b/g/n wireless network device 145.It Xr otus 4 146Atheros USB IEEE 802.11a/b/g/n wireless network device 147.It Xr rsu 4 148Realtek RTL8188SU/RTL8192SU USB IEEE 802.11b/g/n wireless network device 149.It Xr rum 4 150Ralink Technology/MediaTek USB IEEE 802.11a/b/g wireless network device 151.It Xr run 4 152Ralink Technology/MediaTek USB IEEE 802.11a/b/g/n wireless network device 153.It Xr uath 4 154Atheros USB IEEE 802.11a/b/g wireless network device 155.It Xr upgt 4 156Conexant/Intersil PrismGT SoftMAC USB IEEE 802.11b/g wireless network device 157.It Xr ural 4 158Ralink Technology/MediaTek USB IEEE 802.11b/g wireless network device 159.It Xr urtw 4 160Realtek RTL8187L/RTL8187B USB IEEE 802.11b/g wireless network device 161.It Xr urtwn 4 162Realtek RTL8188CU/RTL8188EU/RTL8192CU/RTL8192EU USB IEEE 802.11b/g/n wireless 163network device 164.It Xr wi 4 165Intersil PRISM 2-3 IEEE 802.11b wireless network device 166.It Xr zyd 4 167ZyDAS ZD1211/ZD1211B USB IEEE 802.11b/g wireless network device 168.El 169.Ss Serial and parallel interfaces 170.Bl -tag -width 12n -offset ind -compact 171.It Xr moscom 4 172MosChip Semiconductor MCS7703 based USB serial adapter 173.It Xr uark 4 174Arkmicro Technologies ARK3116 based USB serial adapter 175.It Xr ubsa 4 176Belkin USB serial adapter 177.It Xr uchcom 4 178WinChipHead CH341/340 based USB serial adapter 179.It Xr ucom 4 180USB tty support 181.It Xr ucycom 4 182Cypress microcontroller based USB serial adapter 183.It Xr uftdi 4 184FTDI USB serial adapter 185.It Xr uipaq 4 186iPAQ USB units 187.It Xr ulpt 4 188USB printer support 189.It Xr umcs 4 190MosChip Semiconductor based USB multiport serial adapter 191.It Xr umct 4 192MCT USB-RS232 USB serial adapter 193.It Xr umodem 4 194USB modem support 195.It Xr umsm 4 196Qualcomm MSM modem device 197.It Xr uplcom 4 198Prolific PL-2303 USB serial adapter 199.It Xr uscom 4 200simple USB serial adapters 201.It Xr uslcom 4 202Silicon Laboratories CP210x based USB serial adapter 203.It Xr uslhcom 4 204Silicon Laboratories CP2110 based USB serial adapter 205.It Xr uticom 4 206Texas Instruments TUSB3410 USB serial adapter 207.It Xr uvisor 4 208USB Handspring Visor 209.It Xr uvscom 4 210SUNTAC Slipper U VS-10U USB serial adapter 211.It Xr uxrcom 4 212Exar XR21V1410 USB serial adapter 213.El 214.Ss Audio devices 215.Bl -tag -width 12n -offset ind -compact 216.It Xr uaudio 4 217USB audio devices 218.It Xr umidi 4 219USB MIDI devices 220.El 221.Ss Video devices 222.Bl -tag -width 12n -offset ind -compact 223.It Xr udl 4 224DisplayLink DL-120 / DL-160 USB display devices 225.It Xr utvfu 4 226USB Fushicai USBTV007 audio/video capture device 227.It Xr uvideo 4 228USB video devices 229.El 230.Ss Time receiver devices 231.Bl -tag -width 12n -offset ind -compact 232.It Xr udcf 4 233Gude ADS Expert mouseCLOCK USB timedelta sensor 234.It Xr umbg 4 235Meinberg Funkuhren USB5131 timedelta sensor 236.El 237.Ss Radio receiver devices 238.Bl -tag -width 12n -offset ind -compact 239.It Xr udsbr 4 240D-Link DSB-R100 USB radio device 241.El 242.Ss Human Interface Devices 243.Bl -tag -width 12n -offset ind -compact 244.It Xr ubcmtp 4 245Broadcom trackpad mouse 246.It Xr uhid 4 247Generic driver for Human Interface Devices 248.It Xr uhidev 4 249Base driver for all Human Interface Devices 250.It Xr ukbd 4 251USB keyboards that follow the boot protocol 252.It Xr ums 4 253USB HID mouse, touchscreen and digitiser devices 254.It Xr umt 4 255USB HID multitouch touchpad devices 256.It Xr uoaklux 4 257Toradex OAK USB illuminance sensor 258.It Xr uoakrh 4 259Toradex OAK USB temperature and relative humidity sensor 260.It Xr uoakv 4 261Toradex OAK USB +/-10V 8channel ADC interface 262.It Xr upd 4 263USB Power Devices sensor 264.It Xr uthum 4 265TEMPer HID thermometer and hygrometer 266.It Xr utpms 4 267Apple touchpad mouse 268.It Xr utrh 4 269USBRH temperature and humidity sensor 270.It Xr utwitch 4 271YUREX USB twitch/jiggle of knee sensor 272.It Xr uwacom 4 273Wacom USB tablets 274.El 275.Ss WAN network devices 276.Bl -tag -width 12n -offset ind -compact 277.It Xr umb 4 278USB Mobile Broadband Interface Model (MBIM) 279.El 280.Ss Miscellaneous devices 281.Bl -tag -width 12n -offset ind -compact 282.It Xr uberry 4 283Research In Motion BlackBerry 284.It Xr ugen 4 285USB generic device support 286.It Xr ugl 4 287Genesys Logic based host-to-host adapters 288.It Xr ugold 4 289TEMPer gold HID thermometer and hygrometer 290.It Xr uonerng 4 291Moonbase Otago OneRNG TRNG 292.It Xr uow 4 293Maxim/Dallas DS2490 USB 1-Wire adapter 294.It Xr upl 4 295Prolific based host-to-host adapters 296.It Xr urng 4 297USB Random Number Generator devices 298.It Xr usps 4 299USPS composite AC power and temperature sensor 300.It Xr uts 4 301USB touchscreen support 302.El 303.Sh INTRODUCTION TO USB 304There are different versions of the USB 305which provide different speeds. 306USB 3 can operate up to 5.0Gb/s. 307USB 2 operates at 480Mb/s, while USB versions 1 and 1.1 operate at 30812 Mb/s and 1.5 Mb/s for low speed devices. 309Each USB has a host controller that is the master of the bus; 310all other devices on the bus only speak when spoken to. 311.Pp 312There can be up to 127 devices (apart from the host controller) 313on a bus, each with its own address. 314The addresses are assigned 315dynamically by the host when each device is attached to the bus. 316.Pp 317Within each device there can be up to 16 endpoints. 318Each endpoint 319is individually addressed and the addresses are static. 320Each of these endpoints will communicate in one of four different modes: 321control, isochronous, bulk, or interrupt. 322A device always has at least one endpoint. 323This is a control endpoint at address 0 324and is used to give commands to the device and extract basic data, 325such as descriptors, from the device. 326Each endpoint, except the control endpoint, is unidirectional. 327.Pp 328The endpoints in a device are grouped into interfaces. 329An interface is a logical unit within a device; e.g., 330a compound device with both a keyboard and a trackball would present 331one interface for each. 332An interface can sometimes be set into different modes, 333called alternate settings, which affects how it operates. 334Different alternate settings can have different endpoints 335within it. 336.Pp 337A device may operate in different configurations. 338Depending on the 339configuration the device may present different sets of endpoints 340and interfaces. 341.Pp 342Each device located on a hub has several 343.Xr config 8 344locators: 345.Pp 346.Bl -tag -width configuration -compact 347.It Cd port 348Number of the port on closest upstream hub. 349.It Cd configuration 350Configuration the device must be in for this driver to attach. 351This locator does not set the configuration; it is iterated by the bus 352enumeration. 353.It Cd interface 354Interface number within a device that an interface driver attaches to. 355.It Cd vendor 35616-bit vendor ID of the device. 357.It Cd product 35816-bit product ID of the device. 359.It Cd release 36016-bit release (revision) number of the device. 361.El 362.Pp 363The first locator can be used to pin down a particular device 364according to its physical position in the device tree. 365The last three locators can be used to pin down a particular 366device according to what device it actually is. 367.Pp 368The bus enumeration of the USB bus proceeds in several steps: 369.Bl -enum 370.It 371Any device-specific driver can attach to the device. 372.It 373If none is found, any device class specific driver can attach. 374.It 375If none is found, all configurations are iterated over. 376For each configuration all the interfaces are iterated over and interface 377drivers can attach. 378If any interface driver attached in a certain 379configuration, the iteration over configurations is stopped. 380.It 381If still no drivers have been found, the generic USB driver can attach. 382.El 383.Sh USB CONTROLLER INTERFACE 384Use the following to get access to the USB specific structures 385and defines: 386.Bd -literal -offset indent 387#include <dev/usb/usb.h> 388.Ed 389.Pp 390The 391.Pa /dev/usbN 392device can be opened and a few operations can be performed on it. 393The following 394.Xr ioctl 2 395commands are supported on the controller device: 396.Bl -tag -width xxxxxx 397.It Dv USB_DEVICEINFO Fa "struct usb_device_info" 398This command can be used to retrieve some information about a device 399on the bus. 400The 401.Va udi_addr 402field should be filled before the call and the other fields will 403be filled by information about the device on that address. 404Should no such device exist, an error is reported. 405.Bd -literal 406#define USB_MAX_DEVNAMES 4 407#define USB_MAX_DEVNAMELEN 16 408struct usb_device_info { 409 u_int8_t udi_bus; 410 u_int8_t udi_addr; /* device address */ 411 char udi_product[USB_MAX_STRING_LEN]; 412 char udi_vendor[USB_MAX_STRING_LEN]; 413 char udi_release[8]; 414 u_int16_t udi_productNo; 415 u_int16_t udi_vendorNo; 416 u_int16_t udi_releaseNo; 417 u_int8_t udi_class; 418 u_int8_t udi_subclass; 419 u_int8_t udi_protocol; 420 u_int8_t udi_config; 421 u_int8_t udi_speed; 422#define USB_SPEED_LOW 1 423#define USB_SPEED_FULL 2 424#define USB_SPEED_HIGH 3 425 int udi_power; /* power consumption */ 426 int udi_nports; 427 char udi_devnames[USB_MAX_DEVNAMES] 428 [USB_MAX_DEVNAMELEN]; 429 u_int8_t udi_ports[16]; /* hub only */ 430#define USB_PORT_ENABLED 0xff 431#define USB_PORT_SUSPENDED 0xfe 432#define USB_PORT_POWERED 0xfd 433#define USB_PORT_DISABLED 0xfc 434 char udi_serial[USB_MAX_STRING_LEN]; 435}; 436.Ed 437.Pp 438The 439.Va udi_bus 440field contains the device unit number of the device. 441.Pp 442The 443.Va udi_product , 444.Va udi_vendor , 445and 446.Va udi_release 447fields contain self-explanatory descriptions of the device. 448The 449.Va udi_productNo , 450.Va udi_vendorNo , 451and 452.Va udi_releaseNo 453fields contain numeric identifiers for the device. 454.Pp 455The 456.Va udi_class 457and 458.Va udi_subclass 459fields contain the device class and subclass. 460.Pp 461The 462.Va udi_config 463field shows the current configuration of the device. 464.Pp 465The 466.Va udi_protocol 467field contains the device protocol as given from the device. 468.Pp 469The 470.Va udi_speed 471field 472contains the speed of the device. 473.Pp 474The 475.Va udi_power 476field shows the power consumption in milli-amps drawn at 5 volts 477or is zero if the device is self powered. 478.Pp 479The 480.Va udi_devnames 481field contains the names and instance numbers of the device drivers 482for the devices attached to this device. 483.Pp 484If the device is a hub, the 485.Va udi_nports 486field is non-zero and the 487.Va udi_ports 488field contains the addresses of the connected devices. 489If no device is connected to a port, one of the 490.Dv USB_PORT_* 491values indicates its status. 492.It Dv USB_DEVICESTATS Fa "struct usb_device_stats" 493This command retrieves statistics about the controller. 494.Bd -unfilled 495struct usb_device_stats { 496 u_long uds_requests[4]; 497}; 498.Ed 499.Pp 500The 501.Va uds_requests 502field is indexed by the transfer kind, i.e.\& 503.Dv UE_* , 504and indicates how many transfers of each kind have been completed 505by the controller. 506.It Dv USB_DEVICE_GET_DDESC Fa "struct usb_device_ddesc" 507This command can be used to retrieve the device descriptor 508of a device on the bus. 509The 510.Va udd_addr 511field needs to be filled with the bus device address: 512.Bd -literal 513struct usb_device_ddesc { 514 u_int8_t udd_bus; 515 u_int8_t udd_addr; /* device address */ 516 usb_device_descriptor_t udd_desc; 517}; 518.Ed 519.Pp 520The 521.Va udd_bus 522field contains the device unit number. 523.Pp 524The 525.Va udd_desc 526field contains the device descriptor structure. 527.It Dv USB_DEVICE_GET_CDESC Fa "struct usb_device_cdesc" 528This command can be used to retrieve the configuration descriptor for the 529given configuration of a device on the bus. 530The 531.Va udc_addr 532field needs to be filled with the bus device address. 533The 534.Va udc_config_index 535field needs to be filled with the configuration index for the 536relevant configuration descriptor. 537For convenience the current configuration can be specified by 538.Dv USB_CURRENT_CONFIG_INDEX : 539.Bd -literal 540struct usb_device_cdesc { 541 u_int8_t udc_bus; 542 u_int8_t udc_addr; /* device address */ 543 int udc_config_index; 544 usb_config_descriptor_t udc_desc; 545}; 546.Ed 547.Pp 548The 549.Va udc_bus 550field contains the device unit number. 551.Pp 552The 553.Va udc_desc 554field contains the configuration descriptor structure. 555.It Dv USB_DEVICE_GET_FDESC Fa "struct usb_device_fdesc" 556This command can be used to retrieve all descriptors for the 557given configuration of a device on the bus. 558The 559.Va udf_addr 560field needs to be filled with the bus device address. 561The 562.Va udf_config_index 563field needs to be filled with the configuration index for the 564relevant configuration descriptor. 565For convenience the current configuration can be specified by 566.Dv USB_CURRENT_CONFIG_INDEX . 567The 568.Va udf_data 569field needs to point to a memory area of the size given in the 570.Va udf_size 571field. 572The proper size can be determined by first issuing a 573.Dv USB_DEVICE_GET_CDESC 574command and inspecting the 575.Va wTotalLength 576field: 577.Bd -literal 578struct usb_device_fdesc { 579 u_int8_t udf_bus; 580 u_int8_t udf_addr; /* device address */ 581 int udf_config_index; 582 u_int udf_size; 583 u_char *udf_data; 584}; 585.Ed 586.Pp 587The 588.Va udf_bus 589field contains the device unit number. 590.Pp 591The 592.Va udf_data 593field contains all descriptors. 594.It Dv USB_REQUEST Fa "struct usb_ctl_request" 595This command can be used to execute arbitrary requests on the control pipe. 596This is 597.Em DANGEROUS 598and should be used with great care since it 599can destroy the bus integrity. 600.Pp 601The 602.Vt usb_ctl_request 603structure has the following definition: 604.Bd -literal 605typedef struct { 606 uByte bmRequestType; 607 uByte bRequest; 608 uWord wValue; 609 uWord wIndex; 610 uWord wLength; 611} __packed usb_device_request_t; 612 613struct usb_ctl_request { 614 int ucr_addr; 615 usb_device_request_t ucr_request; 616 void *ucr_data; 617 int ucr_flags; 618#define USBD_SHORT_XFER_OK 0x04 /* allow short reads */ 619 int ucr_actlen; /* actual length transferred */ 620}; 621.Ed 622.Pp 623The 624.Va ucr_addr 625field identifies the device on which to perform the request. 626The 627.Va ucr_request 628field identifies parameters of the request, such as length and type. 629The 630.Va ucr_data 631field contains the location where data will be read from or written to. 632The 633.Va ucr_flags 634field specifies options for the request, and the 635.Va ucr_actlen 636field contains the actual length transferred as the result of the request. 637.El 638.Pp 639The include file 640.In dev/usb/usb.h 641contains definitions for the types used by the various 642.Xr ioctl 2 643calls. 644The naming convention of the fields for the various USB descriptors 645exactly follows the naming in the USB specification. 646Byte sized fields can be accessed directly, but word (16-bit) 647sized fields must be accessed by the 648.Fn UGETW field 649and 650.Fn USETW field value 651macros and double word (32-bit) sized fields must be accessed by the 652.Fn UGETDW field 653and 654.Fn USETDW field value 655macros to handle byte order and alignment properly. 656.Pp 657The include file 658.In dev/usb/usbhid.h 659similarly contains the definitions for 660Human Interface Devices (HID). 661.Sh SEE ALSO 662.Xr usbhidaction 1 , 663.Xr usbhidctl 1 , 664.Xr ioctl 2 , 665.Xr dwctwo 4 , 666.Xr ehci 4 , 667.Xr ohci 4 , 668.Xr uhci 4 , 669.Xr xhci 4 , 670.Xr config 8 , 671.Xr usbdevs 8 672.Pp 673The USB specifications can be found at 674.Lk http://www.usb.org/developers/docs/ 675.Sh HISTORY 676The 677.Nm 678driver 679appeared in 680.Ox 2.6 . 681