1.\" $OpenBSD: usb.4,v 1.196 2019/06/07 20:52:13 jmc 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: June 7 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 ucrcom 4 182Chromebook USB serial console 183.It Xr ucycom 4 184Cypress microcontroller based USB serial adapter 185.It Xr uftdi 4 186FTDI USB serial adapter 187.It Xr uipaq 4 188iPAQ USB units 189.It Xr ukspan 4 190Keyspan USB serial adapter 191.It Xr ulpt 4 192USB printer support 193.It Xr umcs 4 194MosChip Semiconductor based USB multiport serial adapter 195.It Xr umct 4 196MCT USB-RS232 USB serial adapter 197.It Xr umodem 4 198USB modem support 199.It Xr umsm 4 200Qualcomm MSM modem device 201.It Xr uplcom 4 202Prolific PL-2303 USB serial adapter 203.It Xr uscom 4 204simple USB serial adapters 205.It Xr uslcom 4 206Silicon Laboratories CP210x based USB serial adapter 207.It Xr uslhcom 4 208Silicon Laboratories CP2110 based USB serial adapter 209.It Xr uticom 4 210Texas Instruments TUSB3410 USB serial adapter 211.It Xr uvisor 4 212USB Handspring Visor 213.It Xr uvscom 4 214SUNTAC Slipper U VS-10U USB serial adapter 215.It Xr uxrcom 4 216Exar XR21V1410 USB serial adapter 217.El 218.Ss Audio devices 219.Bl -tag -width 12n -offset ind -compact 220.It Xr uaudio 4 221USB audio devices 222.It Xr umidi 4 223USB MIDI devices 224.El 225.Ss Video devices 226.Bl -tag -width 12n -offset ind -compact 227.It Xr udl 4 228DisplayLink DL-120 / DL-160 USB display devices 229.It Xr utvfu 4 230USB Fushicai USBTV007 audio/video capture device 231.It Xr uvideo 4 232USB video devices 233.El 234.Ss Time receiver devices 235.Bl -tag -width 12n -offset ind -compact 236.It Xr udcf 4 237Gude ADS Expert mouseCLOCK USB timedelta sensor 238.It Xr umbg 4 239Meinberg Funkuhren USB5131 timedelta sensor 240.El 241.Ss Radio receiver devices 242.Bl -tag -width 12n -offset ind -compact 243.It Xr udsbr 4 244D-Link DSB-R100 USB radio device 245.El 246.Ss Human Interface Devices 247.Bl -tag -width 12n -offset ind -compact 248.It Xr ubcmtp 4 249Broadcom trackpad mouse 250.It Xr uhid 4 251Generic driver for Human Interface Devices 252.It Xr uhidev 4 253Base driver for all Human Interface Devices 254.It Xr ukbd 4 255USB keyboards that follow the boot protocol 256.It Xr ums 4 257USB HID mouse, touchscreen and digitiser devices 258.It Xr umt 4 259USB HID multitouch touchpad devices 260.It Xr uoaklux 4 261Toradex OAK USB illuminance sensor 262.It Xr uoakrh 4 263Toradex OAK USB temperature and relative humidity sensor 264.It Xr uoakv 4 265Toradex OAK USB +/-10V 8channel ADC interface 266.It Xr upd 4 267USB Power Devices sensor 268.It Xr uthum 4 269TEMPer HID thermometer and hygrometer 270.It Xr utpms 4 271Apple touchpad mouse 272.It Xr utrh 4 273USBRH temperature and humidity sensor 274.It Xr utwitch 4 275YUREX USB twitch/jiggle of knee sensor 276.It Xr uwacom 4 277Wacom USB tablets 278.El 279.Ss WAN network devices 280.Bl -tag -width 12n -offset ind -compact 281.It Xr umb 4 282USB Mobile Broadband Interface Model (MBIM) 283.El 284.Ss Miscellaneous devices 285.Bl -tag -width 12n -offset ind -compact 286.It Xr uberry 4 287Research In Motion BlackBerry 288.It Xr ugen 4 289USB generic device support 290.It Xr ugl 4 291Genesys Logic based host-to-host adapters 292.It Xr ugold 4 293TEMPer gold HID thermometer and hygrometer 294.It Xr uonerng 4 295Moonbase Otago OneRNG TRNG 296.It Xr uow 4 297Maxim/Dallas DS2490 USB 1-Wire adapter 298.It Xr upl 4 299Prolific based host-to-host adapters 300.It Xr urng 4 301USB Random Number Generator devices 302.It Xr usps 4 303USPS composite AC power and temperature sensor 304.It Xr uts 4 305USB touchscreen support 306.El 307.Sh INTRODUCTION TO USB 308There are different versions of the USB 309which provide different speeds. 310USB 3 can operate up to 5.0Gb/s. 311USB 2 operates at 480Mb/s, while USB versions 1 and 1.1 operate at 31212 Mb/s and 1.5 Mb/s for low speed devices. 313Each USB has a host controller that is the master of the bus; 314all other devices on the bus only speak when spoken to. 315.Pp 316There can be up to 127 devices (apart from the host controller) 317on a bus, each with its own address. 318The addresses are assigned 319dynamically by the host when each device is attached to the bus. 320.Pp 321Within each device there can be up to 16 endpoints. 322Each endpoint 323is individually addressed and the addresses are static. 324Each of these endpoints will communicate in one of four different modes: 325control, isochronous, bulk, or interrupt. 326A device always has at least one endpoint. 327This is a control endpoint at address 0 328and is used to give commands to the device and extract basic data, 329such as descriptors, from the device. 330Each endpoint, except the control endpoint, is unidirectional. 331.Pp 332The endpoints in a device are grouped into interfaces. 333An interface is a logical unit within a device; e.g., 334a compound device with both a keyboard and a trackball would present 335one interface for each. 336An interface can sometimes be set into different modes, 337called alternate settings, which affects how it operates. 338Different alternate settings can have different endpoints 339within it. 340.Pp 341A device may operate in different configurations. 342Depending on the 343configuration the device may present different sets of endpoints 344and interfaces. 345.Pp 346Each device located on a hub has several 347.Xr config 8 348locators: 349.Pp 350.Bl -tag -width configuration -compact 351.It Cd port 352Number of the port on closest upstream hub. 353.It Cd configuration 354Configuration the device must be in for this driver to attach. 355This locator does not set the configuration; it is iterated by the bus 356enumeration. 357.It Cd interface 358Interface number within a device that an interface driver attaches to. 359.It Cd vendor 36016-bit vendor ID of the device. 361.It Cd product 36216-bit product ID of the device. 363.It Cd release 36416-bit release (revision) number of the device. 365.El 366.Pp 367The first locator can be used to pin down a particular device 368according to its physical position in the device tree. 369The last three locators can be used to pin down a particular 370device according to what device it actually is. 371.Pp 372The bus enumeration of the USB bus proceeds in several steps: 373.Bl -enum 374.It 375Any device-specific driver can attach to the device. 376.It 377If none is found, any device class specific driver can attach. 378.It 379If none is found, all configurations are iterated over. 380For each configuration all the interfaces are iterated over and interface 381drivers can attach. 382If any interface driver attached in a certain 383configuration, the iteration over configurations is stopped. 384.It 385If still no drivers have been found, the generic USB driver can attach. 386.El 387.Sh USB CONTROLLER INTERFACE 388Use the following to get access to the USB specific structures 389and defines: 390.Bd -literal -offset indent 391#include <dev/usb/usb.h> 392.Ed 393.Pp 394The 395.Pa /dev/usbN 396device can be opened and a few operations can be performed on it. 397The following 398.Xr ioctl 2 399commands are supported on the controller device: 400.Bl -tag -width xxxxxx 401.It Dv USB_DEVICEINFO Fa "struct usb_device_info" 402This command can be used to retrieve some information about a device 403on the bus. 404The 405.Va udi_addr 406field should be filled before the call and the other fields will 407be filled by information about the device on that address. 408Should no such device exist, an error is reported. 409.Bd -literal 410#define USB_MAX_DEVNAMES 4 411#define USB_MAX_DEVNAMELEN 16 412struct usb_device_info { 413 u_int8_t udi_bus; 414 u_int8_t udi_addr; /* device address */ 415 char udi_product[USB_MAX_STRING_LEN]; 416 char udi_vendor[USB_MAX_STRING_LEN]; 417 char udi_release[8]; 418 u_int16_t udi_productNo; 419 u_int16_t udi_vendorNo; 420 u_int16_t udi_releaseNo; 421 u_int8_t udi_class; 422 u_int8_t udi_subclass; 423 u_int8_t udi_protocol; 424 u_int8_t udi_config; 425 u_int8_t udi_speed; 426#define USB_SPEED_LOW 1 427#define USB_SPEED_FULL 2 428#define USB_SPEED_HIGH 3 429 int udi_power; /* power consumption */ 430 int udi_nports; 431 char udi_devnames[USB_MAX_DEVNAMES] 432 [USB_MAX_DEVNAMELEN]; 433 u_int8_t udi_ports[16]; /* hub only */ 434#define USB_PORT_ENABLED 0xff 435#define USB_PORT_SUSPENDED 0xfe 436#define USB_PORT_POWERED 0xfd 437#define USB_PORT_DISABLED 0xfc 438 char udi_serial[USB_MAX_STRING_LEN]; 439}; 440.Ed 441.Pp 442The 443.Va udi_bus 444field contains the device unit number of the device. 445.Pp 446The 447.Va udi_product , 448.Va udi_vendor , 449and 450.Va udi_release 451fields contain self-explanatory descriptions of the device. 452The 453.Va udi_productNo , 454.Va udi_vendorNo , 455and 456.Va udi_releaseNo 457fields contain numeric identifiers for the device. 458.Pp 459The 460.Va udi_class 461and 462.Va udi_subclass 463fields contain the device class and subclass. 464.Pp 465The 466.Va udi_config 467field shows the current configuration of the device. 468.Pp 469The 470.Va udi_protocol 471field contains the device protocol as given from the device. 472.Pp 473The 474.Va udi_speed 475field 476contains the speed of the device. 477.Pp 478The 479.Va udi_power 480field shows the power consumption in milli-amps drawn at 5 volts 481or is zero if the device is self powered. 482.Pp 483The 484.Va udi_devnames 485field contains the names and instance numbers of the device drivers 486for the devices attached to this device. 487.Pp 488If the device is a hub, the 489.Va udi_nports 490field is non-zero and the 491.Va udi_ports 492field contains the addresses of the connected devices. 493If no device is connected to a port, one of the 494.Dv USB_PORT_* 495values indicates its status. 496.It Dv USB_DEVICESTATS Fa "struct usb_device_stats" 497This command retrieves statistics about the controller. 498.Bd -unfilled 499struct usb_device_stats { 500 u_long uds_requests[4]; 501}; 502.Ed 503.Pp 504The 505.Va uds_requests 506field is indexed by the transfer kind, i.e.\& 507.Dv UE_* , 508and indicates how many transfers of each kind have been completed 509by the controller. 510.It Dv USB_DEVICE_GET_DDESC Fa "struct usb_device_ddesc" 511This command can be used to retrieve the device descriptor 512of a device on the bus. 513The 514.Va udd_addr 515field needs to be filled with the bus device address: 516.Bd -literal 517struct usb_device_ddesc { 518 u_int8_t udd_bus; 519 u_int8_t udd_addr; /* device address */ 520 usb_device_descriptor_t udd_desc; 521}; 522.Ed 523.Pp 524The 525.Va udd_bus 526field contains the device unit number. 527.Pp 528The 529.Va udd_desc 530field contains the device descriptor structure. 531.It Dv USB_DEVICE_GET_CDESC Fa "struct usb_device_cdesc" 532This command can be used to retrieve the configuration descriptor for the 533given configuration of a device on the bus. 534The 535.Va udc_addr 536field needs to be filled with the bus device address. 537The 538.Va udc_config_index 539field needs to be filled with the configuration index for the 540relevant configuration descriptor. 541For convenience the current configuration can be specified by 542.Dv USB_CURRENT_CONFIG_INDEX : 543.Bd -literal 544struct usb_device_cdesc { 545 u_int8_t udc_bus; 546 u_int8_t udc_addr; /* device address */ 547 int udc_config_index; 548 usb_config_descriptor_t udc_desc; 549}; 550.Ed 551.Pp 552The 553.Va udc_bus 554field contains the device unit number. 555.Pp 556The 557.Va udc_desc 558field contains the configuration descriptor structure. 559.It Dv USB_DEVICE_GET_FDESC Fa "struct usb_device_fdesc" 560This command can be used to retrieve all descriptors for the 561given configuration of a device on the bus. 562The 563.Va udf_addr 564field needs to be filled with the bus device address. 565The 566.Va udf_config_index 567field needs to be filled with the configuration index for the 568relevant configuration descriptor. 569For convenience the current configuration can be specified by 570.Dv USB_CURRENT_CONFIG_INDEX . 571The 572.Va udf_data 573field needs to point to a memory area of the size given in the 574.Va udf_size 575field. 576The proper size can be determined by first issuing a 577.Dv USB_DEVICE_GET_CDESC 578command and inspecting the 579.Va wTotalLength 580field: 581.Bd -literal 582struct usb_device_fdesc { 583 u_int8_t udf_bus; 584 u_int8_t udf_addr; /* device address */ 585 int udf_config_index; 586 u_int udf_size; 587 u_char *udf_data; 588}; 589.Ed 590.Pp 591The 592.Va udf_bus 593field contains the device unit number. 594.Pp 595The 596.Va udf_data 597field contains all descriptors. 598.It Dv USB_REQUEST Fa "struct usb_ctl_request" 599This command can be used to execute arbitrary requests on the control pipe. 600This is 601.Em DANGEROUS 602and should be used with great care since it 603can destroy the bus integrity. 604.Pp 605The 606.Vt usb_ctl_request 607structure has the following definition: 608.Bd -literal 609typedef struct { 610 uByte bmRequestType; 611 uByte bRequest; 612 uWord wValue; 613 uWord wIndex; 614 uWord wLength; 615} __packed usb_device_request_t; 616 617struct usb_ctl_request { 618 int ucr_addr; 619 usb_device_request_t ucr_request; 620 void *ucr_data; 621 int ucr_flags; 622#define USBD_SHORT_XFER_OK 0x04 /* allow short reads */ 623 int ucr_actlen; /* actual length transferred */ 624}; 625.Ed 626.Pp 627The 628.Va ucr_addr 629field identifies the device on which to perform the request. 630The 631.Va ucr_request 632field identifies parameters of the request, such as length and type. 633The 634.Va ucr_data 635field contains the location where data will be read from or written to. 636The 637.Va ucr_flags 638field specifies options for the request, and the 639.Va ucr_actlen 640field contains the actual length transferred as the result of the request. 641.El 642.Pp 643The include file 644.In dev/usb/usb.h 645contains definitions for the types used by the various 646.Xr ioctl 2 647calls. 648The naming convention of the fields for the various USB descriptors 649exactly follows the naming in the USB specification. 650Byte sized fields can be accessed directly, but word (16-bit) 651sized fields must be accessed by the 652.Fn UGETW field 653and 654.Fn USETW field value 655macros and double word (32-bit) sized fields must be accessed by the 656.Fn UGETDW field 657and 658.Fn USETDW field value 659macros to handle byte order and alignment properly. 660.Pp 661The include file 662.In dev/usb/usbhid.h 663similarly contains the definitions for 664Human Interface Devices (HID). 665.Sh SEE ALSO 666.Xr usbhidaction 1 , 667.Xr usbhidctl 1 , 668.Xr ioctl 2 , 669.Xr dwctwo 4 , 670.Xr ehci 4 , 671.Xr ohci 4 , 672.Xr uhci 4 , 673.Xr xhci 4 , 674.Xr config 8 , 675.Xr usbdevs 8 676.Pp 677The USB specifications can be found at 678.Lk http://www.usb.org/developers/docs/ 679.Sh HISTORY 680The 681.Nm 682driver 683appeared in 684.Ox 2.6 . 685