1.\" Copyright (c) 2004 Daniel Hartmeier 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 8.\" - Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" - Redistributions in binary form must reproduce the above 11.\" copyright notice, this list of conditions and the following 12.\" disclaimer in the documentation and/or other materials provided 13.\" with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16.\" "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17.\" LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18.\" FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19.\" COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 23.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 25.\" ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26.\" POSSIBILITY OF SUCH DAMAGE. 27.\" 28.\" $OpenBSD: cdce.4,v 1.22 2016/09/03 14:54:24 guenther Exp $ 29.\" 30.Dd $Mdocdate: September 3 2016 $ 31.Dt CDCE 4 32.Os 33.Sh NAME 34.Nm cdce 35.Nd USB Communication Device Class Ethernet device 36.Sh SYNOPSIS 37.Cd "cdce* at uhub?" 38.Sh DESCRIPTION 39The 40.Nm 41driver provides support for USB Host-to-Host (aka USB-to-USB) bridges 42based on the USB Communication Device Class (CDC) and Ethernet subclass, 43including the following: 44.Pp 45.Bl -bullet -compact -offset indent 46.It 47Acer Labs USB 2.0 Data Link 48.It 49Dell Wireless 5530 50.It 51Dell Wireless 5540 52.It 53FRITZ!Box Fon ata 1020 54.It 55G.Mate YP3X00 56.It 57Lenovo Thinkpad USB 3.0 Ethernet Adapter (FRU 03X6903) 58.It 59Motorola USBNET 60.It 61NetChip EthernetGadget 62.It 63Prolific PL-2501 64.It 65Sony Ericsson K610i 66.It 67Sony Ericsson F3705g 68.It 69Yota LU156 70.It 71Zyxel P-971M 72.El 73.Pp 74The USB bridge appears as a regular network interface on both sides, 75transporting Ethernet frames. 76USB 1.x bridges support speeds of up to 12Mbps, and USB 2.0 speeds of 77up to 480Mbps. 78Packets are 79received and transmitted over separate USB bulk transfer endpoints. 80.Pp 81The 82.Nm 83driver does not support different media types or options. 84For more information on configuring this device, see 85.Xr ifconfig 8 . 86.Sh DIAGNOSTICS 87.Bl -diag 88.It "cdce0: extra ethernet descriptor" 89There is more than one Ethernet descriptor. 90.It "cdce0: no data interface" 91The data interface announced by the union descriptor cannot be found. 92.It "cdce0: no descriptor for interrupt endpoint N" 93.It "cdce0: interface alternate setting N failed" 94.It "cdce0: no descriptor for bulk endpoint N" 95.It "cdce0: could not find data bulk in/out" 96For a manually added USB vendor/product, these errors indicate 97that the bridge is not compatible with the driver. 98.It "cdce0: watchdog timeout" 99A packet was queued for transmission and a transmit command was 100issued, however the device failed to acknowledge the transmission 101before a timeout expired. 102.It "cdce0: no memory for rx list -- packet dropped!" 103Memory allocation through MGETHDR or MCLGET failed, the system 104is running low on mbufs. 105.It "cdce0: abort/close rx/tx/interrupt pipe failed" 106.It "cdce0: rx/tx list init failed" 107.It "cdce0: open rx/tx/interrupt pipe failed" 108.It "cdce0: usb error on rx/tx" 109.El 110.Sh SEE ALSO 111.Xr arp 4 , 112.Xr intro 4 , 113.Xr netintro 4 , 114.Xr usb 4 , 115.Xr hostname.if 5 , 116.Xr ifconfig 8 117.Rs 118.%T "Universal Serial Bus Class Definitions for Communication Devices" 119.%U http://www.usb.org/developers/devclass_docs/usbcdc11.pdf 120.Re 121.Rs 122.%T "Data sheet Prolific PL-2501 Host-to-Host Bridge/Network Controller" 123.Re 124.Sh HISTORY 125The 126.Nm 127device driver first appeared in 128.Ox 3.6 . 129.Sh AUTHORS 130.An -nosplit 131The 132.Nm 133driver was written by 134.An Craig Boston Aq Mt craig@tobuj.gank.org 135based on the 136.Xr aue 4 137driver written by 138.An Bill Paul Aq Mt wpaul@windriver.com 139and ported to 140.Ox 141by 142.An Daniel Hartmeier Aq Mt dhartmei@openbsd.org . 143.Sh CAVEATS 144Many USB devices notoriously fail to report their class and interfaces 145correctly. 146Undetected products might work flawlessly when their vendor and product IDs 147are added to the driver manually. 148