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.\" $NetBSD: cdce.4,v 1.10 2014/03/18 18:20:39 riastradh Exp $ 29.\" 30.Dd June 7, 2011 31.Dt CDCE 4 32.Os 33.Sh NAME 34.Nm cdce 35.Nd USB Communication Device Class Ethernet driver 36.Sh SYNOPSIS 37.Cd "cdce* at uhub? port ?" 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 46.It 47Acer Labs USB 2.0 Data Link 48.It 49G.Mate YP3X00 50.It 51Motorola USBNET 52.It 53NetChip EthernetGadget 54.It 55Prolific PL-2501 56.It 57Sharp Zaurus 58.El 59.Pp 60The USB bridge appears as a regular network interface on both sides, 61transporting Ethernet frames. 62.Pp 63For more information on configuring this device, see 64.Xr ifconfig 8 . 65.Pp 66USB 1.x bridges support speeds of up to 12Mbps, and USB 2.0 speeds of 67up to 480Mbps. 68.Pp 69Packets are 70received and transmitted over separate USB bulk transfer endpoints. 71.Pp 72The 73.Nm 74driver does not support different media types or options. 75.Sh DIAGNOSTICS 76.Bl -diag 77.It "cdce%d: no union descriptor" 78The driver couldn't fetch an interface descriptor from the USB 79device. 80For a manually added USB vendor/product, the CDCE_NO_UNION flag 81can be tried to work around the missing descriptor. 82.It "cdce%d: no data interface" 83.It "cdce%d: could not read endpoint descriptor" 84.It "cdce%d: unexpected endpoint" 85.It "cdce%d: could not find data bulk in/out" 86For a manually added USB vendor/product, these errors indicate 87that the bridge is not compatible with the driver. 88.It "cdce%d: watchdog timeout" 89A packet was queued for transmission and a transmit command was 90issued, however the device failed to acknowledge the transmission 91before a timeout expired. 92.It "cdce%d: no memory for rx list -- packet dropped!" 93Memory allocation through MGETHDR or MCLGET failed, the system 94is running low on mbufs. 95.It "cdce%d: abort/close rx/tx pipe failed" 96.It "cdce%d: rx/tx list init failed" 97.It "cdce%d: open rx/tx pipe failed" 98.It "cdce%d: usb error on rx/tx" 99.El 100.Sh SEE ALSO 101.Xr arp 4 , 102.Xr intro 4 , 103.Xr netintro 4 , 104.Xr usb 4 , 105.\" .Xr hostname.if 5 , 106.Xr ifconfig 8 107.Rs 108.%T "Universal Serial Bus Class Definitions for Communication Devices" 109.%U http://www.usb.org/developers/devclass_docs/usbcdc11.pdf 110.Re 111.Rs 112.%T "Data sheet Prolific PL-2501 Host-to-Host Bridge/Network Controller" 113.%U http://tech.prolific.com.tw/visitor/fcabdl.asp?fid=20679530 114.Re 115.Sh HISTORY 116The 117.Nm 118device driver first appeared in 119.Ox 3.6 120and 121.Nx 3.0 . 122.Sh AUTHORS 123.An -nosplit 124The 125.Nm 126driver was written by 127.An Craig Boston Aq Mt craig@tobuj.gank.org 128based on the 129.Xr aue 4 130driver written by 131.An Bill Paul Aq Mt wpaul@windriver.com 132and ported to 133.Ox 134by 135.An Daniel Hartmeier Aq Mt dhartmei@openbsd.org . 136.Sh CAVEATS 137Many USB devices notoriously fail to report their class and interfaces 138correctly. 139Undetected products might work flawlessly when their vendor and product IDs 140are added to the driver manually. 141