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 1.4 2004/12/08 18:35:56 peter Exp $ 29.\" $FreeBSD$ 30.\" 31.Dd April 26, 2018 32.Dt CDCE 4 33.Os 34.Sh NAME 35.Nm cdce 36.Nd "USB Communication Device Class Ethernet (CDC ECM/NCM) driver" 37.Sh SYNOPSIS 38To compile this driver into the kernel, 39place the following lines in your 40kernel configuration file: 41.Bd -ragged -offset indent 42.Cd "device uhci" 43.Cd "device ohci" 44.Cd "device usb" 45.Cd "device miibus" 46.Cd "device uether" 47.Cd "device cdce" 48.Ed 49.Pp 50Alternatively, to load the driver as a 51module at boot time, place the following line in 52.Xr loader.conf 5 : 53.Bd -literal -offset indent 54if_cdce_load="YES" 55.Ed 56.Sh DESCRIPTION 57The 58.Nm 59driver provides support for USB Host-to-Host (aka USB-to-USB) and 60USB-to-Ethernet bridges based on the USB Communication Device Class 61Ethernet Control Model (CDC ECM) and Network Control Model (CDC NCM) 62specifications. 63It also provides device-level CDC ECM support. 64.Pp 65The USB bridge appears as a regular network interface on both sides, 66transporting Ethernet frames. 67.Pp 68For more information on configuring this device, see 69.Xr ifconfig 8 . 70.Pp 71USB 1.x bridges support speeds of up to 12Mbps, and USB 2.0 speeds of 72up to 480Mbps. 73.Pp 74Packets are 75received and transmitted over separate USB bulk transfer endpoints. 76.Pp 77The 78.Nm 79driver does not support different media types or options. 80.Sh HARDWARE 81The following devices are supported by the 82.Nm 83driver: 84.Pp 85.Bl -bullet -compact 86.It 87Prolific PL-2501 Host-to-Host Bridge Controller 88.It 89Sharp Zaurus PDA 90.It 91Terayon TJ-715 DOCSIS Cable Modem 92.El 93.Sh DIAGNOSTICS 94.Bl -diag 95.It "cdce%d: no union descriptor" 96The driver could not fetch an interface descriptor from the USB 97device. 98For a manually added USB vendor/product, the CDCE_NO_UNION flag 99can be tried to work around the missing descriptor. 100.It "cdce%d: no data interface" 101.It "cdce%d: could not read endpoint descriptor" 102.It "cdce%d: unexpected endpoint" 103.It "cdce%d: could not find data bulk in/out" 104For a manually added USB vendor/product, these errors indicate 105that the bridge is not compatible with the driver. 106.It "cdce%d: watchdog timeout" 107A packet was queued for transmission and a transmit command was 108issued, however the device failed to acknowledge the transmission 109before a timeout expired. 110.It "cdce%d: no memory for rx list -- packet dropped!" 111Memory allocation through MGETHDR or MCLGET failed, the system 112is running low on mbufs. 113.It "cdce%d: abort/close rx/tx pipe failed" 114.It "cdce%d: rx/tx list init failed" 115.It "cdce%d: open rx/tx pipe failed" 116.It "cdce%d: usb error on rx/tx" 117.El 118.Sh SEE ALSO 119.Xr arp 4 , 120.Xr intro 4 , 121.Xr ipheth 4 , 122.Xr netintro 4 , 123.Xr urndis 4 , 124.Xr usb 4 , 125.Xr ifconfig 8 126.Rs 127.%T "Universal Serial Bus Class Definitions for Communication Devices" 128.%U http://www.usb.org/developers/devclass_docs/usbcdc11.pdf 129.Re 130.Rs 131.%T "Data sheet Prolific PL-2501 Host-to-Host Bridge/Network Controller" 132.%U http://tech.prolific.com.tw/visitor/fcabdl.asp?fid=20679530 133.Re 134.Sh HISTORY 135The 136.Nm 137device driver first appeared in 138.Ox 3.6 , 139.Nx 3.0 140and 141.Fx 6.0 . 142.Sh AUTHORS 143.An -nosplit 144The 145.Nm 146driver was written by 147.An Craig Boston Aq Mt craig@tobuj.gank.org 148based on the 149.Xr aue 4 150driver written by 151.An Bill Paul Aq Mt wpaul@windriver.com 152and ported to 153.Ox 154by 155.An Daniel Hartmeier Aq Mt dhartmei@openbsd.org . 156.Sh CAVEATS 157Many USB devices notoriously fail to report their class and interfaces 158correctly. 159Undetected products might work flawlessly when their vendor and product IDs 160are added to the driver manually. 161