xref: /freebsd/share/man/man4/cdceem.4 (revision 2008043f386721d58158e37e0d7e50df8095942d)
1.\" Copyright (c) 2019 Edward Tomasz Napierala <trasz@FreeBSD.org>
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23.Dd November 7, 2019
24.Dt CDCEEM 4
25.Os
26.Sh NAME
27.Nm cdceem
28.Nd "USB Communication Device Class Ethernet Emulation Model (CDC EEM) driver"
29.Sh SYNOPSIS
30To compile this driver into the kernel,
31place the following lines in your
32kernel configuration file:
33.Bd -ragged -offset indent
34.Cd "device uhci"
35.Cd "device ohci"
36.Cd "device usb"
37.Cd "device miibus"
38.Cd "device uether"
39.Cd "device cdceem"
40.Ed
41.Pp
42Alternatively, to load the driver as a
43module at boot time, place the following line in
44.Xr loader.conf 5 :
45.Bd -literal -offset indent
46if_cdceem_load="YES"
47.Ed
48.Sh DESCRIPTION
49The
50.Nm
51driver provides support for USB devices based on the USB Communication
52Device Class Ethernet Emulation Model (CDC EEM) specification.
53.Pp
54The driver works on both host, and device-side; see
55.Xr usb_template 4
56for details.
57.Pp
58The USB device appears as a regular network interface on both sides,
59transporting Ethernet frames.
60.Pp
61For more information on configuring this device, see
62.Xr ifconfig 8 .
63.Pp
64The
65.Nm
66driver does not support different media types or options.
67.Sh SYSCTL VARIABLES
68The following variables are available as both
69.Xr sysctl 8
70variables and
71.Xr loader 8
72tunables:
73.Bl -tag -width indent
74.It Va hw.usb.cdceem.debug
75Verbosity level for log messages from the
76.Nm
77driver.
78Set to 0 to disable logging or 1 to warn about potential problems.
79Larger values enable debugging output.
80Defaults to 1.
81.It Va hw.usb.cdceem.send_echoes
82If set to 1, the driver will send an Echo EEM packet when the
83interface is brought up.
84While responding to Echo is mandatory, some devices cannot handle it.
85Only use for debugging.
86Defaults to 0.
87.It Va hw.usb.cdceem.send_fake_crc
88If set to 1, the driver will use 0xdeadbeef as the CRC value
89for outgoing Data EEM packets.
90Only use for debugging.
91Defaults to 0.
92.El
93.Sh SEE ALSO
94.Xr arp 4 ,
95.Xr cdce 4 ,
96.Xr intro 4 ,
97.Xr ipheth 4 ,
98.Xr netintro 4 ,
99.Xr urndis 4 ,
100.Xr usb 4 ,
101.Xr usb_template 4 ,
102.Xr ifconfig 8
103.Rs
104.%T "Universal Serial Bus Communications Class Subclass Specification for Ethernet Emulation Model Devices"
105.%U https://usb.org/sites/default/files/CDC_EEM10.pdf
106.Re
107.Sh HISTORY
108The
109.Nm
110device driver first appeared in
111.Fx 12.1 .
112.Sh AUTHORS
113The
114.Nm
115driver was written by
116.An Edward Tomasz Napierala Aq Mt trasz@FreeBSD.org
117under sponsorship from Hewlett Packard Enterprise.
118