NAME

     cdceem — USB Communication Device Class Ethernet Emulation Model (CDC EEM) driver

SYNOPSIS

     To compile this driver into the kernel, place the following lines in your kernel
     configuration file:

           device uhci
           device ohci
           device usb
           device miibus
           device uether
           device cdceem

     Alternatively, to load the driver as a module at boot time, place the following line in
     loader.conf(5):

           if_cdceem_load="YES"

DESCRIPTION

     The cdceem driver provides support for USB devices based on the USB Communication Device
     Class Ethernet Emulation Model (CDC EEM) specification.

     The driver works on both host, and device-side; see usb_template(4) for details.

     The USB device appears as a regular network interface on both sides, transporting Ethernet
     frames.

     For more information on configuring this device, see ifconfig(8).

     The cdceem driver does not support different media types or options.

SYSCTL VARIABLES

     The following variables are available as both sysctl(8) variables and loader(8) tunables:

     hw.usb.cdceem.debug
             Verbosity level for log messages from the cdceem driver.  Set to 0 to disable
             logging or 1 to warn about potential problems.  Larger values enable debugging
             output.  Defaults to 1.

     hw.usb.cdceem.send_echoes
             If set to 1, the driver will send an Echo EEM packet when the interface is brought
             up.  While responding to Echo is mandatory, some devices cannot handle it.  Only use
             for debugging.  Defaults to 0.

     hw.usb.cdceem.send_fake_crc
             If set to 1, the driver will use 0xdeadbeef as the CRC value for outgoing Data EEM
             packets.  Only use for debugging.  Defaults to 0.

SEE ALSO

     arp(4), cdce(4), intro(4), ipheth(4), netintro(4), urndis(4), usb(4), usb_template(4),
     ifconfig(8)

     Universal Serial Bus Communications Class Subclass Specification for Ethernet Emulation
     Model Devices, https://usb.org/sites/default/files/CDC_EEM10.pdf.

HISTORY

     The cdceem device driver first appeared in FreeBSD 13.0.

AUTHORS

     The cdceem driver was written by Edward Tomasz Napierala <trasz@FreeBSD.org> under
     sponsorship from Hewlett Packard Enterprise.