.\" $OpenBSD: athn.4,v 1.18 2011/09/03 22:59:08 jmc Exp $
.\"
.\" Copyright (c) 2009 Damien Bergamini <damien.bergamini@free.fr>.
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: September 3 2011 $
.Dt ATHN 4
.Os
.Sh NAME
.Nm athn
.Nd Atheros IEEE 802.11a/g/n wireless network device
.Sh SYNOPSIS
.Cd "athn* at cardbus?"
.Cd "athn* at pci?"
.Cd "athn* at uhub? port ?"
.Sh DESCRIPTION
The
.Nm
driver provides support for a wide variety of
Atheros 802.11n devices, ranging from the AR5008 up to the AR9287.
.Pp
The AR5008 (codenamed Owl) is the first generation of
Atheros 802.11n solutions.
It consists of two chips, a MAC/Baseband Processor and a Radio-on-a-Chip.
The MAC/Baseband Processor can be an AR5416 (PCI and CardBus form factors)
or an AR5418 (PCIe Mini Card form factor).
The radio can be an AR2122, AR2133, AR5122 or an AR5133 chip.
The AR2122 chip operates in the 2GHz spectrum and supports up to 2
transmit paths and 2 receiver paths (2T2R).
The AR2133 chip operates in the 2GHz spectrum and supports up to 3
transmit paths and 3 receiver paths (3T3R).
The AR5122 chip operates in the 2GHz and 5GHz spectra and supports
up to 2 transmit paths and 2 receiver paths (2T2R).
The AR5133 chip operates in the 2GHz and 5GHz spectra and supports
up to 3 transmit paths and 3 receiver paths (3T3R).
.Pp
The AR9001 (codenamed Sowl) is a Mini-PCI 802.11n solution.
It consists of two chips, an AR9160 MAC/Baseband Processor and an
AR9103 or AR9106 Radio-on-a-Chip.
The AR9103 chip operates in the 2GHz spectrum and supports up to 3
transmit paths and 3 receiver paths (3T3R).
The AR9106 chip operates in the 2GHz and 5GHz spectra and supports
up to 3 transmit paths and 3 receiver paths (3T3R).
.Pp
The AR9220, AR9223 and AR9280 (codenamed Merlin) are the
first generation of
Atheros single-chip 802.11n solutions.
The AR9220 and AR9223 exist in PCI and Mini-PCI form factors.
The AR9280 exists in PCIe Mini Card (XB92), half Mini Card (HB92)
and USB 2.0 (AR9280+AR7010) form factors.
The AR9220 and AR9280 operate in the 2GHz and 5GHz spectra and
support 2 transmit paths and 2 receiver paths (2T2R).
The AR9223 operates in the 2GHz spectrum and supports 2
transmit paths and 2 receiver paths (2T2R).
.Pp
The AR9281 is a single-chip PCIe 802.11n solution.
It exists in PCIe Mini Card (XB91) and half Mini Card (HB91) form
factors.
It operates in the 2GHz spectrum and supports 1 transmit path and
2 receiver paths (1T2R).
.Pp
The AR9285 (codenamed Kite) is a single-chip PCIe 802.11n solution that
targets the value PC market.
It exists in PCIe half Mini Card (HB95) form factor only.
It operates in the 2GHz spectrum and supports a single stream (1T1R).
It can be combined with the AR3011 chip to form a combo WiFi/Bluetooth
device (WB195).
.Pp
The AR9271 is a single-chip USB 2.0 802.11n solution.
It operates in the 2GHz spectrum and supports a single stream (1T1R).
.Pp
The AR2427 is a single-chip PCIe 802.11b/g solution similar to the other
AR9280 solutions but with 802.11n capabilities removed.
It exists in PCIe Mini Card form factor only.
It operates in the 2GHz spectrum.
.Pp
The AR9227 and AR9287 are single-chip 802.11n solutions that
target mid-tier PCs.
The AR9227 exists in PCI and Mini-PCI form factors.
The AR9287 exists in PCIe half Mini Card (HB97)
and USB 2.0 (AR9287+AR7010) form factors.
They operate in the 2GHz spectrum and support 2 transmit paths and 2
receiver paths (2T2R).
.Pp
The following table summarizes the supported chips and their capabilities.
.Bl -column "AR9001-3NX2 (AR9160+AR9106)" "2GHz/5GHz" "3x3:3" "PCI/CardBus" -offset 6n
.It Em Chipset Ta Em Spectrum Ta Em TxR:S Ta Em Bus
.It "AR5008-2NG (AR5416+AR2122)" Ta 2GHz Ta 2x2:2 Ta PCI/CardBus
.It "AR5008-3NG (AR5416+AR2133)" Ta 2GHz Ta 3x3:2 Ta PCI/CardBus
.It "AR5008-2NX (AR5416+AR5122)" Ta 2GHz/5GHz Ta 2x2:2 Ta PCI/CardBus
.It "AR5008-3NX (AR5416+AR5133)" Ta 2GHz/5GHz Ta 3x3:2 Ta PCI/CardBus
.It "AR5008E-2NG (AR5418+AR2122)" Ta 2GHz Ta 2x2:2 Ta PCIe
.It "AR5008E-3NG (AR5418+AR2133)" Ta 2GHz Ta 3x3:2 Ta PCIe
.It "AR5008E-2NX (AR5418+AR5122)" Ta 2GHz/5GHz Ta 2x2:2 Ta PCIe
.It "AR5008E-3NX (AR5418+AR5133)" Ta 2GHz/5GHz Ta 3x3:2 Ta PCIe
.It "AR9001-2NG (AR9160+AR9103)" Ta 2GHz Ta 2x2:2 Ta PCI
.It "AR9001-3NG (AR9160+AR9103)" Ta 2GHz Ta 3x3:2 Ta PCI
.It "AR9001-3NX2 (AR9160+AR9106)" Ta 2GHz/5GHz Ta 3x3:2 Ta PCI
.It "AR9220" Ta 2GHz/5GHz Ta 2x2:2 Ta PCI
.It "AR9223" Ta 2GHz Ta 2x2:2 Ta PCI
.It "AR9280" Ta 2GHz/5GHz Ta 2x2:2 Ta PCIe
.It "AR9280+AR7010" Ta 2GHz/5GHz Ta 2x2:2 Ta USB 2.0
.It "AR9281" Ta 2GHz Ta 1x2:2 Ta PCIe
.It "AR9285" Ta 2GHz Ta 1x1:1 Ta PCIe
.It "AR9271" Ta 2GHz Ta 1x1:1 Ta USB 2.0
.It "AR2427" Ta 2GHz Ta 1x1:1 Ta PCIe
.It "AR9227" Ta 2GHz Ta 2x2:2 Ta PCI
.It "AR9287" Ta 2GHz Ta 2x2:2 Ta PCIe
.It "AR9287+AR7010" Ta 2GHz Ta 2x2:2 Ta USB 2.0
.El
.Pp
These are the modes the
.Nm
driver can operate in:
.Bl -tag -width "IBSS-masterXX"
.It BSS mode
Also known as
.Em infrastructure
mode, this is used when associating with an access point, through
which all traffic passes.
This mode is the default.
.It Host AP
In this mode the driver acts as an access point (base station)
for other cards.
.It monitor mode
In this mode the driver is able to receive packets without
associating with an access point.
This disables the internal receive filter and enables the card to
capture packets from networks which it wouldn't normally have access to,
or to scan for access points.
.El
.Pp
The
.Nm
driver can be configured to use
Wired Equivalent Privacy (WEP) or
Wi-Fi Protected Access (WPA-PSK and WPA2-PSK).
WPA is the de facto encryption standard for wireless networks.
It is strongly recommended that WEP
not be used as the sole mechanism
to secure wireless communication,
due to serious weaknesses in it.
The
.Nm
driver relies on the software 802.11 stack for both encryption and decryption
of data frames.
.\" driver offloads encryption and decryption to the hardware for the WEP40,
.\" WEP104, TKIP(+MIC) and CCMP ciphers.
.Pp
The transmit speed is user-selectable or can be adapted automatically by the
driver depending on the number of hardware transmission retries.
.Sh FILES
For USB devices, the driver needs at least version 1.1 of the following
firmware files, which are loaded when an interface is attached:
.Pp
.Bl -tag -width Ds -offset indent -compact
.It /etc/firmware/athn-ar7010
.It /etc/firmware/athn-ar7010-11
.It /etc/firmware/athn-ar9271
.El
.Pp
A prepackaged version of the firmware, designed to be used with
.Xr pkg_add 1 ,
can be found at:
.Bd -literal -offset 3n
http://firmware.openbsd.org/firmware/athn-firmware-1.1.tgz
.Ed
.Sh EXAMPLES
The following
.Xr hostname.if 5
example configures athn0 to join whatever network is available on boot,
using WEP key
.Dq 0x1deadbeef1 ,
channel 11, obtaining an IP address using DHCP:
.Bd -literal -offset indent
dhcp NONE NONE NONE nwkey 0x1deadbeef1 chan 11
.Ed
.Pp
The following
.Xr hostname.if 5
example creates a host-based access point on boot:
.Bd -literal -offset indent
inet 192.168.1.1 255.255.255.0 NONE media autoselect \e
	mediaopt hostap nwid my_net chan 11
.Ed
.Pp
Configure athn0 to join network
.Dq my_net
using WPA with passphrase
.Dq my_passphrase :
.Bd -literal -offset indent
# ifconfig athn0 nwid my_net wpakey my_passphrase
.Ed
.Pp
Join an existing BSS network,
.Dq my_net :
.Bd -literal -offset indent
# ifconfig athn0 192.168.1.1 netmask 0xffffff00 nwid my_net
.Ed
.Sh DIAGNOSTICS
.Bl -diag
.It "athn%d: device timeout"
A frame dispatched to the hardware for transmission did not complete in time.
The driver will reset the hardware.
This should not happen.
.It "athn%d: radio is disabled by hardware switch"
The radio transmitter is off and thus no packet can go out.
The driver will reset the hardware.
Make sure the laptop radio switch is on.
.It "athn%d: radio switch turned off"
The radio switch has been turned off while the interface was up and running.
The driver will turn the interface down.
.It "athn%d: error %d, could not read firmware %s"
For some reason, the driver was unable to read the firmware file from the
filesystem.
The file might be missing or corrupted.
.El
.Sh SEE ALSO
.Xr arp 4 ,
.Xr cardbus 4 ,
.Xr ifmedia 4 ,
.Xr intro 4 ,
.Xr netintro 4 ,
.Xr pci 4 ,
.Xr usb 4 ,
.Xr hostname.if 5 ,
.Xr ifconfig 8
.Sh HISTORY
The
.Nm
driver first appeared in
.Ox 4.7 .
Support for USB 2.0 devices first appeared in
.Ox 4.9 .
.Sh AUTHORS
The
.Nm
driver was written by
.An Damien Bergamini Aq damien@openbsd.org
based on source code licensed under the ISC released in 2008 by
Atheros Communications for Linux.
.Sh CAVEATS
The
.Nm
driver does not support any of the 802.11n capabilities offered by
the adapters.
Additional work is required in
.Xr ieee80211 9
before those features can be supported.
.Pp
Host AP mode doesn't support power saving.
Clients attempting to use power saving mode may experience significant
packet loss (disabling power saving on the client will fix this).