Difference between revisions of "Ipw2200"

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See {{path|README.ipw2200}} in the <tt>ipw2200</tt> package for details and other options.
 
See {{path|README.ipw2200}} in the <tt>ipw2200</tt> package for details and other options.
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== wpa_supplicant assigns a random SSID wasting power ==
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Many wpa_supplicant versions implement disconnection by configuring a random SSID. ipw2200 reacts in a very unfortunate way to this, intensively scanning for this random SSID and wasting power. This waste can be seen in powertop.
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Here are a number of ways to solve this problem:
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* Run <tt>iwconfig eth1 essid off</tt> after every wpa_supplicant disconnection.
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* Upgrade to wpa_supplicant version 0.7.1 or higher. Starting from git commit 3145e615 wpa_supplicant does not configure ipw2200 with a random SSID any more.
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* Backporting commit 3145e615 to wpa_supplicant version 0.6.8 also fixes the problem.
  
 
== Changing the enabled channels ==
 
== Changing the enabled channels ==
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{{WARN|If this procedure goes wrong, you may ruin your wireless card.}}
 
{{WARN|If this procedure goes wrong, you may ruin your wireless card.}}
 
== wpa_supplicant assigns a random SSID which wastes power ==
 
 
Many wpa_supplicant versions implement disconnection by configuring a random SSID. The ipw2200 reacts in a very unfortunate way to this, intensively scanning for this random SSID and wasting power. This waste can be seen in powertop.
 
 
Here are a number of ways to solve this problem:
 
* Run <tt>iwconfig eth1 essid off</tt> after every wpa_supplicant disconnection.
 
* Upgrade to wpa_supplicant version 0.7.1 or higher. Starting from git commit 3145e615 wpa_supplicant does not configure ipw2200 with a random SSID any more.
 
* Backporting commit 3145e615 to wpa_supplicant version 0.6.8 also fixes the problem.
 
 
  
 
== Additional Comments ==
 
== Additional Comments ==

Latest revision as of 11:29, 18 November 2010

The Ipw2200 is the Linux driver for the Intel PRO/Wireless 2200BG Mini-PCI Adapter and Intel PRO/Wireless 2915ABG Mini-PCI Adapter found in Centrino laptops. This driver only works on 2.6.x kernels (2.6.4 or newer).

Starting with kernels 2.6.14 the driver is included in kernel.

NOTE!
Make sure you have installed the firmware! The ipw2200 documentation will tell you where to find these firmware files and where to install those.

Included in mainline Linux kernels, tracking the SourceForge version with about 6 months delay.

Packages

  • Fedora Packages(1): Fedora Core includes the ipw2200-drivers in FC3 (with updates) and FC4. You still need to grab the firmware from http://rpm.livna.org/
  • Fedora Packages(2): http://www.atrpms.net/name/ipw2200/
  • Mandriva: The ipw2200 driver modules are included in the stock kernel package; the firmware is included in the commercial distribution or available from http://plf.zarb.org/.
  • Gentoo: The driver is in the portage tree: emerge net-wireless/ipw2200 and net-wireless/ipw2200-firmware
  • Debian Sarge includes the source code for the modules in package ipw2200-source (http://packages.debian.org/ipw2200-source). You additionally need to download firmware manually.
  • Debian Etch includes a version of the modules in its kernel or for a later version install package ipw2200-modules-2.6-486 or ipw2200-modules-2.6-686 or ipw2200-modules-2.6-686-bigmem or ipw2200-modules-2.6-k7 or ipw2200-modules-2.6-amd64; or the source code for them in ipw2200-source (http://packages.debian.org/ipw2200-source) to compile one yourself. You additionally need to download firmware manually.

Status

In development, usable, WEP 128bit encryption works, WPA and WPA2 work with drivers >= 1.0.2 using wpa_supplicant, monitor/rfmon is supported as with version >= 1.0.6. Generally works well, but some users experience problems (especially with firmware restarts and with WPA functionality using wpa_supplicant). Passing the hwcrypto=0 module parameter improves reliability for many users.

The ipw2200 driver up to version 1.0.6 (in combination with some newer kernels) had a problem getting DHCP leases (it turned out to be a bug in the broadcasting code). Version 1.0.7 seems to have fixed this.

Older ipw2200 driver versions shipped by many distributions have been reported to freeze a T43 after several minutes of intensive communication. Installing version 1.1.2 of the driver solved the problem.

Latest stable versions:

  • ipw2200 driver: 1.2.0
  • firmware: 3.0
  • ieee80211 stack: 1.2.15

Latest development versions:

  • ipw2200 driver: 1.2.2
  • firmware: 3.1
  • ieee80211 stack: 1.2.18

Mainline kernels contain older (but mostly functional) versions of ipw2200 and ieee80211, and still require the addition of the firmware files. To get the latest versions you need to separately install the ipw2200 module and ieee80211 stack.

Installation

Source Code

Download the latest ieee80211 stack and install it:

# tar xzvf ieee80211-1.2.15.tgz
# cd ieee80211-1.2.15
# make
# make install

Download the latest ipw2200 module and install it:

# tar xzvf ipw2200-1.2.0.tgz
# cd ipw2200-1.2.0
# make
# make install

Download the matching firmware and install it:

# tar xzvf ipw2200-fw-3.1.tgz -C /lib/firmware

Debian Sarge

# apt-get install ipw2200-source

# module-assistant -t build ipw2200-source

[is this how module-assistant works in Sarge?]

Debian Etch

The kernel includes a version but if you want a more recent version install the module ipw2200-modules-2.6-486 or ipw2200-modules-2.6-686 or ipw2200-modules-2.6-686-bigmem or ipw2200-modules-2.6-k7 or ipw2200-modules-2.6-amd64 depending on your architecture.

The firmware is not distributed with Debian due to licensing reasons, download the matching version 3.0 firmware and install it:

# tar -xvf ipw2200-fw-3.1.tgz -C /lib/firmware
# mv /lib/firmware/ipw2200-fw-3.1/* /lib/firmware

Debian Unstable

Install ieee80211-source:

# apt-get install ieee80211-source
# module-assistant -t build ieee80211-source

The kernel includes a version but if you want a more recent version install the module ipw2200-modules-2.6-486 or ipw2200-modules-2.6-686 or ipw2200-modules-2.6-686-bigmem or ipw2200-modules-2.6-k7 or ipw2200-modules-2.6-amd64 depending on your architecture.

There is a bug in the Debian package (last checked: Dec 30th 2005) that prevents from linking to ieee80211 modules using module-assistant. In case it is not fixed in your version, fall back to the regular source installation procedure described above.

The firmware is not distributed with Debian due to licensing reasons, download the matching firmware and install it:

# tar xzvf ipw2200-fw-2.4.tgz -C /usr/lib/hotplug/firmware

see /etc/hotplug/firmware.agent for details on configured firmware locations

Make sure that your firmware files are not in a subdirectory (dmesg will give you warnings after any modprobe when firmware can't be loaded)

Fedora Core

Installation on Fedora Core 5 works out of the box provided you install the ipw2200-firmware package. However, certain parts of the install process may not set up the wireless networking in a friendly manner using GNOME system tray icons and other tools. Bill Moss has written some excellent HowTo articles, including using VPNC to connect to a remote Cisco IPSec network.

Testing the driver

# modprobe ipw2200
# iwconfig

# dmesg output might look similar to this:

ieee80211: 802.11 data/management/control stack, 1.1.6
ieee80211: Copyright (C) 2004-2005 Intel Corporation <jketreno@linux.intel.com>
ipw2200: Intel(R) PRO/Wireless 2200/2915 Network Driver, 1.0.8
ipw2200: Copyright(c) 2003-2005 Intel Corporation
ipw2200: Detected Intel PRO/Wireless 2915ABG Network Connection

NB: To make the wifi LED work on the thinkpad, pass the option led=1 to the kernel while loading the module. eg. # modprobe ipw2200 led=1. This can also be accomplished by adding that option to the file where your distribution looks for modprobe options so that it becomes automatic.

In debian this can be done by putting a file named after the module in /etc/modutils with the options in it

here we might run a cmd like this

# echo options ipw2200 led=1 > /etc/modutils/ipw2200

then we must run update-modules to remake /etc/module.conf

# update-modules

WPA support

Use wpa_supplicant with the -Dwext argument (not -Dipw), and pass the hwcrypto=0 argument to the ipw2200 module.

There are some very detailed instructions with working sample configurations on the following link: ipw2200 WPA instruction

Power Management

The ipw2200 driver has power management capabilities, which comes in handy while operating on battery.

To enable reduced power consumption mode, issue:

# iwpriv wlan0 set_power 7

where wlan0 is the name of your interface. This will reduce idle power consumption by 1-2 Watts compared to no power management. To return to the "normal" operation mode, you can issue:

# iwpriv wlan0 set_power 6.

In order to check current settings, you can issue:

# iwpriv wlan0 get_power.

More information on these option is available in the README.ipw3945 file in the ipw3945 package (README.ipw2200 seems to be rather sketchy about the details of power management). You may want to turn power management on/off on demand in an ACPI script that catches battery/AC events, so that this happens automatically.

Note that there have been reports that some versions of ipw2200 react with a firmware error to power management commands. This patch could alleviate the problem.

  • To disable the radio (and further reduce power consumption) when the card is not in use, issue:
# echo 1 > /sys/bus/pci/drivers/ipw2200/*/rf_kill
  • To enable the radio, issue:
# echo 0 > /sys/bus/pci/drivers/ipw2200/*/rf_kill
  • To make the radio off by default after boot, add
options ipw2200 disable=1

to your /etc/modprobe.conf or equivalent (on kubuntu 6.10 /etc/modprobe.d/options).

See README.ipw2200 in the ipw2200 package for details and other options.

wpa_supplicant assigns a random SSID wasting power

Many wpa_supplicant versions implement disconnection by configuring a random SSID. ipw2200 reacts in a very unfortunate way to this, intensively scanning for this random SSID and wasting power. This waste can be seen in powertop.

Here are a number of ways to solve this problem:

  • Run iwconfig eth1 essid off after every wpa_supplicant disconnection.
  • Upgrade to wpa_supplicant version 0.7.1 or higher. Starting from git commit 3145e615 wpa_supplicant does not configure ipw2200 with a random SSID any more.
  • Backporting commit 3145e615 to wpa_supplicant version 0.6.8 also fixes the problem.

Changing the enabled channels

Permitted WiFi channels vary with geography due to regulation. The EEPROM in this chip contains a country code (programmed by the hardware manufacturer), and the driver converts this to a channel list and enforces it.

If you carry your laptop to a different regulatory region, you may need to change the list of permitted channels according to local regulations. There are two ways to accomplish this:

Patching the ipw2200 driver

You can alter the ipw2200 driver sourcecode to hard-code the country code instead of reading it from EEPROM. For example, this will allow all 14 channels (perfect for those special occasions in international water):

--- ipw2200.c.orig
+++ ipw2200.c
@@ -11344,7 +11344,7 @@ static int ipw_up(struct ipw_priv *priv)
 		memcpy(priv->net_dev->dev_addr, priv->mac_addr, ETH_ALEN);
 
 		for (j = 0; j < ARRAY_SIZE(ipw_geos); j++) {
-			if (!memcmp(&priv->eeprom[EEPROM_COUNTRY_CODE],
+			if (!memcmp("ZZR",
 				    ipw_geos[j].name, 3))
 				break;
 		}

For the list of codes and their meaning, see the "ipw_geos" table in the ipw2200.c sourcecode.

Patching the EEPROM

Alternatively, you can change the country code in the EEPROM once and for all, and then use the standard ipw2200 driver.

See this guide:

Instead of the hd program mentioned there, you can use the more common od program:

echo -n ZZD | od -t x1
0000000 5a 5a 44
0000003
ATTENTION!
If this procedure goes wrong, you may ruin your wireless card.

Additional Comments

Your kernel may include an old version of the ipw2200 driver. It is recommended to use the latest version.

Make sure you also install the firmware version needed by the driver version you use. You can find the firmware here. To install it, decompress the .tgz file into /usr/lib/hotplug/firmware or /lib/firmware depending on your disto.

The driver doesn't appear to support the MII interface, so any tools like automatic network configuration managers (i.e. whereami) that rely on mii-tool do not work.

See incompatibility with some Access Points described on this other page

External links