Ipw3945

Intel PRO/Wireless 3945ABG Mini-PCI Express Adapter This is a Mini-PCI Express WiFi Adapter Features Chipset: Intel WM3945AG IEEE Standards: 802.11a, 802.11b, 802.11g PCI ID: 8086:4227

IBM Partnumbers

41A4068 (From Wireless & networking accessories - ThinkPad T60/p)

NOTE!

Only the IBM Parts will work, any other parts will give an 1802 error on Post because the sub-vendor PCI ID is different, see Problem with unauthorized MiniPCI network card for more details

Also known (in IBM literature) as....

• From announcement letter 106-068, 'Intel PRO/Wireless 3945ABG8 wireless connection'

Hardware switch

Some ThinkPads have a hardware switch that must be in the on position for the radio to work, regardless of driver state:

If it is off, you might encounter following Log-Message on Startup:

 ipw3945: Radio Frequency Kill Switch is On:
 Kill switch must be turned off for wireless networking to work.

Packages

• Fedora
  • Packages: http://www.atrpms.net/dist/fc5/ipw3945
  • Helpful Thread: http://www.linuxquestions.org/questions/showthread.php?t=436357
  • ATrpms yum repo rpm: http://atrpms.net/dist/common/atrpms/atrpms-67-1.at.noarch.rpm.html
  • NOTE: The T60p uses the smp kernel which the ipw3945 yum install does not provide. You will need the smp kernel for your architecture found at http://www.atrpms.net/dist/fc5/ipw3945. Remove the non-smp kernel and replace it with the appropriate smp kernel. Wireless works great for me... --Herlo 18:06, 22 June 2006 (CEST)
• CentOS
  • Packages: ipw3945d (i386 [1] or x86_64 [2]), ipw3945-firmware.noarch, dkms-ipw3945.noarch
  • NOTE: Add to /etc/modprobe.conf: alias eth1 ipw3945
• Mandriva
  • Mandriva's kernel comes with the ipw3945 module (since at least 2006.0 Update One)
  • dkms package (dkms-ipw3945) can be found in contrib (currenlty cooker only, thus will probably be in 2007.0)
  • Additional Packages: ipw3945d and ipw3945-ucode, both either available in the commercial distribution (or club) or from http://plf.zarb.org/
• Gentoo
  • The net-wireless/ipw3945 package contains everything you need
• Debian
  • The ipw3945 microcode is available in the firmware-ipw3945 package (currently in testing and unstable (same versions)).
  • The ipw3945 regulatory daemon is available in the ipw3945d package (currently in testing and unstable (same versions)).
  • The ipw3945 module source is available in the ipw3945-source package (currently in testing and unstable (same versions)).
  • DEPRECIATED: Unofficial packages are available from Russell Stuart, Stefan Lippers-Hollmann, and Joachim Reichel.
• OpenBSD
  • Supported with the wpi driver in 4.0.
• Ubuntu
  • Works out of the box in Ubuntu 7.10 but requires Restricted repository.
• ArchLinux
  • Wireless Setup for ArchLinux

Linux WiFi driver

The most recent revision of the Intel Centrino platform utilizes a new generation of wireless networking device connected to the system via PCI-E, and not PCI (like the ipw2200-line used to do). Therefore, a new driver must be used. A sourceforge-project supporting the new cards is available at http://ipw3945.sourceforge.net/. However, as of today, the project's code (Stable Release 1.2.0) depends on a binary-only, proprietary user-space-daemon communicating with the driver via sysfs. It is not possible to operate this device with Free Software exclusively at the moment. The license-terms the daemon is released under prohibit reverse-engineering of the communication-protocol; this will hopefully not hold developers outside the US, where clauses like this one are not enforceable, from re-implementing a free variant of some sort.

There is a new project called Intel Wireless WiFi Link Drivers which seems to also implement a driver for the 3945. Those drivers are called "iwl" instead of "ipw". The iwl3945 driver already works to some extend but it still in early stage. It is full open source without binary user space things. Just a firmware blob is needed. Full documentation including source can be found on the mentioned web-page.

Since kernel 2.6.22 the new WLAN subsystem mac80211 appears. All the newer WLAN-drivers will use it.

External Discussion

This issue already sparked discussions on the Linux Kernel Mailing List, accessible via http://lkml.org/lkml/2006/2/24/266.

There is also a very revealing interview with the author of the OpenBSD driver for the 3945, in which it comes out that Intel has lied (at least by omission) about the purpose of the "regulatory daemon".

Current State

The ipw2200-drivers in kernel 2.6.15 (and possibly later) do not work with this adapter. There is no mainline-kernel support at the moment, and without a change in the license of the required user-space-daemon, or mechanics of the code itself, probably will never be any.

Some comments

ipw3945 works with http://ipw3945.sourceforge.net/ drivers. A Spanish summary, but easy to understand about how to install: esDebian Forum, maxim_o message (longer)

Thinkpad topic: on ThinkPads like the Z60 that have one. remember to put the wireless switch in the on state! But you will not be able to enable the Wireless LED with Fn+F5, it is not a problem.

One more comment: if you want monitor mode (e.g for use with Kismet or other network sniffers), you need to uncomment CONFIG_IPW3945_MONITOR=y line from ipw3945-1.1.0 Makefile.

ThinkPads this card may be found in

• T43, T43p as an external ExpressCard
• R60
• T60, T60p, T61
• X60, X60s, X60 Tablet, X61s
• Z61e, Z61m, Z61t, Z61p
• Lenovo 300