On Nov 19, 2007 9:45 PM, Bob Burroughs <[EMAIL PROTECTED]> wrote:

> I don't know whether this is an appropriate thread for this
> list, but the subject problem is widespread.  This particular
> LUG probably has more IBM people--and therefore more ThinkPad
> luggers--than any other.
>
> Has anybody managed to get Gutsy to work on a ThinkPad (mine is
> a T61) with the iwp3945 driver?  I can't get wireless to work on
> this brand new, overpriced piece of hardware for more than an hour
> at a time.  Sometimes, wireless fails to come up at all.  Anybody
> know anything about this problem?


I do in fact have a Thinkpad using the ipw3945 driver.  Can't say that you
calling it overpriced is terribly endearing, but we'll chalk that one up to
frustration.  For a long time wireless was a bit questionable for me but
things have settled down recently.  I installed ipw3945, compiled against
Gentoo's suspend2 version of several different 2.6.X kernels, I think from
the 2.6.19 or earlier, up through 2.6.22.  It works pretty well.

The two biggest problems I have encountered with the wireless are: sometimes
eth1 isn't what it thinks it is, and sometimes the wireless does not want to
associate.  The first one is an easy fix.  Apparently, there is a very deep
power save feature in the Thinkpad BIOS that turns off the wired LAN port
when it is not in use, but it's tuned a bit too aggressively and it will
occasionally turn off before the kernel sees the port.  The kernel reports
something about an invalid EPROM checksum and does not initialize the port
correctly.  This will hose networking, and the simplest solution is to plug
in a cat-5 when you boot; it can be removed immediately after boot and using
suspend makes this less of an issue because the port only needs to be on
when the driver initializes.  I believe you can also unload e1000, plug
something in, and modprobe it back in.  More work, but faster and more
convenient.  You can also comment out the checksum check in the e1000
driver, but let's just say that's not the best idea.

The second issue is a little stranger.  I have found that sometimes even
though iwconfig reports all the correct information, I can't associate with
an AP (iwconfig will say "unassociated" next to the AP line).  This only
seems to happen when changing between APs.  I wish I had a better answer,
but my solution is usually a combo of unloading/reloading the driver and
running "iwpriv eth1 reset && iwconfig eth1 ap any && iwconfig eth1 channel
<the_right_one>."  I'm not sure why it gets "stuck" like that, but sometimes
it just needs a bit of a kick in the pants.

I have never seen it only work for a short period of time and then drop.
All of my wireless problems occur before I get an IP address; after that
it's rock solid.

-Jay
_______________________________________________
Mid-Hudson Valley Linux Users Group                  http://mhvlug.org          
   
http://mhvlug.org/cgi-bin/mailman/listinfo/mhvlug                           
Upcoming Meetings (6pm - 8pm)                         MHVLS Auditorium          
                              
  Oct 3 - Security and Privacy
  Nov 7 - Django Python Application Framework

Reply via email to