ThinkPad - UltraBay battery magic

[Dan Langille]

On 17 Jun 2006 at 20:39, Kevin Oberman wrote:

> > From: "Dan Langille" <dan at langille.org>
> > Date: Sat, 17 Jun 2006 21:08:54 -0400
> > 
> > On 17 Jun 2006 at 16:54, Kevin Oberman wrote:
> > 
> > > > When installing a 2nd battery (i.e in the UltraBay after removing the 
> > > > CD drive) in a ThinkPad, I think there's some magic you must invoke 
> > > > to get the system to notice the additional power resource.
> > > > 
> > > > Any ideas?
> > > 
> > > The code to allow ACPI to add batteries has yet to be written (or committed, 
> > > at least). If the system is booted with 2 two batteries, both will be seen. 
> > > Even it one is removed and then returned, it will be seen. But if a system is 
> > > booted with a single battery, ACPI will not ever see the second battery.
> > > 
> > > Please note that the second battery WILL be seen by the hardware and both 
> > > charged and used.
> > 
> > I rebooted.  It froze after probing ad0.  I powered off.  I removed 
> > the spare battery. I rebooted.  Froze again, same place.  I put in 
> > the CD drive, it booted fine.  I swapped out the CD drive and put the 
> > battery back in.  This time I did a verbose boot.
> > 
> > In short:
> > both batteries are seen in the probing.
> > ad0 is probed
> > pcm0 is measured
> > fdc0: output ready timeout
> > [repeat above line 7 times]
> > GEOM: new disk ad0
> > 
> > Screen shot here:
> > 
> >   http://www.langille.org/tmp/100_2831.jpg
> > 
> > Ideas? Suggestions?
> 
> This is sounding just a bit familiar. Do you actually have a floppy
> drive? If so, try putting a disk into it. If not, try building a kernel
> without the floppy and see if that behaves.

There is no floppy in this laptop (IBM ThinkPad T41); I have one, but 
it is external, connected via USD, and has not been attached during 
these tests.

I created a kernel without fd, based on GENERIC:

$ diff GENERIC LAPTOPGENNOFD1
25c25
< ident         GENERIC
---
> ident         LAPTOPGEN
159c159
< #device               apm
---
> device                apm

In short, I changed the ident, and added apm.

This kernel boots if the CDRW is installed.  Without it, the systems 
boots and then freezes at the login prompt.  I have no idea why.  The 
freeze occurs with or without the second battery.  With the CDRW 
installed, all is well.

> There have been several similar reports. You might want to look at the
> archives.

I didn't find anything that gave me a lead to follow.

-- 
Dan Langille : Software Developer looking for work
my resume: http://www.freebsddiary.org/dan_langille.php