Bug 3974 - BATTERY state incorrect - okay in 2.4 - on Compaq Presario
BATTERY state incorrect - okay in 2.4 - on Compaq Presario
Product: ACPI
Classification: Unclassified
Component: Power-Battery
i386 Linux
: P2 normal
Assigned To: Luming Yu
: 5048 (view as bug list)
Depends on:
  Show dependency treegraph
Reported: 2004-12-31 02:27 UTC by Matthew East
Modified: 2007-07-12 17:19 UTC (History)
5 users (show)

See Also:
Kernel Version: 2.6.9
Tree: Mainline
Regression: ---

Output from acpidmp (113.17 KB, text/plain)
2005-01-03 22:36 UTC, Matthew East
Output of dmesg (15.12 KB, text/plain)
2005-01-03 22:38 UTC, Matthew East
Output from dmesg (21.93 KB, text/plain)
2005-01-09 03:47 UTC, Matthew East
dmesg output, baier (12.78 KB, text/plain)
2005-05-18 12:10 UTC, Norman Urs Baier
output of acpidmp, baier (95.61 KB, text/plain)
2005-05-18 12:11 UTC, Norman Urs Baier
dmidecode output, baier (5.33 KB, text/plain)
2005-05-18 12:15 UTC, Norman Urs Baier
lspci output (9.86 KB, text/plain)
2005-05-18 12:17 UTC, Norman Urs Baier
interrupts as in /proc/interrupts, baier (566 bytes, text/plain)
2005-05-18 12:19 UTC, Norman Urs Baier

Description Matthew East 2004-12-31 02:27:57 UTC
Since 2.6.9 kernel I have experienced problems with the battery state
on my Compaq Presario 2104EA laptop. I have noticed the problem when
running the ubuntu kernel, which I believe is patched with a
recent acpi release, and the gentoo-dev-sources 2.6.9. I just
installed a 2.4.26 kernel, and have found that it works perfectly.

The problems are quite difficult to describe. Essentially when i boot with the
power adapter plugged in, acpid will give me the correct reading of
the battery. When there is a CHANGE of AC adapter state (i.e. i unplug
it), acpid does not give me the correct battery status, which remains
at the level which it was at. The same problem happens if I start the
computer without AC power, and plug it in: in this case the battery
status begins to go down correctly, but when AC is inserted, the level does not
go up as it should.

AFAICS the AC state is read correctly, and everything else (thermal etc) seems fine.

The results when I tested it with the 2.4 kernel have convinced me
that this is not a hardware problem.

I would be happy to provide any more information, and I hope i've been clear.

Many thanks in advance for your help.


Distribution: Gentoo
Hardware Environment: Compaq Presario 2104EA
Software Environment:
Problem Description:

Steps to reproduce:
Comment 1 Len Brown 2005-01-03 21:37:00 UTC
please attach the output from dmesg -s64000 and the output
from acpidmp, found in /usr/sbin, or in pmtools here:
Comment 2 Matthew East 2005-01-03 22:36:45 UTC
Created attachment 4333 [details]
Output from acpidmp

Attached as request the output from acpidmp.
Comment 3 Matthew East 2005-01-03 22:38:22 UTC
Created attachment 4334 [details]
Output of dmesg

As requested, output from dmesg -s 64000. However there is a problem: I'm
pretty sure this is not long enough for your needs, i.e. does not go all the
way back. I don't know how to make it longer. If you let me know, i'll do my

thanks, Matt
Comment 4 Matthew East 2005-01-09 03:47:10 UTC
Created attachment 4357 [details]
Output from dmesg

Have recompiled my kernel with a bigger buffer size, so now here is the whole
of dmesg. Hope this helps, and that this problem can be tracked down.
Comment 5 Norman Urs Baier 2005-05-18 12:08:04 UTC
I experience the same problems, first I suspected the BIOS is at fault, but a 
well known commercial operative system does not show the same symptoms. 
I am using a kernel on a Pentium-M 745/ICH-4 Laptop (Littlebit Razor 
I will try to attach the different logs... 
Comment 6 Norman Urs Baier 2005-05-18 12:10:11 UTC
Created attachment 5071 [details]
dmesg output, baier
Comment 7 Norman Urs Baier 2005-05-18 12:11:24 UTC
Created attachment 5072 [details]
output of acpidmp, baier
Comment 8 Norman Urs Baier 2005-05-18 12:15:56 UTC
Created attachment 5073 [details]
dmidecode output, baier
Comment 9 Norman Urs Baier 2005-05-18 12:17:37 UTC
Created attachment 5074 [details]
lspci output
Comment 10 Norman Urs Baier 2005-05-18 12:19:22 UTC
Created attachment 5075 [details]
interrupts as in /proc/interrupts, baier
Comment 11 Shaohua 2005-05-18 17:36:55 UTC
This possibly is the EC issue. Please try the latest -mm tree, which includes 
the burst mode EC read/write patch.
Comment 12 Norman Urs Baier 2005-05-21 15:04:30 UTC
I don't know about Mathew East, but at least in my case acpi info is much vivid 
with kernel rc4-mm2. Hope the relevant patch gets rapidly integrated into 
stable, such that swsusp2 patch applies cleanly again... 
Comment 13 Matthew East 2005-06-28 15:40:16 UTC
I still have this problem: no battery status. Recently I installed Windows to
ensure this wasn't a hardware problem: works fine. I've been without battery
status since 2.6.9 :/
Comment 14 Matthew East 2005-08-19 06:12:33 UTC
I still have this problem with the current Ubuntu unstable kernel (2.6.12 plus
Ubuntu patches). I was thinking that perhaps it would help to try an unstable
kernel: could you point me to a kernel that I can try to see if this problem is
solved in your latest development tree?

I'm really keen to sort this problem out because being without battery status is
a huge blocker for me!

Comment 15 Luming Yu 2005-08-19 06:26:44 UTC
Could you try linux-2.6.13 with patch filed at bug 3851 (id: 5574)
Please try  both burst_mode=0 and burst_mode=1
Comment 16 Matthew East 2005-08-19 13:44:04 UTC
ok I've downloaded that kernel and have applied that patch, it's building now so
I will let you know. I'm not sure how to set burst_mode=0/1 however: I can
compile a kernel but I am not very knowledgeable about how it works!

Comment 17 Matthew East 2005-08-20 01:50:54 UTC
Ok I booted that kernel but I did not have any battery status changes: I booted
up with AC power enabled, then took the plug out: no change in battery status.


Comment 18 Luming Yu 2005-08-20 02:46:20 UTC
boot kernel with option: ec_burst=1 
Comment 19 Matthew East 2005-08-20 05:57:32 UTC
Yes, that fixes it! It also fixes my inability to change the screen brightness,
which i noted in Ubuntu bugzilla here:

Thanks for your help! Will this patch be available in the stable kernel soon?
Comment 20 Luming Yu 2005-08-21 00:11:45 UTC
*** Bug 3516 has been marked as a duplicate of this bug. ***
Comment 21 Luming Yu 2005-08-21 19:27:24 UTC
*** Bug 5048 has been marked as a duplicate of this bug. ***
Comment 22 Len Brown 2007-03-07 22:41:30 UTC
Does Linux-2.6.20 work without any cmdline parameters?
Comment 23 Adrian Bunk 2007-07-12 17:19:28 UTC
Please reopen this bug if it's still present with kernel 2.6.22.

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