C3 and C4 can't be reached. powertop doesn't show C3 and C4.

[ubuntu_demon]

C3 and C4 can't be reached. powertop doesn't show C3 and C4.

There's no related BIOS option as far as I can see.

I'm running Gutsy fully updated and installed from Tribe 3.

powertop package version : 1.7~svn-r227-1

#uname -a
Linux T-2500 2.6.22-8-generic #1 SMP Thu Jul 12 15:59:45 GMT 2007 i686 GNU/Linux

#cd /var/lib/acpi-support/ ; grep . -r *-*
bios-version:1.01
system-manufacturer:American Megatrends Inc
system-product-name:M31EI Series

some installed kernel packages (dpkg -l) :
ii linux-generic 2.6.22.8.8 Complete Generic Linux kernel
ii linux-headers-2.6.22-8 2.6.22-8.18 Header files related to Linux kernel version
ii linux-headers-2.6.22-8-generic 2.6.22-8.18 Linux kernel headers for version 2.6.22 on x
ii linux-headers-generic 2.6.22.8.8 Generic Linux kernel headers
ii linux-image-2.6.22-8-generic 2.6.22-8.18 Linux kernel image for version 2.6.22 on x86
ii linux-image-generic 2.6.22.8.8 Generic Linux kernel image
ii linux-restricted-modules-2.6.22-8-generic 2.6.22.2-8.4 Non-free Linux 2.6.22 modules on x86/x86_64
ii linux-restricted-modules-common 2.6.22.2-8.4 Non-free Linux 2.6.22 modules helper script
ii linux-restricted-modules-generic 2.6.22.8.8 Restricted Linux modules for generic kernels
ii linux-ubuntu-modules-2.6.22-8-generic 2.6.22-8.20 Ubuntu supplied Linux modules for version 2.
ii powertop 1.7~svn-r227-1 linux tool to find out what is using power o

my laptop (the page is a bit outdated) : https://wiki.ubuntu.com/LaptopTestingTeam/AhtecStyleX30Duo

[ubuntu_demon (ubuntu-demon)]

I think this bug is related to my hardware. I'm wondering whether other people experience the same.

[ubuntu_demon (ubuntu-demon)]

With "related to my hardware" I meant the combination of bios, hardware and linux kernel

[ubuntu_demon (ubuntu-demon)]

More information about my system in this bug report (also from today) :
https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.22/+bug/129224

Any other information needed ?

[ubuntu_demon (ubuntu-demon)]

My cpu : Intel Core Duo T2500

(posted from Feisty)

[unggnu (unggnu)]

I have the same problem but only with connected ac adapter. In battery mode I can see both modes and they are used.

[Henrik Nilsen Omma (henrik)]

Thanks for testing and providing debugging output. Confirming.

[ubuntu_demon (ubuntu-demon)]

my hardware does support C3/C4 (intel Core Duo T2500). Is there anything else I should provide to make debugging this problem easier ?

[ubuntu_demon (ubuntu-demon)]

This also affects hardy :
Linux ubuntu 2.6.24-16-generic #1 SMP Thu Apr 10 13:23:42 UTC 2008 i686 GNU/Linux

[Kjell Braden (afflux)]

The source package for the kernel has changed to just "linux" since hardy. Changed the affected package.

[Leann Ogasawara (leannogasawara)]

Care to confirm this is still an issue with the latest Alpha for the upcoming Intrepid Ibex 8.10 . More information regarding the latest Alpha can be found at http://www.ubuntu.com/testing. Please let us know your results.

We'll keep this report open against the actively developed kernel bug against 2.6.22 this will be closed as it does not qualify for a Stable Release Update - http://wiki.ubuntu.com/StableReleaseUpdates . Thanks.

[Leann Ogasawara (leannogasawara)]

The Ubuntu Kernel Team is planning to move to the 2.6.27 kernel for the upcoming Intrepid Ibex 8.10 release. As a result, the kernel team would appreciate it if you could please test this newer 2.6.27 Ubuntu kernel. There are one of two ways you should be able to test:

1) If you are comfortable installing packages on your own, the linux-image-2.6.27-* package is currently available for you to install and test.

--or--

2) The upcoming Alpha5 for Intrepid Ibex 8.10 will contain this newer 2.6.27 Ubuntu kernel. Alpha5 is set to be released Thursday Sept 4. Please watch http://www.ubuntu.com/testing for Alpha5 to be announced. You should then be able to test via a LiveCD.

Please let us know immediately if this newer 2.6.27 kernel resolves the bug reported here or if the issue remains. More importantly, please open a new bug report for each new bug/regression introduced by the 2.6.27 kernel and tag the bug report with 'linux-2.6.27'. Also, please specifically note if the issue does or does not appear in the 2.6.26 kernel. Thanks again, we really appreicate your help and feedback.

[Jose Bernardo (bernardo-bandos)]

On a Acer Aspire One, with 2.6.27-4, C4 isn't visible and seems no to be used, even though the Atom cpu has C4/C4E support.

[Jose Bernardo (bernardo-bandos)]

Forgot to add that powertop does show C3 state if running on battery.

[Launchpad Janitor (janitor)]

Per a decision made by the Ubuntu Kernel Team, bugs will longer be assigned to the ubuntu-kernel-team in Launchpad as part of the bug triage process. The ubuntu-kernel-team is being unassigned from this bug report. Refer to https://wiki.ubuntu.com/KernelTeamBugPolicies for more information. Thanks.

[Bryan Wu (cooloney)]

This bug report is being closed because we received no response to the previous inquiry for information. Please reopen if this is still an issue in the current Ubuntu release, Jaunty Jackalope 9.04 - http://www.ubuntu.com/getubuntu/download. If the issue remains in Jaunty, please test the latest upstream kernel build - https://wiki.ubuntu.com/KernelMainlineBuilds . To reopen the bug, click on the current status under the Status column and change the status back to "New". Thanks.