From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rich Townsend Subject: Re: end-user support: Battery alarm Date: Thu, 10 Mar 2005 14:31:48 -0500 Message-ID: <4230A0A4.40705@bartol.udel.edu> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit In-Reply-To: Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Mirko Hessel-von Molo Cc: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Mirko Hessel-von Molo wrote: > Dear all, > > I have a probably stupid question for which I couldn't find the > answer anywhere else. > > Is it true that a 'battery' event is raised by the kernel when the > 'current capacity' given in /proc/acpi/battery/BAT0/state goes below > the limit defined in /proc/acpi/battery/BAT0/alarm? > > I'm trying to use the battery alarm to make my system warn the user > and shutdown, if necessary. > > My setup is the following: I'm using a Dell Latitude D800 with BIOS A07, > running under Linux with Kernel 2.6.7 (not the latest one, I know). > As I 'organically evolved' the system from a RedHat 7.3 base install, > I'm reluctant to upgrade to some distro which provides acpi support. > > So far, I got pretty much everything to work, ac_adapter and battery events > are raised when the power supply changes. However, no event is > raised when the battery capacity goes below the warn level. I can't remember > where I have read this, but somehow I got the idea that this should be the > case. > > Does anyone have an idea where my problem could be? > Yes; I've no doubt that this is due to a broken DSDT. Unless Dell has put something in the DSDT that causes periodic polling of the battery level, there is no way a notification will be sent when the battery passes the trip point. There is certainly nothing in the Linux kernel that handles the polling. cheers, Rich ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click