From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dimitri Rebrikov Subject: AE_TIME on Operations in EC ( Embedded Controller ec.c ) Date: Mon, 15 Sep 2003 10:44:11 +0200 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <3F657BDB.9080805@t-systems.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Hi, after i installed 2.4.22 on my Notebook i couldn't get any battery information more. (i.e. nothing in /proc/acpi/battery) BTW. I had no problem with ACPI before (2.4.18+ACPI and 2.4.20+ACPI) The corresponding error message in log was: Sep 5 12:49:57 mitnb kernel: evregion-0345: *** Error: Handler for [EmbeddedControl] returned AE_TIME Sep 5 12:49:57 mitnb kernel: psparse-1121: *** Error: Method execution failed [\_SB_.BAT0._STA] (Node cee7cdc8), AE_TIME Other embedded controls (i.e. thermal, fan etc) were not affected by this problem. After some testing i located (i belief) the issue: The values of ACPI_EC_UDELAY_COUNT and/or ACPI_EC_UDELAY are too small for my Hardware. Here is the comparision between 2.4.20+ACPI and 2.4.22: ./linux-2.4.20/drivers/acpi/ec.c:#define ACPI_EC_UDELAY 1000 /* Poll @ 100us increments */ ./linux-2.4.20/drivers/acpi/ec.c:#define ACPI_EC_UDELAY_COUNT 10000 /* Wait 10ms max. during EC ops */ ./linux-2.4.22/drivers/acpi/ec.c:#define ACPI_EC_UDELAY 100 /* Poll @ 100us increments */ ./linux-2.4.22/drivers/acpi/ec.c:#define ACPI_EC_UDELAY_COUNT 1000 /* Wait 10ms max. during EC ops */ This means that the wait time for a EC operation in 2.4.22 was reduced with factor 100. After i increase the value of ACPI_EC_UDELAY_COUNT to 10000 my problems gone. Now i can use the whole functionality of ACPI. I don't know is there something in the ACPI specifikation defining max. wait time during EC op, or the values in ec.c was investigated by testing. My Hardware: (Clevo D270S Notebook, Pentium 4 M 1.8) http://www.clevo.com.tw/products/D220S.asp Regards Dimitri ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf