From mboxrd@z Thu Jan 1 00:00:00 1970 From: aaron lwe Subject: any way to evaluate a device's _PS0 method when its power state is at D0? Date: Thu, 19 May 2011 18:06:47 +0800 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: Received: from mail-bw0-f46.google.com ([209.85.214.46]:33596 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755380Ab1ESKGt (ORCPT ); Thu, 19 May 2011 06:06:49 -0400 Received: by bwz15 with SMTP id 15so2209920bwz.19 for ; Thu, 19 May 2011 03:06:47 -0700 (PDT) Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: linux-acpi@vger.kernel.org Hi, On init, a device's power state is set by acpi_bus_init_power, it got the information either via power_resources or via _PSC. My BIOS vendor here did this simply as follows: Device (xx) { Name (ABPS, 0) Method (_PSC, 0, NotSerialized) { Return (ABPS) } } So on init, this device's power state will be set to D0 due to ABPS is 0, but its _PS0 never get called. If later I want to evaluate its _PS0 control method, what should I do? acpi_bus_set_power will return if it found the set state is the same with the current state. Thanks, Aaron