From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753550AbbAENkW (ORCPT ); Mon, 5 Jan 2015 08:40:22 -0500 Received: from mga02.intel.com ([134.134.136.20]:50437 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752923AbbAENkU (ORCPT ); Mon, 5 Jan 2015 08:40:20 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="436599469" Date: Mon, 5 Jan 2015 15:40:10 +0200 From: Mika Westerberg To: "Rafael J. Wysocki" Cc: ACPI Devel Maling List , Linux PM list , Linux Kernel Mailing List Subject: Re: [PATCH] ACPI / PM: Fix PM initialization for devices that are not present Message-ID: <20150105134010.GF1386@lahna.fi.intel.com> References: <4453924.d7c5RYZUJi@vostro.rjw.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4453924.d7c5RYZUJi@vostro.rjw.lan> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 01, 2015 at 11:38:28PM +0100, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > If an ACPI device object whose _STA returns 0 (not present and not > functional) has _PR0 or _PS0, its power_manageable flag will be set > and acpi_bus_init_power() will return 0 for it. Consequently, if > such a device object is passed to the ACPI device PM functions, they > will attempt to carry out the requested operation on the device, > although they should not do that for devices that are not present. > > To fix that problem make acpi_bus_init_power() return an error code > for devices that are not present which will cause power_manageable to > be cleared for them as appropriate in acpi_bus_get_power_flags(). > However, the lists of power resources should not be freed for the > device in that case, so modify acpi_bus_get_power_flags() to keep > those lists even if acpi_bus_init_power() returns an error. > Accordingly, when deciding whether or not the lists of power > resources need to be freed, acpi_free_power_resources_lists() > should check the power.flags.power_resources flag instead of > flags.power_manageable, so make that change too. > > Furthermore, if acpi_bus_attach() sees that flags.initialized is > unset for the given device, it should reset the power management > settings of the device and re-initialize them from scratch instead > of relying on the previous settings (the device may have appeared > after being not present previously, for example), so make it use > the 'valid' flag of the D0 power state as the initial value of > flags.power_manageable for it and call acpi_bus_init_power() to > discover its current power state. > > Signed-off-by: Rafael J. Wysocki Reviewed-by: Mika Westerberg