From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753705AbcHQAcr (ORCPT ); Tue, 16 Aug 2016 20:32:47 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:45281 "HELO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752922AbcHQAcp (ORCPT ); Tue, 16 Aug 2016 20:32:45 -0400 From: "Rafael J. Wysocki" To: Lukas Wunner Cc: linux-efi@vger.kernel.org, Matt Fleming , linux-kernel@vger.kernel.org, Andreas Noever , Pierre Moreau , Aleksey Makarov , "Rafael J. Wysocki" , linux-acpi@vger.kernel.org Subject: Re: [PATCH 2/6] ACPI / bus: Make acpi_get_first_physical_node() public Date: Wed, 17 Aug 2016 02:38:15 +0200 Message-ID: <1821462.QyPXGhZaWJ@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/4.8.0-rc1+; KDE/4.11.5; x86_64; ; ) In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday, July 28, 2016 02:25:41 AM Lukas Wunner wrote: > Following the fwnode of a device is currently a one-way road: We provide > ACPI_COMPANION() to obtain the fwnode but there's no (public) method to > do the reverse. Granted, there may be multiple physical_nodes, but often > the first one in the list is sufficient. > > A handy function to obtain it was introduced with commit 3b95bd160547 > ("ACPI: introduce a function to find the first physical device"), but > currently it's only available internally. > > We're about to add an EFI Device Path parser which needs this function. > Consider the following device path: ACPI(PNP0A03,0)/PCI(28,2)/PCI(0,0) > The PCI root is encoded as an ACPI device in the path, so the parser > has to find the corresponding ACPI device, then find its physical node, > find the PCI bridge in slot 1c (decimal 28), function 2 below it and > finally find the PCI device in slot 0, function 0. > > To this end, make acpi_get_first_physical_node() public. > > Cc: Aleksey Makarov > Cc: Rafael J. Wysocki > Signed-off-by: Lukas Wunner ACK Thanks, Rafael