Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031385AbcCQVuP (ORCPT ); Thu, 17 Mar 2016 17:50:15 -0400 Received: from mail-lb0-f182.google.com ([209.85.217.182]:33136 "EHLO mail-lb0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935671AbcCQVuL (ORCPT ); Thu, 17 Mar 2016 17:50:11 -0400 MIME-Version: 1.0 In-Reply-To: <56EB11E2.6050608@gmail.com> References: <1458174199-23615-1-git-send-email-ddaney.cavm@gmail.com> <20160317080926.GO1793@lahna.fi.intel.com> <56EB11E2.6050608@gmail.com> Date: Thu, 17 Mar 2016 22:50:08 +0100 X-Google-Sender-Auth: heKZkaBre7J1KhYMlySaF3ve4D8 Message-ID: Subject: Re: [PATCH] ACPI / property: Export a couple of symbols. From: "Rafael J. Wysocki" To: David Daney Cc: "Rafael J. Wysocki" , Mika Westerberg , "Rafael J. Wysocki" , Len Brown , ACPI Devel Maling List , Linux Kernel Mailing List , Robert Richter , Tomasz Nowicki , David Daney Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1906 Lines: 54 On Thu, Mar 17, 2016 at 9:21 PM, David Daney wrote: > On 03/17/2016 06:00 AM, Rafael J. Wysocki wrote: >> >> On Thu, Mar 17, 2016 at 9:09 AM, Mika Westerberg >> wrote: >>> >>> On Wed, Mar 16, 2016 at 05:23:19PM -0700, David Daney wrote: >>>> >>>> From: David Daney >>>> >>>> The acpi_dev_prop_read() and acpi_dev_prop_read_single() can be called >>>> by drivers. Add EXPORT_SYMBOL_GPL to them to allow use by modular >>>> drivers. This makes them consistent with acpi_dev_get_property() and >>>> acpi_node_get_property_reference() which are already exported. >>>> >>>> Signed-off-by: David Daney >>>> --- >>>> FWIW: We hope to submit soon Cavium Thunder networking patches that >>>> fail under modular builds without these exports. >>> >>> >>> You should not be using these functions directly in drivers. >> >> >> That's exactly my point. >> > > OK, for the sake of argument I will concede that my particular use of > acpi_dev_prop_read_single() is incorrect. > > Let me ask you this: > > What is the point of the code in drivers/acpi/property.c? It is used by the code in drivers/base/property.c. > acpi_dev_prop_read() and acpi_dev_prop_read_single() are not used anywhere > that I can see in the kernel, would you accept a patch to remove them? Yes, I would. They are leftovers. > But from a philosophical point of view, what is the underlying problem of > having drivers extract property information from the ACPI tables > corresponding to the devices they control. > > Specifically, I am trying to understand how to port drivers that currently > successfully use OF device tree so that they are usable in systems with ACPI > based firmware. The code in drivers/base/property.c is for that in theory. If it doesn't work for you, please let me know what the problem is. Thanks, Rafael