Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753320AbcDVCsM (ORCPT ); Thu, 21 Apr 2016 22:48:12 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:54383 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751863AbcDVCsK (ORCPT ); Thu, 21 Apr 2016 22:48:10 -0400 Subject: Re: [PATCH v2 all 00/14] use of_platform_default_populate() to populate default bus To: Rob Herring References: <1458113743-15131-1-git-send-email-wangkefeng.wang@huawei.com> <5718878A.8040901@huawei.com> CC: "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Arnd Bergmann , Shawn Guo , Catalin Marinas , "Russell King - ARM Linux" , Grant Likely , Olof Johansson , Masahiro Yamada , Hanjun Guo From: Kefeng Wang Message-ID: <571990C4.7000901@huawei.com> Date: Fri, 22 Apr 2016 10:47:32 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.19.180] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020202.571990DE.00C3,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: a3de12694da9879235335e254b60a4b6 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2919 Lines: 80 On 2016/4/21 21:10, Rob Herring wrote: > On Thu, Apr 21, 2016 at 2:55 AM, Kefeng Wang wrote: >> Hi Rob, >> >> On 2016/4/20 5:10, Rob Herring wrote: >>> On Wed, Mar 16, 2016 at 2:35 AM, Kefeng Wang wrote: >>>> Use helper of_platform_default_populate() in linux/of_platform >>>> when possible, instead of calling of_platform_populate() with >>>> the default match table. >>>> >>>> Then it is possible for driver code build as a module, and no >>>> need to export of_default_bus_match_table anymore. >>>> >>>> This patchset is based on Linux 4.5. >>>> >>>> Changes since v1: >>>> - Add ack, test and review >>>> - Remove v1 patch 14/15, the similar patch has posted and applied, >>>> see https://patchwork.kernel.org/patch/8096991/ >>>> >>>> v1: >>>> - https://lkml.org/lkml/2016/1/26/1123 >>> >>> I was going to apply this, but I've thought about this some more and >>> it is a lot of tree wide churn for little gain. Most of the call sites >>> here I want to get rid of by making of_platform_populate callable >>> multiple times. The infrastructure is almost there, but I think we >>> just need something like this: >>> >>> diff --git a/drivers/of/platform.c b/drivers/of/platform.c >>> index 8d103e4..b25e710 100644 >>> --- a/drivers/of/platform.c >>> +++ b/drivers/of/platform.c >>> @@ -345,6 +345,9 @@ static int of_platform_bus_create(struct device_node *bus, >>> return 0; >>> } >>> >>> + if (of_node_check_flag(bus, OF_POPULATED_BUS)) >>> + return 0; >>> + >>> auxdata = of_dev_lookup(lookup, bus); >>> if (auxdata) { >>> bus_id = auxdata->name; >>> >>> Then we can call of_platform_populate from the DT core and remove all >>> the default calls. >> >> OK, it seems that we can drop all the of_of_platform_default_populate in arch code >> by this changes, will do it. >> >> But replace of_platform_populate() with the default match table by of_platform_default_populate >> is a cleanup, and especially for the driver, we can not need export of_default_bus_match_table >> after that. >> >> There is a v3 patchset[1], it is based 4.6-rc2 with some updated, should this be merge firstly, >> then drop all the default of_platform_populate in arch code, and I think the of_iommu_init() in >> arch code could do the same thing. >> >> If not, I will repost the patches with new ways, but still exists the part of unexport >> of_default_bus_match_table by helper of_platform_default_populate(). >> >> Hope the v3 patchset could be merge in advance, after all, it has been reviewed fully. Thanks a lot. > > We'd be touching the same line twice in a bunch of places if we apply > this series first, so it makes more sense to remove all these calls > first and then use of_platform_default_populate where it is still > needed. Agree, will repost them. BRs, Kefeng > > Rob > > . >