Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751681AbcDUH4Q (ORCPT ); Thu, 21 Apr 2016 03:56:16 -0400 Received: from szxga01-in.huawei.com ([58.251.152.64]:47800 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751041AbcDUH4P (ORCPT ); Thu, 21 Apr 2016 03:56:15 -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> 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: <5718878A.8040901@huawei.com> Date: Thu, 21 Apr 2016 15:55:54 +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=0001.0A020202.5718879A.00CA,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: d19b6f9319ea386c3134a1043d38ac5d Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2457 Lines: 72 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. BRs, Kefeng [1] https://lkml.org/lkml/2016/4/5/55 > > Rob > > . >