Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751271AbdCPCWj (ORCPT ); Wed, 15 Mar 2017 22:22:39 -0400 Received: from szxga03-in.huawei.com ([45.249.212.189]:4413 "EHLO dggrg03-dlp.huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1751137AbdCPCWf (ORCPT ); Wed, 15 Mar 2017 22:22:35 -0400 Subject: Re: [PATCH V7 5/7] ACPI: Delay the enumeration on the devices whose dependency has not met To: "Rafael J. Wysocki" References: <1489372963-9000-1-git-send-email-yuanzhichang@hisilicon.com> <1489372963-9000-6-git-send-email-yuanzhichang@hisilicon.com> <4600523.rWNiWKrYZC@aspire.rjw.lan> CC: , , , , , , , , , , , , , , , , , , , , , , , , From: "zhichang.yuan" Message-ID: <58C9F6C6.4090700@hisilicon.com> Date: Thu, 16 Mar 2017 10:21:58 +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: <4600523.rWNiWKrYZC@aspire.rjw.lan> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.57.79.81] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020206.58C9F6D1.018B,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: d13ba66d32df66f220852e3bf8c77419 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1327 Lines: 38 Hi, Rafael, Thanks for your review! On 2017/3/14 5:24, Rafael J. Wysocki wrote: > On Monday, March 13, 2017 10:42:41 AM zhichang.yuan wrote: >> In commit 40e7fcb1929(ACPI: Add _DEP support to fix battery issue on Asus >> T100TA), the '_DEP' was supported to solve the dependency of Asus battery. But >> this patch is specific to Asus battery device. >> In the real world, there are other devices which need the dependency to play the >> role on the enumeration order. For example, all the Hip06 LPC >> periperals(IPMI-BT, uart, etc) must be scanned after the LPC host driver >> finished the probing. So, it makes sense to add a checking whether the ACPI >> device meet all the dependencies during its enumeration slot, if not, the >> enumeration will be delayed till all dependency master finish their work. >> >> This patch adds the dependency checking in ACPI enumeration, also the >> corresponding handling to retrigger the Hip06 LPC peripherals' scanning. > > AFAICS, _DEP is generally abused in the wild and cannot be made generic. Sorry. > >From the ACPI specification, _DEP is for operation region accesses. You are right... How about we add a ACPI handler for our LPC bus?? Just like amba. In this way, we also can solve the issue about LPC enumeration order. Thanks, Zhichang > Thanks, > Rafael > > > . >