From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753944AbcHQIFl (ORCPT ); Wed, 17 Aug 2016 04:05:41 -0400 Received: from mga11.intel.com ([192.55.52.93]:49217 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753849AbcHQIFh (ORCPT ); Wed, 17 Aug 2016 04:05:37 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,529,1464678000"; d="scan'208";a="1026846315" Subject: Re: [PATCH v3 2/3] i2c: designware: detect when dynamic tar update is possible To: "De Marchi, Lucas" , "linux-i2c@vger.kernel.org" References: <1469743424-2480-1-git-send-email-lucas.demarchi@intel.com> <1469743424-2480-3-git-send-email-lucas.demarchi@intel.com> <1471356468.2907.4.camel@intel.com> Cc: "mika.westerberg@linux.intel.com" , "linux-kernel@vger.kernel.org" , "christian.ruppert@alitech.com" , "Souza, Jose" From: Jarkko Nikula Message-ID: Date: Wed, 17 Aug 2016 11:05:34 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.2.0 MIME-Version: 1.0 In-Reply-To: <1471356468.2907.4.camel@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/16/2016 05:07 PM, De Marchi, Lucas wrote: > On Tue, 2016-08-16 at 17:00 +0300, Jarkko Nikula wrote: >>> + */ >>> + reg = dw_readl(dev, DW_IC_CON); >>> + dw_writel(dev, reg ^ DW_IC_CON_10BITADDR_MASTER, >>> DW_IC_CON); >>> + >>> + if ((dw_readl(dev, DW_IC_CON) & >>> DW_IC_CON_10BITADDR_MASTER) == >>> + (reg & DW_IC_CON_10BITADDR_MASTER)) { >>> + dev->dynamic_tar_update_enabled = true; >>> + dev_dbg(dev->dev, "Dynamic TAR update enabled"); >>> + } >> >> Is this possible to move to i2c_dw_probe()? I guess the enabled >> status >> doesn't change runtime? > > It was actually useful at this place during development of this patch > because we could check any unexpected change in behavior when resuming. > We did catch a bug because of this and fixed. > I'm not sure if now it makes more sense to move to probe method. I'd > leave it where it is, but I'm open to move it there. > Can you do a quick re-test that case to see does it change runtime? If it does then this needs a comment why there is need to do this check each time when HW is reinitialized. Otherwise there is chance someone may move this code to probe time in the future. -- Jarkko