Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752031AbcDUIXp (ORCPT ); Thu, 21 Apr 2016 04:23:45 -0400 Received: from mx0b-0016f401.pphosted.com ([67.231.156.173]:48055 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751618AbcDUIXn (ORCPT ); Thu, 21 Apr 2016 04:23:43 -0400 Date: Thu, 21 Apr 2016 16:19:22 +0800 From: Jisheng Zhang To: Jarkko Nikula CC: Andy Shevchenko , , , , , Subject: Re: [PATCH 2/4] i2c: designware-platdrv: fix unbalanced clk enable and prepare Message-ID: <20160421161922.0068ef51@xhacker> In-Reply-To: <571883C6.3010404@linux.intel.com> References: <1460638414-5987-1-git-send-email-jszhang@marvell.com> <1460638414-5987-3-git-send-email-jszhang@marvell.com> <57177C32.4090000@linux.intel.com> <1461161760.6620.306.camel@linux.intel.com> <20160421104022.2d6549a9@xhacker> <571883C6.3010404@linux.intel.com> X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-04-21_06:,, signatures=0 X-Proofpoint-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1603290000 definitions=main-1604210136 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1319 Lines: 35 Dear Jarkko, On Thu, 21 Apr 2016 10:39:50 +0300 Jarkko Nikula wrote: > On 04/21/2016 05:40 AM, Jisheng Zhang wrote: > > Dear Jarkko, Andy, > > > > On Wed, 20 Apr 2016 17:16:00 +0300 Andy Shevchenko wrote: > > > >> On Wed, 2016-04-20 at 15:55 +0300, Jarkko Nikula wrote: > >>> I see Andy's 1cb715ca4694 ("i2c-designware: move to managed functions > >>> (devm_*)") removed it but at quick look drivers/clk/clk-devres.c: > >>> devm_clk_release() calls only clk_put and I don't see disable is done > >>> down the path. > >> > >> The following is a mistake of the mentioned patch. > >> - clk_disable_unprepare(dev->clk); > >> > >> I did at the same mistake in dw_dmac driver which had been fixed later > >> in the commit 8be4f523b480 ("dmaengine: dw: fix regression in dw_probe() > >> function"). > >> > > > > As Andy pointed out, managed devm_clk_get can only automatically put clk > > but doesn't unprepare and disable the clk > > > Ok, then it makes sense to move this fix first in the series and queue > for stable v4.5+. Then another from you, Andy or me for kernels before > b33af11de236 ("i2c: designware: Do not require clock when SSCN and FFCN > are provided") that introduced the i2c_dw_plat_prepare_clk(). Sounds a good idea. Will send a separate fix for this purpose soon. Thanks, Jisheng