From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751432AbcBMWQg (ORCPT ); Sat, 13 Feb 2016 17:16:36 -0500 Received: from mail.ispras.ru ([83.149.199.45]:53395 "EHLO mail.ispras.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750961AbcBMWQe (ORCPT ); Sat, 13 Feb 2016 17:16:34 -0500 Subject: Re: [PATCH] i2c: designware: balance clk enable/disable on removal To: Wolfram Sang , Andy Shevchenko References: <1454106696-5867-1-git-send-email-khoroshilov@ispras.ru> <56AF69D3.4070300@linux.intel.com> <1454337845.32507.20.camel@linux.intel.com> <20160212185400.GH1520@katana> Cc: Jarkko Nikula , Mika Westerberg , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org From: Alexey Khoroshilov X-Enigmail-Draft-Status: N1010 Message-ID: <56BFAB3F.7080607@ispras.ru> Date: Sun, 14 Feb 2016 01:16:31 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20160212185400.GH1520@katana> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12.02.2016 21:54, Wolfram Sang wrote: > On Mon, Feb 01, 2016 at 04:44:05PM +0200, Andy Shevchenko wrote: >> On Mon, 2016-02-01 at 16:21 +0200, Jarkko Nikula wrote: >>> On 01/30/2016 12:31 AM, Alexey Khoroshilov wrote: >>>> It seems clk_disable_unprepare() is missed in dw_i2c_plat_remove(), >>>> so the patch adds it. >>>> >>>> Found by Linux Driver Verification project (linuxtesting.org). >>>> >>>> Signed-off-by: Alexey Khoroshilov >>>> --- >>>> drivers/i2c/busses/i2c-designware-platdrv.c | 1 + >>>> 1 file changed, 1 insertion(+) >>>> >>>> diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c >>>> b/drivers/i2c/busses/i2c-designware-platdrv.c >>>> index 438f1b4964c0..8f19b7b81fe0 100644 >>>> --- a/drivers/i2c/busses/i2c-designware-platdrv.c >>>> +++ b/drivers/i2c/busses/i2c-designware-platdrv.c >>>> @@ -267,6 +267,7 @@ static int dw_i2c_plat_remove(struct >>>> platform_device *pdev) >>>> i2c_del_adapter(&dev->adapter); >>>> >>>> i2c_dw_disable(dev); >>>> + i2c_dw_plat_prepare_clk(dev, false); >>>> >>> I tried this quickly and it appears more work is needed. When >>> CONFIG_PM_SLEEP is set then autosuspending will do the unprepare and >>> this patch causes double unprepare at remove. But when >>> CONFIG_PM_SLEEP >>> is not set then indeed those clk calls are out of sync. >> >> Besides that I would suggest to check carefully error patch in the >> probe(), i.e. handling error from i2c_dw_probe(). There maybe similar >> issue is hidden. > > So, waiting for V2 on this one. > I have a fix for error handling of i2c_dw_probe(), but I am not sure what is the right approach to handle CONFIG_PM_SLEEP case. What is a safe way to distinguish a need for the unprepare in dw_i2c_plat_remove()? Should we try to avoid double i2c_dw_disable(dev) in the same case? -- Alexey