From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A61D0C433DF for ; Tue, 26 May 2020 08:34:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 77C8F2071A for ; Tue, 26 May 2020 08:34:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=st.com header.i=@st.com header.b="P36yH9zY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731533AbgEZIec (ORCPT ); Tue, 26 May 2020 04:34:32 -0400 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:8590 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726926AbgEZIeb (ORCPT ); Tue, 26 May 2020 04:34:31 -0400 Received: from pps.filterd (m0046037.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 04Q8W2Kg031881; Tue, 26 May 2020 10:34:03 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=st.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=STMicroelectronics; bh=yYl7Q366t3wZdeT76gK6DolbnJ3PwezvlVa6m3FkDpQ=; b=P36yH9zYjirIl4Biz2lMPmtVJE18A0S4HPyvfBZfeoXnNCWdio7rZ53MIu+yq2voOYZw Ca186l1OP+6shHNyXcxEB6SUfHhwI9YLq/ZXu//ji2WFjuFFfwGnzoOjphA0QX9g7ifZ 6wYhrP2xzb3XI6AoOygPfT2/z0EyO+BDIpcyPk+1n6duOVcxbBtkeZ8UdfKEphhuwBij ZIyg0uGSU00QuCxX2NUPdLWep3cw1xqlH3OLaZKsFI+6mOEJbOYggFgYVacxHvBgUedR q4sV3L9AYofZuUef9udwp0HCyS9rvLEf7tfXnRPE3EEdAi49XknmsrwuVdssiv/bgQN8 LQ== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 316skw6hv7-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 26 May 2020 10:34:03 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 31FC410002A; Tue, 26 May 2020 10:34:02 +0200 (CEST) Received: from Webmail-eu.st.com (sfhdag3node2.st.com [10.75.127.8]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 203162BE22E; Tue, 26 May 2020 10:34:02 +0200 (CEST) Received: from gnbcxd0016.gnb.st.com (10.75.127.50) by SFHDAG3NODE2.st.com (10.75.127.8) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Tue, 26 May 2020 10:34:01 +0200 Date: Tue, 26 May 2020 10:34:00 +0200 From: Alain Volmat To: Dinghao Liu CC: , Pierre-Yves MORDRET , Maxime Coquelin , Alexandre Torgue , , , , Subject: Re: [PATCH] i2c: stm32f7: Fix runtime PM imbalance in stm32f7_i2c_reg_slave Message-ID: <20200526083400.GC10725@gnbcxd0016.gnb.st.com> Mail-Followup-To: Dinghao Liu , kjlu@umn.edu, Pierre-Yves MORDRET , Maxime Coquelin , Alexandre Torgue , linux-i2c@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20200521070507.13015-1-dinghao.liu@zju.edu.cn> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20200521070507.13015-1-dinghao.liu@zju.edu.cn> X-Disclaimer: ce message est personnel / this message is private X-Originating-IP: [10.75.127.50] X-ClientProxiedBy: SFHDAG1NODE2.st.com (10.75.127.2) To SFHDAG3NODE2.st.com (10.75.127.8) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216,18.0.687 definitions=2020-05-25_12:2020-05-25,2020-05-25 signatures=0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Dinghao, Thanks for the patch. Indeed, this should be fixed. Overall, there are several other calls to pm_runtime_get_sync within this driver, would you like to fix them all at once ? On Thu, May 21, 2020 at 03:05:07PM +0800, Dinghao Liu wrote: > pm_runtime_get_sync() increments the runtime PM usage counter even > the call returns an error code. Thus a pairing decrement is needed > on the error handling path to keep the counter balanced. > > Signed-off-by: Dinghao Liu > --- > drivers/i2c/busses/i2c-stm32f7.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c > index 330ffed011e0..602cf35649c8 100644 > --- a/drivers/i2c/busses/i2c-stm32f7.c > +++ b/drivers/i2c/busses/i2c-stm32f7.c > @@ -1767,8 +1767,10 @@ static int stm32f7_i2c_reg_slave(struct i2c_client *slave) > return ret; > > ret = pm_runtime_get_sync(dev); > - if (ret < 0) > + if (ret < 0) { > + pm_runtime_put_autosuspend(dev); Considering that if we fail here there is a very good chance that this is due to the resume failing, pm_runtime_put_noidle would probably make more sense since pm_runtime_put_autosuspend will most probably fail as well. > return ret; > + } > > if (!stm32f7_i2c_is_slave_registered(i2c_dev)) > stm32f7_i2c_enable_wakeup(i2c_dev, true); > -- > 2.17.1 >