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=-8.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 E50E1C31E4B for ; Fri, 14 Jun 2019 16:46:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BDF18217F9 for ; Fri, 14 Jun 2019 16:46:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nuer/Aob" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726786AbfFNQqO (ORCPT ); Fri, 14 Jun 2019 12:46:14 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:38206 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726244AbfFNQqM (ORCPT ); Fri, 14 Jun 2019 12:46:12 -0400 Received: by mail-pl1-f193.google.com with SMTP id f97so1251479plb.5; Fri, 14 Jun 2019 09:46:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=z0Q8djqHX6ZMfWsK/PWD8i+5lV9BAONQ6vZFum0/x6M=; b=nuer/AobPoxP8KxkPKIEp1Pi4bj1OThodc7YnaduLgelE+l0GQKCmRr/yADUxqFazs 0MRyGpcxmigz70ZivLMmBCV6QlSBJG62YKtUaJBR8SPq1dyA6a9S3vHpY4ZWGeJYGahV SS9P7gw0joJ2q1FzO3NgGsPLKXcAHByLH0zCm5nfIj1mLtB28XB2dbZoU/iV1QEx0dDr byc+3Eu0tePDzDCYi/ymYIFFeWVsn+r5y1rCOS/cZeAlHm6EVrf0Qx5PD1ZsePldomuX QaR1i58UD4J29VBGZOA03DeCsZWcJpMLKqJtBdYJqynWj5tVoSNODXu52nRsqYNPIjdW fg2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=z0Q8djqHX6ZMfWsK/PWD8i+5lV9BAONQ6vZFum0/x6M=; b=nlnqebnGwFhCnaLNnwjYg/5z7Miw+/nqJr1I8fwRTiJ0EAXbIVRaAYayyy/1ZgOysT DAsLNUWI4RHQwdSii4fccps/xmjsdgZUW2DNfKotozrY4KCxyoUgcpe3bKygKpUamF9q cVhL3NH1LEfx+kj/VXIIlT5HeOW1BOlopKnM1SFWySi6DHGSajYw7KT/Ci3nZ5Fv/xyI U9+BlhbUxaXrfrgaCVt7titsBnX8pq2vJ2LBeQyZLAZmQbD6vs20Vk+pL1wDpocRVOTc bbu6NJihJUeanCMsedvxycfBfd4ZcJFisaN2t5scVuOjErPEpCPzM/jME0iS6+3/IjaJ ChOA== X-Gm-Message-State: APjAAAVSDPz92uvWJg2w6vYCTbN+Dim9O8HxsF08mPein0f1NMW9s27s AFlQVNaP1X6z2ucn2tnWvic= X-Google-Smtp-Source: APXvYqwz29BHb+7kecHv8rdqjLtchfGJlP2LhtF80HB0TpaLtUPO64PROcPKpcZVRwui3EO+D5ubyw== X-Received: by 2002:a17:902:988b:: with SMTP id s11mr67503607plp.216.1560530771670; Fri, 14 Jun 2019 09:46:11 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id 139sm3433474pfw.152.2019.06.14.09.46.09 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 14 Jun 2019 09:46:10 -0700 (PDT) Date: Fri, 14 Jun 2019 09:46:09 -0700 From: Guenter Roeck To: Ken Sloat Cc: "nicolas.ferre@microchip.com" , "alexandre.belloni@bootlin.com" , "ludovic.desroches@microchip.com" , "wim@linux-watchdog.org" , "linux-arm-kernel@lists.infradead.org" , "linux-watchdog@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v2 1/1] watchdog: atmel: atmel-sama5d4-wdt: Disable watchdog on system suspend Message-ID: <20190614164609.GA29814@roeck-us.net> References: <20190614125310.29458-1-ksloat@aampglobal.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190614125310.29458-1-ksloat@aampglobal.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 14, 2019 at 12:53:22PM +0000, Ken Sloat wrote: > From: Ken Sloat > > Currently, the atmel-sama5d4-wdt continues to run after system suspend. > Unless the system resumes within the watchdog timeout period so the > userspace can kick it, the system will be reset. This change disables > the watchdog on suspend if it is active and re-enables on resume. These > actions occur during the late and early phases of suspend and resume > respectively to minimize chances where a lock could occur while the > watchdog is disabled. > > Signed-off-by: Ken Sloat > --- > Changes in v2: > -Consolidate resume and resume early statements. > > drivers/watchdog/sama5d4_wdt.c | 21 ++++++++++++++++++--- > 1 file changed, 18 insertions(+), 3 deletions(-) > > diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c > index 111695223aae..0d123f8cbcc6 100644 > --- a/drivers/watchdog/sama5d4_wdt.c > +++ b/drivers/watchdog/sama5d4_wdt.c > @@ -280,7 +280,17 @@ static const struct of_device_id sama5d4_wdt_of_match[] = { > MODULE_DEVICE_TABLE(of, sama5d4_wdt_of_match); > > #ifdef CONFIG_PM_SLEEP > -static int sama5d4_wdt_resume(struct device *dev) > +static int sama5d4_wdt_suspend_late(struct device *dev) > +{ > + struct sama5d4_wdt *wdt = dev_get_drvdata(dev); > + > + if (watchdog_active(&wdt->wdd)) > + sama5d4_wdt_stop(&wdt->wdd); > + > + return 0; > +} > + > +static int sama5d4_wdt_resume_early(struct device *dev) > { > struct sama5d4_wdt *wdt = dev_get_drvdata(dev); > > @@ -291,12 +301,17 @@ static int sama5d4_wdt_resume(struct device *dev) > */ > sama5d4_wdt_init(wdt); > > + if (watchdog_active(&wdt->wdd)) > + sama5d4_wdt_start(&wdt->wdd); > + The call to sama5d4_wdt_init() above now explicitly stops the watchdog even if we want to (re)start it. I think this would be better handled with an else case here else sama5d4_wdt_stop(&wdt->wdd); Guenter > return 0; > } > #endif > > -static SIMPLE_DEV_PM_OPS(sama5d4_wdt_pm_ops, NULL, > - sama5d4_wdt_resume); > +static const struct dev_pm_ops sama5d4_wdt_pm_ops = { > + SET_LATE_SYSTEM_SLEEP_PM_OPS(sama5d4_wdt_suspend_late, > + sama5d4_wdt_resume_early) > +}; > > static struct platform_driver sama5d4_wdt_driver = { > .probe = sama5d4_wdt_probe, > -- > 2.17.1 >