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=-15.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 0B439C433EF for ; Wed, 15 Sep 2021 18:31:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E5BF360EE9 for ; Wed, 15 Sep 2021 18:31:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229718AbhIOScw (ORCPT ); Wed, 15 Sep 2021 14:32:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60024 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229466AbhIOScv (ORCPT ); Wed, 15 Sep 2021 14:32:51 -0400 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CAFD2C061574; Wed, 15 Sep 2021 11:31:32 -0700 (PDT) Received: by mail-pj1-x102c.google.com with SMTP id j1so2739614pjv.3; Wed, 15 Sep 2021 11:31:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=subject:from:to:cc:references:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=08DeS9EiRSwxDI4M4feIzMG6iv/hhxkj2trxtcVNueQ=; b=Isi3v0awJAXImI6JZWmC2kzZ2bkcEcvasEWWr1Uwi7NiCeP1wfXBbJyVpuoNNsT83w 9G3l42sCUrp77DZ8jyzZ66n3ectwAAYzhrpHdrta/QUXVwpVvOvpBD+ex10WXp3547D5 dYzYd+llFo3ThINzmwFJjHDKFJ8ZT1gVZA85RaEgFQig0FG+hncm7Ds2IGHfQfXyzKry hL7+FVZ68T7LQZ0PkhY5CNGH46poBUWWUMfD7Xn1ZtqIBkZFxdlmLd6HKN78ivbF8Sbd AjvhNQ4yjsQ00LoIP3uwA25RKdcMFKevf1GwgqNKMTJplhV5+rnPgl13Iy9CtTeb/T+O mEfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:subject:from:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=08DeS9EiRSwxDI4M4feIzMG6iv/hhxkj2trxtcVNueQ=; b=wSj7ozeKkv3JwozN0N04h5F/DSrrHfxR8jGp7Ov+qmIeEleweX1Nf3VLg68FZXAOlG m4RVnHrIKCsao2ggektZgf51z4zg8iwwhV8EUHK2rUBBzEgD3txKbmNR8/pg5s9V2I1c x2FKaneENuug52pu5buLcOKYW+jpQDkVTCuC+2CF9yM9UUsp1Jn6JCNuiWF2/DWYwZB9 ltnvYXyppzoe0v+tUQQhNy9WmFiuzuu8Zku5V3fz/OIU3UnsKRqorrPTMdtxYAwm3/GQ luhd86/qXLrV4Jml258eHwTgE6ZA0TyjYTXtD4rlSSAWd8Tum96gUbEamwxDxqsHn7er or3g== X-Gm-Message-State: AOAM530unkEbjcZjbYWlTPgxpIk1J049yajOO0FX03Vbi48B+27SOYGf sHpjhVdMsJtwcSqmm5fvm29+TNCb3AH1gg== X-Google-Smtp-Source: ABdhPJy5KgIo85Vx7NQj8y/nMacZJHdmDudSZt0KB1Xp/n7LV+TMPprGRN6sVBeMfcqm6mepY5u9hg== X-Received: by 2002:a17:90b:1c0c:: with SMTP id oc12mr7891665pjb.45.1631730691859; Wed, 15 Sep 2021 11:31:31 -0700 (PDT) Received: from [172.30.1.2] ([14.32.163.5]) by smtp.gmail.com with ESMTPSA id s192sm657273pgc.23.2021.09.15.11.31.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 15 Sep 2021 11:31:31 -0700 (PDT) Subject: Re: [PATCH v1 4/4] PM / devfreq: tegra30: Check whether clk_round_rate() returns zero rate From: Chanwoo Choi To: Dmitry Osipenko , Thierry Reding , Jonathan Hunter , Viresh Kumar , Nishanth Menon , MyungJoo Ham , Stephen Boyd , Kyungmin Park , Chanwoo Choi Cc: linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org References: <20210912184458.17995-1-digetx@gmail.com> <20210912184458.17995-5-digetx@gmail.com> <9fa66405-883a-3653-eb5d-3cd7eee07a0a@gmail.com> Message-ID: Date: Thu, 16 Sep 2021 03:31:26 +0900 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <9fa66405-883a-3653-eb5d-3cd7eee07a0a@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 21. 9. 15. 오후 12:51, Chanwoo Choi wrote: > Hi, > > On 21. 9. 13. 오전 3:44, Dmitry Osipenko wrote: >> EMC clock is always-on and can't be zero. Check whether clk_round_rate() >> returns zero rate and error out if it does. It can return zero if clock >> tree isn't initialized properly. >> >> Signed-off-by: Dmitry Osipenko >> --- >>   drivers/devfreq/tegra30-devfreq.c | 4 ++-- >>   1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/devfreq/tegra30-devfreq.c >> b/drivers/devfreq/tegra30-devfreq.c >> index d83fdc2713ed..65ecf17a36f4 100644 >> --- a/drivers/devfreq/tegra30-devfreq.c >> +++ b/drivers/devfreq/tegra30-devfreq.c >> @@ -891,9 +891,9 @@ static int tegra_devfreq_probe(struct >> platform_device *pdev) >>           return err; >>       rate = clk_round_rate(tegra->emc_clock, ULONG_MAX); >> -    if (rate < 0) { >> +    if (rate <= 0) { >>           dev_err(&pdev->dev, "Failed to round clock rate: %ld\n", rate); >> -        return rate; >> +        return rate ?: -EINVAL; If rate is 0, It doesn't return and fall-through? even if print the error message. 'return rate ?: -EINVAL;' style is strange for me because it doesn't specify the 'return value' when rate is true. -- Best Regards, Samsung Electronics Chanwoo Choi