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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 29E1FE7D0A2 for ; Thu, 21 Sep 2023 20:58:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232057AbjIUU6n (ORCPT ); Thu, 21 Sep 2023 16:58:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232166AbjIUU6F (ORCPT ); Thu, 21 Sep 2023 16:58:05 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53E4D7EA0E for ; Thu, 21 Sep 2023 10:37:35 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6DEA6C32798; Thu, 21 Sep 2023 10:37:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695292675; bh=l3altaqa2vlkLvvlLcemsJXO+aays1kdpxDpG0qkff4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=IHKYggjbKElo1leuZD7jc0VoseeE94G/G1cDa+fVm2V6TwbnoGiZFBvtloGDnQoAw rfcE2rDFoMlO4FQRpThrm+jetlms/D+UqUa7D0ZkESklLhmjfNsT33v6RkPJjs53vK Txd30i7dADjW3NDyOiIQDSA32EWFDpuTg2Rv7nYE2A5l8eSWZvA53oPKfgl8NueTfj GB8FRoQ2ytxlaVoumfjcPY1mPsqHrQ9XoaGJvCOJLQAMNqLgml348f0HK+MgXdZBaY TztDIH4cRZSNv3X/nHQd2xiDpllTkbPGfUkbL3o7+Vb8iTWVAr6jI/TrP5hKUkn0r7 RVpD0obEbWfbA== Date: Thu, 21 Sep 2023 11:37:51 +0100 From: Lee Jones To: Stephen Zhang Cc: linux-kernel@vger.kernel.org, zhangshida@kylinos.cn, k2ci Subject: Re: [PATCH] mfd: cs42l43: fix defined but not used warnings Message-ID: <20230921103751.GD3449785@google.com> References: <20230905021209.1412987-1-zhangshida@kylinos.cn> <20230920095248.GC13143@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 21 Sep 2023, Stephen Zhang wrote: > Lee Jones 于2023年9月20日周三 17:52写道： > > > > On Tue, 05 Sep 2023, zhangshida wrote: > > > > > From: Shida Zhang > > > > > > Warnings were generated during compiling for functions like > > > cs42l43_*_{resume,suspend}: > > > > > > ../drivers/mfd/cs42l43.c:1138:12: error: ‘cs42l43_runtime_resume’ defined but not used [-Werror=unused-function] > > > 1138 | static int cs42l43_runtime_resume(struct device *dev) > > > | ^~~~~~~~~~~~~~~~~~~~~~ > > > ../drivers/mfd/cs42l43.c:1124:12: error: ‘cs42l43_runtime_suspend’ defined but not used [-Werror=unused-function] > > > 1124 | static int cs42l43_runtime_suspend(struct device *dev) > > > | ^~~~~~~~~~~~~~~~~~~~~~~ > > > ../drivers/mfd/cs42l43.c:1106:12: error: ‘cs42l43_resume’ defined but not used [-Werror=unused-function] > > > 1106 | static int cs42l43_resume(struct device *dev) > > > | ^~~~~~~~~~~~~~ > > > ../drivers/mfd/cs42l43.c:1076:12: error: ‘cs42l43_suspend’ defined but not used [-Werror=unused-function] > > > 1076 | static int cs42l43_suspend(struct device *dev) > > > > > > Fix it by guarding it with CONFIG_PM/CONFIG_PM_SLEEP. > > > > > > Reported-by: k2ci > > > Signed-off-by: Shida Zhang > > > --- > > > drivers/mfd/cs42l43.c | 4 ++++ > > > 1 file changed, 4 insertions(+) > > > > > > diff --git a/drivers/mfd/cs42l43.c b/drivers/mfd/cs42l43.c > > > index 37b23e9bae82..e589a61c118d 100644 > > > --- a/drivers/mfd/cs42l43.c > > > +++ b/drivers/mfd/cs42l43.c > > > @@ -1073,6 +1073,7 @@ void cs42l43_dev_remove(struct cs42l43 *cs42l43) > > > } > > > EXPORT_SYMBOL_NS_GPL(cs42l43_dev_remove, MFD_CS42L43); > > > > > > +#ifdef CONFIG_PM_SLEEP > > > static int cs42l43_suspend(struct device *dev) > > > { > > > struct cs42l43 *cs42l43 = dev_get_drvdata(dev); > > > @@ -1120,7 +1121,9 @@ static int cs42l43_resume(struct device *dev) > > > > > > return 0; > > > } > > > +#endif > > > > > > +#ifdef CONFIG_PM > > > static int cs42l43_runtime_suspend(struct device *dev) > > > { > > > struct cs42l43 *cs42l43 = dev_get_drvdata(dev); > > > @@ -1176,6 +1179,7 @@ static int cs42l43_runtime_resume(struct device *dev) > > > > > > return ret; > > > } > > > +#endif > > > > > > EXPORT_NS_GPL_DEV_PM_OPS(cs42l43_pm_ops, MFD_CS42L43) = { > > > SET_SYSTEM_SLEEP_PM_OPS(cs42l43_suspend, cs42l43_resume) > > > > I see a bunch of drivers using PM helpers and not many of them are > > are being guarded by ugly #ifery. Please find out what they're doing to > > solve the same issue and replicate that instead. > > > > Here's a really big hint: > > > > `git log --oneline 02313a90095fb` > > > > Thanks, I've learned something from the hint. > > And I also checked the code: > ----- > EXPORT_NS_GPL_DEV_PM_OPS(cs42l43_pm_ops, MFD_CS42L43) = { > SET_SYSTEM_SLEEP_PM_OPS(cs42l43_suspend, cs42l43_resume) > SET_RUNTIME_PM_OPS(cs42l43_runtime_suspend, > cs42l43_runtime_resume, NULL) > }; > ---- > #ifdef CONFIG_PM_SLEEP > #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \ > SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) > #else > #define SET_SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) > #endif > ---- > #define SYSTEM_SLEEP_PM_OPS(suspend_fn, resume_fn) \ > .suspend = pm_sleep_ptr(suspend_fn), \ > .resume = pm_sleep_ptr(resume_fn), \ > .freeze = pm_sleep_ptr(suspend_fn), \ > .thaw = pm_sleep_ptr(resume_fn), \ > .poweroff = pm_sleep_ptr(suspend_fn), \ > .restore = pm_sleep_ptr(resume_fn), > ---- > The technique has already been used by the marcos, but it still > reports the defined-but-not-used warning. The MACROS can use #ifery since they are located in header files. #ifery in C files is to be avoided if at all possible. > Maybe some compilers still choose to compile these functions in... > Anyway, I will just leave it alone since it is really not a big problem... If you're seeing an error, it should be fixed. Why is this not an issue anywhere else? Does the same build complain about all the other drivers too? -- Lee Jones [李琼斯]