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 9952EC433F5 for ; Sun, 6 Mar 2022 15:12:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233676AbiCFPNQ convert rfc822-to-8bit (ORCPT ); Sun, 6 Mar 2022 10:13:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39656 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229541AbiCFPNO (ORCPT ); Sun, 6 Mar 2022 10:13:14 -0500 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF1B62B257 for ; Sun, 6 Mar 2022 07:12:21 -0800 (PST) Received: from fraeml735-chm.china.huawei.com (unknown [172.18.147.226]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4KBQ5c2hkdz67gtM; Sun, 6 Mar 2022 23:11:00 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml735-chm.china.huawei.com (10.206.15.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 6 Mar 2022 16:12:19 +0100 Received: from localhost (10.47.64.190) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Sun, 6 Mar 2022 15:12:18 +0000 Date: Sun, 6 Mar 2022 15:12:12 +0000 From: Jonathan Cameron To: Paul Cercueil CC: Arnd Bergmann , Randy Dunlap , "Linux Kernel Mailing List" , Wei WANG , Kai-Heng Feng , "Greg Kroah-Hartman" , "Rafael J. Wysocki" , Subject: Re: [PATCH -next] misc: rtsx: fix build for CONFIG_PM not set Message-ID: <20220306151212.00003e6f@Huawei.com> In-Reply-To: <7U5Z7R.RNKITPUWCPX32@crapouillou.net> References: <20220226222457.13668-1-rdunlap@infradead.org> <449d6ceb-7308-9543-c23c-831bebffda21@infradead.org> <0D5Z7R.NUOWBMRT4GQ2@crapouillou.net> <7U5Z7R.RNKITPUWCPX32@crapouillou.net> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.29; i686-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 8BIT X-Originating-IP: [10.47.64.190] X-ClientProxiedBy: lhreml745-chm.china.huawei.com (10.201.108.195) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 27 Feb 2022 17:56:31 +0000 Paul Cercueil wrote: > Le dim., févr. 27 2022 at 18:51:38 +0100, Arnd Bergmann > a écrit : > > On Sun, Feb 27, 2022 at 6:46 PM Paul Cercueil > > wrote: > >> Le dim., févr. 27 2022 at 18:30:16 +0100, Arnd Bergmann > >> > >> There could be a DEFINE_DEV_PM_OPS(), but I don't think that's > >> really > >> needed - you can very well declare your struct dev_pm_ops without > >> using > >> one of these macros. Just make sure to use the SYSTEM_SLEEP_PM_OPS / > >> RUNTIME_PM_OPS macros for the callbacks and pm_ptr() for the > >> device.pm > >> pointer. > > > > Ah, of course, so it comes down to > > s/SET_SYSTEM_SLEEP_PM_OPS/SYSTEM_SLEEP_PM_OPS/ while > > removing all the #ifdef an __maybe_unused annotations. The pm_ptr() > > in driver.pm makes this slightly more optimized AFAICT, but has no > > effect on behavior, right? > > The use of SYSTEM_SLEEP_PM_OPS makes sure that the callbacks are > dropped if the dev_pm_ops is dead code, and the pm_ptr() must be used > for the compiler to know that the dev_pm_ops is dead code. > > -Paul > > Hi Paul, We have one remaining case which is still ugly to do. Where both SYSTEM_SLEEP_PM_OPS/RUNTIME_PM_OPS are set and the dev_pm_ops structure is exported. For that one we still need to expose #ifdef fun in the drivers I think. Any suggestions on a clean solution for that? Currently I have this... #ifdef CONFIG_PM const struct dev_pm_ops bmc150_magn_pm_ops = { SYSTEM_SLEEP_PM_OPS(...) RUNTIME_PM_OPS(...) }; EXPORT_SYMBOL_NS(bmc150_magn_pm_ops, IIO_BMC150_MAGN); #else static const __maybe_unused dev_pm_ops bmc150_magn_pm_ops = { SYSTEM_SLEEP_PM_OPS(...) RUNTIME_PM_OPS(...) }; #endif Not super clean but perhaps we do need EXPORT_NS_DEV_PM_OPS EXPORT_NS_GPL_DEV_PM_OPS and potentially the non namespaced versions. Thanks, Jonathan