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=-6.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 0EDEBC4338F for ; Mon, 2 Aug 2021 20:32:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E086D61102 for ; Mon, 2 Aug 2021 20:32:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231434AbhHBUch (ORCPT ); Mon, 2 Aug 2021 16:32:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:56182 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230448AbhHBUcg (ORCPT ); Mon, 2 Aug 2021 16:32:36 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2325360F93; Mon, 2 Aug 2021 20:32:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627936346; bh=RjKhF4hB/2KcuyIWUfAzYtZZ8R9Gf1asDHL4YKxZRlk=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=XoKTKyFs/895DJ6gXNmOgln+KqAa1z/0hs5DJFFQCBLqrUB564mpKLe6QnoO5cP9j wxRdd4t9mU89DkAij4LuWxqWQDtN/neVRA4rHZLlrjwb6JBunIp0V+HOFOLKUtlGpQ s34cVHvM020folN28dy0+Twb4aP68R0ri4L7UYw1CGgMjIf/6cTwKLJu/xBV9csgC1 DtKKBTE/EWHmPw1tbLdI84zn5VzRc261nA6egX6EYiLIMBbVQvbJUJXzF7lZpPxGD8 NPUOwBOJNSX2q1lHqjin2RYHrl1kOMEGOdPDEhdigZ0kNZDZim5dO8cUpfDSasDaVL QvjmZ9EnV57DA== Received: by mail-wm1-f47.google.com with SMTP id n11so11151866wmd.2; Mon, 02 Aug 2021 13:32:26 -0700 (PDT) X-Gm-Message-State: AOAM532sSqzUHJ6slFAIVFW1KtkwZG4IH6ocOy+YOZgwefTJCVOIXrTz 5ofSlaCllwtbwx4mnj0LTWxc6aqZDputlPgR1W8= X-Google-Smtp-Source: ABdhPJzYGkFqLqspaoCqN00TaY6q2TQGENW8z+Kn/ypsgZ93keijuGyG0Uyz98n3cAQoC3RU3kB3ITgGfxsX8sNbmis= X-Received: by 2002:a7b:ce10:: with SMTP id m16mr626048wmc.75.1627936344707; Mon, 02 Aug 2021 13:32:24 -0700 (PDT) MIME-Version: 1.0 References: <20210802145937.1155571-1-arnd@kernel.org> <20210802164907.GA9832@hoboy.vegasvil.org> In-Reply-To: From: Arnd Bergmann Date: Mon, 2 Aug 2021 22:32:08 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH net-next v2] ethernet/intel: fix PTP_1588_CLOCK dependencies To: "Keller, Jacob E" Cc: Richard Cochran , Nicolas Pitre , "Brandeburg, Jesse" , "Nguyen, Anthony L" , "David S. Miller" , Jakub Kicinski , Arnd Bergmann , Kurt Kanzenbach , "Saleem, Shiraz" , "Ertman, David M" , "intel-wired-lan@lists.osuosl.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 2, 2021 at 9:54 PM Keller, Jacob E wrote: > > So go back to "select"? > > It looks like Arnd proposed in the thread a solution that did a sort of > "please enable this" but still let you disable it. > > An alternative (unfortunately per-driver...) solution was to setup the > drivers so that they gracefully fall back to disabling PTP if the PTP > core support is not reachable.. but that obviously requires that drivers > do the right thing, and at least Intel drivers have not tested this > properly. > > I'm definitely in favor of removing "implies" entirely. The semantics > are unclear, and the fact that it doesn't handle the case of "i'm > builtin, so my implies can't be modules"... > > I don't really like the syntax of the double "depends on A || !A".. I'd > prefer if we had some keyword for this, since it would be more obvious > and not run against the standard logic (A || !A is a tautology!) I think the main reason we don't have a keyword for it is that nobody so far has come up with an English word that expresses what it is supposed to mean. You can do something like it for a particular symbol though, such as config MAY_USE_PTP_1588_CLOCK def_tristate PTP_1588_CLOCK || !PTP_1588_CLOCK config E1000E tristate "Intel(R) PRO/1000 PCI-Express Gigabit Ethernet support" depends on PCI && (!SPARC32 || BROKEN) + depends on MAY_USE_PTP_1588_CLOCK select CRC32 - imply PTP_1588_CLOCK Arnd