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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 998BDFA3740 for ; Mon, 31 Oct 2022 08:59:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Subject:From:References:Cc: To:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=obrDzg5WW6lmNH3XjEg537NxUc3q3SJTZ/OZUWOHgaA=; b=hhQEftFeqAlXDd kzsEK5VsIuDb/CsPfvPc7B3sM+wY09tUwJC3vkDNd//CdrGx/NBNDF07Jr7ktz1T8G3JJAdpYKlE8 D0MGbWj2byaacwcsxPfFvNSgv9HjD1X6N/l59Yv8IXedMtJYO92D88L44U7I4PO5ouUOqL0eyErRe ITyw8xQv0C+21XHk65uQdjgefeos2eQ2zE1sA4UPQ6p+bpSa7Xf8uPuC8qh74qCkWjqnuYxs7XGXB cw/Ga58pdNyfVILZuqUcEvGi+HC567p8+JgH8zmQkZe5HTg4aXXdTp20uzE/872H1cfz0FDHz+Nm5 ZdDTrMQwcqNsV1L8ppzw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1opQcm-009mQD-AK; Mon, 31 Oct 2022 08:58:28 +0000 Received: from marcansoft.com ([212.63.210.85] helo=mail.marcansoft.com) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1opQci-009mNK-IP for linux-arm-kernel@lists.infradead.org; Mon, 31 Oct 2022 08:58:26 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: marcan@marcan.st) by mail.marcansoft.com (Postfix) with ESMTPSA id E0C6241A42; Mon, 31 Oct 2022 08:58:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=marcan.st; s=default; t=1667206690; bh=OTa1+8o7mYyJcDcaIQoNw1DovJ5wxNno2mZ54SxYZDQ=; h=Date:To:Cc:References:From:Subject:In-Reply-To; b=gWkgUAD2ESePZcKbNTSwjn82lNH0L9FCOUk7gOeeLEm6gZ4JTgNeoA11/bNf3VUSe RKve+W/ENMXLrPb/cTh42z3zRHm44WWAq6oywgfZflexJ9qwFre26Mppc/7WEfNNvk LdrkpaQKPPHcVX5TsXIBXZVlC/xP0ndhJDgxAnIKPmB7Qm55uIzUabPOdfBnEEv+no U3VSa2Gp8+zUx2BUvosHpADmSRQFcbFlt2DPrivSoulSeyEPN/NrO+BamcOmfVtZvs 8XDhhSBOqHBJW4adPsLUZssMMJQDIan4EZnP+iI4x4oU53opAukw2z4LasFVtlc8c1 Ll+TX/rdiI4yw== Message-ID: Date: Mon, 31 Oct 2022 17:58:05 +0900 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Content-Language: en-US To: Lee Jones Cc: Russell King , Arnd Bergmann , Linus Walleij , Alyssa Rosenzweig , asahi@lists.linux.dev, Bartosz Golaszewski , linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, Sven Peter References: <45ed0a37-60ac-3a06-92d1-6b30e18261ff@marcan.st> <8f30a490-f970-6605-20cb-c2256daab9de@marcan.st> <82088b05-2a0d-69cc-ba2c-d61c74c9d855@marcan.st> From: Hector Martin Subject: Re: [PATCH 4/6] platform/apple: Add new Apple Mac SMC driver In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221031_015825_345498_90081AEA X-CRM114-Status: GOOD ( 20.67 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 31/10/2022 17.48, Lee Jones wrote: > On Sat, 29 Oct 2022, Hector Martin wrote: > >> On 09/09/2022 16.50, Lee Jones wrote: >>>> What's the point of just having effectively an array of mfd_cell and >>>> wrappers to call into the mfd core in the drivers/mfd/ tree and the >>>> rest of the driver elsewhere? >>> >>> They should be separate drivers, with MFD registering the Platform. >> >> Why? What purpose does this serve? I'm still confused. There's one >> parent device, which provides services to the child devices. There isn't >> one parent device which wraps a platform service which is used by >> children. This makes no sense. The platform device is the root, if it >> exposes MFD services, then it has to be in that direction, not the other >> way around. >> >> Look at how this patch series is architected. There is smc_core.c, which >> implements SMC helpers and wrappers on top of a generic backend, and >> registers with the MFD subsystem. And then there is smc_rtkit.c which is >> the actual platform implementation on top of the RTKit framework, and is >> the actual platform device entry point. >> >> A priori, the only thing that makes sense to me right now would be to >> move smc_core.c into drivers/mfd, and leave smc_rtkit.c in platform. >> That way the mfd registration would be in drivers/mfd (as would be the >> services offered to sub-drivers), but the actual backend implementation >> would be in platform/ (and there would eventually be others, e.g. at >> least two more for x86 systems). That does mean that the driver entry >> point will be in platform/, with mfd/smc_core.c serving as effectively >> library code to plumb in the mfd stuff into one of several possible >> platform devices. Would that work for you? > > Yes, sounds sensible. However, keep all of the abstraction craziness > somewhere else and fetch and share all of your shared resources from > the MFD (SMC) driver. I'm not sure what you mean by that. The abstraction (smc_core.c) *is* the shared resource. All it does is wrap ops callbacks with a mutex and add a couple helpers for finding keys. Do you literally want us to just have this in drivers/mfd? // SPDX-License-Identifier: GPL-2.0-only OR MIT /* * Apple SMC MFD wrapper * Copyright The Asahi Linux Contributors */ #include #include "smc.h" static const struct mfd_cell apple_smc_devs[] = { { .name = "macsmc-gpio", }, { .name = "macsmc-hid", }, { .name = "macsmc-power", }, { .name = "macsmc-reboot", }, { .name = "macsmc-rtc", }, }; int apple_smc_add_mfd_devices(struct device *dev) { ret = mfd_add_devices(dev, -1, apple_smc_devs, ARRAY_SIZE(apple_smc_devs), NULL, 0, NULL); if (ret) return dev_err_probe(dev, ret, "Subdevice initialization failed"); return 0; } EXPORT_SYMBOL(apple_smc_add_mfd_devices); int apple_smc_remove_mfd_devices(struct device *dev) { mfd_remove_devices(smc->dev); return 0; } EXPORT_SYMBOL(apple_smc_add_mfd_devices); MODULE_AUTHOR("Hector Martin "); MODULE_LICENSE("Dual MIT/GPL"); MODULE_DESCRIPTION("Apple SMC MFD wrapper"); Because this feels *immensely* silly and pointless. - Hector _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel