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 5FD4AECAAD5 for ; Tue, 6 Sep 2022 17:41:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230087AbiIFRlJ (ORCPT ); Tue, 6 Sep 2022 13:41:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230173AbiIFRkv (ORCPT ); Tue, 6 Sep 2022 13:40:51 -0400 Received: from out5-smtp.messagingengine.com (out5-smtp.messagingengine.com [66.111.4.29]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 09D2EDF7; Tue, 6 Sep 2022 10:40:49 -0700 (PDT) Received: from compute2.internal (compute2.nyi.internal [10.202.2.46]) by mailout.nyi.internal (Postfix) with ESMTP id A39CA5C0112; Tue, 6 Sep 2022 13:40:46 -0400 (EDT) Received: from imap47 ([10.202.2.97]) by compute2.internal (MEProxy); Tue, 06 Sep 2022 13:40:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=svenpeter.dev; h=cc:cc:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:sender :subject:subject:to:to; s=fm2; t=1662486046; x=1662572446; bh=Il uLvD7LxFvPGQxaEMXS0bap3YchZZokW0Mbe2PU1WI=; b=zSGj2qrA1ca9iUo7QK rUcC38XExyPDBiK9wdOsl14C+tCugUGTdvjb/bzdLcF0ApKMCIjgLUDZ/Cs3ubHt X0MIIVkybjyy8ncJawu9NTI22hTnFHK7kqf406d92PT5GstyZMOlWjQXt8CdC46p +X19DLlbFBQk8IbvGa+7tbxEAAkEwOCWMsaeycgj4SWXVRtFdLegTIOKOX/NiM3j v6a5R8r2uUCn0R1v2kHa0lUNCxBvc1h5EgRf/uypfSjYgaFoqCPKwpETGgFHluSb /WGT5bqtIWWxcJXE1SqdYCHtST4Dfk8I/WkpNjARkg3oIVj8Uc1f/z2aepyjf1Zq 9XWg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:date:date:feedback-id :feedback-id:from:from:in-reply-to:in-reply-to:message-id :mime-version:references:reply-to:sender:subject:subject:to:to :x-me-proxy:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s= fm2; t=1662486046; x=1662572446; bh=IluLvD7LxFvPGQxaEMXS0bap3Ych ZZokW0Mbe2PU1WI=; b=GYzhCe6gD/BzcKwcws2jmcdWHw4mpu+7dWTqvsT+5pk4 T91m7mWbE/8yrPDOXpKOgT3bYRBE7fGsU184w80f2TDoLHpvZTnKxKdzgpyuPrt4 svLWEuJxVm8mu66Q5FN2cVOHkVqD2OQNIQFVIHxqJbZBnjdhtVMYjGZY9k2HE734 xAHKWYBTSNd21I6mdJHKPXW58QitpKEpNDC7moDFY/QLrrAnBa32f6so6HzIqAMA tTFTSHqItrYzSNB9MPl22snipdrnJXNO13U+vCkKblL6h/yqvxVSZESTa+WBqogs iMhYE+FH0SunwwwL7UMjN2cCuw83FHiY48mR3nQsUg== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvfedrvdelkedgudduiecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enucfjughrpefofgggkfgjfhffhffvvefutgesthdtredtreertdenucfhrhhomhepfdfu vhgvnhcurfgvthgvrhdfuceoshhvvghnsehsvhgvnhhpvghtvghrrdguvghvqeenucggtf frrghtthgvrhhnpeelvefggeffheevtdeivefhkeehfeettdejteduveeiheevveeilefg hfeiveeiueenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhroh hmpehsvhgvnhesshhvvghnphgvthgvrhdruggvvh X-ME-Proxy: Feedback-ID: i51094778:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id A76CEA6007C; Tue, 6 Sep 2022 13:40:45 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.7.0-alpha0-927-gf4c98c8499-fm-20220826.002-gf4c98c84 Mime-Version: 1.0 Message-Id: <0cbfd45e-4749-424e-8c28-362d9b4f435e@www.fastmail.com> In-Reply-To: <20220906173535.GA734389-robh@kernel.org> References: <2fedff34-6a20-f1ce-a756-2bd8671fcd52@linaro.org> <20220902172808.GB52527-robh@kernel.org> <20220906161049.GC534217-robh@kernel.org> <91466e41-d3f7-0993-9082-80f94e53f375@marcan.st> <20220906173535.GA734389-robh@kernel.org> Date: Tue, 06 Sep 2022 19:40:18 +0200 From: "Sven Peter" To: "Rob Herring" , "Hector Martin" Cc: "Russell King (Oracle)" , "Mark Kettenis" , krzysztof.kozlowski@linaro.org, "Arnd Bergmann" , "Lee Jones" , "Linus Walleij" , "Alyssa Rosenzweig" , asahi@lists.linux.dev, "Bartosz Golaszewski" , linux-arm-kernel@lists.infradead.org, "open list:GPIO SUBSYSTEM" , "Krzysztof Kozlowski" , devicetree@vger.kernel.org Subject: Re: [PATCH 1/6] dt-bindings: mfd: add binding for Apple Mac System Management Controller Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Tue, Sep 6, 2022, at 19:35, Rob Herring wrote: > On Wed, Sep 07, 2022 at 02:00:53AM +0900, Hector Martin wrote: >> On 07/09/2022 01.10, Rob Herring wrote: >> >> So at this point, I think it would make sense if I post a v2 with all >> >> the updates so far (sorry, given the long drawn out discussions on >> >> this, I've lost track of what changes have been made to the code, so >> >> I won't include a detailed change log.) >> > >> > As I said elsewhere, sub-nodes is probably the right choice here. I >> > think they need compatible strings in the child nodes, and addressing >> > has to be sorted out which it seems may also break OpenBSD. >> >> So addressing only makes sense for GPIO, out of the nodes we have so far >> - that's the only thing with two discrete instances whose access can be >> entirely described by a single base key name, and which are otherwise >> compatible. >> >> Everything else is pretty much single-instance, and talks to multiple >> keys, so there isn't one single "address" key that would make semantic >> sense to use as the node address. > > Unit-addresses are just the first address in 'reg'. So multiple > addresses or not doesn't really matter. > >> There are some indexed keys, but at a >> deeper level (e.g. multiple battery cells part of the charge control >> subsystem, multiple Type C ports as part of the AC/power input >> subsystem, etc.). And in those cases, these subdevices are mostly >> homogeneous and we would never need multiple nodes for them at the DT >> level, they'd just be implicitly handled by those drivers. > > Type-C will be fun depending on how much of the muxing/altmode > details have to get exposed. Type-C is going to be a lot of "fun", but the SMC is not directly involved. I still don't have a full picture but these boards have TPS6598x chips which trigger the entire mess whenever a new mode was negotiated and the "Apple Type-C PHY" contains the actual mux. The SMC has a side channel to these TPS6598x chips as well but it seems to only handle charging without having to communicate with whatever kernel is running on the main processor. Sven