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 CE625C433F5 for ; Wed, 23 Mar 2022 15:07:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245024AbiCWPJK convert rfc822-to-8bit (ORCPT ); Wed, 23 Mar 2022 11:09:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244993AbiCWPJF (ORCPT ); Wed, 23 Mar 2022 11:09:05 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AB9407D03D for ; Wed, 23 Mar 2022 08:07:35 -0700 (PDT) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1nX2a8-0004Yt-FC; Wed, 23 Mar 2022 16:07:28 +0100 Received: from [2a0a:edc0:0:900:1d::4e] (helo=lupine) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.94.2) (envelope-from ) id 1nX2a4-002Vih-QY; Wed, 23 Mar 2022 16:07:27 +0100 Received: from pza by lupine with local (Exim 4.94.2) (envelope-from ) id 1nX2a6-0007nK-BN; Wed, 23 Mar 2022 16:07:26 +0100 Message-ID: Subject: Re: [PATCH 0/2] add fwnode support to reset subsystem From: Philipp Zabel To: =?ISO-8859-1?Q?Cl=E9ment_L=E9ger?= , Rob Herring , Frank Rowand Cc: Thomas Petazzoni , Alexandre Belloni , Allan Nielsen , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Date: Wed, 23 Mar 2022 16:07:26 +0100 In-Reply-To: <20220323095022.453708-1-clement.leger@bootlin.com> References: <20220323095022.453708-1-clement.leger@bootlin.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT User-Agent: Evolution 3.38.3-1 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: p.zabel@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Clément, On Mi, 2022-03-23 at 10:50 +0100, Clément Léger wrote: > This series is part of a larger series which aims at adding fwnode > support in multiple subsystems [1]. The goal of this series was to > add support for software node in various subsystem but in a first > time only the fwnode support had gained consensus and will be added > to multiple subsystems. Could you explain the purpose of this a little? From the referenced mail it looks like this would be intended allow to register reset controllers via software node? Are there any real systems where this would be useful? > For the moment ACPI node support is excluded from the fwnode support > to avoid creating an unspecified ACPI reset device description. Are there any plans or ongoing discussions to specify such a description in the future? Right now I'm only aware of the ACPI _RST method as used by this patch: [1] https://lore.kernel.org/all/20220307135626.16673-1-kyarlagadda@nvidia.com/ > One question raised by this series is that I'm not sure if all reset > drivers should be modified to use the new fwnode support or keep the > existing device-tree support. Maintainer advice on that particular > question will be welcome. I would prefer not to have to switch all those small DT-only reset controller drivers all over the tree from of_node to fwnode. On the other hand, I think it would be good to avoid the direct of_node assignment, possibly by letting devm_reset_controller_register() initialize of_node or fwnode from the device for most cases, and by adding of_reset_controller_register() and fwnode_reset_controller_register() variants that take the node as an argument for the rest. That could allow to eventually get rid of the of_node pointer. For those drivers that provide their own .of_xlate, I'm not sure it would make sense to force them to use .fwnode_xlate if they don't already have a reason to use fwnode on their own. regards Philipp