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 3AA96C43334 for ; Tue, 12 Jul 2022 15:23:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233671AbiGLPXK (ORCPT ); Tue, 12 Jul 2022 11:23:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54500 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233183AbiGLPWq (ORCPT ); Tue, 12 Jul 2022 11:22:46 -0400 Received: from mail-io1-f42.google.com (mail-io1-f42.google.com [209.85.166.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 948A4C1761; Tue, 12 Jul 2022 08:21:34 -0700 (PDT) Received: by mail-io1-f42.google.com with SMTP id h200so8117280iof.9; Tue, 12 Jul 2022 08:21:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=dDdtW6rNYIAp97Z79cLxZ45hBOzgYdm8qs6dwMe06kE=; b=udXhXjgi2WEeMemHhvb5hdhOGX3OIAtuCq1xW9wadYLW0gst3vybHdwF2jgRF4pYNv SbJOLjf+naRZhPgXPtt1IH+5e2rdKXrkcSQa5YsHbGm3wC/tH0gG6YanjlWksRZ2MWG0 hW1wBjondEaoVCVZ3Qk2hwmivJ9lJsX4ZvrCiPM+V8wjngIOSq+1TAJWt3wb3M/DKjIc sAGc6qZmpnEiey0vOiKQUuaRZyXYnLBgV/rHNl1yDxw+YQ0YPvvXjqQSxZFKdXAWaYCX H4x4bholJ/OIcgjMqQp3fDVJQW+x2l/CmVaR5gt2h4DpytBWSV5csN54KIh09IPv+f1+ uwUA== X-Gm-Message-State: AJIora92EYhDyEyP3MEl9oN+sqZvnUqDP+DJS3KEWfLQSJGNWxJOrPx5 9Og2BaxthyoKcM+4saQJ6g== X-Google-Smtp-Source: AGRyM1u4Wa6kjd1im1mCu+hIdmoX1OrX7mux3KsADPgZgjKXuPCus7u6YBCHY1jBifOYL9R8YJ2wCg== X-Received: by 2002:a05:6638:4126:b0:33f:6bc0:f8e7 with SMTP id ay38-20020a056638412600b0033f6bc0f8e7mr3449861jab.189.1657639293815; Tue, 12 Jul 2022 08:21:33 -0700 (PDT) Received: from robh.at.kernel.org ([64.188.179.248]) by smtp.gmail.com with ESMTPSA id m21-20020a02a155000000b00339e2f0a9bfsm4228957jah.13.2022.07.12.08.21.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 12 Jul 2022 08:21:33 -0700 (PDT) Received: (nullmailer pid 1879877 invoked by uid 1000); Tue, 12 Jul 2022 15:21:31 -0000 Date: Tue, 12 Jul 2022 09:21:31 -0600 From: Rob Herring To: Martin Blumenstingl Cc: linux-phy@lists.infradead.org, devicetree@vger.kernel.org, p.zabel@pengutronix.de, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, vkoul@kernel.org, kishon@ti.com, rtanwar@maxlinear.com Subject: Re: [PATCH v1 3/9] dt-bindings: reset: intel,rcu-gw: Update bindings for "legacy" SoCs Message-ID: <20220712152131.GC1823936-robh@kernel.org> References: <20220628124441.2385023-1-martin.blumenstingl@googlemail.com> <20220628124441.2385023-4-martin.blumenstingl@googlemail.com> <20220701163350.GA1078312-robh@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 03, 2022 at 01:04:20AM +0200, Martin Blumenstingl wrote: > Hi Rob, > > On Fri, Jul 1, 2022 at 6:33 PM Rob Herring wrote: > > > > On Tue, Jun 28, 2022 at 02:44:35PM +0200, Martin Blumenstingl wrote: > > > The Lantiq Amazon-SE, Danube, xRX100 and xRX200 SoCs have up to two USB2 > > > PHYs which are part of the RCU register space. The RCU registers on > > > these SoCs are using big endian. Update the binding for these SoCs to > > > properly describe this IP: > > > - Add compatible strings for Amazon-SE, Danube and xRX100 > > > - Rename the xRX200 compatible string (which is not used anywhere) and > > > switch to the one previously documented in mips/lantiq/rcu.txt > > > - Allow usage of "simple-mfd" and "syscon" in the compatible string so the > > > child devices (USB2 PHYs) can be described > > > - Allow #address-cells and #size-cells to be set to 1 for describing the > > > child devices (USB2 PHYs) > > > - #reset-cells must always be 3 (offset, reset bit and status bit) on the > > > legacy SoCs while LGM uses a fixed value of 2 (offset and reset bit - > > > status bit is always identical to the reset bit). > > > > > > Signed-off-by: Martin Blumenstingl > > > --- > > > .../bindings/reset/intel,rcu-gw.yaml | 84 +++++++++++++++++-- > > > 1 file changed, 79 insertions(+), 5 deletions(-) > > > > > > diff --git a/Documentation/devicetree/bindings/reset/intel,rcu-gw.yaml b/Documentation/devicetree/bindings/reset/intel,rcu-gw.yaml > > > index be64f8597710..b90913c7b7d3 100644 > > > --- a/Documentation/devicetree/bindings/reset/intel,rcu-gw.yaml > > > +++ b/Documentation/devicetree/bindings/reset/intel,rcu-gw.yaml > > > @@ -11,9 +11,16 @@ maintainers: > > > > > > properties: > > > compatible: > > > - enum: > > > - - intel,rcu-lgm > > > - - intel,rcu-xrx200 > > > > It is okay to remove/change this because ? > I'll update the description in v2. The "intel,rcu-xrx200" compatible > string isn't used anywhere (upstream or downstream in OpenWrt). > u-boot on Lantiq xRX200 SoCs is too old to pass a dtb to the kernel, > so we're appending the DTB to the kernel image. > > > > + oneOf: > > > + - items: > > > + - enum: > > > + - lantiq,ase-rcu > > > + - lantiq,danube-rcu > > > + - lantiq,xrx100-rcu > > > + - lantiq,xrx200-rcu > > > + - const: simple-mfd > > > > This says child nodes have 0 dependence on anything in the parent node. > > Such as a clock in the parent needing to be enabled. > > > > > + - const: syscon > > > > Given the child nodes depend on this, I find the combination to be a > > contradiction. But it's widely used, so oh well. > I can think of two ways to solve this: > 1) remove the simple-mfd compatible string and make the driver also > discover child nodes > 2) remove the simple-mfd compatible string and remove the USB PHY > child nodes - then add add #phy-cells = <1> to the RCU node itself > (and somehow update the RCU and USB PHY drivers accordingly) > 3) introduce a separate child node for the reset-controller, then the > child nodes depend on each other (but there's no strict dependency on > the parent anymore other than the fact that the parent needs a > "syscon" compatible string). > > My understanding of this IP block is that it was initially designed as > a reset controller, hence its name "reset controller unit" (RCU). Then > additional logic was added after the fact. > So I think 1) (dropping the simple-mfd compatible string) or 2) > (dropping the simple-mfd compatible string and the child nodes > altogether) is the right way to go here. Which route would you go and > why? 2 would be my choice. That's the simplest binding. Unless the phy registers show up in different places on multiple devices, then maybe it's worth keeping the child node. Rob