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=-4.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 0EC99C433DB for ; Tue, 9 Feb 2021 22:31:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D26E964DD8 for ; Tue, 9 Feb 2021 22:31:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233500AbhBIWab (ORCPT ); Tue, 9 Feb 2021 17:30:31 -0500 Received: from mail-ua1-f42.google.com ([209.85.222.42]:38331 "EHLO mail-ua1-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233956AbhBIWU1 (ORCPT ); Tue, 9 Feb 2021 17:20:27 -0500 Received: by mail-ua1-f42.google.com with SMTP id y35so987336uad.5; Tue, 09 Feb 2021 14:18:57 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=chF4AGWod1NaZkKppPWEQ1Io26jYw+8zMgU0N2aN71E=; b=Rd/iXNwp/bRwoAvDkfjCUAvVcziQWVONRtksXMfYCcBp/fbMKt03L2b2d6EqxKNgph g78S3ST5+36vPwRxpukhyEud/98HB7xiQvXl3Zy81wdYwhuvipLCwIxkxZTyNj+ceanG saImCa+6fsFDKt6wq/7NwJOualvXq3No7nD0LbYkgVDuMRkfQpC9iV5o+wMhF3Ur+ct1 GAtAEYFpN7RKpa45karFIbZbmrDYWICbpgTvNXUfm7wZULl93Zfn0yUndcjol8VCAg58 +xHisVzJW/JWP9epmdrVkbDXwDWpQIyPbrbp0tYGeIhRvrpUT1d8KEazrniTrFcRJ16+ XPpw== X-Gm-Message-State: AOAM5305dyPaOUzMIBhVvEM3TUozW2j41Q5jqGh6ImxfO01wr5nlw0dH R/M5LYL0lixXwO7cJHLpH1u5fkkdYw== X-Google-Smtp-Source: ABdhPJyGu3u5I/yz8BcR5c4Z5Un368IPwJTe9EIJ9SQLRz14qAclf658hUeQwMCs2kjkfjj8BHycEw== X-Received: by 2002:a9d:21ca:: with SMTP id s68mr17271906otb.164.1612906403390; Tue, 09 Feb 2021 13:33:23 -0800 (PST) Received: from robh.at.kernel.org (24-155-109-49.dyn.grandenetworks.net. [24.155.109.49]) by smtp.gmail.com with ESMTPSA id o83sm418383ooo.37.2021.02.09.13.33.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 09 Feb 2021 13:33:22 -0800 (PST) Received: (nullmailer pid 232145 invoked by uid 1000); Tue, 09 Feb 2021 21:33:20 -0000 Date: Tue, 9 Feb 2021 15:33:20 -0600 From: Rob Herring To: Saravana Kannan Cc: Jonathan Corbet , Greg Kroah-Hartman , "Rafael J. Wysocki" , Kevin Hilman , Ulf Hansson , Len Brown , Len Brown , Pavel Machek , Michael Turquette , Stephen Boyd , Frank Rowand , Marc Zyngier , Thomas Gleixner , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org, linux-acpi@vger.kernel.org, Marek Szyprowski , Geert Uytterhoeven , kernel-team@android.com Subject: Re: [PATCH v4 4/8] of: property: Add fw_devlink support for optional properties Message-ID: <20210209213320.GA219007@robh.at.kernel.org> References: <20210205222644.2357303-1-saravanak@google.com> <20210205222644.2357303-5-saravanak@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210205222644.2357303-5-saravanak@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org On Fri, Feb 05, 2021 at 02:26:40PM -0800, Saravana Kannan wrote: > Not all DT bindings are mandatory bindings. Add support for optional DT > bindings and mark iommus, iommu-map, dmas as optional DT bindings. I don't think we can say these are optional or not. It's got to be a driver decision somehow. For example, if IOMMU is optional, what happens with this sequence: driver probes without IOMMU driver calls dma_map_?() IOMMU driver probes h/w accesses DMA buffer --> BOOM!