From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oa1-f48.google.com (mail-oa1-f48.google.com [209.85.160.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 631498479 for ; Mon, 23 Jan 2023 17:53:41 +0000 (UTC) Received: by mail-oa1-f48.google.com with SMTP id 586e51a60fabf-15fe106c7c7so8724878fac.8 for ; Mon, 23 Jan 2023 09:53:41 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=HezRXXIQxXPtMIWpEGs9XWajQCD0kCzEdwMP0szra1Y=; b=GcLxbIIzO33pNI/kEP568g1PrbewlfsvnMU6HzP4q47rWpjuiWPM/IKNNPpnPo+CWC P4cNQ8LFUxM8NMuxf0NLVUZGkeKlD80I4Lv5DfNsYfVd5qCIrXFlH3+WcciDh+wnIMMn 37eYmBnKkQCplH/qM7nwZ8HDSzgSRXxuvamC1lLfNi0DTH41v72n6ZAiwWbjtTNAP2Xh jhVO6U+BC+d6J0phk9q9nr/qfQrq3RN+3/jtDAfbQrxafkXIJ6IqvXHxSPHVnCWS1Qzl xlOHFuMB5u8jm0plJjLxLB+Vw5/Q8oDkojg6pVG9iPQb2jKjG6Q9MlFPNyWqSfVnQ0kL MjkA== X-Gm-Message-State: AFqh2kqakIAfXvWeQDgMznu6TuPAbmYnid463dY2PxaLTKfzG533pxEi ngz67sjVg1zvFR5+TSXyvQ== X-Google-Smtp-Source: AMrXdXsdPNG8TH0x+2IAyk2abcc9M+PaIG7GDMdhZabCSwFyK7idZOfBF+6vwpZb+UKigpv5r9mK7g== X-Received: by 2002:a05:6870:494b:b0:143:e045:7082 with SMTP id fl11-20020a056870494b00b00143e0457082mr12913559oab.58.1674496420250; Mon, 23 Jan 2023 09:53:40 -0800 (PST) Received: from robh_at_kernel.org (66-90-144-107.dyn.grandenetworks.net. [66.90.144.107]) by smtp.gmail.com with ESMTPSA id bd36-20020a056808222400b00364ebf27363sm15742oib.0.2023.01.23.09.53.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Jan 2023 09:53:39 -0800 (PST) Received: (nullmailer pid 2113958 invoked by uid 1000); Mon, 23 Jan 2023 17:53:39 -0000 Date: Mon, 23 Jan 2023 11:53:39 -0600 From: Rob Herring To: Rayyan Ansari Cc: dri-devel@lists.freedesktop.org, ~postmarketos/upstreaming@lists.sr.ht, asahi@lists.linux.dev, janne@jannau.net, Daniel Vetter , David Airlie , devicetree@vger.kernel.org, Hans de Goede , Javier Martinez Canillas , Krzysztof Kozlowski , linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Thomas Zimmermann Subject: Re: [PATCH v2 2/2] dt-bindings: display: simple-framebuffer: Document physical width and height properties Message-ID: <20230123175339.GA2019900-robh@kernel.org> References: <20230121153544.467126-1-rayyan@ansari.sh> <20230121153544.467126-3-rayyan@ansari.sh> Precedence: bulk X-Mailing-List: asahi@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Sun, Jan 22, 2023 at 05:25:38PM +0000, Rayyan Ansari wrote: > On 22/01/2023 15:36, Rob Herring wrote: > > On Sat, Jan 21, 2023 at 9:36 AM Rayyan Ansari wrote: > > > > > > > Why do you need this change? > > > > The 'simple-framebuffer' contains data on how the bootloader > > configured the display. The bootloader doesn't configure the display > > size, so this information doesn't belong here. The information should > > already be in the panel node, so also no point in duplicating it here. > > > > > Signed-off-by: Rayyan Ansari > > > --- > > > .../devicetree/bindings/display/simple-framebuffer.yaml | 8 ++++++++ > > > 1 file changed, 8 insertions(+) > > Hi Rob, > > There is the usecase that Hans has mentioned, but I have also mentioned > another usecase previously. > > Adding the width-mm and height-mm properties allows user interfaces such as > Phosh (https://puri.sm/posts/phosh-overview/) to scale correctly to the > screen. In my case, a panel node is not available and the aforementioned > interface is in fact running on the SimpleDRM driver (which binds to the > simple-framebuffer device). Why is the panel node not available? Why not add it? Presumably it is not there because you aren't (yet) using the simple-panel driver (and others that would need). But presumably you will eventually as I'd imagine turning the screen off and back on might be a desired feature. So why add a temporary DT property that's tied to your *current* kernel? The DT should not be tightly coupled to the kernel. Rob 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 CF504C25B50 for ; Mon, 23 Jan 2023 17:53:44 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CE6AE10E51E; Mon, 23 Jan 2023 17:53:43 +0000 (UTC) Received: from mail-oa1-f43.google.com (mail-oa1-f43.google.com [209.85.160.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7516B10E51E for ; Mon, 23 Jan 2023 17:53:41 +0000 (UTC) Received: by mail-oa1-f43.google.com with SMTP id 586e51a60fabf-15f83e0fc63so14803625fac.11 for ; Mon, 23 Jan 2023 09:53:41 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=HezRXXIQxXPtMIWpEGs9XWajQCD0kCzEdwMP0szra1Y=; b=MNSM1rgMzzUl1NFT/9O4KvO6c5plmzhuRz1FCEzEfS3vqBAJwIkfGCqeiGGdeOLJzd qoZXiL0qFBYN9ShmLvOYiiBzd5wMyub2xsZqgto11JmG4ScJsIUmNBBFTQDlL0kbn6+q Cu0g5CJmDhN0SG/ank4Y9s5cIMP9kx14l8XYQBZNwQz6txjXbSFHD7/dPAtKR/wtaykb z9arr0jzoXpg/FzRxm1PX+MvgqrYsAhX4NSl/QHEomjlG7O1ZDoC4/3Y91lb33wzs/n8 oolZUQPGAlsZXyg9ESs7YB4x8J/KemuI2bG1sVVwHy+g/ybxoMjSl5fC84JWVsN87k1h tb/w== X-Gm-Message-State: AFqh2krUdks6wg1Qc1rppFTzqTFP//JN504PM+quxdRjTbOT2BEoaxPn ddhYMWWgvbMh3lca/1EqAg== X-Google-Smtp-Source: AMrXdXsdPNG8TH0x+2IAyk2abcc9M+PaIG7GDMdhZabCSwFyK7idZOfBF+6vwpZb+UKigpv5r9mK7g== X-Received: by 2002:a05:6870:494b:b0:143:e045:7082 with SMTP id fl11-20020a056870494b00b00143e0457082mr12913559oab.58.1674496420250; Mon, 23 Jan 2023 09:53:40 -0800 (PST) Received: from robh_at_kernel.org (66-90-144-107.dyn.grandenetworks.net. [66.90.144.107]) by smtp.gmail.com with ESMTPSA id bd36-20020a056808222400b00364ebf27363sm15742oib.0.2023.01.23.09.53.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Jan 2023 09:53:39 -0800 (PST) Received: (nullmailer pid 2113958 invoked by uid 1000); Mon, 23 Jan 2023 17:53:39 -0000 Date: Mon, 23 Jan 2023 11:53:39 -0600 From: Rob Herring To: Rayyan Ansari Subject: Re: [PATCH v2 2/2] dt-bindings: display: simple-framebuffer: Document physical width and height properties Message-ID: <20230123175339.GA2019900-robh@kernel.org> References: <20230121153544.467126-1-rayyan@ansari.sh> <20230121153544.467126-3-rayyan@ansari.sh> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, linux-fbdev@vger.kernel.org, janne@jannau.net, Krzysztof Kozlowski , Thomas Zimmermann , Javier Martinez Canillas , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Hans de Goede , ~postmarketos/upstreaming@lists.sr.ht, asahi@lists.linux.dev Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Sun, Jan 22, 2023 at 05:25:38PM +0000, Rayyan Ansari wrote: > On 22/01/2023 15:36, Rob Herring wrote: > > On Sat, Jan 21, 2023 at 9:36 AM Rayyan Ansari wrote: > > > > > > > Why do you need this change? > > > > The 'simple-framebuffer' contains data on how the bootloader > > configured the display. The bootloader doesn't configure the display > > size, so this information doesn't belong here. The information should > > already be in the panel node, so also no point in duplicating it here. > > > > > Signed-off-by: Rayyan Ansari > > > --- > > > .../devicetree/bindings/display/simple-framebuffer.yaml | 8 ++++++++ > > > 1 file changed, 8 insertions(+) > > Hi Rob, > > There is the usecase that Hans has mentioned, but I have also mentioned > another usecase previously. > > Adding the width-mm and height-mm properties allows user interfaces such as > Phosh (https://puri.sm/posts/phosh-overview/) to scale correctly to the > screen. In my case, a panel node is not available and the aforementioned > interface is in fact running on the SimpleDRM driver (which binds to the > simple-framebuffer device). Why is the panel node not available? Why not add it? Presumably it is not there because you aren't (yet) using the simple-panel driver (and others that would need). But presumably you will eventually as I'd imagine turning the screen off and back on might be a desired feature. So why add a temporary DT property that's tied to your *current* kernel? The DT should not be tightly coupled to the kernel. Rob