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 2473EC636CD for ; Mon, 30 Jan 2023 21:39:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229900AbjA3VjT (ORCPT ); Mon, 30 Jan 2023 16:39:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56122 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231303AbjA3VjN (ORCPT ); Mon, 30 Jan 2023 16:39:13 -0500 Received: from mail-ot1-f41.google.com (mail-ot1-f41.google.com [209.85.210.41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 24354CA26; Mon, 30 Jan 2023 13:39:07 -0800 (PST) Received: by mail-ot1-f41.google.com with SMTP id e21-20020a9d5615000000b006884e5dce99so4939332oti.5; Mon, 30 Jan 2023 13:39:07 -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=JL/Sa/O/0qzbTgqvZA3y8OHGpThnTm0XwAphUFZl/lg=; b=TYz47oQL4XHMgwjXfDr2LkGzQ65Dayvkn+jrIkSUVwCT/SZKjj4f0SYkbpyNJmnkoC aqrL2FbcXpH3h98+WpSC4LWiFGrfz7Ry+SgCw37ZLBScbelL6INFdlke90uQhDxecMHx S0+0SYOI+klpaY80PV4Sx0kjeSF1huI23GjmlGtucpy0pxFjL/8RlfU0OvOEHW8mUGSF /RVR8hm99ff0soLQdGpL5FnnCbE+FQyJ5PooN6Jc0EnypOeBrrAPaYF9+ori68m1Mhs/ tFksTTQ62qsDm1vJplY9ek17m1U62FiMvDF0xwybYMtd3jDTJH+Aa1AbsERLFCPXW69r tHtw== X-Gm-Message-State: AO0yUKXZbtzvjWYu1f0Yfz79GMPMHFV8lB7XMOZn542wjwOpeRLp8bT9 zlYjN3fVCsAJxVCNF0VWdw== X-Google-Smtp-Source: AK7set/uccH7JTyE212LtTiDDrvQkFVU8TeUda5c03Xe15eIlmEojgcuEnr3VivOzcP4k0dxjP7f3g== X-Received: by 2002:a05:6830:2091:b0:686:56c6:34bd with SMTP id y17-20020a056830209100b0068656c634bdmr4701652otq.14.1675114746291; Mon, 30 Jan 2023 13:39:06 -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 w8-20020a9d5388000000b0068bbb73006bsm3642958otg.47.2023.01.30.13.39.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Jan 2023 13:39:05 -0800 (PST) Received: (nullmailer pid 3575008 invoked by uid 1000); Mon, 30 Jan 2023 21:39:04 -0000 Date: Mon, 30 Jan 2023 15:39:04 -0600 From: Rob Herring To: Liu Ying Cc: Krzysztof Kozlowski , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, andrzej.hajda@intel.com, neil.armstrong@linaro.org, robert.foss@linaro.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, airlied@gmail.com, daniel@ffwll.ch, krzysztof.kozlowski+dt@linaro.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com Subject: Re: [PATCH 1/2] dt-bindings: display: bridge: Add NXP i.MX93 parallel display format configuration Message-ID: <20230130213904.GA3569183-robh@kernel.org> References: <20230128034713.1530218-1-victor.liu@nxp.com> <20230128034713.1530218-2-victor.liu@nxp.com> <3c07b9bd-1981-2945-9efe-80afb0195de8@linaro.org> <87d6f54c4695330064eda295e258a0a5c3bc48f8.camel@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87d6f54c4695330064eda295e258a0a5c3bc48f8.camel@nxp.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 30, 2023 at 04:39:05PM +0800, Liu Ying wrote: > On Sun, 2023-01-29 at 12:46 +0100, Krzysztof Kozlowski wrote: > > On 28/01/2023 04:47, Liu Ying wrote: > > > NXP i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register > > > which > > > configures parallel display format by using the > > > "PARALLEL_DISP_FORMAT" > > > field. Add device tree bindings for the display format > > > configuration. > > > > > > Signed-off-by: Liu Ying > > > --- > > > .../display/bridge/nxp,imx93-pdfc.yaml | 78 > > > +++++++++++++++++++ > > > 1 file changed, 78 insertions(+) > > > create mode 100644 > > > Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > > > > diff --git > > > a/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > new file mode 100644 > > > index 000000000000..a84bfb46b01d > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > @@ -0,0 +1,78 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fdisplay%2Fbridge%2Fnxp%2Cimx93-pdfc.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C7fb1b69849974435787008db01ee832c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638105896131701918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=kkX5B45NTsmDKKzxjOiE6MaE4zkMVbMe4ILammVSwMc%3D&reserved=0 > > > +$schema: > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fmeta-schemas%2Fcore.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C7fb1b69849974435787008db01ee832c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638105896131701918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=vIVpdEjIo6H3V8T7iTbDwz4Bmn0d%2BQB4BCJNJ0OzKJw%3D&reserved=0 > > > + > > > +title: NXP i.MX93 Parallel Display Format Configuration > > > + > > > +maintainers: > > > + - Liu Ying > > > + > > > +description: | > > > + The i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register > > > which > > > + configures parallel display format by using the > > > "PARALLEL_DISP_FORMAT" > > > + field. > > > + > > > +properties: > > > + compatible: > > > + const: nxp,imx93-pdfc > > > > > > Based on description, I have doubts this is a separate bridge device. > > Why this is not part of display driver/bindings? > > The relevant display controller in i.MX93 SoC is LCDIF. From hardware > design PoV, the parallel display format configuration logic is not a > part of LCDIF. Instead, it's a part of i.MX93 mediamix blk-ctrl. The > blk-ctrl includes controls for miscellaneous devices with small logics, > like this parallel display format configuration, LVDS Display > Bridge(LDB, see fsl,ldb.yaml) and so on. The below pipeline describes > data flow of a parallel display LCD panel: > > DRAM -> LCDIF -> parallel display format configuration -> LCD panel > > So, the parallel display format configuration appears to be a separate > bridge. > > > > > We do not create usually devices for single registers, because they > > are > > not a devices. Devices are a bit more complex - have some pin > > inputs/outputs, not a register only. Of course there are exception, > > but > > this one does not look like one. > > IMHO, this one is a standalone device although it is controlled by one > single register. It's input pins connect to LCDIF and output pins > connect to i.MX93 SoC's pins/pads. Fair enough. It needs to be defined as part of the mediamix blkctrl schema though. 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 B99BBC636D6 for ; Mon, 30 Jan 2023 21:39:09 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 266A28924F; Mon, 30 Jan 2023 21:39:09 +0000 (UTC) Received: from mail-ot1-f50.google.com (mail-ot1-f50.google.com [209.85.210.50]) by gabe.freedesktop.org (Postfix) with ESMTPS id 244E38924F for ; Mon, 30 Jan 2023 21:39:07 +0000 (UTC) Received: by mail-ot1-f50.google.com with SMTP id cm26-20020a056830651a00b00684e5c0108dso4932293otb.9 for ; Mon, 30 Jan 2023 13:39:07 -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=JL/Sa/O/0qzbTgqvZA3y8OHGpThnTm0XwAphUFZl/lg=; b=7xTuG+10x2YZHhnnwVVFCYiQVth7pQjL1jZCnmm3f0L7I2s9Lxfu925DDoM3M42B0O LZDFl2KmTRdMcFiazR5VPbacGeqMsXUsnljYyfbSNfACSxwVRhzbOcI1/I3NKfFeW8Bn BzxUvQNm2SQYj3ctutTWGRKxFLnLvBIRTUuOiQw7y4x78cfcDtvk+J9hv56j/ymzNmvL ykH+/IygmqdByWOZutImF2oa++f3TksyfajrpboxCq+i1FvALDRNWTO6XdfznyieyQah iCqzg31+bYPRCBgF0P6/jK1C/6dJmMAhsPZM8PG21JqBpOZ4IVMf8OHTIvWfzXKYxJz5 rUWg== X-Gm-Message-State: AO0yUKVEhs5I9JRo7JCY0kz7L5Z05M/Funr6MHyvxbcUaboolrigsans NYwUyCKq687VWko7ELtA0A== X-Google-Smtp-Source: AK7set/uccH7JTyE212LtTiDDrvQkFVU8TeUda5c03Xe15eIlmEojgcuEnr3VivOzcP4k0dxjP7f3g== X-Received: by 2002:a05:6830:2091:b0:686:56c6:34bd with SMTP id y17-20020a056830209100b0068656c634bdmr4701652otq.14.1675114746291; Mon, 30 Jan 2023 13:39:06 -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 w8-20020a9d5388000000b0068bbb73006bsm3642958otg.47.2023.01.30.13.39.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Jan 2023 13:39:05 -0800 (PST) Received: (nullmailer pid 3575008 invoked by uid 1000); Mon, 30 Jan 2023 21:39:04 -0000 Date: Mon, 30 Jan 2023 15:39:04 -0600 From: Rob Herring To: Liu Ying Subject: Re: [PATCH 1/2] dt-bindings: display: bridge: Add NXP i.MX93 parallel display format configuration Message-ID: <20230130213904.GA3569183-robh@kernel.org> References: <20230128034713.1530218-1-victor.liu@nxp.com> <20230128034713.1530218-2-victor.liu@nxp.com> <3c07b9bd-1981-2945-9efe-80afb0195de8@linaro.org> <87d6f54c4695330064eda295e258a0a5c3bc48f8.camel@nxp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87d6f54c4695330064eda295e258a0a5c3bc48f8.camel@nxp.com> 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, jernej.skrabec@gmail.com, krzysztof.kozlowski+dt@linaro.org, neil.armstrong@linaro.org, shawnguo@kernel.org, s.hauer@pengutronix.de, jonas@kwiboo.se, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Krzysztof Kozlowski , robert.foss@linaro.org, andrzej.hajda@intel.com, linux-imx@nxp.com, kernel@pengutronix.de, linux-arm-kernel@lists.infradead.org, Laurent.pinchart@ideasonboard.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Jan 30, 2023 at 04:39:05PM +0800, Liu Ying wrote: > On Sun, 2023-01-29 at 12:46 +0100, Krzysztof Kozlowski wrote: > > On 28/01/2023 04:47, Liu Ying wrote: > > > NXP i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register > > > which > > > configures parallel display format by using the > > > "PARALLEL_DISP_FORMAT" > > > field. Add device tree bindings for the display format > > > configuration. > > > > > > Signed-off-by: Liu Ying > > > --- > > > .../display/bridge/nxp,imx93-pdfc.yaml | 78 > > > +++++++++++++++++++ > > > 1 file changed, 78 insertions(+) > > > create mode 100644 > > > Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > > > > diff --git > > > a/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > new file mode 100644 > > > index 000000000000..a84bfb46b01d > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > @@ -0,0 +1,78 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fdisplay%2Fbridge%2Fnxp%2Cimx93-pdfc.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C7fb1b69849974435787008db01ee832c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638105896131701918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=kkX5B45NTsmDKKzxjOiE6MaE4zkMVbMe4ILammVSwMc%3D&reserved=0 > > > +$schema: > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fmeta-schemas%2Fcore.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C7fb1b69849974435787008db01ee832c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638105896131701918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=vIVpdEjIo6H3V8T7iTbDwz4Bmn0d%2BQB4BCJNJ0OzKJw%3D&reserved=0 > > > + > > > +title: NXP i.MX93 Parallel Display Format Configuration > > > + > > > +maintainers: > > > + - Liu Ying > > > + > > > +description: | > > > + The i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register > > > which > > > + configures parallel display format by using the > > > "PARALLEL_DISP_FORMAT" > > > + field. > > > + > > > +properties: > > > + compatible: > > > + const: nxp,imx93-pdfc > > > > > > Based on description, I have doubts this is a separate bridge device. > > Why this is not part of display driver/bindings? > > The relevant display controller in i.MX93 SoC is LCDIF. From hardware > design PoV, the parallel display format configuration logic is not a > part of LCDIF. Instead, it's a part of i.MX93 mediamix blk-ctrl. The > blk-ctrl includes controls for miscellaneous devices with small logics, > like this parallel display format configuration, LVDS Display > Bridge(LDB, see fsl,ldb.yaml) and so on. The below pipeline describes > data flow of a parallel display LCD panel: > > DRAM -> LCDIF -> parallel display format configuration -> LCD panel > > So, the parallel display format configuration appears to be a separate > bridge. > > > > > We do not create usually devices for single registers, because they > > are > > not a devices. Devices are a bit more complex - have some pin > > inputs/outputs, not a register only. Of course there are exception, > > but > > this one does not look like one. > > IMHO, this one is a standalone device although it is controlled by one > single register. It's input pins connect to LCDIF and output pins > connect to i.MX93 SoC's pins/pads. Fair enough. It needs to be defined as part of the mediamix blkctrl schema though. 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 16B77C636CD for ; Mon, 30 Jan 2023 21:40:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=L575zfSoWCgZCgF3oqSgNk81wKnN5155/rTKPoDEMZE=; b=gkzeApGNfmd411 GtYLCBC8dZJg0c7DPkiB0cTRdnt9/q0+haMHZMukXI0Dh1MyvFzNa57OHsMS52iYJctE8mU7hFzQN WIuJjZOGtANyTRQNuW498H6Co89WdoM2e+98NKwVHtIpeXT7RyZ7U5/f/25hK6+XQ4Kbvnb2siAo9 5DWBEEOOrANFInOnXqllgmXAM9sK5ILstj8SnfXvEBZ/p7zI51BcFnlUeTK6YQtOfByNWtghBpyl6 lth4wdNTUoF9w8oN8pQVAOPJvlxwtZQCYG3uPnMHtDviD2BlYASLXKqo9Iecrbdhy1Gy0C6tdup+c VNXoD0BdRlI4SRY1sMAQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pMbrs-005VxY-JK; Mon, 30 Jan 2023 21:39:12 +0000 Received: from mail-ot1-f48.google.com ([209.85.210.48]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pMbro-005VwZ-FN for linux-arm-kernel@lists.infradead.org; Mon, 30 Jan 2023 21:39:10 +0000 Received: by mail-ot1-f48.google.com with SMTP id 70-20020a9d084c000000b0068bccf754f1so1443333oty.7 for ; Mon, 30 Jan 2023 13:39:07 -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=JL/Sa/O/0qzbTgqvZA3y8OHGpThnTm0XwAphUFZl/lg=; b=ZNtzCZKTmUk97Vfvr3FYmeWhz4toIc2uCp0KGFxIUp6q8CNk/tgktnILgPa3zEJGDu ITlQvljXudPVFKDHdWQ96/S2xfTAxuzmgnaNt5uniVvhl5+aAhgPF8zJTfv/cHolJ/l7 bhz5nxE/N8CMgNhnboUqJdQrHf8K0s/mLz5CACsg1hwYYDH2qIzJB12qfxknUvZUCipL UPnmgN9LYdTlWop3dOghNDwUMaiggPhXZs/47dzVydVzdvFkswszHONwiqwkQQoEYbV6 wcV2CuTB2wUxx/SJSCmY/9CojWJthXOkgT+lwnnjL44gYXCz2MA/IMcAwufePkZ223nG fUpw== X-Gm-Message-State: AO0yUKVmpzonq0I6uNpIITh7NUDaswjfmyPjr2LRoAYVcGAh8c4qA4PT 4onthyytXN4Z1/zvVk+WZg== X-Google-Smtp-Source: AK7set/uccH7JTyE212LtTiDDrvQkFVU8TeUda5c03Xe15eIlmEojgcuEnr3VivOzcP4k0dxjP7f3g== X-Received: by 2002:a05:6830:2091:b0:686:56c6:34bd with SMTP id y17-20020a056830209100b0068656c634bdmr4701652otq.14.1675114746291; Mon, 30 Jan 2023 13:39:06 -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 w8-20020a9d5388000000b0068bbb73006bsm3642958otg.47.2023.01.30.13.39.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Jan 2023 13:39:05 -0800 (PST) Received: (nullmailer pid 3575008 invoked by uid 1000); Mon, 30 Jan 2023 21:39:04 -0000 Date: Mon, 30 Jan 2023 15:39:04 -0600 From: Rob Herring To: Liu Ying Cc: Krzysztof Kozlowski , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, andrzej.hajda@intel.com, neil.armstrong@linaro.org, robert.foss@linaro.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, airlied@gmail.com, daniel@ffwll.ch, krzysztof.kozlowski+dt@linaro.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com Subject: Re: [PATCH 1/2] dt-bindings: display: bridge: Add NXP i.MX93 parallel display format configuration Message-ID: <20230130213904.GA3569183-robh@kernel.org> References: <20230128034713.1530218-1-victor.liu@nxp.com> <20230128034713.1530218-2-victor.liu@nxp.com> <3c07b9bd-1981-2945-9efe-80afb0195de8@linaro.org> <87d6f54c4695330064eda295e258a0a5c3bc48f8.camel@nxp.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <87d6f54c4695330064eda295e258a0a5c3bc48f8.camel@nxp.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230130_133908_536787_BBAF8396 X-CRM114-Status: GOOD ( 29.85 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Jan 30, 2023 at 04:39:05PM +0800, Liu Ying wrote: > On Sun, 2023-01-29 at 12:46 +0100, Krzysztof Kozlowski wrote: > > On 28/01/2023 04:47, Liu Ying wrote: > > > NXP i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register > > > which > > > configures parallel display format by using the > > > "PARALLEL_DISP_FORMAT" > > > field. Add device tree bindings for the display format > > > configuration. > > > > > > Signed-off-by: Liu Ying > > > --- > > > .../display/bridge/nxp,imx93-pdfc.yaml | 78 > > > +++++++++++++++++++ > > > 1 file changed, 78 insertions(+) > > > create mode 100644 > > > Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > > > > diff --git > > > a/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > new file mode 100644 > > > index 000000000000..a84bfb46b01d > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/display/bridge/nxp,imx93- > > > pdfc.yaml > > > @@ -0,0 +1,78 @@ > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > > > +%YAML 1.2 > > > +--- > > > +$id: > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fschemas%2Fdisplay%2Fbridge%2Fnxp%2Cimx93-pdfc.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C7fb1b69849974435787008db01ee832c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638105896131701918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=kkX5B45NTsmDKKzxjOiE6MaE4zkMVbMe4ILammVSwMc%3D&reserved=0 > > > +$schema: > > > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fdevicetree.org%2Fmeta-schemas%2Fcore.yaml%23&data=05%7C01%7Cvictor.liu%40nxp.com%7C7fb1b69849974435787008db01ee832c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C638105896131701918%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=vIVpdEjIo6H3V8T7iTbDwz4Bmn0d%2BQB4BCJNJ0OzKJw%3D&reserved=0 > > > + > > > +title: NXP i.MX93 Parallel Display Format Configuration > > > + > > > +maintainers: > > > + - Liu Ying > > > + > > > +description: | > > > + The i.MX93 mediamix blk-ctrl contains one DISPLAY_MUX register > > > which > > > + configures parallel display format by using the > > > "PARALLEL_DISP_FORMAT" > > > + field. > > > + > > > +properties: > > > + compatible: > > > + const: nxp,imx93-pdfc > > > > > > Based on description, I have doubts this is a separate bridge device. > > Why this is not part of display driver/bindings? > > The relevant display controller in i.MX93 SoC is LCDIF. From hardware > design PoV, the parallel display format configuration logic is not a > part of LCDIF. Instead, it's a part of i.MX93 mediamix blk-ctrl. The > blk-ctrl includes controls for miscellaneous devices with small logics, > like this parallel display format configuration, LVDS Display > Bridge(LDB, see fsl,ldb.yaml) and so on. The below pipeline describes > data flow of a parallel display LCD panel: > > DRAM -> LCDIF -> parallel display format configuration -> LCD panel > > So, the parallel display format configuration appears to be a separate > bridge. > > > > > We do not create usually devices for single registers, because they > > are > > not a devices. Devices are a bit more complex - have some pin > > inputs/outputs, not a register only. Of course there are exception, > > but > > this one does not look like one. > > IMHO, this one is a standalone device although it is controlled by one > single register. It's input pins connect to LCDIF and output pins > connect to i.MX93 SoC's pins/pads. Fair enough. It needs to be defined as part of the mediamix blkctrl schema though. Rob _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel