Received: by 2002:a05:6358:d09b:b0:dc:cd0c:909e with SMTP id jc27csp6473539rwb; Mon, 14 Nov 2022 21:47:22 -0800 (PST) X-Google-Smtp-Source: AA0mqf5VgsmG0/QFlwNNLv9iaL8hAVL2FWPKJdKa08/WJlfvL49tr/qU2JqQ5SX47bLbwvGv7BjK X-Received: by 2002:a17:906:64a:b0:7ad:f0af:5b5b with SMTP id t10-20020a170906064a00b007adf0af5b5bmr12320340ejb.609.1668491242172; Mon, 14 Nov 2022 21:47:22 -0800 (PST) ARC-Seal: i=2; a=rsa-sha256; t=1668491242; cv=pass; d=google.com; s=arc-20160816; b=UOSf/B0+J4EzehGVBv4Zmjly98JIM5YqXewq35X7tjSlt4b+o1GrktowhQg7vdwVTw PNXrD5INg8bInDK5V2cMUKPE8m4Ua3RVCqA61hJrFPNn+MTsuLA6AuRwC37FHFnhXGbK O6FO9DybIdQkBbNyxIQWle8JtQkUjJZzQx1ug/q0BcT3H6F1cQ7RTa5eCkP/ENwjJRqA uqGMmkrN+j2Ih1HjhZi9O+fWVm9dNY9f0NZdvsULuLGanFmd3ZXyMj1Pb9ayDiDsafbE TOrLpnvml5KhBmrnVUHYEU4i2ZRKQ5picY3C+ugHfIhfXl53FvSKXH7+R8DGHr/Lejph kcCw== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:content-transfer-encoding :user-agent:references:in-reply-to:date:cc:to:from:subject :message-id:dkim-signature; bh=nJsbuqA1r87rIpqLjCuta7dYt7fGGZtIgd6uBRVHrAo=; b=B6JRdWJXmOeaXHbbCzsBKCmKyQvNPcTNwPjzpYyZYNycD4dEpXGAetjDhPXuGySZpd J9LL3kTBpEh+B1t4GTVImm4LZRBDjqPzk9UEh7MQosNTu6BeinXVYfN5+udJV0TSrglb 9iccxW0/JAvFj5Z+9iD52CmCQvUoz/M6pvqApMByDkNysk85cqB4i2IBNai1lPGlrY9h nPK9I4y8Ray4o3h9eeuEpbIMGjqFZceyAEnjVSsNfCsdNSP9vypsyLIPsYWU+ivl83ZD PI2Z6SRe6vyIS1SNMW1o8XrzBhethyjUE4u376FB+3Xzc/NB1vupa2vKO1OVnrBVWwMb YSWA== ARC-Authentication-Results: i=2; mx.google.com; dkim=pass header.i=@nxp.com header.s=selector2 header.b=qcVaqAuw; arc=pass (i=1 spf=pass spfdomain=nxp.com dkim=pass dkdomain=nxp.com dmarc=pass fromdomain=nxp.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nxp.com Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id s4-20020a17090699c400b0078df1c345dasi12192922ejn.534.2022.11.14.21.46.51; Mon, 14 Nov 2022 21:47:22 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@nxp.com header.s=selector2 header.b=qcVaqAuw; arc=pass (i=1 spf=pass spfdomain=nxp.com dkim=pass dkdomain=nxp.com dmarc=pass fromdomain=nxp.com); spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nxp.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231389AbiKOFWu (ORCPT + 89 others); Tue, 15 Nov 2022 00:22:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230517AbiKOFWs (ORCPT ); Tue, 15 Nov 2022 00:22:48 -0500 Received: from EUR03-DBA-obe.outbound.protection.outlook.com (mail-dbaeur03on2067.outbound.protection.outlook.com [40.107.104.67]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50F181BE90 for ; Mon, 14 Nov 2022 21:22:47 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Pt5921mS8PguJ+1qV7cdV0GNOh51Z0c9TKD7miWDSHWe566K/nEGxYYN15pAHXe3RazUCC2n88ZGu6uVBWbenZ9qLjoOd49K+oEbbAupst7CuT09V2cTXZlMj4TQnUxvPtyuCqCx9J7v27ws9h/AQQD/My2HWFppWC84XG3UbRj2NiFXMVJhqE50L4h39jc7houxOJ3DJ3tzq/kac8PPIUNp1V8tjIc3aPT1Q2KsooiIqYaN8KZRalYygB2qWdEpdp8wTYEzG9K97GF4ugU8Ld3r4qY2JxlcKs5d0vlhwHPIyFkSGluGMHgaX2BA3++5FQnscGtiYmzLB+h4qLn8RA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=nJsbuqA1r87rIpqLjCuta7dYt7fGGZtIgd6uBRVHrAo=; b=Lv8p0gsXb2R+AVRPW5vYlHsTjSfEBkUWWO9/Wrja3DhPnbZU0wAI5l96+oDOEmO2R62mod2mJQrjtPaD+a0G/wpmdRdrAeldKAyPnXj3BMz69UOvZHAHugClUh+taDZN0/6tvKcWPTnSKWD8kFUfCX5v16H6Xe5rKeMmMJiNIG6+UH0gAH5i2C3F/gc3SE4xLYNHTdYmyVVRrx1yqGERV0Et6NbmqHwix9g9k0Hre3xNqHqlernMxM7IZXE+09KvFaLvU4yyxYsWDTHPMma1L0ZxvrsgHR25n5MiiIk+Fce7JpmsM552dftnNEqVBSUmTmvbrAvpXeX/acbRgsTiog== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com; dkim=pass header.d=nxp.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nxp.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=nJsbuqA1r87rIpqLjCuta7dYt7fGGZtIgd6uBRVHrAo=; b=qcVaqAuwJdO2iOKG5LExZpaTnZxqWkJFgnLUhoXVcWjRfM+2WUWsLCSg+NchF4OUWwU73LT05edAmXs8dpgfa4vC2kLk3HdMevJIXQ09bk1g5AIDQ5+JWjJiUBkEbko0oBsTnEYS2QfuV2RkReunB7IQnW/Fv2tB94owCRJOscA= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nxp.com; Received: from AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) by DU2PR04MB9523.eurprd04.prod.outlook.com (2603:10a6:10:2f6::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5813.13; Tue, 15 Nov 2022 05:22:45 +0000 Received: from AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::dcca:b62f:206b:dcf8]) by AM7PR04MB7046.eurprd04.prod.outlook.com ([fe80::dcca:b62f:206b:dcf8%3]) with mapi id 15.20.5813.018; Tue, 15 Nov 2022 05:22:44 +0000 Message-ID: Subject: Re: [PATCH RESEND] mfd: Add Freescale i.MX8qxp Control and Status Registers (CSR) module driver From: Liu Ying To: Rob Herring Cc: Lee Jones , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com Date: Tue, 15 Nov 2022 13:21:58 +0800 In-Reply-To: References: <20221017075702.4182846-1-victor.liu@nxp.com> <4dfb7699c33974a682d798071c85b431b87e5432.camel@nxp.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.4-0ubuntu1 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SI2PR01CA0031.apcprd01.prod.exchangelabs.com (2603:1096:4:192::11) To AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: AM7PR04MB7046:EE_|DU2PR04MB9523:EE_ X-MS-Office365-Filtering-Correlation-Id: d40fd252-a612-4c70-2399-08dac6c96cde X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:AM7PR04MB7046.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230022)(4636009)(366004)(39860400002)(396003)(136003)(346002)(376002)(451199015)(83380400001)(5660300002)(186003)(41300700001)(2616005)(4326008)(6506007)(36756003)(8676002)(66556008)(66476007)(26005)(66946007)(52116002)(6512007)(53546011)(6486002)(8936002)(478600001)(6916009)(316002)(38350700002)(38100700002)(2906002)(6666004)(86362001)(4001150100001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?ZktQa3FaMmU4b0tWcHlRZ1d5OUswQXlybHBlOEVNaWJ5N21HWWFDSndVRGhu?= =?utf-8?B?VmtaUVMxaitqREtvYzVqcmJxWmJWaHp5aE0yUFhNK2ZMMDJNUE1LZ3RCN0VT?= =?utf-8?B?ZU1GaDNEN1VEdzdDa0NHcVhMb1ZMYk5wc3QwaWRXN1pWVWtFN0V6MldiMDYw?= =?utf-8?B?bmU3czBZaUtSc3NJVURjZm85YzJydG5wVG52bG9rcUlLejBINm5lazJZRzcv?= =?utf-8?B?Nk5IcWxxNU9iVUY4VUNDVGUwWmJZenFia3VIc21qNEZkK2M1TExEYjJzZzVr?= =?utf-8?B?WVF0RDYvWjJhV1NHUXg3WWpnY25BZFRwUC9FZ3pWeElYVUZ0cDIvV1dScEEx?= =?utf-8?B?SC9SUk9LYUhRQVU1NXF2QTgvWTJKdFBUS3ZIU0V4MlJWeWY5MXFibVNpcVlY?= =?utf-8?B?U1A5eE9jMG9RVGJ1UVZob2ovMHdTWDlORmIrSVhjMHRTT0ROZVdIbDVvYW5i?= =?utf-8?B?WTE0MnhFVnp6aVpRMW1adS9yWExYTzJFRnd3bmMxOG5QZm5rVjlaYmF4aWpo?= =?utf-8?B?Z2MxZ0FkdjJVbncxR0x0a3lJN2VaTUphVmZPbDRUdHFrN3BweDNkcExJOXB6?= =?utf-8?B?TVArejhFdXF2M2xZWVFYeXlKNUw2QzE0UFJtNHoyaytLOUxSTkp0ZGxHdkJV?= =?utf-8?B?aW9TWEt3RHNtbDJ3YzhTSXVmS29qa2Z0eGxYQ0VGdjh0TXhRc0VBS01QYmZE?= =?utf-8?B?QzMrdTdjbUxIeGJwUkVlQk02aEN6NmVFWDgwdFV0d0czV0QrQUEzQkNxZ1U4?= =?utf-8?B?bkh4cVhCaE4xWjhxN1V3eGkvTXRjY3ZicGcyeTcvOGx4S3JiSGRxRThqeHhP?= =?utf-8?B?OU83TDNMVmE5YkM4U0t5WDZNeTlHcmJkMlljVlgyNmJPb2dkM2ZJeUU2UDkv?= =?utf-8?B?UnBoQ3VEbWFpZ3NnYU8xSXRHaHJsTkxKcmFHU1prTVlmWHhSVGtHQTNXbHBl?= =?utf-8?B?VVp0U2FtSXFsUHZ6Szl4M0xleklsMmp4Z3FEYUErdFVCZXJLQkMydE5BZmk3?= =?utf-8?B?RjJvT3JTUndvT082TktwRFZjYzZ3VmFVUVhuSHdmR1hSK1ZXTStUaGlzMkFS?= =?utf-8?B?VTdkaTVXejdMWUVvcHFBL0xHNDE0Snk3VHJJZmk1TkIrQ00rdFFQWW81ZGFY?= =?utf-8?B?YXZVWUdEOVVtK0s2MWFUeEFuRG9iVFppbm5rWm83SkFFVHQzQ3ZwZmRvYWJO?= =?utf-8?B?RDNIUjcxbEsxQ2pEaDRocTBlV0ZLeHBRajI5dmxlUC90RlJYMXc5L2J1bzNC?= =?utf-8?B?cWFhU1V3U0dhUEpEZURKazdXSXhxTDR2UzMwWENxeEZtaVB5WWVoUTVtUHRj?= =?utf-8?B?SDVBd2xCckdyWEVtYlRLOGZTM3I3V05QRXRERWtZL3VYdXp3Sk1NUU1sTDZC?= =?utf-8?B?RG1uVktSZW9DNTdTQUpTdWFLQ0dCRjUxMlFqT2tWbzIvT1FpTzFFWTlEdmxp?= =?utf-8?B?Zzh5ZWhQQkhXRHRMMnpBNEpFbVpycEE2YVRTb09DN01tWVNQdnB5Mk81VlNU?= =?utf-8?B?Z2UzbjBMbEgyZi9DaXlQdG11ZExybU1DcFRUZTZqMkNKdEl2ajZqTHdoOVBH?= =?utf-8?B?djlNT1FpWnNOSTlGejlIR3dIK3pVOWtOak5lRWkvdFg5QmRCSWYrOE9CSDJB?= =?utf-8?B?Q0RwS3lGWFhWbUNWcGE3QnNrVXhlSFZWNWszVnE5eDlma0hVTnpNOW5mNWpv?= =?utf-8?B?MHVPYVVLbHNyMmQ3UnBsSjBrSXdkSHl4OTF6bm10NVdSb3BOQ3VhUENSQ1h3?= =?utf-8?B?UUpLelpYSGVwalNUTXRWdm1uWnRQLy9USHJHOEcxSWpwNnNpNTdjMXFNb0xE?= =?utf-8?B?MVB4SGFBMktaU29hc1ZWRFJucXovR2lIZm1vNHJpaFlQRTBsb3l1ODJUUXMy?= =?utf-8?B?dzFqR285eEhvQ2d2d1ZFQ2VKd3prMWlYKzBadGphUU8rdlRSYUgvUnA0Sms4?= =?utf-8?B?ZlhGcWExQnpXVW45bjVYMUlCM2RqRHdRQmJTa0VrNjI3bEg4YUdRV1VjblFv?= =?utf-8?B?WDVkL2hxYnVPY1lJTmZuMW03U3ZYdXJSUkNxb1N3eFFucktDQmZsVkh6OHll?= =?utf-8?B?bGVmSEZLWWNTUDc3QlhiNDZ2dlNLdkpITnR5Z0V2cGV6K256ZXhGVEQrZzdu?= =?utf-8?Q?+/aSKhjXWyKV0TstLWphKGk2l?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: d40fd252-a612-4c70-2399-08dac6c96cde X-MS-Exchange-CrossTenant-AuthSource: AM7PR04MB7046.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Nov 2022 05:22:44.6550 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: N5mAs29NG+x3wv8N3oAe90cBHI8wD7SHCdBBYH/ecHBgxR5MokeWMXiTDz5hxNr++XsN1B6ibG4cJhrZROn0Zw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DU2PR04MB9523 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2022-11-14 at 14:54 -0600, Rob Herring wrote: > On Mon, Nov 7, 2022 at 9:58 PM Liu Ying wrote: > > Hi Lee, > > > > On Mon, 2022-11-07 at 09:05 +0000, Lee Jones wrote: > > > On Wed, 02 Nov 2022, Liu Ying wrote: > > > > > > > Hi Lee, > > > > > > > > On Tue, 2022-11-01 at 13:53 +0800, Liu Ying wrote: > > > > > Hi Lee, > > > > > > > > > > On Mon, 2022-10-31 at 15:40 +0000, Lee Jones wrote: > > > > > > On Mon, 17 Oct 2022, Liu Ying wrote: > > > > > > > > > > > > > Freescale i.MX8qxp Control and Status Registers (CSR) module is a > > > > > > > system > > > > > > > controller. It represents a set of miscellaneous registers of a > > > > > > > specific > > > > > > > subsystem. It may provide control and/or status report interfaces > > > > > > > to a > > > > > > > mix of standalone hardware devices within that subsystem. > > > > > > > > > > > > > > The CSR module in i.MX8qm/qxp SoCs is a child node of a simple > > > > > > > power-managed > > > > > > > bus(i.MX8qxp pixel link MSI bus). To propagate power management > > > > > > > operations > > > > > > > of the CSR module's child devices to that simple power-managed > > > > > > > bus, add a > > > > > > > dedicated driver for the CSR module. Also, the driver would > > > > > > > populate the CSR > > > > > > > module's child devices. > > > > > > > > > > > > > > Signed-off-by: Liu Ying > > > > > > > --- > > > > > > > The Freescale i.MX8qxp CSR DT bindings is at > > > > > > > Documentation/devicetree/bindings/mfd/fsl,imx8qxp-csr.yaml. > > > > > > > > > > > > > > Resend the patch based on v6.1-rc1. > > > > > > > > > > > > > > drivers/mfd/Kconfig | 10 +++++++ > > > > > > > drivers/mfd/Makefile | 1 + > > > > > > > drivers/mfd/fsl-imx8qxp-csr.c | 53 > > > > > > > +++++++++++++++++++++++++++++++++++ > > > > > > > 3 files changed, 64 insertions(+) > > > > > > > create mode 100644 drivers/mfd/fsl-imx8qxp-csr.c > > > > > > > > > > [...] > > > > > > > > > > > > diff --git a/drivers/mfd/fsl-imx8qxp-csr.c b/drivers/mfd/fsl- > > > > > > > imx8qxp-csr.c > > > > > > > new file mode 100644 > > > > > > > index 000000000000..3915d3d6ca65 > > > > > > > --- /dev/null > > > > > > > +++ b/drivers/mfd/fsl-imx8qxp-csr.c > > > > > > > @@ -0,0 +1,53 @@ > > > > > > > +// SPDX-License-Identifier: GPL-2.0+ > > > > > > > + > > > > > > > +/* > > > > > > > + * Copyright 2022 NXP > > > > > > > + */ > > > > > > > + > > > > > > > +#include > > > > > > > +#include > > > > > > > +#include > > > > > > > +#include > > > > > > > + > > > > > > > +static int imx8qxp_csr_probe(struct platform_device *pdev) > > > > > > > +{ > > > > > > > + int ret; > > > > > > > + > > > > > > > + pm_runtime_enable(&pdev->dev); > > > > > > > + > > > > > > > + ret = devm_of_platform_populate(&pdev->dev); > > > > > > > > > > > > The use of this API does not constitute a MFD. > > > > > > > > > > > > Please use "simple-mfd" instead. > > > > > > > > > > simple-mfd devices have "ONLY_BUS" set in simple-pm-bus.c, so the > > > > > simple-pm-bus driver would not populate child devices of simple-mfd > > > > > devices. > > > > > > Right, simple-pm-bus will not populate child devices, because: > > > > simple-pm-bus.c may populate child devices of simple-pm-bus devices > > because "ONLY_BUS" is _not_ set for simple-pm-bus devices. > > > > simple-pm-bus.c would _not_ populate child devices of simple-mfd > > devices because "ONLY_BUS" is set for simple-mfd devices. > > > > > /* > > > * These are transparent bus devices (not simple-pm-bus matches) that > > > * have their child nodes populated automatically. So, don't need to > > > * do anything more. We only match with the device if this driver is > > > * the most specific match because we don't want to incorrectly bind to > > > * a device that has a more specific driver. > > > */ > > > > > > So "simple-mfd" must be populated elsewhere i.e. drivers/of/platform.c. > > > > If simple-mfd device is a child device of one device listed in > > of_default_bus_match_table[], then it may be populated by > > drivers/of/platform.c. But, in my case, simple-mfd device is a child > > device of simple-pm-bus device(not listed in that table), so it will > > not be populated by drivers/of/platform.c. Instead, > > drivers/bus/simple-pm-bus.c would populate the simple-mfd device. > > > > > > > Also, the simple-pm-bus driver would not enable runtime > > > > > power management for simple-mfd devices due to "ONLY_BUS", which > > > > > means it would not propagate power management operations from child > > > > > devices of simple-mfd devices to parent devices of simple-mfd > > > > > devices. That's why a dedicated fsl-imx8qxp-csr driver is needed. > > > > > > This is more of an issue. > > > > > > Why can't this device use "simple-pm-bus" to have support for both > > > auto-registration AND Runtime PM? > > > > If I change the compatible string of the CSR module from > > "fsl,imx8qxp-mipi-lvds-csr", "syscon", "simple-mfd" > > to > > "fsl,imx8qxp-mipi-lvds-csr", "syscon", "simple-pm-bus", > > all devices I'm interested in are populated and all relevant drivers > > can probe. But, this change makes 'make dt_binding_check' for the > > existing fsl,imx8qxp-csr.yaml fail: > > As 'simple-bus' is for MMIO devices, so is 'simple-pm-bus' with the > addition of PM capabilities. That means you have registers defined > (reg), but you don't. > > Either you have a block with mixed functions or you have separate > blocks. If the register space is all mixed together, then it is the > former and an MFD. Don't be designing your binding based on Linux > behavior. Thanks for clarifying how to differetiate MFD and 'simple-bus'/'simple- pm-bus'. I would say the register space of the CSR module is mixed together, e.g., LVDS PHY child device has a register offset 0x00, PXL2DPI child device has a register offset 0x40 and LDB child device has register offsets 0x20 and 0xe0 in i.MX8qxp MIPI DSI/LVDS combo subsystem CSR module register space. So, it appears to be a MFD. Lee, what do you think? If it is indeed an MFD, a new MFD driver for the CSR module is needed then. Regards, Liu Ying