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 72C4DC4332F for ; Sun, 5 Nov 2023 15:51:40 +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:MIME-Version:In-Reply-To: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=nb2HCuuuwo0+JMIIRL5uI22PT/Rh5heAE+7zCZDPxJo=; b=V4doTEi1knWkeA OiO+3Ud5SHXOytNhdXo1kqyym7OThA3CdlLWHUtjY5eVjpMYa7XCI8dXsI0YNhSo7Wujn242ySoFT JtuQFxov0UvYLVA6Im+PB/ff/E/ZibVwPdP7yBaB1mpYcDbJ089MjR0pn8hqIP+2hRocFGgWxADZp W7/xpDvJlFrSVZO4ev0puD0h984bupBIItpJLHadhrH5kBwLxNjjveBg6Z7TcxHeqOJCk02L8oxlw JAKrKGJtauZKMvESNC7lKh5UD97/hkWWfZtNJPMIzPG6+a1c1xfrEC1h4pB8YQJmIyCcEqU5IPweN 2YvfzxcrVG5RjEqiST3Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qzfPX-00F7vJ-2f; Sun, 05 Nov 2023 15:51:39 +0000 Received: from mail-vi1eur04on0623.outbound.protection.outlook.com ([2a01:111:f400:fe0e::623] helo=EUR04-VI1-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qzfPV-00F7uR-1N for linux-i3c@lists.infradead.org; Sun, 05 Nov 2023 15:51:39 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=JDdKLQvKv5KyYzKh9s9IGhiL1+QAXGh0rTicXrZ5EaOLiXcclctE8GaUt3Wwydcs37wZ1OJaCzeaMPFPLTn9YMRWS6nzRO4OVfHmCEAS8e8bkALu2UEjOi+yDrGZrHl8JQQsVVqTMlCNA9DyHRvLldNTxW/D/8yjBHu+WZaVOzXNELNcG1LiaMNjWk4hxM759ydn44eP28vl8l0AauyPrMbGHJG2KwxE4xIS+hICRBJBqhnEVFpTUtcJ42q/+Ery2bbj9TWSr8PT/8pq/pZHgnLxmQbfCuEJ9sp+80uJ4maWito/gZ1IsFaYHEgRtmAk5vF2Juh2en/wv48BXCRuGg== 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=qEh9gN5qE3yQe+vn+12QjSRTTZxQK3bGFlEzGq1KHGE=; b=XYyPrGPDJ36MlMTiAyLDDLKIT/vlvgnSQSU7jXJJNQRxPriscad9S4dSmmAwoEn+8oewTwOPIskBRMRSAGewVCqaI4dXhL1TMGbi20aHiEkaZkRLsgNwnKeYNiSQy5Sk2OIXXYlY5H9sycsrsjNi5OIOmWBxYebuDWgYRstd0eiKeXQl+kjndQ/t4jNogic3uRpvF3vdCE3Hgg8WmtAglsIE6UhhQntTAa+oeQmB3AZEqSLtUazm8XCSrG7+Apy3+Bn3AWQU01EDczrP5gOy7UjhLVrz4r4DW9Ojt3bUds0rTOk1rnGVROYxHZxG8LLTgJwI0fVKU/gKo6ZPCrEHxg== 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=qEh9gN5qE3yQe+vn+12QjSRTTZxQK3bGFlEzGq1KHGE=; b=InI0kL6Dbtb4aWMNTVOL7rj1GMn53215zvHV9BIIxKFn/rR3FP7OvTI1O3q/cR89VjOMUslhrMP6h7yBZIGghhfxE8haoTVpg7un4jVN7SHPZTAUPDhcngBVtXW38pADOSMrvtqqm7aTUu+tl5I0U5IWe3++4KUnuKTd5DJXeV4= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nxp.com; Received: from AM6PR04MB4838.eurprd04.prod.outlook.com (2603:10a6:20b:4::16) by AS8PR04MB8914.eurprd04.prod.outlook.com (2603:10a6:20b:42d::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6977.11; Sun, 5 Nov 2023 15:36:54 +0000 Received: from AM6PR04MB4838.eurprd04.prod.outlook.com ([fe80::2635:52a:c866:2576]) by AM6PR04MB4838.eurprd04.prod.outlook.com ([fe80::2635:52a:c866:2576%6]) with mapi id 15.20.6977.013; Sun, 5 Nov 2023 15:36:54 +0000 Date: Sun, 5 Nov 2023 10:36:46 -0500 From: Frank Li To: "Zbigniew, Lukwinski" Cc: Alexandre Belloni , Miquel Raynal , conor.culhane@silvaco.com, imx@lists.linux.dev, joe@perches.com, linux-i3c@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/6] i3c: master: add enable(disable) hot join in sys entry Message-ID: References: <20231018205929.3435110-1-Frank.Li@nxp.com> <20231018205929.3435110-2-Frank.Li@nxp.com> <57efe6de-cf65-32ed-fd1e-a388e1676c70@linux.intel.com> <20231020154528.2f5f68f5@xps-13> <20231020163348.1752167d@xps-13> <8a7ac52e-f102-6f5e-35ab-217e6ecc6ba5@linux.intel.com> <20231020202519b2449707@mail.local> <86955c20-22e6-0d02-813f-02f0096c2819@linux.intel.com> Content-Disposition: inline In-Reply-To: <86955c20-22e6-0d02-813f-02f0096c2819@linux.intel.com> X-ClientProxiedBy: SJ0PR03CA0199.namprd03.prod.outlook.com (2603:10b6:a03:2ef::24) To AM6PR04MB4838.eurprd04.prod.outlook.com (2603:10a6:20b:4::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: AM6PR04MB4838:EE_|AS8PR04MB8914:EE_ X-MS-Office365-Filtering-Correlation-Id: 254fe1b7-1625-43d7-98d1-08dbde1509a8 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: QuCn8qKV5vtpcVZ3euvx7w2sGfyZfmQgO6DV7BlxOIaDvpy4mDTcRMCK0UlzQDs1jTqyixrJMj2TpBE8i0VRKyX9HQskTeo4X4HekdYYz6PUS0Mc4Vzc3ZTJjp5jl3GTv/nMgwVxtdG/r65M3R/Blr6SQVyyanhX0XVt2rZwbmfAXrJyG77dOtQA/Xznz4c3HFuskA03jrS8v1erkfxYO4g6nGfZc2JLorAmGvqRE+vk1j7ez6evy9XJU8VoMm6LyXmLbcdnvG+HkmD7pWCDq5DNoZBTNcibB4bc2oEwrZQk8BQmeqGK1otrqXGdKR8nQX9MM7770kwl3TiUGOxt1dVUR6kM/2oYGZkPp+ABIIMFl2Na38UbcjxRR33conQPZyuMyhYNsfMoTy1tMubITHi3buM4MhjtlUemmUAM1HtQNUYXZQt7mtvm/nloJN6rqeC3izegi9NGXzgJtzNX0vAv7Hfxx2gcvk2js2v7EYbRe/rrfW+V9/e5uIRwjkbFH2L6CX9houCc3uoHTLZWap1kuQQyk3OBACg5vLlMzCRFV/c8/itD7ALK+6RJbC1J8vFD8eNXvLVlzWcnqSuIqMqRrTzftYm5HOrVRBXJnys= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:AM6PR04MB4838.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(7916004)(376002)(136003)(39860400002)(396003)(366004)(346002)(230922051799003)(64100799003)(1800799009)(451199024)(186009)(33716001)(6512007)(6506007)(5660300002)(86362001)(38100700002)(53546011)(8936002)(478600001)(316002)(41300700001)(52116002)(66946007)(66476007)(2906002)(966005)(9686003)(66574015)(26005)(6666004)(4326008)(54906003)(8676002)(6916009)(6486002)(66556008)(83380400001)(38350700005);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?iso-8859-1?Q?SSXxq4aywfyTR3CIbelK3bmMvKOnCduEhiYHeyG44u14oJCf0c1SbLK/gF?= =?iso-8859-1?Q?Mg2b5f8RVq3TXEjMIhLfSL0S/EA7hbT2sHbwRTveHlWQGQTuwopzwYxVFb?= =?iso-8859-1?Q?1vMo5IH7jajUh8AVvGLW95wZrl52sjIWkfgw1Sms8Ipvt7cnjW/pHZbxwe?= =?iso-8859-1?Q?b0cGHnG428boADvLVTYfA1QG8aPbYVsjYaWb+npmU91f8k19+RzgiajXzc?= =?iso-8859-1?Q?yA3TQ1NTYhpqww4t1RNO8G1wsxL+4A6xE3sZbJb6eNEbvC/HgSshOFTyfY?= =?iso-8859-1?Q?WM38OiH2GF2c6Ol/f+N1HAEaO/A9mFyvoeJJku6gXzww+0M7jYfJK+X7mh?= =?iso-8859-1?Q?7Q9ln9nr/LHTS034RIjXld/NswrqqZTDimeDwjPldaSxJxegCJVZuj6goI?= =?iso-8859-1?Q?AaFlMp3PenkFn0Ddp0LGAK2HiDhawNDKfQb1iAbuRQRsv2HtlvCW7zUeZ1?= =?iso-8859-1?Q?QLz6wMlP1S9U0oGJ3HhWfR7dgWnInrqlooS40Ot6EjJnnXr0LGYEUtgT6F?= =?iso-8859-1?Q?nhat537LdNjs+HyEMwyyXBy8IN6RYokZ1rHC1t+9JYQte5EC4ytTbTWgK+?= =?iso-8859-1?Q?MLzfmLK1vWoz9c3R9HNsyuf63/OWFWqogvzw2gLel4CI8dLxAUpsGeqENr?= =?iso-8859-1?Q?+96g9vtz66fPDahfbuEKDcGZlp7i7Kh1/2im4QDZGs83Fnoq3fJQ5gy2k9?= =?iso-8859-1?Q?S/edMtvCRNY176oul3cNjKrEYfnTpnKzkTT3Rp1o+vLWNdIy9HHKagyYiG?= =?iso-8859-1?Q?gEpk9phsxyThaxL1s9KVzONKPM6FLlTSzHsuveDfw9l/wiRyMmJOvY2IM7?= =?iso-8859-1?Q?w6IgMzfQ2Q+GUqfbwYm56bmL/eNTKmNCaiUCKcCDP0eKa+DOVozlF+3aw3?= =?iso-8859-1?Q?wvFP6aprvSh0Yr3mEerKVQNYXHpJaSbLgM2x1Q7ZkUAa14EuUYFXqKavs3?= =?iso-8859-1?Q?dVNlFkhbl82x9YEzLRU+zJM+L3cYW6QKHK62t4VLs4+wjQQ64hMR8fA34X?= =?iso-8859-1?Q?XY8NWwLW6SfBiuL6Oa9SxNIDvR7QRjmP8/hQQQrFR1Ged2V1/4ucdcsKAf?= =?iso-8859-1?Q?oOw2Q+QGkqLlcRP8dHZgChjjlCaJfXyL54ddRUeCtcRxxjDEdhvlYllhSo?= =?iso-8859-1?Q?nI31eunRT5sxlbLwbZ4oIU2GEYYMYTddGi4T5v6JTmnmX4zI/HjH41ItXa?= =?iso-8859-1?Q?V8p95wdzdjnzHNaBv3+XMtChG02o3yenkNQ2MJ2JzpF1NEXp9IcXJcEUsk?= =?iso-8859-1?Q?Lmgs3uHgWvnZILRXVltYQ7HTyRvbxtmS7aNSjQqVpeyVPTcYKD7s2nXnXu?= =?iso-8859-1?Q?fYsOg1EfHP7D0Z7BsF3hV9S647epHyUYoODS9zySncRHNxP/NdHOlBI1NS?= =?iso-8859-1?Q?hq0oP3bqv51e5K26Wq/5kCrZhnbVwNMK6IQmZpsDg5il8LsUzmsJCn6/EM?= =?iso-8859-1?Q?WmY9enonIOG8rwKv+bvwGZSjUhomE3u7JIE12meP7ZhtvoB23/fXyXa9u6?= =?iso-8859-1?Q?b0Yp2+DLQQjU45c/5jBzbmBY3nnNzq1GjwsW+e2IQ2kr5ppUfJvWt6lwlg?= =?iso-8859-1?Q?nega7XkJr7EybGAhwLHKLCKA+5DTNNbYDBZU70iabE6zqkvlRWM8MNRPKX?= =?iso-8859-1?Q?G5OYk0trVgJeE=3D?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 254fe1b7-1625-43d7-98d1-08dbde1509a8 X-MS-Exchange-CrossTenant-AuthSource: AM6PR04MB4838.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Nov 2023 15:36:54.2409 (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: ajnpoXlMfLdiMXvTte54meBlTUrvsMjrfg4FLIFpPmvec0PejZDKhYyCUGIUWtAkk7mU9ooKEvrmmTYaCO1itA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR04MB8914 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231105_075137_464280_9A5355BF X-CRM114-Status: GOOD ( 38.15 ) X-BeenThere: linux-i3c@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="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-i3c" Errors-To: linux-i3c-bounces+linux-i3c=archiver.kernel.org@lists.infradead.org On Fri, Oct 20, 2023 at 10:42:20PM +0200, Zbigniew, Lukwinski wrote: > On 10/20/2023 10:36 PM, Frank Li wrote: > > On Fri, Oct 20, 2023 at 10:25:19PM +0200, Alexandre Belloni wrote: > > > On 20/10/2023 17:12:53+0200, Zbigniew, Lukwinski wrote: > > > > On 10/20/2023 4:33 PM, Miquel Raynal wrote: > > > > > Hi Frank, > > > > > = > > > > > Frank.li@nxp.com wrote on Fri, 20 Oct 2023 10:20:57 -0400: > > > > > = > > > > > > On Fri, Oct 20, 2023 at 03:45:28PM +0200, Miquel Raynal wrote: > > > > > > > Hi Lukwinski, > > > > > > > = > > > > > > > zbigniew.lukwinski@linux.intel.com wrote on Fri, 20 Oct 2023= 10:55:27 > > > > > > > +0200: > > > > > > > > On 10/18/2023 10:59 PM, Frank Li wrote: > > > > > > > > > Add hotjoin entry in sys file system allow user enable/di= sable hotjoin > > > > > > > > > feature. > > > > > > > > > = > > > > > > > > > Add (*enable(disable)_hotjoin)() to i3c_master_controller= _ops. > > > > > > > > > Add api i3c_master_enable(disable)_hotjoin(); > > > > > > > > What is the use case for having HJ enable knob in sysfs ava= ilable for user space other than for debug stuff? In other words, does user= space really need to enable/disable HJ in runtime for other reason but deb= ug? If it is only for debug maybe it=A0 could be move to debugFS? > > > > > > > I don't think hotjoin should be considered as a debug feature= . The > > > > > > > problem here is the power consumption which is higher if you = enable > > > > > > > this feature (you need to keep everything clocked and ready t= o handle > > > > > > > an IBI) whereas if your design is "fixed" (more like an I2C b= us) you > > > > > > > may save power by disabling this feature. > > > > > > > = > > > > > > > A module parameter does not fit here because it's a per-bus > > > > > > > configuration. > > > > > > I agree. sys entry is more flexiable. and let controller choose= better > > > > > > power saving policy for difference user case. > > > > > Maybe it's not the first time this case is faced, would you mind > > > > > including power management maintainers in this discussion? Perhap= s they > > > > > might have pointers or even have the solution already. > > > > = > > > > I did not mind HJ as debug feature. But enabling / disabling the HJ= sounds > > > > to me like debug option. > > > > = > > > > So the flow you are considering here is like this:? > > > > = > > > > 1. system boot with HJ enabled, so HJ works during initial bus > > > > discovery > > > > 2. some entity in user space decides to disable HJ because pow= er > > > > consumption? > > > > 3. some entity in use space decide some time later to re-enabl= e HJ > > > > because some reason? > > > > = > > > > I am just wondering whether there is real use case when you starts = with HJ > > > > enabled and than disable it > > = > > I think it is validate user case. Assume a I3C GPS device, user only use > > it when open map. Before map application open, enable i3c hotjoin and > > power on GPS module. After map application close, disable i3c hotjoin a= nd > > power off GPS module. > > = > Got it. I think we are on the same page. Thanks for explanations! > > Frank Does everyone agree on this method? If still need further discusion, I can repost patch 3-6, which is independent on these. Frank Li = > > = > > > > = > > > > in runtime or start with HJ disabled and enable it in runtime. If y= ou are > > > > taking care about power saving > > > > = > > > > =A0let's keep HJ disabled all the time. Default state for HJ could= be > > > > controlled by DT entry. > > > > = > > > = > > > This would be HW configuration and not HW description. > > = > > Yes, DT maintainer may not accept this entry because it is not HW > > description. > > = > Sure. Makes sense. > > > = > > > = > > > > = > > > > > Thanks, > > > > > Miqu=E8l > > > = > > > -- = > > > Alexandre Belloni, co-owner and COO, Bootlin > > > Embedded Linux and Kernel engineering > > > https://bootlin.com > = -- = linux-i3c mailing list linux-i3c@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-i3c