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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 7897BC63697 for ; Thu, 19 Nov 2020 16:23:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 07F81221EB for ; Thu, 19 Nov 2020 16:23:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=nxp.com header.i=@nxp.com header.b="cQydBVBV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727769AbgKSQWt (ORCPT ); Thu, 19 Nov 2020 11:22:49 -0500 Received: from mail-eopbgr70080.outbound.protection.outlook.com ([40.107.7.80]:61234 "EHLO EUR04-HE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725877AbgKSQWs (ORCPT ); Thu, 19 Nov 2020 11:22:48 -0500 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Yv+XQKzwa1xCA2yd6r2Q2T8XZFk+GfH4uSlwU0e9y1W+BmdazRMhC8AkZWCyzfw/Oe+VFdhFkU2f2klHNDgjHfdRft3FAWJcfp5Pwfn7JvR7KamnFf1PemOPmBMNsGRPV6Q/4gp4zn+GErHluFOZRGDNjT2zBgqrctg3eKFqZJ0d/2O/3XL0ItChHWp0Q/WPEsM2E8hlXrRgvvPsnDo7wL8UIUE5dHILb4aJvCL0rfXceoiFo1unVmx290MKmNum/dr8gH5LYZTLFmebTbw1MrosR5TmWejidICTHyZnlhS6SP4SvkIJlAQ6713Q7kwyvJmsmBGqxZQfNvqNWq//jQ== 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-SenderADCheck; bh=Xk8PqfV29i4MMVarWkzfSNBN2Se8XqxJqn1s4iSK1ZI=; b=DiySKbotiX2elSvbbB7aB/ZFRKRkd/iMs/B2nAdZyPYqGm04gH+r5uJX+8EMfdLgB0nfJK1D0cjkx/uTxG/xZk5ICl0t1nUT3LVg2268q44HZ3gQAvj+u7z7vQzeCdhgn3mE3cwRVWfzK2aMztJkDdb95itvL0+j907G1BILaQWwHN0JVqcZlhCOK4EHAkkNd2ES9WeN3ZLEcaFVvn2kg1vGuETtHFMiM7aIzelH+9qcHwihLBQ/B/pVklqWgEiSDWImi7IKR1oM5g3ckwQUt8Lhir9x779GCGj3Kezxg3PbrBDVSUV3pR/C/HjiS/CzegQPJrRVezPxmothv9s8JQ== 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=Xk8PqfV29i4MMVarWkzfSNBN2Se8XqxJqn1s4iSK1ZI=; b=cQydBVBVjGSmF4mjQP5LJNjZ7eX63KuP30HVkTYoKYak50HEPbxemQDFaPJ6Yq8LN5a5lqE4FLAdCEg/LiEEMscgHF24zEHoi82ndrRHMhjf4XaztN6y8s6D6fy+sZJ7HteerGDpnO2Z5/HCcYiwDzQE7gDZ+BI4ZooxRDx9K2U= Received: from VI1PR0401MB2272.eurprd04.prod.outlook.com (2603:10a6:800:31::12) by VI1PR0402MB3488.eurprd04.prod.outlook.com (2603:10a6:803:10::29) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3564.25; Thu, 19 Nov 2020 16:22:42 +0000 Received: from VI1PR0401MB2272.eurprd04.prod.outlook.com ([fe80::91f8:d96b:f238:7962]) by VI1PR0401MB2272.eurprd04.prod.outlook.com ([fe80::91f8:d96b:f238:7962%8]) with mapi id 15.20.3564.028; Thu, 19 Nov 2020 16:22:42 +0000 From: Viorel Suman To: Mark Brown CC: "Viorel Suman (OSS)" , Liam Girdwood , Jaroslav Kysela , Takashi Iwai , Philipp Zabel , Kuninori Morimoto , "S.j. Wang" , Pierre-Louis Bossart , Peter Ujfalusi , Lee Jones , "alsa-devel@alsa-project.org" , "linux-kernel@vger.kernel.org" Subject: RE: [RFC PATCH] ASoC: ak4458: use reset control instead of reset gpio Thread-Topic: [RFC PATCH] ASoC: ak4458: use reset control instead of reset gpio Thread-Index: AQHWvGa/ULTQkQTG3EuXXoMLDy7cbKnMmESAgAAFAkCAAS01AIAB0Nww Date: Thu, 19 Nov 2020 16:22:42 +0000 Message-ID: References: <20201116222036.343635-1-viorel.suman@oss.nxp.com> <20201117173901.GH5142@sirena.org.uk> <20201118115500.GB4827@sirena.org.uk> In-Reply-To: <20201118115500.GB4827@sirena.org.uk> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=nxp.com; x-originating-ip: [5.12.106.221] x-ms-publictraffictype: Email x-ms-office365-filtering-ht: Tenant x-ms-office365-filtering-correlation-id: cbcbb8a8-0449-43b9-ddb0-08d88ca7574e x-ms-traffictypediagnostic: VI1PR0402MB3488: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:9508; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: pc0Jeef4/GH8fHcFK5TJJOTm8dgTXXee6uSpv+0Yxk1/N5fAURwnlqhaDOpFl5yS8vmPzUWRdmT/OJTGRn46hGiVblFtRtYduEzAme10kD8Mp7u4Cdv5ekoOHLfMUuXYqGN1YuMmfsvFHD63myKfLrLU5Q+ODISl4pPRg0KAfug0utN+84xX2doPBOYiElDXWMI+HeSqHIXNP2zeGNYEEhFtZGFs5uL6GwKcjOTN2gaaWIprRIilGltYIvpmH4MgmnrIAUrC63iemrzkf3kpNfaw9qqZ8gEOoqE2pW75RxRxK2OzVaNwXU/JUe6HjyUQ7bfjLB8eQ9ioElRa/mUo0Q== x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:VI1PR0401MB2272.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(396003)(346002)(376002)(136003)(366004)(39860400002)(52536014)(186003)(6916009)(5660300002)(316002)(7696005)(66476007)(66556008)(6506007)(54906003)(8936002)(66446008)(76116006)(8676002)(64756008)(66946007)(33656002)(71200400001)(7416002)(478600001)(86362001)(4326008)(44832011)(9686003)(83380400001)(26005)(2906002)(55016002);DIR:OUT;SFP:1101; x-ms-exchange-antispam-messagedata: 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 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: VI1PR0401MB2272.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: cbcbb8a8-0449-43b9-ddb0-08d88ca7574e X-MS-Exchange-CrossTenant-originalarrivaltime: 19 Nov 2020 16:22:42.3159 (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: QkwHbC6JzOGw7zTdaFXnPb6ra//b1w33aLgwd1KlIfxr/hcY+inoR6y7hXozcRSg7+4tB8pWbPfzkUiAxBd5mw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR0402MB3488 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Tue, Nov 17, 2020 at 06:17:36PM +0000, Viorel Suman wrote: > > > On Tue, Nov 17, 2020 at 12:20:36AM +0200, Viorel Suman (OSS) wrote: >=20 > > > One thing I'm not clear on is if there's some way to ensure that we > > > don't have different instances of the device resetting each other wit= hout > them noticing? > > > Shouldn't be an issue in practice for the use here. >=20 > > The way to ensure that we don't have different instances of the device > > resetting each other is to rely on the way the "shared" reset is handle= d by > reset API: > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > + ak4458->reset =3D devm_reset_control_get_optional_shared(ak4458- > >dev, NULL); > > + if (IS_ERR(ak4458->reset)) > > + return PTR_ERR(ak4458->reset); > > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D >=20 > Flip side of that then, how do we know when a reset has actually happened= ? I don't see how this can be achieved - I'd imagine some "shared" reset framework notification mechanism calling back all "listeners" in the moment the assert/deassert actually happened, there is no such mechanism currently implemented. In this specific case the GPIO purpose is to just to power on/off all codec= s. In my view with this approach it's enough to know that all codecs will be powered on the first _deassert_ call and will be powered off on the last _assert_ call. /Viorel=20