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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 E07B2C433FF for ; Tue, 30 Jul 2019 15:51:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7455204FD for ; Tue, 30 Jul 2019 15:51:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564501916; bh=Satq2eEMXIbB0aB+E4vC0WoAtw8SMBMHI0WXpWtRuYs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=TOjnQcb/QejF3KAf84imXVKDQNtVBijHyWfWq3SPQ7uZVbh0KlGXeSB/EJ22FB3Nb pOyh7JqjWiCPLlm35mnNRVQsthCchqZjxf+lQ7uSZgtX8i1JatDdnaBWe8dVa84e3j UhqHGFystRSsQWY73K44Ok23BvcroxYQ4XMQe9NY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732674AbfG3Pvz (ORCPT ); Tue, 30 Jul 2019 11:51:55 -0400 Received: from heliosphere.sirena.org.uk ([172.104.155.198]:58752 "EHLO heliosphere.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725974AbfG3Pvz (ORCPT ); Tue, 30 Jul 2019 11:51:55 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sirena.org.uk; s=20170815-heliosphere; h=In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=Satq2eEMXIbB0aB+E4vC0WoAtw8SMBMHI0WXpWtRuYs=; b=J1ZC52QIsMjMi5k2i2Fvr0+nV AuizVSMIB5ohxsLuqMXvxPDnGN3s7Ru76VojFpPcd5fQqygq3HMaOXKDD0VEBrs7Btv2YSwqH73rL 2gC9VPKgK6bIMpJY5oFm8wW8bzuPYLpVtZ+MBg74aqkS+Q2G++Vy42i1p1GAoxDhc9XAc=; Received: from cpc102320-sgyl38-2-0-cust46.18-2.cable.virginm.net ([82.37.168.47] helo=ypsilon.sirena.org.uk) by heliosphere.sirena.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1hsUOT-0007rr-3R; Tue, 30 Jul 2019 15:50:29 +0000 Received: by ypsilon.sirena.org.uk (Postfix, from userid 1000) id E52FC2742CB5; Tue, 30 Jul 2019 16:50:27 +0100 (BST) Date: Tue, 30 Jul 2019 16:50:27 +0100 From: Mark Brown To: Thomas Preston Cc: Mark Rutland , devicetree@vger.kernel.org, alsa-devel@alsa-project.org, Charles Keepax , Kuninori Morimoto , Kirill Marinushkin , Cheng-Yi Chiang , Marco Felsch , Takashi Iwai , Annaliese McDermond , Liam Girdwood , Paul Cercueil , Vinod Koul , Rob Herring , Srinivas Kandagatla , linux-kernel@vger.kernel.org, Jerome Brunet Subject: Re: [alsa-devel] [PATCH v2 3/3] ASoC: TDA7802: Add turn-on diagnostic routine Message-ID: <20190730155027.GJ4264@sirena.org.uk> References: <20190730120937.16271-1-thomas.preston@codethink.co.uk> <20190730120937.16271-4-thomas.preston@codethink.co.uk> <20190730141935.GF4264@sirena.org.uk> <45156592-a90f-b4f8-4d30-9631c03f1280@codethink.co.uk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="DesjdUuHQDwS2t4N" Content-Disposition: inline In-Reply-To: <45156592-a90f-b4f8-4d30-9631c03f1280@codethink.co.uk> X-Cookie: Times approximate. User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --DesjdUuHQDwS2t4N Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jul 30, 2019 at 04:25:56PM +0100, Thomas Preston wrote: > On 30/07/2019 15:19, Mark Brown wrote: > > It is unclear what this mutex usefully protects, it only gets taken when > > writing to the debugfs file to trigger this diagnostic mode but doesn't > > do anything to control interactions with any other code path in the > > driver. > If another process reads the debugfs node "diagnostic" while the turn-on= =20 > diagnostic mode is running, this mutex prevents the second process > restarting the diagnostics. > This is redundant if debugfs reads are atomic, but I don't think they are. Like I say it's not just debugfs though, there's the standard driver interface too. --DesjdUuHQDwS2t4N Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl1AZ0MACgkQJNaLcl1U h9A+KQgAgi4HkmsbIandzuTrFA6N2E9Zrc7WMisuFB9GE/OnLiU559yFfrABha81 2AJ4vwv4WOwP6Cl48kFT7W90WgsJljB6F0d/SaiwvhNmwf2ifUVANo+tkNv8L2kn W/7p0/OQ1tuFhU9OI98e1YbqSI/TEcgQx3CEp0diUdcmv1C55X6cn1tjj5Mn0+hz Mf2IV9Q1KMJQBeHqm6PvdWjzxbnQ7iUEPQ6SoP6PwTjEvpWN/+Cv7q/wo1FCs1hb 1nYLoWrVYhOaQyzAxxJ/S2bRl5TybnmgSJOpj1ZNMRcHdED93sk3GMNSqqAOD68L nQQV16tM/EvyPsbQE+AMJFrAKfZLdg== =H0id -----END PGP SIGNATURE----- --DesjdUuHQDwS2t4N--