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 E2861C77B61 for ; Tue, 28 Mar 2023 14:36:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233066AbjC1OgE (ORCPT ); Tue, 28 Mar 2023 10:36:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52006 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233204AbjC1Ofw (ORCPT ); Tue, 28 Mar 2023 10:35:52 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE7EDCDED; Tue, 28 Mar 2023 07:35:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1680014129; x=1711550129; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=PwPPDuu5LzPD0qVFdDs/5snLEgHkaAUrZcOrnpL6Ij4=; b=VKEtnEyDsHtl3JrEYTWyZNIMiThqndMOUWO0U0VcdFe/mhCwUZ6q6XIa pb37om0y+nsqpo4or3poIPgHHwefJRze1LZiZGxO7cCfC1+EZ4b0NJqVW ZCYUkOmcWlLdlwddBmcv0kAWCfsgN6uGjj2eKEyTAkPdS99QNcaMIOxMP Ukcf6zwJAe26n6z19jkYzIUW53SGf06d0TXcmIoeqoK6Jn/3gNKQD//VD D/S6KmLdFXmkrYqIVsxIx31+Y8ibCwdlcNtlHlJd8f+4IfJcymhw9Igvn EP+oCawT385aAl0EbSqh0yLUULLo1bQGPMfT1+PWNEVGSyuIkGxm/KrLl w==; X-IronPort-AV: E=McAfee;i="6600,9927,10662"; a="405517670" X-IronPort-AV: E=Sophos;i="5.98,297,1673942400"; d="scan'208";a="405517670" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Mar 2023 07:35:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10662"; a="683923841" X-IronPort-AV: E=Sophos;i="5.98,297,1673942400"; d="scan'208";a="683923841" Received: from smile.fi.intel.com ([10.237.72.54]) by orsmga002.jf.intel.com with ESMTP; 28 Mar 2023 07:35:22 -0700 Received: from andy by smile.fi.intel.com with local (Exim 4.96) (envelope-from ) id 1phAPv-009f4E-1f; Tue, 28 Mar 2023 17:35:19 +0300 Date: Tue, 28 Mar 2023 17:35:19 +0300 From: Andy Shevchenko To: Nuno =?iso-8859-1?Q?S=E1?= Cc: Mark Brown , "Sahin, Okan" , Lee Jones , Rob Herring , Krzysztof Kozlowski , Liam Girdwood , Jonathan Cameron , Lars-Peter Clausen , Cosmin Tanislav , Stephen Boyd , Caleb Connolly , Lad Prabhakar , "Bolboaca, Ramona" , ChiYuan Huang , "Tilki, Ibrahim" , William Breathitt Gray , Arnd Bergmann , ChiaEn Wu , Haibo Chen , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-iio@vger.kernel.org" Subject: Re: [PATCH v6 5/5] mfd: max77541: Add ADI MAX77541/MAX77540 PMIC Support Message-ID: References: <20230307112835.81886-1-okan.sahin@analog.com> <20230307112835.81886-6-okan.sahin@analog.com> <20230315175223.GI9667@google.com> <20230315175257.GJ9667@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 28, 2023 at 04:18:30PM +0200, Nuno Sá wrote: > On Tue, 2023-03-28 at 14:46 +0100, Mark Brown wrote: > > On Tue, Mar 28, 2023 at 03:26:44PM +0200, Nuno Sá wrote: > > > > > IIRC, regmap_read() is not really reentrant and it is used in the > > > IIO > > > driver on the sysfs interface. So, yeah, I think you need the > > > regmap > > > lock and better just leave the config as is. Yes, the lock is opt- > > > out > > > so let's not disable it :) > > > > All the regmap operations are fully thread safe. > > Even if 'config->disable_locking' is set? I think that is what's being > discussed in here... In case the driver has its own lock to serialize IO how on earth the regmap lock is needed. That's what I asked the author of the driver. He told the code doesn't require the regmap lock, and I tend to believe the author. So, why to keep it? -- With Best Regards, Andy Shevchenko