Received: by 2002:a05:6a10:206:0:0:0:0 with SMTP id 6csp3350015pxj; Tue, 1 Jun 2021 03:20:13 -0700 (PDT) X-Google-Smtp-Source: ABdhPJx0G2v14NDvG83eiK4Gt1saM4aVU71vfBis+rSdGFZDfr8uDO4lsSsqmY1KiDCGlx19Z/Sw X-Received: by 2002:a17:907:20c6:: with SMTP id qq6mr487521ejb.207.1622542813700; Tue, 01 Jun 2021 03:20:13 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1622542813; cv=none; d=google.com; s=arc-20160816; b=xDq34qorwl4BfG6N/wZT3QVxHq8w9EClreLAMeooheODumEQ3Qag9RbHK4//whPcwV y0ELSBRQ56UBumAxbxROPzC2aI9AU9ScSXfEsYWACtuVs8EavvtLI3fs1RmuO4WOiLAG tOp/BEQaOjrs9nw28bIt0LyT2QdRr5KgIZSfdwIM/f4UJVyR/elcUh+6nicozkOc1fub UsMSo0GoLp4oOXa8kUQO6Vj9FJG0C0iWVjBFiRMWO4vsOUiy556vnGTBq9hbqTqQQtKf rWBV6pK7QcM5rU761GvzgOUD7XJIFm85i5u0obbASCZRItBKXAA7OG1Oq8CJjBFfMedC uf3w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:message-id:user-agent:references:in-reply-to :subject:cc:to:from:date:content-transfer-encoding:mime-version :dkim-signature; bh=HzIP1Z1xTd2WYU6MG28q+U1UuISttybt2KJCWFWdwxw=; b=J7xoJe/pxxMoDJwilKco65z3Zzw951YIHK+AC3ub25FfQnVzffXBOlYIDcqj009kDr bKu6cC9CbDmyJl2qy5puWQZZ/dWi4d17vyEITlXSPr5VO/4VfJ9RDgbyaP8thEL74rmB DMSLhBBMY/+Jf8tP9zA84G7tW8IaWFEpZ+4hYeOpgZJhA2CSZnL3I3DhBUXcxRnRPJR5 nViYvpdbiI1NZED40Z5K+y9TtzB3SPnpKKFgMjR33SfVIojmqRMrDFHhY8BRSNUKxNOx 9biuyVHc/7EWUQXZYC0IlfAmF54psLh6OJI9rHwcIgNYy/alsxsRfv97eC4eb6N2tJle QzpA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@walle.cc header.s=mail2016061301 header.b=ikvzPSPB; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id y21si6082203ejb.616.2021.06.01.03.19.50; Tue, 01 Jun 2021 03:20:13 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@walle.cc header.s=mail2016061301 header.b=ikvzPSPB; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232546AbhFAKUZ (ORCPT + 99 others); Tue, 1 Jun 2021 06:20:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229538AbhFAKUY (ORCPT ); Tue, 1 Jun 2021 06:20:24 -0400 Received: from ssl.serverraum.org (ssl.serverraum.org [IPv6:2a01:4f8:151:8464::1:2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4CA78C061574; Tue, 1 Jun 2021 03:18:43 -0700 (PDT) Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 8759222236; Tue, 1 Jun 2021 12:18:39 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1622542720; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=HzIP1Z1xTd2WYU6MG28q+U1UuISttybt2KJCWFWdwxw=; b=ikvzPSPBKKIxeop7dDEupVKswEojvHqdVIaaBgq9zIttdbd0AxrcVhK7IQjaziflagzzR+ hsOwb6huI9MI/NTR6PJL13VijS38vOkSHKf9+DTGq4z2O0/LW0cl6CmAIQKfSx05cA9pVC t9oZ4jkZkJ7+jp3ETR1Y7cLEL8IddqA= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 01 Jun 2021 12:18:39 +0200 From: Michael Walle To: Linus Walleij Cc: Andy Shevchenko , Hans de Goede , Sander Vanheule , Andrew Lunn , Pavel Machek , Rob Herring , Lee Jones , Mark Brown , Greg Kroah-Hartman , "Rafael J . Wysocki" , Bartosz Golaszewski , Linux LED Subsystem , devicetree , "open list:GPIO SUBSYSTEM" , Linux Kernel Mailing List Subject: Re: [PATCH v3 0/6] RTL8231 GPIO expander support In-Reply-To: References: <02bbf73ea8a14119247f07a677993aad2f45b088.camel@svanheule.net> <84352c93f27d7c8b7afea54f3932020e9cd97d02.camel@svanheule.net> User-Agent: Roundcube Webmail/1.4.11 Message-ID: X-Sender: michael@walle.cc Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 2021-06-01 11:59, schrieb Linus Walleij: > Just regarding all registers/memory cells in a register page > as default volatile (which is what we do a lot of the time) > has its upsides: bugs like this doesn't happen. I don't think this is the bug here. If it is really a write-only register the problem is the read in RMW. Because reading the register will return the input value instead of the (previously written) output value. -michael