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 1AD7ACCA47F for ; Tue, 19 Jul 2022 12:10:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238486AbiGSMKY (ORCPT ); Tue, 19 Jul 2022 08:10:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51682 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238393AbiGSMIx (ORCPT ); Tue, 19 Jul 2022 08:08:53 -0400 Received: from mail-lj1-x231.google.com (mail-lj1-x231.google.com [IPv6:2a00:1450:4864:20::231]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5943250056 for ; Tue, 19 Jul 2022 05:01:57 -0700 (PDT) Received: by mail-lj1-x231.google.com with SMTP id q7so17064144lji.12 for ; Tue, 19 Jul 2022 05:01:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=13/NnKJpd70PTMK9kZ5dgVlJtFfN05EcbVDMd8GoMwc=; b=AQB/kKBsayBytIdgmCx2efH5Juv9bq4q7qm5bzTtUfE6puwvo1ohA1wNqzdlF8r66J a/8WpcwcCf/N2Dyk6nVGYeVkEI2BaZ0tYaznmGII5dugznQumSh2cGUvmI0gNJySbBi5 4RK+LgQFVUlr55QBFLaMxRS6OgaFP+ENi9EEa25I/baHPw/zh3ajHKYfkdatxBipzRiH QfLOjPMXD7TFk35Hd/4frr0Bt97egyT+HXsIyE1yghotyOKnuDlXN8vgWWx6+youUhIM 3ym5iXakYlwBuIvvb+mI91bHTvg+8NIpncyz2KUH2LTG97FdmgruBl8lgGp/93AeTj/3 H9Qw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=13/NnKJpd70PTMK9kZ5dgVlJtFfN05EcbVDMd8GoMwc=; b=O87p7GLHyyGtFpIRbBpPjhh7hdpuNYMyonHALZhceY1rjkGOLWrA55lj1NeGsXX27t Iwx3VbSivVkIZKu7uHM0Nf7Ts8xrOBpwD5zLCQDzULnFn58JpYa2IPSm55oVmwJu5LYW 745NhN7WBnbKKVZZd6l1w6+kN8NvNVztverEaLkUaBWtweQfqjATN9u9Zmly74ngvBfN XXlXRB/MSnthqQ9/5t7NpmWJHPaT2EjzcO6XeE14/VIzD5ZgUpVaLB/QOWs3LL4EbIZ9 kjWVF+t3fkeid4HpOPh85HGjWkMDeo1A7cbDEY7Ix63M8D+j89rgfZPcQrEi3Y0xGuxL cMQg== X-Gm-Message-State: AJIora9FTHp/UOXRNHqoucOiK1qfBClzIxsAAulm45xwkFjBl317sisd oggtUfyjHlIHyXGKZvV9mA8PKA== X-Google-Smtp-Source: AGRyM1vuiI5amreRlAA+TpAg7fM7AHTqjdGNjhtrNKbV4bs1XaM+u0ph9q8O+RdiGl58rkIUZAaIOg== X-Received: by 2002:a2e:9849:0:b0:25d:63f7:ce3b with SMTP id e9-20020a2e9849000000b0025d63f7ce3bmr14095035ljj.427.1658232115658; Tue, 19 Jul 2022 05:01:55 -0700 (PDT) Received: from [192.168.115.193] (89-162-31-138.fiber.signal.no. [89.162.31.138]) by smtp.gmail.com with ESMTPSA id u14-20020a19790e000000b0047fab4c3651sm3180289lfc.85.2022.07.19.05.01.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 19 Jul 2022 05:01:54 -0700 (PDT) Message-ID: <3ac8f0cb-492e-968e-1b74-ead3e40478e3@linaro.org> Date: Tue, 19 Jul 2022 14:01:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: Question: regmap_field_write() - why using update? Content-Language: en-US To: Mark Brown Cc: Srinivas Kandagatla , Linux Kernel Mailing List References: <14b0e150-511c-867a-281a-1d13e7e318e8@linaro.org> <277e0484-60bd-7405-4cd1-acf0a03ef195@linaro.org> From: Krzysztof Kozlowski In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14/07/2022 20:27, Mark Brown wrote: > The write only registers are a good point - we could handle them through > special casing, that'd avoid any overhead from reading or issues if a > physical read happens to return something unfortunate for some reason. I have something ready and I will send it soon. > Now I think about it there's also the fun case of registers which don't > have symmetric read and write, though at some point regmap_field does > stop being useful and those might well be pushing it. Right. Best regards, Krzysztof