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[23.128.96.18]) by mx.google.com with ESMTP id ot8si699991pjb.1.2022.01.24.15.17.41; Mon, 24 Jan 2022 15:17:53 -0800 (PST) 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=@kernel.org header.s=k20201202 header.b=jq28KEBd; 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; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1844844AbiAXXK3 (ORCPT + 99 others); Mon, 24 Jan 2022 18:10:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1581269AbiAXWRS (ORCPT ); Mon, 24 Jan 2022 17:17:18 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 40EA3C04A2D5 for ; Mon, 24 Jan 2022 12:45:39 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AD49EB8121C for ; Mon, 24 Jan 2022 20:45:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 677CEC340E5; Mon, 24 Jan 2022 20:45:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643057136; bh=yrceQicqpEIe7QLu9/qr6uF5VLg1Sq98e0P9UJLrRlQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jq28KEBd4ggLqKrCYV3myDJMtlj5L7GOiePTyMeAN4LQ2qizDarBE+TpI4EMAJEeh VEfNL3meHpQRJfSfyfgVma9C32VAFCg8cXa04NWUBa1jLzP5yYcPRy4otsZ35qv6+1 n5d6b8ru44U0QPQ7YIN+o8RYbcZV8l0qwYK7yk4ORKS6jNSh+ifNp2fnhozI5UFmO4 +1T2vBbZ+cCjX3xwOj7xVerW6b7luhj3DDVinXfglQRDxTwdYWCjn1faov30g/Ggwv ryzdBjFbDFVOCD2RUhchR8wL2eH+u1LhkDjHmHS2VVXSVYiiTatHXPMFB4mABn/rm/ HBaPjyxQg14YQ== Date: Mon, 24 Jan 2022 20:45:32 +0000 From: Mark Brown To: Detlev Casanova Cc: linux-kernel@vger.kernel.org, Dave Stevenson , Liam Girdwood Subject: Re: [PATCH v2 8/9] regulator/rpi-panel-attiny: Don't read the LCD power status Message-ID: References: <20220121152056.2044551-1-detlev.casanova@collabora.com> <20220121152056.2044551-9-detlev.casanova@collabora.com> <5533342.DvuYhMxLoT@falcon9> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="STjVNrkqRnBsFO5k" Content-Disposition: inline In-Reply-To: <5533342.DvuYhMxLoT@falcon9> X-Cookie: The second best policy is dishonesty. Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --STjVNrkqRnBsFO5k Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jan 24, 2022 at 03:22:35PM -0500, Detlev Casanova wrote: > On Friday, January 21, 2022 11:30:39 A.M. EST Mark Brown wrote: > > If that's the case since you're using regmap would it not make sense to > > enable caching in order to minimise reads in general. > Would caching avoid all reads if the values are written at least once bef= ore?=20 > The idea here is to make sure they are never read, I'm not sure if the re= gmap=20 > cache ensures no read in this situation. 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