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 C08E1C77B7E for ; Sat, 27 May 2023 10:39:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232321AbjE0KjE (ORCPT ); Sat, 27 May 2023 06:39:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231608AbjE0KjB (ORCPT ); Sat, 27 May 2023 06:39:01 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4BD78D8 for ; Sat, 27 May 2023 03:39:00 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id D5B5560B67 for ; Sat, 27 May 2023 10:38:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AD647C433D2; Sat, 27 May 2023 10:38:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685183939; bh=3ENny4TLjAP6BGM/oHhGNzefJxUwL+iQcwwURQ1DS0E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jPqBWun2jt1uDOsPLMUyWY1ve5naJCAfB7AwNdGcZ30zRQ5zxCpPRUG1N0e2UwusN d1nms3MgE83xe42z+IhTSmHgdKmh6AG7MgZnne3AhmJtpfvaFOa3XpmZypEzVVVB/b 1e7js1lGGCmUN/9dRMLzaTpHdaVsF1kLAFFnbfhbGRpaXVLA+n0Tf6Fhdsa4Lf427D 16K4N+WYt3x6VIZK+HdRCs4A74WjMgwyAtXGY/xAdjhpVl5aGqqC60UcpweiN18kZq nTA7HZLDFw69frvGso96Jw/ACc6Orw4RtA0pFR0rK8CtN7UX9BzQDJ1ENj8MHf2T4U K7DZpuE2PQxLg== Date: Sat, 27 May 2023 16:08:55 +0530 From: Vinod Koul To: Bard Liao Cc: alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, pierre-louis.bossart@linux.intel.com, bard.liao@intel.com Subject: Re: [PATCH] soundwire: intel: read AC timing control register before updating it Message-ID: References: <20230515081301.12921-1-yung-chuan.liao@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230515081301.12921-1-yung-chuan.liao@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 15-05-23, 16:13, Bard Liao wrote: > From: Chao Song > > Start from ACE1.x, DOAISE is added to AC timing control > register bit 5, it combines with DOAIS to get effective > timing, and has the default value 1. > > The current code fills DOAIS, DACTQE and DODS bits to a > variable initialized to zero, and updates the variable > to AC timing control register. With this operation, We > change DOAISE to 0, and force a much more aggressive > timing. The timing is even unable to form a working > waveform on SDA pin on Meteorlake. > > This patch uses read-modify-write operation for the AC > timing control register access, thus makes sure those > bits not supposed and intended to change are not touched. Applied, thanks -- ~Vinod