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 alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 98368C7EE2C for ; Sat, 27 May 2023 10:42:18 +0000 (UTC) Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 797BD820; Sat, 27 May 2023 12:41:26 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 797BD820 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1685184136; bh=3ENny4TLjAP6BGM/oHhGNzefJxUwL+iQcwwURQ1DS0E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-Id: List-Archive:List-Help:List-Owner:List-Post:List-Subscribe: List-Unsubscribe:From; b=A26g5F6k6IGeotm5P5cVEu24KZT75E1chAQjoD7eaR7vvgEC7QuVQw7+p1911aUl8 ZRgWI3KdNYg5X4zAayKhcns+wVDV+b7r3vtfEpuJL4B8nrAiBkasDGAnvMFB9p495B fSd2LhI8dO/Eo6T4UTAEIn1AHYPOqv9Jd/68k6JM= Received: by alsa1.perex.cz (Postfix, from userid 50401) id 0C54AF80552; Sat, 27 May 2023 12:40:37 +0200 (CEST) Received: from mailman-core.alsa-project.org (mailman-core.alsa-project.org [10.254.200.10]) by alsa1.perex.cz (Postfix) with ESMTP id 7C9CCF80552; Sat, 27 May 2023 12:40:37 +0200 (CEST) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 1FD21F80549; Sat, 27 May 2023 12:39:06 +0200 (CEST) Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 771E4F80544 for ; Sat, 27 May 2023 12:39:01 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 771E4F80544 Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=jPqBWun2 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 D5DD360BC8; 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> Message-ID-Hash: CIR5PPI4O7NBBOX2GA7WCI5YXFMD4TR6 X-Message-ID-Hash: CIR5PPI4O7NBBOX2GA7WCI5YXFMD4TR6 X-MailFrom: vkoul@kernel.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-alsa-devel.alsa-project.org-0; header-match-alsa-devel.alsa-project.org-1; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.8 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: 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