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[147.75.80.249]) by mx.google.com with ESMTPS id r10-20020a170906350a00b00a2af02c94f4si6089173eja.259.2024.01.17.13.06.16 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Jan 2024 13:06:16 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel+bounces-29445-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=Smcam5gM; arc=pass (i=1 dkim=pass dkdomain=kernel.org); spf=pass (google.com: domain of linux-kernel+bounces-29445-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) smtp.mailfrom="linux-kernel+bounces-29445-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by am.mirrors.kernel.org (Postfix) with ESMTPS id 223261F21AF3 for ; Wed, 17 Jan 2024 21:06:02 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id AF8B525561; Wed, 17 Jan 2024 21:05:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Smcam5gM" Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D14BD22EEC; Wed, 17 Jan 2024 21:05:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705525553; cv=none; b=ewbutJSQ+vMxOP+hIeCCihfvkf0dQ2xs+OqHaMV/6ko/byjfgLkILUTPNVStAb4QRpxnBlp7Usgfp/0GTzLK3KgIPUqM+Hwt9Mr6rbpeFOrgB7ZLFY+fNcg8DO2k15i6LjMeYWqEEj3BB4NzKvvg1gE6XBGR/NJY/txwJoJH83A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705525553; c=relaxed/simple; bh=6ZXHmnzWB2J471fGbFzkTEz9OgChCQqUtQGmN51eyfs=; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition: In-Reply-To; b=TukB5qsCjjxxCkqVRM634kKOc6r/DdpTqmYSwzcKyD/6gbRssm1N5wnOtpN3nvc1GlVY9YTpb8uJ+4ZaHAcp2OMB1qFgnOVoL9tSvh8jG9nLJwsexMVKIM8xObn0bsKLQMqXQPtQDNYRHGx9u/uaOcVxhkotzdcQlID55ZPR59U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Smcam5gM; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id C022EC433F1; Wed, 17 Jan 2024 21:05:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1705525553; bh=6ZXHmnzWB2J471fGbFzkTEz9OgChCQqUtQGmN51eyfs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Smcam5gMJPERHyHvTLRciyWk2aWC9EB/6WSgHFGVLOsYSky95RmvaoRWMG6MP0pPJ vwI1zCRp60xbntgVKLCtJMLWZ7nDCOTw2Q55xgP/vivALdAWE/GfkbkqE9vQaA76Ik kd3PruvwTw5OEeNmFmTi3E7ahakOmbw0IQBFb4F/0eIfhaPeMnJCZdrJAXIt/VOEc2 qJYf0LI2tKxTmYmUp9KKToWuXHZqBjq1K2vktTY0tyEK69Tp5NLa/cZz4X+6pzulQw nwZ8dq+WHa8FAKmivGmoWa/YQ1nv80ZZn+lfgNRJANM5uiTYUanS5OyVK2bD4tpYCO aWZNNZa9UwYTw== Date: Wed, 17 Jan 2024 22:05:47 +0100 From: Andi Shyti To: "Boddu, Sai Pavan" Cc: "linux-kernel@vger.kernel.org" , "linux-i2c@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "Simek, Michal" , Lars-Peter Clausen , Wolfram Sang Subject: Re: [PATCH] i2c: cadence: Avoid fifo clear after start Message-ID: References: <20240105125258.2470397-1-sai.pavan.boddu@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hi, > >> b/drivers/i2c/busses/i2c-cadence.c > >> index de3f58b60dce..6f7d753a8197 100644 > >> --- a/drivers/i2c/busses/i2c-cadence.c > >> +++ b/drivers/i2c/busses/i2c-cadence.c > >> @@ -633,6 +633,7 @@ static void cdns_i2c_mrecv(struct cdns_i2c *id) > >> > >> if (hold_clear) { > >> ctrl_reg &= ~CDNS_I2C_CR_HOLD; > >> + ctrl_reg &= ~CDNS_I2C_CR_CLR_FIFO; > > > >I'm wondering whether the whole ctrl_reg should be reset after the first write. > [Boddu, Sai Pavan] previous implementation of read-modify-write was good then ? I don't know, I'm just asking... because rather than read-modify-write, this is read-modify-write-modify-write :-) I'm just wondering if after the first write ctrl_reg is still holding a valid value. Andi