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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A4245C433F5 for ; Tue, 4 Sep 2018 16:11:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A38020645 for ; Tue, 4 Sep 2018 16:11:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6A38020645 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=the-dreams.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727726AbeIDUhF (ORCPT ); Tue, 4 Sep 2018 16:37:05 -0400 Received: from sauhun.de ([88.99.104.3]:60424 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727272AbeIDUhF (ORCPT ); Tue, 4 Sep 2018 16:37:05 -0400 Received: from localhost (i577B9DB6.versanet.de [87.123.157.182]) by pokefinder.org (Postfix) with ESMTPSA id E80212C0114; Tue, 4 Sep 2018 18:11:15 +0200 (CEST) Date: Tue, 4 Sep 2018 18:11:14 +0200 From: Wolfram Sang To: shubhrajyoti.datta@gmail.com Cc: linux-i2c@vger.kernel.org, michal.simek@xilinx.com, linux-kernel@vger.kernel.org, Shubhrajyoti Datta Subject: Re: [PATCH] i2c: xiic: Make the start and the byte count write atomic Message-ID: <20180904161114.GC5000@kunai> References: <1535967671-7784-1-git-send-email-shubhrajyoti.datta@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="wxDdMuZNg1r63Hyj" Content-Disposition: inline In-Reply-To: <1535967671-7784-1-git-send-email-shubhrajyoti.datta@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --wxDdMuZNg1r63Hyj Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 03, 2018 at 03:11:11PM +0530, shubhrajyoti.datta@gmail.com wrot= e: > From: Shubhrajyoti Datta >=20 > Disable interrupts while configuring the transfer and enable them back. >=20 > We have below as the programming sequence > 1. start and slave address > 2. byte count and stop >=20 > In some customer platform there was a lot of interrupts between 1 and 2 > and after slave address (around 7 clock cyles) if 2 is not executed > then the transaction is nacked. >=20 > To fix this case make the 2 writes atomic. >=20 > Signed-off-by: Shubhrajyoti Datta > Signed-off-by: Michal Simek I assume simply changing the order of the register writes won't fix it? I also assume this is stable material? --wxDdMuZNg1r63Hyj Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAluOrqIACgkQFA3kzBSg KbapRxAArZeq002KSZpUYsWhatVQEjnYvYcwpQBRDx5hECYdi+eA6jEfmMirD0+Z sU0SrQGu4DZ0pTGcB7Jcz68hIiL6E6o9+BBwI/23A/K+IanWMv/5YeDafBkZJpEu VXvcXcMB9YuOEl00Oz/kUz4IPDeL2Rs9cCeQFAIU+l8MPGvNTel1/h1r9Q04O6/k Bsd4g279d4QueTO+n6UhQYu3ny9d9j5VAF5S1aO/RZqlt29blZ1UX5RTxW3Hii1C kOdTVlZknnPD1//4SKC02W403AiVAaieitCZ2COvpoomwQSkluSEIdmohk146ssO TTTR+OmNx/bAaMgDYZWasRB+uui6gw2X9ELrermwF/VLWv8ok4zUc/AqAlnpxJgC 7exqwyXN9SFvETSs77w5PgCmnvMW2inkiS+exKcnYzg/b/vW+PvyALB7M7A23Z9D Rmo4U6zI4cdsffbe9DuuOheBYTfndPrMEWjVrxbpjGygGb5ZvXY3ym6yOUDqrYah swFRaHVrn7U7oJE42ve6efrvjhN3yWRaqKH4si9csNWQa4msw+LvRABj7kznFraX xMFNXzSquz7ZwJ+yZeMomzlbITIhXIlZeQAJe1vNiIGP2zOowpI1t+xTvJsKJqPS G+wxa8LNrC99WGL3nV68ajT58GhalGNzu+gsk394zov8ywxrMMg= =YYMd -----END PGP SIGNATURE----- --wxDdMuZNg1r63Hyj--