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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 2A808C3A5A9 for ; Wed, 4 Sep 2019 21:37:55 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EEAEB20674 for ; Wed, 4 Sep 2019 21:37:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Ck10/4Cl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EEAEB20674 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-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type:Cc: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=6jzd7H1x/MMgg/WwYjzFTf22EkyO6ZN9e6j1gozXr04=; b=Ck10/4Cl2RTeUvXIMdn94o2Qh T1UewfqG6QBzaLgHeYszZueG6sSgw3ga8dRwMepZn6E8TcE2P+0GugSeOuJaKeYaCkchDj3G1mrp/ ra7XfyoLWcFA24aKjK7zifjvR5IbclAJRKzxASyCOVJrWpqZ5sQ4pr3JLYulBLnmlme+I27gr+ZI6 A/+K77I2hxIItmrZ66kURO3E6Pb2TFFy1KSu9u7Kb4+G7w5yrawjiFpp3FNHJW4TtVDt9azyxrfwE 2xq8IQpORIplzMX+9e8WSx4yzqlTErT+QTOvIJXaz2ySJeSz9XQPMJw6jfaMbWqs/8danJGYOd5XD AwxOokzXA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i5cyP-0007me-4p; Wed, 04 Sep 2019 21:37:53 +0000 Received: from sauhun.de ([88.99.104.3] helo=pokefinder.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i5cyI-0007mI-O5 for linux-arm-kernel@lists.infradead.org; Wed, 04 Sep 2019 21:37:48 +0000 Received: from localhost (p54B337F1.dip0.t-ipconnect.de [84.179.55.241]) by pokefinder.org (Postfix) with ESMTPSA id E8DCE2C08C3; Wed, 4 Sep 2019 23:37:45 +0200 (CEST) Date: Wed, 4 Sep 2019 23:37:45 +0200 From: Wolfram Sang To: Ray Jui Subject: Re: [PATCH v1 1/1] i2c: iproc: Add i2c repeated start capability Message-ID: <20190904213745.GG23608@ninjato> References: <1565150941-27297-1-git-send-email-rayagonda.kokatanur@broadcom.com> <20190830125626.GC2870@ninjato> <3e70fa7e-de13-4edd-2e17-b7c56e91d220@broadcom.com> <20190831094940.GA1138@kunai> <540c4e2d-0dd5-5260-30b2-e1589b279d71@broadcom.com> MIME-Version: 1.0 In-Reply-To: <540c4e2d-0dd5-5260-30b2-e1589b279d71@broadcom.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190904_143746_929185_DD5641AA X-CRM114-Status: GOOD ( 11.63 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, Lori Hikichi , Florian Fainelli , Shivaraj Shetty , Rayagonda Kokatanur , linux-kernel@vger.kernel.org, Icarus Chau , Rob Herring , bcm-kernel-feedback-list@broadcom.com, linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org Content-Type: multipart/mixed; boundary="===============2115852290790848561==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============2115852290790848561== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="EDJsL2R9iCFAt7IV" Content-Disposition: inline --EDJsL2R9iCFAt7IV Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > I think you are right that the controller does not seem to support > additional I2C features in addition to SMBUS. >=20 > However, my concern of switching to the smbus_xfer API is: >=20 > 1) Some customers might have used I2C_RDWR based API from i2cdev. Changing > from master_xfer to smbus_xfer may break the existing applications that a= re > already developed. Well, given that you add new quirks in the original patch here, you are kind of breaking it already. Most transfers which are not SMBus-alike transfers would now be rejected. For SMBus-alike transfers which are sent via I2C_RDWR (which is ugly), I have to think about it. > 2) The sound subsystem I2C regmap based implementation seems to be using > i2c_ based API instead of smbus_ based API. Does this mean this will also > break most of the audio codec drivers with I2C regmap API based usage? I don't think so. If you check regmap_get_i2c_bus() then it checks the adapter functionality and chooses the best transfer option then. I may be missing something but I would wonder if the sound system does something special and different. --EDJsL2R9iCFAt7IV Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAl1wLqkACgkQFA3kzBSg KbbdPBAAsHYbJFSjXbArIzGj/6rYqzbUnvYeKqVHK/C1E7C1/89RAeVkba81NFsu PjHeTsrPaMQ6lK5Df79WK8I0EDf++K1Imv1edG64CamFTHqc60rVShO3ifPnQf8P XrOEAUxLEsoXjAqsUy9Nl2xU9roZxcglRdSSg+rlDsN6WRJ8bq0xg7I/7pPs0t/m DU+77rOjrqcj3mKJsMvcH/ay4tAYQGwXKalqLwkRuy6u5bQ98G/z9mPdGRwBXxx7 2lg61m1t05rmuU8PQZnnD1xB8syyt3/ivq4VWVs/9ghtAoTirMGtkhWu0SIQ17M5 KePWtCxia4A4rHQeEF6vdrbuZAcPqFy8ttnoccsUBBXLy4KYs2zguxiss0EXq95t QHW83RzcyxpPqqbVPAgtoQONVcFBLvJ3p5LDIHi/kgosLcTyyjTfre1vzRcG8j9S j/q++XaORKmfJ4evfK5AdbexTLnXGlUyXcRj0vQElOHxVOwk2PbjYAAq58XKsY9W 95LmlBMR2kDB/GCdZWGdTt29hyyhLgde4temx2eBCAqafAhAsPdFp8sFA2mEkaC4 h5rby01u7yD66c8hpI/4q5psgoj1j7fRctKsdtxb/S8P2sHcKZ6HygntSmmEb+WG BGd+gabtDbQBSHrOxqYrYBZVQFNf3YABNMFvC5LuvgMs3Ek59iM= =s2Lx -----END PGP SIGNATURE----- --EDJsL2R9iCFAt7IV-- --===============2115852290790848561== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============2115852290790848561==--