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=-3.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_NEOMUTT 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 05A53C43381 for ; Tue, 12 Mar 2019 15:45:14 +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 C921120693 for ; Tue, 12 Mar 2019 15:45:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="jFUQ/xrt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C921120693 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=croE/EMYT+rPkKesGgyfQNG4igNXbj6HvAF0tuLNHpE=; b=jFUQ/xrt0Zny5aiDvdfq2+4Db AkJDghrvAp0rPtL7F1gSF0QwskSfwLbrwZ8KZv/nrH98skz5oAzvcWWPqLM2xq6GzQeb05LfCCVQW kqt5z0/nyKz9wPmAX1ZH7GfCS+5RlS8XOtFKZcvfuCtEvZzbTRKg3blJYpo4r6cwCjWOxSt5VS/VX 4TQm6VjTIUQ7YQvODue43SpaV+gKU+rmbl8McIrrSra2pbexrKoYSAMUI+PYfzvngH71sBXLzDq0H 5axII2ICk3xj/pRC+kSTSbpsH3RkaJDUbeKFMFGB6dKrNsfZaLlYOB1b0JZ56vbw9wEVWsLpmwlms k0JMvH88g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h3jaU-0006Xm-QY; Tue, 12 Mar 2019 15:45:06 +0000 Received: from sauhun.de ([88.99.104.3] helo=pokefinder.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h3jaQ-0005s1-OT for linux-arm-kernel@lists.infradead.org; Tue, 12 Mar 2019 15:45:04 +0000 Received: from localhost (p54B335FE.dip0.t-ipconnect.de [84.179.53.254]) by pokefinder.org (Postfix) with ESMTPSA id A876C2C282F; Tue, 12 Mar 2019 16:45:01 +0100 (CET) Date: Tue, 12 Mar 2019 16:45:01 +0100 From: Wolfram Sang To: Andy Shevchenko Subject: Re: [RFC PATCH v2 0/7] i2c: core: introduce atomic transfers Message-ID: <20190312154501.6v2symbq6eutp6dj@ninjato> References: <20190302134735.4393-1-wsa+renesas@sang-engineering.com> MIME-Version: 1.0 In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190312_084502_954795_86DD40F5 X-CRM114-Status: GOOD ( 13.20 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tero Kristo , Phil Reid , Tony Lindgren , Keerthy , Linux Kernel Mailing List , Russell King , Linux-Renesas , Wolfram Sang , Linux OMAP Mailing List , linux-i2c , linux-tegra@vger.kernel.org, Stefan Lengfeld , Andy Shevchenko , Peter Rosin , linux-arm Mailing List Content-Type: multipart/mixed; boundary="===============2948596950361884222==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============2948596950361884222== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="zkokbbl47s6o5i5w" Content-Disposition: inline --zkokbbl47s6o5i5w Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > So, finally, here is the second RFC for supporting I2C transfers in ato= mic > > contexts (i.e. very late). This will need some text because I tried som= e things > > on the way but had to discard them. However, I think it is important to= have > > that documented. >=20 > > Sorry, no TLDR; text here - I think this topic deserves a few words ;) >=20 > Thank you for this work! It was indeed interesting reading. Thanks, glad to hear that :) > And since your series is targetting some exiting use cases, I would > drop as well academic variants of brain-damaged hw design, I think it > worth to go. Well, yes and no. I am with you that some complicated muxed setups could be argued to be way over the top. However, with the panic fault-injector, I can get my simple "PMIC directly (even exclusively) attached to root adapter" setup to stall. By simply ignoring the lock, such setups could work again. But this series does not implement this because it would need a redesign, i.e. tie into i2c_transfer and not later in __i2c_transfer. Yet, before doing this, I was interested in discussion if ignoring the lock is really desirable. This series seems like a valid approach to me if we still want to respect the locking. --zkokbbl47s6o5i5w Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAlyH0/0ACgkQFA3kzBSg Kbb02g//bFuyt6ZF0xKTx4YGhpVUmqDkQpdYzmFvXr2J4/UUeL43QsGvO4P05zuh in13OeiEaWgo1tnE6u9E+DrzEDzPNRiTwER4SB24KbymIncuoyNhBE0UIbuglcbE j1XUxgKQMl4YhZuTKGWZVuBCFaPty4vSxSzjrYgE2pk59ETbZiKOplCkklTHhfVX u77k21N3rO8DJpqhRAsEc2hA5hIH8PTw/TfDlwC6/QQNmHZDHxBS7Ae6t36mkhSS jHhI17n+oXL/WJqcQp0vPaU7rXuS8ZMw9VuoB/djEuZC7POxydKERicPKUKpcM8x iFBWBP370FOQGXxOnCUrwz6j9cooR3D7frKliTmQYWn3WKf1mf7lcW1cVqpxzp5h U+PbpWwI1ZmqixC2XhNfhmKuWaLfIcCj0UacaSge0Fya+P1nIg+RSnm0OBuMa0uW wKrVXMKUPcDY8IFcqygQE0kkmPnws5kQI1/mN62efcLmI5+Z/zNNx+y1Axyv8Mq8 dteeml5Ig8tiRzUDLBmCv/MYMDEJTi4guZe7NLPCz04Z8TGMgXtp0bkoFM5TRwET iWl3w9okHcetxUO8Mf2RkS80p6yy0b0B1Z9ND4IjcSkvunXxRl+ygtwjHtd68iZK ujH2j4D5SGLXuygLnSsjpJXRzN+FjoXnuF1Y880JSCoNhJ6aL0c= =rDLe -----END PGP SIGNATURE----- --zkokbbl47s6o5i5w-- --===============2948596950361884222== 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 --===============2948596950361884222==--