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_HELO_NONE,SPF_PASS,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 BBC04C2BA19 for ; Wed, 15 Apr 2020 08:27:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A290B206E9 for ; Wed, 15 Apr 2020 08:27:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2894485AbgDOI1T (ORCPT ); Wed, 15 Apr 2020 04:27:19 -0400 Received: from sauhun.de ([88.99.104.3]:49304 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2894461AbgDOI1O (ORCPT ); Wed, 15 Apr 2020 04:27:14 -0400 Received: from localhost (p54B33507.dip0.t-ipconnect.de [84.179.53.7]) by pokefinder.org (Postfix) with ESMTPSA id 956F72C1F58; Wed, 15 Apr 2020 10:27:12 +0200 (CEST) Date: Wed, 15 Apr 2020 10:27:12 +0200 From: Wolfram Sang To: Wolfram Sang Cc: linux-i2c@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-i3c@lists.infradead.org, Kieran Bingham , Niklas =?utf-8?Q?S=C3=B6derlund?= , Luca Ceresoli , Jacopo Mondi , Laurent Pinchart , Vladimir Zapolskiy , linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v2 0/6] i2c: of: reserve unknown and ancillary addresses Message-ID: <20200415082712.GD1141@ninjato> References: <20200318150059.21714-1-wsa+renesas@sang-engineering.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="DiL7RhKs8rK9YGuF" Content-Disposition: inline In-Reply-To: <20200318150059.21714-1-wsa+renesas@sang-engineering.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org --DiL7RhKs8rK9YGuF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Status update on this series: > TODO: make sure there are no concurrency issues in patch 6 when handling > the struct i2c_client. This turns out to be annoying. How to make sure that we don't modify the i2c_client while the adapter it is sitting on just gets removed. AFAICS we need a new locking scheme just for that and I am not convinced this is the way forward. Also, there is still this small room for regressing when there are DTs having multiple addresses specified in the DT and the drivers use i2c_new_dummy_client on these addresses. I have verified that no in-tree users of i2c_new_dummy (and friends) do work on extra addresses but still I'd like to completely avoid this potential regression. One solution to both problems would be to unregister the reserved device when its address is requested. I am working on this prototype currently. However, I am not sure yet if one issue might make this approach messy: re-registering the reserved device when the probe of the requested address fails. We will see... --DiL7RhKs8rK9YGuF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAl6WxWAACgkQFA3kzBSg Kbae9w//RJrz6RPLZSRlLMCbftnMujapFw1Mb4d6vzU283/gdeAkzuz/C38XWPA8 xcUJsFWpHCDYOhaXdav0Jf7UL5KssTT2XdrdWneLKmn/QN/8NdeOkiROzTq2pavX lcQhC9V9tjGe09MfRlpyg6mZDti/09vxJ6QZbOVpHyJg5chqht1NgwjYtAVCwsby Fd3ucuyN5r1rPwyRXuVVnXQ0D/itOsacyLzpAfA3BQNlLPWe71fsytlCrlPX31Ys +yh7z+0BAprWcPNNXLVrOG87+Agi7p426lpV94D5BsoEbSbdMC97vLShzooOVFBS BXhziJ66I1btW/yaXBYO9RWcm0bPH/yN0NTFE9X3H7OqTcVh9TFin33oGR/PEZF0 gkvDnFLOfCUWLO/697U8x+Km0bN/rsOcdapGkjZaeSxZF/QQ3vWGo4S3AibS9GPA scR//jSVYL+iphxlOa08YRqSfPd2L32vDirk4iTsKTt45850jzGcilFkrEKx4uUm UTp5VmQkIoVj0CO+E7ByjkM+5yG2o9CTNZHY5X5kLsaiETjGCD0yH4SNrADpiY4o F13eHJvBFVGtjR969TuiT4tpAzRh+xKAuJNfC3Z8yRyT/uKSS+RAajfc2SCKoWxC 6iSF2T57Tclts7MFdaBCeYN5f16uSvyQR5UTSFezGHb1qd642wI= =blKZ -----END PGP SIGNATURE----- --DiL7RhKs8rK9YGuF--