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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 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 84029C43603 for ; Mon, 9 Dec 2019 14:41:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B0D524656 for ; Mon, 9 Dec 2019 14:41:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727771AbfLIOlj (ORCPT ); Mon, 9 Dec 2019 09:41:39 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:45780 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726687AbfLIOli (ORCPT ); Mon, 9 Dec 2019 09:41:38 -0500 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: eballetbo) with ESMTPSA id 5505B28B60A Subject: Re: [PATCH 4/4] platform/chrome: i2c: i2c-cros-ec-tunnel: Convert i2c tunnel to MFD Cell To: Lee Jones , Raul E Rangel Cc: Wolfram Sang , Akshu.Agrawal@amd.com, Guenter Roeck , Chanwoo Choi , linux-kernel@vger.kernel.org, Alexandre Belloni , linux-i2c@vger.kernel.org, Benson Leung References: <20191121211053.48861-1-rrangel@chromium.org> <20191121140830.4.Iddc7dd74f893297cb932e9825d413e7890633b3d@changeid> <20191209131745.GM3468@dell> From: Enric Balletbo i Serra Message-ID: <6f6b0ac7-37d8-e2a1-3249-223905c2a5b1@collabora.com> Date: Mon, 9 Dec 2019 15:41:33 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20191209131745.GM3468@dell> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Lee, On 9/12/19 14:17, Lee Jones wrote: > On Thu, 21 Nov 2019, Raul E Rangel wrote: > >> If the i2c-cros-ec-tunnel driver is compiled into the kernel, it is >> possible that i2c-cros-ec-tunnel could be probed before cros_ec_XXX >> has finished initializing and setting the drvdata. This would cause a >> NULL pointer panic. >> >> Converting this driver over to an MFD solves the problem and aligns with >> where the cros_ec is going. >> >> Signed-off-by: Raul E Rangel >> --- >> You can now see the device node lives under the mfd device. >> >> $ find /sys/bus/platform/devices/cros-ec-dev.0.auto/cros-ec-i2c-tunnel.12.auto/ -iname firmware_node -exec ls -l '{}' \; >> /sys/bus/platform/devices/cros-ec-dev.0.auto/cros-ec-i2c-tunnel.12.auto/firmware_node -> ../../../../../../LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:1c/PNP0C09:00/GOOG0004:00/GOOG0012:00 >> /sys/bus/platform/devices/cros-ec-dev.0.auto/cros-ec-i2c-tunnel.12.auto/i2c-9/firmware_node -> ../../../../../../../LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:1c/PNP0C09:00/GOOG0004:00/GOOG0012:00 >> /sys/bus/platform/devices/cros-ec-dev.0.auto/cros-ec-i2c-tunnel.12.auto/i2c-9/i2c-10EC5682:00/firmware_node -> ../../../../../../../../LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:1c/PNP0C09:00/GOOG0004:00/GOOG0012:00/10EC5682:00 >> >> drivers/i2c/busses/i2c-cros-ec-tunnel.c | 36 +++++++++---------------- >> drivers/mfd/cros_ec_dev.c | 19 +++++++++++++ > > For my own reference: > Acked-for-MFD-by: Lee Jones > Note that there is a v2 for this patch and I did some comments [1] Thanks, Enric [1] https://patchwork.ozlabs.org/patch/1200560/