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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 A7E06C43333 for ; Mon, 15 Mar 2021 14:04:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7CB8A64F02 for ; Mon, 15 Mar 2021 14:04:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234091AbhCOOCz (ORCPT ); Mon, 15 Mar 2021 10:02:55 -0400 Received: from mail.kernel.org ([198.145.29.99]:34042 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231840AbhCON44 (ORCPT ); Mon, 15 Mar 2021 09:56:56 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8181B64EEE; Mon, 15 Mar 2021 13:56:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615816616; bh=zvC60x0TDrgUee+EUTxBvbrcxT8cqVWicznokVysHn0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jzv223T2jdY8U+PjpTlrHr3Q+qN5kKC70m1OsnJnY5SGoi6Z2m//fMYHlqa4CwuDR UOn4brgBApI7Te4ZoximKrU70OaVjMHIN5i5W18UlgAIQYpwZznbfGTAeBR7FcWqjO y5xGK76MkhvMgF4zfk1y/cIwxtVYD2xXZMm63MTk= From: gregkh@linuxfoundation.org To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marc Kleine-Budde , Torin Cooper-Bennun Subject: [PATCH 5.10 015/290] can: tcan4x5x: tcan4x5x_init(): fix initialization - clear MRAM before entering Normal Mode Date: Mon, 15 Mar 2021 14:51:48 +0100 Message-Id: <20210315135542.459949146@linuxfoundation.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210315135541.921894249@linuxfoundation.org> References: <20210315135541.921894249@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Greg Kroah-Hartman From: Torin Cooper-Bennun commit 2712625200ed69c642b9abc3a403830c4643364c upstream. This patch prevents a potentially destructive race condition. The device is fully operational on the bus after entering Normal Mode, so zeroing the MRAM after entering this mode may lead to loss of information, e.g. new received messages. This patch fixes the problem by first initializing the MRAM, then bringing the device into Normale Mode. Fixes: 5443c226ba91 ("can: tcan4x5x: Add tcan4x5x driver to the kernel") Link: https://lore.kernel.org/r/20210226163440.313628-1-torin@maxiluxsystems.com Suggested-by: Marc Kleine-Budde Signed-off-by: Torin Cooper-Bennun Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- drivers/net/can/m_can/tcan4x5x.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/net/can/m_can/tcan4x5x.c +++ b/drivers/net/can/m_can/tcan4x5x.c @@ -328,14 +328,14 @@ static int tcan4x5x_init(struct m_can_cl if (ret) return ret; + /* Zero out the MCAN buffers */ + m_can_init_ram(cdev); + ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG, TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_NORMAL); if (ret) return ret; - /* Zero out the MCAN buffers */ - m_can_init_ram(cdev); - return ret; }