From patchwork Thu Jan 16 23:15:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 233669 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, 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 5DA91C33CAF for ; Thu, 16 Jan 2020 23:48:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 31FB82077C for ; Thu, 16 Jan 2020 23:48:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579218507; bh=tL8PqyFVxZml9STucnW49Uk4VHzgmxIX2lyzMjCWgr4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WHqiMBpNEEQwBsJGXiTPTz+dPSKUma4HKG3DiVw6AKwLOxax9MKQ9vXKH+FTSOJnB bgnzyzkhDyTmnUn07U5R1VovS7TWUc08OA59OJhbnhLVA3YVTxV3VBxgxrvzHy3GcO Qdnt8ZnD/jD01XO99sPeUVy2JCsAGL3aQnlcOf/E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390458AbgAPXTo (ORCPT ); Thu, 16 Jan 2020 18:19:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:45660 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390456AbgAPXTl (ORCPT ); Thu, 16 Jan 2020 18:19:41 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E50F62072E; Thu, 16 Jan 2020 23:19:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579216780; bh=tL8PqyFVxZml9STucnW49Uk4VHzgmxIX2lyzMjCWgr4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QNDv0LQcS3U8mVdjDDvvIBNtWSrAQtMBXGnN+yhZw+rgVd++sMVGjCI/HdigPxm7z eVL3RRUMYItmCYjPRcrLJIfELpzZEDo1+O1Zfbet6Di5BG2VsrSi+KTNWuBwqKtMNW wOl5IL+32jWoFo+d21ipDArQHqTj274QNLzG5suU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefan Wahren , Wolfram Sang Subject: [PATCH 5.4 008/203] i2c: bcm2835: Store pointer to bus clock Date: Fri, 17 Jan 2020 00:15:25 +0100 Message-Id: <20200116231745.723014121@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200116231745.218684830@linuxfoundation.org> References: <20200116231745.218684830@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Stefan Wahren commit 3b722da6672df8392f9c43d7c7e04bddd81d7e37 upstream. The commit bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF") introduced a NULL pointer dereference on driver unload. It seems that we can't fetch the bus clock via devm_clk_get in bcm2835_i2c_remove. As an alternative approach store a pointer to the bus clock in the private driver structure. Fixes: bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF") Signed-off-by: Stefan Wahren Signed-off-by: Wolfram Sang Signed-off-by: Greg Kroah-Hartman --- drivers/i2c/busses/i2c-bcm2835.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) --- a/drivers/i2c/busses/i2c-bcm2835.c +++ b/drivers/i2c/busses/i2c-bcm2835.c @@ -58,6 +58,7 @@ struct bcm2835_i2c_dev { struct i2c_adapter adapter; struct completion completion; struct i2c_msg *curr_msg; + struct clk *bus_clk; int num_msgs; u32 msg_err; u8 *msg_buf; @@ -404,7 +405,6 @@ static int bcm2835_i2c_probe(struct plat struct resource *mem, *irq; int ret; struct i2c_adapter *adap; - struct clk *bus_clk; struct clk *mclk; u32 bus_clk_rate; @@ -427,11 +427,11 @@ static int bcm2835_i2c_probe(struct plat return PTR_ERR(mclk); } - bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev); + i2c_dev->bus_clk = bcm2835_i2c_register_div(&pdev->dev, mclk, i2c_dev); - if (IS_ERR(bus_clk)) { + if (IS_ERR(i2c_dev->bus_clk)) { dev_err(&pdev->dev, "Could not register clock\n"); - return PTR_ERR(bus_clk); + return PTR_ERR(i2c_dev->bus_clk); } ret = of_property_read_u32(pdev->dev.of_node, "clock-frequency", @@ -442,13 +442,13 @@ static int bcm2835_i2c_probe(struct plat bus_clk_rate = 100000; } - ret = clk_set_rate_exclusive(bus_clk, bus_clk_rate); + ret = clk_set_rate_exclusive(i2c_dev->bus_clk, bus_clk_rate); if (ret < 0) { dev_err(&pdev->dev, "Could not set clock frequency\n"); return ret; } - ret = clk_prepare_enable(bus_clk); + ret = clk_prepare_enable(i2c_dev->bus_clk); if (ret) { dev_err(&pdev->dev, "Couldn't prepare clock"); return ret; @@ -491,10 +491,9 @@ static int bcm2835_i2c_probe(struct plat static int bcm2835_i2c_remove(struct platform_device *pdev) { struct bcm2835_i2c_dev *i2c_dev = platform_get_drvdata(pdev); - struct clk *bus_clk = devm_clk_get(i2c_dev->dev, "div"); - clk_rate_exclusive_put(bus_clk); - clk_disable_unprepare(bus_clk); + clk_rate_exclusive_put(i2c_dev->bus_clk); + clk_disable_unprepare(i2c_dev->bus_clk); free_irq(i2c_dev->irq, i2c_dev); i2c_del_adapter(&i2c_dev->adapter);