From patchwork Fri Oct 20 15:30:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herve Codina X-Patchwork-Id: 736466 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CE1EC001DF for ; Fri, 20 Oct 2023 15:30:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377753AbjJTPao (ORCPT ); Fri, 20 Oct 2023 11:30:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377726AbjJTPa3 (ORCPT ); Fri, 20 Oct 2023 11:30:29 -0400 Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68BDC1A8; Fri, 20 Oct 2023 08:30:27 -0700 (PDT) Received: by mail.gandi.net (Postfix) with ESMTPA id DF5DAC000D; Fri, 20 Oct 2023 15:30:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1697815826; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LpkSQeveUeewBTxaJFyVrBiY7AoHvN0hE8hZ52cDayY=; b=OuMTtuTsfHK6E+16NET+zVwtnX4o+Xw9/X7wdTuWuRBpjJ5jdIChiURZAUu5RmWLvsB2T3 9T9vA38ADHg9rQhKOv0J2IKStBUWX73xMAJIKH6ebMUfsLlEeyo/V/cPqMJbHHCDLRdFT3 whXqROauSPkco0ha6pH7rqag50cww3Nehn5ycYMB1k3jMYZVaOQyRNdfFeCxJ1mCHV3IaD tQ8gvIxiTf2fiX7znhONmol9gf1Ig7oDlavgMgKgttyQAZcvsUJuuJNufpWay2pmDszPKH QgwDu2WUlMViWKQK0xdy2jbR1VlcbfaEFJHJqfp230QjADYt4b8TkrhP7Nm7Ew== From: Herve Codina To: Wolfram Sang , Peter Rosin , Stephen Warren , Rob Herring , Greg Kroah-Hartman , Jonathan Cameron Cc: Wolfram Sang , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Allan Nielsen , Horatiu Vultur , Steen Hegelund , Thomas Petazzoni , Herve Codina , stable@vger.kernel.org, Jonathan Cameron Subject: [PATCH v3 3/3] i2c: muxes: i2c-mux-gpmux: Use of_get_i2c_adapter_by_node() Date: Fri, 20 Oct 2023 17:30:13 +0200 Message-ID: <20231020153017.759926-4-herve.codina@bootlin.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231020153017.759926-1-herve.codina@bootlin.com> References: <20231020153017.759926-1-herve.codina@bootlin.com> MIME-Version: 1.0 X-GND-Sasl: herve.codina@bootlin.com Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org i2c-mux-gpmux uses the pair of_find_i2c_adapter_by_node() / i2c_put_adapter(). These pair alone is not correct to properly lock the I2C parent adapter. Indeed, i2c_put_adapter() decrements the module refcount while of_find_i2c_adapter_by_node() does not increment it. This leads to an underflow of the parent module refcount. Use the dedicated function, of_get_i2c_adapter_by_node(), to handle correctly the module refcount. Fixes: ac8498f0ce53 ("i2c: i2c-mux-gpmux: new driver") Signed-off-by: Herve Codina Cc: stable@vger.kernel.org Acked-by: Peter Rosin Reviewed-by: Jonathan Cameron --- drivers/i2c/muxes/i2c-mux-gpmux.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/muxes/i2c-mux-gpmux.c b/drivers/i2c/muxes/i2c-mux-gpmux.c index baccf4bfaf02..8305661e1253 100644 --- a/drivers/i2c/muxes/i2c-mux-gpmux.c +++ b/drivers/i2c/muxes/i2c-mux-gpmux.c @@ -52,7 +52,7 @@ static struct i2c_adapter *mux_parent_adapter(struct device *dev) dev_err(dev, "Cannot parse i2c-parent\n"); return ERR_PTR(-ENODEV); } - parent = of_find_i2c_adapter_by_node(parent_np); + parent = of_get_i2c_adapter_by_node(parent_np); of_node_put(parent_np); if (!parent) return ERR_PTR(-EPROBE_DEFER);