From patchwork Thu Oct 19 07:35:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herve Codina X-Patchwork-Id: 736004 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 85A9DC41513 for ; Thu, 19 Oct 2023 07:35:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232879AbjJSHfp (ORCPT ); Thu, 19 Oct 2023 03:35:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232810AbjJSHfo (ORCPT ); Thu, 19 Oct 2023 03:35:44 -0400 Received: from relay3-d.mail.gandi.net (relay3-d.mail.gandi.net [217.70.183.195]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DFBE4126; Thu, 19 Oct 2023 00:35:41 -0700 (PDT) Received: by mail.gandi.net (Postfix) with ESMTPA id BECF76001A; Thu, 19 Oct 2023 07:35:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1697700940; 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=wFxDhOHA1nOXegi4jc03C6n7+wwkMRGPrbKDfHusrSk=; b=oIZDd51e4WPDovOewLVpzqon29hf6yqKMU4ml/UupSHOM0hr7uGRWapYHOWcoPUh+AYRcp RoYh6KyVzV+fFk/c5u/5uvEPAT90V1hu2D00E1ftPqL8bHD04k8PnE362UOfYH+GLwcVkD +99+4hRHNILhBrp2RWIyD7TTu3RXLj5n46D4XaW0RdTp+Lip8i7c3Kba12b9US1a2hiWp7 WneLhRMx+9AQEWl/f921YBMV5bEx/P+jMwKFOb5iHyXgj4ZvhM4aLW+XqtMvXTQSNILcTl yl2aqUvlAQASPzCBmD2UQX/WKxDekAaFEG8L1ZnGAga5zCB8rm/uR6pU7E7NaQ== From: Herve Codina To: Wolfram Sang , Peter Rosin Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Allan Nielsen , Horatiu Vultur , Steen Hegelund , Thomas Petazzoni , Herve Codina Subject: [PATCH 3/3] i2c: muxes: i2c-mux-gpmux: Use of_get_i2c_adapter_by_node() Date: Thu, 19 Oct 2023 09:35:30 +0200 Message-ID: <20231019073533.386563-4-herve.codina@bootlin.com> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20231019073533.386563-1-herve.codina@bootlin.com> References: <20231019073533.386563-1-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 overflow over zero of the parent adapter user counter. Use the dedicated function, of_get_i2c_adapter_by_node(), to handle correctly the module refcount. Signed-off-by: Herve Codina Acked-by: Peter Rosin --- 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);