From nobody Tue Dec 16 16:39:08 2025 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 D274EC77B73 for ; Mon, 8 May 2023 04:41:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232456AbjEHElU (ORCPT ); Mon, 8 May 2023 00:41:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229540AbjEHElS (ORCPT ); Mon, 8 May 2023 00:41:18 -0400 Received: from hust.edu.cn (unknown [202.114.0.240]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A76561569E; Sun, 7 May 2023 21:41:16 -0700 (PDT) Received: from amy-vm.localdomain ([10.12.169.124]) (user=yejunyan@hust.edu.cn mech=LOGIN bits=0) by mx1.hust.edu.cn with ESMTP id 3484bSF4021609-3484bSF5021609 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NO); Mon, 8 May 2023 12:37:33 +0800 From: Junyan Ye To: Lorenzo Pieralisi , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Rob Herring , Bjorn Helgaas , Wei Yongjun , Linus Walleij , Andrew Murray Cc: hust-os-kernel-patches@googlegroups.com, Junyan Ye , Dongliang Mu , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] pci: controller: pci-ftpci100: Release the clock resources Date: Mon, 8 May 2023 12:36:41 +0800 Message-Id: <20230508043641.23807-1-yejunyan@hust.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FEAS-AUTH-USER: yejunyan@hust.edu.cn Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Smatch reported: 1. drivers/pci/controller/pci-ftpci100.c:526 faraday_pci_probe() warn: 'clk' from clk_prepare_enable() not released on lines: 442,451,462,478,512,= 517. 2. drivers/pci/controller/pci-ftpci100.c:526 faraday_pci_probe() warn: 'p->bus_clk' from clk_prepare_enable() not released on lines: 451,462,478,5= 12,517. The clock resource is obtained by devm_clk_get(), and then clk_prepare_enable() makes the clock resource ready for use. After that, clk_disable_unprepare() should be called to release the clock resource when it is no longer needed. However, while doing some error handling in faraday_pci_probe(), clk_disable_unprepare() is not called to release clk and p->bus_clk before returning. These return lines are exactly 442, 451, 462, 478, 512, 517. Fix this warning by replacing devm_clk_get() with devm_clk_get_enabled(), which is equivalent to devm_clk_get() + clk_prepare_enable(). And with devm_clk_get_enabled(), the clock will automatically be disabled, unprepared and freed when the device is unbound from the bus. Fixes: b3c433efb8a3 ("PCI: faraday: Fix wrong pointer passed to PTR_ERR()") Fixes: 2eeb02b28579 ("PCI: faraday: Add clock handling") Fixes: 783a862563f7 ("PCI: faraday: Use pci_parse_request_of_pci_ranges()") Fixes: d3c68e0a7e34 ("PCI: faraday: Add Faraday Technology FTPCI100 PCI Hos= t Bridge driver") Fixes: f1e8bd21e39e ("PCI: faraday: Convert IRQ masking to raw PCI config a= ccessors") Reviewed-by: Dongliang Mu Signed-off-by: Junyan Ye Reviewed-by: Linus Walleij --- v2 -> v3: Rebase to v6.4-rc1 and modify commit message. v1 -> v2: Switch from clk_disable_unprepare() to devm_clk_get_enabled() to = release the clock. This issue is found by static analyzer. drivers/pci/controller/pci-ftpci100.c | 14 ++------------ 1 file changed, 2 insertions(+), 12 deletions(-) diff --git a/drivers/pci/controller/pci-ftpci100.c b/drivers/pci/controller= /pci-ftpci100.c index ecd3009df586..6e7981d2ed5e 100644 --- a/drivers/pci/controller/pci-ftpci100.c +++ b/drivers/pci/controller/pci-ftpci100.c @@ -429,22 +429,12 @@ static int faraday_pci_probe(struct platform_device *= pdev) p->dev =3D dev; =20 /* Retrieve and enable optional clocks */ - clk =3D devm_clk_get(dev, "PCLK"); + clk =3D devm_clk_get_enabled(dev, "PCLK"); if (IS_ERR(clk)) return PTR_ERR(clk); - ret =3D clk_prepare_enable(clk); - if (ret) { - dev_err(dev, "could not prepare PCLK\n"); - return ret; - } - p->bus_clk =3D devm_clk_get(dev, "PCICLK"); + p->bus_clk =3D devm_clk_get_enabled(dev, "PCICLK"); if (IS_ERR(p->bus_clk)) return PTR_ERR(p->bus_clk); - ret =3D clk_prepare_enable(p->bus_clk); - if (ret) { - dev_err(dev, "could not prepare PCICLK\n"); - return ret; - } =20 p->base =3D devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(p->base)) --=20 2.25.1