Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932263AbdCUE7d (ORCPT ); Tue, 21 Mar 2017 00:59:33 -0400 Received: from cdptpa-outbound-snat.email.rr.com ([107.14.166.229]:36660 "EHLO cdptpa-oedge-vip.email.rr.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932120AbdCUE7c (ORCPT ); Tue, 21 Mar 2017 00:59:32 -0400 From: Jeremy Linton To: linux-kernel@vger.kernel.org Cc: broonie@kernel.org, lgirdwood@gmail.com, puck.chen@hisilicon.com, lee.jones@linaro.org, Jeremy Linton Subject: [PATCH 2/2] regulator: hi655x: Bump parent pmic module use count Date: Mon, 20 Mar 2017 23:53:41 -0500 Message-Id: <20170321045341.4833-3-lintonrjeremy@gmail.com> X-Mailer: git-send-email 2.10.2 In-Reply-To: <20170321045341.4833-1-lintonrjeremy@gmail.com> References: <20170321045341.4833-1-lintonrjeremy@gmail.com> X-RR-Connecting-IP: 107.14.168.88:25 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2047 Lines: 70 The hi655x-regulator driver depends on the parent pmic/mfc device driver but doesn't increase its use count. This results in system crashes if the parent module is unloaded while the regulators are still in use. Add explicit module get/put calls to keep the parent from being unloaded. Signed-off-by: Jeremy Linton --- drivers/regulator/hi655x-regulator.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/drivers/regulator/hi655x-regulator.c b/drivers/regulator/hi655x-regulator.c index aca1846..5a461d4 100644 --- a/drivers/regulator/hi655x-regulator.c +++ b/drivers/regulator/hi655x-regulator.c @@ -185,16 +185,29 @@ static int hi655x_regulator_probe(struct platform_device *pdev) struct hi655x_pmic *pmic; struct regulator_config config = { }; struct regulator_dev *rdev; + struct device *parent = pdev->dev.parent; - pmic = dev_get_drvdata(pdev->dev.parent); + if (!parent) { + dev_err(&pdev->dev, "no regulator parent node\n"); + return -ENODEV; + } + + pmic = dev_get_drvdata(parent); if (!pmic) { dev_err(&pdev->dev, "no pmic in the regulator parent node\n"); return -ENODEV; } + if (!try_module_get(parent->driver->owner)) { + dev_err(&pdev->dev, "unable to get parent module\n"); + return -ENODEV; + } + regulator = devm_kzalloc(&pdev->dev, sizeof(*regulator), GFP_KERNEL); - if (!regulator) + if (!regulator) { + module_put(parent->driver->owner); return -ENOMEM; + } platform_set_drvdata(pdev, regulator); @@ -214,11 +227,20 @@ static int hi655x_regulator_probe(struct platform_device *pdev) return 0; } +static int hi655x_regulator_remove(struct platform_device *pdev) +{ + struct device *parent = pdev->dev.parent; + + module_put(parent->driver->owner); + return 0; +} + static struct platform_driver hi655x_regulator_driver = { .driver = { .name = "hi655x-regulator", }, .probe = hi655x_regulator_probe, + .remove = hi655x_regulator_remove }; module_platform_driver(hi655x_regulator_driver); -- 2.10.2