From mboxrd@z Thu Jan 1 00:00:00 1970 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 A0379C4332F for ; Thu, 14 Apr 2022 14:22:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240491AbiDNOY2 (ORCPT ); Thu, 14 Apr 2022 10:24:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343991AbiDNNjd (ORCPT ); Thu, 14 Apr 2022 09:39:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5124D3A700; Thu, 14 Apr 2022 06:36:25 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E04D261D67; Thu, 14 Apr 2022 13:36:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F02E3C385A5; Thu, 14 Apr 2022 13:36:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649943384; bh=rQs5H8uc9j26fZe2HZCqfSJGDUNahqadiRCoxT7AeKA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RS8AftHo4rzVL/ujhw9ezbSTzp7X0/UTmmFuxTiERU1lCenR2yM1cX2QZanUoNmAN gejbe8fxe5QfyjMxOEOL2AF+p7E2r7G9NedyiQeYXriWt6tMRB3xVnvnMAbaLEpUBg A3NftpTTmGERcW3tMj9Rd/XYb/vLAjy7zQZTUTn4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Patrick Rudolph , Marcello Sylvester Bauer , Alan Tull , Guenter Roeck , Sasha Levin Subject: [PATCH 5.4 096/475] hwmon: (pmbus) Add mutex to regulator ops Date: Thu, 14 Apr 2022 15:08:01 +0200 Message-Id: <20220414110857.842403768@linuxfoundation.org> X-Mailer: git-send-email 2.35.2 In-Reply-To: <20220414110855.141582785@linuxfoundation.org> References: <20220414110855.141582785@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Patrick Rudolph [ Upstream commit 686d303ee6301261b422ea51e64833d7909a2c36 ] On PMBUS devices with multiple pages, the regulator ops need to be protected with the update mutex. This prevents accidentally changing the page in a separate thread while operating on the PMBUS_OPERATION register. Tested on Infineon xdpe11280 while a separate thread polls for sensor data. Signed-off-by: Patrick Rudolph Signed-off-by: Marcello Sylvester Bauer Link: https://lore.kernel.org/r/b991506bcbf665f7af185945f70bf9d5cf04637c.1645804976.git.sylv@sylv.io Fixes: ddbb4db4ced1b ("hwmon: (pmbus) Add regulator support") Cc: Alan Tull Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/pmbus/pmbus_core.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index 8470097907bc..b2dfbd1cb543 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -2174,10 +2174,14 @@ static int pmbus_regulator_is_enabled(struct regulator_dev *rdev) { struct device *dev = rdev_get_dev(rdev); struct i2c_client *client = to_i2c_client(dev->parent); + struct pmbus_data *data = i2c_get_clientdata(client); u8 page = rdev_get_id(rdev); int ret; + mutex_lock(&data->update_lock); ret = pmbus_read_byte_data(client, page, PMBUS_OPERATION); + mutex_unlock(&data->update_lock); + if (ret < 0) return ret; @@ -2188,11 +2192,17 @@ static int _pmbus_regulator_on_off(struct regulator_dev *rdev, bool enable) { struct device *dev = rdev_get_dev(rdev); struct i2c_client *client = to_i2c_client(dev->parent); + struct pmbus_data *data = i2c_get_clientdata(client); u8 page = rdev_get_id(rdev); + int ret; - return pmbus_update_byte_data(client, page, PMBUS_OPERATION, - PB_OPERATION_CONTROL_ON, - enable ? PB_OPERATION_CONTROL_ON : 0); + mutex_lock(&data->update_lock); + ret = pmbus_update_byte_data(client, page, PMBUS_OPERATION, + PB_OPERATION_CONTROL_ON, + enable ? PB_OPERATION_CONTROL_ON : 0); + mutex_unlock(&data->update_lock); + + return ret; } static int pmbus_regulator_enable(struct regulator_dev *rdev) -- 2.34.1