From patchwork Mon May 11 11:02:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Reichel X-Patchwork-Id: 11540205 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 54331139F for ; Mon, 11 May 2020 11:02:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 45BC720736 for ; Mon, 11 May 2020 11:02:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727093AbgEKLC0 (ORCPT ); Mon, 11 May 2020 07:02:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725993AbgEKLCZ (ORCPT ); Mon, 11 May 2020 07:02:25 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94EA9C061A0C; Mon, 11 May 2020 04:02:25 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: sre) with ESMTPSA id A06152A0AF8 Received: by jupiter.universe (Postfix, from userid 1000) id 3FEC34800FF; Mon, 11 May 2020 13:02:21 +0200 (CEST) From: Sebastian Reichel To: Support Opensource , Jean Delvare , Guenter Roeck Cc: Lee Jones , linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@collabora.com, Samu Nuutamo , Sebastian Reichel Subject: [PATCH] hwmon: da9052: Synchronize access with mfd Date: Mon, 11 May 2020 13:02:19 +0200 Message-Id: <20200511110219.68188-1-sebastian.reichel@collabora.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org From: Samu Nuutamo When tsi-as-adc is configured it is possible for in7[0123]_input read to return an incorrect value if a concurrent read to in[456]_input is performed. This is caused by a concurrent manipulation of the mux channel without proper locking as hwmon and mfd use different locks for synchronization. Switch hwmon to use the same lock as mfd when accessing the TSI channel. Fixes: 4f16cab19a3d5 ("hwmon: da9052: Add support for TSI channel") Signed-off-by: Samu Nuutamo [rebase to current master, reword commit message slightly] Signed-off-by: Sebastian Reichel --- drivers/hwmon/da9052-hwmon.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c index 53b517dbe7e6..4af2fc309c28 100644 --- a/drivers/hwmon/da9052-hwmon.c +++ b/drivers/hwmon/da9052-hwmon.c @@ -244,9 +244,9 @@ static ssize_t da9052_tsi_show(struct device *dev, int channel = to_sensor_dev_attr(devattr)->index; int ret; - mutex_lock(&hwmon->hwmon_lock); + mutex_lock(&hwmon->da9052->auxadc_lock); ret = __da9052_read_tsi(dev, channel); - mutex_unlock(&hwmon->hwmon_lock); + mutex_unlock(&hwmon->da9052->auxadc_lock); if (ret < 0) return ret;