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 X-Spam-Level: X-Spam-Status: No, score=-10.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 48AD4C04EB9 for ; Wed, 5 Dec 2018 09:36:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0EDA920850 for ; Wed, 5 Dec 2018 09:36:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="InyYxgtL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0EDA920850 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727557AbeLEJgT (ORCPT ); Wed, 5 Dec 2018 04:36:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:37932 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727347AbeLEJgQ (ORCPT ); Wed, 5 Dec 2018 04:36:16 -0500 Received: from sasha-vm.mshome.net (unknown [213.57.143.11]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B26EF2084C; Wed, 5 Dec 2018 09:36:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1544002575; bh=vZPSzNYPMiOhOKC4E6xYUZ0lqyp+YSxDWyBqB4W23Yg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=InyYxgtLK00P7aajBK50aUiv2ryi3EXqbz50U7Yup2uSW35BxzW/U0cfeLos+vh5W dJisrLS6kEiG29d7Qnq18OCHmGDKMV88FyR9gdDynogB/QCLKktozA9q1XYuPf28Xl eYs1PbiAswchFMN7EryYMcQoljVNYnjFlLPqNUU8= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Martin Kelly , Stable@vger.kernel.org, Jonathan Cameron , Sasha Levin , linux-iio@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 004/123] iio:st_magn: Fix enable device after trigger Date: Wed, 5 Dec 2018 04:33:56 -0500 Message-Id: <20181205093555.5386-4-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181205093555.5386-1-sashal@kernel.org> References: <20181205093555.5386-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Martin Kelly [ Upstream commit fe5192ac81ad0d4dfe1395d11f393f0513c15f7f ] Currently, we enable the device before we enable the device trigger. At high frequencies, this can cause interrupts that don't yet have a poll function associated with them and are thus treated as spurious. At high frequencies with level interrupts, this can even cause an interrupt storm of repeated spurious interrupts (~100,000 on my Beagleboard with the LSM9DS1 magnetometer). If these repeat too much, the interrupt will get disabled and the device will stop functioning. To prevent these problems, enable the device prior to enabling the device trigger, and disable the divec prior to disabling the trigger. This means there's no window of time during which the device creates interrupts but we have no trigger to answer them. Fixes: 90efe055629 ("iio: st_sensors: harden interrupt handling") Signed-off-by: Martin Kelly Tested-by: Denis Ciocca Cc: Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin --- drivers/iio/magnetometer/st_magn_buffer.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) diff --git a/drivers/iio/magnetometer/st_magn_buffer.c b/drivers/iio/magnetometer/st_magn_buffer.c index 0a9e8fadfa9d..37ab30566464 100644 --- a/drivers/iio/magnetometer/st_magn_buffer.c +++ b/drivers/iio/magnetometer/st_magn_buffer.c @@ -30,11 +30,6 @@ int st_magn_trig_set_state(struct iio_trigger *trig, bool state) return st_sensors_set_dataready_irq(indio_dev, state); } -static int st_magn_buffer_preenable(struct iio_dev *indio_dev) -{ - return st_sensors_set_enable(indio_dev, true); -} - static int st_magn_buffer_postenable(struct iio_dev *indio_dev) { int err; @@ -50,7 +45,7 @@ static int st_magn_buffer_postenable(struct iio_dev *indio_dev) if (err < 0) goto st_magn_buffer_postenable_error; - return err; + return st_sensors_set_enable(indio_dev, true); st_magn_buffer_postenable_error: kfree(mdata->buffer_data); @@ -63,11 +58,11 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev) int err; struct st_sensor_data *mdata = iio_priv(indio_dev); - err = iio_triggered_buffer_predisable(indio_dev); + err = st_sensors_set_enable(indio_dev, false); if (err < 0) goto st_magn_buffer_predisable_error; - err = st_sensors_set_enable(indio_dev, false); + err = iio_triggered_buffer_predisable(indio_dev); st_magn_buffer_predisable_error: kfree(mdata->buffer_data); @@ -75,7 +70,6 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev) } static const struct iio_buffer_setup_ops st_magn_buffer_setup_ops = { - .preenable = &st_magn_buffer_preenable, .postenable = &st_magn_buffer_postenable, .predisable = &st_magn_buffer_predisable, }; -- 2.17.1