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=-21.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,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 AD042C47094 for ; Mon, 14 Jun 2021 18:08:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9594A611AB for ; Mon, 14 Jun 2021 18:08:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235222AbhFNSKz (ORCPT ); Mon, 14 Jun 2021 14:10:55 -0400 Received: from mga01.intel.com ([192.55.52.88]:39923 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234429AbhFNSKx (ORCPT ); Mon, 14 Jun 2021 14:10:53 -0400 IronPort-SDR: lve8VMUkmZyjBLY4Cag6on5+ha9AtzhUIFvI7POoqEAZLwGRcTboZavCyb+THQQNEujGn/qYBE RjT6G2F0UtLg== X-IronPort-AV: E=McAfee;i="6200,9189,10015"; a="227312018" X-IronPort-AV: E=Sophos;i="5.83,273,1616482800"; d="scan'208";a="227312018" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jun 2021 11:08:50 -0700 IronPort-SDR: QMz9h5D4R+M5rWNcbW4LAYtZHDOgB1PVLVWdGUQw1RLWI5jzomHB4u9seA9GkvgLsLDvLqTfmQ DB095xgsO89A== X-IronPort-AV: E=Sophos;i="5.83,273,1616482800"; d="scan'208";a="484166440" Received: from jepowell-mobl1.amr.corp.intel.com (HELO pbossart-mobl3.intel.com) ([10.212.114.106]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jun 2021 11:08:48 -0700 From: Pierre-Louis Bossart To: alsa-devel@alsa-project.org, srinivas.kandagatla@linaro.org Cc: tiwai@suse.de, broonie@kernel.org, vkoul@kernel.org, gregkh@linuxfoundation.org, Bard liao , Rander Wang , Shuming Fan , Jack Yu , Oder Chiou , Jaroslav Kysela , Hui Wang , Pierre-Louis Bossart , Bard Liao , =?UTF-8?q?P=C3=A9ter=20Ujfalusi?= , Liam Girdwood , Takashi Iwai , Kai Vehmanen , linux-kernel@vger.kernel.org (open list) Subject: [PATCH 4/5] ASoC: rt5682-sdw: fix race condition on system suspend Date: Mon, 14 Jun 2021 13:08:14 -0500 Message-Id: <20210614180815.153711-5-pierre-louis.bossart@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210614180815.153711-1-pierre-louis.bossart@linux.intel.com> References: <20210614180815.153711-1-pierre-louis.bossart@linux.intel.com> 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 In the initial driver we cancelled deferred work, but there is still a window of time where a new interrupt could result in new deferred work executed after the link is disabled, leading to an IO error. While we did not see this IO error on RT5682-based platforms, the code pattern is similar to the RT700 case where the IO error was noted, so the fix is added for consistency. This patch uses an 'disable_irq_lock' mutex to prevent new interrupts from happening after the start of the system suspend. The choice of a mutex v. a spinlock is mainly due to the time required to clear interrupts, which requires a command to be transmitted by the SoundWire host IP and acknowledged with an interrupt. The 'interrupt_callback' routine is also not meant to be called from an interrupt context. An additional 'disable_irq' flag prevents race conditions where the status changes before the interrupts are disabled, but the workqueue handling status changes is scheduled after the completion of the system suspend. On resume the interrupts are re-enabled already by the io_init routine so we only clear the flag. The Fixes tag points to a 5.10 commit, there's no need to propagate this change to earlier upstream versions. BugLink: https://github.com/thesofproject/linux/issues/2943 Fixes: 4a55000722d7 ('ASoC: codecs: rt*.c: remove useless pointer cast') Signed-off-by: Pierre-Louis Bossart Reviewed-by: Bard Liao Reviewed-by: Péter Ujfalusi --- sound/soc/codecs/rt5682-sdw.c | 38 +++++++++++++++++++++++++++++++++-- sound/soc/codecs/rt5682.h | 2 ++ 2 files changed, 38 insertions(+), 2 deletions(-) diff --git a/sound/soc/codecs/rt5682-sdw.c b/sound/soc/codecs/rt5682-sdw.c index 54873730bec5..31a4f286043e 100644 --- a/sound/soc/codecs/rt5682-sdw.c +++ b/sound/soc/codecs/rt5682-sdw.c @@ -344,6 +344,8 @@ static int rt5682_sdw_init(struct device *dev, struct regmap *regmap, rt5682->sdw_regmap = regmap; rt5682->is_sdw = true; + mutex_init(&rt5682->disable_irq_lock); + rt5682->regmap = devm_regmap_init(dev, NULL, dev, &rt5682_sdw_indirect_regmap); if (IS_ERR(rt5682->regmap)) { @@ -378,6 +380,8 @@ static int rt5682_io_init(struct device *dev, struct sdw_slave *slave) int ret = 0, loop = 10; unsigned int val; + rt5682->disable_irq = false; + if (rt5682->hw_init) return 0; @@ -679,10 +683,12 @@ static int rt5682_interrupt_callback(struct sdw_slave *slave, dev_dbg(&slave->dev, "%s control_port_stat=%x", __func__, status->control_port); - if (status->control_port & 0x4) { + mutex_lock(&rt5682->disable_irq_lock); + if (status->control_port & 0x4 && !rt5682->disable_irq) { mod_delayed_work(system_power_efficient_wq, &rt5682->jack_detect_work, msecs_to_jiffies(rt5682->irq_work_delay_time)); } + mutex_unlock(&rt5682->disable_irq_lock); return 0; } @@ -740,6 +746,34 @@ static int __maybe_unused rt5682_dev_suspend(struct device *dev) return 0; } +static int __maybe_unused rt5682_dev_system_suspend(struct device *dev) +{ + struct rt5682_priv *rt5682 = dev_get_drvdata(dev); + struct sdw_slave *slave = dev_to_sdw_dev(dev); + int ret; + + if (!rt5682->hw_init) + return 0; + + /* + * prevent new interrupts from being handled after the + * deferred work completes and before the parent disables + * interrupts on the link + */ + mutex_lock(&rt5682->disable_irq_lock); + rt5682->disable_irq = true; + ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, + SDW_SCP_INT1_IMPL_DEF, 0); + mutex_unlock(&rt5682->disable_irq_lock); + + if (ret < 0) { + /* log but don't prevent suspend from happening */ + dev_dbg(&slave->dev, "%s: could not disable imp-def interrupts\n:", __func__); + } + + return rt5682_dev_suspend(dev); +} + static int __maybe_unused rt5682_dev_resume(struct device *dev) { struct sdw_slave *slave = dev_to_sdw_dev(dev); @@ -768,7 +802,7 @@ static int __maybe_unused rt5682_dev_resume(struct device *dev) } static const struct dev_pm_ops rt5682_pm = { - SET_SYSTEM_SLEEP_PM_OPS(rt5682_dev_suspend, rt5682_dev_resume) + SET_SYSTEM_SLEEP_PM_OPS(rt5682_dev_system_suspend, rt5682_dev_resume) SET_RUNTIME_PM_OPS(rt5682_dev_suspend, rt5682_dev_resume, NULL) }; diff --git a/sound/soc/codecs/rt5682.h b/sound/soc/codecs/rt5682.h index 74ff66767016..b59221048ebf 100644 --- a/sound/soc/codecs/rt5682.h +++ b/sound/soc/codecs/rt5682.h @@ -1415,6 +1415,8 @@ struct rt5682_priv { struct regulator_bulk_data supplies[RT5682_NUM_SUPPLIES]; struct delayed_work jack_detect_work; struct delayed_work jd_check_work; + struct mutex disable_irq_lock; /* imp-def irq lock protection */ + bool disable_irq; struct mutex calibrate_mutex; struct sdw_slave *slave; enum sdw_slave_status status; -- 2.25.1