From patchwork Wed Jan 15 00:08:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre-Louis Bossart X-Patchwork-Id: 11333009 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 30B9613A0 for ; Wed, 15 Jan 2020 00:13:04 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BA7202467E for ; Wed, 15 Jan 2020 00:13:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="aEwHOT2z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BA7202467E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id CE50E17D1; Wed, 15 Jan 2020 01:12:13 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz CE50E17D1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1579047181; bh=wSkNnae8zeX/s7Z0WaVpDZ+PTO0n1KEZoJqBqBf48Fo=; h=From:To:Date:In-Reply-To:References:Cc:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=aEwHOT2zT2myJh0QYm1Ckm/7HL7yA4oQmLzaXJf/Hnub53GTCFj6wCknM6ri1EIFG AFPXm8nufMCfEM4mZK21gwzTzUTPw7+yBx29x0zuZO5INoK92tp8ptGz+jd8f2OmEM RZT4TN6i8GWmca1Frgvn38Iu6FTIiz0alhwVHMPw= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 43C24F80278; Wed, 15 Jan 2020 01:09:52 +0100 (CET) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa1.perex.cz (Postfix, from userid 50401) id 5C7C0F8026A; Wed, 15 Jan 2020 01:09:48 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on alsa1.perex.cz X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=SPF_HELO_NONE,SPF_NONE, SURBL_BLOCKED,URIBL_BLOCKED autolearn=disabled version=3.4.0 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 5671FF8023E for ; Wed, 15 Jan 2020 01:09:44 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 5671FF8023E X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Jan 2020 16:09:42 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,320,1574150400"; d="scan'208";a="273468554" Received: from emkilgox-mobl2.amr.corp.intel.com (HELO pbossart-mobl3.amr.corp.intel.com) ([10.251.0.151]) by FMSMGA003.fm.intel.com with ESMTP; 14 Jan 2020 16:09:40 -0800 From: Pierre-Louis Bossart To: alsa-devel@alsa-project.org Date: Tue, 14 Jan 2020 18:08:37 -0600 Message-Id: <20200115000844.14695-4-pierre-louis.bossart@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200115000844.14695-1-pierre-louis.bossart@linux.intel.com> References: <20200115000844.14695-1-pierre-louis.bossart@linux.intel.com> MIME-Version: 1.0 Cc: Pierre-Louis Bossart , tiwai@suse.de, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, Ranjani Sridharan , vkoul@kernel.org, broonie@kernel.org, srinivas.kandagatla@linaro.org, jank@cadence.com, slawomir.blauciak@intel.com, Sanyog Kale , Bard liao , Rander Wang Subject: [alsa-devel] [PATCH 03/10] soundwire: bus: fix race condition with initialization_complete signaling X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" Waiting for the enumeration to be complete may not be enough for a Slave driver, there is a possible race condition between resume operations and initializations handled in an interrupt thread, which can results in settings not being fully restored after system or pm_runtime resume. This patch builds on the changes added for enumeration_complete, init_completion() is called when the Slave device becomes UNATTACHED, as done with enumeration_complete. The difference with the enumeration_complete case is that complete() is signaled after the Slave device is fully initialized after the .update_status() callback is called. A Slave device driver can decide to wait on either of the two complete() cases, depending on its initialization code and requirements. Signed-off-by: Rander Wang Signed-off-by: Pierre-Louis Bossart --- drivers/soundwire/bus.c | 8 ++++++++ drivers/soundwire/slave.c | 1 + 2 files changed, 9 insertions(+) diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index a2267c3a1d2d..ea04cf5f5bdc 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -621,6 +621,7 @@ static void sdw_modify_slave_status(struct sdw_slave *slave, __func__, slave->dev_num); init_completion(&slave->enumeration_complete); + init_completion(&slave->initialization_complete); } else if ((status == SDW_SLAVE_ATTACHED) && (slave->status == SDW_SLAVE_UNATTACHED)) { @@ -1025,6 +1026,7 @@ int sdw_handle_slave_status(struct sdw_bus *bus, { enum sdw_slave_status prev_status; struct sdw_slave *slave; + bool attached_initializing; int i, ret = 0; /* first check if any Slaves fell off the bus */ @@ -1070,6 +1072,8 @@ int sdw_handle_slave_status(struct sdw_bus *bus, if (!slave) continue; + attached_initializing = false; + switch (status[i]) { case SDW_SLAVE_UNATTACHED: if (slave->status == SDW_SLAVE_UNATTACHED) @@ -1096,6 +1100,8 @@ int sdw_handle_slave_status(struct sdw_bus *bus, if (prev_status == SDW_SLAVE_ALERT) break; + attached_initializing = true; + ret = sdw_initialize_slave(slave); if (ret) dev_err(bus->dev, @@ -1114,6 +1120,8 @@ int sdw_handle_slave_status(struct sdw_bus *bus, if (ret) dev_err(slave->bus->dev, "Update Slave status failed:%d\n", ret); + if (attached_initializing) + complete(&slave->initialization_complete); } return ret; diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c index e767a78066ee..aace57fae7f8 100644 --- a/drivers/soundwire/slave.c +++ b/drivers/soundwire/slave.c @@ -47,6 +47,7 @@ static int sdw_slave_add(struct sdw_bus *bus, slave->bus = bus; slave->status = SDW_SLAVE_UNATTACHED; init_completion(&slave->enumeration_complete); + init_completion(&slave->initialization_complete); slave->dev_num = 0; init_completion(&slave->probe_complete); slave->probed = false;