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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 515CBC432C3 for ; Thu, 14 Nov 2019 18:17:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3013B2072E for ; Thu, 14 Nov 2019 18:17:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727376AbfKNSR4 (ORCPT ); Thu, 14 Nov 2019 13:17:56 -0500 Received: from mga03.intel.com ([134.134.136.65]:36355 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727344AbfKNSRw (ORCPT ); Thu, 14 Nov 2019 13:17:52 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Nov 2019 10:17:52 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.68,304,1569308400"; d="scan'208";a="195123508" Received: from chiahuil-mobl.amr.corp.intel.com (HELO pbossart-mobl3.amr.corp.intel.com) ([10.255.228.77]) by orsmga007.jf.intel.com with ESMTP; 14 Nov 2019 10:17:50 -0800 From: Pierre-Louis Bossart To: alsa-devel@alsa-project.org Cc: linux-kernel@vger.kernel.org, tiwai@suse.de, broonie@kernel.org, vkoul@kernel.org, gregkh@linuxfoundation.org, jank@cadence.com, srinivas.kandagatla@linaro.org, slawomir.blauciak@intel.com, Bard liao , Rander Wang , Ranjani Sridharan , Pierre-Louis Bossart , Sanyog Kale Subject: [PATCH v3 13/22] soundwire: bus: fix race condition with initialization_complete signaling Date: Thu, 14 Nov 2019 12:16:53 -0600 Message-Id: <20191114181702.22254-14-pierre-louis.bossart@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191114181702.22254-1-pierre-louis.bossart@linux.intel.com> References: <20191114181702.22254-1-pierre-louis.bossart@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 e34b5ed534b3..329f35a40649 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -648,6 +648,7 @@ 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) { dev_dbg(&slave->dev, @@ -1051,6 +1052,7 @@ 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 */ @@ -1096,6 +1098,8 @@ 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) @@ -1122,6 +1126,8 @@ 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, @@ -1140,6 +1146,8 @@ 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 76fdfbd8b50d..d2a952d9bd47 100644 --- a/drivers/soundwire/slave.c +++ b/drivers/soundwire/slave.c @@ -53,6 +53,7 @@ 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; -- 2.20.1