From patchwork Fri Jul 27 09:14:13 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shreyas NC X-Patchwork-Id: 10546787 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BCD0A174A for ; Fri, 27 Jul 2018 09:15:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ABA2F2B724 for ; Fri, 27 Jul 2018 09:15:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9FEDE2B74D; Fri, 27 Jul 2018 09:15:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DEE5E2B724 for ; Fri, 27 Jul 2018 09:15:19 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id 4F0242677BB; Fri, 27 Jul 2018 11:14:51 +0200 (CEST) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa0.perex.cz (Postfix, from userid 1000) id 13BA92677C6; Fri, 27 Jul 2018 11:14:49 +0200 (CEST) Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by alsa0.perex.cz (Postfix) with ESMTP id 937842677BB for ; Fri, 27 Jul 2018 11:14:45 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 27 Jul 2018 02:14:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,408,1526367600"; d="scan'208";a="219570705" Received: from snc-desk.iind.intel.com ([10.223.96.118]) by orsmga004.jf.intel.com with ESMTP; 27 Jul 2018 02:14:43 -0700 From: Shreyas NC To: alsa-devel@alsa-project.org Date: Fri, 27 Jul 2018 14:44:13 +0530 Message-Id: <1532682857-604-7-git-send-email-shreyas.nc@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1532682857-604-1-git-send-email-shreyas.nc@intel.com> References: <1532682857-604-1-git-send-email-shreyas.nc@intel.com> Cc: patches.audio@intel.com, gregkh@linuxfoundation.org, pierre-louis.bossart@linux.intel.com, vkoul@kernel.org, Shreyas NC , sanyog.r.kale@intel.com Subject: [alsa-devel] [PATCH v8 06/10] soundwire: Add support to lock across bus instances X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.14 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: , MIME-Version: 1.0 Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org X-Virus-Scanned: ClamAV using ClamSMTP From: Sanyog Kale Currently, the stream concept is limited to single Master and one or more Codecs. This patch extends the concept to support multiple Master(s) sharing the same reference clock and synchronized in the hardware. Modify sdw_stream_runtime to support a list of sdw_master_runtime for the same. The existing reference to a single m_rt is removed in the next patch. Typically to lock, one would acquire a global lock and then lock bus instances. In this case, the caller framework(ASoC DPCM) guarantees that stream operations on a card are always serialized. So, there is no race condition and hence no need for global lock. Bus lock(s) are acquired to reconfigure the bus while the stream is set-up. So, we add sdw_acquire_bus_lock()/sdw_release_bus_lock() APIs which are used only to reconfigure the bus. Signed-off-by: Sanyog Kale Signed-off-by: Vinod Koul Signed-off-by: Shreyas NC --- drivers/soundwire/bus.h | 2 ++ drivers/soundwire/stream.c | 43 +++++++++++++++++++++++++++++++++++++++++++ include/linux/soundwire/sdw.h | 4 ++++ 3 files changed, 49 insertions(+) diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index 3b15c4e..b6cfbdf 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -99,6 +99,7 @@ struct sdw_slave_runtime { * this stream, can be zero. * @slave_rt_list: Slave runtime list * @port_list: List of Master Ports configured for this stream, can be zero. + * @stream_node: sdw_stream_runtime master_list node * @bus_node: sdw_bus m_rt_list node */ struct sdw_master_runtime { @@ -108,6 +109,7 @@ struct sdw_master_runtime { unsigned int ch_count; struct list_head slave_rt_list; struct list_head port_list; + struct list_head stream_node; struct list_head bus_node; }; diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c index 28d4147..c6e497d 100644 --- a/drivers/soundwire/stream.c +++ b/drivers/soundwire/stream.c @@ -747,6 +747,7 @@ struct sdw_stream_runtime *sdw_alloc_stream(char *stream_name) return NULL; stream->name = stream_name; + INIT_LIST_HEAD(&stream->master_list); stream->state = SDW_STREAM_ALLOCATED; return stream; @@ -1245,6 +1246,48 @@ struct sdw_dpn_prop *sdw_get_slave_dpn_prop(struct sdw_slave *slave, return NULL; } +/** + * sdw_acquire_bus_lock: Acquire bus lock for all Master runtime(s) + * + * @stream: SoundWire stream + * + * Acquire bus_lock for each of the master runtime(m_rt) part of this + * stream to reconfigure the bus. + * NOTE: This function is called from SoundWire stream ops and is + * expected that a global lock is held before acquiring bus_lock. + */ +static void sdw_acquire_bus_lock(struct sdw_stream_runtime *stream) +{ + struct sdw_master_runtime *m_rt = NULL; + struct sdw_bus *bus = NULL; + + /* Iterate for all Master(s) in Master list */ + list_for_each_entry(m_rt, &stream->master_list, stream_node) { + bus = m_rt->bus; + + mutex_lock(&bus->bus_lock); + } +} + +/** + * sdw_release_bus_lock: Release bus lock for all Master runtime(s) + * + * @stream: SoundWire stream + * + * Release the previously held bus_lock after reconfiguring the bus. + */ +static void sdw_release_bus_lock(struct sdw_stream_runtime *stream) +{ + struct sdw_master_runtime *m_rt = NULL; + struct sdw_bus *bus = NULL; + + /* Iterate for all Master(s) in Master list */ + list_for_each_entry_reverse(m_rt, &stream->master_list, stream_node) { + bus = m_rt->bus; + mutex_unlock(&bus->bus_lock); + } +} + static int _sdw_prepare_stream(struct sdw_stream_runtime *stream) { struct sdw_master_runtime *m_rt = stream->m_rt; diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 962971e..ccd8dcdf 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -769,6 +769,9 @@ struct sdw_stream_params { * @state: Current state of the stream * @type: Stream type PCM or PDM * @m_rt: Master runtime + * @master_list: List of Master runtime(s) in this stream. + * master_list can contain only one m_rt per Master instance + * for a stream */ struct sdw_stream_runtime { char *name; @@ -776,6 +779,7 @@ struct sdw_stream_runtime { enum sdw_stream_state state; enum sdw_stream_type type; struct sdw_master_runtime *m_rt; + struct list_head master_list; }; struct sdw_stream_runtime *sdw_alloc_stream(char *stream_name);