From patchwork Mon Jul 16 18:47:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sanyog Kale X-Patchwork-Id: 10527585 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 727A7600D0 for ; Mon, 16 Jul 2018 18:46:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 46F2128B59 for ; Mon, 16 Jul 2018 18:46:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 39D0728BF6; Mon, 16 Jul 2018 18:46:56 +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 6AC6628B59 for ; Mon, 16 Jul 2018 18:46:55 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id C14A52676FE; Mon, 16 Jul 2018 20:46:53 +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 0990226772E; Mon, 16 Jul 2018 20:46:51 +0200 (CEST) Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by alsa0.perex.cz (Postfix) with ESMTP id 75D202676FE for ; Mon, 16 Jul 2018 20:46:48 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Jul 2018 11:46:48 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,362,1526367600"; d="scan'208";a="240748028" Received: from buildpc-hp-z230.iind.intel.com ([10.223.84.34]) by orsmga005.jf.intel.com with ESMTP; 16 Jul 2018 11:46:45 -0700 From: Sanyog Kale To: alsa-devel@alsa-project.org Date: Tue, 17 Jul 2018 00:17:04 +0530 Message-Id: <20180716184713.13356-2-sanyog.r.kale@intel.com> X-Mailer: git-send-email 2.13.0 In-Reply-To: <20180716184713.13356-1-sanyog.r.kale@intel.com> References: <20180716184713.13356-1-sanyog.r.kale@intel.com> Cc: patches.audio@intel.com, gregkh@linuxfoundation.org, pierre-louis.bossart@linux.intel.com, vkoul@kernel.org, shreyas.nc@intel.com, sanyog.r.kale@intel.com Subject: [alsa-devel] [PATCH v6 01/10] Documentation: soundwire: Add documentation for multi link 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 Add example and documentation to describe multi link streams Signed-off-by: Pierre-Louis Bossart Signed-off-by: Sanyog Kale Signed-off-by: Vinod Koul Signed-off-by: Shreyas NC --- Documentation/driver-api/soundwire/stream.rst | 28 +++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/Documentation/driver-api/soundwire/stream.rst b/Documentation/driver-api/soundwire/stream.rst index 29121aa55fb9..19482eedc3bf 100644 --- a/Documentation/driver-api/soundwire/stream.rst +++ b/Documentation/driver-api/soundwire/stream.rst @@ -101,6 +101,34 @@ interface. :: +--------------------+ | | +----------------+ +Example 5: Stereo Stream with L and R channel is rendered by 2 Masters, each +rendering one channel, and is received by two different Slaves, each +receiving one channel. Both Masters and both Slaves are using single port. :: + + +---------------+ Clock Signal +---------------+ + | Master +----------------------------------+ Slave | + | Interface | | Interface | + | 1 | | 1 | + | | Data Signal | | + | L +----------------------------------+ L | + | (Data) | Data Direction | (Data) | + +---------------+ +-----------------------> +---------------+ + + +---------------+ Clock Signal +---------------+ + | Master +----------------------------------+ Slave | + | Interface | | Interface | + | 2 | | 2 | + | | Data Signal | | + | R +----------------------------------+ R | + | (Data) | Data Direction | (Data) | + +---------------+ +-----------------------> +---------------+ + +Note: In multi-link cases like above, to lock, one would acquire a global +lock and then go on locking bus instances. But, 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. + SoundWire Stream Management flow ================================