From patchwork Thu Jul 26 11:42:36 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shreyas NC X-Patchwork-Id: 10545633 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 EC9AA14E0 for ; Thu, 26 Jul 2018 11:44:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DA4A9286AA for ; Thu, 26 Jul 2018 11:44:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CE7A02B086; Thu, 26 Jul 2018 11:44:57 +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 2ADF0286AA for ; Thu, 26 Jul 2018 11:44:57 +0000 (UTC) Received: from alsa0.perex.cz (localhost [127.0.0.1]) by alsa0.perex.cz (Postfix) with ESMTP id 6CF072677A9; Thu, 26 Jul 2018 13:44:41 +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 039B926779D; Thu, 26 Jul 2018 13:44:37 +0200 (CEST) Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by alsa0.perex.cz (Postfix) with ESMTP id E3D4926778A for ; Thu, 26 Jul 2018 13:44:35 +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 fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 26 Jul 2018 04:44:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,404,1526367600"; d="scan'208";a="243491189" Received: from snc-desk.iind.intel.com ([10.223.96.118]) by orsmga005.jf.intel.com with ESMTP; 26 Jul 2018 04:44:23 -0700 From: Shreyas NC To: alsa-devel@alsa-project.org Date: Thu, 26 Jul 2018 17:12:36 +0530 Message-Id: <1532605362-19282-5-git-send-email-shreyas.nc@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1532605362-19282-1-git-send-email-shreyas.nc@intel.com> References: <1532605362-19282-1-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 v7 04/10] 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 From: Sanyog Kale 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 29121aa..19482ee 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 ================================