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=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 5E492C2D0DB for ; Wed, 29 Jan 2020 23:44:23 +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 C8CD1206F0 for ; Wed, 29 Jan 2020 23:44:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="Pyr7X6VS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C8CD1206F0 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 330A51657; Thu, 30 Jan 2020 00:43:31 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 330A51657 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1580341461; bh=1AZLP9aKm/4VjiGGnhXcqrrKxazfqnt27gR+1gTWOJQ=; h=To:References:From:Date:In-Reply-To:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=Pyr7X6VSLN3peqhL9nuVBYzfkZZ4YQkKCKiDYQiSxItoYfkhuIUqpy1JMv6iNbb0B qOph9yhWak8R1r+2NZTScfVuf6GhaMHFWVQ/zMLPjfNyy+i5Nfdzexx0DWcr7CHIup 6pd+iewnJOV6o/xFN+8jrIBxfufY+n9By7/HTBsM= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 98BB4F80122; Thu, 30 Jan 2020 00:43:30 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 2D09CF8021E; Thu, 30 Jan 2020 00:43:28 +0100 (CET) Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) (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 04427F80122 for ; Thu, 30 Jan 2020 00:43:23 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 04427F80122 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 29 Jan 2020 15:43:19 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,379,1574150400"; d="scan'208";a="252831298" Received: from kjhudson-mobl1.amr.corp.intel.com (HELO [10.254.70.93]) ([10.254.70.93]) by fmsmga004.fm.intel.com with ESMTP; 29 Jan 2020 15:43:20 -0800 To: sylvain.bertrand@gmail.com, alsa-devel@alsa-project.org References: <20200129232340.GA23769@freedom> From: Pierre-Louis Bossart Message-ID: Date: Wed, 29 Jan 2020 17:43:19 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200129232340.GA23769@freedom> Content-Language: en-US Subject: Re: [alsa-devel] no period wakeup support 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: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" > Nowadays, is this reasonable to consider disabling the period wakeup as default > instead of expecting period wakeup by default? I'd say yes - it's been nearly 10 years since this capability was added, and it's quite common across HDaudio, Chrome, Android plaforms. But considering this as a default doesn't mean it's available in 100% of the cases, you still you need to check that a) the driver is capable of disabling the period wakeup b) the driver is capable of providing a precise position outside of period elapsed events (usually marked with the INFO_BATCH capability). alsa-lib gives you the means to query both cases. Note that you also have the case where you cannot disable interrupts but can still use timer-based solutions (e.g. for USB audio). Hope this helps -Pierre _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel