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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id F3E1EC54E76 for ; Thu, 5 Jan 2023 00:00:24 +0000 (UTC) Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id 9C461DC71; Thu, 5 Jan 2023 00:59:31 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 9C461DC71 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1672876821; bh=VUK+FoZ6RLONfaaQgaXBjEu8hvOPd1NckTmUOM0ZCK4=; h=Date:Subject:To:References:From:In-Reply-To:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: Cc:From; b=vIWSWxq2bLnzkcMflMYYl9B/qOtsZ2JG5ATvByl8gZuR1K8tFx1u05rUpvoTGCdd7 mplHl5Y6Ws2Bmjr1IGodQIwhOW1OGXz5gqRxmJpokbdQp7JWCrxmqUj+I42b02Upgw 2b0AQE+z/T+SiRvZbc4b4fsyE94azzHhjg94iwkY= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 6F189F80508; Thu, 5 Jan 2023 00:59:28 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id CC182F80240; Thu, 5 Jan 2023 00:59:25 +0100 (CET) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) (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 B6436F8024D for ; Thu, 5 Jan 2023 00:59:22 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz B6436F8024D Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key, unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=YAc1a+S0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1672876764; x=1704412764; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=VUK+FoZ6RLONfaaQgaXBjEu8hvOPd1NckTmUOM0ZCK4=; b=YAc1a+S0bFwto1iEdZP265pYadp00ANkOE5EE0/VrqmWREPNlIKDXjUD la0wGTv28xBkhU3vPGKz7tH3yt4IE5mU5Ups1zqiQNSihvndIbwhelaly +ZNsZinjC049HzMRfqJPiBGsff1q1kHgB3e97Y9chlxqcUmHcl3+s/Lpp kWyS65Q1XAz+E/k4ZEEMLEyNbBkGJTIPHeS7mfRpMASVPjMRYGjgKJ/Qd zqzUTWNg0m887a43MhNIGxntnImgD9qomdqlv8Ip9OA6i5wpTONK0YYnM ZLVXQAAfrNuuPH8Vnwh8FnaY/msQXkizAhB2IE62MqYCXxFWV8jYDdBeI A==; X-IronPort-AV: E=McAfee;i="6500,9779,10580"; a="323306093" X-IronPort-AV: E=Sophos;i="5.96,301,1665471600"; d="scan'208";a="323306093" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Jan 2023 15:58:52 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10580"; a="900745364" X-IronPort-AV: E=Sophos;i="5.96,301,1665471600"; d="scan'208";a="900745364" Received: from kvthalli-mobl1.amr.corp.intel.com (HELO [10.212.102.90]) ([10.212.102.90]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Jan 2023 15:58:50 -0800 Message-ID: <07443b54-2973-7990-e749-66dd7fb4e499@linux.intel.com> Date: Wed, 4 Jan 2023 17:51:19 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Firefox/102.0 Thunderbird/102.4.2 Subject: Re: [RFC PATCH 09/14] sound: usb: Introduce QC USB SND offloading support Content-Language: en-US To: Wesley Cheng , srinivas.kandagatla@linaro.org, mathias.nyman@intel.com, perex@perex.cz, broonie@kernel.org, lgirdwood@gmail.com, andersson@kernel.org, krzysztof.kozlowski+dt@linaro.org, gregkh@linuxfoundation.org, Thinh.Nguyen@synopsys.com, bgoswami@quicinc.com, tiwai@suse.com, robh+dt@kernel.org, agross@kernel.org References: <20221223233200.26089-1-quic_wcheng@quicinc.com> <20221223233200.26089-10-quic_wcheng@quicinc.com> From: Pierre-Louis Bossart In-Reply-To: <20221223233200.26089-10-quic_wcheng@quicinc.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.29 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: , Cc: devicetree@vger.kernel.org, alsa-devel@alsa-project.org, linux-arm-msm@vger.kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, quic_jackp@quicinc.com, quic_plai@quicinc.com Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On 12/23/22 17:31, Wesley Cheng wrote: > Several Qualcomm SoCs have a dedicated audio DSP, which has the ability to > support USB sound devices. This vendor driver will implement the required > handshaking with the DSP, in order to pass along required resources that > will be utilized by the DSP's USB SW. The communication channel used for > this handshaking will be using the QMI protocol. Required resources > include: > - Allocated secondary event ring address > - EP transfer ring address > - Interrupter number > > The above information will allow for the audio DSP to execute USB transfers > over the USB bus. It will also be able to support devices that have an > implicit feedback and sync endpoint as well. Offloading these data > transfers will allow the main/applications processor to enter lower CPU > power modes, and sustain a longer duration in those modes. Are you suggesting that the entire feedback loop be handled in the DSP? It's not clear what "Offloading these data transfers" refers to, the data part or the feedback path? Comments are almost inexistent in this patch so it's hard to figure out what it really does.