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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 5772BC43142 for ; Tue, 31 Jul 2018 13:56:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C56520894 for ; Tue, 31 Jul 2018 13:56:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C56520894 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732285AbeGaPhU (ORCPT ); Tue, 31 Jul 2018 11:37:20 -0400 Received: from mx2.suse.de ([195.135.220.15]:44640 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1732169AbeGaPhU (ORCPT ); Tue, 31 Jul 2018 11:37:20 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 98E92AFC4; Tue, 31 Jul 2018 13:56:52 +0000 (UTC) Date: Tue, 31 Jul 2018 15:56:52 +0200 Message-ID: From: Takashi Iwai To: Mark Brown Cc: "Agrawal, Akshu" , Pierre-Louis Bossart , "moderated list:SOUND - SOC LAYER / DYNAMIC AUDIO POWER MANAGEM..." , Alexander.Deucher@amd.com, djkurtz@chromium.org, Liam Girdwood , open list Subject: Re: [alsa-devel] [PATCH] ASoC: soc-pcm: Use delay set in pointer function In-Reply-To: <20180731135115.GD5719@sirena.org.uk> References: <20180730155030.GP5789@sirena.org.uk> <7a88c7b4-d31d-b044-bb8e-a866d49d1256@amd.com> <5b3249cb-6212-6a14-b644-7548cf0ad00c@amd.com> <20180731101943.GB5719@sirena.org.uk> <20180731131246.GC5719@sirena.org.uk> <20180731135115.GD5719@sirena.org.uk> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/26 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 31 Jul 2018 15:51:15 +0200, Mark Brown wrote: > > On Tue, Jul 31, 2018 at 03:29:35PM +0200, Takashi Iwai wrote: > > Mark Brown wrote: > > > > > > However since it's not supposed to be providing any DMA a CPU DAI really > > > > > shouldn't be doing this... > > > > > Well, if so, the CPU dai also cannot get the exact base delay > > > > corresponding to the reported position, either, no? > > > > It can know how much delay it's adding internally between its input and > > > output, which feeds into the overall delay experienced by the user. > > > But isn't it merely the additional delay that should be applied on top > > of the existing runtime->delay? > > Yes. I'm saying that if the CPU DAI thinks it can figure out the base > delay something is confused. Then basically Akshu's patch does the correct thing, I suppose. Takashi