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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 48E65C46475 for ; Thu, 25 Oct 2018 17:19:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0B8820834 for ; Thu, 25 Oct 2018 17:19:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Z2aHGGMp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D0B8820834 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com 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 S1727948AbeJZBwl (ORCPT ); Thu, 25 Oct 2018 21:52:41 -0400 Received: from mail-ed1-f66.google.com ([209.85.208.66]:39463 "EHLO mail-ed1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727401AbeJZBwl (ORCPT ); Thu, 25 Oct 2018 21:52:41 -0400 Received: by mail-ed1-f66.google.com with SMTP id e5-v6so9212221eds.6 for ; Thu, 25 Oct 2018 10:18:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=Aq+9ZbCS0gMvoTxw1ySnPSxot32FKp9r30wjIYrqhYI=; b=Z2aHGGMporiwu7F43YeagQi4RBstNzAo+Y1vf0Rn9h5zUYXnvz7qGSFVubQX/rwiLH OyMO0e/ywOPq478Es3ngrBm6W452zuYteUl3THEVUY1hBqtVZwXqkro6ul9PrII3ZTcX pmSwiGQgorwrbWNH/VNdyw13ufbra94ZznYFA1ckVzQOlpY9aoxLuvFpDK1UZFAO1SY6 3c1D/bGP8mlu0wf9P+DltM1xQ+pV7hZ6+nhoAdue0S/CSnebe53js2oY1lJwbsM7Dg88 cI1EsA8jnTCpLn4gxtAXr6tlquOlFavAVwc0MWurpyRo1qiWjrUQnz4gzJezup/EPVW4 4h+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Aq+9ZbCS0gMvoTxw1ySnPSxot32FKp9r30wjIYrqhYI=; b=Lhf1+RGi65XtH3cE1qsL1XlHh5DKWt5PlSSJGwG6YIguh5OqrUlqUc2ekoPpFV6DRI DpdTBsBEjBkb4IYKx0NzRtxeXQF0iwXO+J9/Oy9Sph/4gSMekGISk8uqXc6uSg+McuKs vYEQZYq6JcG0JDHMRiue5k0fyhFGIh3ATy4Zd1rM6T7P9Xi6UxB/KExbUlihxT1HJOjD P5TqXf0PioX11QT2IKITLyvwwS2nHGX62c+ImysqfGOIzU6C9WnEWFIQzcqa1i0Q19Jb Pws67zZf6bJD3/QjreoY7ijWFO58YhGjwt+EbEKnwDG44pAdm8iSkQ20r7R6PBiYVZR3 HndA== X-Gm-Message-State: AGRZ1gJVxSc0dg6JMY9XvKikayROjUniih6XPcqblbxTM0Sf7V+K0uO9 QvIy1NSuzhK90nFHc2UIzyU= X-Google-Smtp-Source: AJdET5fd4qEK+ooeDgrsofC4HN6A3Raf9kz6dRZ1pAnUH5VzfpNBha/U7sobkg/tzIeGgGkTyrSBEg== X-Received: by 2002:a50:c31b:: with SMTP id a27-v6mr87470edb.160.1540487938154; Thu, 25 Oct 2018 10:18:58 -0700 (PDT) Received: from [192.168.1.3] (x4e334e22.dyn.telefonica.de. [78.51.78.34]) by smtp.gmail.com with ESMTPSA id c18-v6sm1738972ejz.68.2018.10.25.10.18.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 25 Oct 2018 10:18:57 -0700 (PDT) Subject: Re: [alsa-devel] [PATCH v2] staging: bcm2835-audio: interpolate audio delay To: Takashi Iwai , Mike Brady Cc: stefan.wahren@i2se.com, devel@driverdev.osuosl.org, alsa-devel@alsa-project.org, f.fainelli@gmail.com, eric@anholt.net, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, julia.lawall@lip6.fr, linux-rpi-kernel@lists.infradead.org, nishka.dasgupta_ug18@ashoka.edu.in, linux-arm-kernel@lists.infradead.org References: <20181022191708.GA4659@ubuntu> <046aea96-e0d3-60f4-c61a-c26bb1b5c193@gmail.com> <9884c4f5-2343-e3a4-8d8b-dd2db404ef27@gmail.com> From: Kirill Marinushkin Message-ID: <5bc8295a-1e38-99b5-d54c-72e920600f83@gmail.com> Date: Thu, 25 Oct 2018 19:20:40 +0200 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Takashi, Mike, @Takashi On 10/25/18 09:37, Takashi Iwai wrote: > Well, in the API POV, it's nothing wrong to keep hwptr sticking while > updating only delay value. It implies that the hardware chip doesn't > provide the hwptr update. Thank you for the clarification. Modifying `runtime->delay` from the `pointer` function looked wrong for me. Now I understand the motivation and the use-case. I will be more careful when analyzing the code which doesn't fit my expectations. @Mike I was wrong. You can ignore my comments. Please don't take them personal: it's all about having high-quality code in kernel. Best Regards, Kirill