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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 32C1EC4363A for ; Tue, 27 Oct 2020 07:28:36 +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 0348F22264 for ; Tue, 27 Oct 2020 07:28:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="gDTPg0Er" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0348F22264 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de 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 69653169A; Tue, 27 Oct 2020 08:27:42 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 69653169A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1603783712; bh=odbOx04f0qVekH6jM/DT4KH0KUqxyIVb067AsagqFYw=; h=Date:From:To:Subject:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=gDTPg0ErE4bZbM6LCKjHry05y7PK0TBqXv0SsrTPWvc+Jxn+rb3+EZdqSTIxe+7rk A53Rk4A8L0R6iQk1nghi+t6foG/rsqVFE62DebZzfOUYuQPZSMpjrsOWSn0U/Odjlm ynkZw7hunGut0phD+8BGyUawwbajK/jRFihCPMbY= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id D77EFF801D8; Tue, 27 Oct 2020 08:27:41 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 397E8F8020D; Tue, 27 Oct 2020 08:27:40 +0100 (CET) Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id CC61CF8019D for ; Tue, 27 Oct 2020 08:27:32 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz CC61CF8019D X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 15391ABA2; Tue, 27 Oct 2020 07:27:31 +0000 (UTC) Date: Tue, 27 Oct 2020 08:27:31 +0100 Message-ID: From: Takashi Iwai To: Keith Winstein Subject: Re: [PATCH] ALSA: usb-audio: Add implicit feedback quirk for Zoom UAC-2 In-Reply-To: <20201027071841.GA164525@trolley.csail.mit.edu> References: <20201026080143.GA145492@trolley.csail.mit.edu> <20201027071841.GA164525@trolley.csail.mit.edu> 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/25.3 (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 Cc: alsa-devel@alsa-project.org 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: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On Tue, 27 Oct 2020 08:18:41 +0100, Keith Winstein wrote: > > On Mon, Oct 26, 2020 at 02:52:28PM +0100, Takashi Iwai wrote: > > On Mon, 26 Oct 2020 09:01:43 +0100, > > Keith Winstein wrote: > > > > > > Here is the patch again without line-wrapping. > > > > Could you put the patch description in the patch itself? > > Basically I'm fine to merge this as is, just missing information for > > git. > > Sure, here you go: > > >From 51fac91fa3a5da656ca6a49ca6cc98be7664efd7 Mon Sep 17 00:00:00 2001 > From: Keith Winstein > Date: Sun, 25 Oct 2020 22:05:47 -0700 > Subject: [PATCH] ALSA: usb-audio: Add implicit feedback quirk for Zoom UAC-2 > > The Zoom UAC-2 USB audio interface provides an async playback endpoint ("1 OUT (ASYNC)") and > capture endpoint ("2 IN (ASYNC)"), both with 2-channel S32_LE in 44.1, 48, 88.2, 96, 176.4, > or 192 kilosamples/s. The device provides explicit feedback to adjust the host's playback > rate, but the feedback appears unstable and biased relative to the device's capture rate. > "alsaloop -t 1000" experiences playback underruns and tries to resample the captured audio > to match the varying playback rate. Forcing the kernel to use implicit feedback appears to > produce more stable results. This causes the host to transmit one playback sample for each > capture sample received. (Zoom North America has been notified of this change.) > > Signed-off-by: Keith Winstein > Tested-by: Keith Winstein Applied now. Thanks. Takashi