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 0570EC433F5 for ; Fri, 14 Jan 2022 04:37:09 +0000 (UTC) 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 784061F6A; Fri, 14 Jan 2022 05:36:17 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 784061F6A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1642135027; bh=I7EX1sgM295J7pPU5dDB3cslpOl7o8Z+Xe5IyDMJoLs=; h=Date:To:References:From:Subject:In-Reply-To:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=EhfBLo/jWdb3hYV+g85CQnOvYouCDP36gpqpOt83id1BC3Fr54nx4JlwE3xkALl6A 7A2PllcRvDkgwenuqKajnlBWVhoFOXQ8p/sQ21T3G9HLuqSC6K0PDslG5tDEKjEPW/ xa21X6XWxxhHQuVZN16ob4L37CQE5Dw58fTWrXIE= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id 0BAF2F8027C; Fri, 14 Jan 2022 05:36:17 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 1D6A5F80141; Fri, 14 Jan 2022 05:36:16 +0100 (CET) Received: from server1.nandakumar.co.in (nandakumar.co.in [198.100.152.31]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id 0DDC4F80141 for ; Fri, 14 Jan 2022 05:36:09 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz 0DDC4F80141 Authentication-Results: alsa1.perex.cz; dkim=pass (1024-bit key) header.d=nandakumar.co.in header.i=@nandakumar.co.in header.b="ZvGsHi0+" Received: from [192.168.100.185] (unknown [61.3.112.72]) by server1.nandakumar.co.in (Postfix) with ESMTPSA id A4B2BC816B; Fri, 14 Jan 2022 04:36:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=nandakumar.co.in; s=mail; t=1642134966; bh=I7EX1sgM295J7pPU5dDB3cslpOl7o8Z+Xe5IyDMJoLs=; h=Date:To:References:Cc:From:Subject:In-Reply-To:From; b=ZvGsHi0+iMzwoGnRT5ki4ctlnpRdWPLut6/PRrQPOAOJzOWp7Hob+Q3nV51Icnbpu kgWMxAK3Rs9yuG9F39e46PtEcWtQTTzfgTvXmH3k0nkNV6cA/rs0P1V/ja1q0yByB6 g7mVVFjsUilxkyKgUrhZe/bwov5rEWzM83nTokuY= Message-ID: Date: Fri, 14 Jan 2022 10:06:01 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.4.1 Content-Language: en-GB To: Geraldo Nascimento References: From: Nandakumar Edamana Subject: Re: Behringer UMC202HD issues and a partial solution In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit 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" Hi Geraldo, > Have you tried unloading the snd-usb-audio module and the reloading it > with implicit_fb=1 as in "modprobe -r snd-usb-audio" and "modprobe > snd-usb-audio implicit_fb=1" ? > > If not, try it. If it works and your playback issues are gone then > your device may just need a quirk. If it doesn't work we still > have dyndbg to go through. It works! Had to switch the devices and options back and forth in pavucontrol (sometimes needed even for the choppy playback), but it works. So why did my quirks didn't work? Maybe I gave the wrong numbers? Or the code was unreachable (I didn't put printk()s, sorry). I guessed the combos from `lsusb -v` output, and even tried the combos that didn't make any sense (because I didn't know what I was doing). Here's what I tried, one after another (added to playback_implicit_fb_quirks in /sound/usb/implicit.c): IMPLICIT_FB_GENERIC_DEV(0x1397, 0x0507), /* Didn't work */ IMPLICIT_FB_FIXED_DEV(0x1397, 0x0507, 0x84, 1), /* Interface 2 is actually Capture as per `cat /proc/asound/card1/stream0`,  * but "Implicit feedback Data" is found under that  * (Interface 1 has explicit Feedback), and a Scarlett quirk seemed to use  * a capture interface in playback_implicit_fb_quirks  * (I know that it's a capture interface from `lsusb` output posted by someone  * online)  */ /* Didn't work */ IMPLICIT_FB_FIXED_DEV(0x1397, 0x0507, 0x88, 2), /* Didn't work */ /* What am I doing with 0x08 ? */ IMPLICIT_FB_FIXED_DEV(0x1397, 0x0507, 0x08, 1), /* Didn't work */ /* Why BOTH? But what's FIXED at first? Didn't find any doc. */ IMPLICIT_FB_BOTH_DEV(0x1397, 0x0507, 0x84, 1), /* Didn't work */ IMPLICIT_FB_SKIP_DEV(0x1397, 0x0507), > Last but not least, please use a vanilla kernel for these tests. I built it using the source from kernel.org, not apt. But I've used oldconfig, and I think patches are being applied while installing the kernel (currently I'm using my daily driver installation for this). If it has to be more pure, I 'll try. BTW, do you have any distro to recommend that has a near-vanilla kernel for experiments like this? Another question: assuming a quirk gets added for this device, is there any chance that the quirk would break the experience for those who are already using the device (possibly a different revision, but the same ID [1]) without any issues? [1] https://h-node.org/soundcards/view/en/2228/Behringer-UMC202HD Thank you, -- Nandakumar Edamana https://nandakumar.org GPG Key: https://nandakumar.org/contact/gpgkey.asc GPG Key Fingerprint: BA6B 8FDE 644F F861 B638 3E2F 45D6 05FC 646A F75D