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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 5B547C433E0 for ; Wed, 27 May 2020 18:06:25 +0000 (UTC) Received: from shelob.surriel.com (shelob.surriel.com [96.67.55.147]) (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 3C90B2075A for ; Wed, 27 May 2020 18:06:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=axis.com header.i=@axis.com header.b="Vs08V3M1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3C90B2075A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=axis.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernelnewbies-bounces@kernelnewbies.org Received: from localhost ([::1] helo=shelob.surriel.com) by shelob.surriel.com with esmtp (Exim 4.93) (envelope-from ) id 1je0Pp-00040T-35; Wed, 27 May 2020 14:04:33 -0400 Received: from smtp2.axis.com ([195.60.68.18]) by shelob.surriel.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92.3) (envelope-from ) id 1jYr1e-0003LB-Di for kernelnewbies@kernelnewbies.org; Wed, 13 May 2020 09:02:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=axis.com; l=1662; q=dns/txt; s=axis-central1; t=1589374938; x=1620910938; h=date:from:to:cc:subject:in-reply-to:message-id: references:mime-version:content-transfer-encoding; bh=HmiGANTaWeCxvVIMvxry7eZiiySoeq97ejFPwewSvOQ=; b=Vs08V3M1e0N531UW/4wj1RR55uD4f43LLhRSiuDbxfo4QZ2NQaEj2xaJ Z+a+T26rzF6A/gHlVx8NDztxCwh8TGb0I6J0Rh2tAY2CQfDQSkGn0qaZL W2jpfevRiGXpRTSldcdEm9x3Jps3G3vPttUgzhkC+4mLnx1QpJjoh+ubU PUPUOpFNqgP212M94fgJwYJ2xYhmqYtC5H4s9z3OsK1tMVWqxW+u+CNsq wstnXQtqxUw1OoispjMPEc40MAG152oDXxIigDia14GHmvy0Qgj0NtecW 7rAQGyPOlc7/37OwJUqGtknRaNooAFWiEN2MWWuM3zaZO4k69YtnfrCCp Q==; IronPort-SDR: H28L571fwiwBqZmIUHb+UKInMxA0uXG+HaVBs+hqX/lnsjq8kqQfRwMsZeS1yHspWEBbF7B2sF 7LjZLd5yi4chd4OUi9ceabe6oTqb+DnRfW7Dt2ZX3w/p5Fh8pLfiEURcoCn9VOtJSfUW6rnPs0 tqtdFduthvkMMD24ZurRw5rrv1zClv3k1Gv74pG9yQzL5d30cMsSnwn76x+o81ZGnj0eaYCfXf RO3pR8NzT6g1hzUpFumT87ibfULw5jE+NWThdQjSogXUy1MuQ4P+NEGxQRsKuvuBxbCuuUdCTO R8I= X-IronPort-AV: E=Sophos;i="5.73,387,1583190000"; d="scan'208";a="8445975" Date: Wed, 13 May 2020 15:02:06 +0200 From: Ricard Wanderlof X-X-Sender: ricardw@lnxricardw1.se.axis.com To: Greg KH Subject: Re: sound over USB In-Reply-To: <20200512165359.GA702234@kroah.com> Message-ID: References: <20200512165359.GA702234@kroah.com> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 X-Originating-IP: [10.0.5.60] X-ClientProxiedBy: XBOX01.axis.com (10.0.5.15) To XBOX03.axis.com (10.0.5.17) X-Mailman-Approved-At: Wed, 27 May 2020 14:04:18 -0400 Cc: "alsa-devel@alsa-project.org" , "linux-usb@vger.kernel.org" , Subhashini Rao Beerisetty , kernelnewbies X-BeenThere: kernelnewbies@kernelnewbies.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: quoted-printable Errors-To: kernelnewbies-bounces@kernelnewbies.org On Tue, 12 May 2020, Greg KH wrote: > On Tue, May 12, 2020 at 10:13:10PM +0530, Subhashini Rao Beerisetty wrote: > > ... > >=A0 [116677.281756] usbcore: registered new interface driver snd-usb-aud= io > > > >=A0 The following nodes are present in the /dev/snd > > > > $ ls -l /dev/snd/ > > > > total 0 > > > > drwxr-xr-x 2 root root=A0=A0=A0=A0=A0=A0 60 May 12 11:32 by-id > > > > drwxr-xr-x 2 root root=A0=A0=A0=A0=A0=A0 60 May 12 11:32 by-path > > > > crw-rw---- 1 root audio 116,=A0 2 May 12 11:32 controlC1 > > > > crw-rw---- 1 root audio 116,=A0 4 May 12 11:32 pcmC1D0c > > > > crw-rw---- 1 root audio 116,=A0 3 May 12 11:32 pcmC1D0p > > > > crw-rw---- 1 root audio 116,=A0 1 May 12 11:32 seq > > > > crw-rw---- 1 root audio 116, 33 May 12 11:32 timer > > > > > > > > What are all these devices present in /dev/snd > > > > How do I use it for playing and recording an audio? > > > > Basically first I want to gain knowledge on set of test cases I can > > run on ALSA and then learn ALSA kernel modules stuff including > > snd_usb_audio mdule. > > > > So please guide me by providing related documentation/Steps. > = > ALSA should "just work" with this device, no need to do anything to the > kernel driver.=A0 Does it not work properly for you as-is? To clarify (if it's not too obvious): Normally these devices are never = accessed directly by programs, instead, there is a userspace library = called alsa-lib which provides a userspace API and then handles the = communication with the kernel devices. /Ricard -- = Ricard Wolf Wanderlof ricardw(at)axis.com Axis Communications AB, Lund, Sweden www.axis.com Phone +46 46 272 2016 Fax +46 46 13 61 30 _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies