From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932316AbcFNS0W (ORCPT ); Tue, 14 Jun 2016 14:26:22 -0400 Received: from mail-wm0-f68.google.com ([74.125.82.68]:33306 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752618AbcFNS0V (ORCPT ); Tue, 14 Jun 2016 14:26:21 -0400 Date: Tue, 14 Jun 2016 20:26:15 +0200 From: Richard Cochran To: Henrik Austad Cc: linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, alsa-devel@vger.kernel.org, netdev@vger.kernel.org, Arnd Bergmann Subject: Re: [very-RFC 0/8] TSN driver for the kernel Message-ID: <20160614182615.GA2741@netboy> References: <1465686096-22156-1-git-send-email-henrik@austad.us> <20160613114713.GA9544@localhost.localdomain> <20160613130059.GA20320@sisyphus.home.austad.us> <20160613193208.GA2441@netboy> <20160614093000.GB21689@sisyphus.home.austad.us> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160614093000.GB21689@sisyphus.home.austad.us> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 14, 2016 at 11:30:00AM +0200, Henrik Austad wrote: > So loop data from kernel -> userspace -> kernelspace and finally back to > userspace and the media application? Huh? I wonder where you got that idea. Let me show an example of what I mean. void listener() { int in = socket(); int out = open("/dev/dsp"); char buf[]; while (1) { recv(in, buf, packetsize); write(out, buf + offset, datasize); } } See? > Yes, I know some audio apps "use networking", I can stream netradio, I can > use jack to connect devices using RTP and probably a whole lot of other > applications do similar things. However, AVB is more about using the > network as a virtual sound-card. That is news to me. I don't recall ever having seen AVB described like that before. > For the media application, it should not > have to care if the device it is using is a soudncard inside the box or a > set of AVB-capable speakers somewhere on the network. So you would like a remote listener to appear in the system as a local PCM audio sink? And a remote talker would be like a local media URL? Sounds unworkable to me, but even if you were to implement it, the logic would surely belong in alsa-lib and not in the kernel. Behind the enulated device, the library would run a loop like the example, above. In any case, your patches don't implement that sort of thing at all, do they? Thanks, Richard