Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752670Ab1CKNjH (ORCPT ); Fri, 11 Mar 2011 08:39:07 -0500 Received: from mailout-de.gmx.net ([213.165.64.23]:37308 "HELO mailout-de.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750735Ab1CKNjC (ORCPT ); Fri, 11 Mar 2011 08:39:02 -0500 X-Authenticated: #911537 X-Provags-ID: V01U2FsdGVkX19xi0kKJcFxpxqdI9T65/inmsSKimSx3YsEUH8Eat F4d1fa1kSO89Rk Date: Fri, 11 Mar 2011 14:38:52 +0100 From: torbenh To: Christian Riesch Cc: Richard Cochran , john stultz , "linux-kernel@vger.kernel.org" , Richard Cochran , "tglx@linutronix.de" Subject: Re: [PATCH 2/3] ptp: add a software clock based on clock_monotonic_raw Message-ID: <20110311133852.GB5553@siel.b> Mail-Followup-To: Christian Riesch , Richard Cochran , john stultz , "linux-kernel@vger.kernel.org" , Richard Cochran , "tglx@linutronix.de" References: <1299173174-348-1-git-send-email-torbenh@gmx.de> <1299173174-348-3-git-send-email-torbenh@gmx.de> <1299180844.28285.111.camel@work-vm> <20110304064639.GD3824@riccoc20.at.omicron.at> <1299355687.28285.130.camel@work-vm> <20110306132834.GA11790@riccoc20.at.omicron.at> <20110311111321.GA5553@siel.b> <95DC1AA8EC908B48939B72CF375AA5E3011C9E20A4@alice.at.omicron.at> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <95DC1AA8EC908B48939B72CF375AA5E3011C9E20A4@alice.at.omicron.at> User-Agent: Mutt/1.5.20 (2009-06-14) X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1602 Lines: 45 On Fri, Mar 11, 2011 at 12:37:57PM +0100, Christian Riesch wrote: > Torben, > > On Friday, March 11, 2011 12:13, torbenh wrote: > >On the audio lists, we have a guy now claiming that software ptp would > >confuse the whole h/w ptp infrastructure. His main agenda seems to be to > >prevent a software only ptp/avb implementatation. > > could you please post a link to that discussion? duncan started somewhat like this: http://article.gmane.org/gmane.comp.audio.jackit/23606 http://article.gmane.org/gmane.comp.audio.jackit/23612 then it seems that he somehow turned his head: http://www.mail-archive.com/linux-audio-dev@lists.linuxaudio.org/msg11765.html maybe we have a communication problem, with the definition of "play" i only want to be able to generate an RTP stream on my computer. the actual conversion from packets to analog signal would be happening on a networked soundcard. the goal is to achieve low latency in the range of 2-3ms ... maybe he interprets playing the rtp stream, as converting the rtp packets to analog audio. this obviously wouldnt work with software ptp, because we would need nanoseconds accuracy of the clock. but to just create an rtp stream, where a 2ms buffer doesnt underflow, just requires a clock accuracy of 500us. all in all this discussion might be a bit confusing. > Thanks, > Christian -- torben Hohn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/