Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756729Ab0LPP6P (ORCPT ); Thu, 16 Dec 2010 10:58:15 -0500 Received: from 81-174-11-161.staticnet.ngi.it ([81.174.11.161]:42104 "EHLO mail.enneenne.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1756160Ab0LPP6O (ORCPT ); Thu, 16 Dec 2010 10:58:14 -0500 Date: Thu, 16 Dec 2010 16:58:10 +0100 From: Rodolfo Giometti To: Alexander Gordeev Cc: linux-kernel@vger.kernel.org, "Nikita V. Youshchenko" , linuxpps@ml.enneenne.com, Andrew Morton Message-ID: <20101216155810.GG10333@enneenne.com> Mail-Followup-To: Alexander Gordeev , linux-kernel@vger.kernel.org, "Nikita V. Youshchenko" , linuxpps@ml.enneenne.com, Andrew Morton References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: GNU/Linux Device Drivers, Embedded Systems and Courses X-PGP-Key: gpg --keyserver keyserver.linux.it --recv-keys D25A5633 User-Agent: Mutt/1.5.20 (2009-06-14) X-SA-Exim-Connect-IP: 192.168.32.37 X-SA-Exim-Mail-From: giometti@enneenne.com Subject: Re: [PATCHv5 16/17] pps: add parallel port PPS client X-SA-Exim-Version: 4.2.1 (built Wed, 25 Jun 2008 17:14:11 +0000) X-SA-Exim-Scanned: Yes (on mail.enneenne.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1406 Lines: 28 On Wed, Nov 24, 2010 at 07:15:54PM +0300, Alexander Gordeev wrote: > Add parallel port PPS client. It uses a standard method for capturing > timestamps for assert edge transitions: getting a timestamp soon after > an interrupt has happened. This is not a very precise source of time > information due to interrupt handling delays. However, timestamps for > clear edge transitions are much more precise because the interrupt > handler continuously polls hardware port until the transition is done. > Hardware port operations require only about 1us so the maximum error > should not exceed this value. This was my primary goal when developing > this client. > Clear edge capture could be disabled using clear_wait parameter. > > Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti -- GNU/Linux Solutions e-mail: giometti@enneenne.com Linux Device Driver giometti@linux.it Embedded Systems phone: +39 349 2432127 UNIX programming skype: rodolfo.giometti Freelance ICT Italia - Consulente ICT Italia - www.consulenti-ict.it -- 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/