From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v3] Add support for driver cross-timestamp to PTP_SYS_OFFSET ioctl Date: Thu, 09 Jul 2015 15:01:10 -0700 (PDT) Message-ID: <20150709.150110.1865960968554925450.davem@davemloft.net> References: <1436388401-32168-1-git-send-email-christopher.s.hall@intel.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: richardcochran@gmail.com, tglx@linutronix.de, john.stultz@linaro.org, john.ronciak@intel.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org To: christopher.s.hall@intel.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:45902 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752545AbbGIWBL (ORCPT ); Thu, 9 Jul 2015 18:01:11 -0400 In-Reply-To: <1436388401-32168-1-git-send-email-christopher.s.hall@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Christopher Hall Date: Wed, 8 Jul 2015 13:46:41 -0700 > This patch allows system and device time ("cross-timestamp") to be > performed by the driver. Currently, the cross-timestamping is performed > in the PTP_SYS_OFFSET ioctl. The PTP clock driver reads gettimeofday() > and the gettime64() callback provided by the driver. The cross-timestamp > is best effort where the latency between the capture of system time > (getnstimeofday()) and the device time (driver callback) may be > significant. Please resubmit this once there is an actual user of this new facility, not beforehand. Thank you.