From: Richard Cochran <richardcochran@gmail.com>
To: <netdev@vger.kernel.org>
Cc: David Miller <davem@davemloft.net>,
Jacob Keller <jacob.e.keller@intel.com>,
John Stultz <john.stultz@linaro.org>,
Miroslav Lichvar <mlichvar@redhat.com>
Subject: [PATCH RFC net-next 0/1] ptp: add pseudo pps ioctl
Date: Thu, 27 Sep 2012 20:12:15 +0200 [thread overview]
Message-ID: <cover.1348768886.git.richardcochran@gmail.com> (raw)
This patch adds a kind of "poor man's PPS" for use with those PHC
drivers which do not support a true PPS. Using this ioctl, user space
can estimate the system-phc offset and tune one of the clocks as
desired.
This patch has been tested on both the Intel igb (PCIe card) and the
National Semiconductor phyter (PHY via MDIO bus), and the results seem
quite promising.
This patch avoids the "timecompare" code on purpose, since experiments
have shown that code to be quite brittle, having been tuned to only
one specific kind of hardware.
Thanks,
Richard
Richard Cochran (1):
ptp: add an ioctl to compare PHC time with system time
drivers/ptp/ptp_chardev.c | 32 ++++++++++++++++++++++++++++++++
include/linux/ptp_clock.h | 14 ++++++++++++++
2 files changed, 46 insertions(+), 0 deletions(-)
--
1.7.2.5
next reply other threads:[~2012-09-27 18:12 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-27 18:12 Richard Cochran [this message]
2012-09-27 18:12 ` [PATCH RFC net-next 1/1] ptp: add an ioctl to compare PHC time with system time Richard Cochran
2012-09-28 7:53 ` Miroslav Lichvar
2012-09-28 8:26 ` Richard Cochran
2012-09-28 8:50 ` Miroslav Lichvar
2012-10-01 22:33 ` Keller, Jacob E
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