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2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 675 mass ave cambridge ma 02139 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 441 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-08drivers/pps: aesthetic tweaks to PPS-related contentRobert P. J. Day
Collection of aesthetic adjustments to various PPS-related files, directories and Documentation, some quite minor just for the sake of consistency, including: * Updated example of pps device tree node (courtesy Rodolfo G.) * "PPS-API" -> "PPS API" * "pps_source_info_s" -> "pps_source_info" * "ktimer driver" -> "pps-ktimer driver" * "ppstest /dev/pps0" -> "ppstest /dev/pps1" to match example * Add missing PPS-related entries to MAINTAINERS file * Other trivialities Link: http://lkml.kernel.org/r/alpine.LFD.2.20.1708261048220.8106@localhost.localdomain Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Acked-by: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-02time: Remove duplicated code in ktime_get_raw_and_real()Christopher S. Hall
The code in ktime_get_snapshot() is a superset of the code in ktime_get_raw_and_real() code. Further, ktime_get_raw_and_real() is called only by the PPS code, pps_get_ts(). Consolidate the pps_get_ts() code into a single function calling ktime_get_snapshot() and eliminate ktime_get_raw_and_real(). A side effect of this is that the raw and real results of pps_get_ts() correspond to exactly the same clock cycle. Previously these values represented separate reads of the system clock. Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: kevin.b.stanton@intel.com Cc: kevin.j.clarke@intel.com Cc: hpa@zytor.com Cc: jeffrey.t.kirsher@intel.com Cc: netdev@vger.kernel.org Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Christopher S. Hall <christopher.s.hall@intel.com> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-10-01ntp/pps: use y2038 safe types in pps_event_timeArnd Bergmann
The pps_event_time uses two 'timespec' structures internally, which suffer from the y2038 problem. The uses of this structure are fairly self-contained in the pps code, so this replaces them all at once. Unfortunately, this includes the sfc ethernet driver aside from the pps subsystem, so we change that one as well. Both touch the same data structure, and there probably is no good way to split the patch into smaller units. Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2015-10-01ntp/pps: replace getnstime_raw_and_real with 64-bit versionArnd Bergmann
There is exactly one caller of getnstime_raw_and_real in the kernel, which is the pps_get_ts function. This changes the caller and the implementation to work on timespec64 types rather than timespec, to avoid the time_t overflow on 32-bit architectures. For consistency with the other new functions (ktime_get_seconds, ktime_get_real_*, ...), I'm renaming the function to ktime_get_raw_and_real_ts64. We still need to convert from the internal 64-bit type to 32 bit types in the caller, but this conversion is now pushed out from getnstime_raw_and_real to pps_get_ts. A follow-up patch changes the remaining pps code to completely avoid the conversion. Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: David S. Miller <davem@davemloft.net> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-08-19PPS: convert class code to use dev_groupsGreg Kroah-Hartman
The dev_attrs field of struct class is going away soon, dev_groups should be used instead. This converts the pps class code to use the correct field. Cc: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-13pps: Add pps_lookup_dev() functionGeorge Spelvin
The PPS serial line discipline wants to attach a PPS device to a tty without changing the tty code to add a struct pps_device * pointer. Since the number of PPS devices in a typical system is generally very low (n=1 is by far the most common), it's practical to search the entire list of allocated pps devices. (We capture the timestamp before the lookup, so the timing isn't affected.) It is a bit ugly that this function, which is part of the in-kernel PPS API, has to be in pps.c as opposed to kapi,c, but that's not something that affects users. Signed-off-by: George Spelvin <linux@horizon.com> Acked-by: Rodolfo Giometti <giometti@enneenne.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-07pps/ptp: Allow PHC devices to adjust PPS events for known delayBen Hutchings
Initial version by Stuart Hodgson <smhodgson@solarflare.com> Some PHC device drivers may deliver PPS events with a significant and variable delay, but still be able to measure precisely what that delay is. Add a pps_sub_ts() function for subtracting a delay from the timestamp(s) in a PPS event, and a PTP event type (PTP_CLOCK_PPSUSR) for which the caller provides a complete PPS event. Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
2011-01-13pps: capture MONOTONIC_RAW timestamps as wellAlexander Gordeev
MONOTONIC_RAW clock timestamps are ideally suited for frequency calculation and also fit well into the original NTP hardpps design. Now phase and frequency can be adjusted separately: the former based on REALTIME clock and the latter based on MONOTONIC_RAW clock. A new function getnstime_raw_and_real is added to timekeeping subsystem to capture both timestamps at the same time and atomically. Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13pps: access pps device by direct pointerAlexander Gordeev
Using device index as a pointer needs some unnecessary work to be done every time the pointer is needed (in irq handler for example). Using a direct pointer is much more easy (and safe as well). Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: Rodolfo Giometti <giometti@linux.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13pps: unify timestamp gatheringAlexander Gordeev
Add a helper function to gather timestamps. This way clients don't have to duplicate it. Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: Rodolfo Giometti <giometti@linux.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13pps: fix race in PPS_FETCH handlerAlexander Gordeev
There was a race in PPS_FETCH ioctl handler when several processes want to obtain PPS data simultaneously using sleeping PPS_FETCH. They all sleep most of the time in the system call. With the old approach when the first process waiting on the pps queue is waken up it makes new system call right away and zeroes pps->go. So other processes continue to sleep. This is a clear race condition because of the global 'go' variable. With the new approach pps->last_ev holds some value increasing at each PPS event. PPS_FETCH ioctl handler saves current value to the local variable at the very beginning so it can safely check that there is a new event by just comparing both variables. Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: Rodolfo Giometti <giometti@linux.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13pps: trivial fixesAlexander Gordeev
Here are some very trivial fixes combined: - add macro definitions to protect header file from including several times - remove declaration for an unexistent array - fix typos Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: Rodolfo Giometti <giometti@linux.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-18LinuxPPS: core supportRodolfo Giometti
This patch adds the kernel side of the PPS support currently named "LinuxPPS". PPS means "pulse per second" and a PPS source is just a device which provides a high precision signal each second so that an application can use it to adjust system clock time. Common use is the combination of the NTPD as userland program with a GPS receiver as PPS source to obtain a wallclock-time with sub-millisecond synchronisation to UTC. To obtain this goal the userland programs shoud use the PPS API specification (RFC 2783 - Pulse-Per-Second API for UNIX-like Operating Systems, Version 1.0) which in part is implemented by this patch. It provides a set of chars devices, one per PPS source, which can be used to get the time signal. The RFC's functions can be implemented by accessing to these char devices. Signed-off-by: Rodolfo Giometti <giometti@linux.it> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg KH <greg@kroah.com> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Michael Kerrisk <mtk.manpages@googlemail.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>