summaryrefslogtreecommitdiff
path: root/drivers/pps/generators/Kconfig
AgeCommit message (Collapse)AuthorFilesLines
2025-02-21pps: generators: Add PPS Generator TIO DriverSubramanian Mohan1-0/+16
The Intel Timed IO PPS generator driver outputs a PPS signal using dedicated hardware that is more accurate than software actuated PPS. The Timed IO hardware generates output events using the ART timer. The ART timer period varies based on platform type, but is less than 100 nanoseconds for all current platforms. Timed IO output accuracy is within 1 ART period. PPS output is enabled by writing '1' the 'enable' sysfs attribute. The driver uses hrtimers to schedule a wake-up 10 ms before each event (edge) target time. At wakeup, the driver converts the target time in terms of CLOCK_REALTIME to ART trigger time and writes this to the Timed IO hardware. The Timed IO hardware generates an event precisely at the requested system time without software involvement. Co-developed-by: Christopher Hall <christopher.s.hall@intel.com> Signed-off-by: Christopher Hall <christopher.s.hall@intel.com> Co-developed-by: Pandith N <pandith.n@intel.com> Signed-off-by: Pandith N <pandith.n@intel.com> Co-developed-by: Thejesh Reddy T R <thejesh.reddy.t.r@intel.com> Signed-off-by: Thejesh Reddy T R <thejesh.reddy.t.r@intel.com> Signed-off-by: Lakshmi Sowjanya D <lakshmi.sowjanya.d@intel.com> Reviewed-by: Eddie Dong <eddie.dong@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Subramanian Mohan <subramanian.mohan@intel.com> Link: https://lore.kernel.org/r/20250219040618.70962-3-subramanian.mohan@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-08drivers pps/generators: add dummy PPS generatorRodolfo Giometti1-0/+9
This dummy PPS generator can be used for debugging and documentation purposes. Signed-off-by: Rodolfo Giometti <giometti@enneenne.com> Link: https://lore.kernel.org/r/20241108073115.759039-3-giometti@enneenne.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-08drivers pps: add PPS generators supportRodolfo Giometti1-1/+12
Sometimes one needs to be able not only to catch PPS signals but to produce them also. For example, running a distributed simulation, which requires computers' clock to be synchronized very tightly. This patch adds PPS generators class in order to have a well-defined interface for these devices. Signed-off-by: Rodolfo Giometti <giometti@enneenne.com> Link: https://lore.kernel.org/r/20241108073115.759039-2-giometti@enneenne.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner1-0/+1
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-08drivers/pps: use surrounding "if PPS" to remove numerous dependency checksRobert P. J. Day1-2/+1
Adding high-level "if PPS" makes lower-level dependency tests superfluous. Link: http://lkml.kernel.org/r/alpine.LFD.2.20.1708261050500.8156@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>
2017-05-18drivers: pps: Make PPS into a menuconfig to ease disablingVincent Legoll1-1/+2
So that there's no need to get into the submenu to disable all related config entries. The BROKEN PPS_GENERATOR_PARPORT now also depends on PPS Signed-off-by: Vincent Legoll <vincent.legoll@gmail.com> Acked-by: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2011-03-04pps: make pps_gen_parport depend on BROKENThomas Gleixner1-1/+1
This driver causes hard lockups, when the active clock soure is jiffies. The reason is that it loops with interrupts disabled waiting for a timestamp to be reached by polling getnstimeofday(). Though with a jiffies clocksource, when that code runs on the same CPU which is responsible for updating jiffies, then we loop in circles for ever simply because the timer interrupt cannot update jiffies. So both UP and SMP can be affected. There is no easy fix for that problem so make it depend on BROKEN for now. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Gordeev <lasaine@lvk.cs.msu.su> Cc: Rodolfo Giometti <giometti@linux.it> Cc: john stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13pps: add parallel port PPS signal generatorAlexander Gordeev1-5/+1
Add PPS signal generator which utilizes STROBE pin of a parallel port to send PPS signals. It uses parport abstraction layer and hrtimers to precisely control the signal. Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Cc: 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: add parallel port PPS signal generatorAlexander Gordeev1-0/+17
Add PPS signal generator which utilizes STROBE pin of a parallel port to send PPS signals. It uses parport abstraction layer and hrtimers to precisely control the signal. [akpm@linux-foundation.org: fix build] Signed-off-by: Alexander Gordeev <lasaine@lvk.cs.msu.su> Acked-by: Rodolfo Giometti <giometti@linux.it> Cc: john stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>