pps: generators: Add PPS Generator TIO Driver

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 har

pps: generators: Add PPS Generator TIO Driver

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 <[email protected]>
Signed-off-by: Christopher Hall <[email protected]>
Co-developed-by: Pandith N <[email protected]>
Signed-off-by: Pandith N <[email protected]>
Co-developed-by: Thejesh Reddy T R <[email protected]>
Signed-off-by: Thejesh Reddy T R <[email protected]>
Signed-off-by: Lakshmi Sowjanya D <[email protected]>
Reviewed-by: Eddie Dong <[email protected]>
Reviewed-by: Andy Shevchenko <[email protected]>
Acked-by: Rodolfo Giometti <[email protected]>
Signed-off-by: Subramanian Mohan <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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drivers pps/generators: add dummy PPS generator

This dummy PPS generator can be used for debugging and documentation
purposes.

Signed-off-by: Rodolfo Giometti <[email protected]>
Link: https://

drivers pps/generators: add dummy PPS generator

This dummy PPS generator can be used for debugging and documentation
purposes.

Signed-off-by: Rodolfo Giometti <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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drivers pps: add PPS generators support

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

drivers pps: add PPS generators support

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 <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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treewide: Add SPDX license identifier - Makefile/Kconfig

Add SPDX license identifiers to all Make/Kconfig files which:

- Have no license information of any form

These files fall under the project

treewide: Add SPDX license identifier - Makefile/Kconfig

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 <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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drivers/pps: use surrounding "if PPS" to remove numerous dependency checks

Adding high-level "if PPS" makes lower-level dependency tests superfluous.

Link: http://lkml.kernel.org/r/alpine.LFD.2.20.

drivers/pps: use surrounding "if PPS" to remove numerous dependency checks

Adding high-level "if PPS" makes lower-level dependency tests superfluous.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Robert P. J. Day <[email protected]>
Acked-by: Rodolfo Giometti <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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drivers: pps: Make PPS into a menuconfig to ease disabling

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 o

drivers: pps: Make PPS into a menuconfig to ease disabling

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 <[email protected]>
Acked-by: Rodolfo Giometti <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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pps: make pps_gen_parport depend on BROKEN

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 b

pps: make pps_gen_parport depend on BROKEN

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 <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Cc: Rodolfo Giometti <[email protected]>
Cc: john stultz <[email protected]>
Cc: Ingo Molnar <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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pps: add parallel port PPS signal generator

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 co

pps: add parallel port PPS signal generator

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 <[email protected]>
Cc: Rodolfo Giometti <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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pps: add parallel port PPS signal generator

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 co

pps: add parallel port PPS signal generator

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.

[[email protected]: fix build]
Signed-off-by: Alexander Gordeev <[email protected]>
Acked-by: Rodolfo Giometti <[email protected]>
Cc: john stultz <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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