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https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
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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>
38 lines
1.0 KiB
C
38 lines
1.0 KiB
C
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
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/*
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* PPS generator API header
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*
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* Copyright (C) 2024 Rodolfo Giometti <giometti@enneenne.com>
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*/
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#ifndef _PPS_GEN_H_
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#define _PPS_GEN_H_
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#include <linux/types.h>
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#include <linux/ioctl.h>
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/**
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* struct pps_gen_event - the PPS generator events
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* @event: the event type
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* @sequence: the event sequence number
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*
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* Userspace can get the last PPS generator event by using the
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* ioctl(pps_gen, PPS_GEN_FETCHEVENT, ...) syscall.
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* The sequence field can be used to save the last event ID, while in the
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* event field is stored the last event type. Currently known event is:
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*
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* PPS_GEN_EVENT_MISSEDPULSE : last pulse was not generated
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*/
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struct pps_gen_event {
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unsigned int event;
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unsigned int sequence;
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};
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#define PPS_GEN_EVENT_MISSEDPULSE 1
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#define PPS_GEN_SETENABLE _IOW('p', 0xb1, unsigned int *)
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#define PPS_GEN_USESYSTEMCLOCK _IOR('p', 0xb2, unsigned int *)
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#define PPS_GEN_FETCHEVENT _IOR('p', 0xb3, struct pps_gen_event *)
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#endif /* _PPS_GEN_H_ */
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