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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-08-14 06:22:34 +02:00
Thomas Gleixner
fe1159fe49
There is no reason to use the more complex ktime_get_snapshot() for retrieving CLOCK_REALTIME. Just use ktime_get_real_ts64(), which avoids the extra timespec64 conversion as a bonus. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@kernel.org> Tested-by: Arthur Kiyanovski <akiyano@amazon.com> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Acked-by: Rodolfo Giometti <giometti@enneenne.com> Link: https://patch.msgid.link/20260529195557.074439049@kernel.org
93 lines
1.7 KiB
C
93 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* PPS dummy generator
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*
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* Copyright (C) 2024 Rodolfo Giometti <giometti@enneenne.com>
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/time.h>
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#include <linux/timer.h>
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#include <linux/random.h>
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#include <linux/pps_gen_kernel.h>
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static struct pps_gen_device *pps_gen;
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static struct timer_list ktimer;
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static unsigned int get_random_delay(void)
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{
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unsigned int delay = get_random_u8() & 0x0f;
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return (delay + 1) * HZ;
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}
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/*
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* The kernel timer
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*/
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static void pps_gen_ktimer_event(struct timer_list *unused)
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{
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pps_gen_event(pps_gen, PPS_GEN_EVENT_MISSEDPULSE, NULL);
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}
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/*
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* PPS Generator methods
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*/
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static int pps_gen_dummy_get_time(struct pps_gen_device *pps_gen,
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struct timespec64 *time)
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{
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ktime_get_real_ts64(time);
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return 0;
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}
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static int pps_gen_dummy_enable(struct pps_gen_device *pps_gen, bool enable)
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{
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if (enable)
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mod_timer(&ktimer, jiffies + get_random_delay());
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else
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timer_delete_sync(&ktimer);
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return 0;
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}
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/*
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* The PPS info struct
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*/
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static const struct pps_gen_source_info pps_gen_dummy_info = {
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.use_system_clock = true,
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.get_time = pps_gen_dummy_get_time,
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.enable = pps_gen_dummy_enable,
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};
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/*
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* Module staff
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*/
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static void __exit pps_gen_dummy_exit(void)
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{
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timer_delete_sync(&ktimer);
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pps_gen_unregister_source(pps_gen);
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}
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static int __init pps_gen_dummy_init(void)
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{
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pps_gen = pps_gen_register_source(&pps_gen_dummy_info);
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if (IS_ERR(pps_gen))
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return PTR_ERR(pps_gen);
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timer_setup(&ktimer, pps_gen_ktimer_event, 0);
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return 0;
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}
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module_init(pps_gen_dummy_init);
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module_exit(pps_gen_dummy_exit);
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MODULE_AUTHOR("Rodolfo Giometti <giometti@enneenne.com>");
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MODULE_DESCRIPTION("LinuxPPS dummy generator");
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MODULE_LICENSE("GPL");
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