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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * pps-ktimer.c -- kernel timer test client4 *5 * Copyright (C) 2005-2006 Rodolfo Giometti <giometti@linux.it>6 */7 8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt9 10#include <linux/kernel.h>11#include <linux/module.h>12#include <linux/init.h>13#include <linux/time.h>14#include <linux/timer.h>15#include <linux/pps_kernel.h>16 17/*18 * Global variables19 */20 21static struct pps_device *pps;22static struct timer_list ktimer;23 24/*25 * The kernel timer26 */27 28static void pps_ktimer_event(struct timer_list *unused)29{30 struct pps_event_time ts;31 32 /* First of all we get the time stamp... */33 pps_get_ts(&ts);34 35 pps_event(pps, &ts, PPS_CAPTUREASSERT, NULL);36 37 mod_timer(&ktimer, jiffies + HZ);38}39 40/*41 * The PPS info struct42 */43 44static struct pps_source_info pps_ktimer_info = {45 .name = "ktimer",46 .path = "",47 .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT |48 PPS_ECHOASSERT |49 PPS_CANWAIT | PPS_TSFMT_TSPEC,50 .owner = THIS_MODULE,51};52 53/*54 * Module staff55 */56 57static void __exit pps_ktimer_exit(void)58{59 dev_info(pps->dev, "ktimer PPS source unregistered\n");60 61 del_timer_sync(&ktimer);62 pps_unregister_source(pps);63}64 65static int __init pps_ktimer_init(void)66{67 pps = pps_register_source(&pps_ktimer_info,68 PPS_CAPTUREASSERT | PPS_OFFSETASSERT);69 if (IS_ERR(pps)) {70 pr_err("cannot register PPS source\n");71 return PTR_ERR(pps);72 }73 74 timer_setup(&ktimer, pps_ktimer_event, 0);75 mod_timer(&ktimer, jiffies + HZ);76 77 dev_info(pps->dev, "ktimer PPS source registered\n");78 79 return 0;80}81 82module_init(pps_ktimer_init);83module_exit(pps_ktimer_exit);84 85MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");86MODULE_DESCRIPTION("dummy PPS source by using a kernel timer (just for debug)");87MODULE_LICENSE("GPL");88