linux/linux-5.4.31/drivers/pps/clients/pps-ktimer.c

88 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pps-ktimer.c -- kernel timer test client
*
* Copyright (C) 2005-2006 Rodolfo Giometti <giometti@linux.it>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/timer.h>
#include <linux/pps_kernel.h>
/*
* Global variables
*/
static struct pps_device *pps;
static struct timer_list ktimer;
/*
* The kernel timer
*/
static void pps_ktimer_event(struct timer_list *unused)
{
struct pps_event_time ts;
/* First of all we get the time stamp... */
pps_get_ts(&ts);
pps_event(pps, &ts, PPS_CAPTUREASSERT, NULL);
mod_timer(&ktimer, jiffies + HZ);
}
/*
* The PPS info struct
*/
static struct pps_source_info pps_ktimer_info = {
.name = "ktimer",
.path = "",
.mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT |
PPS_ECHOASSERT |
PPS_CANWAIT | PPS_TSFMT_TSPEC,
.owner = THIS_MODULE,
};
/*
* Module staff
*/
static void __exit pps_ktimer_exit(void)
{
dev_info(pps->dev, "ktimer PPS source unregistered\n");
del_timer_sync(&ktimer);
pps_unregister_source(pps);
}
static int __init pps_ktimer_init(void)
{
pps = pps_register_source(&pps_ktimer_info,
PPS_CAPTUREASSERT | PPS_OFFSETASSERT);
if (IS_ERR(pps)) {
pr_err("cannot register PPS source\n");
return PTR_ERR(pps);
}
timer_setup(&ktimer, pps_ktimer_event, 0);
mod_timer(&ktimer, jiffies + HZ);
dev_info(pps->dev, "ktimer PPS source registered\n");
return 0;
}
module_init(pps_ktimer_init);
module_exit(pps_ktimer_exit);
MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("dummy PPS source by using a kernel timer (just for debug)");
MODULE_LICENSE("GPL");