linux/drivers/pps/clients/pps-ktimer.c
YueHaibing 3b1ad360ac pps: using ERR_PTR instead of NULL while pps_register_source fails
pps_register_source() has keeps error codes in a local variable,
but it does not make use of the code. This patch let it return
the errcode in case of failure.

Suggested-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-27 10:05:36 +01:00

102 lines
2.4 KiB
C

/*
* pps-ktimer.c -- kernel timer test client
*
*
* Copyright (C) 2005-2006 Rodolfo Giometti <giometti@linux.it>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#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");