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author | Rodolfo Giometti <giometti@linux.it> | 2010-03-10 15:23:45 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-03-12 15:52:43 -0800 |
commit | 697fb85fcf21b5229a3072440222d14b05ef2abe (patch) | |
tree | 9a40e480634584c3212a37d63b6e2eea7fa8f45d /drivers/pps/clients/pps-ktimer.c | |
parent | 51e7364ef281e540371f084008732b13292622f0 (diff) | |
download | linux-697fb85fcf21b5229a3072440222d14b05ef2abe.tar.gz linux-697fb85fcf21b5229a3072440222d14b05ef2abe.tar.bz2 linux-697fb85fcf21b5229a3072440222d14b05ef2abe.zip |
pps: LinuxPPS clients support
Each PPS source can be registered/deregistered into the system by using
special modules called "clients". They simply define the PPS sources'
attributes and implement the time signal registration mechanism.
This patch adds a special directory for such clients and adds a dummy
client that can be useful to test system integrity on real systems.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Rodolfo Giometti <giometti@linux.it>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg KH <greg@kroah.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Alexander Gordeev <lasaine@lvk.cs.msu.su>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/pps/clients/pps-ktimer.c')
-rw-r--r-- | drivers/pps/clients/pps-ktimer.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/drivers/pps/clients/pps-ktimer.c b/drivers/pps/clients/pps-ktimer.c new file mode 100644 index 000000000000..e7ef5b8186d0 --- /dev/null +++ b/drivers/pps/clients/pps-ktimer.c @@ -0,0 +1,123 @@ +/* + * 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. + */ + + +#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 int source; +static struct timer_list ktimer; + +/* + * The kernel timer + */ + +static void pps_ktimer_event(unsigned long ptr) +{ + struct timespec __ts; + struct pps_ktime ts; + + /* First of all we get the time stamp... */ + getnstimeofday(&__ts); + + pr_info("PPS event at %lu\n", jiffies); + + /* ... and translate it to PPS time data struct */ + ts.sec = __ts.tv_sec; + ts.nsec = __ts.tv_nsec; + + pps_event(source, &ts, PPS_CAPTUREASSERT, NULL); + + mod_timer(&ktimer, jiffies + HZ); +} + +/* + * The echo function + */ + +static void pps_ktimer_echo(int source, int event, void *data) +{ + pr_info("echo %s %s for source %d\n", + event & PPS_CAPTUREASSERT ? "assert" : "", + event & PPS_CAPTURECLEAR ? "clear" : "", + source); +} + +/* + * 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, + .echo = pps_ktimer_echo, + .owner = THIS_MODULE, +}; + +/* + * Module staff + */ + +static void __exit pps_ktimer_exit(void) +{ + del_timer_sync(&ktimer); + pps_unregister_source(source); + + pr_info("ktimer PPS source unregistered\n"); +} + +static int __init pps_ktimer_init(void) +{ + int ret; + + ret = pps_register_source(&pps_ktimer_info, + PPS_CAPTUREASSERT | PPS_OFFSETASSERT); + if (ret < 0) { + printk(KERN_ERR "cannot register ktimer source\n"); + return ret; + } + source = ret; + + setup_timer(&ktimer, pps_ktimer_event, 0); + mod_timer(&ktimer, jiffies + HZ); + + pr_info("ktimer PPS source registered at %d\n", source); + + 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"); |