Release 4.14 drivers/watchdog/ixp4xx_wdt.c

/*
 * drivers/char/watchdog/ixp4xx_wdt.c
 *
 * Watchdog driver for Intel IXP4xx network processors
 *
 * Author: Deepak Saxena <dsaxena@plexity.net>
 *
 * Copyright 2004 (c) MontaVista, Software, Inc.
 * Based on sa1100 driver, Copyright (C) 2000 Oleg Drokin <green@crimea.edu>
 *
 * This file is licensed under  the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */


#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/uaccess.h>
#include <mach/hardware.h>


static bool nowayout = WATCHDOG_NOWAYOUT;

static int heartbeat = 60;	
/* (secs) Default is 1 minute */

static unsigned long wdt_status;

static unsigned long boot_status;
static DEFINE_SPINLOCK(wdt_lock);


#define WDT_TICK_RATE (IXP4XX_PERIPHERAL_BUS_CLOCK * 1000000UL)


#define	WDT_IN_USE		0

#define	WDT_OK_TO_CLOSE		1



static void wdt_enable(void)
{
	spin_lock(&wdt_lock);
	*IXP4XX_OSWK = IXP4XX_WDT_KEY;
	*IXP4XX_OSWE = 0;
	*IXP4XX_OSWT = WDT_TICK_RATE * heartbeat;
	*IXP4XX_OSWE = IXP4XX_WDT_COUNT_ENABLE | IXP4XX_WDT_RESET_ENABLE;
	*IXP4XX_OSWK = 0;
	spin_unlock(&wdt_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
37
75.51%
1
50.00%
Alan Cox
12
24.49%
1
50.00%
Total
49
100.00%
2
100.00%



static void wdt_disable(void)
{
	spin_lock(&wdt_lock);
	*IXP4XX_OSWK = IXP4XX_WDT_KEY;
	*IXP4XX_OSWE = 0;
	*IXP4XX_OSWK = 0;
	spin_unlock(&wdt_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
23
65.71%
1
50.00%
Alan Cox
12
34.29%
1
50.00%
Total
35
100.00%
2
100.00%



static int ixp4xx_wdt_open(struct inode *inode, struct file *file)
{
	if (test_and_set_bit(WDT_IN_USE, &wdt_status))
		return -EBUSY;

	clear_bit(WDT_OK_TO_CLOSE, &wdt_status);
	wdt_enable();
	return nonseekable_open(inode, file);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
43
87.76%
1
50.00%
Linus Torvalds
6
12.24%
1
50.00%
Total
49
100.00%
2
100.00%


static ssize_t

ixp4xx_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos)
{
	if (len) {
		if (!nowayout) {
			size_t i;

			clear_bit(WDT_OK_TO_CLOSE, &wdt_status);

			for (i = 0; i != len; i++) {
				char c;

				if (get_user(c, data + i))
					return -EFAULT;
				if (c == 'V')
					set_bit(WDT_OK_TO_CLOSE, &wdt_status);
			}
		}
		wdt_enable();
	}
	return len;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
100
100.00%
1
100.00%
Total
100
100.00%
1
100.00%


static const struct watchdog_info ident = {
	.options	= WDIOF_CARDRESET | WDIOF_MAGICCLOSE |
			  WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
	.identity	= "IXP4xx Watchdog",
};




static long ixp4xx_wdt_ioctl(struct file *file, unsigned int cmd,
							unsigned long arg)
{
	int ret = -ENOTTY;
	int time;

	switch (cmd) {
	case WDIOC_GETSUPPORT:
		ret = copy_to_user((struct watchdog_info *)arg, &ident,
				   sizeof(ident)) ? -EFAULT : 0;
		break;

	case WDIOC_GETSTATUS:
		ret = put_user(0, (int *)arg);
		break;

	case WDIOC_GETBOOTSTATUS:
		ret = put_user(boot_status, (int *)arg);
		break;

	case WDIOC_KEEPALIVE:
		wdt_enable();
		ret = 0;
		break;

	case WDIOC_SETTIMEOUT:
		ret = get_user(time, (int *)arg);
		if (ret)
			break;

		if (time <= 0 || time > 60) {
			ret = -EINVAL;
			break;
		}

		heartbeat = time;
		wdt_enable();
		/* Fall through */

	case WDIOC_GETTIMEOUT:
		ret = put_user(heartbeat, (int *)arg);
		break;
	}
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
161
92.00%
1
25.00%
Wim Van Sebroeck
11
6.29%
1
25.00%
Alan Cox
2
1.14%
1
25.00%
Samuel Tardieu
1
0.57%
1
25.00%
Total
175
100.00%
4
100.00%



static int ixp4xx_wdt_release(struct inode *inode, struct file *file)
{
	if (test_bit(WDT_OK_TO_CLOSE, &wdt_status))
		wdt_disable();
	else
		pr_crit("Device closed unexpectedly - timer will not stop\n");
	clear_bit(WDT_IN_USE, &wdt_status);
	clear_bit(WDT_OK_TO_CLOSE, &wdt_status);

	return 0;
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
52
96.30%
1
50.00%
Joe Perches
2
3.70%
1
50.00%
Total
54
100.00%
2
100.00%


static const struct file_operations ixp4xx_wdt_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.write		= ixp4xx_wdt_write,
	.unlocked_ioctl	= ixp4xx_wdt_ioctl,
	.open		= ixp4xx_wdt_open,
	.release	= ixp4xx_wdt_release,
};


static struct miscdevice ixp4xx_wdt_miscdev = {
	.minor		= WATCHDOG_MINOR,
	.name		= "watchdog",
	.fops		= &ixp4xx_wdt_fops,
};



static int __init ixp4xx_wdt_init(void)
{
	int ret;

	if (!(read_cpuid_id() & 0xf) && !cpu_is_ixp46x()) {
		pr_err("Rev. A0 IXP42x CPU detected - watchdog disabled\n");

		return -ENODEV;
	}
	boot_status = (*IXP4XX_OSST & IXP4XX_OSST_TIMER_WARM_RESET) ?
			WDIOF_CARDRESET : 0;
	ret = misc_register(&ixp4xx_wdt_miscdev);
	if (ret == 0)
		pr_info("timer heartbeat %d sec\n", heartbeat);
	return ret;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
51
68.92%
1
20.00%
Alan Cox
13
17.57%
1
20.00%
Joe Perches
4
5.41%
1
20.00%
Deepak Saxena
4
5.41%
1
20.00%
Russell King
2
2.70%
1
20.00%
Total
74
100.00%
5
100.00%



static void __exit ixp4xx_wdt_exit(void)
{
	misc_deregister(&ixp4xx_wdt_miscdev);
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
15
100.00%
1
100.00%
Total
15
100.00%
1
100.00%


module_init(ixp4xx_wdt_init);

module_exit(ixp4xx_wdt_exit);

MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
MODULE_DESCRIPTION("IXP4xx Network Processor Watchdog");

module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds (default 60s)");

module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");

MODULE_LICENSE("GPL");
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Andrew Morton
676
87.23%
1
5.00%
Alan Cox
42
5.42%
1
5.00%
Wim Van Sebroeck
20
2.58%
5
25.00%
Joe Perches
13
1.68%
1
5.00%
Linus Torvalds
6
0.77%
1
5.00%
Adrian Bunk
5
0.65%
2
10.00%
Deepak Saxena
4
0.52%
1
5.00%
Russell King
3
0.39%
2
10.00%
Andrey Panin
1
0.13%
1
5.00%
Samuel Tardieu
1
0.13%
1
5.00%
Uwe Zeisberger
1
0.13%
1
5.00%
Arjan van de Ven
1
0.13%
1
5.00%
David Vrabel
1
0.13%
1
5.00%
Olaf Hering
1
0.13%
1
5.00%
Total
775
100.00%
20
100.00%
Directory: drivers/watchdog

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.