[deliverable/linux.git] / drivers / watchdog / w83877f_wdt.c

/*
 *	W83877F Computer Watchdog Timer driver
 *
 *      Based on acquirewdt.c by Alan Cox,
 *           and sbc60xxwdt.c by Jakob Oestergaard <jakob@unthought.net>
 *
 *	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.
 *
 *	The authors do NOT admit liability nor provide warranty for
 *	any of this software. This material is provided "AS-IS" in
 *      the hope that it may be useful for others.
 *
 *	(c) Copyright 2001    Scott Jennings <linuxdrivers@oro.net>
 *
 *           4/19 - 2001      [Initial revision]
 *           9/27 - 2001      Added spinlocking
 *           4/12 - 2002      [rob@osinvestor.com] Eliminate extra comments
 *                            Eliminate fop_read
 *                            Eliminate extra spin_unlock
 *                            Added KERN_* tags to printks
 *                            add CONFIG_WATCHDOG_NOWAYOUT support
 *                            fix possible wdt_is_open race
 *                            changed watchdog_info to correctly reflect what the driver offers
 *                            added WDIOC_GETSTATUS, WDIOC_GETBOOTSTATUS, WDIOC_SETTIMEOUT,
 *                            WDIOC_GETTIMEOUT, and WDIOC_SETOPTIONS ioctls
 *           09/8 - 2003      [wim@iguana.be] cleanup of trailing spaces
 *                            added extra printk's for startup problems
 *                            use module_param
 *                            made timeout (the emulated heartbeat) a module_param
 *                            made the keepalive ping an internal subroutine
 *
 *  This WDT driver is different from most other Linux WDT
 *  drivers in that the driver will ping the watchdog by itself,
 *  because this particular WDT has a very short timeout (1.6
 *  seconds) and it would be insane to count on any userspace
 *  daemon always getting scheduled within that time frame.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/jiffies.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/fs.h>
#include <linux/ioport.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/system.h>

#define OUR_NAME "w83877f_wdt"
#define PFX OUR_NAME ": "

#define ENABLE_W83877F_PORT 0x3F0
#define ENABLE_W83877F 0x87
#define DISABLE_W83877F 0xAA
#define WDT_PING 0x443
#define WDT_REGISTER 0x14
#define WDT_ENABLE 0x9C
#define WDT_DISABLE 0x8C

/*
 * The W83877F seems to be fixed at 1.6s timeout (at least on the
 * EMACS PC-104 board I'm using). If we reset the watchdog every
 * ~250ms we should be safe.  */

#define WDT_INTERVAL (HZ/4+1)

/*
 * We must not require too good response from the userspace daemon.
 * Here we require the userspace daemon to send us a heartbeat
 * char to /dev/watchdog every 30 seconds.
 */

#define WATCHDOG_TIMEOUT 30            /* 30 sec default timeout */
static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");


static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

static void wdt_timer_ping(unsigned long);
static DEFINE_TIMER(timer, wdt_timer_ping, 0, 0);
static unsigned long next_heartbeat;
static unsigned long wdt_is_open;
static char wdt_expect_close;
static DEFINE_SPINLOCK(wdt_spinlock);

/*
 *	Whack the dog
 */

static void wdt_timer_ping(unsigned long data)
{
	/* If we got a heartbeat pulse within the WDT_US_INTERVAL
	 * we agree to ping the WDT
	 */
	if(time_before(jiffies, next_heartbeat))
	{
		/* Ping the WDT */
		spin_lock(&wdt_spinlock);

		/* Ping the WDT by reading from WDT_PING */
		inb_p(WDT_PING);

		/* Re-set the timer interval */
		mod_timer(&timer, jiffies + WDT_INTERVAL);

		spin_unlock(&wdt_spinlock);

	} else {
		printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
	}
}

/*
 * Utility routines
 */

static void wdt_change(int writeval)
{
	unsigned long flags;
	spin_lock_irqsave(&wdt_spinlock, flags);

	/* buy some time */
	inb_p(WDT_PING);

	/* make W83877F available */
	outb_p(ENABLE_W83877F,  ENABLE_W83877F_PORT);
	outb_p(ENABLE_W83877F,  ENABLE_W83877F_PORT);

	/* enable watchdog */
	outb_p(WDT_REGISTER,    ENABLE_W83877F_PORT);
	outb_p(writeval,        ENABLE_W83877F_PORT+1);

	/* lock the W8387FF away */
	outb_p(DISABLE_W83877F, ENABLE_W83877F_PORT);

	spin_unlock_irqrestore(&wdt_spinlock, flags);
}

static void wdt_startup(void)
{
	next_heartbeat = jiffies + (timeout * HZ);

	/* Start the timer */
	mod_timer(&timer, jiffies + WDT_INTERVAL);

	wdt_change(WDT_ENABLE);

	printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
}

static void wdt_turnoff(void)
{
	/* Stop the timer */
	del_timer(&timer);

	wdt_change(WDT_DISABLE);

	printk(KERN_INFO PFX "Watchdog timer is now disabled...\n");
}

static void wdt_keepalive(void)
{
	/* user land ping */
	next_heartbeat = jiffies + (timeout * HZ);
}

/*
 * /dev/watchdog handling
 */

static ssize_t fop_write(struct file * file, const char __user * buf, size_t count, loff_t * ppos)
{
	/* See if we got the magic character 'V' and reload the timer */
	if(count)
	{
		if (!nowayout)
		{
			size_t ofs;

			/* note: just in case someone wrote the magic character
			 * five months ago... */
			wdt_expect_close = 0;

			/* scan to see whether or not we got the magic character */
			for(ofs = 0; ofs != count; ofs++)
			{
				char c;
				if (get_user(c, buf + ofs))
					return -EFAULT;
				if (c == 'V')
					wdt_expect_close = 42;
			}
		}

		/* someone wrote to us, we should restart timer */
		wdt_keepalive();
	}
	return count;
}

static int fop_open(struct inode * inode, struct file * file)
{
	/* Just in case we're already talking to someone... */
	if(test_and_set_bit(0, &wdt_is_open))
		return -EBUSY;

	/* Good, fire up the show */
	wdt_startup();
	return nonseekable_open(inode, file);
}

static int fop_close(struct inode * inode, struct file * file)
{
	if(wdt_expect_close == 42)
		wdt_turnoff();
	else {
		del_timer(&timer);
		printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n");
	}
	clear_bit(0, &wdt_is_open);
	wdt_expect_close = 0;
	return 0;
}

static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
	unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	static struct watchdog_info ident=
	{
		.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
		.firmware_version = 1,
		.identity = "W83877F",
	};

	switch(cmd)
	{
		default:
			return -ENOTTY;
		case WDIOC_GETSUPPORT:
			return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0;
		case WDIOC_GETSTATUS:
		case WDIOC_GETBOOTSTATUS:
			return put_user(0, p);
		case WDIOC_KEEPALIVE:
			wdt_keepalive();
			return 0;
		case WDIOC_SETOPTIONS:
		{
			int new_options, retval = -EINVAL;

			if(get_user(new_options, p))
				return -EFAULT;

			if(new_options & WDIOS_DISABLECARD) {
				wdt_turnoff();
				retval = 0;
			}

			if(new_options & WDIOS_ENABLECARD) {
				wdt_startup();
				retval = 0;
			}

			return retval;
		}
		case WDIOC_SETTIMEOUT:
		{
			int new_timeout;

			if(get_user(new_timeout, p))
				return -EFAULT;

			if(new_timeout < 1 || new_timeout > 3600) /* arbitrary upper limit */
				return -EINVAL;

			timeout = new_timeout;
			wdt_keepalive();
			/* Fall through */
		}
		case WDIOC_GETTIMEOUT:
			return put_user(timeout, p);
	}
}

static const struct file_operations wdt_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.write		= fop_write,
	.open		= fop_open,
	.release	= fop_close,
	.ioctl		= fop_ioctl,
};

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

/*
 *	Notifier for system down
 */

static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
	void *unused)
{
	if(code==SYS_DOWN || code==SYS_HALT)
		wdt_turnoff();
	return NOTIFY_DONE;
}

/*
 *	The WDT needs to learn about soft shutdowns in order to
 *	turn the timebomb registers off.
 */

static struct notifier_block wdt_notifier=
{
	.notifier_call = wdt_notify_sys,
};

static void __exit w83877f_wdt_unload(void)
{
	wdt_turnoff();

	/* Deregister */
	misc_deregister(&wdt_miscdev);

	unregister_reboot_notifier(&wdt_notifier);
	release_region(WDT_PING,1);
	release_region(ENABLE_W83877F_PORT,2);
}

static int __init w83877f_wdt_init(void)
{
	int rc = -EBUSY;

	if(timeout < 1 || timeout > 3600) /* arbitrary upper limit */
	{
		timeout = WATCHDOG_TIMEOUT;
		printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n",
			timeout);
	}

	if (!request_region(ENABLE_W83877F_PORT, 2, "W83877F WDT"))
	{
		printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
			ENABLE_W83877F_PORT);
		rc = -EIO;
		goto err_out;
	}

	if (!request_region(WDT_PING, 1, "W8387FF WDT"))
	{
		printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
			WDT_PING);
		rc = -EIO;
		goto err_out_region1;
	}

	rc = register_reboot_notifier(&wdt_notifier);
	if (rc)
	{
		printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
			rc);
		goto err_out_region2;
	}

	rc = misc_register(&wdt_miscdev);
	if (rc)
	{
		printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
			wdt_miscdev.minor, rc);
		goto err_out_reboot;
	}

	printk(KERN_INFO PFX "WDT driver for W83877F initialised. timeout=%d sec (nowayout=%d)\n",
		timeout, nowayout);

	return 0;

err_out_reboot:
	unregister_reboot_notifier(&wdt_notifier);
err_out_region2:
	release_region(WDT_PING,1);
err_out_region1:
	release_region(ENABLE_W83877F_PORT,2);
err_out:
	return rc;
}

module_init(w83877f_wdt_init);
module_exit(w83877f_wdt_unload);

MODULE_AUTHOR("Scott and Bill Jennings");
MODULE_DESCRIPTION("Driver for watchdog timer in w83877f chip");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* W83877F Computer Watchdog Timer driver
	3	*
	4	* Based on acquirewdt.c by Alan Cox,
	5	* and sbc60xxwdt.c by Jakob Oestergaard <jakob@unthought.net>
	6	*
	7	* This program is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License
	9	* as published by the Free Software Foundation; either version
	10	* 2 of the License, or (at your option) any later version.
	11	*
	12	* The authors do NOT admit liability nor provide warranty for
	13	* any of this software. This material is provided "AS-IS" in
	14	* the hope that it may be useful for others.
	15	*
	16	* (c) Copyright 2001 Scott Jennings <linuxdrivers@oro.net>
	17	*
	18	* 4/19 - 2001 [Initial revision]
	19	* 9/27 - 2001 Added spinlocking
	20	* 4/12 - 2002 [rob@osinvestor.com] Eliminate extra comments
	21	* Eliminate fop_read
	22	* Eliminate extra spin_unlock
	23	* Added KERN_* tags to printks
	24	* add CONFIG_WATCHDOG_NOWAYOUT support
	25	* fix possible wdt_is_open race
	26	* changed watchdog_info to correctly reflect what the driver offers
	27	* added WDIOC_GETSTATUS, WDIOC_GETBOOTSTATUS, WDIOC_SETTIMEOUT,
	28	* WDIOC_GETTIMEOUT, and WDIOC_SETOPTIONS ioctls
	29	* 09/8 - 2003 [wim@iguana.be] cleanup of trailing spaces
	30	* added extra printk's for startup problems
	31	* use module_param
	32	* made timeout (the emulated heartbeat) a module_param
	33	* made the keepalive ping an internal subroutine
	34	*
	35	* This WDT driver is different from most other Linux WDT
	36	* drivers in that the driver will ping the watchdog by itself,
	37	* because this particular WDT has a very short timeout (1.6
	38	* seconds) and it would be insane to count on any userspace
	39	* daemon always getting scheduled within that time frame.
	40	*/
	41
	42	#include <linux/module.h>
	43	#include <linux/moduleparam.h>
	44	#include <linux/types.h>
	45	#include <linux/timer.h>
	46	#include <linux/jiffies.h>
	47	#include <linux/miscdevice.h>
	48	#include <linux/watchdog.h>
	49	#include <linux/fs.h>
	50	#include <linux/ioport.h>
	51	#include <linux/notifier.h>
	52	#include <linux/reboot.h>
	53	#include <linux/init.h>
	54	#include <asm/io.h>
	55	#include <asm/uaccess.h>
	56	#include <asm/system.h>
	57
	58	#define OUR_NAME "w83877f_wdt"
	59	#define PFX OUR_NAME ": "
	60
	61	#define ENABLE_W83877F_PORT 0x3F0
	62	#define ENABLE_W83877F 0x87
	63	#define DISABLE_W83877F 0xAA
	64	#define WDT_PING 0x443
65	#define WDT_REGISTER 0x14
66	#define WDT_ENABLE 0x9C
67	#define WDT_DISABLE 0x8C
68
69	/*
70	* The W83877F seems to be fixed at 1.6s timeout (at least on the
71	* EMACS PC-104 board I'm using). If we reset the watchdog every
72	* ~250ms we should be safe. */
73
74	#define WDT_INTERVAL (HZ/4+1)
75
76	/*
77	* We must not require too good response from the userspace daemon.
78	* Here we require the userspace daemon to send us a heartbeat
79	* char to /dev/watchdog every 30 seconds.
80	*/
81
82	#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
83	static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
84	module_param(timeout, int, 0);
85	MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
86
87
4bfdf378	88	static int nowayout = WATCHDOG_NOWAYOUT;
1da177e4	89	module_param(nowayout, int, 0);
bffda5c8	90	MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
1da177e4 LT	91
1da177e4 LT	92	static void wdt_timer_ping(unsigned long);
82eb7c50	93	static DEFINE_TIMER(timer, wdt_timer_ping, 0, 0);
1da177e4 LT	94	static unsigned long next_heartbeat;
	95	static unsigned long wdt_is_open;
	96	static char wdt_expect_close;
c7dfd0cc	97	static DEFINE_SPINLOCK(wdt_spinlock);
1da177e4 LT	98
	99	/*
	100	* Whack the dog
	101	*/
	102
	103	static void wdt_timer_ping(unsigned long data)
	104	{
	105	/* If we got a heartbeat pulse within the WDT_US_INTERVAL
	106	* we agree to ping the WDT
	107	*/
	108	if(time_before(jiffies, next_heartbeat))
	109	{
	110	/* Ping the WDT */
	111	spin_lock(&wdt_spinlock);
	112
	113	/* Ping the WDT by reading from WDT_PING */
	114	inb_p(WDT_PING);
	115
	116	/* Re-set the timer interval */
82eb7c50	117	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4 LT	118
	119	spin_unlock(&wdt_spinlock);
	120
	121	} else {
	122	printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
	123	}
	124	}
	125
	126	/*
	127	* Utility routines
	128	*/
	129
	130	static void wdt_change(int writeval)
	131	{
	132	unsigned long flags;
	133	spin_lock_irqsave(&wdt_spinlock, flags);
	134
	135	/* buy some time */
	136	inb_p(WDT_PING);
	137
	138	/* make W83877F available */
	139	outb_p(ENABLE_W83877F, ENABLE_W83877F_PORT);
	140	outb_p(ENABLE_W83877F, ENABLE_W83877F_PORT);
	141
	142	/* enable watchdog */
	143	outb_p(WDT_REGISTER, ENABLE_W83877F_PORT);
	144	outb_p(writeval, ENABLE_W83877F_PORT+1);
	145
	146	/* lock the W8387FF away */
	147	outb_p(DISABLE_W83877F, ENABLE_W83877F_PORT);
	148
	149	spin_unlock_irqrestore(&wdt_spinlock, flags);
	150	}
	151
	152	static void wdt_startup(void)
	153	{
	154	next_heartbeat = jiffies + (timeout * HZ);
	155
	156	/* Start the timer */
82eb7c50	157	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4 LT	158
	159	wdt_change(WDT_ENABLE);
	160
	161	printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
	162	}
	163
	164	static void wdt_turnoff(void)
	165	{
	166	/* Stop the timer */
	167	del_timer(&timer);
	168
	169	wdt_change(WDT_DISABLE);
	170
	171	printk(KERN_INFO PFX "Watchdog timer is now disabled...\n");
	172	}
	173
	174	static void wdt_keepalive(void)
	175	{
	176	/* user land ping */
	177	next_heartbeat = jiffies + (timeout * HZ);
	178	}
	179
	180	/*
	181	* /dev/watchdog handling
	182	*/
	183
	184	static ssize_t fop_write(struct file * file, const char __user * buf, size_t count, loff_t * ppos)
	185	{
	186	/* See if we got the magic character 'V' and reload the timer */
	187	if(count)
	188	{
	189	if (!nowayout)
	190	{
	191	size_t ofs;
	192
	193	/* note: just in case someone wrote the magic character
	194	* five months ago... */
	195	wdt_expect_close = 0;
	196
	197	/* scan to see whether or not we got the magic character */
	198	for(ofs = 0; ofs != count; ofs++)
	199	{
	200	char c;
	201	if (get_user(c, buf + ofs))
	202	return -EFAULT;
	203	if (c == 'V')
	204	wdt_expect_close = 42;
	205	}
	206	}
	207
	208	/* someone wrote to us, we should restart timer */
	209	wdt_keepalive();
	210	}
	211	return count;
	212	}
	213
	214	static int fop_open(struct inode * inode, struct file * file)
	215	{
	216	/* Just in case we're already talking to someone... */
	217	if(test_and_set_bit(0, &wdt_is_open))
	218	return -EBUSY;
	219
	220	/* Good, fire up the show */
	221	wdt_startup();
222	return nonseekable_open(inode, file);
223	}
224
225	static int fop_close(struct inode * inode, struct file * file)
226	{
227	if(wdt_expect_close == 42)
228	wdt_turnoff();
229	else {
230	del_timer(&timer);
231	printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n");
232	}
233	clear_bit(0, &wdt_is_open);
234	wdt_expect_close = 0;
235	return 0;
236	}
237
238	static int fop_ioctl(struct inode inode, struct file file, unsigned int cmd,
239	unsigned long arg)
240	{
241	void __user argp = (void __user )arg;
242	int __user *p = argp;
243	static struct watchdog_info ident=
244	{
245	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE,
246	.firmware_version = 1,
247	.identity = "W83877F",
248	};
249
250	switch(cmd)
251	{
252	default:
795b89d2	253	return -ENOTTY;
1da177e4 LT	254	case WDIOC_GETSUPPORT:
	255	return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0;
	256	case WDIOC_GETSTATUS:
	257	case WDIOC_GETBOOTSTATUS:
	258	return put_user(0, p);
	259	case WDIOC_KEEPALIVE:
	260	wdt_keepalive();
	261	return 0;
	262	case WDIOC_SETOPTIONS:
	263	{
	264	int new_options, retval = -EINVAL;
	265
	266	if(get_user(new_options, p))
	267	return -EFAULT;
	268
	269	if(new_options & WDIOS_DISABLECARD) {
	270	wdt_turnoff();
	271	retval = 0;
	272	}
	273
	274	if(new_options & WDIOS_ENABLECARD) {
	275	wdt_startup();
	276	retval = 0;
	277	}
	278
	279	return retval;
	280	}
	281	case WDIOC_SETTIMEOUT:
	282	{
	283	int new_timeout;
	284
	285	if(get_user(new_timeout, p))
	286	return -EFAULT;
	287
	288	if(new_timeout < 1 \|\| new_timeout > 3600) /* arbitrary upper limit */
	289	return -EINVAL;
	290
	291	timeout = new_timeout;
	292	wdt_keepalive();
	293	/* Fall through */
	294	}
	295	case WDIOC_GETTIMEOUT:
	296	return put_user(timeout, p);
	297	}
	298	}
	299
62322d25	300	static const struct file_operations wdt_fops = {
1da177e4 LT	301	.owner = THIS_MODULE,
	302	.llseek = no_llseek,
	303	.write = fop_write,
	304	.open = fop_open,
	305	.release = fop_close,
	306	.ioctl = fop_ioctl,
	307	};
	308
	309	static struct miscdevice wdt_miscdev = {
	310	.minor = WATCHDOG_MINOR,
	311	.name = "watchdog",
	312	.fops = &wdt_fops,
	313	};
	314
	315	/*
	316	* Notifier for system down
	317	*/
	318
	319	static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
	320	void *unused)
	321	{
	322	if(code==SYS_DOWN \|\| code==SYS_HALT)
	323	wdt_turnoff();
	324	return NOTIFY_DONE;
	325	}
	326
	327	/*
	328	* The WDT needs to learn about soft shutdowns in order to
	329	* turn the timebomb registers off.
	330	*/
	331
	332	static struct notifier_block wdt_notifier=
	333	{
	334	.notifier_call = wdt_notify_sys,
	335	};
	336
	337	static void __exit w83877f_wdt_unload(void)
	338	{
	339	wdt_turnoff();
	340
	341	/* Deregister */
	342	misc_deregister(&wdt_miscdev);
	343
	344	unregister_reboot_notifier(&wdt_notifier);
	345	release_region(WDT_PING,1);
	346	release_region(ENABLE_W83877F_PORT,2);
	347	}
	348
	349	static int __init w83877f_wdt_init(void)
	350	{
	351	int rc = -EBUSY;
	352
1da177e4 LT	353	if(timeout < 1 \|\| timeout > 3600) /* arbitrary upper limit */
	354	{
	355	timeout = WATCHDOG_TIMEOUT;
	356	printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n",
	357	timeout);
	358	}
	359
	360	if (!request_region(ENABLE_W83877F_PORT, 2, "W83877F WDT"))
	361	{
	362	printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
	363	ENABLE_W83877F_PORT);
	364	rc = -EIO;
	365	goto err_out;
	366	}
	367
	368	if (!request_region(WDT_PING, 1, "W8387FF WDT"))
	369	{
	370	printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
	371	WDT_PING);
	372	rc = -EIO;
	373	goto err_out_region1;
	374	}
	375
c6cb13ae	376	rc = register_reboot_notifier(&wdt_notifier);
1da177e4 LT	377	if (rc)
1da177e4 LT	378	{
c6cb13ae WVS	379	printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
c6cb13ae WVS	380	rc);
1da177e4 LT	381	goto err_out_region2;
	382	}
	383
c6cb13ae	384	rc = misc_register(&wdt_miscdev);
1da177e4 LT	385	if (rc)
1da177e4 LT	386	{
c6cb13ae WVS	387	printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
	388	wdt_miscdev.minor, rc);
	389	goto err_out_reboot;
1da177e4 LT	390	}
	391
	392	printk(KERN_INFO PFX "WDT driver for W83877F initialised. timeout=%d sec (nowayout=%d)\n",
	393	timeout, nowayout);
	394
	395	return 0;
	396
c6cb13ae WVS	397	err_out_reboot:
c6cb13ae WVS	398	unregister_reboot_notifier(&wdt_notifier);
1da177e4 LT	399	err_out_region2:
	400	release_region(WDT_PING,1);
	401	err_out_region1:
	402	release_region(ENABLE_W83877F_PORT,2);
	403	err_out:
	404	return rc;
	405	}
	406
	407	module_init(w83877f_wdt_init);
	408	module_exit(w83877f_wdt_unload);
	409
	410	MODULE_AUTHOR("Scott and Bill Jennings");
	411	MODULE_DESCRIPTION("Driver for watchdog timer in w83877f chip");
	412	MODULE_LICENSE("GPL");
	413	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);