[linux-2.6-block.git] / drivers / watchdog / w83697hf_wdt.c

/*
 *	w83697hf/hg WDT driver
 *
 *	(c) Copyright 2006 Samuel Tardieu <sam@rfc1149.net>
 *	(c) Copyright 2006 Marcus Junker <junker@anduras.de>
 *
 *	Based on w83627hf_wdt.c which is based on advantechwdt.c
 *	which is based on wdt.c.
 *	Original copyright messages:
 *
 *	(c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
 *
 *	(c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
 *
 *	(c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
 *				http://www.redhat.com
 *
 *	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.
 *
 *	Neither Marcus Junker nor ANDURAS AG admit liability nor provide
 *	warranty for any of this software. This material is provided
 *	"AS-IS" and at no charge.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.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 <linux/spinlock.h>

#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/system.h>

#define WATCHDOG_NAME "w83697hf/hg WDT"
#define PFX WATCHDOG_NAME ": "
#define WATCHDOG_TIMEOUT 60		/* 60 sec default timeout */

static unsigned long wdt_is_open;
static char expect_close;
static DEFINE_SPINLOCK(io_lock);

/* You must set this - there is no sane way to probe for this board. */
static int wdt_io = 0x2e;
module_param(wdt_io, int, 0);
MODULE_PARM_DESC(wdt_io, "w83697hf/hg WDT io port (default 0x2e, 0 = autodetect)");

static int timeout = WATCHDOG_TIMEOUT;	/* in seconds */
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, 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) ")");

/*
 *	Kernel methods.
 */

#define W83697HF_EFER (wdt_io+0)	/* Extended Function Enable Register */
#define W83697HF_EFIR (wdt_io+0)	/* Extended Function Index Register (same as EFER) */
#define W83697HF_EFDR (wdt_io+1)	/* Extended Function Data Register */

static inline void
w83697hf_unlock(void)
{
	outb_p(0x87, W83697HF_EFER);	/* Enter extended function mode */
	outb_p(0x87, W83697HF_EFER);	/* Again according to manual */
}

static inline void
w83697hf_lock(void)
{
	outb_p(0xAA, W83697HF_EFER);	/* Leave extended function mode */
}

/*
 *	The three functions w83697hf_get_reg(), w83697hf_set_reg() and
 *	w83697hf_write_timeout() must be called with the device unlocked.
 */

static unsigned char
w83697hf_get_reg(unsigned char reg)
{
	outb_p(reg, W83697HF_EFIR);
	return inb_p(W83697HF_EFDR);
}

static void
w83697hf_set_reg(unsigned char reg, unsigned char data)
{
	outb_p(reg, W83697HF_EFIR);
	outb_p(data, W83697HF_EFDR);
}

static void
w83697hf_write_timeout(int timeout)
{
	w83697hf_set_reg(0xF4, timeout);	/* Write Timeout counter to CRF4 */
}

static void
w83697hf_select_wdt(void)
{
	w83697hf_unlock();
	w83697hf_set_reg(0x07, 0x08);	/* Switch to logic device 8 (GPIO2) */
}

static inline void
w83697hf_deselect_wdt(void)
{
	w83697hf_lock();
}

static void
w83697hf_init(void)
{
	unsigned char bbuf;

	w83697hf_select_wdt();

	bbuf = w83697hf_get_reg(0x29);
	bbuf &= ~0x60;
	bbuf |= 0x20;
	w83697hf_set_reg(0x29, bbuf);	/* Set pin 119 to WDTO# mode (= CR29, WDT0) */

	bbuf = w83697hf_get_reg(0xF3);
	bbuf &= ~0x04;
	w83697hf_set_reg(0xF3, bbuf);	/* Count mode is seconds */

	w83697hf_deselect_wdt();
}

static int
wdt_ping(void)
{
	spin_lock(&io_lock);
	w83697hf_select_wdt();

	w83697hf_write_timeout(timeout);

	w83697hf_deselect_wdt();
	spin_unlock(&io_lock);
	return 0;
}

static int
wdt_enable(void)
{
	spin_lock(&io_lock);
	w83697hf_select_wdt();

	w83697hf_write_timeout(timeout);
	w83697hf_set_reg(0x30, 1);	/* Enable timer */

	w83697hf_deselect_wdt();
	spin_unlock(&io_lock);
	return 0;
}

static int
wdt_disable(void)
{
	spin_lock(&io_lock);
	w83697hf_select_wdt();

	w83697hf_set_reg(0x30, 0);	/* Disable timer */
	w83697hf_write_timeout(0);

	w83697hf_deselect_wdt();
	spin_unlock(&io_lock);
	return 0;
}

static int
wdt_set_heartbeat(int t)
{
	if ((t < 1) || (t > 255))
		return -EINVAL;

	timeout = t;
	return 0;
}

static ssize_t
wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
	if (count) {
		if (!nowayout) {
			size_t i;

			expect_close = 0;

			for (i = 0; i != count; i++) {
				char c;
				if (get_user(c, buf+i))
					return -EFAULT;
				if (c == 'V')
					expect_close = 42;
			}
		}
		wdt_ping();
	}
	return count;
}

static int
wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
	  unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	int new_timeout;
	static struct watchdog_info ident = {
		.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
		.firmware_version = 1,
		.identity = "W83697HF WDT",
	};

	switch (cmd) {
	case WDIOC_GETSUPPORT:
		if (copy_to_user(argp, &ident, sizeof(ident)))
			return -EFAULT;
		break;

	case WDIOC_GETSTATUS:
	case WDIOC_GETBOOTSTATUS:
		return put_user(0, p);

	case WDIOC_KEEPALIVE:
		wdt_ping();
		break;

	case WDIOC_SETTIMEOUT:
		if (get_user(new_timeout, p))
			return -EFAULT;
		if (wdt_set_heartbeat(new_timeout))
			return -EINVAL;
		wdt_ping();
		/* Fall */

	case WDIOC_GETTIMEOUT:
		return put_user(timeout, p);

	case WDIOC_SETOPTIONS:
	{
		int options, retval = -EINVAL;

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

		if (options & WDIOS_DISABLECARD) {
			wdt_disable();
			retval = 0;
		}

		if (options & WDIOS_ENABLECARD) {
			wdt_enable();
			retval = 0;
		}

		return retval;
	}

	default:
		return -ENOTTY;
	}
	return 0;
}

static int
wdt_open(struct inode *inode, struct file *file)
{
	if (test_and_set_bit(0, &wdt_is_open))
		return -EBUSY;
	/*
	 *	Activate
	 */

	wdt_enable();
	return nonseekable_open(inode, file);
}

static int
wdt_close(struct inode *inode, struct file *file)
{
	if (expect_close == 42) {
		wdt_disable();
	} else {
		printk (KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
		wdt_ping();
	}
	expect_close = 0;
	clear_bit(0, &wdt_is_open);
	return 0;
}

/*
 *	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) {
		/* Turn the WDT off */
		wdt_disable();
	}
	return NOTIFY_DONE;
}

/*
 *	Kernel Interfaces
 */

static const struct file_operations wdt_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.write		= wdt_write,
	.ioctl		= wdt_ioctl,
	.open		= wdt_open,
	.release	= wdt_close,
};

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

/*
 *	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 int
w83697hf_check_wdt(void)
{
	if (!request_region(wdt_io, 2, WATCHDOG_NAME)) {
		printk (KERN_ERR PFX "I/O address 0x%x already in use\n", wdt_io);
		return -EIO;
	}

	printk (KERN_DEBUG PFX "Looking for watchdog at address 0x%x\n", wdt_io);
	w83697hf_unlock();
	if (w83697hf_get_reg(0x20) == 0x60) {
		printk (KERN_INFO PFX "watchdog found at address 0x%x\n", wdt_io);
		w83697hf_lock();
		return 0;
	}
	w83697hf_lock();	/* Reprotect in case it was a compatible device */

	printk (KERN_INFO PFX "watchdog not found at address 0x%x\n", wdt_io);
	release_region(wdt_io, 2);
	return -EIO;
}

static int w83697hf_ioports[] = { 0x2e, 0x4e, 0x00 };

static int __init
wdt_init(void)
{
	int ret, i, found = 0;

	printk (KERN_INFO PFX "WDT driver for W83697HF/HG initializing\n");

	if (wdt_io == 0) {
		/* we will autodetect the W83697HF/HG watchdog */
		for (i = 0; ((!found) && (w83697hf_ioports[i] != 0)); i++) {
			wdt_io = w83697hf_ioports[i];
			if (!w83697hf_check_wdt())
				found++;
		}
	} else {
		if (!w83697hf_check_wdt())
			found++;
	}

	if (!found) {
		printk (KERN_ERR PFX "No W83697HF/HG could be found\n");
		ret = -EIO;
		goto out;
	}

	w83697hf_init();
	wdt_disable();	/* Disable watchdog until first use */

	if (wdt_set_heartbeat(timeout)) {
		wdt_set_heartbeat(WATCHDOG_TIMEOUT);
		printk (KERN_INFO PFX "timeout value must be 1<=timeout<=255, using %d\n",
			WATCHDOG_TIMEOUT);
	}

	ret = register_reboot_notifier(&wdt_notifier);
	if (ret != 0) {
		printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
			ret);
		goto unreg_regions;
	}

	ret = misc_register(&wdt_miscdev);
	if (ret != 0) {
		printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
			WATCHDOG_MINOR, ret);
		goto unreg_reboot;
	}

	printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
		timeout, nowayout);

out:
	return ret;
unreg_reboot:
	unregister_reboot_notifier(&wdt_notifier);
unreg_regions:
	release_region(wdt_io, 2);
	goto out;
}

static void __exit
wdt_exit(void)
{
	misc_deregister(&wdt_miscdev);
	unregister_reboot_notifier(&wdt_notifier);
	release_region(wdt_io, 2);
}

module_init(wdt_init);
module_exit(wdt_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marcus Junker <junker@anduras.de>, Samuel Tardieu <sam@rfc1149.net>");
MODULE_DESCRIPTION("w83697hf/hg WDT driver");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
f9a8c891	1	/*
de710d68	2	* w83697hf/hg WDT driver
f9a8c891	3	*
3fdee8db	4	* (c) Copyright 2006 Samuel Tardieu <sam@rfc1149.net>
f9a8c891 MJ	5	* (c) Copyright 2006 Marcus Junker <junker@anduras.de>
f9a8c891 MJ	6	*
de710d68 ST	7	* Based on w83627hf_wdt.c which is based on advantechwdt.c
de710d68 ST	8	* which is based on wdt.c.
f9a8c891 MJ	9	* Original copyright messages:
f9a8c891 MJ	10	*
96de0e25	11	* (c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
f9a8c891 MJ	12	*
	13	* (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
	14	*
	15	* (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
	16	* http://www.redhat.com
	17	*
	18	* This program is free software; you can redistribute it and/or
	19	* modify it under the terms of the GNU General Public License
	20	* as published by the Free Software Foundation; either version
	21	* 2 of the License, or (at your option) any later version.
	22	*
	23	* Neither Marcus Junker nor ANDURAS AG admit liability nor provide
	24	* warranty for any of this software. This material is provided
	25	* "AS-IS" and at no charge.
	26	*/
	27
	28	#include <linux/module.h>
	29	#include <linux/moduleparam.h>
	30	#include <linux/types.h>
	31	#include <linux/miscdevice.h>
	32	#include <linux/watchdog.h>
	33	#include <linux/fs.h>
	34	#include <linux/ioport.h>
	35	#include <linux/notifier.h>
	36	#include <linux/reboot.h>
	37	#include <linux/init.h>
ab9d4414	38	#include <linux/spinlock.h>
f9a8c891 MJ	39
	40	#include <asm/io.h>
	41	#include <asm/uaccess.h>
	42	#include <asm/system.h>
	43
de710d68	44	#define WATCHDOG_NAME "w83697hf/hg WDT"
f9a8c891 MJ	45	#define PFX WATCHDOG_NAME ": "
	46	#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
	47
	48	static unsigned long wdt_is_open;
	49	static char expect_close;
c7dfd0cc	50	static DEFINE_SPINLOCK(io_lock);
f9a8c891 MJ	51
f9a8c891 MJ	52	/* You must set this - there is no sane way to probe for this board. */
c81b2996	53	static int wdt_io = 0x2e;
f9a8c891	54	module_param(wdt_io, int, 0);
c81b2996	55	MODULE_PARM_DESC(wdt_io, "w83697hf/hg WDT io port (default 0x2e, 0 = autodetect)");
f9a8c891 MJ	56
	57	static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
	58	module_param(timeout, int, 0);
eb64419e	59	MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
f9a8c891 MJ	60
	61	static int nowayout = WATCHDOG_NOWAYOUT;
	62	module_param(nowayout, int, 0);
bffda5c8	63	MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
f9a8c891 MJ	64
	65	/*
	66	* Kernel methods.
	67	*/
	68
44d7d328 ST	69	#define W83697HF_EFER (wdt_io+0) /* Extended Function Enable Register */
	70	#define W83697HF_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */
	71	#define W83697HF_EFDR (wdt_io+1) /* Extended Function Data Register */
f9a8c891	72
f7be3328 ST	73	static inline void
f7be3328 ST	74	w83697hf_unlock(void)
f9a8c891	75	{
44d7d328 ST	76	outb_p(0x87, W83697HF_EFER); /* Enter extended function mode */
44d7d328 ST	77	outb_p(0x87, W83697HF_EFER); /* Again according to manual */
f7be3328 ST	78	}
f7be3328 ST	79
fe851eba ST	80	static inline void
	81	w83697hf_lock(void)
	82	{
	83	outb_p(0xAA, W83697HF_EFER); /* Leave extended function mode */
	84	}
	85
0cd54476	86	/*
d46ab596 ST	87	* The three functions w83697hf_get_reg(), w83697hf_set_reg() and
d46ab596 ST	88	* w83697hf_write_timeout() must be called with the device unlocked.
0cd54476 ST	89	*/
	90
	91	static unsigned char
	92	w83697hf_get_reg(unsigned char reg)
	93	{
	94	outb_p(reg, W83697HF_EFIR);
	95	return inb_p(W83697HF_EFDR);
	96	}
	97
	98	static void
	99	w83697hf_set_reg(unsigned char reg, unsigned char data)
	100	{
	101	outb_p(reg, W83697HF_EFIR);
	102	outb_p(data, W83697HF_EFDR);
	103	}
	104
d46ab596 ST	105	static void
	106	w83697hf_write_timeout(int timeout)
	107	{
	108	w83697hf_set_reg(0xF4, timeout); /* Write Timeout counter to CRF4 */
	109	}
	110
a7933e05 ST	111	static void
	112	w83697hf_select_wdt(void)
	113	{
	114	w83697hf_unlock();
	115	w83697hf_set_reg(0x07, 0x08); /* Switch to logic device 8 (GPIO2) */
	116	}
	117
	118	static inline void
	119	w83697hf_deselect_wdt(void)
	120	{
	121	w83697hf_lock();
	122	}
	123
f9a8c891 MJ	124	static void
	125	w83697hf_init(void)
	126	{
b7b9868b	127	unsigned char bbuf;
f9a8c891	128
fa69afd3 ST	129	w83697hf_select_wdt();
fa69afd3 ST	130
b7b9868b ST	131	bbuf = w83697hf_get_reg(0x29);
	132	bbuf &= ~0x60;
	133	bbuf \|= 0x20;
	134	w83697hf_set_reg(0x29, bbuf); /* Set pin 119 to WDTO# mode (= CR29, WDT0) */
f9a8c891	135
b7b9868b ST	136	bbuf = w83697hf_get_reg(0xF3);
	137	bbuf &= ~0x04;
	138	w83697hf_set_reg(0xF3, bbuf); /* Count mode is seconds */
f9a8c891	139
fa69afd3	140	w83697hf_deselect_wdt();
f9a8c891 MJ	141	}
f9a8c891 MJ	142
089d8139 ST	143	static int
089d8139 ST	144	wdt_ping(void)
f9a8c891	145	{
ab9d4414	146	spin_lock(&io_lock);
a7933e05	147	w83697hf_select_wdt();
f9a8c891	148
d46ab596	149	w83697hf_write_timeout(timeout);
f9a8c891	150
a7933e05	151	w83697hf_deselect_wdt();
ab9d4414	152	spin_unlock(&io_lock);
089d8139	153	return 0;
f9a8c891 MJ	154	}
	155
	156	static int
089d8139	157	wdt_enable(void)
f9a8c891	158	{
089d8139 ST	159	spin_lock(&io_lock);
	160	w83697hf_select_wdt();
	161
	162	w83697hf_write_timeout(timeout);
	163	w83697hf_set_reg(0x30, 1); /* Enable timer */
	164
	165	w83697hf_deselect_wdt();
	166	spin_unlock(&io_lock);
f9a8c891 MJ	167	return 0;
	168	}
	169
	170	static int
	171	wdt_disable(void)
	172	{
089d8139 ST	173	spin_lock(&io_lock);
	174	w83697hf_select_wdt();
	175
	176	w83697hf_set_reg(0x30, 0); /* Disable timer */
	177	w83697hf_write_timeout(0);
	178
	179	w83697hf_deselect_wdt();
	180	spin_unlock(&io_lock);
f9a8c891 MJ	181	return 0;
	182	}
	183
	184	static int
	185	wdt_set_heartbeat(int t)
	186	{
eb64419e	187	if ((t < 1) \|\| (t > 255))
f9a8c891 MJ	188	return -EINVAL;
	189
	190	timeout = t;
	191	return 0;
	192	}
	193
	194	static ssize_t
	195	wdt_write(struct file file, const char __user buf, size_t count, loff_t *ppos)
	196	{
	197	if (count) {
	198	if (!nowayout) {
	199	size_t i;
	200
	201	expect_close = 0;
	202
	203	for (i = 0; i != count; i++) {
	204	char c;
	205	if (get_user(c, buf+i))
	206	return -EFAULT;
	207	if (c == 'V')
	208	expect_close = 42;
	209	}
	210	}
	211	wdt_ping();
	212	}
	213	return count;
	214	}
	215
	216	static int
	217	wdt_ioctl(struct inode inode, struct file file, unsigned int cmd,
	218	unsigned long arg)
	219	{
	220	void __user argp = (void __user )arg;
	221	int __user *p = argp;
	222	int new_timeout;
	223	static struct watchdog_info ident = {
	224	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE,
	225	.firmware_version = 1,
	226	.identity = "W83697HF WDT",
	227	};
	228
	229	switch (cmd) {
	230	case WDIOC_GETSUPPORT:
db16525e ST	231	if (copy_to_user(argp, &ident, sizeof(ident)))
	232	return -EFAULT;
	233	break;
f9a8c891 MJ	234
	235	case WDIOC_GETSTATUS:
	236	case WDIOC_GETBOOTSTATUS:
db16525e	237	return put_user(0, p);
f9a8c891 MJ	238
f9a8c891 MJ	239	case WDIOC_KEEPALIVE:
db16525e ST	240	wdt_ping();
db16525e ST	241	break;
f9a8c891 MJ	242
f9a8c891 MJ	243	case WDIOC_SETTIMEOUT:
db16525e ST	244	if (get_user(new_timeout, p))
	245	return -EFAULT;
	246	if (wdt_set_heartbeat(new_timeout))
	247	return -EINVAL;
	248	wdt_ping();
	249	/* Fall */
f9a8c891 MJ	250
f9a8c891 MJ	251	case WDIOC_GETTIMEOUT:
db16525e	252	return put_user(timeout, p);
f9a8c891 MJ	253
	254	case WDIOC_SETOPTIONS:
	255	{
db16525e	256	int options, retval = -EINVAL;
f9a8c891	257
db16525e ST	258	if (get_user(options, p))
db16525e ST	259	return -EFAULT;
f9a8c891	260
db16525e ST	261	if (options & WDIOS_DISABLECARD) {
	262	wdt_disable();
	263	retval = 0;
	264	}
f9a8c891	265
db16525e	266	if (options & WDIOS_ENABLECARD) {
089d8139	267	wdt_enable();
db16525e ST	268	retval = 0;
db16525e ST	269	}
f9a8c891	270
db16525e	271	return retval;
f9a8c891 MJ	272	}
	273
	274	default:
db16525e	275	return -ENOTTY;
f9a8c891 MJ	276	}
	277	return 0;
	278	}
	279
	280	static int
	281	wdt_open(struct inode inode, struct file file)
	282	{
	283	if (test_and_set_bit(0, &wdt_is_open))
	284	return -EBUSY;
	285	/*
	286	* Activate
	287	*/
	288
089d8139	289	wdt_enable();
f9a8c891 MJ	290	return nonseekable_open(inode, file);
	291	}
	292
	293	static int
	294	wdt_close(struct inode inode, struct file file)
	295	{
	296	if (expect_close == 42) {
	297	wdt_disable();
	298	} else {
db16525e	299	printk (KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
f9a8c891 MJ	300	wdt_ping();
	301	}
	302	expect_close = 0;
	303	clear_bit(0, &wdt_is_open);
	304	return 0;
	305	}
	306
	307	/*
	308	* Notifier for system down
	309	*/
	310
	311	static int
	312	wdt_notify_sys(struct notifier_block *this, unsigned long code,
	313	void *unused)
	314	{
	315	if (code == SYS_DOWN \|\| code == SYS_HALT) {
	316	/* Turn the WDT off */
	317	wdt_disable();
	318	}
	319	return NOTIFY_DONE;
	320	}
	321
	322	/*
	323	* Kernel Interfaces
	324	*/
	325
2b8693c0	326	static const struct file_operations wdt_fops = {
f9a8c891 MJ	327	.owner = THIS_MODULE,
	328	.llseek = no_llseek,
	329	.write = wdt_write,
	330	.ioctl = wdt_ioctl,
	331	.open = wdt_open,
	332	.release = wdt_close,
	333	};
	334
	335	static struct miscdevice wdt_miscdev = {
	336	.minor = WATCHDOG_MINOR,
	337	.name = "watchdog",
	338	.fops = &wdt_fops,
	339	};
	340
	341	/*
	342	* The WDT needs to learn about soft shutdowns in order to
	343	* turn the timebomb registers off.
	344	*/
	345
	346	static struct notifier_block wdt_notifier = {
	347	.notifier_call = wdt_notify_sys,
	348	};
	349
c81b2996 ST	350	static int
	351	w83697hf_check_wdt(void)
	352	{
	353	if (!request_region(wdt_io, 2, WATCHDOG_NAME)) {
	354	printk (KERN_ERR PFX "I/O address 0x%x already in use\n", wdt_io);
	355	return -EIO;
	356	}
	357
	358	printk (KERN_DEBUG PFX "Looking for watchdog at address 0x%x\n", wdt_io);
	359	w83697hf_unlock();
	360	if (w83697hf_get_reg(0x20) == 0x60) {
	361	printk (KERN_INFO PFX "watchdog found at address 0x%x\n", wdt_io);
	362	w83697hf_lock();
	363	return 0;
	364	}
	365	w83697hf_lock(); /* Reprotect in case it was a compatible device */
	366
	367	printk (KERN_INFO PFX "watchdog not found at address 0x%x\n", wdt_io);
	368	release_region(wdt_io, 2);
	369	return -EIO;
	370	}
	371
e223f01a WVS	372	static int w83697hf_ioports[] = { 0x2e, 0x4e, 0x00 };
e223f01a WVS	373
f9a8c891 MJ	374	static int __init
	375	wdt_init(void)
	376	{
e223f01a	377	int ret, i, found = 0;
f9a8c891	378
de710d68	379	printk (KERN_INFO PFX "WDT driver for W83697HF/HG initializing\n");
f9a8c891	380
e223f01a WVS	381	if (wdt_io == 0) {
	382	/* we will autodetect the W83697HF/HG watchdog */
	383	for (i = 0; ((!found) && (w83697hf_ioports[i] != 0)); i++) {
	384	wdt_io = w83697hf_ioports[i];
cde10ba3	385	if (!w83697hf_check_wdt())
e223f01a WVS	386	found++;
	387	}
	388	} else {
c81b2996	389	if (!w83697hf_check_wdt())
e223f01a	390	found++;
c81b2996 ST	391	}
c81b2996 ST	392
e223f01a WVS	393	if (!found) {
	394	printk (KERN_ERR PFX "No W83697HF/HG could be found\n");
	395	ret = -EIO;
	396	goto out;
	397	}
c81b2996	398
fa69afd3 ST	399	w83697hf_init();
fa69afd3 ST	400	wdt_disable(); /* Disable watchdog until first use */
c81b2996	401
f9a8c891 MJ	402	if (wdt_set_heartbeat(timeout)) {
f9a8c891 MJ	403	wdt_set_heartbeat(WATCHDOG_TIMEOUT);
eb64419e	404	printk (KERN_INFO PFX "timeout value must be 1<=timeout<=255, using %d\n",
f9a8c891 MJ	405	WATCHDOG_TIMEOUT);
	406	}
	407
f9a8c891 MJ	408	ret = register_reboot_notifier(&wdt_notifier);
	409	if (ret != 0) {
	410	printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
	411	ret);
	412	goto unreg_regions;
	413	}
	414
	415	ret = misc_register(&wdt_miscdev);
	416	if (ret != 0) {
	417	printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
	418	WATCHDOG_MINOR, ret);
	419	goto unreg_reboot;
	420	}
	421
	422	printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
	423	timeout, nowayout);
	424
	425	out:
	426	return ret;
	427	unreg_reboot:
	428	unregister_reboot_notifier(&wdt_notifier);
	429	unreg_regions:
b41a9f59	430	release_region(wdt_io, 2);
f9a8c891 MJ	431	goto out;
	432	}
	433
	434	static void __exit
	435	wdt_exit(void)
	436	{
	437	misc_deregister(&wdt_miscdev);
	438	unregister_reboot_notifier(&wdt_notifier);
b41a9f59	439	release_region(wdt_io, 2);
f9a8c891 MJ	440	}
	441
	442	module_init(wdt_init);
	443	module_exit(wdt_exit);
	444
	445	MODULE_LICENSE("GPL");
3fdee8db	446	MODULE_AUTHOR("Marcus Junker <junker@anduras.de>, Samuel Tardieu <sam@rfc1149.net>");
de710d68	447	MODULE_DESCRIPTION("w83697hf/hg WDT driver");
f9a8c891	448	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);