[mirror_ubuntu-artful-kernel.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 void
wdt_ping(void)
{
	spin_lock(&io_lock);
	w83697hf_select_wdt();

	w83697hf_write_timeout(timeout);

	w83697hf_deselect_wdt();
	spin_unlock(&io_lock);
}

static void
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);
}

static void
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);
}

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);
5794a9f4	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
03315adc	143	static void
089d8139	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);
f9a8c891 MJ	153	}
f9a8c891 MJ	154
03315adc	155	static void
089d8139	156	wdt_enable(void)
f9a8c891	157	{
089d8139 ST	158	spin_lock(&io_lock);
	159	w83697hf_select_wdt();
	160
	161	w83697hf_write_timeout(timeout);
	162	w83697hf_set_reg(0x30, 1); /* Enable timer */
	163
	164	w83697hf_deselect_wdt();
	165	spin_unlock(&io_lock);
f9a8c891 MJ	166	}
f9a8c891 MJ	167
03315adc	168	static void
f9a8c891 MJ	169	wdt_disable(void)
f9a8c891 MJ	170	{
089d8139 ST	171	spin_lock(&io_lock);
	172	w83697hf_select_wdt();
	173
	174	w83697hf_set_reg(0x30, 0); /* Disable timer */
	175	w83697hf_write_timeout(0);
	176
	177	w83697hf_deselect_wdt();
	178	spin_unlock(&io_lock);
f9a8c891 MJ	179	}
	180
	181	static int
	182	wdt_set_heartbeat(int t)
	183	{
eb64419e	184	if ((t < 1) \|\| (t > 255))
f9a8c891 MJ	185	return -EINVAL;
	186
	187	timeout = t;
	188	return 0;
	189	}
	190
	191	static ssize_t
	192	wdt_write(struct file file, const char __user buf, size_t count, loff_t *ppos)
	193	{
	194	if (count) {
	195	if (!nowayout) {
	196	size_t i;
	197
	198	expect_close = 0;
	199
	200	for (i = 0; i != count; i++) {
	201	char c;
	202	if (get_user(c, buf+i))
	203	return -EFAULT;
	204	if (c == 'V')
	205	expect_close = 42;
	206	}
	207	}
	208	wdt_ping();
	209	}
	210	return count;
	211	}
	212
	213	static int
	214	wdt_ioctl(struct inode inode, struct file file, unsigned int cmd,
	215	unsigned long arg)
	216	{
	217	void __user argp = (void __user )arg;
	218	int __user *p = argp;
	219	int new_timeout;
	220	static struct watchdog_info ident = {
	221	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE,
	222	.firmware_version = 1,
	223	.identity = "W83697HF WDT",
	224	};
	225
	226	switch (cmd) {
	227	case WDIOC_GETSUPPORT:
db16525e ST	228	if (copy_to_user(argp, &ident, sizeof(ident)))
	229	return -EFAULT;
	230	break;
f9a8c891 MJ	231
	232	case WDIOC_GETSTATUS:
	233	case WDIOC_GETBOOTSTATUS:
db16525e	234	return put_user(0, p);
f9a8c891 MJ	235
f9a8c891 MJ	236	case WDIOC_KEEPALIVE:
db16525e ST	237	wdt_ping();
db16525e ST	238	break;
f9a8c891 MJ	239
f9a8c891 MJ	240	case WDIOC_SETTIMEOUT:
db16525e ST	241	if (get_user(new_timeout, p))
	242	return -EFAULT;
	243	if (wdt_set_heartbeat(new_timeout))
	244	return -EINVAL;
	245	wdt_ping();
	246	/* Fall */
f9a8c891 MJ	247
f9a8c891 MJ	248	case WDIOC_GETTIMEOUT:
db16525e	249	return put_user(timeout, p);
f9a8c891 MJ	250
	251	case WDIOC_SETOPTIONS:
	252	{
db16525e	253	int options, retval = -EINVAL;
f9a8c891	254
db16525e ST	255	if (get_user(options, p))
db16525e ST	256	return -EFAULT;
f9a8c891	257
db16525e ST	258	if (options & WDIOS_DISABLECARD) {
	259	wdt_disable();
	260	retval = 0;
	261	}
f9a8c891	262
db16525e	263	if (options & WDIOS_ENABLECARD) {
089d8139	264	wdt_enable();
db16525e ST	265	retval = 0;
db16525e ST	266	}
f9a8c891	267
db16525e	268	return retval;
f9a8c891 MJ	269	}
	270
	271	default:
db16525e	272	return -ENOTTY;
f9a8c891 MJ	273	}
	274	return 0;
	275	}
	276
	277	static int
	278	wdt_open(struct inode inode, struct file file)
	279	{
	280	if (test_and_set_bit(0, &wdt_is_open))
	281	return -EBUSY;
	282	/*
	283	* Activate
	284	*/
	285
089d8139	286	wdt_enable();
f9a8c891 MJ	287	return nonseekable_open(inode, file);
	288	}
	289
	290	static int
	291	wdt_close(struct inode inode, struct file file)
	292	{
	293	if (expect_close == 42) {
	294	wdt_disable();
	295	} else {
db16525e	296	printk (KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
f9a8c891 MJ	297	wdt_ping();
	298	}
	299	expect_close = 0;
	300	clear_bit(0, &wdt_is_open);
	301	return 0;
	302	}
	303
	304	/*
	305	* Notifier for system down
	306	*/
	307
	308	static int
	309	wdt_notify_sys(struct notifier_block *this, unsigned long code,
	310	void *unused)
	311	{
	312	if (code == SYS_DOWN \|\| code == SYS_HALT) {
	313	/* Turn the WDT off */
	314	wdt_disable();
	315	}
	316	return NOTIFY_DONE;
	317	}
	318
	319	/*
	320	* Kernel Interfaces
	321	*/
	322
2b8693c0	323	static const struct file_operations wdt_fops = {
f9a8c891 MJ	324	.owner = THIS_MODULE,
	325	.llseek = no_llseek,
	326	.write = wdt_write,
	327	.ioctl = wdt_ioctl,
	328	.open = wdt_open,
	329	.release = wdt_close,
	330	};
	331
	332	static struct miscdevice wdt_miscdev = {
	333	.minor = WATCHDOG_MINOR,
	334	.name = "watchdog",
	335	.fops = &wdt_fops,
	336	};
	337
	338	/*
	339	* The WDT needs to learn about soft shutdowns in order to
	340	* turn the timebomb registers off.
	341	*/
	342
	343	static struct notifier_block wdt_notifier = {
	344	.notifier_call = wdt_notify_sys,
	345	};
	346
c81b2996 ST	347	static int
	348	w83697hf_check_wdt(void)
	349	{
	350	if (!request_region(wdt_io, 2, WATCHDOG_NAME)) {
	351	printk (KERN_ERR PFX "I/O address 0x%x already in use\n", wdt_io);
	352	return -EIO;
	353	}
	354
	355	printk (KERN_DEBUG PFX "Looking for watchdog at address 0x%x\n", wdt_io);
	356	w83697hf_unlock();
	357	if (w83697hf_get_reg(0x20) == 0x60) {
	358	printk (KERN_INFO PFX "watchdog found at address 0x%x\n", wdt_io);
	359	w83697hf_lock();
	360	return 0;
	361	}
	362	w83697hf_lock(); /* Reprotect in case it was a compatible device */
	363
	364	printk (KERN_INFO PFX "watchdog not found at address 0x%x\n", wdt_io);
	365	release_region(wdt_io, 2);
	366	return -EIO;
	367	}
	368
e223f01a WVS	369	static int w83697hf_ioports[] = { 0x2e, 0x4e, 0x00 };
e223f01a WVS	370
f9a8c891 MJ	371	static int __init
	372	wdt_init(void)
	373	{
e223f01a	374	int ret, i, found = 0;
f9a8c891	375
de710d68	376	printk (KERN_INFO PFX "WDT driver for W83697HF/HG initializing\n");
f9a8c891	377
e223f01a WVS	378	if (wdt_io == 0) {
	379	/* we will autodetect the W83697HF/HG watchdog */
	380	for (i = 0; ((!found) && (w83697hf_ioports[i] != 0)); i++) {
	381	wdt_io = w83697hf_ioports[i];
cde10ba3	382	if (!w83697hf_check_wdt())
e223f01a WVS	383	found++;
	384	}
	385	} else {
c81b2996	386	if (!w83697hf_check_wdt())
e223f01a	387	found++;
c81b2996 ST	388	}
c81b2996 ST	389
e223f01a WVS	390	if (!found) {
	391	printk (KERN_ERR PFX "No W83697HF/HG could be found\n");
	392	ret = -EIO;
	393	goto out;
	394	}
c81b2996	395
fa69afd3 ST	396	w83697hf_init();
fa69afd3 ST	397	wdt_disable(); /* Disable watchdog until first use */
c81b2996	398
f9a8c891 MJ	399	if (wdt_set_heartbeat(timeout)) {
f9a8c891 MJ	400	wdt_set_heartbeat(WATCHDOG_TIMEOUT);
eb64419e	401	printk (KERN_INFO PFX "timeout value must be 1<=timeout<=255, using %d\n",
f9a8c891 MJ	402	WATCHDOG_TIMEOUT);
	403	}
	404
f9a8c891 MJ	405	ret = register_reboot_notifier(&wdt_notifier);
	406	if (ret != 0) {
	407	printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
	408	ret);
	409	goto unreg_regions;
	410	}
	411
	412	ret = misc_register(&wdt_miscdev);
	413	if (ret != 0) {
	414	printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
	415	WATCHDOG_MINOR, ret);
	416	goto unreg_reboot;
	417	}
	418
	419	printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
	420	timeout, nowayout);
	421
	422	out:
	423	return ret;
	424	unreg_reboot:
	425	unregister_reboot_notifier(&wdt_notifier);
	426	unreg_regions:
b41a9f59	427	release_region(wdt_io, 2);
f9a8c891 MJ	428	goto out;
	429	}
	430
	431	static void __exit
	432	wdt_exit(void)
	433	{
	434	misc_deregister(&wdt_miscdev);
	435	unregister_reboot_notifier(&wdt_notifier);
b41a9f59	436	release_region(wdt_io, 2);
f9a8c891 MJ	437	}
	438
	439	module_init(wdt_init);
	440	module_exit(wdt_exit);
	441
	442	MODULE_LICENSE("GPL");
3fdee8db	443	MODULE_AUTHOR("Marcus Junker <junker@anduras.de>, Samuel Tardieu <sam@rfc1149.net>");
de710d68	444	MODULE_DESCRIPTION("w83697hf/hg WDT driver");
f9a8c891	445	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);