[deliverable/linux.git] / drivers / watchdog / w83697ug_wdt.c

/*
 *	w83697ug/uf WDT driver
 *
 *	(c) Copyright 2008 Flemming Fransen <ff@nrvissing.net>
 *		reused original code to support w83697ug/uf.
 *
 *	Based on w83627hf_wdt.c which is based on advantechwdt.c
 *	which is based on wdt.c.
 *	Original copyright messages:
 *
 *	(c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
 *		added support for W83627THF.
 *
 *	(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 Alan Cox nor CymruNet Ltd. admit liability nor provide
 *	warranty for any of this software. This material is provided
 *	"AS-IS" and at no charge.
 *
 *	(c) Copyright 1995    Alan Cox <alan@redhat.com>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#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 <linux/io.h>
#include <linux/uaccess.h>

#include <asm/system.h>

#define WATCHDOG_NAME "w83697ug/uf WDT"
#define WATCHDOG_TIMEOUT 60		/* 60 sec default timeout */

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

static int wdt_io = 0x2e;
module_param(wdt_io, int, 0);
MODULE_PARM_DESC(wdt_io, "w83697ug/uf WDT io port (default 0x2e)");

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

/*
 *	Kernel methods.
 */

#define WDT_EFER (wdt_io+0)   /* Extended Function Enable Registers */
#define WDT_EFIR (wdt_io+0)   /* Extended Function Index Register
							(same as EFER) */
#define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */

static int w83697ug_select_wd_register(void)
{
	unsigned char c;
	unsigned char version;

	outb_p(0x87, WDT_EFER); /* Enter extended function mode */
	outb_p(0x87, WDT_EFER); /* Again according to manual */

	outb(0x20, WDT_EFER);	/* check chip version	*/
	version = inb(WDT_EFDR);

	if (version == 0x68) {	/* W83697UG		*/
		pr_info("Watchdog chip version 0x%02x = W83697UG/UF found at 0x%04x\n",
			version, wdt_io);

		outb_p(0x2b, WDT_EFER);
		c = inb_p(WDT_EFDR);    /* select WDT0 */
		c &= ~0x04;
		outb_p(0x2b, WDT_EFER);
		outb_p(c, WDT_EFDR);	/* set pin118 to WDT0 */

	} else {
		pr_err("No W83697UG/UF could be found\n");
		return -ENODEV;
	}

	outb_p(0x07, WDT_EFER); /* point to logical device number reg */
	outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */
	outb_p(0x30, WDT_EFER); /* select CR30 */
	c = inb_p(WDT_EFDR);
	outb_p(c | 0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */

	return 0;
}

static void w83697ug_unselect_wd_register(void)
{
	outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
}

static int w83697ug_init(void)
{
	int ret;
	unsigned char t;

	ret = w83697ug_select_wd_register();
	if (ret != 0)
		return ret;

	outb_p(0xF6, WDT_EFER); /* Select CRF6 */
	t = inb_p(WDT_EFDR);    /* read CRF6 */
	if (t != 0) {
		pr_info("Watchdog already running. Resetting timeout to %d sec\n",
			timeout);
		outb_p(timeout, WDT_EFDR);    /* Write back to CRF6 */
	}
	outb_p(0xF5, WDT_EFER); /* Select CRF5 */
	t = inb_p(WDT_EFDR);    /* read CRF5 */
	t &= ~0x0C;             /* set second mode &
					disable keyboard turning off watchdog */
	outb_p(t, WDT_EFDR);    /* Write back to CRF5 */

	w83697ug_unselect_wd_register();
	return 0;
}

static void wdt_ctrl(int timeout)
{
	spin_lock(&io_lock);

	if (w83697ug_select_wd_register() < 0) {
		spin_unlock(&io_lock);
		return;
	}

	outb_p(0xF4, WDT_EFER);    /* Select CRF4 */
	outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */

	w83697ug_unselect_wd_register();

	spin_unlock(&io_lock);
}

static int wdt_ping(void)
{
	wdt_ctrl(timeout);
	return 0;
}

static int wdt_disable(void)
{
	wdt_ctrl(0);
	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 long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	int new_timeout;
	static const struct watchdog_info ident = {
		.options =		WDIOF_KEEPALIVEPING |
					WDIOF_SETTIMEOUT |
					WDIOF_MAGICCLOSE,
		.firmware_version =	1,
		.identity =		"W83697UG 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_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_ping();
			retval = 0;
		}

		return retval;
	}

	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);

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

static int wdt_close(struct inode *inode, struct file *file)
{
	if (expect_close == 42)
		wdt_disable();
	else {
		pr_crit("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)
		wdt_disable();	/* Turn the WDT off */

	return NOTIFY_DONE;
}

/*
 *	Kernel Interfaces
 */

static const struct file_operations wdt_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.write		= wdt_write,
	.unlocked_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 __init wdt_init(void)
{
	int ret;

	pr_info("WDT driver for the Winbond(TM) W83697UG/UF Super I/O chip initialising\n");

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

	if (!request_region(wdt_io, 1, WATCHDOG_NAME)) {
		pr_err("I/O address 0x%04x already in use\n", wdt_io);
		ret = -EIO;
		goto out;
	}

	ret = w83697ug_init();
	if (ret != 0)
		goto unreg_regions;

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

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

	pr_info("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, 1);
	goto out;
}

static void __exit wdt_exit(void)
{
	misc_deregister(&wdt_miscdev);
	unregister_reboot_notifier(&wdt_notifier);
	release_region(wdt_io, 1);
}

module_init(wdt_init);
module_exit(wdt_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Flemming Frandsen <ff@nrvissing.net>");
MODULE_DESCRIPTION("w83697ug/uf WDT driver");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
7d8b0906 FF	1	/*
	2	* w83697ug/uf WDT driver
	3	*
	4	* (c) Copyright 2008 Flemming Fransen <ff@nrvissing.net>
143a2e54	5	* reused original code to support w83697ug/uf.
7d8b0906 FF	6	*
	7	* Based on w83627hf_wdt.c which is based on advantechwdt.c
	8	* which is based on wdt.c.
	9	* Original copyright messages:
	10	*
	11	* (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
	12	* added support for W83627THF.
	13	*
	14	* (c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
	15	*
	16	* (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
	17	*
	18	* (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
	19	* http://www.redhat.com
	20	*
	21	* This program is free software; you can redistribute it and/or
	22	* modify it under the terms of the GNU General Public License
	23	* as published by the Free Software Foundation; either version
	24	* 2 of the License, or (at your option) any later version.
	25	*
	26	* Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
	27	* warranty for any of this software. This material is provided
	28	* "AS-IS" and at no charge.
	29	*
	30	* (c) Copyright 1995 Alan Cox <alan@redhat.com>
	31	*/
	32
27c766aa JP	33	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27c766aa JP	34
7d8b0906 FF	35	#include <linux/module.h>
	36	#include <linux/moduleparam.h>
	37	#include <linux/types.h>
	38	#include <linux/miscdevice.h>
	39	#include <linux/watchdog.h>
	40	#include <linux/fs.h>
	41	#include <linux/ioport.h>
	42	#include <linux/notifier.h>
	43	#include <linux/reboot.h>
	44	#include <linux/init.h>
	45	#include <linux/spinlock.h>
	46	#include <linux/io.h>
	47	#include <linux/uaccess.h>
	48
	49	#include <asm/system.h>
	50
	51	#define WATCHDOG_NAME "w83697ug/uf WDT"
7d8b0906 FF	52	#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
	53
	54	static unsigned long wdt_is_open;
	55	static char expect_close;
	56	static DEFINE_SPINLOCK(io_lock);
	57
	58	static int wdt_io = 0x2e;
	59	module_param(wdt_io, int, 0);
	60	MODULE_PARM_DESC(wdt_io, "w83697ug/uf WDT io port (default 0x2e)");
	61
	62	static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
	63	module_param(timeout, int, 0);
	64	MODULE_PARM_DESC(timeout,
	65	"Watchdog timeout in seconds. 1<= timeout <=255 (default="
	66	__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
	67
86a1e189 WVS	68	static bool nowayout = WATCHDOG_NOWAYOUT;
86a1e189 WVS	69	module_param(nowayout, bool, 0);
7d8b0906 FF	70	MODULE_PARM_DESC(nowayout,
	71	"Watchdog cannot be stopped once started (default="
	72	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
	73
	74	/*
	75	* Kernel methods.
	76	*/
	77
	78	#define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */
	79	#define WDT_EFIR (wdt_io+0) /* Extended Function Index Register
	80	(same as EFER) */
	81	#define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
	82
63bad145	83	static int w83697ug_select_wd_register(void)
7d8b0906 FF	84	{
	85	unsigned char c;
	86	unsigned char version;
	87
	88	outb_p(0x87, WDT_EFER); /* Enter extended function mode */
	89	outb_p(0x87, WDT_EFER); /* Again according to manual */
	90
5f3b2756	91	outb(0x20, WDT_EFER); /* check chip version */
7d8b0906 FF	92	version = inb(WDT_EFDR);
7d8b0906 FF	93
5f3b2756	94	if (version == 0x68) { /* W83697UG */
27c766aa JP	95	pr_info("Watchdog chip version 0x%02x = W83697UG/UF found at 0x%04x\n",
27c766aa JP	96	version, wdt_io);
7d8b0906 FF	97
	98	outb_p(0x2b, WDT_EFER);
	99	c = inb_p(WDT_EFDR); /* select WDT0 */
	100	c &= ~0x04;
	101	outb_p(0x2b, WDT_EFER);
	102	outb_p(c, WDT_EFDR); /* set pin118 to WDT0 */
	103
	104	} else {
27c766aa	105	pr_err("No W83697UG/UF could be found\n");
63bad145	106	return -ENODEV;
7d8b0906 FF	107	}
	108
	109	outb_p(0x07, WDT_EFER); /* point to logical device number reg */
	110	outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */
	111	outb_p(0x30, WDT_EFER); /* select CR30 */
	112	c = inb_p(WDT_EFDR);
943413c5	113	outb_p(c \| 0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */
63bad145 EL	114
63bad145 EL	115	return 0;
7d8b0906 FF	116	}
	117
	118	static void w83697ug_unselect_wd_register(void)
	119	{
	120	outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
	121	}
	122
63bad145	123	static int w83697ug_init(void)
7d8b0906	124	{
63bad145	125	int ret;
7d8b0906 FF	126	unsigned char t;
7d8b0906 FF	127
63bad145 EL	128	ret = w83697ug_select_wd_register();
	129	if (ret != 0)
	130	return ret;
7d8b0906 FF	131
	132	outb_p(0xF6, WDT_EFER); /* Select CRF6 */
	133	t = inb_p(WDT_EFDR); /* read CRF6 */
	134	if (t != 0) {
27c766aa JP	135	pr_info("Watchdog already running. Resetting timeout to %d sec\n",
27c766aa JP	136	timeout);
7d8b0906 FF	137	outb_p(timeout, WDT_EFDR); /* Write back to CRF6 */
	138	}
	139	outb_p(0xF5, WDT_EFER); /* Select CRF5 */
	140	t = inb_p(WDT_EFDR); /* read CRF5 */
	141	t &= ~0x0C; /* set second mode &
	142	disable keyboard turning off watchdog */
	143	outb_p(t, WDT_EFDR); /* Write back to CRF5 */
	144
	145	w83697ug_unselect_wd_register();
63bad145	146	return 0;
7d8b0906 FF	147	}
	148
	149	static void wdt_ctrl(int timeout)
	150	{
	151	spin_lock(&io_lock);
	152
db5d2d8a JS	153	if (w83697ug_select_wd_register() < 0) {
db5d2d8a JS	154	spin_unlock(&io_lock);
63bad145	155	return;
db5d2d8a	156	}
7d8b0906 FF	157
	158	outb_p(0xF4, WDT_EFER); /* Select CRF4 */
	159	outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF4 */
	160
	161	w83697ug_unselect_wd_register();
	162
	163	spin_unlock(&io_lock);
	164	}
	165
	166	static int wdt_ping(void)
	167	{
	168	wdt_ctrl(timeout);
	169	return 0;
	170	}
	171
	172	static int wdt_disable(void)
	173	{
	174	wdt_ctrl(0);
	175	return 0;
	176	}
	177
	178	static int wdt_set_heartbeat(int t)
	179	{
	180	if (t < 1 \|\| t > 255)
	181	return -EINVAL;
	182
	183	timeout = t;
	184	return 0;
	185	}
	186
	187	static ssize_t wdt_write(struct file file, const char __user buf,
	188	size_t count, loff_t *ppos)
	189	{
	190	if (count) {
	191	if (!nowayout) {
	192	size_t i;
	193
	194	expect_close = 0;
	195
	196	for (i = 0; i != count; i++) {
	197	char c;
	198	if (get_user(c, buf + i))
	199	return -EFAULT;
	200	if (c == 'V')
	201	expect_close = 42;
	202	}
	203	}
	204	wdt_ping();
	205	}
	206	return count;
	207	}
	208
	209	static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	210	{
	211	void __user argp = (void __user )arg;
	212	int __user *p = argp;
	213	int new_timeout;
	214	static const struct watchdog_info ident = {
	215	.options = WDIOF_KEEPALIVEPING \|
	216	WDIOF_SETTIMEOUT \|
	217	WDIOF_MAGICCLOSE,
	218	.firmware_version = 1,
	219	.identity = "W83697UG WDT",
	220	};
221
222	switch (cmd) {
223	case WDIOC_GETSUPPORT:
224	if (copy_to_user(argp, &ident, sizeof(ident)))
225	return -EFAULT;
226	break;
227
228	case WDIOC_GETSTATUS:
229	case WDIOC_GETBOOTSTATUS:
230	return put_user(0, p);
231
232	case WDIOC_SETOPTIONS:
233	{
234	int options, retval = -EINVAL;
235
236	if (get_user(options, p))
237	return -EFAULT;
238
239	if (options & WDIOS_DISABLECARD) {
240	wdt_disable();
241	retval = 0;
242	}
243
244	if (options & WDIOS_ENABLECARD) {
245	wdt_ping();
246	retval = 0;
247	}
248
249	return retval;
250	}
251
252	case WDIOC_KEEPALIVE:
253	wdt_ping();
254	break;
255
256	case WDIOC_SETTIMEOUT:
257	if (get_user(new_timeout, p))
258	return -EFAULT;
259	if (wdt_set_heartbeat(new_timeout))
260	return -EINVAL;
261	wdt_ping();
262	/* Fall */
263
264	case WDIOC_GETTIMEOUT:
265	return put_user(timeout, p);
266
267	default:
268	return -ENOTTY;
269	}
270	return 0;
271	}
272
273	static int wdt_open(struct inode inode, struct file file)
274	{
275	if (test_and_set_bit(0, &wdt_is_open))
276	return -EBUSY;
277	/*
278	* Activate
279	*/
280
281	wdt_ping();
282	return nonseekable_open(inode, file);
283	}
284
285	static int wdt_close(struct inode inode, struct file file)
286	{
287	if (expect_close == 42)
288	wdt_disable();
289	else {
27c766aa	290	pr_crit("Unexpected close, not stopping watchdog!\n");
7d8b0906 FF	291	wdt_ping();
	292	}
	293	expect_close = 0;
	294	clear_bit(0, &wdt_is_open);
	295	return 0;
	296	}
	297
	298	/*
	299	* Notifier for system down
	300	*/
	301
	302	static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
	303	void *unused)
	304	{
	305	if (code == SYS_DOWN \|\| code == SYS_HALT)
	306	wdt_disable(); /* Turn the WDT off */
	307
	308	return NOTIFY_DONE;
	309	}
	310
	311	/*
	312	* Kernel Interfaces
	313	*/
	314
	315	static const struct file_operations wdt_fops = {
	316	.owner = THIS_MODULE,
	317	.llseek = no_llseek,
	318	.write = wdt_write,
	319	.unlocked_ioctl = wdt_ioctl,
	320	.open = wdt_open,
	321	.release = wdt_close,
	322	};
	323
	324	static struct miscdevice wdt_miscdev = {
	325	.minor = WATCHDOG_MINOR,
	326	.name = "watchdog",
	327	.fops = &wdt_fops,
	328	};
	329
	330	/*
	331	* The WDT needs to learn about soft shutdowns in order to
	332	* turn the timebomb registers off.
	333	*/
	334
	335	static struct notifier_block wdt_notifier = {
	336	.notifier_call = wdt_notify_sys,
	337	};
	338
	339	static int __init wdt_init(void)
	340	{
	341	int ret;
	342
27c766aa	343	pr_info("WDT driver for the Winbond(TM) W83697UG/UF Super I/O chip initialising\n");
7d8b0906 FF	344
	345	if (wdt_set_heartbeat(timeout)) {
	346	wdt_set_heartbeat(WATCHDOG_TIMEOUT);
27c766aa	347	pr_info("timeout value must be 1<=timeout<=255, using %d\n",
7d8b0906 FF	348	WATCHDOG_TIMEOUT);
	349	}
	350
	351	if (!request_region(wdt_io, 1, WATCHDOG_NAME)) {
27c766aa	352	pr_err("I/O address 0x%04x already in use\n", wdt_io);
7d8b0906 FF	353	ret = -EIO;
	354	goto out;
	355	}
	356
63bad145 EL	357	ret = w83697ug_init();
	358	if (ret != 0)
	359	goto unreg_regions;
7d8b0906 FF	360
	361	ret = register_reboot_notifier(&wdt_notifier);
	362	if (ret != 0) {
27c766aa	363	pr_err("cannot register reboot notifier (err=%d)\n", ret);
7d8b0906 FF	364	goto unreg_regions;
	365	}
	366
	367	ret = misc_register(&wdt_miscdev);
	368	if (ret != 0) {
27c766aa JP	369	pr_err("cannot register miscdev on minor=%d (err=%d)\n",
27c766aa JP	370	WATCHDOG_MINOR, ret);
7d8b0906 FF	371	goto unreg_reboot;
	372	}
	373
27c766aa	374	pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
7d8b0906 FF	375	timeout, nowayout);
	376
	377	out:
	378	return ret;
	379	unreg_reboot:
	380	unregister_reboot_notifier(&wdt_notifier);
	381	unreg_regions:
	382	release_region(wdt_io, 1);
	383	goto out;
	384	}
	385
	386	static void __exit wdt_exit(void)
	387	{
	388	misc_deregister(&wdt_miscdev);
	389	unregister_reboot_notifier(&wdt_notifier);
	390	release_region(wdt_io, 1);
	391	}
	392
	393	module_init(wdt_init);
	394	module_exit(wdt_exit);
	395
	396	MODULE_LICENSE("GPL");
	397	MODULE_AUTHOR("Flemming Frandsen <ff@nrvissing.net>");
	398	MODULE_DESCRIPTION("w83697ug/uf WDT driver");
	399	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);