[deliverable/linux.git] / drivers / char / watchdog / sbc60xxwdt.c

/*
 *	60xx Single Board Computer Watchdog Timer driver for Linux 2.2.x
 *
 *      Based on acquirewdt.c by Alan Cox.
 *
 *	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 author does 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 2000    Jakob Oestergaard <jakob@unthought.net>
 *
 *           12/4 - 2000      [Initial revision]
 *           25/4 - 2000      Added /dev/watchdog support
 *           09/5 - 2001      [smj@oro.net] fixed fop_write to "return 1" on success
 *           12/4 - 2002      [rob@osinvestor.com] eliminate fop_read
 *                            fix possible wdt_is_open race
 *                            add CONFIG_WATCHDOG_NOWAYOUT support
 *                            remove lock_kernel/unlock_kernel pairs
 *                            added KERN_* to printk's
 *                            got rid of extraneous comments
 *                            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
 *                            use module_param
 *                            made timeout (the emulated heartbeat) a module_param
 *                            made the keepalive ping an internal subroutine
 *                            made wdt_stop and wdt_start module params
 *                            added extra printk's for startup problems
 *                            added MODULE_AUTHOR and MODULE_DESCRIPTION info
 *
 *
 *  This WDT driver is different from the other Linux WDT
 *  drivers in the following ways:
 *  *)  The driver will ping the watchdog by itself, because this
 *      particular WDT has a very short timeout (one second) 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 "sbc60xxwdt"
#define PFX OUR_NAME ": "

/*
 * You must set these - The driver cannot probe for the settings
 */

static int wdt_stop = 0x45;
module_param(wdt_stop, int, 0);
MODULE_PARM_DESC(wdt_stop, "SBC60xx WDT 'stop' io port (default 0x45)");

static int wdt_start = 0x443;
module_param(wdt_start, int, 0);
MODULE_PARM_DESC(wdt_start, "SBC60xx WDT 'start' io port (default 0x443)");

/*
 * The 60xx board can use watchdog timeout values from one second
 * to several minutes.  The default is one second, so 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.
 * If the daemon pulses us every 25 seconds, we can still afford
 * a 5 second scheduling delay on the (high priority) daemon. That
 * should be sufficient for a box under any load.
 */

#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;

/*
 *	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 by reading from wdt_start */
		inb_p(wdt_start);
		/* Re-set the timer interval */
		mod_timer(&timer, jiffies + WDT_INTERVAL);
	} else {
		printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
	}
}

/*
 * Utility routines
 */

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

	/* Start the timer */
	mod_timer(&timer, jiffies + WDT_INTERVAL);
	printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
}

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

		/* Well, anyhow someone wrote to us, we should return that favour */
		wdt_keepalive();
	}
	return count;
}

static int fop_open(struct inode * inode, struct file * file)
{
	nonseekable_open(inode, file);

	/* Just in case we're already talking to someone... */
	if(test_and_set_bit(0, &wdt_is_open))
		return -EBUSY;

	if (nowayout)
		__module_get(THIS_MODULE);

	/* Good, fire up the show */
	wdt_startup();
	return 0;
}

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 = "SBC60xx",
	};

	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 sbc60xxwdt_unload(void)
{
	wdt_turnoff();

	/* Deregister */
	misc_deregister(&wdt_miscdev);

	unregister_reboot_notifier(&wdt_notifier);
	if ((wdt_stop != 0x45) && (wdt_stop != wdt_start))
		release_region(wdt_stop,1);
	release_region(wdt_start,1);
}

static int __init sbc60xxwdt_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(wdt_start, 1, "SBC 60XX WDT"))
	{
		printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
			wdt_start);
		rc = -EIO;
		goto err_out;
	}

	/* We cannot reserve 0x45 - the kernel already has! */
	if ((wdt_stop != 0x45) && (wdt_stop != wdt_start))
	{
		if (!request_region(wdt_stop, 1, "SBC 60XX WDT"))
		{
			printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
				wdt_stop);
			rc = -EIO;
			goto err_out_region1;
		}
	}

	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_region2;
	}

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

	printk(KERN_INFO PFX "WDT driver for 60XX single board computer initialised. timeout=%d sec (nowayout=%d)\n",
		timeout, nowayout);

	return 0;

err_out_miscdev:
	misc_deregister(&wdt_miscdev);
err_out_region2:
	if ((wdt_stop != 0x45) && (wdt_stop != wdt_start))
		release_region(wdt_stop,1);
err_out_region1:
	release_region(wdt_start,1);
err_out:
	return rc;
}

module_init(sbc60xxwdt_init);
module_exit(sbc60xxwdt_unload);

MODULE_AUTHOR("Jakob Oestergaard <jakob@unthought.net>");
MODULE_DESCRIPTION("60xx Single Board Computer Watchdog Timer driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* 60xx Single Board Computer Watchdog Timer driver for Linux 2.2.x
	3	*
	4	* Based on acquirewdt.c by Alan Cox.
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*
	11	* The author does NOT admit liability nor provide warranty for
	12	* any of this software. This material is provided "AS-IS" in
	13	* the hope that it may be useful for others.
	14	*
	15	* (c) Copyright 2000 Jakob Oestergaard <jakob@unthought.net>
	16	*
	17	* 12/4 - 2000 [Initial revision]
	18	* 25/4 - 2000 Added /dev/watchdog support
	19	* 09/5 - 2001 [smj@oro.net] fixed fop_write to "return 1" on success
	20	* 12/4 - 2002 [rob@osinvestor.com] eliminate fop_read
	21	* fix possible wdt_is_open race
	22	* add CONFIG_WATCHDOG_NOWAYOUT support
	23	* remove lock_kernel/unlock_kernel pairs
	24	* added KERN_* to printk's
	25	* got rid of extraneous comments
	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	* use module_param
	31	* made timeout (the emulated heartbeat) a module_param
	32	* made the keepalive ping an internal subroutine
	33	* made wdt_stop and wdt_start module params
	34	* added extra printk's for startup problems
	35	* added MODULE_AUTHOR and MODULE_DESCRIPTION info
	36	*
	37	*
	38	* This WDT driver is different from the other Linux WDT
	39	* drivers in the following ways:
	40	* *) The driver will ping the watchdog by itself, because this
	41	* particular WDT has a very short timeout (one second) and it
	42	* would be insane to count on any userspace daemon always
	43	* getting scheduled within that time frame.
	44	*
	45	*/
	46
	47	#include <linux/module.h>
	48	#include <linux/moduleparam.h>
	49	#include <linux/types.h>
	50	#include <linux/timer.h>
	51	#include <linux/jiffies.h>
	52	#include <linux/miscdevice.h>
	53	#include <linux/watchdog.h>
	54	#include <linux/fs.h>
	55	#include <linux/ioport.h>
	56	#include <linux/notifier.h>
	57	#include <linux/reboot.h>
	58	#include <linux/init.h>
	59
	60	#include <asm/io.h>
	61	#include <asm/uaccess.h>
	62	#include <asm/system.h>
	63
	64	#define OUR_NAME "sbc60xxwdt"
65	#define PFX OUR_NAME ": "
66
67	/*
68	* You must set these - The driver cannot probe for the settings
69	*/
70
71	static int wdt_stop = 0x45;
72	module_param(wdt_stop, int, 0);
73	MODULE_PARM_DESC(wdt_stop, "SBC60xx WDT 'stop' io port (default 0x45)");
74
75	static int wdt_start = 0x443;
76	module_param(wdt_start, int, 0);
77	MODULE_PARM_DESC(wdt_start, "SBC60xx WDT 'start' io port (default 0x443)");
78
79	/*
80	* The 60xx board can use watchdog timeout values from one second
81	* to several minutes. The default is one second, so if we reset
82	* the watchdog every ~250ms we should be safe.
83	*/
84
85	#define WDT_INTERVAL (HZ/4+1)
86
87	/*
88	* We must not require too good response from the userspace daemon.
89	* Here we require the userspace daemon to send us a heartbeat
90	* char to /dev/watchdog every 30 seconds.
91	* If the daemon pulses us every 25 seconds, we can still afford
92	* a 5 second scheduling delay on the (high priority) daemon. That
93	* should be sufficient for a box under any load.
94	*/
95
96	#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
97	static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
98	module_param(timeout, int, 0);
99	MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
100
4bfdf378	101	static int nowayout = WATCHDOG_NOWAYOUT;
1da177e4	102	module_param(nowayout, int, 0);
bffda5c8	103	MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
1da177e4 LT	104
1da177e4 LT	105	static void wdt_timer_ping(unsigned long);
82eb7c50	106	static DEFINE_TIMER(timer, wdt_timer_ping, 0, 0);
1da177e4 LT	107	static unsigned long next_heartbeat;
	108	static unsigned long wdt_is_open;
	109	static char wdt_expect_close;
	110
	111	/*
	112	* Whack the dog
	113	*/
	114
	115	static void wdt_timer_ping(unsigned long data)
	116	{
	117	/* If we got a heartbeat pulse within the WDT_US_INTERVAL
	118	* we agree to ping the WDT
	119	*/
	120	if(time_before(jiffies, next_heartbeat))
	121	{
	122	/* Ping the WDT by reading from wdt_start */
	123	inb_p(wdt_start);
	124	/* Re-set the timer interval */
82eb7c50	125	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4 LT	126	} else {
	127	printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n");
	128	}
	129	}
	130
	131	/*
	132	* Utility routines
	133	*/
	134
	135	static void wdt_startup(void)
	136	{
	137	next_heartbeat = jiffies + (timeout * HZ);
	138
	139	/* Start the timer */
82eb7c50	140	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4 LT	141	printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
	142	}
	143
	144	static void wdt_turnoff(void)
	145	{
	146	/* Stop the timer */
	147	del_timer(&timer);
	148	inb_p(wdt_stop);
	149	printk(KERN_INFO PFX "Watchdog timer is now disabled...\n");
	150	}
	151
	152	static void wdt_keepalive(void)
	153	{
	154	/* user land ping */
	155	next_heartbeat = jiffies + (timeout * HZ);
	156	}
	157
	158	/*
	159	* /dev/watchdog handling
	160	*/
	161
	162	static ssize_t fop_write(struct file * file, const char __user * buf, size_t count, loff_t * ppos)
	163	{
	164	/* See if we got the magic character 'V' and reload the timer */
	165	if(count)
	166	{
	167	if (!nowayout)
	168	{
	169	size_t ofs;
	170
	171	/* note: just in case someone wrote the magic character
	172	* five months ago... */
	173	wdt_expect_close = 0;
	174
	175	/* scan to see whether or not we got the magic character */
	176	for(ofs = 0; ofs != count; ofs++)
	177	{
	178	char c;
	179	if(get_user(c, buf+ofs))
	180	return -EFAULT;
	181	if(c == 'V')
	182	wdt_expect_close = 42;
	183	}
	184	}
	185
	186	/* Well, anyhow someone wrote to us, we should return that favour */
	187	wdt_keepalive();
	188	}
	189	return count;
	190	}
	191
	192	static int fop_open(struct inode * inode, struct file * file)
	193	{
	194	nonseekable_open(inode, file);
	195
	196	/* Just in case we're already talking to someone... */
	197	if(test_and_set_bit(0, &wdt_is_open))
	198	return -EBUSY;
	199
	200	if (nowayout)
	201	__module_get(THIS_MODULE);
	202
	203	/* Good, fire up the show */
	204	wdt_startup();
205	return 0;
206	}
207
208	static int fop_close(struct inode * inode, struct file * file)
209	{
210	if(wdt_expect_close == 42)
211	wdt_turnoff();
212	else {
213	del_timer(&timer);
214	printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n");
215	}
216	clear_bit(0, &wdt_is_open);
217	wdt_expect_close = 0;
218	return 0;
219	}
220
221	static int fop_ioctl(struct inode inode, struct file file, unsigned int cmd,
222	unsigned long arg)
223	{
224	void __user argp = (void __user )arg;
225	int __user *p = argp;
226	static struct watchdog_info ident=
227	{
228	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE,
229	.firmware_version = 1,
230	.identity = "SBC60xx",
231	};
232
233	switch(cmd)
234	{
235	default:
795b89d2	236	return -ENOTTY;
1da177e4 LT	237	case WDIOC_GETSUPPORT:
	238	return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0;
	239	case WDIOC_GETSTATUS:
	240	case WDIOC_GETBOOTSTATUS:
	241	return put_user(0, p);
	242	case WDIOC_KEEPALIVE:
	243	wdt_keepalive();
	244	return 0;
	245	case WDIOC_SETOPTIONS:
	246	{
	247	int new_options, retval = -EINVAL;
	248
	249	if(get_user(new_options, p))
	250	return -EFAULT;
	251
	252	if(new_options & WDIOS_DISABLECARD) {
	253	wdt_turnoff();
	254	retval = 0;
	255	}
	256
	257	if(new_options & WDIOS_ENABLECARD) {
	258	wdt_startup();
	259	retval = 0;
	260	}
	261
	262	return retval;
	263	}
	264	case WDIOC_SETTIMEOUT:
	265	{
	266	int new_timeout;
	267
	268	if(get_user(new_timeout, p))
	269	return -EFAULT;
	270
	271	if(new_timeout < 1 \|\| new_timeout > 3600) /* arbitrary upper limit */
	272	return -EINVAL;
	273
	274	timeout = new_timeout;
	275	wdt_keepalive();
	276	/* Fall through */
	277	}
	278	case WDIOC_GETTIMEOUT:
	279	return put_user(timeout, p);
	280	}
	281	}
	282
62322d25	283	static const struct file_operations wdt_fops = {
1da177e4 LT	284	.owner = THIS_MODULE,
	285	.llseek = no_llseek,
	286	.write = fop_write,
	287	.open = fop_open,
	288	.release = fop_close,
	289	.ioctl = fop_ioctl,
	290	};
	291
	292	static struct miscdevice wdt_miscdev = {
	293	.minor = WATCHDOG_MINOR,
	294	.name = "watchdog",
	295	.fops = &wdt_fops,
	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_turnoff();
	307	return NOTIFY_DONE;
	308	}
	309
	310	/*
	311	* The WDT needs to learn about soft shutdowns in order to
	312	* turn the timebomb registers off.
	313	*/
	314
	315	static struct notifier_block wdt_notifier=
	316	{
	317	.notifier_call = wdt_notify_sys,
	318	};
	319
	320	static void __exit sbc60xxwdt_unload(void)
	321	{
	322	wdt_turnoff();
	323
	324	/* Deregister */
	325	misc_deregister(&wdt_miscdev);
	326
	327	unregister_reboot_notifier(&wdt_notifier);
	328	if ((wdt_stop != 0x45) && (wdt_stop != wdt_start))
	329	release_region(wdt_stop,1);
	330	release_region(wdt_start,1);
	331	}
	332
	333	static int __init sbc60xxwdt_init(void)
	334	{
	335	int rc = -EBUSY;
	336
	337	if(timeout < 1 \|\| timeout > 3600) /* arbitrary upper limit */
	338	{
	339	timeout = WATCHDOG_TIMEOUT;
	340	printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n",
	341	timeout);
	342	}
	343
	344	if (!request_region(wdt_start, 1, "SBC 60XX WDT"))
	345	{
	346	printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
	347	wdt_start);
348	rc = -EIO;
349	goto err_out;
350	}
351
352	/* We cannot reserve 0x45 - the kernel already has! */
353	if ((wdt_stop != 0x45) && (wdt_stop != wdt_start))
354	{
355	if (!request_region(wdt_stop, 1, "SBC 60XX WDT"))
356	{
357	printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
358	wdt_stop);
359	rc = -EIO;
360	goto err_out_region1;
361	}
362	}
363
1da177e4 LT	364	rc = misc_register(&wdt_miscdev);
	365	if (rc)
	366	{
	367	printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
	368	wdt_miscdev.minor, rc);
	369	goto err_out_region2;
	370	}
	371
	372	rc = register_reboot_notifier(&wdt_notifier);
	373	if (rc)
	374	{
	375	printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
	376	rc);
	377	goto err_out_miscdev;
	378	}
	379
	380	printk(KERN_INFO PFX "WDT driver for 60XX single board computer initialised. timeout=%d sec (nowayout=%d)\n",
	381	timeout, nowayout);
	382
	383	return 0;
	384
	385	err_out_miscdev:
	386	misc_deregister(&wdt_miscdev);
	387	err_out_region2:
	388	if ((wdt_stop != 0x45) && (wdt_stop != wdt_start))
	389	release_region(wdt_stop,1);
	390	err_out_region1:
	391	release_region(wdt_start,1);
	392	err_out:
	393	return rc;
	394	}
	395
	396	module_init(sbc60xxwdt_init);
	397	module_exit(sbc60xxwdt_unload);
	398
	399	MODULE_AUTHOR("Jakob Oestergaard <jakob@unthought.net>");
	400	MODULE_DESCRIPTION("60xx Single Board Computer Watchdog Timer driver");
	401	MODULE_LICENSE("GPL");
	402	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);