[deliverable/linux.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 */
#define WATCHDOG_EARLY_DISABLE 1	/* Disable until userland kicks in */

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) ")");

static int early_disable = WATCHDOG_EARLY_DISABLE;
module_param(early_disable, int, 0);
MODULE_PARM_DESC(early_disable, "Watchdog gets disabled at boot time (default=" __MODULE_STRING(WATCHDOG_EARLY_DISABLE) ")");

/*
 *	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 unsigned char
wdt_running(void)
{
	unsigned char t;

	spin_lock(&io_lock);
	w83697hf_select_wdt();

	t = w83697hf_get_reg(0xF4);	/* Read timer */

	w83697hf_deselect_wdt();
	spin_unlock(&io_lock);

	return t;
}

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();
	if (early_disable) {
		if (wdt_running())
			printk (KERN_WARNING PFX "Stopping previously enabled watchdog until userland kicks in\n");
		wdt_disable();
	}

	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 ": "
f9a8c891 MJ	46	#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
6fd65601	47	#define WATCHDOG_EARLY_DISABLE 1 /* Disable until userland kicks in */
f9a8c891 MJ	48
	49	static unsigned long wdt_is_open;
	50	static char expect_close;
c7dfd0cc	51	static DEFINE_SPINLOCK(io_lock);
f9a8c891 MJ	52
f9a8c891 MJ	53	/* You must set this - there is no sane way to probe for this board. */
c81b2996	54	static int wdt_io = 0x2e;
f9a8c891	55	module_param(wdt_io, int, 0);
c81b2996	56	MODULE_PARM_DESC(wdt_io, "w83697hf/hg WDT io port (default 0x2e, 0 = autodetect)");
f9a8c891 MJ	57
	58	static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
	59	module_param(timeout, int, 0);
5794a9f4	60	MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255 (default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
f9a8c891 MJ	61
	62	static int nowayout = WATCHDOG_NOWAYOUT;
	63	module_param(nowayout, int, 0);
bffda5c8	64	MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
f9a8c891	65
6fd65601 ST	66	static int early_disable = WATCHDOG_EARLY_DISABLE;
	67	module_param(early_disable, int, 0);
	68	MODULE_PARM_DESC(early_disable, "Watchdog gets disabled at boot time (default=" __MODULE_STRING(WATCHDOG_EARLY_DISABLE) ")");
	69
f9a8c891 MJ	70	/*
	71	* Kernel methods.
	72	*/
	73
44d7d328 ST	74	#define W83697HF_EFER (wdt_io+0) /* Extended Function Enable Register */
	75	#define W83697HF_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */
	76	#define W83697HF_EFDR (wdt_io+1) /* Extended Function Data Register */
f9a8c891	77
f7be3328 ST	78	static inline void
f7be3328 ST	79	w83697hf_unlock(void)
f9a8c891	80	{
44d7d328 ST	81	outb_p(0x87, W83697HF_EFER); /* Enter extended function mode */
44d7d328 ST	82	outb_p(0x87, W83697HF_EFER); /* Again according to manual */
f7be3328 ST	83	}
f7be3328 ST	84
fe851eba ST	85	static inline void
	86	w83697hf_lock(void)
	87	{
	88	outb_p(0xAA, W83697HF_EFER); /* Leave extended function mode */
	89	}
	90
0cd54476	91	/*
d46ab596 ST	92	* The three functions w83697hf_get_reg(), w83697hf_set_reg() and
d46ab596 ST	93	* w83697hf_write_timeout() must be called with the device unlocked.
0cd54476 ST	94	*/
	95
	96	static unsigned char
	97	w83697hf_get_reg(unsigned char reg)
	98	{
	99	outb_p(reg, W83697HF_EFIR);
	100	return inb_p(W83697HF_EFDR);
	101	}
	102
	103	static void
	104	w83697hf_set_reg(unsigned char reg, unsigned char data)
	105	{
	106	outb_p(reg, W83697HF_EFIR);
	107	outb_p(data, W83697HF_EFDR);
	108	}
	109
d46ab596 ST	110	static void
	111	w83697hf_write_timeout(int timeout)
	112	{
	113	w83697hf_set_reg(0xF4, timeout); /* Write Timeout counter to CRF4 */
	114	}
	115
a7933e05 ST	116	static void
	117	w83697hf_select_wdt(void)
	118	{
	119	w83697hf_unlock();
	120	w83697hf_set_reg(0x07, 0x08); /* Switch to logic device 8 (GPIO2) */
	121	}
	122
	123	static inline void
	124	w83697hf_deselect_wdt(void)
	125	{
	126	w83697hf_lock();
	127	}
	128
f9a8c891 MJ	129	static void
	130	w83697hf_init(void)
	131	{
b7b9868b	132	unsigned char bbuf;
f9a8c891	133
fa69afd3 ST	134	w83697hf_select_wdt();
fa69afd3 ST	135
b7b9868b ST	136	bbuf = w83697hf_get_reg(0x29);
	137	bbuf &= ~0x60;
	138	bbuf \|= 0x20;
	139	w83697hf_set_reg(0x29, bbuf); /* Set pin 119 to WDTO# mode (= CR29, WDT0) */
f9a8c891	140
b7b9868b ST	141	bbuf = w83697hf_get_reg(0xF3);
	142	bbuf &= ~0x04;
	143	w83697hf_set_reg(0xF3, bbuf); /* Count mode is seconds */
f9a8c891	144
fa69afd3	145	w83697hf_deselect_wdt();
f9a8c891 MJ	146	}
f9a8c891 MJ	147
03315adc	148	static void
089d8139	149	wdt_ping(void)
f9a8c891	150	{
ab9d4414	151	spin_lock(&io_lock);
a7933e05	152	w83697hf_select_wdt();
f9a8c891	153
d46ab596	154	w83697hf_write_timeout(timeout);
f9a8c891	155
a7933e05	156	w83697hf_deselect_wdt();
ab9d4414	157	spin_unlock(&io_lock);
f9a8c891 MJ	158	}
f9a8c891 MJ	159
03315adc	160	static void
089d8139	161	wdt_enable(void)
f9a8c891	162	{
089d8139 ST	163	spin_lock(&io_lock);
	164	w83697hf_select_wdt();
	165
	166	w83697hf_write_timeout(timeout);
	167	w83697hf_set_reg(0x30, 1); /* Enable timer */
	168
	169	w83697hf_deselect_wdt();
	170	spin_unlock(&io_lock);
f9a8c891 MJ	171	}
f9a8c891 MJ	172
03315adc	173	static void
f9a8c891 MJ	174	wdt_disable(void)
f9a8c891 MJ	175	{
089d8139 ST	176	spin_lock(&io_lock);
	177	w83697hf_select_wdt();
	178
	179	w83697hf_set_reg(0x30, 0); /* Disable timer */
	180	w83697hf_write_timeout(0);
	181
	182	w83697hf_deselect_wdt();
	183	spin_unlock(&io_lock);
f9a8c891 MJ	184	}
f9a8c891 MJ	185
6fd65601 ST	186	static unsigned char
	187	wdt_running(void)
	188	{
	189	unsigned char t;
	190
	191	spin_lock(&io_lock);
	192	w83697hf_select_wdt();
	193
	194	t = w83697hf_get_reg(0xF4); /* Read timer */
	195
	196	w83697hf_deselect_wdt();
	197	spin_unlock(&io_lock);
	198
	199	return t;
	200	}
	201
f9a8c891 MJ	202	static int
	203	wdt_set_heartbeat(int t)
	204	{
eb64419e	205	if ((t < 1) \|\| (t > 255))
f9a8c891 MJ	206	return -EINVAL;
	207
	208	timeout = t;
	209	return 0;
	210	}
	211
	212	static ssize_t
	213	wdt_write(struct file file, const char __user buf, size_t count, loff_t *ppos)
	214	{
	215	if (count) {
	216	if (!nowayout) {
	217	size_t i;
	218
	219	expect_close = 0;
	220
	221	for (i = 0; i != count; i++) {
	222	char c;
	223	if (get_user(c, buf+i))
	224	return -EFAULT;
	225	if (c == 'V')
	226	expect_close = 42;
	227	}
	228	}
	229	wdt_ping();
	230	}
	231	return count;
	232	}
	233
	234	static int
	235	wdt_ioctl(struct inode inode, struct file file, unsigned int cmd,
	236	unsigned long arg)
	237	{
	238	void __user argp = (void __user )arg;
	239	int __user *p = argp;
	240	int new_timeout;
	241	static struct watchdog_info ident = {
	242	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT \| WDIOF_MAGICCLOSE,
	243	.firmware_version = 1,
	244	.identity = "W83697HF WDT",
	245	};
	246
	247	switch (cmd) {
	248	case WDIOC_GETSUPPORT:
db16525e ST	249	if (copy_to_user(argp, &ident, sizeof(ident)))
	250	return -EFAULT;
	251	break;
f9a8c891 MJ	252
	253	case WDIOC_GETSTATUS:
	254	case WDIOC_GETBOOTSTATUS:
db16525e	255	return put_user(0, p);
f9a8c891 MJ	256
f9a8c891 MJ	257	case WDIOC_KEEPALIVE:
db16525e ST	258	wdt_ping();
db16525e ST	259	break;
f9a8c891 MJ	260
f9a8c891 MJ	261	case WDIOC_SETTIMEOUT:
db16525e ST	262	if (get_user(new_timeout, p))
	263	return -EFAULT;
	264	if (wdt_set_heartbeat(new_timeout))
	265	return -EINVAL;
	266	wdt_ping();
	267	/* Fall */
f9a8c891 MJ	268
f9a8c891 MJ	269	case WDIOC_GETTIMEOUT:
db16525e	270	return put_user(timeout, p);
f9a8c891 MJ	271
	272	case WDIOC_SETOPTIONS:
	273	{
db16525e	274	int options, retval = -EINVAL;
f9a8c891	275
db16525e ST	276	if (get_user(options, p))
db16525e ST	277	return -EFAULT;
f9a8c891	278
db16525e ST	279	if (options & WDIOS_DISABLECARD) {
	280	wdt_disable();
	281	retval = 0;
	282	}
f9a8c891	283
db16525e	284	if (options & WDIOS_ENABLECARD) {
089d8139	285	wdt_enable();
db16525e ST	286	retval = 0;
db16525e ST	287	}
f9a8c891	288
db16525e	289	return retval;
f9a8c891 MJ	290	}
	291
	292	default:
db16525e	293	return -ENOTTY;
f9a8c891 MJ	294	}
	295	return 0;
	296	}
	297
	298	static int
	299	wdt_open(struct inode inode, struct file file)
	300	{
	301	if (test_and_set_bit(0, &wdt_is_open))
	302	return -EBUSY;
	303	/*
	304	* Activate
	305	*/
	306
089d8139	307	wdt_enable();
f9a8c891 MJ	308	return nonseekable_open(inode, file);
	309	}
	310
	311	static int
	312	wdt_close(struct inode inode, struct file file)
	313	{
	314	if (expect_close == 42) {
	315	wdt_disable();
	316	} else {
db16525e	317	printk (KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
f9a8c891 MJ	318	wdt_ping();
	319	}
	320	expect_close = 0;
	321	clear_bit(0, &wdt_is_open);
	322	return 0;
	323	}
	324
	325	/*
	326	* Notifier for system down
	327	*/
	328
	329	static int
	330	wdt_notify_sys(struct notifier_block *this, unsigned long code,
	331	void *unused)
	332	{
	333	if (code == SYS_DOWN \|\| code == SYS_HALT) {
	334	/* Turn the WDT off */
	335	wdt_disable();
	336	}
	337	return NOTIFY_DONE;
	338	}
	339
	340	/*
	341	* Kernel Interfaces
	342	*/
	343
2b8693c0	344	static const struct file_operations wdt_fops = {
f9a8c891 MJ	345	.owner = THIS_MODULE,
	346	.llseek = no_llseek,
	347	.write = wdt_write,
	348	.ioctl = wdt_ioctl,
	349	.open = wdt_open,
	350	.release = wdt_close,
	351	};
	352
	353	static struct miscdevice wdt_miscdev = {
	354	.minor = WATCHDOG_MINOR,
	355	.name = "watchdog",
	356	.fops = &wdt_fops,
	357	};
	358
	359	/*
	360	* The WDT needs to learn about soft shutdowns in order to
	361	* turn the timebomb registers off.
	362	*/
	363
	364	static struct notifier_block wdt_notifier = {
	365	.notifier_call = wdt_notify_sys,
	366	};
	367
c81b2996 ST	368	static int
	369	w83697hf_check_wdt(void)
	370	{
	371	if (!request_region(wdt_io, 2, WATCHDOG_NAME)) {
	372	printk (KERN_ERR PFX "I/O address 0x%x already in use\n", wdt_io);
	373	return -EIO;
	374	}
	375
	376	printk (KERN_DEBUG PFX "Looking for watchdog at address 0x%x\n", wdt_io);
	377	w83697hf_unlock();
	378	if (w83697hf_get_reg(0x20) == 0x60) {
	379	printk (KERN_INFO PFX "watchdog found at address 0x%x\n", wdt_io);
	380	w83697hf_lock();
	381	return 0;
	382	}
	383	w83697hf_lock(); /* Reprotect in case it was a compatible device */
	384
	385	printk (KERN_INFO PFX "watchdog not found at address 0x%x\n", wdt_io);
	386	release_region(wdt_io, 2);
	387	return -EIO;
	388	}
	389
e223f01a WVS	390	static int w83697hf_ioports[] = { 0x2e, 0x4e, 0x00 };
e223f01a WVS	391
f9a8c891 MJ	392	static int __init
	393	wdt_init(void)
	394	{
e223f01a	395	int ret, i, found = 0;
f9a8c891	396
de710d68	397	printk (KERN_INFO PFX "WDT driver for W83697HF/HG initializing\n");
f9a8c891	398
e223f01a WVS	399	if (wdt_io == 0) {
	400	/* we will autodetect the W83697HF/HG watchdog */
	401	for (i = 0; ((!found) && (w83697hf_ioports[i] != 0)); i++) {
	402	wdt_io = w83697hf_ioports[i];
cde10ba3	403	if (!w83697hf_check_wdt())
e223f01a WVS	404	found++;
	405	}
	406	} else {
c81b2996	407	if (!w83697hf_check_wdt())
e223f01a	408	found++;
c81b2996 ST	409	}
c81b2996 ST	410
e223f01a WVS	411	if (!found) {
	412	printk (KERN_ERR PFX "No W83697HF/HG could be found\n");
	413	ret = -EIO;
	414	goto out;
	415	}
c81b2996	416
fa69afd3	417	w83697hf_init();
6fd65601 ST	418	if (early_disable) {
	419	if (wdt_running())
	420	printk (KERN_WARNING PFX "Stopping previously enabled watchdog until userland kicks in\n");
	421	wdt_disable();
	422	}
c81b2996	423
f9a8c891 MJ	424	if (wdt_set_heartbeat(timeout)) {
f9a8c891 MJ	425	wdt_set_heartbeat(WATCHDOG_TIMEOUT);
eb64419e	426	printk (KERN_INFO PFX "timeout value must be 1<=timeout<=255, using %d\n",
f9a8c891 MJ	427	WATCHDOG_TIMEOUT);
	428	}
	429
f9a8c891 MJ	430	ret = register_reboot_notifier(&wdt_notifier);
	431	if (ret != 0) {
	432	printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
	433	ret);
	434	goto unreg_regions;
	435	}
	436
	437	ret = misc_register(&wdt_miscdev);
	438	if (ret != 0) {
	439	printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
	440	WATCHDOG_MINOR, ret);
	441	goto unreg_reboot;
	442	}
	443
	444	printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
	445	timeout, nowayout);
	446
	447	out:
	448	return ret;
	449	unreg_reboot:
	450	unregister_reboot_notifier(&wdt_notifier);
	451	unreg_regions:
b41a9f59	452	release_region(wdt_io, 2);
f9a8c891 MJ	453	goto out;
	454	}
	455
	456	static void __exit
	457	wdt_exit(void)
	458	{
	459	misc_deregister(&wdt_miscdev);
	460	unregister_reboot_notifier(&wdt_notifier);
b41a9f59	461	release_region(wdt_io, 2);
f9a8c891 MJ	462	}
	463
	464	module_init(wdt_init);
	465	module_exit(wdt_exit);
	466
	467	MODULE_LICENSE("GPL");
3fdee8db	468	MODULE_AUTHOR("Marcus Junker <junker@anduras.de>, Samuel Tardieu <sam@rfc1149.net>");
de710d68	469	MODULE_DESCRIPTION("w83697hf/hg WDT driver");
f9a8c891	470	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);