[deliverable/linux.git] / drivers / watchdog / alim7101_wdt.c

/*
 *	ALi M7101 PMU Computer Watchdog Timer driver
 *
 *	Based on w83877f_wdt.c by Scott Jennings <linuxdrivers@oro.net>
 *	and the Cobalt kernel WDT timer driver by Tim Hockin
 *	                                      <thockin@cobaltnet.com>
 *
 *	(c)2002 Steve Hill <steve@navaho.co.uk>
 *
 *  This WDT driver is different from most other Linux WDT
 *  drivers in that the driver will ping the watchdog by itself,
 *  because this particular WDT has a very short timeout (1.6
 *  seconds) and it would be insane to count on any userspace
 *  daemon always getting scheduled within that time frame.
 *
 *  Additions:
 *   Aug 23, 2004 - Added use_gpio module parameter for use on revision a1d PMUs
 *                  found on very old cobalt hardware.
 *                  -- Mike Waychison <michael.waychison@sun.com>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/ioport.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/uaccess.h>

#include <asm/system.h>

#define WDT_ENABLE 0x9C
#define WDT_DISABLE 0x8C

#define ALI_7101_WDT    0x92
#define ALI_7101_GPIO   0x7D
#define ALI_7101_GPIO_O 0x7E
#define ALI_WDT_ARM     0x01

/*
 * We're going to use a 1 second timeout.
 * 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.
 */

#define WATCHDOG_TIMEOUT 30            /* 30 sec default timeout */
/* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
static int timeout = WATCHDOG_TIMEOUT;
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout,
		"Watchdog timeout in seconds. (1<=timeout<=3600, default="
				__MODULE_STRING(WATCHDOG_TIMEOUT) ")");

static int use_gpio; /* Use the pic (for a1d revision alim7101) */
module_param(use_gpio, int, 0);
MODULE_PARM_DESC(use_gpio,
		"Use the gpio watchdog (required by old cobalt boards).");

static void wdt_timer_ping(unsigned long);
static DEFINE_TIMER(timer, wdt_timer_ping, 0, 1);
static unsigned long next_heartbeat;
static unsigned long wdt_is_open;
static char wdt_expect_close;
static struct pci_dev *alim7101_pmu;

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) ")");

/*
 *	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
	 */
	char tmp;

	if (time_before(jiffies, next_heartbeat)) {
		/* Ping the WDT (this is actually a disarm/arm sequence) */
		pci_read_config_byte(alim7101_pmu, 0x92, &tmp);
		pci_write_config_byte(alim7101_pmu,
					ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
		pci_write_config_byte(alim7101_pmu,
					ALI_7101_WDT, (tmp | ALI_WDT_ARM));
		if (use_gpio) {
			pci_read_config_byte(alim7101_pmu,
					ALI_7101_GPIO_O, &tmp);
			pci_write_config_byte(alim7101_pmu,
					ALI_7101_GPIO_O, tmp | 0x20);
			pci_write_config_byte(alim7101_pmu,
					ALI_7101_GPIO_O, tmp & ~0x20);
		}
	} else {
		pr_warn("Heartbeat lost! Will not ping the watchdog\n");
	}
	/* Re-set the timer interval */
	mod_timer(&timer, jiffies + WDT_INTERVAL);
}

/*
 * Utility routines
 */

static void wdt_change(int writeval)
{
	char tmp;

	pci_read_config_byte(alim7101_pmu, ALI_7101_WDT, &tmp);
	if (writeval == WDT_ENABLE) {
		pci_write_config_byte(alim7101_pmu,
					ALI_7101_WDT, (tmp | ALI_WDT_ARM));
		if (use_gpio) {
			pci_read_config_byte(alim7101_pmu,
					ALI_7101_GPIO_O, &tmp);
			pci_write_config_byte(alim7101_pmu,
					ALI_7101_GPIO_O, tmp & ~0x20);
		}

	} else {
		pci_write_config_byte(alim7101_pmu,
					ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
		if (use_gpio) {
			pci_read_config_byte(alim7101_pmu,
					ALI_7101_GPIO_O, &tmp);
			pci_write_config_byte(alim7101_pmu,
					ALI_7101_GPIO_O, tmp | 0x20);
		}
	}
}

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

	/* We must enable before we kick off the timer in case the timer
	   occurs as we ping it */

	wdt_change(WDT_ENABLE);

	/* Start the timer */
	mod_timer(&timer, jiffies + WDT_INTERVAL);

	pr_info("Watchdog timer is now enabled\n");
}

static void wdt_turnoff(void)
{
	/* Stop the timer */
	del_timer_sync(&timer);
	wdt_change(WDT_DISABLE);
	pr_info("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;

			/* now scan */
			for (ofs = 0; ofs != count; ofs++) {
				char c;
				if (get_user(c, buf + ofs))
					return -EFAULT;
				if (c == 'V')
					wdt_expect_close = 42;
			}
		}
		/* someone wrote to us, we should restart timer */
		wdt_keepalive();
	}
	return count;
}

static int fop_open(struct inode *inode, struct file *file)
{
	/* Just in case we're already talking to someone... */
	if (test_and_set_bit(0, &wdt_is_open))
		return -EBUSY;
	/* Good, fire up the show */
	wdt_startup();
	return nonseekable_open(inode, file);
}

static int fop_close(struct inode *inode, struct file *file)
{
	if (wdt_expect_close == 42)
		wdt_turnoff();
	else {
		/* wim: shouldn't there be a: del_timer(&timer); */
		pr_crit("device file closed unexpectedly. Will not stop the WDT!\n");
	}
	clear_bit(0, &wdt_is_open);
	wdt_expect_close = 0;
	return 0;
}

static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	static const struct watchdog_info ident = {
		.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT
							| WDIOF_MAGICCLOSE,
		.firmware_version = 1,
		.identity = "ALiM7101",
	};

	switch (cmd) {
	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_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_KEEPALIVE:
		wdt_keepalive();
		return 0;
	case WDIOC_SETTIMEOUT:
	{
		int new_timeout;

		if (get_user(new_timeout, p))
			return -EFAULT;
		/* arbitrary upper limit */
		if (new_timeout < 1 || new_timeout > 3600)
			return -EINVAL;
		timeout = new_timeout;
		wdt_keepalive();
		/* Fall through */
	}
	case WDIOC_GETTIMEOUT:
		return put_user(timeout, p);
	default:
		return -ENOTTY;
	}
}

static const struct file_operations wdt_fops = {
	.owner		=	THIS_MODULE,
	.llseek		=	no_llseek,
	.write		=	fop_write,
	.open		=	fop_open,
	.release	=	fop_close,
	.unlocked_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();

	if (code == SYS_RESTART) {
		/*
		 * Cobalt devices have no way of rebooting themselves other
		 * than getting the watchdog to pull reset, so we restart the
		 * watchdog on reboot with no heartbeat
		 */
		wdt_change(WDT_ENABLE);
		pr_info("Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second\n");
	}
	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 alim7101_wdt_unload(void)
{
	wdt_turnoff();
	/* Deregister */
	misc_deregister(&wdt_miscdev);
	unregister_reboot_notifier(&wdt_notifier);
	pci_dev_put(alim7101_pmu);
}

static int __init alim7101_wdt_init(void)
{
	int rc = -EBUSY;
	struct pci_dev *ali1543_south;
	char tmp;

	pr_info("Steve Hill <steve@navaho.co.uk>\n");
	alim7101_pmu = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101,
		NULL);
	if (!alim7101_pmu) {
		pr_info("ALi M7101 PMU not present - WDT not set\n");
		return -EBUSY;
	}

	/* Set the WDT in the PMU to 1 second */
	pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, 0x02);

	ali1543_south = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533,
		NULL);
	if (!ali1543_south) {
		pr_info("ALi 1543 South-Bridge not present - WDT not set\n");
		goto err_out;
	}
	pci_read_config_byte(ali1543_south, 0x5e, &tmp);
	pci_dev_put(ali1543_south);
	if ((tmp & 0x1e) == 0x00) {
		if (!use_gpio) {
			pr_info("Detected old alim7101 revision 'a1d'.  If this is a cobalt board, set the 'use_gpio' module parameter.\n");
			goto err_out;
		}
		nowayout = 1;
	} else if ((tmp & 0x1e) != 0x12 && (tmp & 0x1e) != 0x00) {
		pr_info("ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n");
		goto err_out;
	}

	if (timeout < 1 || timeout > 3600) {
		/* arbitrary upper limit */
		timeout = WATCHDOG_TIMEOUT;
		pr_info("timeout value must be 1 <= x <= 3600, using %d\n",
			timeout);
	}

	rc = register_reboot_notifier(&wdt_notifier);
	if (rc) {
		pr_err("cannot register reboot notifier (err=%d)\n", rc);
		goto err_out;
	}

	rc = misc_register(&wdt_miscdev);
	if (rc) {
		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
		       wdt_miscdev.minor, rc);
		goto err_out_reboot;
	}

	if (nowayout)
		__module_get(THIS_MODULE);

	pr_info("WDT driver for ALi M7101 initialised. timeout=%d sec (nowayout=%d)\n",
		timeout, nowayout);
	return 0;

err_out_reboot:
	unregister_reboot_notifier(&wdt_notifier);
err_out:
	pci_dev_put(alim7101_pmu);
	return rc;
}

module_init(alim7101_wdt_init);
module_exit(alim7101_wdt_unload);

static DEFINE_PCI_DEVICE_TABLE(alim7101_pci_tbl) __used = {
	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533) },
	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
	{ }
};

MODULE_DEVICE_TABLE(pci, alim7101_pci_tbl);

MODULE_AUTHOR("Steve Hill");
MODULE_DESCRIPTION("ALi M7101 PMU Computer Watchdog Timer driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* ALi M7101 PMU Computer Watchdog Timer driver
	3	*
	4	* Based on w83877f_wdt.c by Scott Jennings <linuxdrivers@oro.net>
	5	* and the Cobalt kernel WDT timer driver by Tim Hockin
	6	* <thockin@cobaltnet.com>
	7	*
	8	* (c)2002 Steve Hill <steve@navaho.co.uk>
	9	*
	10	* This WDT driver is different from most other Linux WDT
	11	* drivers in that the driver will ping the watchdog by itself,
	12	* because this particular WDT has a very short timeout (1.6
	13	* seconds) and it would be insane to count on any userspace
	14	* daemon always getting scheduled within that time frame.
	15	*
	16	* Additions:
	17	* Aug 23, 2004 - Added use_gpio module parameter for use on revision a1d PMUs
	18	* found on very old cobalt hardware.
	19	* -- Mike Waychison <michael.waychison@sun.com>
	20	*/
	21
27c766aa JP	22	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27c766aa JP	23
1da177e4 LT	24	#include <linux/module.h>
	25	#include <linux/moduleparam.h>
	26	#include <linux/types.h>
	27	#include <linux/timer.h>
	28	#include <linux/miscdevice.h>
	29	#include <linux/watchdog.h>
	30	#include <linux/ioport.h>
	31	#include <linux/notifier.h>
	32	#include <linux/reboot.h>
	33	#include <linux/init.h>
	34	#include <linux/fs.h>
	35	#include <linux/pci.h>
173d95bc AC	36	#include <linux/io.h>
173d95bc AC	37	#include <linux/uaccess.h>
089ab079	38
1da177e4 LT	39	#include <asm/system.h>
1da177e4 LT	40
1da177e4 LT	41	#define WDT_ENABLE 0x9C
	42	#define WDT_DISABLE 0x8C
	43
	44	#define ALI_7101_WDT 0x92
	45	#define ALI_7101_GPIO 0x7D
	46	#define ALI_7101_GPIO_O 0x7E
	47	#define ALI_WDT_ARM 0x01
	48
	49	/*
	50	* We're going to use a 1 second timeout.
	51	* If we reset the watchdog every ~250ms we should be safe. */
	52
	53	#define WDT_INTERVAL (HZ/4+1)
	54
	55	/*
	56	* We must not require too good response from the userspace daemon.
	57	* Here we require the userspace daemon to send us a heartbeat
	58	* char to /dev/watchdog every 30 seconds.
	59	*/
	60
	61	#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
173d95bc AC	62	/* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
173d95bc AC	63	static int timeout = WATCHDOG_TIMEOUT;
1da177e4	64	module_param(timeout, int, 0);
173d95bc AC	65	MODULE_PARM_DESC(timeout,
	66	"Watchdog timeout in seconds. (1<=timeout<=3600, default="
	67	__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
1da177e4	68
173d95bc	69	static int use_gpio; /* Use the pic (for a1d revision alim7101) */
1da177e4	70	module_param(use_gpio, int, 0);
173d95bc AC	71	MODULE_PARM_DESC(use_gpio,
173d95bc AC	72	"Use the gpio watchdog (required by old cobalt boards).");
1da177e4 LT	73
1da177e4 LT	74	static void wdt_timer_ping(unsigned long);
82eb7c50	75	static DEFINE_TIMER(timer, wdt_timer_ping, 0, 1);
1da177e4 LT	76	static unsigned long next_heartbeat;
	77	static unsigned long wdt_is_open;
	78	static char wdt_expect_close;
	79	static struct pci_dev *alim7101_pmu;
	80
86a1e189 WVS	81	static bool nowayout = WATCHDOG_NOWAYOUT;
86a1e189 WVS	82	module_param(nowayout, bool, 0);
173d95bc AC	83	MODULE_PARM_DESC(nowayout,
	84	"Watchdog cannot be stopped once started (default="
	85	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
1da177e4 LT	86
	87	/*
	88	* Whack the dog
	89	*/
	90
	91	static void wdt_timer_ping(unsigned long data)
	92	{
	93	/* If we got a heartbeat pulse within the WDT_US_INTERVAL
	94	* we agree to ping the WDT
	95	*/
173d95bc	96	char tmp;
1da177e4	97
173d95bc	98	if (time_before(jiffies, next_heartbeat)) {
1da177e4 LT	99	/* Ping the WDT (this is actually a disarm/arm sequence) */
1da177e4 LT	100	pci_read_config_byte(alim7101_pmu, 0x92, &tmp);
173d95bc AC	101	pci_write_config_byte(alim7101_pmu,
	102	ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
	103	pci_write_config_byte(alim7101_pmu,
	104	ALI_7101_WDT, (tmp \| ALI_WDT_ARM));
1da177e4	105	if (use_gpio) {
173d95bc AC	106	pci_read_config_byte(alim7101_pmu,
	107	ALI_7101_GPIO_O, &tmp);
	108	pci_write_config_byte(alim7101_pmu,
	109	ALI_7101_GPIO_O, tmp \| 0x20);
	110	pci_write_config_byte(alim7101_pmu,
	111	ALI_7101_GPIO_O, tmp & ~0x20);
1da177e4 LT	112	}
1da177e4 LT	113	} else {
27c766aa	114	pr_warn("Heartbeat lost! Will not ping the watchdog\n");
1da177e4 LT	115	}
1da177e4 LT	116	/* Re-set the timer interval */
82eb7c50	117	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4 LT	118	}
	119
	120	/*
	121	* Utility routines
	122	*/
	123
	124	static void wdt_change(int writeval)
	125	{
7944d3a5	126	char tmp;
1da177e4 LT	127
	128	pci_read_config_byte(alim7101_pmu, ALI_7101_WDT, &tmp);
	129	if (writeval == WDT_ENABLE) {
173d95bc AC	130	pci_write_config_byte(alim7101_pmu,
173d95bc AC	131	ALI_7101_WDT, (tmp \| ALI_WDT_ARM));
1da177e4	132	if (use_gpio) {
173d95bc AC	133	pci_read_config_byte(alim7101_pmu,
	134	ALI_7101_GPIO_O, &tmp);
	135	pci_write_config_byte(alim7101_pmu,
	136	ALI_7101_GPIO_O, tmp & ~0x20);
1da177e4 LT	137	}
	138
	139	} else {
173d95bc AC	140	pci_write_config_byte(alim7101_pmu,
173d95bc AC	141	ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
1da177e4	142	if (use_gpio) {
173d95bc AC	143	pci_read_config_byte(alim7101_pmu,
	144	ALI_7101_GPIO_O, &tmp);
	145	pci_write_config_byte(alim7101_pmu,
	146	ALI_7101_GPIO_O, tmp \| 0x20);
1da177e4 LT	147	}
	148	}
	149	}
	150
	151	static void wdt_startup(void)
	152	{
	153	next_heartbeat = jiffies + (timeout * HZ);
	154
	155	/* We must enable before we kick off the timer in case the timer
	156	occurs as we ping it */
	157
	158	wdt_change(WDT_ENABLE);
	159
	160	/* Start the timer */
82eb7c50	161	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4	162
27c766aa	163	pr_info("Watchdog timer is now enabled\n");
1da177e4 LT	164	}
	165
	166	static void wdt_turnoff(void)
	167	{
	168	/* Stop the timer */
	169	del_timer_sync(&timer);
	170	wdt_change(WDT_DISABLE);
27c766aa	171	pr_info("Watchdog timer is now disabled...\n");
1da177e4 LT	172	}
	173
	174	static void wdt_keepalive(void)
	175	{
	176	/* user land ping */
	177	next_heartbeat = jiffies + (timeout * HZ);
	178	}
	179
	180	/*
	181	* /dev/watchdog handling
	182	*/
	183
173d95bc AC	184	static ssize_t fop_write(struct file file, const char __user buf,
173d95bc AC	185	size_t count, loff_t *ppos)
1da177e4 LT	186	{
1da177e4 LT	187	/* See if we got the magic character 'V' and reload the timer */
173d95bc	188	if (count) {
1da177e4 LT	189	if (!nowayout) {
	190	size_t ofs;
	191
	192	/* note: just in case someone wrote the magic character
	193	* five months ago... */
	194	wdt_expect_close = 0;
	195
	196	/* now scan */
	197	for (ofs = 0; ofs != count; ofs++) {
	198	char c;
7944d3a5	199	if (get_user(c, buf + ofs))
1da177e4 LT	200	return -EFAULT;
	201	if (c == 'V')
	202	wdt_expect_close = 42;
	203	}
	204	}
	205	/* someone wrote to us, we should restart timer */
	206	wdt_keepalive();
	207	}
	208	return count;
	209	}
	210
173d95bc	211	static int fop_open(struct inode inode, struct file file)
1da177e4 LT	212	{
1da177e4 LT	213	/* Just in case we're already talking to someone... */
173d95bc	214	if (test_and_set_bit(0, &wdt_is_open))
1da177e4 LT	215	return -EBUSY;
	216	/* Good, fire up the show */
	217	wdt_startup();
	218	return nonseekable_open(inode, file);
	219	}
	220
173d95bc	221	static int fop_close(struct inode inode, struct file file)
1da177e4	222	{
173d95bc	223	if (wdt_expect_close == 42)
1da177e4 LT	224	wdt_turnoff();
	225	else {
	226	/* wim: shouldn't there be a: del_timer(&timer); */
27c766aa	227	pr_crit("device file closed unexpectedly. Will not stop the WDT!\n");
1da177e4 LT	228	}
	229	clear_bit(0, &wdt_is_open);
	230	wdt_expect_close = 0;
	231	return 0;
	232	}
	233
173d95bc	234	static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1da177e4 LT	235	{
	236	void __user argp = (void __user )arg;
	237	int __user *p = argp;
42747d71	238	static const struct watchdog_info ident = {
173d95bc AC	239	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT
173d95bc AC	240	\| WDIOF_MAGICCLOSE,
1da177e4 LT	241	.firmware_version = 1,
	242	.identity = "ALiM7101",
	243	};
	244
173d95bc AC	245	switch (cmd) {
	246	case WDIOC_GETSUPPORT:
	247	return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
	248	case WDIOC_GETSTATUS:
	249	case WDIOC_GETBOOTSTATUS:
	250	return put_user(0, p);
173d95bc	251	case WDIOC_SETOPTIONS:
1da177e4	252	{
173d95bc	253	int new_options, retval = -EINVAL;
1da177e4	254
173d95bc AC	255	if (get_user(new_options, p))
	256	return -EFAULT;
	257	if (new_options & WDIOS_DISABLECARD) {
	258	wdt_turnoff();
	259	retval = 0;
1da177e4	260	}
173d95bc AC	261	if (new_options & WDIOS_ENABLECARD) {
	262	wdt_startup();
	263	retval = 0;
1da177e4	264	}
173d95bc AC	265	return retval;
173d95bc AC	266	}
0c06090c WVS	267	case WDIOC_KEEPALIVE:
	268	wdt_keepalive();
	269	return 0;
173d95bc AC	270	case WDIOC_SETTIMEOUT:
	271	{
	272	int new_timeout;
	273
	274	if (get_user(new_timeout, p))
	275	return -EFAULT;
	276	/* arbitrary upper limit */
	277	if (new_timeout < 1 \|\| new_timeout > 3600)
	278	return -EINVAL;
	279	timeout = new_timeout;
	280	wdt_keepalive();
	281	/* Fall through */
	282	}
	283	case WDIOC_GETTIMEOUT:
	284	return put_user(timeout, p);
	285	default:
	286	return -ENOTTY;
1da177e4 LT	287	}
	288	}
	289
62322d25	290	static const struct file_operations wdt_fops = {
173d95bc AC	291	.owner = THIS_MODULE,
	292	.llseek = no_llseek,
	293	.write = fop_write,
	294	.open = fop_open,
	295	.release = fop_close,
	296	.unlocked_ioctl = fop_ioctl,
1da177e4 LT	297	};
	298
	299	static struct miscdevice wdt_miscdev = {
173d95bc AC	300	.minor = WATCHDOG_MINOR,
	301	.name = "watchdog",
	302	.fops = &wdt_fops,
1da177e4 LT	303	};
	304
	305	/*
	306	* Notifier for system down
	307	*/
	308
173d95bc AC	309	static int wdt_notify_sys(struct notifier_block *this,
173d95bc AC	310	unsigned long code, void *unused)
1da177e4	311	{
173d95bc	312	if (code == SYS_DOWN \|\| code == SYS_HALT)
1da177e4 LT	313	wdt_turnoff();
1da177e4 LT	314
173d95bc	315	if (code == SYS_RESTART) {
1da177e4	316	/*
173d95bc AC	317	* Cobalt devices have no way of rebooting themselves other
	318	* than getting the watchdog to pull reset, so we restart the
	319	* watchdog on reboot with no heartbeat
1da177e4 LT	320	*/
1da177e4 LT	321	wdt_change(WDT_ENABLE);
27c766aa	322	pr_info("Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second\n");
1da177e4 LT	323	}
	324	return NOTIFY_DONE;
	325	}
	326
	327	/*
	328	* The WDT needs to learn about soft shutdowns in order to
	329	* turn the timebomb registers off.
	330	*/
	331
173d95bc	332	static struct notifier_block wdt_notifier = {
1da177e4 LT	333	.notifier_call = wdt_notify_sys,
	334	};
	335
	336	static void __exit alim7101_wdt_unload(void)
	337	{
	338	wdt_turnoff();
	339	/* Deregister */
	340	misc_deregister(&wdt_miscdev);
	341	unregister_reboot_notifier(&wdt_notifier);
02be2ee9	342	pci_dev_put(alim7101_pmu);
1da177e4 LT	343	}
	344
	345	static int __init alim7101_wdt_init(void)
	346	{
	347	int rc = -EBUSY;
	348	struct pci_dev *ali1543_south;
	349	char tmp;
	350
27c766aa	351	pr_info("Steve Hill <steve@navaho.co.uk>\n");
02be2ee9 JS	352	alim7101_pmu = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101,
02be2ee9 JS	353	NULL);
1da177e4	354	if (!alim7101_pmu) {
27c766aa	355	pr_info("ALi M7101 PMU not present - WDT not set\n");
1da177e4 LT	356	return -EBUSY;
	357	}
	358
	359	/* Set the WDT in the PMU to 1 second */
	360	pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, 0x02);
	361
02be2ee9 JS	362	ali1543_south = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533,
02be2ee9 JS	363	NULL);
1da177e4	364	if (!ali1543_south) {
27c766aa	365	pr_info("ALi 1543 South-Bridge not present - WDT not set\n");
02be2ee9	366	goto err_out;
1da177e4 LT	367	}
1da177e4 LT	368	pci_read_config_byte(ali1543_south, 0x5e, &tmp);
02be2ee9	369	pci_dev_put(ali1543_south);
1da177e4 LT	370	if ((tmp & 0x1e) == 0x00) {
1da177e4 LT	371	if (!use_gpio) {
27c766aa	372	pr_info("Detected old alim7101 revision 'a1d'. If this is a cobalt board, set the 'use_gpio' module parameter.\n");
02be2ee9	373	goto err_out;
173d95bc	374	}
1da177e4 LT	375	nowayout = 1;
1da177e4 LT	376	} else if ((tmp & 0x1e) != 0x12 && (tmp & 0x1e) != 0x00) {
27c766aa	377	pr_info("ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n");
02be2ee9	378	goto err_out;
1da177e4 LT	379	}
1da177e4 LT	380
173d95bc AC	381	if (timeout < 1 \|\| timeout > 3600) {
173d95bc AC	382	/* arbitrary upper limit */
1da177e4	383	timeout = WATCHDOG_TIMEOUT;
27c766aa JP	384	pr_info("timeout value must be 1 <= x <= 3600, using %d\n",
27c766aa JP	385	timeout);
1da177e4 LT	386	}
1da177e4 LT	387
c6cb13ae	388	rc = register_reboot_notifier(&wdt_notifier);
1da177e4	389	if (rc) {
27c766aa	390	pr_err("cannot register reboot notifier (err=%d)\n", rc);
1da177e4 LT	391	goto err_out;
	392	}
	393
c6cb13ae	394	rc = misc_register(&wdt_miscdev);
1da177e4	395	if (rc) {
27c766aa JP	396	pr_err("cannot register miscdev on minor=%d (err=%d)\n",
27c766aa JP	397	wdt_miscdev.minor, rc);
c6cb13ae	398	goto err_out_reboot;
1da177e4 LT	399	}
1da177e4 LT	400
173d95bc	401	if (nowayout)
1da177e4	402	__module_get(THIS_MODULE);
1da177e4	403
27c766aa	404	pr_info("WDT driver for ALi M7101 initialised. timeout=%d sec (nowayout=%d)\n",
1da177e4 LT	405	timeout, nowayout);
	406	return 0;
	407
c6cb13ae WVS	408	err_out_reboot:
c6cb13ae WVS	409	unregister_reboot_notifier(&wdt_notifier);
1da177e4	410	err_out:
02be2ee9	411	pci_dev_put(alim7101_pmu);
1da177e4 LT	412	return rc;
	413	}
	414
	415	module_init(alim7101_wdt_init);
	416	module_exit(alim7101_wdt_unload);
	417
4562f539	418	static DEFINE_PCI_DEVICE_TABLE(alim7101_pci_tbl) __used = {
29d73aab JS	419	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533) },
29d73aab JS	420	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
5cacb9f8 BC	421	{ }
	422	};
	423
	424	MODULE_DEVICE_TABLE(pci, alim7101_pci_tbl);
	425
1da177e4 LT	426	MODULE_AUTHOR("Steve Hill");
	427	MODULE_DESCRIPTION("ALi M7101 PMU Computer Watchdog Timer driver");
	428	MODULE_LICENSE("GPL");
	429	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);