[mirror_ubuntu-bionic-kernel.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>
 */

#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 OUR_NAME "alim7101_wdt"
#define PFX OUR_NAME ": "

#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 int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 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 {
		printk(KERN_WARNING PFX
			"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);

	printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
}

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

			/* 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); */
		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 long fop_ioctl(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 = "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_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;
		/* 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);
		printk(KERN_INFO PFX "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;

	printk(KERN_INFO PFX "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) {
		printk(KERN_INFO PFX "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) {
		printk(KERN_INFO PFX
			"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) {
			printk(KERN_INFO PFX "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) {
		printk(KERN_INFO PFX "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;
		printk(KERN_INFO PFX
			"timeout value must be 1 <= x <= 3600, using %d\n",
								timeout);
	}

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

	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_reboot;
	}

	if (nowayout)
		__module_get(THIS_MODULE);

	printk(KERN_INFO PFX "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 struct pci_device_id alim7101_pci_tbl[] __devinitdata = {
	{ 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
	22	#include <linux/module.h>
	23	#include <linux/moduleparam.h>
	24	#include <linux/types.h>
	25	#include <linux/timer.h>
	26	#include <linux/miscdevice.h>
	27	#include <linux/watchdog.h>
	28	#include <linux/ioport.h>
	29	#include <linux/notifier.h>
	30	#include <linux/reboot.h>
	31	#include <linux/init.h>
	32	#include <linux/fs.h>
	33	#include <linux/pci.h>
	34
173d95bc AC	35	#include <linux/io.h>
173d95bc AC	36	#include <linux/uaccess.h>
1da177e4 LT	37	#include <asm/system.h>
	38
	39	#define OUR_NAME "alim7101_wdt"
	40	#define PFX OUR_NAME ": "
	41
	42	#define WDT_ENABLE 0x9C
	43	#define WDT_DISABLE 0x8C
	44
	45	#define ALI_7101_WDT 0x92
	46	#define ALI_7101_GPIO 0x7D
	47	#define ALI_7101_GPIO_O 0x7E
	48	#define ALI_WDT_ARM 0x01
	49
	50	/*
	51	* We're going to use a 1 second timeout.
	52	* If we reset the watchdog every ~250ms we should be safe. */
	53
	54	#define WDT_INTERVAL (HZ/4+1)
	55
	56	/*
	57	* We must not require too good response from the userspace daemon.
	58	* Here we require the userspace daemon to send us a heartbeat
	59	* char to /dev/watchdog every 30 seconds.
	60	*/
	61
	62	#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */
173d95bc AC	63	/* in seconds, will be multiplied by HZ to get seconds to wait for a ping */
173d95bc AC	64	static int timeout = WATCHDOG_TIMEOUT;
1da177e4	65	module_param(timeout, int, 0);
173d95bc AC	66	MODULE_PARM_DESC(timeout,
	67	"Watchdog timeout in seconds. (1<=timeout<=3600, default="
	68	__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
1da177e4	69
173d95bc	70	static int use_gpio; /* Use the pic (for a1d revision alim7101) */
1da177e4	71	module_param(use_gpio, int, 0);
173d95bc AC	72	MODULE_PARM_DESC(use_gpio,
173d95bc AC	73	"Use the gpio watchdog (required by old cobalt boards).");
1da177e4 LT	74
1da177e4 LT	75	static void wdt_timer_ping(unsigned long);
82eb7c50	76	static DEFINE_TIMER(timer, wdt_timer_ping, 0, 1);
1da177e4 LT	77	static unsigned long next_heartbeat;
	78	static unsigned long wdt_is_open;
	79	static char wdt_expect_close;
	80	static struct pci_dev *alim7101_pmu;
	81
4bfdf378	82	static int nowayout = WATCHDOG_NOWAYOUT;
1da177e4	83	module_param(nowayout, int, 0);
173d95bc AC	84	MODULE_PARM_DESC(nowayout,
	85	"Watchdog cannot be stopped once started (default="
	86	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
1da177e4 LT	87
	88	/*
	89	* Whack the dog
	90	*/
	91
	92	static void wdt_timer_ping(unsigned long data)
	93	{
	94	/* If we got a heartbeat pulse within the WDT_US_INTERVAL
	95	* we agree to ping the WDT
	96	*/
173d95bc	97	char tmp;
1da177e4	98
173d95bc	99	if (time_before(jiffies, next_heartbeat)) {
1da177e4 LT	100	/* Ping the WDT (this is actually a disarm/arm sequence) */
1da177e4 LT	101	pci_read_config_byte(alim7101_pmu, 0x92, &tmp);
173d95bc AC	102	pci_write_config_byte(alim7101_pmu,
	103	ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
	104	pci_write_config_byte(alim7101_pmu,
	105	ALI_7101_WDT, (tmp \| ALI_WDT_ARM));
1da177e4	106	if (use_gpio) {
173d95bc AC	107	pci_read_config_byte(alim7101_pmu,
	108	ALI_7101_GPIO_O, &tmp);
	109	pci_write_config_byte(alim7101_pmu,
	110	ALI_7101_GPIO_O, tmp \| 0x20);
	111	pci_write_config_byte(alim7101_pmu,
	112	ALI_7101_GPIO_O, tmp & ~0x20);
1da177e4 LT	113	}
1da177e4 LT	114	} else {
173d95bc AC	115	printk(KERN_WARNING PFX
173d95bc AC	116	"Heartbeat lost! Will not ping the watchdog\n");
1da177e4 LT	117	}
1da177e4 LT	118	/* Re-set the timer interval */
82eb7c50	119	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4 LT	120	}
	121
	122	/*
	123	* Utility routines
	124	*/
	125
	126	static void wdt_change(int writeval)
	127	{
	128	char tmp;
	129
	130	pci_read_config_byte(alim7101_pmu, ALI_7101_WDT, &tmp);
	131	if (writeval == WDT_ENABLE) {
173d95bc AC	132	pci_write_config_byte(alim7101_pmu,
173d95bc AC	133	ALI_7101_WDT, (tmp \| ALI_WDT_ARM));
1da177e4	134	if (use_gpio) {
173d95bc AC	135	pci_read_config_byte(alim7101_pmu,
	136	ALI_7101_GPIO_O, &tmp);
	137	pci_write_config_byte(alim7101_pmu,
	138	ALI_7101_GPIO_O, tmp & ~0x20);
1da177e4 LT	139	}
	140
	141	} else {
173d95bc AC	142	pci_write_config_byte(alim7101_pmu,
173d95bc AC	143	ALI_7101_WDT, (tmp & ~ALI_WDT_ARM));
1da177e4	144	if (use_gpio) {
173d95bc AC	145	pci_read_config_byte(alim7101_pmu,
	146	ALI_7101_GPIO_O, &tmp);
	147	pci_write_config_byte(alim7101_pmu,
	148	ALI_7101_GPIO_O, tmp \| 0x20);
1da177e4 LT	149	}
	150	}
	151	}
	152
	153	static void wdt_startup(void)
	154	{
	155	next_heartbeat = jiffies + (timeout * HZ);
	156
	157	/* We must enable before we kick off the timer in case the timer
	158	occurs as we ping it */
	159
	160	wdt_change(WDT_ENABLE);
	161
	162	/* Start the timer */
82eb7c50	163	mod_timer(&timer, jiffies + WDT_INTERVAL);
1da177e4 LT	164
	165	printk(KERN_INFO PFX "Watchdog timer is now enabled.\n");
	166	}
	167
	168	static void wdt_turnoff(void)
	169	{
	170	/* Stop the timer */
	171	del_timer_sync(&timer);
	172	wdt_change(WDT_DISABLE);
	173	printk(KERN_INFO PFX "Watchdog timer is now disabled...\n");
	174	}
	175
	176	static void wdt_keepalive(void)
	177	{
	178	/* user land ping */
	179	next_heartbeat = jiffies + (timeout * HZ);
	180	}
	181
	182	/*
	183	* /dev/watchdog handling
	184	*/
	185
173d95bc AC	186	static ssize_t fop_write(struct file file, const char __user buf,
173d95bc AC	187	size_t count, loff_t *ppos)
1da177e4 LT	188	{
1da177e4 LT	189	/* See if we got the magic character 'V' and reload the timer */
173d95bc	190	if (count) {
1da177e4 LT	191	if (!nowayout) {
	192	size_t ofs;
	193
	194	/* note: just in case someone wrote the magic character
	195	* five months ago... */
	196	wdt_expect_close = 0;
	197
	198	/* now scan */
	199	for (ofs = 0; ofs != count; ofs++) {
	200	char c;
	201	if (get_user(c, buf+ofs))
	202	return -EFAULT;
	203	if (c == 'V')
	204	wdt_expect_close = 42;
	205	}
	206	}
	207	/* someone wrote to us, we should restart timer */
	208	wdt_keepalive();
	209	}
	210	return count;
	211	}
	212
173d95bc	213	static int fop_open(struct inode inode, struct file file)
1da177e4 LT	214	{
1da177e4 LT	215	/* Just in case we're already talking to someone... */
173d95bc	216	if (test_and_set_bit(0, &wdt_is_open))
1da177e4 LT	217	return -EBUSY;
	218	/* Good, fire up the show */
	219	wdt_startup();
	220	return nonseekable_open(inode, file);
	221	}
	222
173d95bc	223	static int fop_close(struct inode inode, struct file file)
1da177e4	224	{
173d95bc	225	if (wdt_expect_close == 42)
1da177e4 LT	226	wdt_turnoff();
	227	else {
	228	/* wim: shouldn't there be a: del_timer(&timer); */
173d95bc AC	229	printk(KERN_CRIT PFX
173d95bc AC	230	"device file closed unexpectedly. Will not stop the WDT!\n");
1da177e4 LT	231	}
	232	clear_bit(0, &wdt_is_open);
	233	wdt_expect_close = 0;
	234	return 0;
	235	}
	236
173d95bc	237	static long fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1da177e4 LT	238	{
	239	void __user argp = (void __user )arg;
	240	int __user *p = argp;
173d95bc AC	241	static struct watchdog_info ident = {
	242	.options = WDIOF_KEEPALIVEPING \| WDIOF_SETTIMEOUT
	243	\| WDIOF_MAGICCLOSE,
1da177e4 LT	244	.firmware_version = 1,
	245	.identity = "ALiM7101",
	246	};
	247
173d95bc AC	248	switch (cmd) {
	249	case WDIOC_GETSUPPORT:
	250	return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
	251	case WDIOC_GETSTATUS:
	252	case WDIOC_GETBOOTSTATUS:
	253	return put_user(0, p);
	254	case WDIOC_KEEPALIVE:
	255	wdt_keepalive();
	256	return 0;
	257	case WDIOC_SETOPTIONS:
1da177e4	258	{
173d95bc	259	int new_options, retval = -EINVAL;
1da177e4	260
173d95bc AC	261	if (get_user(new_options, p))
	262	return -EFAULT;
	263	if (new_options & WDIOS_DISABLECARD) {
	264	wdt_turnoff();
	265	retval = 0;
1da177e4	266	}
173d95bc AC	267	if (new_options & WDIOS_ENABLECARD) {
	268	wdt_startup();
	269	retval = 0;
1da177e4	270	}
173d95bc AC	271	return retval;
	272	}
	273	case WDIOC_SETTIMEOUT:
	274	{
	275	int new_timeout;
	276
	277	if (get_user(new_timeout, p))
	278	return -EFAULT;
	279	/* arbitrary upper limit */
	280	if (new_timeout < 1 \|\| new_timeout > 3600)
	281	return -EINVAL;
	282	timeout = new_timeout;
	283	wdt_keepalive();
	284	/* Fall through */
	285	}
	286	case WDIOC_GETTIMEOUT:
	287	return put_user(timeout, p);
	288	default:
	289	return -ENOTTY;
1da177e4 LT	290	}
	291	}
	292
62322d25	293	static const struct file_operations wdt_fops = {
173d95bc AC	294	.owner = THIS_MODULE,
	295	.llseek = no_llseek,
	296	.write = fop_write,
	297	.open = fop_open,
	298	.release = fop_close,
	299	.unlocked_ioctl = fop_ioctl,
1da177e4 LT	300	};
	301
	302	static struct miscdevice wdt_miscdev = {
173d95bc AC	303	.minor = WATCHDOG_MINOR,
	304	.name = "watchdog",
	305	.fops = &wdt_fops,
1da177e4 LT	306	};
	307
	308	/*
	309	* Notifier for system down
	310	*/
	311
173d95bc AC	312	static int wdt_notify_sys(struct notifier_block *this,
173d95bc AC	313	unsigned long code, void *unused)
1da177e4	314	{
173d95bc	315	if (code == SYS_DOWN \|\| code == SYS_HALT)
1da177e4 LT	316	wdt_turnoff();
1da177e4 LT	317
173d95bc	318	if (code == SYS_RESTART) {
1da177e4	319	/*
173d95bc AC	320	* Cobalt devices have no way of rebooting themselves other
	321	* than getting the watchdog to pull reset, so we restart the
	322	* watchdog on reboot with no heartbeat
1da177e4 LT	323	*/
	324	wdt_change(WDT_ENABLE);
	325	printk(KERN_INFO PFX "Watchdog timer is now enabled with no heartbeat - should reboot in ~1 second.\n");
	326	}
	327	return NOTIFY_DONE;
	328	}
	329
	330	/*
	331	* The WDT needs to learn about soft shutdowns in order to
	332	* turn the timebomb registers off.
	333	*/
	334
173d95bc	335	static struct notifier_block wdt_notifier = {
1da177e4 LT	336	.notifier_call = wdt_notify_sys,
	337	};
	338
	339	static void __exit alim7101_wdt_unload(void)
	340	{
	341	wdt_turnoff();
	342	/* Deregister */
	343	misc_deregister(&wdt_miscdev);
	344	unregister_reboot_notifier(&wdt_notifier);
02be2ee9	345	pci_dev_put(alim7101_pmu);
1da177e4 LT	346	}
	347
	348	static int __init alim7101_wdt_init(void)
	349	{
	350	int rc = -EBUSY;
	351	struct pci_dev *ali1543_south;
	352	char tmp;
	353
	354	printk(KERN_INFO PFX "Steve Hill <steve@navaho.co.uk>.\n");
02be2ee9 JS	355	alim7101_pmu = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101,
02be2ee9 JS	356	NULL);
1da177e4 LT	357	if (!alim7101_pmu) {
	358	printk(KERN_INFO PFX "ALi M7101 PMU not present - WDT not set\n");
	359	return -EBUSY;
	360	}
	361
	362	/* Set the WDT in the PMU to 1 second */
	363	pci_write_config_byte(alim7101_pmu, ALI_7101_WDT, 0x02);
	364
02be2ee9 JS	365	ali1543_south = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533,
02be2ee9 JS	366	NULL);
1da177e4	367	if (!ali1543_south) {
173d95bc AC	368	printk(KERN_INFO PFX
173d95bc AC	369	"ALi 1543 South-Bridge not present - WDT not set\n");
02be2ee9	370	goto err_out;
1da177e4 LT	371	}
1da177e4 LT	372	pci_read_config_byte(ali1543_south, 0x5e, &tmp);
02be2ee9	373	pci_dev_put(ali1543_south);
1da177e4 LT	374	if ((tmp & 0x1e) == 0x00) {
	375	if (!use_gpio) {
	376	printk(KERN_INFO PFX "Detected old alim7101 revision 'a1d'. If this is a cobalt board, set the 'use_gpio' module parameter.\n");
02be2ee9	377	goto err_out;
173d95bc	378	}
1da177e4 LT	379	nowayout = 1;
	380	} else if ((tmp & 0x1e) != 0x12 && (tmp & 0x1e) != 0x00) {
	381	printk(KERN_INFO PFX "ALi 1543 South-Bridge does not have the correct revision number (???1001?) - WDT not set\n");
02be2ee9	382	goto err_out;
1da177e4 LT	383	}
1da177e4 LT	384
173d95bc AC	385	if (timeout < 1 \|\| timeout > 3600) {
173d95bc AC	386	/* arbitrary upper limit */
1da177e4	387	timeout = WATCHDOG_TIMEOUT;
173d95bc AC	388	printk(KERN_INFO PFX
	389	"timeout value must be 1 <= x <= 3600, using %d\n",
	390	timeout);
1da177e4 LT	391	}
1da177e4 LT	392
c6cb13ae	393	rc = register_reboot_notifier(&wdt_notifier);
1da177e4	394	if (rc) {
173d95bc AC	395	printk(KERN_ERR PFX
173d95bc AC	396	"cannot register reboot notifier (err=%d)\n", rc);
1da177e4 LT	397	goto err_out;
	398	}
	399
c6cb13ae	400	rc = misc_register(&wdt_miscdev);
1da177e4	401	if (rc) {
c6cb13ae WVS	402	printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
	403	wdt_miscdev.minor, rc);
	404	goto err_out_reboot;
1da177e4 LT	405	}
1da177e4 LT	406
173d95bc	407	if (nowayout)
1da177e4	408	__module_get(THIS_MODULE);
1da177e4 LT	409
	410	printk(KERN_INFO PFX "WDT driver for ALi M7101 initialised. timeout=%d sec (nowayout=%d)\n",
	411	timeout, nowayout);
	412	return 0;
	413
c6cb13ae WVS	414	err_out_reboot:
c6cb13ae WVS	415	unregister_reboot_notifier(&wdt_notifier);
1da177e4	416	err_out:
02be2ee9	417	pci_dev_put(alim7101_pmu);
1da177e4 LT	418	return rc;
	419	}
	420
	421	module_init(alim7101_wdt_init);
	422	module_exit(alim7101_wdt_unload);
	423
5cacb9f8	424	static struct pci_device_id alim7101_pci_tbl[] __devinitdata = {
29d73aab JS	425	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533) },
29d73aab JS	426	{ PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
5cacb9f8 BC	427	{ }
	428	};
	429
	430	MODULE_DEVICE_TABLE(pci, alim7101_pci_tbl);
	431
1da177e4 LT	432	MODULE_AUTHOR("Steve Hill");
	433	MODULE_DESCRIPTION("ALi M7101 PMU Computer Watchdog Timer driver");
	434	MODULE_LICENSE("GPL");
	435	MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);