static ssize_t iTCO_wdt_trigger_write(struct file *file, const char __user *buff,
		size_t count, loff_t *ppos)
{
	iTCO_wdt_last_kick(1);

	return 0;
}
static long iTCO_wdt_ioctl(struct file *file, unsigned int cmd,
							unsigned long arg)
{
	int new_options, retval = -EINVAL;
	int new_heartbeat;
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	static const struct watchdog_info ident = {
		.options =		WDIOF_SETTIMEOUT |
					WDIOF_KEEPALIVEPING |
					WDIOF_MAGICCLOSE,
		.firmware_version =	0,
		.identity =		DRV_NAME,
	};

	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:
	{
		if (get_user(new_options, p))
			return -EFAULT;

		if (new_options & WDIOS_DISABLECARD) {
			iTCO_wdt_stop();
			retval = 0;
		}
		if (new_options & WDIOS_ENABLECARD) {
			iTCO_wdt_keepalive();
			iTCO_wdt_start();
			retval = 0;
		}
		return retval;
	}
	case WDIOC_KEEPALIVE:
		iTCO_wdt_keepalive();
		return 0;

	case WDIOC_SETTIMEOUT:
	{
		if (get_user(new_heartbeat, p))
			return -EFAULT;
		if (iTCO_wdt_set_heartbeat(new_heartbeat))
			return -EINVAL;
		iTCO_wdt_keepalive();
		/* Fall */
	}
	case WDIOC_GETTIMEOUT:
		return put_user(heartbeat, p);
	case WDIOC_GETTIMELEFT:
	{
		int time_left;
		if (iTCO_wdt_get_timeleft(&time_left))
			return -EINVAL;
		return put_user(time_left, p);
	}
	default:
		return -ENOTTY;
	}
}

/*
 *	Kernel Interfaces
 */

static const struct file_operations iTCO_wdt_fops = {
	.owner =		THIS_MODULE,
	.llseek =		no_llseek,
	.write =		iTCO_wdt_write,
	.unlocked_ioctl =	iTCO_wdt_ioctl,
	.open =			iTCO_wdt_open,
	.release =		iTCO_wdt_release,
};

static struct miscdevice iTCO_wdt_miscdev = {
	.minor =	WATCHDOG_MINOR,
	.name =		"watchdog",
	.fops =		&iTCO_wdt_fops,
};

/*
 *	Reboot notifier
 */

static int TCO_reboot_notifier(struct notifier_block *this,
			   unsigned long code,
			   void *another_unused)
{
	if (code == SYS_HALT || code == SYS_POWER_OFF) {
		iTCO_wdt_set_reset_type(TCO_POLICY_HALT);
	}

	iTCO_wdt_last_kick(5);

#ifdef CONFIG_DEBUG_FS
	if (iTCO_wdt_private.panic_reboot_notifier) {
		BUG();
	}
#endif

	return NOTIFY_DONE;
}

static irqreturn_t tco_irq_handler(int irq, void *arg)
{
	pr_warn("[SHTDWN] %s, WATCHDOG TIMEOUT HANDLER!\n", __func__);

	/* reduce the timeout to the minimum, but sufficient for tracing */
	bypass_keepalive = false;
	iTCO_wdt_last_kick(15);

	trigger_all_cpu_backtrace();

	/* Let the watchdog reset the board */
	panic_timeout = 0;
	panic("Kernel Watchdog");

	/* This code should not be reached */

	return IRQ_HANDLED;
}


static ssize_t shutdown_ongoing_store(struct device *dev,
			struct device_attribute *attr, const char *buf, size_t size)
{
	iTCO_wdt_set_reset_type(TCO_POLICY_HALT);
	return size;
}
static long iTCO_wdt_ioctl(struct file *file, unsigned int cmd,
							unsigned long arg)
{
	int new_options, retval = -EINVAL;
	int new_heartbeat;
	void __user *argp = (void __user *)arg;
	int __user *p = argp;
	static const struct watchdog_info ident = {
		.options =		WDIOF_SETTIMEOUT |
					WDIOF_KEEPALIVEPING |
					WDIOF_MAGICCLOSE,
		.firmware_version =	0,
		.identity =		DRV_NAME,
	};

	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:
	{
		if (get_user(new_options, p))
			return -EFAULT;

		if (new_options & WDIOS_DISABLECARD) {
			iTCO_wdt_stop();
			retval = 0;
		}
		if (new_options & WDIOS_ENABLECARD) {
			iTCO_wdt_keepalive();
			iTCO_wdt_start();
			retval = 0;
		}
		return retval;
	}
	case WDIOC_KEEPALIVE:
		iTCO_wdt_keepalive();
		return 0;

	case WDIOC_SETTIMEOUT:
	{
		if (get_user(new_heartbeat, p))
			return -EFAULT;
		if (iTCO_wdt_set_heartbeat(new_heartbeat))
			return -EINVAL;
		iTCO_wdt_keepalive();
		/* Fall */
	}
	case WDIOC_GETTIMEOUT:
		return put_user(heartbeat, p);
	case WDIOC_GETTIMELEFT:
	{
		int time_left;
		if (iTCO_wdt_get_timeleft(&time_left))
			return -EINVAL;
		return put_user(time_left, p);
	}
	default:
		return -ENOTTY;
	}
}

/*
 *	Kernel Interfaces
 */

static const struct file_operations iTCO_wdt_fops = {
	.owner =		THIS_MODULE,
	.llseek =		no_llseek,
	.write =		iTCO_wdt_write,
	.unlocked_ioctl =	iTCO_wdt_ioctl,
	.open =			iTCO_wdt_open,
	.release =		iTCO_wdt_release,
};

static struct miscdevice iTCO_wdt_miscdev = {
	.minor =	WATCHDOG_MINOR,
	.name =		"watchdog",
	.fops =		&iTCO_wdt_fops,
};

/*
 *	Reboot notifier
 */

static int TCO_reboot_notifier(struct notifier_block *this,
			   unsigned long code,
			   void *another_unused)
{
	if (code == SYS_HALT || code == SYS_POWER_OFF) {
		iTCO_wdt_set_reset_type(TCO_POLICY_HALT);
	}

	iTCO_wdt_last_kick(5);

#ifdef CONFIG_DEBUG_FS
	if (iTCO_wdt_private.panic_reboot_notifier) {
		BUG();
	}
#endif

	return NOTIFY_DONE;
}

static irqreturn_t tco_irq_handler(int irq, void *arg)
{
	unsigned long val32;

	pr_warn("[SHTDWN] %s, WATCHDOG TIMEOUT HANDLER!\n", __func__);

	/* reduce the timeout to the minimum, but sufficient for tracing */
	iTCO_wdt_set_heartbeat(15);
	iTCO_wdt_keepalive();

	trigger_all_cpu_backtrace();
	panic("Kernel Watchdog");

	/* This code should not be reached */

	return IRQ_HANDLED;
}

/*
 *	Init & exit routines
 */

static int iTCO_wdt_init(struct pci_dev *pdev,
		const struct pci_device_id *ent, struct platform_device *dev)
{
	int ret;
	u32 base_address;
	unsigned long val32;

	/*
	 *      Find the ACPI/PM base I/O address which is the base
	 *      for the TCO registers (TCOBASE=ACPIBASE + 0x60)
	 *      ACPIBASE is bits [15:7] from 0x40-0x43
	 */
	pci_read_config_dword(pdev, 0x40, &base_address);
	base_address &= 0x0000ff80;
	if (base_address == 0x00000000) {
		/* Something's wrong here, ACPIBASE has to be set */
		pr_err("failed to get TCOBASE address, device disabled by hardware/BIOS\n");
		return -ENODEV;
	}
	iTCO_wdt_private.iTCO_version =
			iTCO_chipset_info[ent->driver_data].iTCO_version;
	iTCO_wdt_private.ACPIBASE = base_address;
	iTCO_wdt_private.pdev = pdev;

	pci_read_config_dword(pdev, 0x44, &pmc_base_address);
	pmc_base_address &= 0xFFFFFE00;

	/*
	 * Disable watchdog on command-line demand
	 */
	if (strstr(saved_command_line, "disable_kernel_watchdog=1")) {
		pr_warn("disable_kernel_watchdog=1 watchdog will not be started\n");
		iTCO_wdt_private.enable = false;
		/* Set the NO_REBOOT bit to prevent later reboots */
		iTCO_wdt_set_NO_REBOOT_bit();
		/* Ensure Wdt is well stopped in case started by IAFW */
		iTCO_wdt_stop();
	} else {
		iTCO_wdt_private.enable = true;
		/* Check chipset's NO_REBOOT bit */
		if (iTCO_wdt_unset_NO_REBOOT_bit()) {
			pr_err("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
			ret = -ENODEV;	/* Cannot reset NO_REBOOT bit */
			goto out;
		}
	}

	/* The TCO logic uses the TCO_EN bit in the SMI_EN register */
	if (!request_region(SMI_EN, 4, "iTCO_wdt")) {
		pr_err("I/O address 0x%04lx already in use, device disabled\n",
		       SMI_EN);
		ret = -EIO;
		goto out;
	}
	if (!request_region(SMI_STS, 4,	"iTCO_wdt")) {
		pr_err("I/O address 0x%04lx already in use, device disabled\n",
				SMI_STS);
		ret = -EIO;
		goto unreg_smi_sts;
	}

	if (turn_SMI_watchdog_clear_off >= iTCO_wdt_private.iTCO_version) {
		/* Bit 13: TCO_EN -> 0 = Disables TCO logic generating an SMI# */
		val32 = inl(SMI_EN);
		val32 &= ~TCO_EN_BIT;	/* Turn off TCO watchdog timer */
		outl(val32, SMI_EN);
	}

	/* The TCO I/O registers reside in a 32-byte range pointed to
	   by the TCOBASE value */
	if (!request_region(TCOBASE, 0x20, "iTCO_wdt")) {
		pr_err("I/O address 0x%04lx already in use, device disabled\n",
		       TCOBASE);
		ret = -EIO;
		goto unreg_smi_en;
	}

	pr_info("Found a %s TCO device (Version=%d, TCOBASE=0x%04lx)\n",
		iTCO_chipset_info[ent->driver_data].name,
		iTCO_chipset_info[ent->driver_data].iTCO_version,
		TCOBASE);

	/* Check that the heartbeat value is within it's range;
	   if not reset to the default */
	if (iTCO_wdt_set_heartbeat(heartbeat)) {
		iTCO_wdt_set_heartbeat(WATCHDOG_HEARTBEAT);
		pr_info("timeout value out of range, using %d\n", heartbeat);
	}

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

	pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
		heartbeat, nowayout);

	/* Reset OS policy */
	iTCO_wdt_set_reset_type(TCO_POLICY_NORM);

	ret = acpi_register_gsi(NULL, TCO_WARNING_IRQ,
				ACPI_EDGE_SENSITIVE, ACPI_ACTIVE_HIGH);
	if (ret < 0) {
		pr_err("failed to configure TCO warning IRQ %d\n", TCO_WARNING_IRQ);
		goto misc_unreg;
	}
	ret = request_irq(TCO_WARNING_IRQ, tco_irq_handler, 0, "tco_watchdog", NULL);
	if (ret < 0) {
		pr_err("failed to request TCO warning IRQ %d\n", TCO_WARNING_IRQ);
		goto gsi_unreg;
	}

	/* Clear old TCO timeout status */
	val32 = TCO_TIMEOUT_BIT | SECOND_TO_STS_BIT;
	outl(val32, TCO1_STS);
	/* Clear the SMI status */
	outl(TCO_STS_BIT, SMI_STS);

	/* Enable SMI for TCO */
	val32 = inl(SMI_EN);
	val32 |= TCO_EN_BIT;
	outl(val32, SMI_EN);
	/* then ensure that PMC is ready to handle next SMI */
	val32 |= EOS_BIT;
	outl(val32, SMI_EN);

	reboot_notifier.notifier_call = TCO_reboot_notifier;
	reboot_notifier.priority = 1;
	ret = register_reboot_notifier(&reboot_notifier);
	if (ret)
		/* We continue as reboot notifier is not critical for
			 * watchdog */
		pr_err("cannot register reboot notifier %d\n", ret);

	return 0;

gsi_unreg:
	acpi_unregister_gsi(TCO_WARNING_IRQ);
misc_unreg:
	misc_deregister(&iTCO_wdt_miscdev);
unreg_region:
	release_region(TCOBASE, 0x20);
unreg_smi_sts:
	release_region(SMI_STS, 4);
unreg_smi_en:
	release_region(SMI_EN, 4);
out:
	iTCO_wdt_private.ACPIBASE = 0;
	return ret;
}