wdt_pci.c

linux-2.6.15.6

#ifdef CONFIG_WDT_501_PCI
	ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER);
	if (tachometer)
		ident.options |= WDIOF_FANFAULT;
#endif /* CONFIG_WDT_501_PCI */

	switch(cmd)
	{
		default:
			return -ENOIOCTLCMD;
		case WDIOC_GETSUPPORT:
			return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0;

		case WDIOC_GETSTATUS:
			wdtpci_get_status(&status);
			return put_user(status, p);
		case WDIOC_GETBOOTSTATUS:
			return put_user(0, p);
		case WDIOC_KEEPALIVE:
			wdtpci_ping();
			return 0;
		case WDIOC_SETTIMEOUT:
			if (get_user(new_heartbeat, p))
				return -EFAULT;

			if (wdtpci_set_heartbeat(new_heartbeat))
				return -EINVAL;

			wdtpci_ping();
			/* Fall */
		case WDIOC_GETTIMEOUT:
			return put_user(heartbeat, p);
	}
}

/**
 *	wdtpci_open:
 *	@inode: inode of device
 *	@file: file handle to device
 *
 *	The watchdog device has been opened. The watchdog device is single
 *	open and on opening we load the counters. Counter zero is a 100Hz
 *	cascade, into counter 1 which downcounts to reboot. When the counter
 *	triggers counter 2 downcounts the length of the reset pulse which
 *	set set to be as long as possible.
 */

static int wdtpci_open(struct inode *inode, struct file *file)
{
	if (down_trylock(&open_sem))
		return -EBUSY;

	if (nowayout) {
		__module_get(THIS_MODULE);
	}
	/*
	 *	Activate
	 */
	wdtpci_start();
	return nonseekable_open(inode, file);
}

/**
 *	wdtpci_release:
 *	@inode: inode to board
 *	@file: file handle to board
 *
 *	The watchdog has a configurable API. There is a religious dispute
 *	between people who want their watchdog to be able to shut down and
 *	those who want to be sure if the watchdog manager dies the machine
 *	reboots. In the former case we disable the counters, in the latter
 *	case you have to open it again very soon.
 */

static int wdtpci_release(struct inode *inode, struct file *file)
{
	if (expect_close == 42) {
		wdtpci_stop();
	} else {
		printk(KERN_CRIT PFX "Unexpected close, not stopping timer!");
		wdtpci_ping();
	}
	expect_close = 0;
	up(&open_sem);
	return 0;
}

#ifdef CONFIG_WDT_501_PCI
/**
 *	wdtpci_temp_read:
 *	@file: file handle to the watchdog board
 *	@buf: buffer to write 1 byte into
 *	@count: length of buffer
 *	@ptr: offset (no seek allowed)
 *
 *	Read reports the temperature in degrees Fahrenheit. The API is in
 *	fahrenheit. It was designed by an imperial measurement luddite.
 */

static ssize_t wdtpci_temp_read(struct file *file, char __user *buf, size_t count, loff_t *ptr)
{
	int temperature;

	if (wdtpci_get_temperature(&temperature))
		return -EFAULT;

	if (copy_to_user (buf, &temperature, 1))
		return -EFAULT;

	return 1;
}

/**
 *	wdtpci_temp_open:
 *	@inode: inode of device
 *	@file: file handle to device
 *
 *	The temperature device has been opened.
 */

static int wdtpci_temp_open(struct inode *inode, struct file *file)
{
	return nonseekable_open(inode, file);
}

/**
 *	wdtpci_temp_release:
 *	@inode: inode to board
 *	@file: file handle to board
 *
 *	The temperature device has been closed.
 */

static int wdtpci_temp_release(struct inode *inode, struct file *file)
{
	return 0;
}
#endif /* CONFIG_WDT_501_PCI */

/**
 *	notify_sys:
 *	@this: our notifier block
 *	@code: the event being reported
 *	@unused: unused
 *
 *	Our notifier is called on system shutdowns. We want to turn the card
 *	off at reboot otherwise the machine will reboot again during memory
 *	test or worse yet during the following fsck. This would suck, in fact
 *	trust me - if it happens it does suck.
 */

static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
	void *unused)
{
	if (code==SYS_DOWN || code==SYS_HALT) {
		/* Turn the card off */
		wdtpci_stop();
	}
	return NOTIFY_DONE;
}

/*
 *	Kernel Interfaces
 */


static struct file_operations wdtpci_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.write		= wdtpci_write,
	.ioctl		= wdtpci_ioctl,
	.open		= wdtpci_open,
	.release	= wdtpci_release,
};

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

#ifdef CONFIG_WDT_501_PCI
static struct file_operations wdtpci_temp_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.read		= wdtpci_temp_read,
	.open		= wdtpci_temp_open,
	.release	= wdtpci_temp_release,
};

static struct miscdevice temp_miscdev = {
	.minor	= TEMP_MINOR,
	.name	= "temperature",
	.fops	= &wdtpci_temp_fops,
};
#endif /* CONFIG_WDT_501_PCI */

/*
 *	The WDT card needs to learn about soft shutdowns in order to
 *	turn the timebomb registers off.
 */

static struct notifier_block wdtpci_notifier = {
	.notifier_call = wdtpci_notify_sys,
};


static int __devinit wdtpci_init_one (struct pci_dev *dev,
				   const struct pci_device_id *ent)
{
	int ret = -EIO;

	dev_count++;
	if (dev_count > 1) {
		printk (KERN_ERR PFX "this driver only supports 1 device\n");
		return -ENODEV;
	}

	if (pci_enable_device (dev)) {
		printk (KERN_ERR PFX "Not possible to enable PCI Device\n");
		return -ENODEV;
	}

	if (pci_resource_start (dev, 2) == 0x0000) {
		printk (KERN_ERR PFX "No I/O-Address for card detected\n");
		ret = -ENODEV;
		goto out_pci;
	}

	sema_init(&open_sem, 1);
	spin_lock_init(&wdtpci_lock);

	irq = dev->irq;
	io = pci_resource_start (dev, 2);

	if (request_region (io, 16, "wdt_pci") == NULL) {
		printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", io);
		goto out_pci;
	}

	if (request_irq (irq, wdtpci_interrupt, SA_INTERRUPT | SA_SHIRQ,
			 "wdt_pci", &wdtpci_miscdev)) {
		printk (KERN_ERR PFX "IRQ %d is not free\n", irq);
		goto out_reg;
	}

	printk ("PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%04x (Interrupt %d)\n",
		io, irq);

	/* Check that the heartbeat value is within it's range ; if not reset to the default */
	if (wdtpci_set_heartbeat(heartbeat)) {
		wdtpci_set_heartbeat(WD_TIMO);
		printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
			WD_TIMO);
	}

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

#ifdef CONFIG_WDT_501_PCI
	ret = misc_register (&temp_miscdev);
	if (ret) {
		printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
			TEMP_MINOR, ret);
		goto out_rbt;
	}
#endif /* CONFIG_WDT_501_PCI */

	ret = misc_register (&wdtpci_miscdev);
	if (ret) {
		printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
			WATCHDOG_MINOR, ret);
		goto out_misc;
	}

	printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
		heartbeat, nowayout);
#ifdef CONFIG_WDT_501_PCI
	printk(KERN_INFO "wdt: Fan Tachometer is %s\n", (tachometer ? "Enabled" : "Disabled"));
#endif /* CONFIG_WDT_501_PCI */

	ret = 0;
out:
	return ret;

out_misc:
#ifdef CONFIG_WDT_501_PCI
	misc_deregister(&temp_miscdev);
out_rbt:
#endif /* CONFIG_WDT_501_PCI */
	unregister_reboot_notifier(&wdtpci_notifier);
out_irq:
	free_irq(irq, &wdtpci_miscdev);
out_reg:
	release_region (io, 16);
out_pci:
	pci_disable_device(dev);
	goto out;
}


static void __devexit wdtpci_remove_one (struct pci_dev *pdev)
{
	/* here we assume only one device will ever have
	 * been picked up and registered by probe function */
	misc_deregister(&wdtpci_miscdev);
#ifdef CONFIG_WDT_501_PCI
	misc_deregister(&temp_miscdev);
#endif /* CONFIG_WDT_501_PCI */
	unregister_reboot_notifier(&wdtpci_notifier);
	free_irq(irq, &wdtpci_miscdev);
	release_region(io, 16);
	pci_disable_device(pdev);
	dev_count--;
}


static struct pci_device_id wdtpci_pci_tbl[] = {
	{
		.vendor	   = PCI_VENDOR_ID_ACCESSIO,
		.device	   = PCI_DEVICE_ID_WDG_CSM,
		.subvendor = PCI_ANY_ID,
		.subdevice = PCI_ANY_ID,
	},
	{ 0, }, /* terminate list */
};
MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);


static struct pci_driver wdtpci_driver = {
	.name		= "wdt_pci",
	.id_table	= wdtpci_pci_tbl,
	.probe		= wdtpci_init_one,
	.remove		= __devexit_p(wdtpci_remove_one),
};


/**
 *	wdtpci_cleanup:
 *
 *	Unload the watchdog. You cannot do this with any file handles open.
 *	If your watchdog is set to continue ticking on close and you unload
 *	it, well it keeps ticking. We won't get the interrupt but the board
 *	will not touch PC memory so all is fine. You just have to load a new
 *	module in xx seconds or reboot.
 */

static void __exit wdtpci_cleanup(void)
{
	pci_unregister_driver (&wdtpci_driver);
}


/**
 * 	wdtpci_init:
 *
 *	Set up the WDT watchdog board. All we have to do is grab the
 *	resources we require and bitch if anyone beat us to them.
 *	The open() function will actually kick the board off.
 */

static int __init wdtpci_init(void)
{
	return pci_register_driver (&wdtpci_driver);
}


module_init(wdtpci_init);
module_exit(wdtpci_cleanup);

MODULE_AUTHOR("JP Nollmann, Alan Cox");
MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS_MISCDEV(TEMP_MINOR);