X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fwatchdog%2Fpcwd_usb.c;fp=kernel%2Fdrivers%2Fwatchdog%2Fpcwd_usb.c;h=1a11aedc4fe850738bfe17d469232da64959b84d;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git

diff --git a/kernel/drivers/watchdog/pcwd_usb.c b/kernel/drivers/watchdog/pcwd_usb.c
new file mode 100644
index 000000000..1a11aedc4
--- /dev/null
+++ b/kernel/drivers/watchdog/pcwd_usb.c
@@ -0,0 +1,810 @@
+/*
+ *	Berkshire USB-PC Watchdog Card Driver
+ *
+ *	(c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>.
+ *
+ *	Based on source code of the following authors:
+ *	  Ken Hollis <kenji@bitgate.com>,
+ *	  Alan Cox <alan@lxorguk.ukuu.org.uk>,
+ *	  Matt Domsch <Matt_Domsch@dell.com>,
+ *	  Rob Radez <rob@osinvestor.com>,
+ *	  Greg Kroah-Hartman <greg@kroah.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 Wim Van Sebroeck nor Iguana vzw. admit liability nor
+ *	provide warranty for any of this software. This material is
+ *	provided "AS-IS" and at no charge.
+ *
+ *	Thanks also to Simon Machell at Berkshire Products Inc. for
+ *	providing the test hardware. More info is available at
+ *	http://www.berkprod.com/ or http://www.pcwatchdog.com/
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>	/* For module specific items */
+#include <linux/moduleparam.h>	/* For new moduleparam's */
+#include <linux/types.h>	/* For standard types (like size_t) */
+#include <linux/errno.h>	/* For the -ENODEV/... values */
+#include <linux/kernel.h>	/* For printk/panic/... */
+#include <linux/delay.h>	/* For mdelay function */
+#include <linux/miscdevice.h>	/* For struct miscdevice */
+#include <linux/watchdog.h>	/* For the watchdog specific items */
+#include <linux/notifier.h>	/* For notifier support */
+#include <linux/reboot.h>	/* For reboot_notifier stuff */
+#include <linux/init.h>		/* For __init/__exit/... */
+#include <linux/fs.h>		/* For file operations */
+#include <linux/usb.h>		/* For USB functions */
+#include <linux/slab.h>		/* For kmalloc, ... */
+#include <linux/mutex.h>	/* For mutex locking */
+#include <linux/hid.h>		/* For HID_REQ_SET_REPORT & HID_DT_REPORT */
+#include <linux/uaccess.h>	/* For copy_to_user/put_user/... */
+
+
+/* Module and Version Information */
+#define DRIVER_VERSION "1.02"
+#define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
+#define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
+#define DRIVER_LICENSE "GPL"
+#define DRIVER_NAME "pcwd_usb"
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE(DRIVER_LICENSE);
+
+#define WATCHDOG_HEARTBEAT 0	/* default heartbeat =
+						delay-time from dip-switches */
+static int heartbeat = WATCHDOG_HEARTBEAT;
+module_param(heartbeat, int, 0);
+MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
+	"(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
+				__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
+
+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) ")");
+
+/* The vendor and product id's for the USB-PC Watchdog card */
+#define USB_PCWD_VENDOR_ID	0x0c98
+#define USB_PCWD_PRODUCT_ID	0x1140
+
+/* table of devices that work with this driver */
+static struct usb_device_id usb_pcwd_table[] = {
+	{ USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
+	{ }					/* Terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, usb_pcwd_table);
+
+/* according to documentation max. time to process a command for the USB
+ * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
+#define USB_COMMAND_TIMEOUT	250
+
+/* Watchdog's internal commands */
+#define CMD_READ_TEMP			0x02	/* Read Temperature;
+							Re-trigger Watchdog */
+#define CMD_TRIGGER			CMD_READ_TEMP
+#define CMD_GET_STATUS			0x04	/* Get Status Information */
+#define CMD_GET_FIRMWARE_VERSION	0x08	/* Get Firmware Version */
+#define CMD_GET_DIP_SWITCH_SETTINGS	0x0c	/* Get Dip Switch Settings */
+#define CMD_READ_WATCHDOG_TIMEOUT	0x18	/* Read Current Watchdog Time */
+#define CMD_WRITE_WATCHDOG_TIMEOUT	0x19	/* Write Current WatchdogTime */
+#define CMD_ENABLE_WATCHDOG		0x30	/* Enable / Disable Watchdog */
+#define CMD_DISABLE_WATCHDOG		CMD_ENABLE_WATCHDOG
+
+/* Watchdog's Dip Switch heartbeat values */
+static const int heartbeat_tbl[] = {
+	5,	/* OFF-OFF-OFF	=  5 Sec  */
+	10,	/* OFF-OFF-ON	= 10 Sec  */
+	30,	/* OFF-ON-OFF	= 30 Sec  */
+	60,	/* OFF-ON-ON	=  1 Min  */
+	300,	/* ON-OFF-OFF	=  5 Min  */
+	600,	/* ON-OFF-ON	= 10 Min  */
+	1800,	/* ON-ON-OFF	= 30 Min  */
+	3600,	/* ON-ON-ON	=  1 hour */
+};
+
+/* We can only use 1 card due to the /dev/watchdog restriction */
+static int cards_found;
+
+/* some internal variables */
+static unsigned long is_active;
+static char expect_release;
+
+/* Structure to hold all of our device specific stuff */
+struct usb_pcwd_private {
+	/* save off the usb device pointer */
+	struct usb_device	*udev;
+	/* the interface for this device */
+	struct usb_interface	*interface;
+
+	/* the interface number used for cmd's */
+	unsigned int		interface_number;
+
+	/* the buffer to intr data */
+	unsigned char		*intr_buffer;
+	/* the dma address for the intr buffer */
+	dma_addr_t		intr_dma;
+	/* the size of the intr buffer */
+	size_t			intr_size;
+	/* the urb used for the intr pipe */
+	struct urb		*intr_urb;
+
+	/* The command that is reported back */
+	unsigned char		cmd_command;
+	/* The data MSB that is reported back */
+	unsigned char		cmd_data_msb;
+	/* The data LSB that is reported back */
+	unsigned char		cmd_data_lsb;
+	/* true if we received a report after a command */
+	atomic_t		cmd_received;
+
+	/* Wether or not the device exists */
+	int			exists;
+	/* locks this structure */
+	struct mutex		mtx;
+};
+static struct usb_pcwd_private *usb_pcwd_device;
+
+/* prevent races between open() and disconnect() */
+static DEFINE_MUTEX(disconnect_mutex);
+
+/* local function prototypes */
+static int usb_pcwd_probe(struct usb_interface *interface,
+						const struct usb_device_id *id);
+static void usb_pcwd_disconnect(struct usb_interface *interface);
+
+/* usb specific object needed to register this driver with the usb subsystem */
+static struct usb_driver usb_pcwd_driver = {
+	.name =		DRIVER_NAME,
+	.probe =	usb_pcwd_probe,
+	.disconnect =	usb_pcwd_disconnect,
+	.id_table =	usb_pcwd_table,
+};
+
+
+static void usb_pcwd_intr_done(struct urb *urb)
+{
+	struct usb_pcwd_private *usb_pcwd =
+				(struct usb_pcwd_private *)urb->context;
+	unsigned char *data = usb_pcwd->intr_buffer;
+	struct device *dev = &usb_pcwd->interface->dev;
+	int retval;
+
+	switch (urb->status) {
+	case 0:			/* success */
+		break;
+	case -ECONNRESET:	/* unlink */
+	case -ENOENT:
+	case -ESHUTDOWN:
+		/* this urb is terminated, clean up */
+		dev_dbg(dev, "%s - urb shutting down with status: %d",
+			__func__, urb->status);
+		return;
+	/* -EPIPE:  should clear the halt */
+	default:		/* error */
+		dev_dbg(dev, "%s - nonzero urb status received: %d",
+			__func__, urb->status);
+		goto resubmit;
+	}
+
+	dev_dbg(dev, "received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
+		data[0], data[1], data[2]);
+
+	usb_pcwd->cmd_command  = data[0];
+	usb_pcwd->cmd_data_msb = data[1];
+	usb_pcwd->cmd_data_lsb = data[2];
+
+	/* notify anyone waiting that the cmd has finished */
+	atomic_set(&usb_pcwd->cmd_received, 1);
+
+resubmit:
+	retval = usb_submit_urb(urb, GFP_ATOMIC);
+	if (retval)
+		pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n",
+		       retval);
+}
+
+static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
+		unsigned char cmd, unsigned char *msb, unsigned char *lsb)
+{
+	int got_response, count;
+	unsigned char *buf;
+
+	/* We will not send any commands if the USB PCWD device does
+	 * not exist */
+	if ((!usb_pcwd) || (!usb_pcwd->exists))
+		return -1;
+
+	buf = kmalloc(6, GFP_KERNEL);
+	if (buf == NULL)
+		return 0;
+
+	/* The USB PC Watchdog uses a 6 byte report format.
+	 * The board currently uses only 3 of the six bytes of the report. */
+	buf[0] = cmd;			/* Byte 0 = CMD */
+	buf[1] = *msb;			/* Byte 1 = Data MSB */
+	buf[2] = *lsb;			/* Byte 2 = Data LSB */
+	buf[3] = buf[4] = buf[5] = 0;	/* All other bytes not used */
+
+	dev_dbg(&usb_pcwd->interface->dev,
+		"sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
+		buf[0], buf[1], buf[2]);
+
+	atomic_set(&usb_pcwd->cmd_received, 0);
+
+	if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
+			HID_REQ_SET_REPORT, HID_DT_REPORT,
+			0x0200, usb_pcwd->interface_number, buf, 6,
+			USB_COMMAND_TIMEOUT) != 6) {
+		dev_dbg(&usb_pcwd->interface->dev,
+			"usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n",
+			cmd, *msb, *lsb);
+	}
+	/* wait till the usb card processed the command,
+	 * with a max. timeout of USB_COMMAND_TIMEOUT */
+	got_response = 0;
+	for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response);
+								count++) {
+		mdelay(1);
+		if (atomic_read(&usb_pcwd->cmd_received))
+			got_response = 1;
+	}
+
+	if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
+		/* read back response */
+		*msb = usb_pcwd->cmd_data_msb;
+		*lsb = usb_pcwd->cmd_data_lsb;
+	}
+
+	kfree(buf);
+
+	return got_response;
+}
+
+static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
+{
+	unsigned char msb = 0x00;
+	unsigned char lsb = 0x00;
+	int retval;
+
+	/* Enable Watchdog */
+	retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG,
+								&msb, &lsb);
+
+	if ((retval == 0) || (lsb == 0)) {
+		pr_err("Card did not acknowledge enable attempt\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
+{
+	unsigned char msb = 0xA5;
+	unsigned char lsb = 0xC3;
+	int retval;
+
+	/* Disable Watchdog */
+	retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG,
+								&msb, &lsb);
+
+	if ((retval == 0) || (lsb != 0)) {
+		pr_err("Card did not acknowledge disable attempt\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
+{
+	unsigned char dummy;
+
+	/* Re-trigger Watchdog */
+	usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
+
+	return 0;
+}
+
+static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
+{
+	unsigned char msb = t / 256;
+	unsigned char lsb = t % 256;
+
+	if ((t < 0x0001) || (t > 0xFFFF))
+		return -EINVAL;
+
+	/* Write new heartbeat to watchdog */
+	usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
+
+	heartbeat = t;
+	return 0;
+}
+
+static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd,
+							int *temperature)
+{
+	unsigned char msb, lsb;
+
+	usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
+
+	/*
+	 * Convert celsius to fahrenheit, since this was
+	 * the decided 'standard' for this return value.
+	 */
+	*temperature = (lsb * 9 / 5) + 32;
+
+	return 0;
+}
+
+static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
+								int *time_left)
+{
+	unsigned char msb, lsb;
+
+	/* Read the time that's left before rebooting */
+	/* Note: if the board is not yet armed then we will read 0xFFFF */
+	usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
+
+	*time_left = (msb << 8) + lsb;
+
+	return 0;
+}
+
+/*
+ *	/dev/watchdog handling
+ */
+
+static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
+						size_t len, loff_t *ppos)
+{
+	/* See if we got the magic character 'V' and reload the timer */
+	if (len) {
+		if (!nowayout) {
+			size_t i;
+
+			/* note: just in case someone wrote the magic character
+			 * five months ago... */
+			expect_release = 0;
+
+			/* scan to see whether or not we got the
+			 * magic character */
+			for (i = 0; i != len; i++) {
+				char c;
+				if (get_user(c, data + i))
+					return -EFAULT;
+				if (c == 'V')
+					expect_release = 42;
+			}
+		}
+
+		/* someone wrote to us, we should reload the timer */
+		usb_pcwd_keepalive(usb_pcwd_device);
+	}
+	return len;
+}
+
+static long usb_pcwd_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 =		DRIVER_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_GETTEMP:
+	{
+		int temperature;
+
+		if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
+			return -EFAULT;
+
+		return put_user(temperature, p);
+	}
+
+	case WDIOC_SETOPTIONS:
+	{
+		int new_options, retval = -EINVAL;
+
+		if (get_user(new_options, p))
+			return -EFAULT;
+
+		if (new_options & WDIOS_DISABLECARD) {
+			usb_pcwd_stop(usb_pcwd_device);
+			retval = 0;
+		}
+
+		if (new_options & WDIOS_ENABLECARD) {
+			usb_pcwd_start(usb_pcwd_device);
+			retval = 0;
+		}
+
+		return retval;
+	}
+
+	case WDIOC_KEEPALIVE:
+		usb_pcwd_keepalive(usb_pcwd_device);
+		return 0;
+
+	case WDIOC_SETTIMEOUT:
+	{
+		int new_heartbeat;
+
+		if (get_user(new_heartbeat, p))
+			return -EFAULT;
+
+		if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
+			return -EINVAL;
+
+		usb_pcwd_keepalive(usb_pcwd_device);
+		/* Fall */
+	}
+
+	case WDIOC_GETTIMEOUT:
+		return put_user(heartbeat, p);
+
+	case WDIOC_GETTIMELEFT:
+	{
+		int time_left;
+
+		if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
+			return -EFAULT;
+
+		return put_user(time_left, p);
+	}
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+static int usb_pcwd_open(struct inode *inode, struct file *file)
+{
+	/* /dev/watchdog can only be opened once */
+	if (test_and_set_bit(0, &is_active))
+		return -EBUSY;
+
+	/* Activate */
+	usb_pcwd_start(usb_pcwd_device);
+	usb_pcwd_keepalive(usb_pcwd_device);
+	return nonseekable_open(inode, file);
+}
+
+static int usb_pcwd_release(struct inode *inode, struct file *file)
+{
+	/*
+	 *      Shut off the timer.
+	 */
+	if (expect_release == 42) {
+		usb_pcwd_stop(usb_pcwd_device);
+	} else {
+		pr_crit("Unexpected close, not stopping watchdog!\n");
+		usb_pcwd_keepalive(usb_pcwd_device);
+	}
+	expect_release = 0;
+	clear_bit(0, &is_active);
+	return 0;
+}
+
+/*
+ *	/dev/temperature handling
+ */
+
+static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
+				size_t len, loff_t *ppos)
+{
+	int temperature;
+
+	if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
+		return -EFAULT;
+
+	if (copy_to_user(data, &temperature, 1))
+		return -EFAULT;
+
+	return 1;
+}
+
+static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
+{
+	return nonseekable_open(inode, file);
+}
+
+static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
+{
+	return 0;
+}
+
+/*
+ *	Notify system
+ */
+
+static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
+								void *unused)
+{
+	if (code == SYS_DOWN || code == SYS_HALT)
+		usb_pcwd_stop(usb_pcwd_device);	/* Turn the WDT off */
+
+	return NOTIFY_DONE;
+}
+
+/*
+ *	Kernel Interfaces
+ */
+
+static const struct file_operations usb_pcwd_fops = {
+	.owner =	THIS_MODULE,
+	.llseek =	no_llseek,
+	.write =	usb_pcwd_write,
+	.unlocked_ioctl = usb_pcwd_ioctl,
+	.open =		usb_pcwd_open,
+	.release =	usb_pcwd_release,
+};
+
+static struct miscdevice usb_pcwd_miscdev = {
+	.minor =	WATCHDOG_MINOR,
+	.name =		"watchdog",
+	.fops =		&usb_pcwd_fops,
+};
+
+static const struct file_operations usb_pcwd_temperature_fops = {
+	.owner =	THIS_MODULE,
+	.llseek =	no_llseek,
+	.read =		usb_pcwd_temperature_read,
+	.open =		usb_pcwd_temperature_open,
+	.release =	usb_pcwd_temperature_release,
+};
+
+static struct miscdevice usb_pcwd_temperature_miscdev = {
+	.minor =	TEMP_MINOR,
+	.name =		"temperature",
+	.fops =		&usb_pcwd_temperature_fops,
+};
+
+static struct notifier_block usb_pcwd_notifier = {
+	.notifier_call =	usb_pcwd_notify_sys,
+};
+
+/**
+ *	usb_pcwd_delete
+ */
+static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
+{
+	usb_free_urb(usb_pcwd->intr_urb);
+	if (usb_pcwd->intr_buffer != NULL)
+		usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
+				  usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
+	kfree(usb_pcwd);
+}
+
+/**
+ *	usb_pcwd_probe
+ *
+ *	Called by the usb core when a new device is connected that it thinks
+ *	this driver might be interested in.
+ */
+static int usb_pcwd_probe(struct usb_interface *interface,
+						const struct usb_device_id *id)
+{
+	struct usb_device *udev = interface_to_usbdev(interface);
+	struct usb_host_interface *iface_desc;
+	struct usb_endpoint_descriptor *endpoint;
+	struct usb_pcwd_private *usb_pcwd = NULL;
+	int pipe, maxp;
+	int retval = -ENOMEM;
+	int got_fw_rev;
+	unsigned char fw_rev_major, fw_rev_minor;
+	char fw_ver_str[20];
+	unsigned char option_switches, dummy;
+
+	cards_found++;
+	if (cards_found > 1) {
+		pr_err("This driver only supports 1 device\n");
+		return -ENODEV;
+	}
+
+	/* get the active interface descriptor */
+	iface_desc = interface->cur_altsetting;
+
+	/* check out that we have a HID device */
+	if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
+		pr_err("The device isn't a Human Interface Device\n");
+		return -ENODEV;
+	}
+
+	/* check out the endpoint: it has to be Interrupt & IN */
+	endpoint = &iface_desc->endpoint[0].desc;
+
+	if (!usb_endpoint_is_int_in(endpoint)) {
+		/* we didn't find a Interrupt endpoint with direction IN */
+		pr_err("Couldn't find an INTR & IN endpoint\n");
+		return -ENODEV;
+	}
+
+	/* get a handle to the interrupt data pipe */
+	pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
+	maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
+
+	/* allocate memory for our device and initialize it */
+	usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
+	if (usb_pcwd == NULL)
+		goto error;
+
+	usb_pcwd_device = usb_pcwd;
+
+	mutex_init(&usb_pcwd->mtx);
+	usb_pcwd->udev = udev;
+	usb_pcwd->interface = interface;
+	usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
+	usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
+				le16_to_cpu(endpoint->wMaxPacketSize) : 8);
+
+	/* set up the memory buffer's */
+	usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size,
+					GFP_ATOMIC, &usb_pcwd->intr_dma);
+	if (!usb_pcwd->intr_buffer) {
+		pr_err("Out of memory\n");
+		goto error;
+	}
+
+	/* allocate the urb's */
+	usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!usb_pcwd->intr_urb) {
+		pr_err("Out of memory\n");
+		goto error;
+	}
+
+	/* initialise the intr urb's */
+	usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
+			usb_pcwd->intr_buffer, usb_pcwd->intr_size,
+			usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
+	usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
+	usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+	/* register our interrupt URB with the USB system */
+	if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
+		pr_err("Problem registering interrupt URB\n");
+		retval = -EIO; /* failure */
+		goto error;
+	}
+
+	/* The device exists and can be communicated with */
+	usb_pcwd->exists = 1;
+
+	/* disable card */
+	usb_pcwd_stop(usb_pcwd);
+
+	/* Get the Firmware Version */
+	got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
+						&fw_rev_major, &fw_rev_minor);
+	if (got_fw_rev)
+		sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
+	else
+		sprintf(fw_ver_str, "<card no answer>");
+
+	pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str);
+
+	/* Get switch settings */
+	usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
+							&option_switches);
+
+	pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
+		option_switches,
+		((option_switches & 0x10) ? "ON" : "OFF"),
+		((option_switches & 0x08) ? "ON" : "OFF"));
+
+	/* If heartbeat = 0 then we use the heartbeat from the dip-switches */
+	if (heartbeat == 0)
+		heartbeat = heartbeat_tbl[(option_switches & 0x07)];
+
+	/* Check that the heartbeat value is within it's range ;
+	 * if not reset to the default */
+	if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
+		usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
+		pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
+			WATCHDOG_HEARTBEAT);
+	}
+
+	retval = register_reboot_notifier(&usb_pcwd_notifier);
+	if (retval != 0) {
+		pr_err("cannot register reboot notifier (err=%d)\n", retval);
+		goto error;
+	}
+
+	retval = misc_register(&usb_pcwd_temperature_miscdev);
+	if (retval != 0) {
+		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
+		       TEMP_MINOR, retval);
+		goto err_out_unregister_reboot;
+	}
+
+	retval = misc_register(&usb_pcwd_miscdev);
+	if (retval != 0) {
+		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
+		       WATCHDOG_MINOR, retval);
+		goto err_out_misc_deregister;
+	}
+
+	/* we can register the device now, as it is ready */
+	usb_set_intfdata(interface, usb_pcwd);
+
+	pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
+		heartbeat, nowayout);
+
+	return 0;
+
+err_out_misc_deregister:
+	misc_deregister(&usb_pcwd_temperature_miscdev);
+err_out_unregister_reboot:
+	unregister_reboot_notifier(&usb_pcwd_notifier);
+error:
+	if (usb_pcwd)
+		usb_pcwd_delete(usb_pcwd);
+	usb_pcwd_device = NULL;
+	return retval;
+}
+
+
+/**
+ *	usb_pcwd_disconnect
+ *
+ *	Called by the usb core when the device is removed from the system.
+ *
+ *	This routine guarantees that the driver will not submit any more urbs
+ *	by clearing dev->udev.
+ */
+static void usb_pcwd_disconnect(struct usb_interface *interface)
+{
+	struct usb_pcwd_private *usb_pcwd;
+
+	/* prevent races with open() */
+	mutex_lock(&disconnect_mutex);
+
+	usb_pcwd = usb_get_intfdata(interface);
+	usb_set_intfdata(interface, NULL);
+
+	mutex_lock(&usb_pcwd->mtx);
+
+	/* Stop the timer before we leave */
+	if (!nowayout)
+		usb_pcwd_stop(usb_pcwd);
+
+	/* We should now stop communicating with the USB PCWD device */
+	usb_pcwd->exists = 0;
+
+	/* Deregister */
+	misc_deregister(&usb_pcwd_miscdev);
+	misc_deregister(&usb_pcwd_temperature_miscdev);
+	unregister_reboot_notifier(&usb_pcwd_notifier);
+
+	mutex_unlock(&usb_pcwd->mtx);
+
+	/* Delete the USB PCWD device */
+	usb_pcwd_delete(usb_pcwd);
+
+	cards_found--;
+
+	mutex_unlock(&disconnect_mutex);
+
+	pr_info("USB PC Watchdog disconnected\n");
+}
+
+module_usb_driver(usb_pcwd_driver);