2 * Berkshire USB-PC Watchdog Card Driver
4 * (c) Copyright 2004 Wim Van Sebroeck <wim@iguana.be>.
6 * Based on source code of the following authors:
7 * Ken Hollis <kenji@bitgate.com>,
8 * Alan Cox <alan@redhat.com>,
9 * Matt Domsch <Matt_Domsch@dell.com>,
10 * Rob Radez <rob@osinvestor.com>,
11 * Greg Kroah-Hartman <greg@kroah.com>
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
18 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
19 * provide warranty for any of this software. This material is
20 * provided "AS-IS" and at no charge.
22 * Thanks also to Simon Machell at Berkshire Products Inc. for
23 * providing the test hardware. More info is available at
24 * http://www.berkprod.com/ or http://www.pcwatchdog.com/
27 #include <linux/kernel.h>
28 #include <linux/errno.h>
29 #include <linux/init.h>
30 #include <linux/slab.h>
31 #include <linux/module.h>
32 #include <linux/moduleparam.h>
33 #include <linux/types.h>
34 #include <linux/delay.h>
35 #include <linux/miscdevice.h>
36 #include <linux/watchdog.h>
37 #include <linux/notifier.h>
38 #include <linux/reboot.h>
40 #include <linux/smp_lock.h>
41 #include <linux/completion.h>
42 #include <asm/uaccess.h>
43 #include <linux/usb.h>
44 #include <linux/mutex.h>
47 #ifdef CONFIG_USB_DEBUG
53 /* Use our own dbg macro */
55 #define dbg(format, arg...) do { if (debug) printk(KERN_DEBUG PFX format "\n" , ## arg); } while (0)
58 /* Module and Version Information */
59 #define DRIVER_VERSION "1.01"
60 #define DRIVER_DATE "15 Mar 2005"
61 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
62 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
63 #define DRIVER_LICENSE "GPL"
64 #define DRIVER_NAME "pcwd_usb"
65 #define PFX DRIVER_NAME ": "
67 MODULE_AUTHOR(DRIVER_AUTHOR);
68 MODULE_DESCRIPTION(DRIVER_DESC);
69 MODULE_LICENSE(DRIVER_LICENSE);
70 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
71 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
73 /* Module Parameters */
74 module_param(debug, int, 0);
75 MODULE_PARM_DESC(debug, "Debug enabled or not");
77 #define WATCHDOG_HEARTBEAT 2 /* 2 sec default heartbeat */
78 static int heartbeat = WATCHDOG_HEARTBEAT;
79 module_param(heartbeat, int, 0);
80 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
82 static int nowayout = WATCHDOG_NOWAYOUT;
83 module_param(nowayout, int, 0);
84 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
86 /* The vendor and product id's for the USB-PC Watchdog card */
87 #define USB_PCWD_VENDOR_ID 0x0c98
88 #define USB_PCWD_PRODUCT_ID 0x1140
90 /* table of devices that work with this driver */
91 static struct usb_device_id usb_pcwd_table [] = {
92 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
93 { } /* Terminating entry */
95 MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
97 /* according to documentation max. time to process a command for the USB
98 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
99 #define USB_COMMAND_TIMEOUT 250
101 /* Watchdog's internal commands */
102 #define CMD_READ_TEMP 0x02 /* Read Temperature; Re-trigger Watchdog */
103 #define CMD_TRIGGER CMD_READ_TEMP
104 #define CMD_GET_STATUS 0x04 /* Get Status Information */
105 #define CMD_GET_FIRMWARE_VERSION 0x08 /* Get Firmware Version */
106 #define CMD_GET_DIP_SWITCH_SETTINGS 0x0c /* Get Dip Switch Settings */
107 #define CMD_READ_WATCHDOG_TIMEOUT 0x18 /* Read Current Watchdog Time */
108 #define CMD_WRITE_WATCHDOG_TIMEOUT 0x19 /* Write Current Watchdog Time */
109 #define CMD_ENABLE_WATCHDOG 0x30 /* Enable / Disable Watchdog */
110 #define CMD_DISABLE_WATCHDOG CMD_ENABLE_WATCHDOG
112 /* Some defines that I like to be somewhere else like include/linux/usb_hid.h */
113 #define HID_REQ_SET_REPORT 0x09
114 #define HID_DT_REPORT (USB_TYPE_CLASS | 0x02)
116 /* We can only use 1 card due to the /dev/watchdog restriction */
117 static int cards_found;
119 /* some internal variables */
120 static unsigned long is_active;
121 static char expect_release;
123 /* Structure to hold all of our device specific stuff */
124 struct usb_pcwd_private {
125 struct usb_device * udev; /* save off the usb device pointer */
126 struct usb_interface * interface; /* the interface for this device */
128 unsigned int interface_number; /* the interface number used for cmd's */
130 unsigned char * intr_buffer; /* the buffer to intr data */
131 dma_addr_t intr_dma; /* the dma address for the intr buffer */
132 size_t intr_size; /* the size of the intr buffer */
133 struct urb * intr_urb; /* the urb used for the intr pipe */
135 unsigned char cmd_command; /* The command that is reported back */
136 unsigned char cmd_data_msb; /* The data MSB that is reported back */
137 unsigned char cmd_data_lsb; /* The data LSB that is reported back */
138 atomic_t cmd_received; /* true if we received a report after a command */
140 int exists; /* Wether or not the device exists */
141 struct semaphore sem; /* locks this structure */
143 static struct usb_pcwd_private *usb_pcwd_device;
145 /* prevent races between open() and disconnect() */
146 static DEFINE_MUTEX(disconnect_mutex);
148 /* local function prototypes */
149 static int usb_pcwd_probe (struct usb_interface *interface, const struct usb_device_id *id);
150 static void usb_pcwd_disconnect (struct usb_interface *interface);
152 /* usb specific object needed to register this driver with the usb subsystem */
153 static struct usb_driver usb_pcwd_driver = {
155 .probe = usb_pcwd_probe,
156 .disconnect = usb_pcwd_disconnect,
157 .id_table = usb_pcwd_table,
161 static void usb_pcwd_intr_done(struct urb *urb)
163 struct usb_pcwd_private *usb_pcwd = (struct usb_pcwd_private *)urb->context;
164 unsigned char *data = usb_pcwd->intr_buffer;
167 switch (urb->status) {
168 case 0: /* success */
170 case -ECONNRESET: /* unlink */
173 /* this urb is terminated, clean up */
174 dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
176 /* -EPIPE: should clear the halt */
178 dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
182 dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
183 data[0], data[1], data[2]);
185 usb_pcwd->cmd_command = data[0];
186 usb_pcwd->cmd_data_msb = data[1];
187 usb_pcwd->cmd_data_lsb = data[2];
189 /* notify anyone waiting that the cmd has finished */
190 atomic_set (&usb_pcwd->cmd_received, 1);
193 retval = usb_submit_urb (urb, GFP_ATOMIC);
195 printk(KERN_ERR PFX "can't resubmit intr, usb_submit_urb failed with result %d\n",
199 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, unsigned char cmd,
200 unsigned char *msb, unsigned char *lsb)
202 int got_response, count;
203 unsigned char buf[6];
205 /* We will not send any commands if the USB PCWD device does not exist */
206 if ((!usb_pcwd) || (!usb_pcwd->exists))
209 /* The USB PC Watchdog uses a 6 byte report format. The board currently uses
210 * only 3 of the six bytes of the report. */
211 buf[0] = cmd; /* Byte 0 = CMD */
212 buf[1] = *msb; /* Byte 1 = Data MSB */
213 buf[2] = *lsb; /* Byte 2 = Data LSB */
214 buf[3] = buf[4] = buf[5] = 0; /* All other bytes not used */
216 dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
217 buf[0], buf[1], buf[2]);
219 atomic_set (&usb_pcwd->cmd_received, 0);
221 if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
222 HID_REQ_SET_REPORT, HID_DT_REPORT,
223 0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
224 USB_COMMAND_TIMEOUT) != sizeof(buf)) {
225 dbg("usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
227 /* wait till the usb card processed the command,
228 * with a max. timeout of USB_COMMAND_TIMEOUT */
230 for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); count++) {
232 if (atomic_read (&usb_pcwd->cmd_received))
236 if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
237 /* read back response */
238 *msb = usb_pcwd->cmd_data_msb;
239 *lsb = usb_pcwd->cmd_data_lsb;
245 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
247 unsigned char msb = 0x00;
248 unsigned char lsb = 0x00;
251 /* Enable Watchdog */
252 retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, &msb, &lsb);
254 if ((retval == 0) || (lsb == 0)) {
255 printk(KERN_ERR PFX "Card did not acknowledge enable attempt\n");
262 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
264 unsigned char msb = 0xA5;
265 unsigned char lsb = 0xC3;
268 /* Disable Watchdog */
269 retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, &msb, &lsb);
271 if ((retval == 0) || (lsb != 0)) {
272 printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
279 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
283 /* Re-trigger Watchdog */
284 usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
289 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
291 unsigned char msb = t / 256;
292 unsigned char lsb = t % 256;
294 if ((t < 0x0001) || (t > 0xFFFF))
297 /* Write new heartbeat to watchdog */
298 usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
304 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature)
306 unsigned char msb, lsb;
308 usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
311 * Convert celsius to fahrenheit, since this was
312 * the decided 'standard' for this return value.
314 *temperature = (lsb * 9 / 5) + 32;
319 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, int *time_left)
321 unsigned char msb, lsb;
323 /* Read the time that's left before rebooting */
324 /* Note: if the board is not yet armed then we will read 0xFFFF */
325 usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
327 *time_left = (msb << 8) + lsb;
333 * /dev/watchdog handling
336 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
337 size_t len, loff_t *ppos)
339 /* See if we got the magic character 'V' and reload the timer */
344 /* note: just in case someone wrote the magic character
345 * five months ago... */
348 /* scan to see whether or not we got the magic character */
349 for (i = 0; i != len; i++) {
351 if(get_user(c, data+i))
358 /* someone wrote to us, we should reload the timer */
359 usb_pcwd_keepalive(usb_pcwd_device);
364 static int usb_pcwd_ioctl(struct inode *inode, struct file *file,
365 unsigned int cmd, unsigned long arg)
367 void __user *argp = (void __user *)arg;
368 int __user *p = argp;
369 static struct watchdog_info ident = {
370 .options = WDIOF_KEEPALIVEPING |
373 .firmware_version = 1,
374 .identity = DRIVER_NAME,
378 case WDIOC_GETSUPPORT:
379 return copy_to_user(argp, &ident,
380 sizeof (ident)) ? -EFAULT : 0;
382 case WDIOC_GETSTATUS:
383 case WDIOC_GETBOOTSTATUS:
384 return put_user(0, p);
390 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
393 return put_user(temperature, p);
396 case WDIOC_KEEPALIVE:
397 usb_pcwd_keepalive(usb_pcwd_device);
400 case WDIOC_SETOPTIONS:
402 int new_options, retval = -EINVAL;
404 if (get_user (new_options, p))
407 if (new_options & WDIOS_DISABLECARD) {
408 usb_pcwd_stop(usb_pcwd_device);
412 if (new_options & WDIOS_ENABLECARD) {
413 usb_pcwd_start(usb_pcwd_device);
420 case WDIOC_SETTIMEOUT:
424 if (get_user(new_heartbeat, p))
427 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
430 usb_pcwd_keepalive(usb_pcwd_device);
434 case WDIOC_GETTIMEOUT:
435 return put_user(heartbeat, p);
437 case WDIOC_GETTIMELEFT:
441 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
444 return put_user(time_left, p);
452 static int usb_pcwd_open(struct inode *inode, struct file *file)
454 /* /dev/watchdog can only be opened once */
455 if (test_and_set_bit(0, &is_active))
459 usb_pcwd_start(usb_pcwd_device);
460 usb_pcwd_keepalive(usb_pcwd_device);
461 return nonseekable_open(inode, file);
464 static int usb_pcwd_release(struct inode *inode, struct file *file)
467 * Shut off the timer.
469 if (expect_release == 42) {
470 usb_pcwd_stop(usb_pcwd_device);
472 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
473 usb_pcwd_keepalive(usb_pcwd_device);
476 clear_bit(0, &is_active);
481 * /dev/temperature handling
484 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
485 size_t len, loff_t *ppos)
489 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
492 if (copy_to_user(data, &temperature, 1))
498 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
500 return nonseekable_open(inode, file);
503 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
512 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
514 if (code==SYS_DOWN || code==SYS_HALT) {
515 /* Turn the WDT off */
516 usb_pcwd_stop(usb_pcwd_device);
526 static const struct file_operations usb_pcwd_fops = {
527 .owner = THIS_MODULE,
529 .write = usb_pcwd_write,
530 .ioctl = usb_pcwd_ioctl,
531 .open = usb_pcwd_open,
532 .release = usb_pcwd_release,
535 static struct miscdevice usb_pcwd_miscdev = {
536 .minor = WATCHDOG_MINOR,
538 .fops = &usb_pcwd_fops,
541 static const struct file_operations usb_pcwd_temperature_fops = {
542 .owner = THIS_MODULE,
544 .read = usb_pcwd_temperature_read,
545 .open = usb_pcwd_temperature_open,
546 .release = usb_pcwd_temperature_release,
549 static struct miscdevice usb_pcwd_temperature_miscdev = {
551 .name = "temperature",
552 .fops = &usb_pcwd_temperature_fops,
555 static struct notifier_block usb_pcwd_notifier = {
556 .notifier_call = usb_pcwd_notify_sys,
562 static inline void usb_pcwd_delete (struct usb_pcwd_private *usb_pcwd)
564 if (usb_pcwd->intr_urb != NULL)
565 usb_free_urb (usb_pcwd->intr_urb);
566 if (usb_pcwd->intr_buffer != NULL)
567 usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
568 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
575 * Called by the usb core when a new device is connected that it thinks
576 * this driver might be interested in.
578 static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
580 struct usb_device *udev = interface_to_usbdev(interface);
581 struct usb_host_interface *iface_desc;
582 struct usb_endpoint_descriptor *endpoint;
583 struct usb_pcwd_private *usb_pcwd = NULL;
585 int retval = -ENOMEM;
587 unsigned char fw_rev_major, fw_rev_minor;
589 unsigned char option_switches, dummy;
592 if (cards_found > 1) {
593 printk(KERN_ERR PFX "This driver only supports 1 device\n");
597 /* get the active interface descriptor */
598 iface_desc = interface->cur_altsetting;
600 /* check out that we have a HID device */
601 if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
602 printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
606 /* check out the endpoint: it has to be Interrupt & IN */
607 endpoint = &iface_desc->endpoint[0].desc;
609 if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
610 ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
611 == USB_ENDPOINT_XFER_INT))) {
612 /* we didn't find a Interrupt endpoint with direction IN */
613 printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
617 /* get a handle to the interrupt data pipe */
618 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
619 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
621 /* allocate memory for our device and initialize it */
622 usb_pcwd = kmalloc (sizeof(struct usb_pcwd_private), GFP_KERNEL);
623 if (usb_pcwd == NULL) {
624 printk(KERN_ERR PFX "Out of memory\n");
627 memset (usb_pcwd, 0x00, sizeof (*usb_pcwd));
629 usb_pcwd_device = usb_pcwd;
631 init_MUTEX (&usb_pcwd->sem);
632 usb_pcwd->udev = udev;
633 usb_pcwd->interface = interface;
634 usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
635 usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? le16_to_cpu(endpoint->wMaxPacketSize) : 8);
637 /* set up the memory buffer's */
638 if (!(usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, SLAB_ATOMIC, &usb_pcwd->intr_dma))) {
639 printk(KERN_ERR PFX "Out of memory\n");
643 /* allocate the urb's */
644 usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
645 if (!usb_pcwd->intr_urb) {
646 printk(KERN_ERR PFX "Out of memory\n");
650 /* initialise the intr urb's */
651 usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
652 usb_pcwd->intr_buffer, usb_pcwd->intr_size,
653 usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
654 usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
655 usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
657 /* register our interrupt URB with the USB system */
658 if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
659 printk(KERN_ERR PFX "Problem registering interrupt URB\n");
660 retval = -EIO; /* failure */
664 /* The device exists and can be communicated with */
665 usb_pcwd->exists = 1;
668 usb_pcwd_stop(usb_pcwd);
670 /* Get the Firmware Version */
671 got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
673 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
675 sprintf(fw_ver_str, "<card no answer>");
678 printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
681 /* Get switch settings */
682 usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);
684 printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
686 ((option_switches & 0x10) ? "ON" : "OFF"),
687 ((option_switches & 0x08) ? "ON" : "OFF"));
689 /* Check that the heartbeat value is within it's range ; if not reset to the default */
690 if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
691 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
692 printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
696 retval = register_reboot_notifier(&usb_pcwd_notifier);
698 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
703 retval = misc_register(&usb_pcwd_temperature_miscdev);
705 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
707 goto err_out_unregister_reboot;
710 retval = misc_register(&usb_pcwd_miscdev);
712 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
713 WATCHDOG_MINOR, retval);
714 goto err_out_misc_deregister;
717 /* we can register the device now, as it is ready */
718 usb_set_intfdata (interface, usb_pcwd);
720 printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
721 heartbeat, nowayout);
725 err_out_misc_deregister:
726 misc_deregister(&usb_pcwd_temperature_miscdev);
727 err_out_unregister_reboot:
728 unregister_reboot_notifier(&usb_pcwd_notifier);
731 usb_pcwd_delete(usb_pcwd);
732 usb_pcwd_device = NULL;
738 * usb_pcwd_disconnect
740 * Called by the usb core when the device is removed from the system.
742 * This routine guarantees that the driver will not submit any more urbs
743 * by clearing dev->udev.
745 static void usb_pcwd_disconnect(struct usb_interface *interface)
747 struct usb_pcwd_private *usb_pcwd;
749 /* prevent races with open() */
750 mutex_lock(&disconnect_mutex);
752 usb_pcwd = usb_get_intfdata (interface);
753 usb_set_intfdata (interface, NULL);
755 down (&usb_pcwd->sem);
757 /* Stop the timer before we leave */
759 usb_pcwd_stop(usb_pcwd);
761 /* We should now stop communicating with the USB PCWD device */
762 usb_pcwd->exists = 0;
765 misc_deregister(&usb_pcwd_miscdev);
766 misc_deregister(&usb_pcwd_temperature_miscdev);
767 unregister_reboot_notifier(&usb_pcwd_notifier);
771 /* Delete the USB PCWD device */
772 usb_pcwd_delete(usb_pcwd);
776 mutex_unlock(&disconnect_mutex);
778 printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
786 static int __init usb_pcwd_init(void)
790 /* register this driver with the USB subsystem */
791 result = usb_register(&usb_pcwd_driver);
793 printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
798 printk(KERN_INFO PFX DRIVER_DESC " v" DRIVER_VERSION " (" DRIVER_DATE ")\n");
806 static void __exit usb_pcwd_exit(void)
808 /* deregister this driver with the USB subsystem */
809 usb_deregister(&usb_pcwd_driver);
813 module_init (usb_pcwd_init);
814 module_exit (usb_pcwd_exit);