1/*
2 *	Berkshire USB-PC Watchdog Card Driver
3 *
4 *	(c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>.
5 *
6 *	Based on source code of the following authors:
7 *	  Ken Hollis <kenji@bitgate.com>,
8 *	  Alan Cox <alan@lxorguk.ukuu.org.uk>,
9 *	  Matt Domsch <Matt_Domsch@dell.com>,
10 *	  Rob Radez <rob@osinvestor.com>,
11 *	  Greg Kroah-Hartman <greg@kroah.com>
12 *
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.
17 *
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.
21 *
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/
25 */
26
27#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28
29#include <linux/module.h>	/* For module specific items */
30#include <linux/moduleparam.h>	/* For new moduleparam's */
31#include <linux/types.h>	/* For standard types (like size_t) */
32#include <linux/errno.h>	/* For the -ENODEV/... values */
33#include <linux/kernel.h>	/* For printk/panic/... */
34#include <linux/delay.h>	/* For mdelay function */
35#include <linux/miscdevice.h>	/* For struct miscdevice */
36#include <linux/watchdog.h>	/* For the watchdog specific items */
37#include <linux/notifier.h>	/* For notifier support */
38#include <linux/reboot.h>	/* For reboot_notifier stuff */
39#include <linux/init.h>		/* For __init/__exit/... */
40#include <linux/fs.h>		/* For file operations */
41#include <linux/usb.h>		/* For USB functions */
42#include <linux/slab.h>		/* For kmalloc, ... */
43#include <linux/mutex.h>	/* For mutex locking */
44#include <linux/hid.h>		/* For HID_REQ_SET_REPORT & HID_DT_REPORT */
45#include <linux/uaccess.h>	/* For copy_to_user/put_user/... */
46
47
48/* Module and Version Information */
49#define DRIVER_VERSION "1.02"
50#define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
51#define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
52#define DRIVER_LICENSE "GPL"
53#define DRIVER_NAME "pcwd_usb"
54
55MODULE_AUTHOR(DRIVER_AUTHOR);
56MODULE_DESCRIPTION(DRIVER_DESC);
57MODULE_LICENSE(DRIVER_LICENSE);
58
59#define WATCHDOG_HEARTBEAT 0	/* default heartbeat =
60						delay-time from dip-switches */
61static int heartbeat = WATCHDOG_HEARTBEAT;
62module_param(heartbeat, int, 0);
63MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
64	"(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
65				__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
66
67static bool nowayout = WATCHDOG_NOWAYOUT;
68module_param(nowayout, bool, 0);
69MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
70				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
71
72/* The vendor and product id's for the USB-PC Watchdog card */
73#define USB_PCWD_VENDOR_ID	0x0c98
74#define USB_PCWD_PRODUCT_ID	0x1140
75
76/* table of devices that work with this driver */
77static struct usb_device_id usb_pcwd_table[] = {
78	{ USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
79	{ }					/* Terminating entry */
80};
81MODULE_DEVICE_TABLE(usb, usb_pcwd_table);
82
83/* according to documentation max. time to process a command for the USB
84 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
85#define USB_COMMAND_TIMEOUT	250
86
87/* Watchdog's internal commands */
88#define CMD_READ_TEMP			0x02	/* Read Temperature;
89							Re-trigger Watchdog */
90#define CMD_TRIGGER			CMD_READ_TEMP
91#define CMD_GET_STATUS			0x04	/* Get Status Information */
92#define CMD_GET_FIRMWARE_VERSION	0x08	/* Get Firmware Version */
93#define CMD_GET_DIP_SWITCH_SETTINGS	0x0c	/* Get Dip Switch Settings */
94#define CMD_READ_WATCHDOG_TIMEOUT	0x18	/* Read Current Watchdog Time */
95#define CMD_WRITE_WATCHDOG_TIMEOUT	0x19	/* Write Current WatchdogTime */
96#define CMD_ENABLE_WATCHDOG		0x30	/* Enable / Disable Watchdog */
97#define CMD_DISABLE_WATCHDOG		CMD_ENABLE_WATCHDOG
98
99/* Watchdog's Dip Switch heartbeat values */
100static const int heartbeat_tbl[] = {
101	5,	/* OFF-OFF-OFF	=  5 Sec  */
102	10,	/* OFF-OFF-ON	= 10 Sec  */
103	30,	/* OFF-ON-OFF	= 30 Sec  */
104	60,	/* OFF-ON-ON	=  1 Min  */
105	300,	/* ON-OFF-OFF	=  5 Min  */
106	600,	/* ON-OFF-ON	= 10 Min  */
107	1800,	/* ON-ON-OFF	= 30 Min  */
108	3600,	/* ON-ON-ON	=  1 hour */
109};
110
111/* We can only use 1 card due to the /dev/watchdog restriction */
112static int cards_found;
113
114/* some internal variables */
115static unsigned long is_active;
116static char expect_release;
117
118/* Structure to hold all of our device specific stuff */
119struct usb_pcwd_private {
120	/* save off the usb device pointer */
121	struct usb_device	*udev;
122	/* the interface for this device */
123	struct usb_interface	*interface;
124
125	/* the interface number used for cmd's */
126	unsigned int		interface_number;
127
128	/* the buffer to intr data */
129	unsigned char		*intr_buffer;
130	/* the dma address for the intr buffer */
131	dma_addr_t		intr_dma;
132	/* the size of the intr buffer */
133	size_t			intr_size;
134	/* the urb used for the intr pipe */
135	struct urb		*intr_urb;
136
137	/* The command that is reported back */
138	unsigned char		cmd_command;
139	/* The data MSB that is reported back */
140	unsigned char		cmd_data_msb;
141	/* The data LSB that is reported back */
142	unsigned char		cmd_data_lsb;
143	/* true if we received a report after a command */
144	atomic_t		cmd_received;
145
146	/* Wether or not the device exists */
147	int			exists;
148	/* locks this structure */
149	struct mutex		mtx;
150};
151static struct usb_pcwd_private *usb_pcwd_device;
152
153/* prevent races between open() and disconnect() */
154static DEFINE_MUTEX(disconnect_mutex);
155
156/* local function prototypes */
157static int usb_pcwd_probe(struct usb_interface *interface,
158						const struct usb_device_id *id);
159static void usb_pcwd_disconnect(struct usb_interface *interface);
160
161/* usb specific object needed to register this driver with the usb subsystem */
162static struct usb_driver usb_pcwd_driver = {
163	.name =		DRIVER_NAME,
164	.probe =	usb_pcwd_probe,
165	.disconnect =	usb_pcwd_disconnect,
166	.id_table =	usb_pcwd_table,
167};
168
169
170static void usb_pcwd_intr_done(struct urb *urb)
171{
172	struct usb_pcwd_private *usb_pcwd =
173				(struct usb_pcwd_private *)urb->context;
174	unsigned char *data = usb_pcwd->intr_buffer;
175	struct device *dev = &usb_pcwd->interface->dev;
176	int retval;
177
178	switch (urb->status) {
179	case 0:			/* success */
180		break;
181	case -ECONNRESET:	/* unlink */
182	case -ENOENT:
183	case -ESHUTDOWN:
184		/* this urb is terminated, clean up */
185		dev_dbg(dev, "%s - urb shutting down with status: %d",
186			__func__, urb->status);
187		return;
188	/* -EPIPE:  should clear the halt */
189	default:		/* error */
190		dev_dbg(dev, "%s - nonzero urb status received: %d",
191			__func__, urb->status);
192		goto resubmit;
193	}
194
195	dev_dbg(dev, "received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
196		data[0], data[1], data[2]);
197
198	usb_pcwd->cmd_command  = data[0];
199	usb_pcwd->cmd_data_msb = data[1];
200	usb_pcwd->cmd_data_lsb = data[2];
201
202	/* notify anyone waiting that the cmd has finished */
203	atomic_set(&usb_pcwd->cmd_received, 1);
204
205resubmit:
206	retval = usb_submit_urb(urb, GFP_ATOMIC);
207	if (retval)
208		pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n",
209		       retval);
210}
211
212static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
213		unsigned char cmd, unsigned char *msb, unsigned char *lsb)
214{
215	int got_response, count;
216	unsigned char *buf;
217
218	/* We will not send any commands if the USB PCWD device does
219	 * not exist */
220	if ((!usb_pcwd) || (!usb_pcwd->exists))
221		return -1;
222
223	buf = kmalloc(6, GFP_KERNEL);
224	if (buf == NULL)
225		return 0;
226
227	/* The USB PC Watchdog uses a 6 byte report format.
228	 * The board currently uses only 3 of the six bytes of the report. */
229	buf[0] = cmd;			/* Byte 0 = CMD */
230	buf[1] = *msb;			/* Byte 1 = Data MSB */
231	buf[2] = *lsb;			/* Byte 2 = Data LSB */
232	buf[3] = buf[4] = buf[5] = 0;	/* All other bytes not used */
233
234	dev_dbg(&usb_pcwd->interface->dev,
235		"sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
236		buf[0], buf[1], buf[2]);
237
238	atomic_set(&usb_pcwd->cmd_received, 0);
239
240	if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
241			HID_REQ_SET_REPORT, HID_DT_REPORT,
242			0x0200, usb_pcwd->interface_number, buf, 6,
243			USB_COMMAND_TIMEOUT) != 6) {
244		dev_dbg(&usb_pcwd->interface->dev,
245			"usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n",
246			cmd, *msb, *lsb);
247	}
248	/* wait till the usb card processed the command,
249	 * with a max. timeout of USB_COMMAND_TIMEOUT */
250	got_response = 0;
251	for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response);
252								count++) {
253		mdelay(1);
254		if (atomic_read(&usb_pcwd->cmd_received))
255			got_response = 1;
256	}
257
258	if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
259		/* read back response */
260		*msb = usb_pcwd->cmd_data_msb;
261		*lsb = usb_pcwd->cmd_data_lsb;
262	}
263
264	kfree(buf);
265
266	return got_response;
267}
268
269static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
270{
271	unsigned char msb = 0x00;
272	unsigned char lsb = 0x00;
273	int retval;
274
275	/* Enable Watchdog */
276	retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG,
277								&msb, &lsb);
278
279	if ((retval == 0) || (lsb == 0)) {
280		pr_err("Card did not acknowledge enable attempt\n");
281		return -1;
282	}
283
284	return 0;
285}
286
287static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
288{
289	unsigned char msb = 0xA5;
290	unsigned char lsb = 0xC3;
291	int retval;
292
293	/* Disable Watchdog */
294	retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG,
295								&msb, &lsb);
296
297	if ((retval == 0) || (lsb != 0)) {
298		pr_err("Card did not acknowledge disable attempt\n");
299		return -1;
300	}
301
302	return 0;
303}
304
305static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
306{
307	unsigned char dummy;
308
309	/* Re-trigger Watchdog */
310	usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
311
312	return 0;
313}
314
315static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
316{
317	unsigned char msb = t / 256;
318	unsigned char lsb = t % 256;
319
320	if ((t < 0x0001) || (t > 0xFFFF))
321		return -EINVAL;
322
323	/* Write new heartbeat to watchdog */
324	usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
325
326	heartbeat = t;
327	return 0;
328}
329
330static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd,
331							int *temperature)
332{
333	unsigned char msb, lsb;
334
335	usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
336
337	/*
338	 * Convert celsius to fahrenheit, since this was
339	 * the decided 'standard' for this return value.
340	 */
341	*temperature = (lsb * 9 / 5) + 32;
342
343	return 0;
344}
345
346static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
347								int *time_left)
348{
349	unsigned char msb, lsb;
350
351	/* Read the time that's left before rebooting */
352	/* Note: if the board is not yet armed then we will read 0xFFFF */
353	usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
354
355	*time_left = (msb << 8) + lsb;
356
357	return 0;
358}
359
360/*
361 *	/dev/watchdog handling
362 */
363
364static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
365						size_t len, loff_t *ppos)
366{
367	/* See if we got the magic character 'V' and reload the timer */
368	if (len) {
369		if (!nowayout) {
370			size_t i;
371
372			/* note: just in case someone wrote the magic character
373			 * five months ago... */
374			expect_release = 0;
375
376			/* scan to see whether or not we got the
377			 * magic character */
378			for (i = 0; i != len; i++) {
379				char c;
380				if (get_user(c, data + i))
381					return -EFAULT;
382				if (c == 'V')
383					expect_release = 42;
384			}
385		}
386
387		/* someone wrote to us, we should reload the timer */
388		usb_pcwd_keepalive(usb_pcwd_device);
389	}
390	return len;
391}
392
393static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
394						unsigned long arg)
395{
396	void __user *argp = (void __user *)arg;
397	int __user *p = argp;
398	static const struct watchdog_info ident = {
399		.options =		WDIOF_KEEPALIVEPING |
400					WDIOF_SETTIMEOUT |
401					WDIOF_MAGICCLOSE,
402		.firmware_version =	1,
403		.identity =		DRIVER_NAME,
404	};
405
406	switch (cmd) {
407	case WDIOC_GETSUPPORT:
408		return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
409
410	case WDIOC_GETSTATUS:
411	case WDIOC_GETBOOTSTATUS:
412		return put_user(0, p);
413
414	case WDIOC_GETTEMP:
415	{
416		int temperature;
417
418		if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
419			return -EFAULT;
420
421		return put_user(temperature, p);
422	}
423
424	case WDIOC_SETOPTIONS:
425	{
426		int new_options, retval = -EINVAL;
427
428		if (get_user(new_options, p))
429			return -EFAULT;
430
431		if (new_options & WDIOS_DISABLECARD) {
432			usb_pcwd_stop(usb_pcwd_device);
433			retval = 0;
434		}
435
436		if (new_options & WDIOS_ENABLECARD) {
437			usb_pcwd_start(usb_pcwd_device);
438			retval = 0;
439		}
440
441		return retval;
442	}
443
444	case WDIOC_KEEPALIVE:
445		usb_pcwd_keepalive(usb_pcwd_device);
446		return 0;
447
448	case WDIOC_SETTIMEOUT:
449	{
450		int new_heartbeat;
451
452		if (get_user(new_heartbeat, p))
453			return -EFAULT;
454
455		if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
456			return -EINVAL;
457
458		usb_pcwd_keepalive(usb_pcwd_device);
459		/* Fall */
460	}
461
462	case WDIOC_GETTIMEOUT:
463		return put_user(heartbeat, p);
464
465	case WDIOC_GETTIMELEFT:
466	{
467		int time_left;
468
469		if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
470			return -EFAULT;
471
472		return put_user(time_left, p);
473	}
474
475	default:
476		return -ENOTTY;
477	}
478}
479
480static int usb_pcwd_open(struct inode *inode, struct file *file)
481{
482	/* /dev/watchdog can only be opened once */
483	if (test_and_set_bit(0, &is_active))
484		return -EBUSY;
485
486	/* Activate */
487	usb_pcwd_start(usb_pcwd_device);
488	usb_pcwd_keepalive(usb_pcwd_device);
489	return nonseekable_open(inode, file);
490}
491
492static int usb_pcwd_release(struct inode *inode, struct file *file)
493{
494	/*
495	 *      Shut off the timer.
496	 */
497	if (expect_release == 42) {
498		usb_pcwd_stop(usb_pcwd_device);
499	} else {
500		pr_crit("Unexpected close, not stopping watchdog!\n");
501		usb_pcwd_keepalive(usb_pcwd_device);
502	}
503	expect_release = 0;
504	clear_bit(0, &is_active);
505	return 0;
506}
507
508/*
509 *	/dev/temperature handling
510 */
511
512static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
513				size_t len, loff_t *ppos)
514{
515	int temperature;
516
517	if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
518		return -EFAULT;
519
520	if (copy_to_user(data, &temperature, 1))
521		return -EFAULT;
522
523	return 1;
524}
525
526static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
527{
528	return nonseekable_open(inode, file);
529}
530
531static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
532{
533	return 0;
534}
535
536/*
537 *	Notify system
538 */
539
540static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
541								void *unused)
542{
543	if (code == SYS_DOWN || code == SYS_HALT)
544		usb_pcwd_stop(usb_pcwd_device);	/* Turn the WDT off */
545
546	return NOTIFY_DONE;
547}
548
549/*
550 *	Kernel Interfaces
551 */
552
553static const struct file_operations usb_pcwd_fops = {
554	.owner =	THIS_MODULE,
555	.llseek =	no_llseek,
556	.write =	usb_pcwd_write,
557	.unlocked_ioctl = usb_pcwd_ioctl,
558	.open =		usb_pcwd_open,
559	.release =	usb_pcwd_release,
560};
561
562static struct miscdevice usb_pcwd_miscdev = {
563	.minor =	WATCHDOG_MINOR,
564	.name =		"watchdog",
565	.fops =		&usb_pcwd_fops,
566};
567
568static const struct file_operations usb_pcwd_temperature_fops = {
569	.owner =	THIS_MODULE,
570	.llseek =	no_llseek,
571	.read =		usb_pcwd_temperature_read,
572	.open =		usb_pcwd_temperature_open,
573	.release =	usb_pcwd_temperature_release,
574};
575
576static struct miscdevice usb_pcwd_temperature_miscdev = {
577	.minor =	TEMP_MINOR,
578	.name =		"temperature",
579	.fops =		&usb_pcwd_temperature_fops,
580};
581
582static struct notifier_block usb_pcwd_notifier = {
583	.notifier_call =	usb_pcwd_notify_sys,
584};
585
586/**
587 *	usb_pcwd_delete
588 */
589static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
590{
591	usb_free_urb(usb_pcwd->intr_urb);
592	if (usb_pcwd->intr_buffer != NULL)
593		usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
594				  usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
595	kfree(usb_pcwd);
596}
597
598/**
599 *	usb_pcwd_probe
600 *
601 *	Called by the usb core when a new device is connected that it thinks
602 *	this driver might be interested in.
603 */
604static int usb_pcwd_probe(struct usb_interface *interface,
605						const struct usb_device_id *id)
606{
607	struct usb_device *udev = interface_to_usbdev(interface);
608	struct usb_host_interface *iface_desc;
609	struct usb_endpoint_descriptor *endpoint;
610	struct usb_pcwd_private *usb_pcwd = NULL;
611	int pipe, maxp;
612	int retval = -ENOMEM;
613	int got_fw_rev;
614	unsigned char fw_rev_major, fw_rev_minor;
615	char fw_ver_str[20];
616	unsigned char option_switches, dummy;
617
618	cards_found++;
619	if (cards_found > 1) {
620		pr_err("This driver only supports 1 device\n");
621		return -ENODEV;
622	}
623
624	/* get the active interface descriptor */
625	iface_desc = interface->cur_altsetting;
626
627	/* check out that we have a HID device */
628	if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
629		pr_err("The device isn't a Human Interface Device\n");
630		return -ENODEV;
631	}
632
633	/* check out the endpoint: it has to be Interrupt & IN */
634	endpoint = &iface_desc->endpoint[0].desc;
635
636	if (!usb_endpoint_is_int_in(endpoint)) {
637		/* we didn't find a Interrupt endpoint with direction IN */
638		pr_err("Couldn't find an INTR & IN endpoint\n");
639		return -ENODEV;
640	}
641
642	/* get a handle to the interrupt data pipe */
643	pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
644	maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
645
646	/* allocate memory for our device and initialize it */
647	usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
648	if (usb_pcwd == NULL)
649		goto error;
650
651	usb_pcwd_device = usb_pcwd;
652
653	mutex_init(&usb_pcwd->mtx);
654	usb_pcwd->udev = udev;
655	usb_pcwd->interface = interface;
656	usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
657	usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
658				le16_to_cpu(endpoint->wMaxPacketSize) : 8);
659
660	/* set up the memory buffer's */
661	usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size,
662					GFP_ATOMIC, &usb_pcwd->intr_dma);
663	if (!usb_pcwd->intr_buffer) {
664		pr_err("Out of memory\n");
665		goto error;
666	}
667
668	/* allocate the urb's */
669	usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
670	if (!usb_pcwd->intr_urb) {
671		pr_err("Out of memory\n");
672		goto error;
673	}
674
675	/* initialise the intr urb's */
676	usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
677			usb_pcwd->intr_buffer, usb_pcwd->intr_size,
678			usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
679	usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
680	usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
681
682	/* register our interrupt URB with the USB system */
683	if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
684		pr_err("Problem registering interrupt URB\n");
685		retval = -EIO; /* failure */
686		goto error;
687	}
688
689	/* The device exists and can be communicated with */
690	usb_pcwd->exists = 1;
691
692	/* disable card */
693	usb_pcwd_stop(usb_pcwd);
694
695	/* Get the Firmware Version */
696	got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
697						&fw_rev_major, &fw_rev_minor);
698	if (got_fw_rev)
699		sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
700	else
701		sprintf(fw_ver_str, "<card no answer>");
702
703	pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str);
704
705	/* Get switch settings */
706	usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
707							&option_switches);
708
709	pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
710		option_switches,
711		((option_switches & 0x10) ? "ON" : "OFF"),
712		((option_switches & 0x08) ? "ON" : "OFF"));
713
714	/* If heartbeat = 0 then we use the heartbeat from the dip-switches */
715	if (heartbeat == 0)
716		heartbeat = heartbeat_tbl[(option_switches & 0x07)];
717
718	/* Check that the heartbeat value is within it's range ;
719	 * if not reset to the default */
720	if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
721		usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
722		pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
723			WATCHDOG_HEARTBEAT);
724	}
725
726	retval = register_reboot_notifier(&usb_pcwd_notifier);
727	if (retval != 0) {
728		pr_err("cannot register reboot notifier (err=%d)\n", retval);
729		goto error;
730	}
731
732	retval = misc_register(&usb_pcwd_temperature_miscdev);
733	if (retval != 0) {
734		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
735		       TEMP_MINOR, retval);
736		goto err_out_unregister_reboot;
737	}
738
739	retval = misc_register(&usb_pcwd_miscdev);
740	if (retval != 0) {
741		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
742		       WATCHDOG_MINOR, retval);
743		goto err_out_misc_deregister;
744	}
745
746	/* we can register the device now, as it is ready */
747	usb_set_intfdata(interface, usb_pcwd);
748
749	pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
750		heartbeat, nowayout);
751
752	return 0;
753
754err_out_misc_deregister:
755	misc_deregister(&usb_pcwd_temperature_miscdev);
756err_out_unregister_reboot:
757	unregister_reboot_notifier(&usb_pcwd_notifier);
758error:
759	if (usb_pcwd)
760		usb_pcwd_delete(usb_pcwd);
761	usb_pcwd_device = NULL;
762	return retval;
763}
764
765
766/**
767 *	usb_pcwd_disconnect
768 *
769 *	Called by the usb core when the device is removed from the system.
770 *
771 *	This routine guarantees that the driver will not submit any more urbs
772 *	by clearing dev->udev.
773 */
774static void usb_pcwd_disconnect(struct usb_interface *interface)
775{
776	struct usb_pcwd_private *usb_pcwd;
777
778	/* prevent races with open() */
779	mutex_lock(&disconnect_mutex);
780
781	usb_pcwd = usb_get_intfdata(interface);
782	usb_set_intfdata(interface, NULL);
783
784	mutex_lock(&usb_pcwd->mtx);
785
786	/* Stop the timer before we leave */
787	if (!nowayout)
788		usb_pcwd_stop(usb_pcwd);
789
790	/* We should now stop communicating with the USB PCWD device */
791	usb_pcwd->exists = 0;
792
793	/* Deregister */
794	misc_deregister(&usb_pcwd_miscdev);
795	misc_deregister(&usb_pcwd_temperature_miscdev);
796	unregister_reboot_notifier(&usb_pcwd_notifier);
797
798	mutex_unlock(&usb_pcwd->mtx);
799
800	/* Delete the USB PCWD device */
801	usb_pcwd_delete(usb_pcwd);
802
803	cards_found--;
804
805	mutex_unlock(&disconnect_mutex);
806
807	pr_info("USB PC Watchdog disconnected\n");
808}
809
810module_usb_driver(usb_pcwd_driver);
811