xref: /openbmc/linux/drivers/watchdog/pcwd_pci.c (revision 2359ccdd)
1 /*
2  *	Berkshire PCI-PC Watchdog Card Driver
3  *
4  *	(c) Copyright 2003-2007 Wim Van Sebroeck <wim@iguana.be>.
5  *
6  *	Based on source code of the following authors:
7  *	  Ken Hollis <kenji@bitgate.com>,
8  *	  Lindsay Harris <lindsay@bluegum.com>,
9  *	  Alan Cox <alan@lxorguk.ukuu.org.uk>,
10  *	  Matt Domsch <Matt_Domsch@dell.com>,
11  *	  Rob Radez <rob@osinvestor.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 
23 /*
24  *	A bells and whistles driver is available from:
25  *	http://www.kernel.org/pub/linux/kernel/people/wim/pcwd/pcwd_pci/
26  *
27  *	More info available at
28  *	http://www.berkprod.com/ or http://www.pcwatchdog.com/
29  */
30 
31 /*
32  *	Includes, defines, variables, module parameters, ...
33  */
34 
35 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
36 
37 #include <linux/module.h>	/* For module specific items */
38 #include <linux/moduleparam.h>	/* For new moduleparam's */
39 #include <linux/types.h>	/* For standard types (like size_t) */
40 #include <linux/errno.h>	/* For the -ENODEV/... values */
41 #include <linux/kernel.h>	/* For printk/panic/... */
42 #include <linux/delay.h>	/* For mdelay function */
43 #include <linux/miscdevice.h>	/* For struct miscdevice */
44 #include <linux/watchdog.h>	/* For the watchdog specific items */
45 #include <linux/notifier.h>	/* For notifier support */
46 #include <linux/reboot.h>	/* For reboot_notifier stuff */
47 #include <linux/init.h>		/* For __init/__exit/... */
48 #include <linux/fs.h>		/* For file operations */
49 #include <linux/pci.h>		/* For pci functions */
50 #include <linux/ioport.h>	/* For io-port access */
51 #include <linux/spinlock.h>	/* For spin_lock/spin_unlock/... */
52 #include <linux/uaccess.h>	/* For copy_to_user/put_user/... */
53 #include <linux/io.h>		/* For inb/outb/... */
54 
55 /* Module and version information */
56 #define WATCHDOG_VERSION "1.03"
57 #define WATCHDOG_DRIVER_NAME "PCI-PC Watchdog"
58 #define WATCHDOG_NAME "pcwd_pci"
59 #define DRIVER_VERSION WATCHDOG_DRIVER_NAME " driver, v" WATCHDOG_VERSION
60 
61 /* Stuff for the PCI ID's  */
62 #ifndef PCI_VENDOR_ID_QUICKLOGIC
63 #define PCI_VENDOR_ID_QUICKLOGIC    0x11e3
64 #endif
65 
66 #ifndef PCI_DEVICE_ID_WATCHDOG_PCIPCWD
67 #define PCI_DEVICE_ID_WATCHDOG_PCIPCWD 0x5030
68 #endif
69 
70 /*
71  * These are the defines that describe the control status bits for the
72  * PCI-PC Watchdog card.
73  */
74 /* Port 1 : Control Status #1 */
75 #define WD_PCI_WTRP		0x01	/* Watchdog Trip status */
76 #define WD_PCI_HRBT		0x02	/* Watchdog Heartbeat */
77 #define WD_PCI_TTRP		0x04	/* Temperature Trip status */
78 #define WD_PCI_RL2A		0x08	/* Relay 2 Active */
79 #define WD_PCI_RL1A		0x10	/* Relay 1 Active */
80 #define WD_PCI_R2DS		0x40	/* Relay 2 Disable Temperature-trip /
81 									reset */
82 #define WD_PCI_RLY2		0x80	/* Activate Relay 2 on the board */
83 /* Port 2 : Control Status #2 */
84 #define WD_PCI_WDIS		0x10	/* Watchdog Disable */
85 #define WD_PCI_ENTP		0x20	/* Enable Temperature Trip Reset */
86 #define WD_PCI_WRSP		0x40	/* Watchdog wrote response */
87 #define WD_PCI_PCMD		0x80	/* PC has sent command */
88 
89 /* according to documentation max. time to process a command for the pci
90  * watchdog card is 100 ms, so we give it 150 ms to do it's job */
91 #define PCI_COMMAND_TIMEOUT	150
92 
93 /* Watchdog's internal commands */
94 #define CMD_GET_STATUS				0x04
95 #define CMD_GET_FIRMWARE_VERSION		0x08
96 #define CMD_READ_WATCHDOG_TIMEOUT		0x18
97 #define CMD_WRITE_WATCHDOG_TIMEOUT		0x19
98 #define CMD_GET_CLEAR_RESET_COUNT		0x84
99 
100 /* Watchdog's Dip Switch heartbeat values */
101 static const int heartbeat_tbl[] = {
102 	5,	/* OFF-OFF-OFF	=  5 Sec  */
103 	10,	/* OFF-OFF-ON	= 10 Sec  */
104 	30,	/* OFF-ON-OFF	= 30 Sec  */
105 	60,	/* OFF-ON-ON	=  1 Min  */
106 	300,	/* ON-OFF-OFF	=  5 Min  */
107 	600,	/* ON-OFF-ON	= 10 Min  */
108 	1800,	/* ON-ON-OFF	= 30 Min  */
109 	3600,	/* ON-ON-ON	=  1 hour */
110 };
111 
112 /* We can only use 1 card due to the /dev/watchdog restriction */
113 static int cards_found;
114 
115 /* internal variables */
116 static int temp_panic;
117 static unsigned long is_active;
118 static char expect_release;
119 /* this is private data for each PCI-PC watchdog card */
120 static struct {
121 	/* Wether or not the card has a temperature device */
122 	int supports_temp;
123 	/* The card's boot status */
124 	int boot_status;
125 	/* The cards I/O address */
126 	unsigned long io_addr;
127 	/* the lock for io operations */
128 	spinlock_t io_lock;
129 	/* the PCI-device */
130 	struct pci_dev *pdev;
131 } pcipcwd_private;
132 
133 /* module parameters */
134 #define QUIET	0	/* Default */
135 #define VERBOSE	1	/* Verbose */
136 #define DEBUG	2	/* print fancy stuff too */
137 static int debug = QUIET;
138 module_param(debug, int, 0);
139 MODULE_PARM_DESC(debug, "Debug level: 0=Quiet, 1=Verbose, 2=Debug (default=0)");
140 
141 #define WATCHDOG_HEARTBEAT 0	/* default heartbeat =
142 						delay-time from dip-switches */
143 static int heartbeat = WATCHDOG_HEARTBEAT;
144 module_param(heartbeat, int, 0);
145 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
146 	"(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
147 				__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
148 
149 static bool nowayout = WATCHDOG_NOWAYOUT;
150 module_param(nowayout, bool, 0);
151 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
152 					__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
153 
154 /*
155  *	Internal functions
156  */
157 
158 static int send_command(int cmd, int *msb, int *lsb)
159 {
160 	int got_response, count;
161 
162 	if (debug >= DEBUG)
163 		pr_debug("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x\n",
164 			 cmd, *msb, *lsb);
165 
166 	spin_lock(&pcipcwd_private.io_lock);
167 	/* If a command requires data it should be written first.
168 	 * Data for commands with 8 bits of data should be written to port 4.
169 	 * Commands with 16 bits of data, should be written as LSB to port 4
170 	 * and MSB to port 5.
171 	 * After the required data has been written then write the command to
172 	 * port 6. */
173 	outb_p(*lsb, pcipcwd_private.io_addr + 4);
174 	outb_p(*msb, pcipcwd_private.io_addr + 5);
175 	outb_p(cmd, pcipcwd_private.io_addr + 6);
176 
177 	/* wait till the pci card processed the command, signaled by
178 	 * the WRSP bit in port 2 and give it a max. timeout of
179 	 * PCI_COMMAND_TIMEOUT to process */
180 	got_response = inb_p(pcipcwd_private.io_addr + 2) & WD_PCI_WRSP;
181 	for (count = 0; (count < PCI_COMMAND_TIMEOUT) && (!got_response);
182 								count++) {
183 		mdelay(1);
184 		got_response = inb_p(pcipcwd_private.io_addr + 2) & WD_PCI_WRSP;
185 	}
186 
187 	if (debug >= DEBUG) {
188 		if (got_response) {
189 			pr_debug("time to process command was: %d ms\n",
190 				 count);
191 		} else {
192 			pr_debug("card did not respond on command!\n");
193 		}
194 	}
195 
196 	if (got_response) {
197 		/* read back response */
198 		*lsb = inb_p(pcipcwd_private.io_addr + 4);
199 		*msb = inb_p(pcipcwd_private.io_addr + 5);
200 
201 		/* clear WRSP bit */
202 		inb_p(pcipcwd_private.io_addr + 6);
203 
204 		if (debug >= DEBUG)
205 			pr_debug("received following data for cmd=0x%02x: msb=0x%02x lsb=0x%02x\n",
206 				 cmd, *msb, *lsb);
207 	}
208 
209 	spin_unlock(&pcipcwd_private.io_lock);
210 
211 	return got_response;
212 }
213 
214 static inline void pcipcwd_check_temperature_support(void)
215 {
216 	if (inb_p(pcipcwd_private.io_addr) != 0xF0)
217 		pcipcwd_private.supports_temp = 1;
218 }
219 
220 static int pcipcwd_get_option_switches(void)
221 {
222 	int option_switches;
223 
224 	option_switches = inb_p(pcipcwd_private.io_addr + 3);
225 	return option_switches;
226 }
227 
228 static void pcipcwd_show_card_info(void)
229 {
230 	int got_fw_rev, fw_rev_major, fw_rev_minor;
231 	char fw_ver_str[20];		/* The cards firmware version */
232 	int option_switches;
233 
234 	got_fw_rev = send_command(CMD_GET_FIRMWARE_VERSION, &fw_rev_major,
235 								&fw_rev_minor);
236 	if (got_fw_rev)
237 		sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
238 	else
239 		sprintf(fw_ver_str, "<card no answer>");
240 
241 	/* Get switch settings */
242 	option_switches = pcipcwd_get_option_switches();
243 
244 	pr_info("Found card at port 0x%04x (Firmware: %s) %s temp option\n",
245 		(int) pcipcwd_private.io_addr, fw_ver_str,
246 		(pcipcwd_private.supports_temp ? "with" : "without"));
247 
248 	pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
249 		option_switches,
250 		((option_switches & 0x10) ? "ON" : "OFF"),
251 		((option_switches & 0x08) ? "ON" : "OFF"));
252 
253 	if (pcipcwd_private.boot_status & WDIOF_CARDRESET)
254 		pr_info("Previous reset was caused by the Watchdog card\n");
255 
256 	if (pcipcwd_private.boot_status & WDIOF_OVERHEAT)
257 		pr_info("Card sensed a CPU Overheat\n");
258 
259 	if (pcipcwd_private.boot_status == 0)
260 		pr_info("No previous trip detected - Cold boot or reset\n");
261 }
262 
263 static int pcipcwd_start(void)
264 {
265 	int stat_reg;
266 
267 	spin_lock(&pcipcwd_private.io_lock);
268 	outb_p(0x00, pcipcwd_private.io_addr + 3);
269 	udelay(1000);
270 
271 	stat_reg = inb_p(pcipcwd_private.io_addr + 2);
272 	spin_unlock(&pcipcwd_private.io_lock);
273 
274 	if (stat_reg & WD_PCI_WDIS) {
275 		pr_err("Card timer not enabled\n");
276 		return -1;
277 	}
278 
279 	if (debug >= VERBOSE)
280 		pr_debug("Watchdog started\n");
281 
282 	return 0;
283 }
284 
285 static int pcipcwd_stop(void)
286 {
287 	int stat_reg;
288 
289 	spin_lock(&pcipcwd_private.io_lock);
290 	outb_p(0xA5, pcipcwd_private.io_addr + 3);
291 	udelay(1000);
292 
293 	outb_p(0xA5, pcipcwd_private.io_addr + 3);
294 	udelay(1000);
295 
296 	stat_reg = inb_p(pcipcwd_private.io_addr + 2);
297 	spin_unlock(&pcipcwd_private.io_lock);
298 
299 	if (!(stat_reg & WD_PCI_WDIS)) {
300 		pr_err("Card did not acknowledge disable attempt\n");
301 		return -1;
302 	}
303 
304 	if (debug >= VERBOSE)
305 		pr_debug("Watchdog stopped\n");
306 
307 	return 0;
308 }
309 
310 static int pcipcwd_keepalive(void)
311 {
312 	/* Re-trigger watchdog by writing to port 0 */
313 	spin_lock(&pcipcwd_private.io_lock);
314 	outb_p(0x42, pcipcwd_private.io_addr);	/* send out any data */
315 	spin_unlock(&pcipcwd_private.io_lock);
316 
317 	if (debug >= DEBUG)
318 		pr_debug("Watchdog keepalive signal send\n");
319 
320 	return 0;
321 }
322 
323 static int pcipcwd_set_heartbeat(int t)
324 {
325 	int t_msb = t / 256;
326 	int t_lsb = t % 256;
327 
328 	if ((t < 0x0001) || (t > 0xFFFF))
329 		return -EINVAL;
330 
331 	/* Write new heartbeat to watchdog */
332 	send_command(CMD_WRITE_WATCHDOG_TIMEOUT, &t_msb, &t_lsb);
333 
334 	heartbeat = t;
335 	if (debug >= VERBOSE)
336 		pr_debug("New heartbeat: %d\n", heartbeat);
337 
338 	return 0;
339 }
340 
341 static int pcipcwd_get_status(int *status)
342 {
343 	int control_status;
344 
345 	*status = 0;
346 	control_status = inb_p(pcipcwd_private.io_addr + 1);
347 	if (control_status & WD_PCI_WTRP)
348 		*status |= WDIOF_CARDRESET;
349 	if (control_status & WD_PCI_TTRP) {
350 		*status |= WDIOF_OVERHEAT;
351 		if (temp_panic)
352 			panic(KBUILD_MODNAME ": Temperature overheat trip!\n");
353 	}
354 
355 	if (debug >= DEBUG)
356 		pr_debug("Control Status #1: 0x%02x\n", control_status);
357 
358 	return 0;
359 }
360 
361 static int pcipcwd_clear_status(void)
362 {
363 	int control_status;
364 	int msb;
365 	int reset_counter;
366 
367 	if (debug >= VERBOSE)
368 		pr_info("clearing watchdog trip status & LED\n");
369 
370 	control_status = inb_p(pcipcwd_private.io_addr + 1);
371 
372 	if (debug >= DEBUG) {
373 		pr_debug("status was: 0x%02x\n", control_status);
374 		pr_debug("sending: 0x%02x\n",
375 			 (control_status & WD_PCI_R2DS) | WD_PCI_WTRP);
376 	}
377 
378 	/* clear trip status & LED and keep mode of relay 2 */
379 	outb_p((control_status & WD_PCI_R2DS) | WD_PCI_WTRP,
380 						pcipcwd_private.io_addr + 1);
381 
382 	/* clear reset counter */
383 	msb = 0;
384 	reset_counter = 0xff;
385 	send_command(CMD_GET_CLEAR_RESET_COUNT, &msb, &reset_counter);
386 
387 	if (debug >= DEBUG) {
388 		pr_debug("reset count was: 0x%02x\n", reset_counter);
389 	}
390 
391 	return 0;
392 }
393 
394 static int pcipcwd_get_temperature(int *temperature)
395 {
396 	*temperature = 0;
397 	if (!pcipcwd_private.supports_temp)
398 		return -ENODEV;
399 
400 	spin_lock(&pcipcwd_private.io_lock);
401 	*temperature = inb_p(pcipcwd_private.io_addr);
402 	spin_unlock(&pcipcwd_private.io_lock);
403 
404 	/*
405 	 * Convert celsius to fahrenheit, since this was
406 	 * the decided 'standard' for this return value.
407 	 */
408 	*temperature = (*temperature * 9 / 5) + 32;
409 
410 	if (debug >= DEBUG) {
411 		pr_debug("temperature is: %d F\n", *temperature);
412 	}
413 
414 	return 0;
415 }
416 
417 static int pcipcwd_get_timeleft(int *time_left)
418 {
419 	int msb;
420 	int lsb;
421 
422 	/* Read the time that's left before rebooting */
423 	/* Note: if the board is not yet armed then we will read 0xFFFF */
424 	send_command(CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
425 
426 	*time_left = (msb << 8) + lsb;
427 
428 	if (debug >= VERBOSE)
429 		pr_debug("Time left before next reboot: %d\n", *time_left);
430 
431 	return 0;
432 }
433 
434 /*
435  *	/dev/watchdog handling
436  */
437 
438 static ssize_t pcipcwd_write(struct file *file, const char __user *data,
439 			     size_t len, loff_t *ppos)
440 {
441 	/* See if we got the magic character 'V' and reload the timer */
442 	if (len) {
443 		if (!nowayout) {
444 			size_t i;
445 
446 			/* note: just in case someone wrote the magic character
447 			 * five months ago... */
448 			expect_release = 0;
449 
450 			/* scan to see whether or not we got the
451 			 * magic character */
452 			for (i = 0; i != len; i++) {
453 				char c;
454 				if (get_user(c, data + i))
455 					return -EFAULT;
456 				if (c == 'V')
457 					expect_release = 42;
458 			}
459 		}
460 
461 		/* someone wrote to us, we should reload the timer */
462 		pcipcwd_keepalive();
463 	}
464 	return len;
465 }
466 
467 static long pcipcwd_ioctl(struct file *file, unsigned int cmd,
468 						unsigned long arg)
469 {
470 	void __user *argp = (void __user *)arg;
471 	int __user *p = argp;
472 	static const struct watchdog_info ident = {
473 		.options =		WDIOF_OVERHEAT |
474 					WDIOF_CARDRESET |
475 					WDIOF_KEEPALIVEPING |
476 					WDIOF_SETTIMEOUT |
477 					WDIOF_MAGICCLOSE,
478 		.firmware_version =	1,
479 		.identity =		WATCHDOG_DRIVER_NAME,
480 	};
481 
482 	switch (cmd) {
483 	case WDIOC_GETSUPPORT:
484 		return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
485 
486 	case WDIOC_GETSTATUS:
487 	{
488 		int status;
489 		pcipcwd_get_status(&status);
490 		return put_user(status, p);
491 	}
492 
493 	case WDIOC_GETBOOTSTATUS:
494 		return put_user(pcipcwd_private.boot_status, p);
495 
496 	case WDIOC_GETTEMP:
497 	{
498 		int temperature;
499 
500 		if (pcipcwd_get_temperature(&temperature))
501 			return -EFAULT;
502 
503 		return put_user(temperature, p);
504 	}
505 
506 	case WDIOC_SETOPTIONS:
507 	{
508 		int new_options, retval = -EINVAL;
509 
510 		if (get_user(new_options, p))
511 			return -EFAULT;
512 
513 		if (new_options & WDIOS_DISABLECARD) {
514 			if (pcipcwd_stop())
515 				return -EIO;
516 			retval = 0;
517 		}
518 
519 		if (new_options & WDIOS_ENABLECARD) {
520 			if (pcipcwd_start())
521 				return -EIO;
522 			retval = 0;
523 		}
524 
525 		if (new_options & WDIOS_TEMPPANIC) {
526 			temp_panic = 1;
527 			retval = 0;
528 		}
529 
530 		return retval;
531 	}
532 
533 	case WDIOC_KEEPALIVE:
534 		pcipcwd_keepalive();
535 		return 0;
536 
537 	case WDIOC_SETTIMEOUT:
538 	{
539 		int new_heartbeat;
540 
541 		if (get_user(new_heartbeat, p))
542 			return -EFAULT;
543 
544 		if (pcipcwd_set_heartbeat(new_heartbeat))
545 			return -EINVAL;
546 
547 		pcipcwd_keepalive();
548 	}
549 		/* fall through */
550 
551 	case WDIOC_GETTIMEOUT:
552 		return put_user(heartbeat, p);
553 
554 	case WDIOC_GETTIMELEFT:
555 	{
556 		int time_left;
557 
558 		if (pcipcwd_get_timeleft(&time_left))
559 			return -EFAULT;
560 
561 		return put_user(time_left, p);
562 	}
563 
564 	default:
565 		return -ENOTTY;
566 	}
567 }
568 
569 static int pcipcwd_open(struct inode *inode, struct file *file)
570 {
571 	/* /dev/watchdog can only be opened once */
572 	if (test_and_set_bit(0, &is_active)) {
573 		if (debug >= VERBOSE)
574 			pr_err("Attempt to open already opened device\n");
575 		return -EBUSY;
576 	}
577 
578 	/* Activate */
579 	pcipcwd_start();
580 	pcipcwd_keepalive();
581 	return nonseekable_open(inode, file);
582 }
583 
584 static int pcipcwd_release(struct inode *inode, struct file *file)
585 {
586 	/*
587 	 *      Shut off the timer.
588 	 */
589 	if (expect_release == 42) {
590 		pcipcwd_stop();
591 	} else {
592 		pr_crit("Unexpected close, not stopping watchdog!\n");
593 		pcipcwd_keepalive();
594 	}
595 	expect_release = 0;
596 	clear_bit(0, &is_active);
597 	return 0;
598 }
599 
600 /*
601  *	/dev/temperature handling
602  */
603 
604 static ssize_t pcipcwd_temp_read(struct file *file, char __user *data,
605 				size_t len, loff_t *ppos)
606 {
607 	int temperature;
608 
609 	if (pcipcwd_get_temperature(&temperature))
610 		return -EFAULT;
611 
612 	if (copy_to_user(data, &temperature, 1))
613 		return -EFAULT;
614 
615 	return 1;
616 }
617 
618 static int pcipcwd_temp_open(struct inode *inode, struct file *file)
619 {
620 	if (!pcipcwd_private.supports_temp)
621 		return -ENODEV;
622 
623 	return nonseekable_open(inode, file);
624 }
625 
626 static int pcipcwd_temp_release(struct inode *inode, struct file *file)
627 {
628 	return 0;
629 }
630 
631 /*
632  *	Notify system
633  */
634 
635 static int pcipcwd_notify_sys(struct notifier_block *this, unsigned long code,
636 								void *unused)
637 {
638 	if (code == SYS_DOWN || code == SYS_HALT)
639 		pcipcwd_stop();	/* Turn the WDT off */
640 
641 	return NOTIFY_DONE;
642 }
643 
644 /*
645  *	Kernel Interfaces
646  */
647 
648 static const struct file_operations pcipcwd_fops = {
649 	.owner =	THIS_MODULE,
650 	.llseek =	no_llseek,
651 	.write =	pcipcwd_write,
652 	.unlocked_ioctl = pcipcwd_ioctl,
653 	.open =		pcipcwd_open,
654 	.release =	pcipcwd_release,
655 };
656 
657 static struct miscdevice pcipcwd_miscdev = {
658 	.minor =	WATCHDOG_MINOR,
659 	.name =		"watchdog",
660 	.fops =		&pcipcwd_fops,
661 };
662 
663 static const struct file_operations pcipcwd_temp_fops = {
664 	.owner =	THIS_MODULE,
665 	.llseek =	no_llseek,
666 	.read =		pcipcwd_temp_read,
667 	.open =		pcipcwd_temp_open,
668 	.release =	pcipcwd_temp_release,
669 };
670 
671 static struct miscdevice pcipcwd_temp_miscdev = {
672 	.minor =	TEMP_MINOR,
673 	.name =		"temperature",
674 	.fops =		&pcipcwd_temp_fops,
675 };
676 
677 static struct notifier_block pcipcwd_notifier = {
678 	.notifier_call =	pcipcwd_notify_sys,
679 };
680 
681 /*
682  *	Init & exit routines
683  */
684 
685 static int pcipcwd_card_init(struct pci_dev *pdev,
686 		const struct pci_device_id *ent)
687 {
688 	int ret = -EIO;
689 
690 	cards_found++;
691 	if (cards_found == 1)
692 		pr_info("%s\n", DRIVER_VERSION);
693 
694 	if (cards_found > 1) {
695 		pr_err("This driver only supports 1 device\n");
696 		return -ENODEV;
697 	}
698 
699 	if (pci_enable_device(pdev)) {
700 		pr_err("Not possible to enable PCI Device\n");
701 		return -ENODEV;
702 	}
703 
704 	if (pci_resource_start(pdev, 0) == 0x0000) {
705 		pr_err("No I/O-Address for card detected\n");
706 		ret = -ENODEV;
707 		goto err_out_disable_device;
708 	}
709 
710 	spin_lock_init(&pcipcwd_private.io_lock);
711 	pcipcwd_private.pdev = pdev;
712 	pcipcwd_private.io_addr = pci_resource_start(pdev, 0);
713 
714 	if (pci_request_regions(pdev, WATCHDOG_NAME)) {
715 		pr_err("I/O address 0x%04x already in use\n",
716 		       (int) pcipcwd_private.io_addr);
717 		ret = -EIO;
718 		goto err_out_disable_device;
719 	}
720 
721 	/* get the boot_status */
722 	pcipcwd_get_status(&pcipcwd_private.boot_status);
723 
724 	/* clear the "card caused reboot" flag */
725 	pcipcwd_clear_status();
726 
727 	/* disable card */
728 	pcipcwd_stop();
729 
730 	/* Check whether or not the card supports the temperature device */
731 	pcipcwd_check_temperature_support();
732 
733 	/* Show info about the card itself */
734 	pcipcwd_show_card_info();
735 
736 	/* If heartbeat = 0 then we use the heartbeat from the dip-switches */
737 	if (heartbeat == 0)
738 		heartbeat =
739 			heartbeat_tbl[(pcipcwd_get_option_switches() & 0x07)];
740 
741 	/* Check that the heartbeat value is within it's range ;
742 	 * if not reset to the default */
743 	if (pcipcwd_set_heartbeat(heartbeat)) {
744 		pcipcwd_set_heartbeat(WATCHDOG_HEARTBEAT);
745 		pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
746 			WATCHDOG_HEARTBEAT);
747 	}
748 
749 	ret = register_reboot_notifier(&pcipcwd_notifier);
750 	if (ret != 0) {
751 		pr_err("cannot register reboot notifier (err=%d)\n", ret);
752 		goto err_out_release_region;
753 	}
754 
755 	if (pcipcwd_private.supports_temp) {
756 		ret = misc_register(&pcipcwd_temp_miscdev);
757 		if (ret != 0) {
758 			pr_err("cannot register miscdev on minor=%d (err=%d)\n",
759 			       TEMP_MINOR, ret);
760 			goto err_out_unregister_reboot;
761 		}
762 	}
763 
764 	ret = misc_register(&pcipcwd_miscdev);
765 	if (ret != 0) {
766 		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
767 		       WATCHDOG_MINOR, ret);
768 		goto err_out_misc_deregister;
769 	}
770 
771 	pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
772 		heartbeat, nowayout);
773 
774 	return 0;
775 
776 err_out_misc_deregister:
777 	if (pcipcwd_private.supports_temp)
778 		misc_deregister(&pcipcwd_temp_miscdev);
779 err_out_unregister_reboot:
780 	unregister_reboot_notifier(&pcipcwd_notifier);
781 err_out_release_region:
782 	pci_release_regions(pdev);
783 err_out_disable_device:
784 	pci_disable_device(pdev);
785 	return ret;
786 }
787 
788 static void pcipcwd_card_exit(struct pci_dev *pdev)
789 {
790 	/* Stop the timer before we leave */
791 	if (!nowayout)
792 		pcipcwd_stop();
793 
794 	/* Deregister */
795 	misc_deregister(&pcipcwd_miscdev);
796 	if (pcipcwd_private.supports_temp)
797 		misc_deregister(&pcipcwd_temp_miscdev);
798 	unregister_reboot_notifier(&pcipcwd_notifier);
799 	pci_release_regions(pdev);
800 	pci_disable_device(pdev);
801 	cards_found--;
802 }
803 
804 static const struct pci_device_id pcipcwd_pci_tbl[] = {
805 	{ PCI_VENDOR_ID_QUICKLOGIC, PCI_DEVICE_ID_WATCHDOG_PCIPCWD,
806 		PCI_ANY_ID, PCI_ANY_ID, },
807 	{ 0 },			/* End of list */
808 };
809 MODULE_DEVICE_TABLE(pci, pcipcwd_pci_tbl);
810 
811 static struct pci_driver pcipcwd_driver = {
812 	.name		= WATCHDOG_NAME,
813 	.id_table	= pcipcwd_pci_tbl,
814 	.probe		= pcipcwd_card_init,
815 	.remove		= pcipcwd_card_exit,
816 };
817 
818 module_pci_driver(pcipcwd_driver);
819 
820 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
821 MODULE_DESCRIPTION("Berkshire PCI-PC Watchdog driver");
822 MODULE_LICENSE("GPL");
823