1 /* 2 * Industrial Computer Source PCI-WDT500/501 driver 3 * 4 * (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>, 5 * All Rights Reserved. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 * 12 * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide 13 * warranty for any of this software. This material is provided 14 * "AS-IS" and at no charge. 15 * 16 * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk> 17 * 18 * Release 0.10. 19 * 20 * Fixes 21 * Dave Gregorich : Modularisation and minor bugs 22 * Alan Cox : Added the watchdog ioctl() stuff 23 * Alan Cox : Fixed the reboot problem (as noted by 24 * Matt Crocker). 25 * Alan Cox : Added wdt= boot option 26 * Alan Cox : Cleaned up copy/user stuff 27 * Tim Hockin : Added insmod parameters, comment cleanup 28 * Parameterized timeout 29 * JP Nollmann : Added support for PCI wdt501p 30 * Alan Cox : Split ISA and PCI cards into two drivers 31 * Jeff Garzik : PCI cleanups 32 * Tigran Aivazian : Restructured wdtpci_init_one() to handle 33 * failures 34 * Joel Becker : Added WDIOC_GET/SETTIMEOUT 35 * Zwane Mwaikambo : Magic char closing, locking changes, 36 * cleanups 37 * Matt Domsch : nowayout module option 38 */ 39 40 #include <linux/interrupt.h> 41 #include <linux/module.h> 42 #include <linux/moduleparam.h> 43 #include <linux/types.h> 44 #include <linux/miscdevice.h> 45 #include <linux/watchdog.h> 46 #include <linux/ioport.h> 47 #include <linux/delay.h> 48 #include <linux/notifier.h> 49 #include <linux/reboot.h> 50 #include <linux/init.h> 51 #include <linux/fs.h> 52 #include <linux/pci.h> 53 #include <linux/io.h> 54 #include <linux/uaccess.h> 55 56 #include <asm/system.h> 57 58 #define WDT_IS_PCI 59 #include "wd501p.h" 60 61 #define PFX "wdt_pci: " 62 63 /* We can only use 1 card due to the /dev/watchdog restriction */ 64 static int dev_count; 65 66 static unsigned long open_lock; 67 static DEFINE_SPINLOCK(wdtpci_lock); 68 static char expect_close; 69 70 static resource_size_t io; 71 static int irq; 72 73 /* Default timeout */ 74 #define WD_TIMO 60 /* Default heartbeat = 60 seconds */ 75 76 static int heartbeat = WD_TIMO; 77 static int wd_heartbeat; 78 module_param(heartbeat, int, 0); 79 MODULE_PARM_DESC(heartbeat, 80 "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" 81 __MODULE_STRING(WD_TIMO) ")"); 82 83 static int nowayout = WATCHDOG_NOWAYOUT; 84 module_param(nowayout, int, 0); 85 MODULE_PARM_DESC(nowayout, 86 "Watchdog cannot be stopped once started (default=" 87 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 88 89 /* Support for the Fan Tachometer on the PCI-WDT501 */ 90 static int tachometer; 91 module_param(tachometer, int, 0); 92 MODULE_PARM_DESC(tachometer, 93 "PCI-WDT501 Fan Tachometer support (0=disable, default=0)"); 94 95 static int type = 500; 96 module_param(type, int, 0); 97 MODULE_PARM_DESC(type, 98 "PCI-WDT501 Card type (500 or 501 , default=500)"); 99 100 /* 101 * Programming support 102 */ 103 104 static void wdtpci_ctr_mode(int ctr, int mode) 105 { 106 ctr <<= 6; 107 ctr |= 0x30; 108 ctr |= (mode << 1); 109 outb(ctr, WDT_CR); 110 udelay(8); 111 } 112 113 static void wdtpci_ctr_load(int ctr, int val) 114 { 115 outb(val & 0xFF, WDT_COUNT0 + ctr); 116 udelay(8); 117 outb(val >> 8, WDT_COUNT0 + ctr); 118 udelay(8); 119 } 120 121 /** 122 * wdtpci_start: 123 * 124 * Start the watchdog driver. 125 */ 126 127 static int wdtpci_start(void) 128 { 129 unsigned long flags; 130 131 spin_lock_irqsave(&wdtpci_lock, flags); 132 133 /* 134 * "pet" the watchdog, as Access says. 135 * This resets the clock outputs. 136 */ 137 inb(WDT_DC); /* Disable watchdog */ 138 udelay(8); 139 wdtpci_ctr_mode(2, 0); /* Program CTR2 for Mode 0: 140 Pulse on Terminal Count */ 141 outb(0, WDT_DC); /* Enable watchdog */ 142 udelay(8); 143 inb(WDT_DC); /* Disable watchdog */ 144 udelay(8); 145 outb(0, WDT_CLOCK); /* 2.0833MHz clock */ 146 udelay(8); 147 inb(WDT_BUZZER); /* disable */ 148 udelay(8); 149 inb(WDT_OPTONOTRST); /* disable */ 150 udelay(8); 151 inb(WDT_OPTORST); /* disable */ 152 udelay(8); 153 inb(WDT_PROGOUT); /* disable */ 154 udelay(8); 155 wdtpci_ctr_mode(0, 3); /* Program CTR0 for Mode 3: 156 Square Wave Generator */ 157 wdtpci_ctr_mode(1, 2); /* Program CTR1 for Mode 2: 158 Rate Generator */ 159 wdtpci_ctr_mode(2, 1); /* Program CTR2 for Mode 1: 160 Retriggerable One-Shot */ 161 wdtpci_ctr_load(0, 20833); /* count at 100Hz */ 162 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */ 163 /* DO NOT LOAD CTR2 on PCI card! -- JPN */ 164 outb(0, WDT_DC); /* Enable watchdog */ 165 udelay(8); 166 167 spin_unlock_irqrestore(&wdtpci_lock, flags); 168 return 0; 169 } 170 171 /** 172 * wdtpci_stop: 173 * 174 * Stop the watchdog driver. 175 */ 176 177 static int wdtpci_stop(void) 178 { 179 unsigned long flags; 180 181 /* Turn the card off */ 182 spin_lock_irqsave(&wdtpci_lock, flags); 183 inb(WDT_DC); /* Disable watchdog */ 184 udelay(8); 185 wdtpci_ctr_load(2, 0); /* 0 length reset pulses now */ 186 spin_unlock_irqrestore(&wdtpci_lock, flags); 187 return 0; 188 } 189 190 /** 191 * wdtpci_ping: 192 * 193 * Reload counter one with the watchdog heartbeat. We don't bother 194 * reloading the cascade counter. 195 */ 196 197 static int wdtpci_ping(void) 198 { 199 unsigned long flags; 200 201 spin_lock_irqsave(&wdtpci_lock, flags); 202 /* Write a watchdog value */ 203 inb(WDT_DC); /* Disable watchdog */ 204 udelay(8); 205 wdtpci_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2: 206 Rate Generator */ 207 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */ 208 outb(0, WDT_DC); /* Enable watchdog */ 209 udelay(8); 210 spin_unlock_irqrestore(&wdtpci_lock, flags); 211 return 0; 212 } 213 214 /** 215 * wdtpci_set_heartbeat: 216 * @t: the new heartbeat value that needs to be set. 217 * 218 * Set a new heartbeat value for the watchdog device. If the heartbeat 219 * value is incorrect we keep the old value and return -EINVAL. 220 * If successful we return 0. 221 */ 222 static int wdtpci_set_heartbeat(int t) 223 { 224 /* Arbitrary, can't find the card's limits */ 225 if (t < 1 || t > 65535) 226 return -EINVAL; 227 228 heartbeat = t; 229 wd_heartbeat = t * 100; 230 return 0; 231 } 232 233 /** 234 * wdtpci_get_status: 235 * @status: the new status. 236 * 237 * Extract the status information from a WDT watchdog device. There are 238 * several board variants so we have to know which bits are valid. Some 239 * bits default to one and some to zero in order to be maximally painful. 240 * 241 * we then map the bits onto the status ioctl flags. 242 */ 243 244 static int wdtpci_get_status(int *status) 245 { 246 unsigned char new_status; 247 unsigned long flags; 248 249 spin_lock_irqsave(&wdtpci_lock, flags); 250 new_status = inb(WDT_SR); 251 spin_unlock_irqrestore(&wdtpci_lock, flags); 252 253 *status = 0; 254 if (new_status & WDC_SR_ISOI0) 255 *status |= WDIOF_EXTERN1; 256 if (new_status & WDC_SR_ISII1) 257 *status |= WDIOF_EXTERN2; 258 if (type == 501) { 259 if (!(new_status & WDC_SR_TGOOD)) 260 *status |= WDIOF_OVERHEAT; 261 if (!(new_status & WDC_SR_PSUOVER)) 262 *status |= WDIOF_POWEROVER; 263 if (!(new_status & WDC_SR_PSUUNDR)) 264 *status |= WDIOF_POWERUNDER; 265 if (tachometer) { 266 if (!(new_status & WDC_SR_FANGOOD)) 267 *status |= WDIOF_FANFAULT; 268 } 269 } 270 return 0; 271 } 272 273 /** 274 * wdtpci_get_temperature: 275 * 276 * Reports the temperature in degrees Fahrenheit. The API is in 277 * farenheit. It was designed by an imperial measurement luddite. 278 */ 279 280 static int wdtpci_get_temperature(int *temperature) 281 { 282 unsigned short c; 283 unsigned long flags; 284 spin_lock_irqsave(&wdtpci_lock, flags); 285 c = inb(WDT_RT); 286 udelay(8); 287 spin_unlock_irqrestore(&wdtpci_lock, flags); 288 *temperature = (c * 11 / 15) + 7; 289 return 0; 290 } 291 292 /** 293 * wdtpci_interrupt: 294 * @irq: Interrupt number 295 * @dev_id: Unused as we don't allow multiple devices. 296 * 297 * Handle an interrupt from the board. These are raised when the status 298 * map changes in what the board considers an interesting way. That means 299 * a failure condition occurring. 300 */ 301 302 static irqreturn_t wdtpci_interrupt(int irq, void *dev_id) 303 { 304 /* 305 * Read the status register see what is up and 306 * then printk it. 307 */ 308 unsigned char status; 309 310 spin_lock(&wdtpci_lock); 311 312 status = inb(WDT_SR); 313 udelay(8); 314 315 printk(KERN_CRIT PFX "status %d\n", status); 316 317 if (type == 501) { 318 if (!(status & WDC_SR_TGOOD)) { 319 printk(KERN_CRIT PFX "Overheat alarm.(%d)\n", 320 inb(WDT_RT)); 321 udelay(8); 322 } 323 if (!(status & WDC_SR_PSUOVER)) 324 printk(KERN_CRIT PFX "PSU over voltage.\n"); 325 if (!(status & WDC_SR_PSUUNDR)) 326 printk(KERN_CRIT PFX "PSU under voltage.\n"); 327 if (tachometer) { 328 if (!(status & WDC_SR_FANGOOD)) 329 printk(KERN_CRIT PFX "Possible fan fault.\n"); 330 } 331 } 332 if (!(status & WDC_SR_WCCR)) { 333 #ifdef SOFTWARE_REBOOT 334 #ifdef ONLY_TESTING 335 printk(KERN_CRIT PFX "Would Reboot.\n"); 336 #else 337 printk(KERN_CRIT PFX "Initiating system reboot.\n"); 338 emergency_restart(NULL); 339 #endif 340 #else 341 printk(KERN_CRIT PFX "Reset in 5ms.\n"); 342 #endif 343 } 344 spin_unlock(&wdtpci_lock); 345 return IRQ_HANDLED; 346 } 347 348 349 /** 350 * wdtpci_write: 351 * @file: file handle to the watchdog 352 * @buf: buffer to write (unused as data does not matter here 353 * @count: count of bytes 354 * @ppos: pointer to the position to write. No seeks allowed 355 * 356 * A write to a watchdog device is defined as a keepalive signal. Any 357 * write of data will do, as we we don't define content meaning. 358 */ 359 360 static ssize_t wdtpci_write(struct file *file, const char __user *buf, 361 size_t count, loff_t *ppos) 362 { 363 if (count) { 364 if (!nowayout) { 365 size_t i; 366 367 /* In case it was set long ago */ 368 expect_close = 0; 369 370 for (i = 0; i != count; i++) { 371 char c; 372 if (get_user(c, buf + i)) 373 return -EFAULT; 374 if (c == 'V') 375 expect_close = 42; 376 } 377 } 378 wdtpci_ping(); 379 } 380 return count; 381 } 382 383 /** 384 * wdtpci_ioctl: 385 * @file: file handle to the device 386 * @cmd: watchdog command 387 * @arg: argument pointer 388 * 389 * The watchdog API defines a common set of functions for all watchdogs 390 * according to their available features. We only actually usefully support 391 * querying capabilities and current status. 392 */ 393 394 static long wdtpci_ioctl(struct file *file, unsigned int cmd, 395 unsigned long arg) 396 { 397 void __user *argp = (void __user *)arg; 398 int __user *p = argp; 399 int new_heartbeat; 400 int status; 401 402 struct watchdog_info ident = { 403 .options = WDIOF_SETTIMEOUT| 404 WDIOF_MAGICCLOSE| 405 WDIOF_KEEPALIVEPING, 406 .firmware_version = 1, 407 .identity = "PCI-WDT500/501", 408 }; 409 410 /* Add options according to the card we have */ 411 ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2); 412 if (type == 501) { 413 ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER| 414 WDIOF_POWEROVER); 415 if (tachometer) 416 ident.options |= WDIOF_FANFAULT; 417 } 418 419 switch (cmd) { 420 case WDIOC_GETSUPPORT: 421 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; 422 case WDIOC_GETSTATUS: 423 wdtpci_get_status(&status); 424 return put_user(status, p); 425 case WDIOC_GETBOOTSTATUS: 426 return put_user(0, p); 427 case WDIOC_KEEPALIVE: 428 wdtpci_ping(); 429 return 0; 430 case WDIOC_SETTIMEOUT: 431 if (get_user(new_heartbeat, p)) 432 return -EFAULT; 433 if (wdtpci_set_heartbeat(new_heartbeat)) 434 return -EINVAL; 435 wdtpci_ping(); 436 /* Fall */ 437 case WDIOC_GETTIMEOUT: 438 return put_user(heartbeat, p); 439 default: 440 return -ENOTTY; 441 } 442 } 443 444 /** 445 * wdtpci_open: 446 * @inode: inode of device 447 * @file: file handle to device 448 * 449 * The watchdog device has been opened. The watchdog device is single 450 * open and on opening we load the counters. Counter zero is a 100Hz 451 * cascade, into counter 1 which downcounts to reboot. When the counter 452 * triggers counter 2 downcounts the length of the reset pulse which 453 * set set to be as long as possible. 454 */ 455 456 static int wdtpci_open(struct inode *inode, struct file *file) 457 { 458 if (test_and_set_bit(0, &open_lock)) 459 return -EBUSY; 460 461 if (nowayout) 462 __module_get(THIS_MODULE); 463 /* 464 * Activate 465 */ 466 wdtpci_start(); 467 return nonseekable_open(inode, file); 468 } 469 470 /** 471 * wdtpci_release: 472 * @inode: inode to board 473 * @file: file handle to board 474 * 475 * The watchdog has a configurable API. There is a religious dispute 476 * between people who want their watchdog to be able to shut down and 477 * those who want to be sure if the watchdog manager dies the machine 478 * reboots. In the former case we disable the counters, in the latter 479 * case you have to open it again very soon. 480 */ 481 482 static int wdtpci_release(struct inode *inode, struct file *file) 483 { 484 if (expect_close == 42) { 485 wdtpci_stop(); 486 } else { 487 printk(KERN_CRIT PFX "Unexpected close, not stopping timer!"); 488 wdtpci_ping(); 489 } 490 expect_close = 0; 491 clear_bit(0, &open_lock); 492 return 0; 493 } 494 495 /** 496 * wdtpci_temp_read: 497 * @file: file handle to the watchdog board 498 * @buf: buffer to write 1 byte into 499 * @count: length of buffer 500 * @ptr: offset (no seek allowed) 501 * 502 * Read reports the temperature in degrees Fahrenheit. The API is in 503 * fahrenheit. It was designed by an imperial measurement luddite. 504 */ 505 506 static ssize_t wdtpci_temp_read(struct file *file, char __user *buf, 507 size_t count, loff_t *ptr) 508 { 509 int temperature; 510 511 if (wdtpci_get_temperature(&temperature)) 512 return -EFAULT; 513 514 if (copy_to_user(buf, &temperature, 1)) 515 return -EFAULT; 516 517 return 1; 518 } 519 520 /** 521 * wdtpci_temp_open: 522 * @inode: inode of device 523 * @file: file handle to device 524 * 525 * The temperature device has been opened. 526 */ 527 528 static int wdtpci_temp_open(struct inode *inode, struct file *file) 529 { 530 return nonseekable_open(inode, file); 531 } 532 533 /** 534 * wdtpci_temp_release: 535 * @inode: inode to board 536 * @file: file handle to board 537 * 538 * The temperature device has been closed. 539 */ 540 541 static int wdtpci_temp_release(struct inode *inode, struct file *file) 542 { 543 return 0; 544 } 545 546 /** 547 * notify_sys: 548 * @this: our notifier block 549 * @code: the event being reported 550 * @unused: unused 551 * 552 * Our notifier is called on system shutdowns. We want to turn the card 553 * off at reboot otherwise the machine will reboot again during memory 554 * test or worse yet during the following fsck. This would suck, in fact 555 * trust me - if it happens it does suck. 556 */ 557 558 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code, 559 void *unused) 560 { 561 if (code == SYS_DOWN || code == SYS_HALT) 562 wdtpci_stop(); 563 return NOTIFY_DONE; 564 } 565 566 /* 567 * Kernel Interfaces 568 */ 569 570 571 static const struct file_operations wdtpci_fops = { 572 .owner = THIS_MODULE, 573 .llseek = no_llseek, 574 .write = wdtpci_write, 575 .unlocked_ioctl = wdtpci_ioctl, 576 .open = wdtpci_open, 577 .release = wdtpci_release, 578 }; 579 580 static struct miscdevice wdtpci_miscdev = { 581 .minor = WATCHDOG_MINOR, 582 .name = "watchdog", 583 .fops = &wdtpci_fops, 584 }; 585 586 static const struct file_operations wdtpci_temp_fops = { 587 .owner = THIS_MODULE, 588 .llseek = no_llseek, 589 .read = wdtpci_temp_read, 590 .open = wdtpci_temp_open, 591 .release = wdtpci_temp_release, 592 }; 593 594 static struct miscdevice temp_miscdev = { 595 .minor = TEMP_MINOR, 596 .name = "temperature", 597 .fops = &wdtpci_temp_fops, 598 }; 599 600 /* 601 * The WDT card needs to learn about soft shutdowns in order to 602 * turn the timebomb registers off. 603 */ 604 605 static struct notifier_block wdtpci_notifier = { 606 .notifier_call = wdtpci_notify_sys, 607 }; 608 609 610 static int __devinit wdtpci_init_one(struct pci_dev *dev, 611 const struct pci_device_id *ent) 612 { 613 int ret = -EIO; 614 615 dev_count++; 616 if (dev_count > 1) { 617 printk(KERN_ERR PFX "This driver only supports one device\n"); 618 return -ENODEV; 619 } 620 621 if (type != 500 && type != 501) { 622 printk(KERN_ERR PFX "unknown card type '%d'.\n", type); 623 return -ENODEV; 624 } 625 626 if (pci_enable_device(dev)) { 627 printk(KERN_ERR PFX "Not possible to enable PCI Device\n"); 628 return -ENODEV; 629 } 630 631 if (pci_resource_start(dev, 2) == 0x0000) { 632 printk(KERN_ERR PFX "No I/O-Address for card detected\n"); 633 ret = -ENODEV; 634 goto out_pci; 635 } 636 637 if (pci_request_region(dev, 2, "wdt_pci")) { 638 printk(KERN_ERR PFX "I/O address 0x%llx already in use\n", 639 (unsigned long long)pci_resource_start(dev, 2)); 640 goto out_pci; 641 } 642 643 irq = dev->irq; 644 io = pci_resource_start(dev, 2); 645 646 if (request_irq(irq, wdtpci_interrupt, IRQF_DISABLED | IRQF_SHARED, 647 "wdt_pci", &wdtpci_miscdev)) { 648 printk(KERN_ERR PFX "IRQ %d is not free\n", irq); 649 goto out_reg; 650 } 651 652 printk(KERN_INFO 653 "PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%llx (Interrupt %d)\n", 654 (unsigned long long)io, irq); 655 656 /* Check that the heartbeat value is within its range; 657 if not reset to the default */ 658 if (wdtpci_set_heartbeat(heartbeat)) { 659 wdtpci_set_heartbeat(WD_TIMO); 660 printk(KERN_INFO PFX 661 "heartbeat value must be 0 < heartbeat < 65536, using %d\n", 662 WD_TIMO); 663 } 664 665 ret = register_reboot_notifier(&wdtpci_notifier); 666 if (ret) { 667 printk(KERN_ERR PFX 668 "cannot register reboot notifier (err=%d)\n", ret); 669 goto out_irq; 670 } 671 672 if (type == 501) { 673 ret = misc_register(&temp_miscdev); 674 if (ret) { 675 printk(KERN_ERR PFX 676 "cannot register miscdev on minor=%d (err=%d)\n", 677 TEMP_MINOR, ret); 678 goto out_rbt; 679 } 680 } 681 682 ret = misc_register(&wdtpci_miscdev); 683 if (ret) { 684 printk(KERN_ERR PFX 685 "cannot register miscdev on minor=%d (err=%d)\n", 686 WATCHDOG_MINOR, ret); 687 goto out_misc; 688 } 689 690 printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n", 691 heartbeat, nowayout); 692 if (type == 501) 693 printk(KERN_INFO "wdt: Fan Tachometer is %s\n", 694 (tachometer ? "Enabled" : "Disabled")); 695 696 ret = 0; 697 out: 698 return ret; 699 700 out_misc: 701 if (type == 501) 702 misc_deregister(&temp_miscdev); 703 out_rbt: 704 unregister_reboot_notifier(&wdtpci_notifier); 705 out_irq: 706 free_irq(irq, &wdtpci_miscdev); 707 out_reg: 708 pci_release_region(dev, 2); 709 out_pci: 710 pci_disable_device(dev); 711 goto out; 712 } 713 714 715 static void __devexit wdtpci_remove_one(struct pci_dev *pdev) 716 { 717 /* here we assume only one device will ever have 718 * been picked up and registered by probe function */ 719 misc_deregister(&wdtpci_miscdev); 720 if (type == 501) 721 misc_deregister(&temp_miscdev); 722 unregister_reboot_notifier(&wdtpci_notifier); 723 free_irq(irq, &wdtpci_miscdev); 724 pci_release_region(pdev, 2); 725 pci_disable_device(pdev); 726 dev_count--; 727 } 728 729 730 static struct pci_device_id wdtpci_pci_tbl[] = { 731 { 732 .vendor = PCI_VENDOR_ID_ACCESSIO, 733 .device = PCI_DEVICE_ID_ACCESSIO_WDG_CSM, 734 .subvendor = PCI_ANY_ID, 735 .subdevice = PCI_ANY_ID, 736 }, 737 { 0, }, /* terminate list */ 738 }; 739 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl); 740 741 742 static struct pci_driver wdtpci_driver = { 743 .name = "wdt_pci", 744 .id_table = wdtpci_pci_tbl, 745 .probe = wdtpci_init_one, 746 .remove = __devexit_p(wdtpci_remove_one), 747 }; 748 749 750 /** 751 * wdtpci_cleanup: 752 * 753 * Unload the watchdog. You cannot do this with any file handles open. 754 * If your watchdog is set to continue ticking on close and you unload 755 * it, well it keeps ticking. We won't get the interrupt but the board 756 * will not touch PC memory so all is fine. You just have to load a new 757 * module in xx seconds or reboot. 758 */ 759 760 static void __exit wdtpci_cleanup(void) 761 { 762 pci_unregister_driver(&wdtpci_driver); 763 } 764 765 766 /** 767 * wdtpci_init: 768 * 769 * Set up the WDT watchdog board. All we have to do is grab the 770 * resources we require and bitch if anyone beat us to them. 771 * The open() function will actually kick the board off. 772 */ 773 774 static int __init wdtpci_init(void) 775 { 776 return pci_register_driver(&wdtpci_driver); 777 } 778 779 780 module_init(wdtpci_init); 781 module_exit(wdtpci_cleanup); 782 783 MODULE_AUTHOR("JP Nollmann, Alan Cox"); 784 MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards"); 785 MODULE_LICENSE("GPL"); 786 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); 787 MODULE_ALIAS_MISCDEV(TEMP_MINOR); 788