drivers/watchdog/hpwdt.c

   1 /*
   2  *      HP WatchDog Driver
   3  *      based on
   4  *
   5  *      SoftDog 0.05:   A Software Watchdog Device
   6  *
   7  *      (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
   8  *      Thomas Mingarelli <thomas.mingarelli@hp.com>
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      version 2 as published by the Free Software Foundation
  13  *
  14  */
  15
  16 #include <linux/device.h>
  17 #include <linux/fs.h>
  18 #include <linux/init.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/io.h>
  21 #include <linux/irq.h>
  22 #include <linux/kernel.h>
  23 #include <linux/miscdevice.h>
  24 #include <linux/mm.h>
  25 #include <linux/module.h>
  26 #include <linux/kdebug.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/notifier.h>
  29 #include <linux/pci.h>
  30 #include <linux/pci_ids.h>
  31 #include <linux/reboot.h>
  32 #include <linux/sched.h>
  33 #include <linux/timer.h>
  34 #include <linux/types.h>
  35 #include <linux/uaccess.h>
  36 #include <linux/watchdog.h>
  37 #include <linux/dmi.h>
  38 #include <linux/efi.h>
  39 #include <linux/string.h>
  40 #include <linux/bootmem.h>
  41 #include <linux/slab.h>
  42 #include <asm/dmi.h>
  43 #include <asm/desc.h>
  44 #include <asm/kdebug.h>
  45
  46 #define PCI_BIOS32_SD_VALUE             0x5F32335F      /* "_32_" */
  47 #define CRU_BIOS_SIGNATURE_VALUE        0x55524324
  48 #define PCI_BIOS32_PARAGRAPH_LEN        16
  49 #define PCI_ROM_BASE1                   0x000F0000
  50 #define ROM_SIZE                        0x10000
  51
  52 struct bios32_service_dir {
  53         u32 signature;
  54         u32 entry_point;
  55         u8 revision;
  56         u8 length;
  57         u8 checksum;
  58         u8 reserved[5];
  59 };
  60
  61 /* type 212 */
  62 struct smbios_cru64_info {
  63         u8 type;
  64         u8 byte_length;
  65         u16 handle;
  66         u32 signature;
  67         u64 physical_address;
  68         u32 double_length;
  69         u32 double_offset;
  70 };
  71 #define SMBIOS_CRU64_INFORMATION        212
  72
  73 struct cmn_registers {
  74         union {
  75                 struct {
  76                         u8 ral;
  77                         u8 rah;
  78                         u16 rea2;
  79                 };
  80                 u32 reax;
  81         } u1;
  82         union {
  83                 struct {
  84                         u8 rbl;
  85                         u8 rbh;
  86                         u8 reb2l;
  87                         u8 reb2h;
  88                 };
  89                 u32 rebx;
  90         } u2;
  91         union {
  92                 struct {
  93                         u8 rcl;
  94                         u8 rch;
  95                         u16 rec2;
  96                 };
  97                 u32 recx;
  98         } u3;
  99         union {
 100                 struct {
 101                         u8 rdl;
 102                         u8 rdh;
 103                         u16 red2;
 104                 };
 105                 u32 redx;
 106         } u4;
 107
 108         u32 resi;
 109         u32 redi;
 110         u16 rds;
 111         u16 res;
 112         u32 reflags;
 113 }  __attribute__((packed));
 114
 115 #define DEFAULT_MARGIN  30
 116 static unsigned int soft_margin = DEFAULT_MARGIN;       /* in seconds */
 117 static unsigned int reload;                     /* the computed soft_margin */
 118 static int nowayout = WATCHDOG_NOWAYOUT;
 119 static char expect_release;
 120 static unsigned long hpwdt_is_open;
 121
 122 static void __iomem *pci_mem_addr;              /* the PCI-memory address */
 123 static unsigned long __iomem *hpwdt_timer_reg;
 124 static unsigned long __iomem *hpwdt_timer_con;
 125
 126 static DEFINE_SPINLOCK(rom_lock);
 127
 128 static void *cru_rom_addr;
 129
 130 static struct cmn_registers cmn_regs;
 131
 132 static struct pci_device_id hpwdt_devices[] = {
 133         {
 134          .vendor = PCI_VENDOR_ID_COMPAQ,
 135          .device = 0xB203,
 136          .subvendor = PCI_ANY_ID,
 137          .subdevice = PCI_ANY_ID,
 138         },
 139         {0},                    /* terminate list */
 140 };
 141 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
 142
 143 #ifndef CONFIG_X86_64
 144 /* --32 Bit Bios------------------------------------------------------------ */
 145
 146 #define HPWDT_ARCH      32
 147
 148 static void asminline_call(struct cmn_registers *pi86Regs,
 149                            unsigned long *pRomEntry)
 150 {
 151         asm("pushl       %ebp               \n\t"
 152             "movl        %esp, %ebp         \n\t"
 153             "pusha                          \n\t"
 154             "pushf                          \n\t"
 155             "push        %es                \n\t"
 156             "push        %ds                \n\t"
 157             "pop         %es                \n\t"
 158             "movl        8(%ebp),%eax       \n\t"
 159             "movl        4(%eax),%ebx       \n\t"
 160             "movl        8(%eax),%ecx       \n\t"
 161             "movl        12(%eax),%edx      \n\t"
 162             "movl        16(%eax),%esi      \n\t"
 163             "movl        20(%eax),%edi      \n\t"
 164             "movl        (%eax),%eax        \n\t"
 165             "push        %cs                \n\t"
 166             "call        *12(%ebp)          \n\t"
 167             "pushf                          \n\t"
 168             "pushl       %eax               \n\t"
 169             "movl        8(%ebp),%eax       \n\t"
 170             "movl        %ebx,4(%eax)       \n\t"
 171             "movl        %ecx,8(%eax)       \n\t"
 172             "movl        %edx,12(%eax)      \n\t"
 173             "movl        %esi,16(%eax)      \n\t"
 174             "movl        %edi,20(%eax)      \n\t"
 175             "movw        %ds,24(%eax)       \n\t"
 176             "movw        %es,26(%eax)       \n\t"
 177             "popl        %ebx               \n\t"
 178             "movl        %ebx,(%eax)        \n\t"
 179             "popl        %ebx               \n\t"
 180             "movl        %ebx,28(%eax)      \n\t"
 181             "pop         %es                \n\t"
 182             "popf                           \n\t"
 183             "popa                           \n\t"
 184             "leave                          \n\t" "ret");
 185 }
 186
 187 /*
 188  *      cru_detect
 189  *
 190  *      Routine Description:
 191  *      This function uses the 32-bit BIOS Service Directory record to
 192  *      search for a $CRU record.
 193  *
 194  *      Return Value:
 195  *      0        :  SUCCESS
 196  *      <0       :  FAILURE
 197  */
 198 static int __devinit cru_detect(unsigned long map_entry,
 199         unsigned long map_offset)
 200 {
 201         void *bios32_map;
 202         unsigned long *bios32_entrypoint;
 203         unsigned long cru_physical_address;
 204         unsigned long cru_length;
 205         unsigned long physical_bios_base = 0;
 206         unsigned long physical_bios_offset = 0;
 207         int retval = -ENODEV;
 208
 209         bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
 210
 211         if (bios32_map == NULL)
 212                 return -ENODEV;
 213
 214         bios32_entrypoint = bios32_map + map_offset;
 215
 216         cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
 217
 218         asminline_call(&cmn_regs, bios32_entrypoint);
 219
 220         if (cmn_regs.u1.ral != 0) {
 221                 printk(KERN_WARNING
 222                        "hpwdt: Call succeeded but with an error: 0x%x\n",
 223                        cmn_regs.u1.ral);
 224         } else {
 225                 physical_bios_base = cmn_regs.u2.rebx;
 226                 physical_bios_offset = cmn_regs.u4.redx;
 227                 cru_length = cmn_regs.u3.recx;
 228                 cru_physical_address =
 229                     physical_bios_base + physical_bios_offset;
 230
 231                 /* If the values look OK, then map it in. */
 232                 if ((physical_bios_base + physical_bios_offset)) {
 233                         cru_rom_addr =
 234                             ioremap(cru_physical_address, cru_length);
 235                         if (cru_rom_addr)
 236                                 retval = 0;
 237                 }
 238
 239                 printk(KERN_DEBUG "hpwdt: CRU Base Address:   0x%lx\n",
 240                         physical_bios_base);
 241                 printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n",
 242                         physical_bios_offset);
 243                 printk(KERN_DEBUG "hpwdt: CRU Length:         0x%lx\n",
 244                         cru_length);
 245                 printk(KERN_DEBUG "hpwdt: CRU Mapped Address: 0x%x\n",
 246                         (unsigned int)&cru_rom_addr);
 247         }
 248         iounmap(bios32_map);
 249         return retval;
 250 }
 251
 252 /*
 253  *      bios_checksum
 254  */
 255 static int __devinit bios_checksum(const char __iomem *ptr, int len)
 256 {
 257         char sum = 0;
 258         int i;
 259
 260         /*
 261          * calculate checksum of size bytes. This should add up
 262          * to zero if we have a valid header.
 263          */
 264         for (i = 0; i < len; i++)
 265                 sum += ptr[i];
 266
 267         return ((sum == 0) && (len > 0));
 268 }
 269
 270 /*
 271  *      bios32_present
 272  *
 273  *      Routine Description:
 274  *      This function finds the 32-bit BIOS Service Directory
 275  *
 276  *      Return Value:
 277  *      0        :  SUCCESS
 278  *      <0       :  FAILURE
 279  */
 280 static int __devinit bios32_present(const char __iomem *p)
 281 {
 282         struct bios32_service_dir *bios_32_ptr;
 283         int length;
 284         unsigned long map_entry, map_offset;
 285
 286         bios_32_ptr = (struct bios32_service_dir *) p;
 287
 288         /*
 289          * Search for signature by checking equal to the swizzled value
 290          * instead of calling another routine to perform a strcmp.
 291          */
 292         if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
 293                 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
 294                 if (bios_checksum(p, length)) {
 295                         /*
 296                          * According to the spec, we're looking for the
 297                          * first 4KB-aligned address below the entrypoint
 298                          * listed in the header. The Service Directory code
 299                          * is guaranteed to occupy no more than 2 4KB pages.
 300                          */
 301                         map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
 302                         map_offset = bios_32_ptr->entry_point - map_entry;
 303
 304                         return cru_detect(map_entry, map_offset);
 305                 }
 306         }
 307         return -ENODEV;
 308 }
 309
 310 static int __devinit detect_cru_service(void)
 311 {
 312         char __iomem *p, *q;
 313         int rc = -1;
 314
 315         /*
 316          * Search from 0x0f0000 through 0x0fffff, inclusive.
 317          */
 318         p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
 319         if (p == NULL)
 320                 return -ENOMEM;
 321
 322         for (q = p; q < p + ROM_SIZE; q += 16) {
 323                 rc = bios32_present(q);
 324                 if (!rc)
 325                         break;
 326         }
 327         iounmap(p);
 328         return rc;
 329 }
 330
 331 #else
 332 /* --64 Bit Bios------------------------------------------------------------ */
 333
 334 #define HPWDT_ARCH      64
 335
 336 static void asminline_call(struct cmn_registers *pi86Regs,
 337                            unsigned long *pRomEntry)
 338 {
 339         asm("pushq      %rbp            \n\t"
 340             "movq       %rsp, %rbp      \n\t"
 341             "pushq      %rax            \n\t"
 342             "pushq      %rbx            \n\t"
 343             "pushq      %rdx            \n\t"
 344             "pushq      %r12            \n\t"
 345             "pushq      %r9             \n\t"
 346             "movq       %rsi, %r12      \n\t"
 347             "movq       %rdi, %r9       \n\t"
 348             "movl       4(%r9),%ebx     \n\t"
 349             "movl       8(%r9),%ecx     \n\t"
 350             "movl       12(%r9),%edx    \n\t"
 351             "movl       16(%r9),%esi    \n\t"
 352             "movl       20(%r9),%edi    \n\t"
 353             "movl       (%r9),%eax      \n\t"
 354             "call       *%r12           \n\t"
 355             "pushfq                     \n\t"
 356             "popq        %r12           \n\t"
 357             "popfq                      \n\t"
 358             "movl       %eax, (%r9)     \n\t"
 359             "movl       %ebx, 4(%r9)    \n\t"
 360             "movl       %ecx, 8(%r9)    \n\t"
 361             "movl       %edx, 12(%r9)   \n\t"
 362             "movl       %esi, 16(%r9)   \n\t"
 363             "movl       %edi, 20(%r9)   \n\t"
 364             "movq       %r12, %rax      \n\t"
 365             "movl       %eax, 28(%r9)   \n\t"
 366             "popq       %r9             \n\t"
 367             "popq       %r12            \n\t"
 368             "popq       %rdx            \n\t"
 369             "popq       %rbx            \n\t"
 370             "popq       %rax            \n\t"
 371             "leave                      \n\t" "ret");
 372 }
 373
 374 /*
 375  *      dmi_find_cru
 376  *
 377  *      Routine Description:
 378  *      This function checks whether or not a SMBIOS/DMI record is
 379  *      the 64bit CRU info or not
 380  */
 381 static void __devinit dmi_find_cru(const struct dmi_header *dm)
 382 {
 383         struct smbios_cru64_info *smbios_cru64_ptr;
 384         unsigned long cru_physical_address;
 385
 386         if (dm->type == SMBIOS_CRU64_INFORMATION) {
 387                 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
 388                 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
 389                         cru_physical_address =
 390                             smbios_cru64_ptr->physical_address +
 391                             smbios_cru64_ptr->double_offset;
 392                         cru_rom_addr = ioremap(cru_physical_address,
 393                                     smbios_cru64_ptr->double_length);
 394                 }
 395         }
 396 }
 397
 398 static int __devinit detect_cru_service(void)
 399 {
 400         cru_rom_addr = NULL;
 401
 402         dmi_walk(dmi_find_cru);
 403
 404         /* if cru_rom_addr has been set then we found a CRU service */
 405         return ((cru_rom_addr != NULL)? 0: -ENODEV);
 406 }
 407
 408 /* ------------------------------------------------------------------------- */
 409
 410 #endif
 411
 412 /*
 413  *      NMI Handler
 414  */
 415 static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason,
 416                             void *data)
 417 {
 418         static unsigned long rom_pl;
 419         static int die_nmi_called;
 420
 421         if (ulReason != DIE_NMI && ulReason != DIE_NMI_IPI)
 422                 return NOTIFY_OK;
 423
 424         spin_lock_irqsave(&rom_lock, rom_pl);
 425         if (!die_nmi_called)
 426                 asminline_call(&cmn_regs, cru_rom_addr);
 427         die_nmi_called = 1;
 428         spin_unlock_irqrestore(&rom_lock, rom_pl);
 429         if (cmn_regs.u1.ral == 0) {
 430                 printk(KERN_WARNING "hpwdt: An NMI occurred, "
 431                        "but unable to determine source.\n");
 432         } else {
 433                 panic("An NMI occurred, please see the Integrated "
 434                         "Management Log for details.\n");
 435         }
 436
 437         return NOTIFY_STOP;
 438 }
 439
 440 /*
 441  *      Watchdog operations
 442  */
 443 static void hpwdt_start(void)
 444 {
 445         reload = (soft_margin * 1000) / 128;
 446         iowrite16(reload, hpwdt_timer_reg);
 447         iowrite16(0x85, hpwdt_timer_con);
 448 }
 449
 450 static void hpwdt_stop(void)
 451 {
 452         unsigned long data;
 453
 454         data = ioread16(hpwdt_timer_con);
 455         data &= 0xFE;
 456         iowrite16(data, hpwdt_timer_con);
 457 }
 458
 459 static void hpwdt_ping(void)
 460 {
 461         iowrite16(reload, hpwdt_timer_reg);
 462 }
 463
 464 static int hpwdt_change_timer(int new_margin)
 465 {
 466         /* Arbitrary, can't find the card's limits */
 467         if (new_margin < 30 || new_margin > 600) {
 468                 printk(KERN_WARNING
 469                         "hpwdt: New value passed in is invalid: %d seconds.\n",
 470                         new_margin);
 471                 return -EINVAL;
 472         }
 473
 474         soft_margin = new_margin;
 475         printk(KERN_DEBUG
 476                 "hpwdt: New timer passed in is %d seconds.\n",
 477                 new_margin);
 478         reload = (soft_margin * 1000) / 128;
 479
 480         return 0;
 481 }
 482
 483 /*
 484  *      /dev/watchdog handling
 485  */
 486 static int hpwdt_open(struct inode *inode, struct file *file)
 487 {
 488         /* /dev/watchdog can only be opened once */
 489         if (test_and_set_bit(0, &hpwdt_is_open))
 490                 return -EBUSY;
 491
 492         /* Start the watchdog */
 493         hpwdt_start();
 494         hpwdt_ping();
 495
 496         return nonseekable_open(inode, file);
 497 }
 498
 499 static int hpwdt_release(struct inode *inode, struct file *file)
 500 {
 501         /* Stop the watchdog */
 502         if (expect_release == 42) {
 503                 hpwdt_stop();
 504         } else {
 505                 printk(KERN_CRIT
 506                         "hpwdt: Unexpected close, not stopping watchdog!\n");
 507                 hpwdt_ping();
 508         }
 509
 510         expect_release = 0;
 511
 512         /* /dev/watchdog is being closed, make sure it can be re-opened */
 513         clear_bit(0, &hpwdt_is_open);
 514
 515         return 0;
 516 }
 517
 518 static ssize_t hpwdt_write(struct file *file, const char __user *data,
 519         size_t len, loff_t *ppos)
 520 {
 521         /* See if we got the magic character 'V' and reload the timer */
 522         if (len) {
 523                 if (!nowayout) {
 524                         size_t i;
 525
 526                         /* note: just in case someone wrote the magic character
 527                          * five months ago... */
 528                         expect_release = 0;
 529
 530                         /* scan to see whether or not we got the magic char. */
 531                         for (i = 0; i != len; i++) {
 532                                 char c;
 533                                 if (get_user(c, data+i))
 534                                         return -EFAULT;
 535                                 if (c == 'V')
 536                                         expect_release = 42;
 537                         }
 538                 }
 539
 540                 /* someone wrote to us, we should reload the timer */
 541                 hpwdt_ping();
 542         }
 543
 544         return len;
 545 }
 546
 547 static struct watchdog_info ident = {
 548         .options = WDIOF_SETTIMEOUT |
 549                    WDIOF_KEEPALIVEPING |
 550                    WDIOF_MAGICCLOSE,
 551         .identity = "HP iLO2 HW Watchdog Timer",
 552 };
 553
 554 static long hpwdt_ioctl(struct file *file, unsigned int cmd,
 555         unsigned long arg)
 556 {
 557         void __user *argp = (void __user *)arg;
 558         int __user *p = argp;
 559         int new_margin;
 560         int ret = -ENOTTY;
 561
 562         switch (cmd) {
 563         case WDIOC_GETSUPPORT:
 564                 ret = 0;
 565                 if (copy_to_user(argp, &ident, sizeof(ident)))
 566                         ret = -EFAULT;
 567                 break;
 568
 569         case WDIOC_GETSTATUS:
 570         case WDIOC_GETBOOTSTATUS:
 571                 ret = put_user(0, p);
 572                 break;
 573
 574         case WDIOC_KEEPALIVE:
 575                 hpwdt_ping();
 576                 ret = 0;
 577                 break;
 578
 579         case WDIOC_SETTIMEOUT:
 580                 ret = get_user(new_margin, p);
 581                 if (ret)
 582                         break;
 583
 584                 ret = hpwdt_change_timer(new_margin);
 585                 if (ret)
 586                         break;
 587
 588                 hpwdt_ping();
 589                 /* Fall */
 590         case WDIOC_GETTIMEOUT:
 591                 ret = put_user(soft_margin, p);
 592                 break;
 593         }
 594         return ret;
 595 }
 596
 597 /*
 598  *      Kernel interfaces
 599  */
 600 static struct file_operations hpwdt_fops = {
 601         .owner = THIS_MODULE,
 602         .llseek = no_llseek,
 603         .write = hpwdt_write,
 604         .unlocked_ioctl = hpwdt_ioctl,
 605         .open = hpwdt_open,
 606         .release = hpwdt_release,
 607 };
 608
 609 static struct miscdevice hpwdt_miscdev = {
 610         .minor = WATCHDOG_MINOR,
 611         .name = "watchdog",
 612         .fops = &hpwdt_fops,
 613 };
 614
 615 static struct notifier_block die_notifier = {
 616         .notifier_call = hpwdt_pretimeout,
 617         .priority = 0x7FFFFFFF,
 618 };
 619
 620 /*
 621  *      Init & Exit
 622  */
 623
 624 static int __devinit hpwdt_init_one(struct pci_dev *dev,
 625                                     const struct pci_device_id *ent)
 626 {
 627         int retval;
 628
 629         /*
 630          * First let's find out if we are on an iLO2 server. We will
 631          * not run on a legacy ASM box.
 632          */
 633         if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
 634                 dev_warn(&dev->dev,
 635                        "This server does not have an iLO2 ASIC.\n");
 636                 return -ENODEV;
 637         }
 638
 639         if (pci_enable_device(dev)) {
 640                 dev_warn(&dev->dev,
 641                         "Not possible to enable PCI Device: 0x%x:0x%x.\n",
 642                         ent->vendor, ent->device);
 643                 return -ENODEV;
 644         }
 645
 646         pci_mem_addr = pci_iomap(dev, 1, 0x80);
 647         if (!pci_mem_addr) {
 648                 dev_warn(&dev->dev,
 649                         "Unable to detect the iLO2 server memory.\n");
 650                 retval = -ENOMEM;
 651                 goto error_pci_iomap;
 652         }
 653         hpwdt_timer_reg = pci_mem_addr + 0x70;
 654         hpwdt_timer_con = pci_mem_addr + 0x72;
 655
 656         /* Make sure that we have a valid soft_margin */
 657         if (hpwdt_change_timer(soft_margin))
 658                 hpwdt_change_timer(DEFAULT_MARGIN);
 659
 660         /*
 661          * We need to map the ROM to get the CRU service.
 662          * For 32 bit Operating Systems we need to go through the 32 Bit
 663          * BIOS Service Directory
 664          * For 64 bit Operating Systems we get that service through SMBIOS.
 665          */
 666         retval = detect_cru_service();
 667         if (retval < 0) {
 668                 dev_warn(&dev->dev,
 669                        "Unable to detect the %d Bit CRU Service.\n",
 670                         HPWDT_ARCH);
 671                 goto error_get_cru;
 672         }
 673
 674         /*
 675          * We know this is the only CRU call we need to make so lets keep as
 676          * few instructions as possible once the NMI comes in.
 677          */
 678         cmn_regs.u1.rah = 0x0D;
 679         cmn_regs.u1.ral = 0x02;
 680
 681         retval = register_die_notifier(&die_notifier);
 682         if (retval != 0) {
 683                 dev_warn(&dev->dev,
 684                        "Unable to register a die notifier (err=%d).\n",
 685                         retval);
 686                 goto error_die_notifier;
 687         }
 688
 689         retval = misc_register(&hpwdt_miscdev);
 690         if (retval < 0) {
 691                 dev_warn(&dev->dev,
 692                         "Unable to register miscdev on minor=%d (err=%d).\n",
 693                         WATCHDOG_MINOR, retval);
 694                 goto error_misc_register;
 695         }
 696
 697         printk(KERN_INFO
 698                 "hp Watchdog Timer Driver: 1.00"
 699                 ", timer margin: %d seconds( nowayout=%d).\n",
 700                 soft_margin, nowayout);
 701
 702         return 0;
 703
 704 error_misc_register:
 705         unregister_die_notifier(&die_notifier);
 706 error_die_notifier:
 707         if (cru_rom_addr)
 708                 iounmap(cru_rom_addr);
 709 error_get_cru:
 710         pci_iounmap(dev, pci_mem_addr);
 711 error_pci_iomap:
 712         pci_disable_device(dev);
 713         return retval;
 714 }
 715
 716 static void __devexit hpwdt_exit(struct pci_dev *dev)
 717 {
 718         if (!nowayout)
 719                 hpwdt_stop();
 720
 721         misc_deregister(&hpwdt_miscdev);
 722         unregister_die_notifier(&die_notifier);
 723
 724         if (cru_rom_addr)
 725                 iounmap(cru_rom_addr);
 726         pci_iounmap(dev, pci_mem_addr);
 727         pci_disable_device(dev);
 728 }
 729
 730 static struct pci_driver hpwdt_driver = {
 731         .name = "hpwdt",
 732         .id_table = hpwdt_devices,
 733         .probe = hpwdt_init_one,
 734         .remove = __devexit_p(hpwdt_exit),
 735 };
 736
 737 static void __exit hpwdt_cleanup(void)
 738 {
 739         pci_unregister_driver(&hpwdt_driver);
 740 }
 741
 742 static int __init hpwdt_init(void)
 743 {
 744         return pci_register_driver(&hpwdt_driver);
 745 }
 746
 747 MODULE_AUTHOR("Tom Mingarelli");
 748 MODULE_DESCRIPTION("hp watchdog driver");
 749 MODULE_LICENSE("GPL");
 750 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
 751
 752 module_param(soft_margin, int, 0);
 753 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
 754
 755 module_param(nowayout, int, 0);
 756 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 757                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 758
 759 module_init(hpwdt_init);
 760 module_exit(hpwdt_cleanup);