Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen...
[linux-2.6] / 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/desc.h>
43 #include <asm/cacheflush.h>
44
45 #define PCI_BIOS32_SD_VALUE             0x5F32335F      /* "_32_" */
46 #define CRU_BIOS_SIGNATURE_VALUE        0x55524324
47 #define PCI_BIOS32_PARAGRAPH_LEN        16
48 #define PCI_ROM_BASE1                   0x000F0000
49 #define ROM_SIZE                        0x10000
50
51 struct bios32_service_dir {
52         u32 signature;
53         u32 entry_point;
54         u8 revision;
55         u8 length;
56         u8 checksum;
57         u8 reserved[5];
58 };
59
60 /* type 212 */
61 struct smbios_cru64_info {
62         u8 type;
63         u8 byte_length;
64         u16 handle;
65         u32 signature;
66         u64 physical_address;
67         u32 double_length;
68         u32 double_offset;
69 };
70 #define SMBIOS_CRU64_INFORMATION        212
71
72 struct cmn_registers {
73         union {
74                 struct {
75                         u8 ral;
76                         u8 rah;
77                         u16 rea2;
78                 };
79                 u32 reax;
80         } u1;
81         union {
82                 struct {
83                         u8 rbl;
84                         u8 rbh;
85                         u8 reb2l;
86                         u8 reb2h;
87                 };
88                 u32 rebx;
89         } u2;
90         union {
91                 struct {
92                         u8 rcl;
93                         u8 rch;
94                         u16 rec2;
95                 };
96                 u32 recx;
97         } u3;
98         union {
99                 struct {
100                         u8 rdl;
101                         u8 rdh;
102                         u16 red2;
103                 };
104                 u32 redx;
105         } u4;
106
107         u32 resi;
108         u32 redi;
109         u16 rds;
110         u16 res;
111         u32 reflags;
112 }  __attribute__((packed));
113
114 #define DEFAULT_MARGIN  30
115 static unsigned int soft_margin = DEFAULT_MARGIN;       /* in seconds */
116 static unsigned int reload;                     /* the computed soft_margin */
117 static int nowayout = WATCHDOG_NOWAYOUT;
118 static char expect_release;
119 static unsigned long hpwdt_is_open;
120 static unsigned int allow_kdump;
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 extern asmlinkage void asminline_call(struct cmn_registers *pi86Regs, unsigned long *pRomEntry);
144
145 #ifndef CONFIG_X86_64
146 /* --32 Bit Bios------------------------------------------------------------ */
147
148 #define HPWDT_ARCH      32
149
150 asm(".text                          \n\t"
151     ".align 4                       \n"
152     "asminline_call:                \n\t"
153     "pushl       %ebp               \n\t"
154     "movl        %esp, %ebp         \n\t"
155     "pusha                          \n\t"
156     "pushf                          \n\t"
157     "push        %es                \n\t"
158     "push        %ds                \n\t"
159     "pop         %es                \n\t"
160     "movl        8(%ebp),%eax       \n\t"
161     "movl        4(%eax),%ebx       \n\t"
162     "movl        8(%eax),%ecx       \n\t"
163     "movl        12(%eax),%edx      \n\t"
164     "movl        16(%eax),%esi      \n\t"
165     "movl        20(%eax),%edi      \n\t"
166     "movl        (%eax),%eax        \n\t"
167     "push        %cs                \n\t"
168     "call        *12(%ebp)          \n\t"
169     "pushf                          \n\t"
170     "pushl       %eax               \n\t"
171     "movl        8(%ebp),%eax       \n\t"
172     "movl        %ebx,4(%eax)       \n\t"
173     "movl        %ecx,8(%eax)       \n\t"
174     "movl        %edx,12(%eax)      \n\t"
175     "movl        %esi,16(%eax)      \n\t"
176     "movl        %edi,20(%eax)      \n\t"
177     "movw        %ds,24(%eax)       \n\t"
178     "movw        %es,26(%eax)       \n\t"
179     "popl        %ebx               \n\t"
180     "movl        %ebx,(%eax)        \n\t"
181     "popl        %ebx               \n\t"
182     "movl        %ebx,28(%eax)      \n\t"
183     "pop         %es                \n\t"
184     "popf                           \n\t"
185     "popa                           \n\t"
186     "leave                          \n\t"
187     "ret                            \n\t"
188     ".previous");
189
190
191 /*
192  *      cru_detect
193  *
194  *      Routine Description:
195  *      This function uses the 32-bit BIOS Service Directory record to
196  *      search for a $CRU record.
197  *
198  *      Return Value:
199  *      0        :  SUCCESS
200  *      <0       :  FAILURE
201  */
202 static int __devinit cru_detect(unsigned long map_entry,
203         unsigned long map_offset)
204 {
205         void *bios32_map;
206         unsigned long *bios32_entrypoint;
207         unsigned long cru_physical_address;
208         unsigned long cru_length;
209         unsigned long physical_bios_base = 0;
210         unsigned long physical_bios_offset = 0;
211         int retval = -ENODEV;
212
213         bios32_map = ioremap(map_entry, (2 * PAGE_SIZE));
214
215         if (bios32_map == NULL)
216                 return -ENODEV;
217
218         bios32_entrypoint = bios32_map + map_offset;
219
220         cmn_regs.u1.reax = CRU_BIOS_SIGNATURE_VALUE;
221
222         asminline_call(&cmn_regs, bios32_entrypoint);
223
224         if (cmn_regs.u1.ral != 0) {
225                 printk(KERN_WARNING
226                         "hpwdt: Call succeeded but with an error: 0x%x\n",
227                         cmn_regs.u1.ral);
228         } else {
229                 physical_bios_base = cmn_regs.u2.rebx;
230                 physical_bios_offset = cmn_regs.u4.redx;
231                 cru_length = cmn_regs.u3.recx;
232                 cru_physical_address =
233                         physical_bios_base + physical_bios_offset;
234
235                 /* If the values look OK, then map it in. */
236                 if ((physical_bios_base + physical_bios_offset)) {
237                         cru_rom_addr =
238                                 ioremap(cru_physical_address, cru_length);
239                         if (cru_rom_addr)
240                                 retval = 0;
241                 }
242
243                 printk(KERN_DEBUG "hpwdt: CRU Base Address:   0x%lx\n",
244                         physical_bios_base);
245                 printk(KERN_DEBUG "hpwdt: CRU Offset Address: 0x%lx\n",
246                         physical_bios_offset);
247                 printk(KERN_DEBUG "hpwdt: CRU Length:         0x%lx\n",
248                         cru_length);
249                 printk(KERN_DEBUG "hpwdt: CRU Mapped Address: 0x%x\n",
250                         (unsigned int)&cru_rom_addr);
251         }
252         iounmap(bios32_map);
253         return retval;
254 }
255
256 /*
257  *      bios_checksum
258  */
259 static int __devinit bios_checksum(const char __iomem *ptr, int len)
260 {
261         char sum = 0;
262         int i;
263
264         /*
265          * calculate checksum of size bytes. This should add up
266          * to zero if we have a valid header.
267          */
268         for (i = 0; i < len; i++)
269                 sum += ptr[i];
270
271         return ((sum == 0) && (len > 0));
272 }
273
274 /*
275  *      bios32_present
276  *
277  *      Routine Description:
278  *      This function finds the 32-bit BIOS Service Directory
279  *
280  *      Return Value:
281  *      0        :  SUCCESS
282  *      <0       :  FAILURE
283  */
284 static int __devinit bios32_present(const char __iomem *p)
285 {
286         struct bios32_service_dir *bios_32_ptr;
287         int length;
288         unsigned long map_entry, map_offset;
289
290         bios_32_ptr = (struct bios32_service_dir *) p;
291
292         /*
293          * Search for signature by checking equal to the swizzled value
294          * instead of calling another routine to perform a strcmp.
295          */
296         if (bios_32_ptr->signature == PCI_BIOS32_SD_VALUE) {
297                 length = bios_32_ptr->length * PCI_BIOS32_PARAGRAPH_LEN;
298                 if (bios_checksum(p, length)) {
299                         /*
300                          * According to the spec, we're looking for the
301                          * first 4KB-aligned address below the entrypoint
302                          * listed in the header. The Service Directory code
303                          * is guaranteed to occupy no more than 2 4KB pages.
304                          */
305                         map_entry = bios_32_ptr->entry_point & ~(PAGE_SIZE - 1);
306                         map_offset = bios_32_ptr->entry_point - map_entry;
307
308                         return cru_detect(map_entry, map_offset);
309                 }
310         }
311         return -ENODEV;
312 }
313
314 static int __devinit detect_cru_service(void)
315 {
316         char __iomem *p, *q;
317         int rc = -1;
318
319         /*
320          * Search from 0x0f0000 through 0x0fffff, inclusive.
321          */
322         p = ioremap(PCI_ROM_BASE1, ROM_SIZE);
323         if (p == NULL)
324                 return -ENOMEM;
325
326         for (q = p; q < p + ROM_SIZE; q += 16) {
327                 rc = bios32_present(q);
328                 if (!rc)
329                         break;
330         }
331         iounmap(p);
332         return rc;
333 }
334
335 #else
336 /* --64 Bit Bios------------------------------------------------------------ */
337
338 #define HPWDT_ARCH      64
339
340 asm(".text                      \n\t"
341     ".align 4                   \n"
342     "asminline_call:            \n\t"
343     "pushq      %rbp            \n\t"
344     "movq       %rsp, %rbp      \n\t"
345     "pushq      %rax            \n\t"
346     "pushq      %rbx            \n\t"
347     "pushq      %rdx            \n\t"
348     "pushq      %r12            \n\t"
349     "pushq      %r9             \n\t"
350     "movq       %rsi, %r12      \n\t"
351     "movq       %rdi, %r9       \n\t"
352     "movl       4(%r9),%ebx     \n\t"
353     "movl       8(%r9),%ecx     \n\t"
354     "movl       12(%r9),%edx    \n\t"
355     "movl       16(%r9),%esi    \n\t"
356     "movl       20(%r9),%edi    \n\t"
357     "movl       (%r9),%eax      \n\t"
358     "call       *%r12           \n\t"
359     "pushfq                     \n\t"
360     "popq        %r12           \n\t"
361     "movl       %eax, (%r9)     \n\t"
362     "movl       %ebx, 4(%r9)    \n\t"
363     "movl       %ecx, 8(%r9)    \n\t"
364     "movl       %edx, 12(%r9)   \n\t"
365     "movl       %esi, 16(%r9)   \n\t"
366     "movl       %edi, 20(%r9)   \n\t"
367     "movq       %r12, %rax      \n\t"
368     "movl       %eax, 28(%r9)   \n\t"
369     "popq       %r9             \n\t"
370     "popq       %r12            \n\t"
371     "popq       %rdx            \n\t"
372     "popq       %rbx            \n\t"
373     "popq       %rax            \n\t"
374     "leave                      \n\t"
375     "ret                        \n\t"
376     ".previous");
377
378 /*
379  *      dmi_find_cru
380  *
381  *      Routine Description:
382  *      This function checks whether or not a SMBIOS/DMI record is
383  *      the 64bit CRU info or not
384  */
385 static void __devinit dmi_find_cru(const struct dmi_header *dm)
386 {
387         struct smbios_cru64_info *smbios_cru64_ptr;
388         unsigned long cru_physical_address;
389
390         if (dm->type == SMBIOS_CRU64_INFORMATION) {
391                 smbios_cru64_ptr = (struct smbios_cru64_info *) dm;
392                 if (smbios_cru64_ptr->signature == CRU_BIOS_SIGNATURE_VALUE) {
393                         cru_physical_address =
394                                 smbios_cru64_ptr->physical_address +
395                                 smbios_cru64_ptr->double_offset;
396                         cru_rom_addr = ioremap(cru_physical_address,
397                                 smbios_cru64_ptr->double_length);
398                         set_memory_x((unsigned long)cru_rom_addr & PAGE_MASK,
399                                 smbios_cru64_ptr->double_length >> PAGE_SHIFT);
400                 }
401         }
402 }
403
404 static int __devinit detect_cru_service(void)
405 {
406         cru_rom_addr = NULL;
407
408         dmi_walk(dmi_find_cru);
409
410         /* if cru_rom_addr has been set then we found a CRU service */
411         return ((cru_rom_addr != NULL) ? 0 : -ENODEV);
412 }
413
414 /* ------------------------------------------------------------------------- */
415
416 #endif
417
418 /*
419  *      Watchdog operations
420  */
421 static void hpwdt_start(void)
422 {
423         reload = (soft_margin * 1000) / 128;
424         iowrite16(reload, hpwdt_timer_reg);
425         iowrite16(0x85, hpwdt_timer_con);
426 }
427
428 static void hpwdt_stop(void)
429 {
430         unsigned long data;
431
432         data = ioread16(hpwdt_timer_con);
433         data &= 0xFE;
434         iowrite16(data, hpwdt_timer_con);
435 }
436
437 static void hpwdt_ping(void)
438 {
439         iowrite16(reload, hpwdt_timer_reg);
440 }
441
442 static int hpwdt_change_timer(int new_margin)
443 {
444         /* Arbitrary, can't find the card's limits */
445         if (new_margin < 30 || new_margin > 600) {
446                 printk(KERN_WARNING
447                         "hpwdt: New value passed in is invalid: %d seconds.\n",
448                         new_margin);
449                 return -EINVAL;
450         }
451
452         soft_margin = new_margin;
453         printk(KERN_DEBUG
454                 "hpwdt: New timer passed in is %d seconds.\n",
455                 new_margin);
456         reload = (soft_margin * 1000) / 128;
457
458         return 0;
459 }
460
461 /*
462  *      NMI Handler
463  */
464 static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason,
465                                 void *data)
466 {
467         unsigned long rom_pl;
468         static int die_nmi_called;
469
470         if (ulReason != DIE_NMI && ulReason != DIE_NMI_IPI)
471                 return NOTIFY_OK;
472
473         spin_lock_irqsave(&rom_lock, rom_pl);
474         if (!die_nmi_called)
475                 asminline_call(&cmn_regs, cru_rom_addr);
476         die_nmi_called = 1;
477         spin_unlock_irqrestore(&rom_lock, rom_pl);
478         if (cmn_regs.u1.ral == 0) {
479                 printk(KERN_WARNING "hpwdt: An NMI occurred, "
480                         "but unable to determine source.\n");
481         } else {
482                 if (allow_kdump)
483                         hpwdt_stop();
484                 panic("An NMI occurred, please see the Integrated "
485                         "Management Log for details.\n");
486         }
487
488         return NOTIFY_OK;
489 }
490
491 /*
492  *      /dev/watchdog handling
493  */
494 static int hpwdt_open(struct inode *inode, struct file *file)
495 {
496         /* /dev/watchdog can only be opened once */
497         if (test_and_set_bit(0, &hpwdt_is_open))
498                 return -EBUSY;
499
500         /* Start the watchdog */
501         hpwdt_start();
502         hpwdt_ping();
503
504         return nonseekable_open(inode, file);
505 }
506
507 static int hpwdt_release(struct inode *inode, struct file *file)
508 {
509         /* Stop the watchdog */
510         if (expect_release == 42) {
511                 hpwdt_stop();
512         } else {
513                 printk(KERN_CRIT
514                         "hpwdt: Unexpected close, not stopping watchdog!\n");
515                 hpwdt_ping();
516         }
517
518         expect_release = 0;
519
520         /* /dev/watchdog is being closed, make sure it can be re-opened */
521         clear_bit(0, &hpwdt_is_open);
522
523         return 0;
524 }
525
526 static ssize_t hpwdt_write(struct file *file, const char __user *data,
527         size_t len, loff_t *ppos)
528 {
529         /* See if we got the magic character 'V' and reload the timer */
530         if (len) {
531                 if (!nowayout) {
532                         size_t i;
533
534                         /* note: just in case someone wrote the magic character
535                          * five months ago... */
536                         expect_release = 0;
537
538                         /* scan to see whether or not we got the magic char. */
539                         for (i = 0; i != len; i++) {
540                                 char c;
541                                 if (get_user(c, data + i))
542                                         return -EFAULT;
543                                 if (c == 'V')
544                                         expect_release = 42;
545                         }
546                 }
547
548                 /* someone wrote to us, we should reload the timer */
549                 hpwdt_ping();
550         }
551
552         return len;
553 }
554
555 static struct watchdog_info ident = {
556         .options = WDIOF_SETTIMEOUT |
557                    WDIOF_KEEPALIVEPING |
558                    WDIOF_MAGICCLOSE,
559         .identity = "HP iLO2 HW Watchdog Timer",
560 };
561
562 static long hpwdt_ioctl(struct file *file, unsigned int cmd,
563         unsigned long arg)
564 {
565         void __user *argp = (void __user *)arg;
566         int __user *p = argp;
567         int new_margin;
568         int ret = -ENOTTY;
569
570         switch (cmd) {
571         case WDIOC_GETSUPPORT:
572                 ret = 0;
573                 if (copy_to_user(argp, &ident, sizeof(ident)))
574                         ret = -EFAULT;
575                 break;
576
577         case WDIOC_GETSTATUS:
578         case WDIOC_GETBOOTSTATUS:
579                 ret = put_user(0, p);
580                 break;
581
582         case WDIOC_KEEPALIVE:
583                 hpwdt_ping();
584                 ret = 0;
585                 break;
586
587         case WDIOC_SETTIMEOUT:
588                 ret = get_user(new_margin, p);
589                 if (ret)
590                         break;
591
592                 ret = hpwdt_change_timer(new_margin);
593                 if (ret)
594                         break;
595
596                 hpwdt_ping();
597                 /* Fall */
598         case WDIOC_GETTIMEOUT:
599                 ret = put_user(soft_margin, p);
600                 break;
601         }
602         return ret;
603 }
604
605 /*
606  *      Kernel interfaces
607  */
608 static struct file_operations hpwdt_fops = {
609         .owner = THIS_MODULE,
610         .llseek = no_llseek,
611         .write = hpwdt_write,
612         .unlocked_ioctl = hpwdt_ioctl,
613         .open = hpwdt_open,
614         .release = hpwdt_release,
615 };
616
617 static struct miscdevice hpwdt_miscdev = {
618         .minor = WATCHDOG_MINOR,
619         .name = "watchdog",
620         .fops = &hpwdt_fops,
621 };
622
623 static struct notifier_block die_notifier = {
624         .notifier_call = hpwdt_pretimeout,
625         .priority = 0x7FFFFFFF,
626 };
627
628 /*
629  *      Init & Exit
630  */
631
632 static int __devinit hpwdt_init_one(struct pci_dev *dev,
633                                         const struct pci_device_id *ent)
634 {
635         int retval;
636
637         /*
638          * First let's find out if we are on an iLO2 server. We will
639          * not run on a legacy ASM box.
640          * So we only support the G5 ProLiant servers and higher.
641          */
642         if (dev->subsystem_vendor != PCI_VENDOR_ID_HP) {
643                 dev_warn(&dev->dev,
644                         "This server does not have an iLO2 ASIC.\n");
645                 return -ENODEV;
646         }
647
648         if (pci_enable_device(dev)) {
649                 dev_warn(&dev->dev,
650                         "Not possible to enable PCI Device: 0x%x:0x%x.\n",
651                         ent->vendor, ent->device);
652                 return -ENODEV;
653         }
654
655         pci_mem_addr = pci_iomap(dev, 1, 0x80);
656         if (!pci_mem_addr) {
657                 dev_warn(&dev->dev,
658                         "Unable to detect the iLO2 server memory.\n");
659                 retval = -ENOMEM;
660                 goto error_pci_iomap;
661         }
662         hpwdt_timer_reg = pci_mem_addr + 0x70;
663         hpwdt_timer_con = pci_mem_addr + 0x72;
664
665         /* Make sure that we have a valid soft_margin */
666         if (hpwdt_change_timer(soft_margin))
667                 hpwdt_change_timer(DEFAULT_MARGIN);
668
669         /*
670          * We need to map the ROM to get the CRU service.
671          * For 32 bit Operating Systems we need to go through the 32 Bit
672          * BIOS Service Directory
673          * For 64 bit Operating Systems we get that service through SMBIOS.
674          */
675         retval = detect_cru_service();
676         if (retval < 0) {
677                 dev_warn(&dev->dev,
678                         "Unable to detect the %d Bit CRU Service.\n",
679                         HPWDT_ARCH);
680                 goto error_get_cru;
681         }
682
683         /*
684          * We know this is the only CRU call we need to make so lets keep as
685          * few instructions as possible once the NMI comes in.
686          */
687         cmn_regs.u1.rah = 0x0D;
688         cmn_regs.u1.ral = 0x02;
689
690         retval = register_die_notifier(&die_notifier);
691         if (retval != 0) {
692                 dev_warn(&dev->dev,
693                         "Unable to register a die notifier (err=%d).\n",
694                         retval);
695                 goto error_die_notifier;
696         }
697
698         retval = misc_register(&hpwdt_miscdev);
699         if (retval < 0) {
700                 dev_warn(&dev->dev,
701                         "Unable to register miscdev on minor=%d (err=%d).\n",
702                         WATCHDOG_MINOR, retval);
703                 goto error_misc_register;
704         }
705
706         printk(KERN_INFO
707                 "hp Watchdog Timer Driver: 1.00"
708                 ", timer margin: %d seconds (nowayout=%d)"
709                 ", allow kernel dump: %s (default = 0/OFF).\n",
710                 soft_margin, nowayout, (allow_kdump == 0) ? "OFF" : "ON");
711
712         return 0;
713
714 error_misc_register:
715         unregister_die_notifier(&die_notifier);
716 error_die_notifier:
717         if (cru_rom_addr)
718                 iounmap(cru_rom_addr);
719 error_get_cru:
720         pci_iounmap(dev, pci_mem_addr);
721 error_pci_iomap:
722         pci_disable_device(dev);
723         return retval;
724 }
725
726 static void __devexit hpwdt_exit(struct pci_dev *dev)
727 {
728         if (!nowayout)
729                 hpwdt_stop();
730
731         misc_deregister(&hpwdt_miscdev);
732         unregister_die_notifier(&die_notifier);
733
734         if (cru_rom_addr)
735                 iounmap(cru_rom_addr);
736         pci_iounmap(dev, pci_mem_addr);
737         pci_disable_device(dev);
738 }
739
740 static struct pci_driver hpwdt_driver = {
741         .name = "hpwdt",
742         .id_table = hpwdt_devices,
743         .probe = hpwdt_init_one,
744         .remove = __devexit_p(hpwdt_exit),
745 };
746
747 static void __exit hpwdt_cleanup(void)
748 {
749         pci_unregister_driver(&hpwdt_driver);
750 }
751
752 static int __init hpwdt_init(void)
753 {
754         return pci_register_driver(&hpwdt_driver);
755 }
756
757 MODULE_AUTHOR("Tom Mingarelli");
758 MODULE_DESCRIPTION("hp watchdog driver");
759 MODULE_LICENSE("GPL");
760 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
761
762 module_param(soft_margin, int, 0);
763 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
764
765 module_param(allow_kdump, int, 0);
766 MODULE_PARM_DESC(allow_kdump, "Start a kernel dump after NMI occurs");
767
768 module_param(nowayout, int, 0);
769 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
770                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
771
772 module_init(hpwdt_init);
773 module_exit(hpwdt_cleanup);