drivers/char/wdt_pci.c

   1 /*
   2  *      Industrial Computer Source WDT500/501 driver for Linux 2.1.x
   3  *
   4  *      (c) Copyright 1996-1997 Alan Cox <alan@redhat.com>, All Rights Reserved.
   5  *                              http://www.redhat.com
   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 0.08.
  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 failures
  33  */
  34
  35 #include <linux/config.h>
  36 #include <linux/module.h>
  37 #include <linux/version.h>
  38 #include <linux/types.h>
  39 #include <linux/errno.h>
  40 #include <linux/kernel.h>
  41 #include <linux/sched.h>
  42 #include <linux/miscdevice.h>
  43 #include <linux/watchdog.h>
  44 #define WDT_IS_PCI
  45 #include "wd501p.h"
  46 #include <linux/malloc.h>
  47 #include <linux/ioport.h>
  48 #include <linux/fcntl.h>
  49 #include <asm/io.h>
  50 #include <asm/uaccess.h>
  51 #include <asm/system.h>
  52 #include <linux/notifier.h>
  53 #include <linux/reboot.h>
  54 #include <linux/init.h>
  55 #include <linux/smp_lock.h>
  56
  57 #include <linux/pci.h>
  58
  59 #define PFX "wdt_pci: "
  60
  61 /*
  62  * Until Access I/O gets their application for a PCI vendor ID approved,
  63  * I don't think that it's appropriate to move these constants into the
  64  * regular pci_ids.h file. -- JPN 2000/01/18
  65  */
  66
  67 #ifndef PCI_VENDOR_ID_ACCESSIO
  68 #define PCI_VENDOR_ID_ACCESSIO 0x494f
  69 #endif
  70 #ifndef PCI_DEVICE_ID_WDG_CSM
  71 #define PCI_DEVICE_ID_WDG_CSM 0x22c0
  72 #endif
  73
  74 static int wdt_is_open;
  75
  76 /*
  77  *      You must set these - there is no sane way to probe for this board.
  78  *      You can use wdt=x,y to set these now.
  79  */
  80
  81 static int io=0x240;
  82 static int irq=11;
  83
  84 #define WD_TIMO (100*60)                /* 1 minute */
  85
  86 #ifndef MODULE
  87
  88 /**
  89  *      wdtpci_setup:
  90  *      @str: command line string
  91  *
  92  *      Setup options. The board isn't really probe-able so we have to
  93  *      get the user to tell us the configuration. Sane people build it
  94  *      modular but the others come here.
  95  */
  96
  97 static int __init wdtpci_setup(char *str)
  98 {
  99         int ints[4];
 100
 101         str = get_options (str, ARRAY_SIZE(ints), ints);
 102
 103         if (ints[0] > 0)
 104         {
 105                 io = ints[1];
 106                 if(ints[0] > 1)
 107                         irq = ints[2];
 108         }
 109
 110         return 1;
 111 }
 112
 113 __setup("wdt=", wdtpci_setup);
 114
 115 #endif /* !MODULE */
 116
 117 /*
 118  *      Programming support
 119  */
 120
 121 static void wdtpci_ctr_mode(int ctr, int mode)
 122 {
 123         ctr<<=6;
 124         ctr|=0x30;
 125         ctr|=(mode<<1);
 126         outb_p(ctr, WDT_CR);
 127 }
 128
 129 static void wdtpci_ctr_load(int ctr, int val)
 130 {
 131         outb_p(val&0xFF, WDT_COUNT0+ctr);
 132         outb_p(val>>8, WDT_COUNT0+ctr);
 133 }
 134
 135 /*
 136  *      Kernel methods.
 137  */
 138
 139
 140 /**
 141  *      wdtpci_status:
 142  *
 143  *      Extract the status information from a WDT watchdog device. There are
 144  *      several board variants so we have to know which bits are valid. Some
 145  *      bits default to one and some to zero in order to be maximally painful.
 146  *
 147  *      we then map the bits onto the status ioctl flags.
 148  */
 149
 150 static int wdtpci_status(void)
 151 {
 152         /*
 153          *      Status register to bit flags
 154          */
 155
 156         int flag=0;
 157         unsigned char status=inb_p(WDT_SR);
 158         status|=FEATUREMAP1;
 159         status&=~FEATUREMAP2;
 160
 161         if(!(status&WDC_SR_TGOOD))
 162                 flag|=WDIOF_OVERHEAT;
 163         if(!(status&WDC_SR_PSUOVER))
 164                 flag|=WDIOF_POWEROVER;
 165         if(!(status&WDC_SR_PSUUNDR))
 166                 flag|=WDIOF_POWERUNDER;
 167         if(!(status&WDC_SR_FANGOOD))
 168                 flag|=WDIOF_FANFAULT;
 169         if(status&WDC_SR_ISOI0)
 170                 flag|=WDIOF_EXTERN1;
 171         if(status&WDC_SR_ISII1)
 172                 flag|=WDIOF_EXTERN2;
 173         return flag;
 174 }
 175
 176 /**
 177  *      wdtpci_interrupt:
 178  *      @irq:           Interrupt number
 179  *      @dev_id:        Unused as we don't allow multiple devices.
 180  *      @regs:          Unused.
 181  *
 182  *      Handle an interrupt from the board. These are raised when the status
 183  *      map changes in what the board considers an interesting way. That means
 184  *      a failure condition occuring.
 185  */
 186
 187 static void wdtpci_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 188 {
 189         /*
 190          *      Read the status register see what is up and
 191          *      then printk it.
 192          */
 193
 194         unsigned char status=inb_p(WDT_SR);
 195
 196         status|=FEATUREMAP1;
 197         status&=~FEATUREMAP2;
 198
 199         printk(KERN_CRIT "WDT status %d\n", status);
 200
 201         if(!(status&WDC_SR_TGOOD))
 202                 printk(KERN_CRIT "Overheat alarm.(%d)\n",inb_p(WDT_RT));
 203         if(!(status&WDC_SR_PSUOVER))
 204                 printk(KERN_CRIT "PSU over voltage.\n");
 205         if(!(status&WDC_SR_PSUUNDR))
 206                 printk(KERN_CRIT "PSU under voltage.\n");
 207         if(!(status&WDC_SR_FANGOOD))
 208                 printk(KERN_CRIT "Possible fan fault.\n");
 209         if(!(status&WDC_SR_WCCR))
 210 #ifdef SOFTWARE_REBOOT
 211 #ifdef ONLY_TESTING
 212                 printk(KERN_CRIT "Would Reboot.\n");
 213 #else
 214                 printk(KERN_CRIT "Initiating system reboot.\n");
 215                 machine_restart(NULL);
 216 #endif
 217 #else
 218                 printk(KERN_CRIT "Reset in 5ms.\n");
 219 #endif
 220 }
 221
 222
 223 static long long wdtpci_llseek(struct file *file, long long offset, int origin)
 224 {
 225         return -ESPIPE;
 226 }
 227
 228 /**
 229  *      wdtpci_ping:
 230  *
 231  *      Reload counter one with the watchdog timeout. We don't bother reloading
 232  *      the cascade counter.
 233  */
 234
 235 static void wdtpci_ping(void)
 236 {
 237         /* Write a watchdog value */
 238         inb_p(WDT_DC);
 239         wdtpci_ctr_mode(1,2);
 240         wdtpci_ctr_load(1,WD_TIMO);             /* Timeout */
 241         outb_p(0, WDT_DC);
 242 }
 243
 244 /**
 245  *      wdtpci_write:
 246  *      @file: file handle to the watchdog
 247  *      @buf: buffer to write (unused as data does not matter here
 248  *      @count: count of bytes
 249  *      @ppos: pointer to the position to write. No seeks allowed
 250  *
 251  *      A write to a watchdog device is defined as a keepalive signal. Any
 252  *      write of data will do, as we we don't define content meaning.
 253  */
 254
 255 static ssize_t wdtpci_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
 256 {
 257         /*  Can't seek (pwrite) on this device  */
 258         if (ppos != &file->f_pos)
 259                 return -ESPIPE;
 260
 261         if(count)
 262         {
 263                 wdtpci_ping();
 264                 return 1;
 265         }
 266         return 0;
 267 }
 268
 269 /**
 270  *      wdtpci_read:
 271  *      @file: file handle to the watchdog board
 272  *      @buf: buffer to write 1 byte into
 273  *      @count: length of buffer
 274  *      @ptr: offset (no seek allowed)
 275  *
 276  *      Read reports the temperature in degrees Fahrenheit. The API is in
 277  *      fahrenheit. It was designed by an imperial measurement luddite.
 278  */
 279
 280 static ssize_t wdtpci_read(struct file *file, char *buf, size_t count, loff_t *ptr)
 281 {
 282         unsigned short c=inb_p(WDT_RT);
 283         unsigned char cp;
 284
 285         /*  Can't seek (pread) on this device  */
 286         if (ptr != &file->f_pos)
 287                 return -ESPIPE;
 288
 289         switch(MINOR(file->f_dentry->d_inode->i_rdev))
 290         {
 291                 case TEMP_MINOR:
 292                         c*=11;
 293                         c/=15;
 294                         cp=c+7;
 295                         if(copy_to_user(buf,&cp,1))
 296                                 return -EFAULT;
 297                         return 1;
 298                 default:
 299                         return -EINVAL;
 300         }
 301 }
 302
 303 /**
 304  *      wdtpci_ioctl:
 305  *      @inode: inode of the device
 306  *      @file: file handle to the device
 307  *      @cmd: watchdog command
 308  *      @arg: argument pointer
 309  *
 310  *      The watchdog API defines a common set of functions for all watchdogs
 311  *      according to their available features. We only actually usefully support
 312  *      querying capabilities and current status.
 313  */
 314
 315 static int wdtpci_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
 316         unsigned long arg)
 317 {
 318         static struct watchdog_info ident=
 319         {
 320                 WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER
 321                         |WDIOF_EXTERN1|WDIOF_EXTERN2|WDIOF_FANFAULT,
 322                 1,
 323                 "WDT500/501PCI"
 324         };
 325
 326         ident.options&=WDT_OPTION_MASK; /* Mask down to the card we have */
 327         switch(cmd)
 328         {
 329                 default:
 330                         return -ENOIOCTLCMD;
 331                 case WDIOC_GETSUPPORT:
 332                         return copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident))?-EFAULT:0;
 333
 334                 case WDIOC_GETSTATUS:
 335                         return put_user(wdtpci_status(),(int *)arg);
 336                 case WDIOC_GETBOOTSTATUS:
 337                         return put_user(0, (int *)arg);
 338                 case WDIOC_KEEPALIVE:
 339                         wdtpci_ping();
 340                         return 0;
 341         }
 342 }
 343
 344 /**
 345  *      wdtpci_open:
 346  *      @inode: inode of device
 347  *      @file: file handle to device
 348  *
 349  *      One of our two misc devices has been opened. The watchdog device is
 350  *      single open and on opening we load the counters. Counter zero is a
 351  *      100Hz cascade, into counter 1 which downcounts to reboot. When the
 352  *      counter triggers counter 2 downcounts the length of the reset pulse
 353  *      which set set to be as long as possible.
 354  */
 355
 356 static int wdtpci_open(struct inode *inode, struct file *file)
 357 {
 358         switch(MINOR(inode->i_rdev))
 359         {
 360                 case WATCHDOG_MINOR:
 361                         if(wdt_is_open)
 362                                 return -EBUSY;
 363 #ifdef CONFIG_WATCHDOG_NOWAYOUT
 364                         MOD_INC_USE_COUNT;
 365 #endif
 366                         /*
 367                          *      Activate
 368                          */
 369
 370                         wdt_is_open=1;
 371
 372                         inb_p(WDT_DC);          /* Disable */
 373
 374                         /*
 375                          * "pet" the watchdog, as Access says.
 376                          * This resets the clock outputs.
 377                          */
 378
 379                         wdtpci_ctr_mode(2,0);
 380                         outb_p(0, WDT_DC);
 381
 382                         inb_p(WDT_DC);
 383
 384                         outb_p(0, WDT_CLOCK);   /* 2.0833MHz clock */
 385                         inb_p(WDT_BUZZER);      /* disable */
 386                         inb_p(WDT_OPTONOTRST);  /* disable */
 387                         inb_p(WDT_OPTORST);     /* disable */
 388                         inb_p(WDT_PROGOUT);     /* disable */
 389                         wdtpci_ctr_mode(0,3);
 390                         wdtpci_ctr_mode(1,2);
 391                         wdtpci_ctr_mode(2,1);
 392                         wdtpci_ctr_load(0,20833);       /* count at 100Hz */
 393                         wdtpci_ctr_load(1,WD_TIMO);/* Timeout 60 seconds */
 394                         /* DO NOT LOAD CTR2 on PCI card! -- JPN */
 395                         outb_p(0, WDT_DC);      /* Enable */
 396                         return 0;
 397                 case TEMP_MINOR:
 398                         return 0;
 399                 default:
 400                         return -ENODEV;
 401         }
 402 }
 403
 404 /**
 405  *      wdtpci_close:
 406  *      @inode: inode to board
 407  *      @file: file handle to board
 408  *
 409  *      The watchdog has a configurable API. There is a religious dispute
 410  *      between people who want their watchdog to be able to shut down and
 411  *      those who want to be sure if the watchdog manager dies the machine
 412  *      reboots. In the former case we disable the counters, in the latter
 413  *      case you have to open it again very soon.
 414  */
 415
 416 static int wdtpci_release(struct inode *inode, struct file *file)
 417 {
 418         if(MINOR(inode->i_rdev)==WATCHDOG_MINOR)
 419         {
 420                 lock_kernel();
 421 #ifndef CONFIG_WATCHDOG_NOWAYOUT
 422                 inb_p(WDT_DC);          /* Disable counters */
 423                 wdtpci_ctr_load(2,0);   /* 0 length reset pulses now */
 424 #endif
 425                 wdt_is_open=0;
 426                 unlock_kernel();
 427         }
 428         return 0;
 429 }
 430
 431 /**
 432  *      notify_sys:
 433  *      @this: our notifier block
 434  *      @code: the event being reported
 435  *      @unused: unused
 436  *
 437  *      Our notifier is called on system shutdowns. We want to turn the card
 438  *      off at reboot otherwise the machine will reboot again during memory
 439  *      test or worse yet during the following fsck. This would suck, in fact
 440  *      trust me - if it happens it does suck.
 441  */
 442
 443 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
 444         void *unused)
 445 {
 446         if(code==SYS_DOWN || code==SYS_HALT)
 447         {
 448                 /* Turn the card off */
 449                 inb_p(WDT_DC);
 450                 wdtpci_ctr_load(2,0);
 451         }
 452         return NOTIFY_DONE;
 453 }
 454
 455 /*
 456  *      Kernel Interfaces
 457  */
 458
 459
 460 static struct file_operations wdtpci_fops = {
 461         owner:          THIS_MODULE,
 462         llseek:         wdtpci_llseek,
 463         read:           wdtpci_read,
 464         write:          wdtpci_write,
 465         ioctl:          wdtpci_ioctl,
 466         open:           wdtpci_open,
 467         release:        wdtpci_release,
 468 };
 469
 470 static struct miscdevice wdtpci_miscdev=
 471 {
 472         WATCHDOG_MINOR,
 473         "watchdog",
 474         &wdtpci_fops
 475 };
 476
 477 #ifdef CONFIG_WDT_501
 478 static struct miscdevice temp_miscdev=
 479 {
 480         TEMP_MINOR,
 481         "temperature",
 482         &wdtpci_fops
 483 };
 484 #endif
 485
 486 /*
 487  *      The WDT card needs to learn about soft shutdowns in order to
 488  *      turn the timebomb registers off.
 489  */
 490
 491 static struct notifier_block wdtpci_notifier=
 492 {
 493         wdtpci_notify_sys,
 494         NULL,
 495         0
 496 };
 497
 498
 499 static int __init wdtpci_init_one (struct pci_dev *dev,
 500                                    const struct pci_device_id *ent)
 501 {
 502         static int dev_count = 0;
 503         int ret = -EIO;
 504
 505         dev_count++;
 506         if (dev_count > 1) {
 507                 printk (KERN_ERR PFX
 508                         "this driver only supports 1 device\n");
 509                 return -ENODEV;
 510         }
 511
 512         irq = dev->irq;
 513         io = pci_resource_start (dev, 2);
 514         printk ("WDT501-P(PCI-WDG-CSM) driver 0.07 at %X "
 515                 "(Interrupt %d)\n", io, irq);
 516
 517         if (pci_enable_device (dev))
 518                 goto out;
 519
 520         if (request_region (io, 16, "wdt-pci") == NULL) {
 521                 printk (KERN_ERR PFX "I/O %d is not free.\n", io);
 522                 goto out;
 523         }
 524
 525         if (request_irq (irq, wdtpci_interrupt, SA_INTERRUPT | SA_SHIRQ,
 526                          "wdt-pci", &wdtpci_miscdev)) {
 527                 printk (KERN_ERR PFX "IRQ %d is not free.\n", irq);
 528                 goto out_reg;
 529         }
 530
 531         ret = misc_register (&wdtpci_miscdev);
 532         if (ret) {
 533                 printk (KERN_ERR PFX "can't misc_register on minor=%d\n", WATCHDOG_MINOR);
 534                 goto out_irq;
 535         }
 536
 537         ret = register_reboot_notifier (&wdtpci_notifier);
 538         if (ret) {
 539                 printk (KERN_ERR PFX "can't misc_register on minor=%d\n", WATCHDOG_MINOR);
 540                 goto out_misc;
 541         }
 542 #ifdef CONFIG_WDT_501
 543         ret = misc_register (&temp_miscdev);
 544         if (ret) {
 545                 printk (KERN_ERR PFX "can't misc_register (temp) on minor=%d\n", TEMP_MINOR);
 546                 goto out_rbt;
 547         }
 548 #endif
 549
 550         ret = 0;
 551 out:
 552         return ret;
 553
 554 #ifdef CONFIG_WDT_501
 555 out_rbt:
 556         unregister_reboot_notifier(&wdtpci_notifier);
 557 #endif
 558 out_misc:
 559         misc_deregister(&wdtpci_miscdev);
 560 out_irq:
 561         free_irq(irq, &wdtpci_miscdev);
 562 out_reg:
 563         release_region (io, 16);
 564         goto out;
 565 }
 566
 567
 568 static void __exit wdtpci_remove_one (struct pci_dev *pdev)
 569 {
 570         /* here we assume only one device will ever have
 571          * been picked up and registered by probe function */
 572         unregister_reboot_notifier(&wdtpci_notifier);
 573 #ifdef CONFIG_WDT_501_PCI
 574         misc_deregister(&temp_miscdev);
 575 #endif
 576         misc_deregister(&wdtpci_miscdev);
 577         free_irq(irq, &wdtpci_miscdev);
 578         release_region(io, 16);
 579 }
 580
 581
 582 static struct pci_device_id wdtpci_pci_tbl[] __initdata = {
 583         { PCI_VENDOR_ID_ACCESSIO, PCI_DEVICE_ID_WDG_CSM, PCI_ANY_ID, PCI_ANY_ID, },
 584         { 0, }, /* terminate list */
 585 };
 586 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
 587
 588
 589 static struct pci_driver wdtpci_driver = {
 590         name:           "wdt-pci",
 591         id_table:       wdtpci_pci_tbl,
 592         probe:          wdtpci_init_one,
 593         remove:         wdtpci_remove_one,
 594 };
 595
 596
 597 /**
 598  *      wdtpci_cleanup:
 599  *
 600  *      Unload the watchdog. You cannot do this with any file handles open.
 601  *      If your watchdog is set to continue ticking on close and you unload
 602  *      it, well it keeps ticking. We won't get the interrupt but the board
 603  *      will not touch PC memory so all is fine. You just have to load a new
 604  *      module in 60 seconds or reboot.
 605  */
 606
 607 static void __exit wdtpci_cleanup(void)
 608 {
 609         pci_unregister_driver (&wdtpci_driver);
 610 }
 611
 612
 613 /**
 614  *      wdtpci_init:
 615  *
 616  *      Set up the WDT watchdog board. All we have to do is grab the
 617  *      resources we require and bitch if anyone beat us to them.
 618  *      The open() function will actually kick the board off.
 619  */
 620
 621 static int __init wdtpci_init(void)
 622 {
 623         int rc = pci_register_driver (&wdtpci_driver);
 624
 625         if (rc < 1)
 626                 return -ENODEV;
 627
 628         return 0;
 629 }
 630
 631
 632 module_init(wdtpci_init);
 633 module_exit(wdtpci_cleanup);