drivers/watchdog/f71808e_wdt.c

   1 /***************************************************************************
   2  *   Copyright (C) 2006 by Hans Edgington <hans@edgington.nl>              *
   3  *   Copyright (C) 2007-2009 Hans de Goede <hdegoede@redhat.com>           *
   4  *   Copyright (C) 2010 Giel van Schijndel <me@mortis.eu>                  *
   5  *                                                                         *
   6  *   This program is free software; you can redistribute it and/or modify  *
   7  *   it under the terms of the GNU General Public License as published by  *
   8  *   the Free Software Foundation; either version 2 of the License, or     *
   9  *   (at your option) any later version.                                   *
  10  *                                                                         *
  11  *   This program is distributed in the hope that it will be useful,       *
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  14  *   GNU General Public License for more details.                          *
  15  *                                                                         *
  16  *   You should have received a copy of the GNU General Public License     *
  17  *   along with this program; if not, write to the                         *
  18  *   Free Software Foundation, Inc.,                                       *
  19  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  20  ***************************************************************************/
  21
  22 #include <linux/err.h>
  23 #include <linux/fs.h>
  24 #include <linux/init.h>
  25 #include <linux/io.h>
  26 #include <linux/ioport.h>
  27 #include <linux/miscdevice.h>
  28 #include <linux/module.h>
  29 #include <linux/mutex.h>
  30 #include <linux/notifier.h>
  31 #include <linux/reboot.h>
  32 #include <linux/uaccess.h>
  33 #include <linux/watchdog.h>
  34
  35 #define DRVNAME "f71808e_wdt"
  36
  37 #define SIO_F71808FG_LD_WDT     0x07    /* Watchdog timer logical device */
  38 #define SIO_UNLOCK_KEY          0x87    /* Key to enable Super-I/O */
  39 #define SIO_LOCK_KEY            0xAA    /* Key to diasble Super-I/O */
  40
  41 #define SIO_REG_LDSEL           0x07    /* Logical device select */
  42 #define SIO_REG_DEVID           0x20    /* Device ID (2 bytes) */
  43 #define SIO_REG_DEVREV          0x22    /* Device revision */
  44 #define SIO_REG_MANID           0x23    /* Fintek ID (2 bytes) */
  45 #define SIO_REG_ENABLE          0x30    /* Logical device enable */
  46 #define SIO_REG_ADDR            0x60    /* Logical device address (2 bytes) */
  47
  48 #define SIO_FINTEK_ID           0x1934  /* Manufacturers ID */
  49 #define SIO_F71808_ID           0x0901  /* Chipset ID */
  50 #define SIO_F71858_ID           0x0507  /* Chipset ID */
  51 #define SIO_F71862_ID           0x0601  /* Chipset ID */
  52 #define SIO_F71882_ID           0x0541  /* Chipset ID */
  53 #define SIO_F71889_ID           0x0723  /* Chipset ID */
  54
  55 #define F71882FG_REG_START              0x01
  56
  57 #define F71808FG_REG_WDO_CONF           0xf0
  58 #define F71808FG_REG_WDT_CONF           0xf5
  59 #define F71808FG_REG_WD_TIME            0xf6
  60
  61 #define F71808FG_FLAG_WDOUT_EN          7
  62
  63 #define F71808FG_FLAG_WDTMOUT_STS       5
  64 #define F71808FG_FLAG_WD_EN             5
  65 #define F71808FG_FLAG_WD_PULSE          4
  66 #define F71808FG_FLAG_WD_UNIT           3
  67
  68 /* Default values */
  69 #define WATCHDOG_TIMEOUT        60      /* 1 minute default timeout */
  70 #define WATCHDOG_MAX_TIMEOUT    (60 * 255)
  71 #define WATCHDOG_PULSE_WIDTH    125     /* 125 ms, default pulse width for
  72                                            watchdog signal */
  73
  74 static unsigned short force_id;
  75 module_param(force_id, ushort, 0);
  76 MODULE_PARM_DESC(force_id, "Override the detected device ID");
  77
  78 static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
  79 static int timeout = 60;        /* default timeout in seconds */
  80 module_param(timeout, int, 0);
  81 MODULE_PARM_DESC(timeout,
  82         "Watchdog timeout in seconds. 1<= timeout <="
  83                         __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
  84                         __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
  85
  86 static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
  87 module_param(pulse_width, uint, 0);
  88 MODULE_PARM_DESC(pulse_width,
  89         "Watchdog signal pulse width. 0(=level), 1 ms, 25 ms, 125 ms or 5000 ms"
  90                         " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
  91
  92 static int nowayout = WATCHDOG_NOWAYOUT;
  93 module_param(nowayout, bool, 0444);
  94 MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
  95
  96 static unsigned int start_withtimeout;
  97 module_param(start_withtimeout, uint, 0);
  98 MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
  99         " given initial timeout. Zero (default) disables this feature.");
 100
 101 enum chips { f71808fg, f71858fg, f71862fg, f71882fg, f71889fg };
 102
 103 static const char *f71808e_names[] = {
 104         "f71808fg",
 105         "f71858fg",
 106         "f71862fg",
 107         "f71882fg",
 108         "f71889fg",
 109 };
 110
 111 /* Super-I/O Function prototypes */
 112 static inline int superio_inb(int base, int reg);
 113 static inline int superio_inw(int base, int reg);
 114 static inline void superio_outb(int base, int reg, u8 val);
 115 static inline void superio_set_bit(int base, int reg, int bit);
 116 static inline void superio_clear_bit(int base, int reg, int bit);
 117 static inline int superio_enter(int base);
 118 static inline void superio_select(int base, int ld);
 119 static inline void superio_exit(int base);
 120
 121 struct watchdog_data {
 122         unsigned short  sioaddr;
 123         enum chips      type;
 124         unsigned long   opened;
 125         struct mutex    lock;
 126         char            expect_close;
 127         struct watchdog_info ident;
 128
 129         unsigned short  timeout;
 130         u8              timer_val;      /* content for the wd_time register */
 131         char            minutes_mode;
 132         u8              pulse_val;      /* pulse width flag */
 133         char            pulse_mode;     /* enable pulse output mode? */
 134         char            caused_reboot;  /* last reboot was by the watchdog */
 135 };
 136
 137 static struct watchdog_data watchdog = {
 138         .lock = __MUTEX_INITIALIZER(watchdog.lock),
 139 };
 140
 141 /* Super I/O functions */
 142 static inline int superio_inb(int base, int reg)
 143 {
 144         outb(reg, base);
 145         return inb(base + 1);
 146 }
 147
 148 static int superio_inw(int base, int reg)
 149 {
 150         int val;
 151         val  = superio_inb(base, reg) << 8;
 152         val |= superio_inb(base, reg + 1);
 153         return val;
 154 }
 155
 156 static inline void superio_outb(int base, int reg, u8 val)
 157 {
 158         outb(reg, base);
 159         outb(val, base + 1);
 160 }
 161
 162 static inline void superio_set_bit(int base, int reg, int bit)
 163 {
 164         unsigned long val = superio_inb(base, reg);
 165         __set_bit(bit, &val);
 166         superio_outb(base, reg, val);
 167 }
 168
 169 static inline void superio_clear_bit(int base, int reg, int bit)
 170 {
 171         unsigned long val = superio_inb(base, reg);
 172         __clear_bit(bit, &val);
 173         superio_outb(base, reg, val);
 174 }
 175
 176 static inline int superio_enter(int base)
 177 {
 178         /* Don't step on other drivers' I/O space by accident */
 179         if (!request_muxed_region(base, 2, DRVNAME)) {
 180                 printk(KERN_ERR DRVNAME ": I/O address 0x%04x already in use\n",
 181                                 (int)base);
 182                 return -EBUSY;
 183         }
 184
 185         /* according to the datasheet the key must be send twice! */
 186         outb(SIO_UNLOCK_KEY, base);
 187         outb(SIO_UNLOCK_KEY, base);
 188
 189         return 0;
 190 }
 191
 192 static inline void superio_select(int base, int ld)
 193 {
 194         outb(SIO_REG_LDSEL, base);
 195         outb(ld, base + 1);
 196 }
 197
 198 static inline void superio_exit(int base)
 199 {
 200         outb(SIO_LOCK_KEY, base);
 201         release_region(base, 2);
 202 }
 203
 204 static int watchdog_set_timeout(int timeout)
 205 {
 206         if (timeout <= 0
 207          || timeout >  max_timeout) {
 208                 printk(KERN_ERR DRVNAME ": watchdog timeout out of range\n");
 209                 return -EINVAL;
 210         }
 211
 212         mutex_lock(&watchdog.lock);
 213
 214         watchdog.timeout = timeout;
 215         if (timeout > 0xff) {
 216                 watchdog.timer_val = DIV_ROUND_UP(timeout, 60);
 217                 watchdog.minutes_mode = true;
 218         } else {
 219                 watchdog.timer_val = timeout;
 220                 watchdog.minutes_mode = false;
 221         }
 222
 223         mutex_unlock(&watchdog.lock);
 224
 225         return 0;
 226 }
 227
 228 static int watchdog_set_pulse_width(unsigned int pw)
 229 {
 230         int err = 0;
 231
 232         mutex_lock(&watchdog.lock);
 233
 234         if        (pw <=    1) {
 235                 watchdog.pulse_val = 0;
 236         } else if (pw <=   25) {
 237                 watchdog.pulse_val = 1;
 238         } else if (pw <=  125) {
 239                 watchdog.pulse_val = 2;
 240         } else if (pw <= 5000) {
 241                 watchdog.pulse_val = 3;
 242         } else {
 243                 printk(KERN_ERR DRVNAME ": pulse width out of range\n");
 244                 err = -EINVAL;
 245                 goto exit_unlock;
 246         }
 247
 248         watchdog.pulse_mode = pw;
 249
 250 exit_unlock:
 251         mutex_unlock(&watchdog.lock);
 252         return err;
 253 }
 254
 255 static int watchdog_keepalive(void)
 256 {
 257         int err = 0;
 258
 259         mutex_lock(&watchdog.lock);
 260         err = superio_enter(watchdog.sioaddr);
 261         if (err)
 262                 goto exit_unlock;
 263         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 264
 265         if (watchdog.minutes_mode)
 266                 /* select minutes for timer units */
 267                 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 268                                 F71808FG_FLAG_WD_UNIT);
 269         else
 270                 /* select seconds for timer units */
 271                 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 272                                 F71808FG_FLAG_WD_UNIT);
 273
 274         /* Set timer value */
 275         superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME,
 276                            watchdog.timer_val);
 277
 278         superio_exit(watchdog.sioaddr);
 279
 280 exit_unlock:
 281         mutex_unlock(&watchdog.lock);
 282         return err;
 283 }
 284
 285 static int watchdog_start(void)
 286 {
 287         /* Make sure we don't die as soon as the watchdog is enabled below */
 288         int err = watchdog_keepalive();
 289         if (err)
 290                 return err;
 291
 292         mutex_lock(&watchdog.lock);
 293         err = superio_enter(watchdog.sioaddr);
 294         if (err)
 295                 goto exit_unlock;
 296         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 297
 298         /* Watchdog pin configuration */
 299         switch (watchdog.type) {
 300         case f71808fg:
 301                 /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
 302                 superio_clear_bit(watchdog.sioaddr, 0x2a, 3);
 303                 superio_clear_bit(watchdog.sioaddr, 0x2b, 3);
 304                 break;
 305
 306         case f71882fg:
 307                 /* Set pin 56 to WDTRST# */
 308                 superio_set_bit(watchdog.sioaddr, 0x29, 1);
 309                 break;
 310
 311         case f71889fg:
 312                 /* set pin 40 to WDTRST# */
 313                 superio_outb(watchdog.sioaddr, 0x2b,
 314                                 superio_inb(watchdog.sioaddr, 0x2b) & 0xcf);
 315                 break;
 316
 317         default:
 318                 /*
 319                  * 'default' label to shut up the compiler and catch
 320                  * programmer errors
 321                  */
 322                 err = -ENODEV;
 323                 goto exit_superio;
 324         }
 325
 326         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 327         superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
 328         superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF,
 329                         F71808FG_FLAG_WDOUT_EN);
 330
 331         superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 332                         F71808FG_FLAG_WD_EN);
 333
 334         if (watchdog.pulse_mode) {
 335                 /* Select "pulse" output mode with given duration */
 336                 u8 wdt_conf = superio_inb(watchdog.sioaddr,
 337                                 F71808FG_REG_WDT_CONF);
 338
 339                 /* Set WD_PSWIDTH bits (1:0) */
 340                 wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03);
 341                 /* Set WD_PULSE to "pulse" mode */
 342                 wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
 343
 344                 superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 345                                 wdt_conf);
 346         } else {
 347                 /* Select "level" output mode */
 348                 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 349                                 F71808FG_FLAG_WD_PULSE);
 350         }
 351
 352 exit_superio:
 353         superio_exit(watchdog.sioaddr);
 354 exit_unlock:
 355         mutex_unlock(&watchdog.lock);
 356
 357         return err;
 358 }
 359
 360 static int watchdog_stop(void)
 361 {
 362         int err = 0;
 363
 364         mutex_lock(&watchdog.lock);
 365         err = superio_enter(watchdog.sioaddr);
 366         if (err)
 367                 goto exit_unlock;
 368         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 369
 370         superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 371                         F71808FG_FLAG_WD_EN);
 372
 373         superio_exit(watchdog.sioaddr);
 374
 375 exit_unlock:
 376         mutex_unlock(&watchdog.lock);
 377
 378         return err;
 379 }
 380
 381 static int watchdog_get_status(void)
 382 {
 383         int status = 0;
 384
 385         mutex_lock(&watchdog.lock);
 386         status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0;
 387         mutex_unlock(&watchdog.lock);
 388
 389         return status;
 390 }
 391
 392 static bool watchdog_is_running(void)
 393 {
 394         /*
 395          * if we fail to determine the watchdog's status assume it to be
 396          * running to be on the safe side
 397          */
 398         bool is_running = true;
 399
 400         mutex_lock(&watchdog.lock);
 401         if (superio_enter(watchdog.sioaddr))
 402                 goto exit_unlock;
 403         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 404
 405         is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0))
 406                 && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF)
 407                         & F71808FG_FLAG_WD_EN);
 408
 409         superio_exit(watchdog.sioaddr);
 410
 411 exit_unlock:
 412         mutex_unlock(&watchdog.lock);
 413         return is_running;
 414 }
 415
 416 /* /dev/watchdog api */
 417
 418 static int watchdog_open(struct inode *inode, struct file *file)
 419 {
 420         int err;
 421
 422         /* If the watchdog is alive we don't need to start it again */
 423         if (test_and_set_bit(0, &watchdog.opened))
 424                 return -EBUSY;
 425
 426         err = watchdog_start();
 427         if (err) {
 428                 clear_bit(0, &watchdog.opened);
 429                 return err;
 430         }
 431
 432         if (nowayout)
 433                 __module_get(THIS_MODULE);
 434
 435         watchdog.expect_close = 0;
 436         return nonseekable_open(inode, file);
 437 }
 438
 439 static int watchdog_release(struct inode *inode, struct file *file)
 440 {
 441         clear_bit(0, &watchdog.opened);
 442
 443         if (!watchdog.expect_close) {
 444                 watchdog_keepalive();
 445                 printk(KERN_CRIT DRVNAME
 446                         ": Unexpected close, not stopping watchdog!\n");
 447         } else if (!nowayout) {
 448                 watchdog_stop();
 449         }
 450         return 0;
 451 }
 452
 453 /*
 454  *      watchdog_write:
 455  *      @file: file handle to the watchdog
 456  *      @buf: buffer to write
 457  *      @count: count of bytes
 458  *      @ppos: pointer to the position to write. No seeks allowed
 459  *
 460  *      A write to a watchdog device is defined as a keepalive signal. Any
 461  *      write of data will do, as we we don't define content meaning.
 462  */
 463
 464 static ssize_t watchdog_write(struct file *file, const char __user *buf,
 465                             size_t count, loff_t *ppos)
 466 {
 467         if (count) {
 468                 if (!nowayout) {
 469                         size_t i;
 470
 471                         /* In case it was set long ago */
 472                         bool expect_close = false;
 473
 474                         for (i = 0; i != count; i++) {
 475                                 char c;
 476                                 if (get_user(c, buf + i))
 477                                         return -EFAULT;
 478                                 expect_close = (c == 'V');
 479                         }
 480
 481                         /* Properly order writes across fork()ed processes */
 482                         mutex_lock(&watchdog.lock);
 483                         watchdog.expect_close = expect_close;
 484                         mutex_unlock(&watchdog.lock);
 485                 }
 486
 487                 /* someone wrote to us, we should restart timer */
 488                 watchdog_keepalive();
 489         }
 490         return count;
 491 }
 492
 493 /*
 494  *      watchdog_ioctl:
 495  *      @inode: inode of the device
 496  *      @file: file handle to the device
 497  *      @cmd: watchdog command
 498  *      @arg: argument pointer
 499  *
 500  *      The watchdog API defines a common set of functions for all watchdogs
 501  *      according to their available features.
 502  */
 503 static long watchdog_ioctl(struct file *file, unsigned int cmd,
 504         unsigned long arg)
 505 {
 506         int status;
 507         int new_options;
 508         int new_timeout;
 509         union {
 510                 struct watchdog_info __user *ident;
 511                 int __user *i;
 512         } uarg;
 513
 514         uarg.i = (int __user *)arg;
 515
 516         switch (cmd) {
 517         case WDIOC_GETSUPPORT:
 518                 return copy_to_user(uarg.ident, &watchdog.ident,
 519                         sizeof(watchdog.ident)) ? -EFAULT : 0;
 520
 521         case WDIOC_GETSTATUS:
 522                 status = watchdog_get_status();
 523                 if (status < 0)
 524                         return status;
 525                 return put_user(status, uarg.i);
 526
 527         case WDIOC_GETBOOTSTATUS:
 528                 return put_user(0, uarg.i);
 529
 530         case WDIOC_SETOPTIONS:
 531                 if (get_user(new_options, uarg.i))
 532                         return -EFAULT;
 533
 534                 if (new_options & WDIOS_DISABLECARD)
 535                         watchdog_stop();
 536
 537                 if (new_options & WDIOS_ENABLECARD)
 538                         return watchdog_start();
 539
 540
 541         case WDIOC_KEEPALIVE:
 542                 watchdog_keepalive();
 543                 return 0;
 544
 545         case WDIOC_SETTIMEOUT:
 546                 if (get_user(new_timeout, uarg.i))
 547                         return -EFAULT;
 548
 549                 if (watchdog_set_timeout(new_timeout))
 550                         return -EINVAL;
 551
 552                 watchdog_keepalive();
 553                 /* Fall */
 554
 555         case WDIOC_GETTIMEOUT:
 556                 return put_user(watchdog.timeout, uarg.i);
 557
 558         default:
 559                 return -ENOTTY;
 560
 561         }
 562 }
 563
 564 static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
 565         void *unused)
 566 {
 567         if (code == SYS_DOWN || code == SYS_HALT)
 568                 watchdog_stop();
 569         return NOTIFY_DONE;
 570 }
 571
 572 static const struct file_operations watchdog_fops = {
 573         .owner          = THIS_MODULE,
 574         .llseek         = no_llseek,
 575         .open           = watchdog_open,
 576         .release        = watchdog_release,
 577         .write          = watchdog_write,
 578         .unlocked_ioctl = watchdog_ioctl,
 579 };
 580
 581 static struct miscdevice watchdog_miscdev = {
 582         .minor          = WATCHDOG_MINOR,
 583         .name           = "watchdog",
 584         .fops           = &watchdog_fops,
 585 };
 586
 587 static struct notifier_block watchdog_notifier = {
 588         .notifier_call = watchdog_notify_sys,
 589 };
 590
 591 static int __init watchdog_init(int sioaddr)
 592 {
 593         int wdt_conf, err = 0;
 594
 595         /* No need to lock watchdog.lock here because no entry points
 596          * into the module have been registered yet.
 597          */
 598         watchdog.sioaddr = sioaddr;
 599         watchdog.ident.options = WDIOC_SETTIMEOUT
 600                                 | WDIOF_MAGICCLOSE
 601                                 | WDIOF_KEEPALIVEPING;
 602
 603         snprintf(watchdog.ident.identity,
 604                 sizeof(watchdog.ident.identity), "%s watchdog",
 605                 f71808e_names[watchdog.type]);
 606
 607         err = superio_enter(sioaddr);
 608         if (err)
 609                 return err;
 610         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 611
 612         wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF);
 613         watchdog.caused_reboot = wdt_conf & F71808FG_FLAG_WDTMOUT_STS;
 614
 615         superio_exit(sioaddr);
 616
 617         err = watchdog_set_timeout(timeout);
 618         if (err)
 619                 return err;
 620         err = watchdog_set_pulse_width(pulse_width);
 621         if (err)
 622                 return err;
 623
 624         err = register_reboot_notifier(&watchdog_notifier);
 625         if (err)
 626                 return err;
 627
 628         err = misc_register(&watchdog_miscdev);
 629         if (err) {
 630                 printk(KERN_ERR DRVNAME
 631                         ": cannot register miscdev on minor=%d\n",
 632                                 watchdog_miscdev.minor);
 633                 goto exit_reboot;
 634         }
 635
 636         if (start_withtimeout) {
 637                 if (start_withtimeout <= 0
 638                  || start_withtimeout >  max_timeout) {
 639                         printk(KERN_ERR DRVNAME
 640                                 ": starting timeout out of range\n");
 641                         err = -EINVAL;
 642                         goto exit_miscdev;
 643                 }
 644
 645                 err = watchdog_start();
 646                 if (err) {
 647                         printk(KERN_ERR DRVNAME
 648                                 ": cannot start watchdog timer\n");
 649                         goto exit_miscdev;
 650                 }
 651
 652                 mutex_lock(&watchdog.lock);
 653                 err = superio_enter(sioaddr);
 654                 if (err)
 655                         goto exit_unlock;
 656                 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 657
 658                 if (start_withtimeout > 0xff) {
 659                         /* select minutes for timer units */
 660                         superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF,
 661                                 F71808FG_FLAG_WD_UNIT);
 662                         superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 663                                 DIV_ROUND_UP(start_withtimeout, 60));
 664                 } else {
 665                         /* select seconds for timer units */
 666                         superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF,
 667                                 F71808FG_FLAG_WD_UNIT);
 668                         superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 669                                 start_withtimeout);
 670                 }
 671
 672                 superio_exit(sioaddr);
 673                 mutex_unlock(&watchdog.lock);
 674
 675                 if (nowayout)
 676                         __module_get(THIS_MODULE);
 677
 678                 printk(KERN_INFO DRVNAME
 679                         ": watchdog started with initial timeout of %u sec\n",
 680                         start_withtimeout);
 681         }
 682
 683         return 0;
 684
 685 exit_unlock:
 686         mutex_unlock(&watchdog.lock);
 687 exit_miscdev:
 688         misc_deregister(&watchdog_miscdev);
 689 exit_reboot:
 690         unregister_reboot_notifier(&watchdog_notifier);
 691
 692         return err;
 693 }
 694
 695 static int __init f71808e_find(int sioaddr)
 696 {
 697         u16 devid;
 698         int err = superio_enter(sioaddr);
 699         if (err)
 700                 return err;
 701
 702         devid = superio_inw(sioaddr, SIO_REG_MANID);
 703         if (devid != SIO_FINTEK_ID) {
 704                 pr_debug(DRVNAME ": Not a Fintek device\n");
 705                 err = -ENODEV;
 706                 goto exit;
 707         }
 708
 709         devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
 710         switch (devid) {
 711         case SIO_F71808_ID:
 712                 watchdog.type = f71808fg;
 713                 break;
 714         case SIO_F71882_ID:
 715                 watchdog.type = f71882fg;
 716                 break;
 717         case SIO_F71889_ID:
 718                 watchdog.type = f71889fg;
 719                 break;
 720         case SIO_F71862_ID:
 721                 /* These have a watchdog, though it isn't implemented (yet). */
 722                 err = -ENOSYS;
 723                 goto exit;
 724         case SIO_F71858_ID:
 725                 /* Confirmed (by datasheet) not to have a watchdog. */
 726                 err = -ENODEV;
 727                 goto exit;
 728         default:
 729                 printk(KERN_INFO DRVNAME ": Unrecognized Fintek device: %04x\n",
 730                        (unsigned int)devid);
 731                 err = -ENODEV;
 732                 goto exit;
 733         }
 734
 735         printk(KERN_INFO DRVNAME ": Found %s watchdog chip, revision %d\n",
 736                 f71808e_names[watchdog.type],
 737                 (int)superio_inb(sioaddr, SIO_REG_DEVREV));
 738 exit:
 739         superio_exit(sioaddr);
 740         return err;
 741 }
 742
 743 static int __init f71808e_init(void)
 744 {
 745         static const unsigned short addrs[] = { 0x2e, 0x4e };
 746         int err = -ENODEV;
 747         int i;
 748
 749         for (i = 0; i < ARRAY_SIZE(addrs); i++) {
 750                 err = f71808e_find(addrs[i]);
 751                 if (err == 0)
 752                         break;
 753         }
 754         if (i == ARRAY_SIZE(addrs))
 755                 return err;
 756
 757         return watchdog_init(addrs[i]);
 758 }
 759
 760 static void __exit f71808e_exit(void)
 761 {
 762         if (watchdog_is_running()) {
 763                 printk(KERN_WARNING DRVNAME
 764                         ": Watchdog timer still running, stopping it\n");
 765                 watchdog_stop();
 766         }
 767         misc_deregister(&watchdog_miscdev);
 768         unregister_reboot_notifier(&watchdog_notifier);
 769 }
 770
 771 MODULE_DESCRIPTION("F71808E Watchdog Driver");
 772 MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>");
 773 MODULE_LICENSE("GPL");
 774
 775 module_init(f71808e_init);
 776 module_exit(f71808e_exit);