linux/drivers/watchdog/f71808e_wdt.c
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   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
  74static unsigned short force_id;
  75module_param(force_id, ushort, 0);
  76MODULE_PARM_DESC(force_id, "Override the detected device ID");
  77
  78static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
  79static int timeout = 60;        /* default timeout in seconds */
  80module_param(timeout, int, 0);
  81MODULE_PARM_DESC(timeout,
  82        "Watchdog timeout in seconds. 1<= timeout <="
  83                        __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
  84                        __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
  85
  86static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
  87module_param(pulse_width, uint, 0);
  88MODULE_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
  92static int nowayout = WATCHDOG_NOWAYOUT;
  93module_param(nowayout, bool, 0444);
  94MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
  95
  96static unsigned int start_withtimeout;
  97module_param(start_withtimeout, uint, 0);
  98MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
  99        " given initial timeout. Zero (default) disables this feature.");
 100
 101enum chips { f71808fg, f71858fg, f71862fg, f71882fg, f71889fg };
 102
 103static const char *f71808e_names[] = {
 104        "f71808fg",
 105        "f71858fg",
 106        "f71862fg",
 107        "f71882fg",
 108        "f71889fg",
 109};
 110
 111/* Super-I/O Function prototypes */
 112static inline int superio_inb(int base, int reg);
 113static inline int superio_inw(int base, int reg);
 114static inline void superio_outb(int base, int reg, u8 val);
 115static inline void superio_set_bit(int base, int reg, int bit);
 116static inline void superio_clear_bit(int base, int reg, int bit);
 117static inline int superio_enter(int base);
 118static inline void superio_select(int base, int ld);
 119static inline void superio_exit(int base);
 120
 121struct 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
 137static struct watchdog_data watchdog = {
 138        .lock = __MUTEX_INITIALIZER(watchdog.lock),
 139};
 140
 141/* Super I/O functions */
 142static inline int superio_inb(int base, int reg)
 143{
 144        outb(reg, base);
 145        return inb(base + 1);
 146}
 147
 148static 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
 156static inline void superio_outb(int base, int reg, u8 val)
 157{
 158        outb(reg, base);
 159        outb(val, base + 1);
 160}
 161
 162static 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
 169static 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
 176static 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
 192static inline void superio_select(int base, int ld)
 193{
 194        outb(SIO_REG_LDSEL, base);
 195        outb(ld, base + 1);
 196}
 197
 198static inline void superio_exit(int base)
 199{
 200        outb(SIO_LOCK_KEY, base);
 201        release_region(base, 2);
 202}
 203
 204static 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
 228static 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
 250exit_unlock:
 251        mutex_unlock(&watchdog.lock);
 252        return err;
 253}
 254
 255static 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
 280exit_unlock:
 281        mutex_unlock(&watchdog.lock);
 282        return err;
 283}
 284
 285static 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
 352exit_superio:
 353        superio_exit(watchdog.sioaddr);
 354exit_unlock:
 355        mutex_unlock(&watchdog.lock);
 356
 357        return err;
 358}
 359
 360static 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
 375exit_unlock:
 376        mutex_unlock(&watchdog.lock);
 377
 378        return err;
 379}
 380
 381static 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
 392static 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
 411exit_unlock:
 412        mutex_unlock(&watchdog.lock);
 413        return is_running;
 414}
 415
 416/* /dev/watchdog api */
 417
 418static 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
 439static 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
 464static 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 */
 503static 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
 564static 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
 572static 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
 581static struct miscdevice watchdog_miscdev = {
 582        .minor          = WATCHDOG_MINOR,
 583        .name           = "watchdog",
 584        .fops           = &watchdog_fops,
 585};
 586
 587static struct notifier_block watchdog_notifier = {
 588        .notifier_call = watchdog_notify_sys,
 589};
 590
 591static 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
 685exit_unlock:
 686        mutex_unlock(&watchdog.lock);
 687exit_miscdev:
 688        misc_deregister(&watchdog_miscdev);
 689exit_reboot:
 690        unregister_reboot_notifier(&watchdog_notifier);
 691
 692        return err;
 693}
 694
 695static 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));
 738exit:
 739        superio_exit(sioaddr);
 740        return err;
 741}
 742
 743static 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
 760static 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
 771MODULE_DESCRIPTION("F71808E Watchdog Driver");
 772MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>");
 773MODULE_LICENSE("GPL");
 774
 775module_init(f71808e_init);
 776module_exit(f71808e_exit);
 777