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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24#include <linux/err.h>
  25#include <linux/fs.h>
  26#include <linux/init.h>
  27#include <linux/io.h>
  28#include <linux/ioport.h>
  29#include <linux/miscdevice.h>
  30#include <linux/module.h>
  31#include <linux/mutex.h>
  32#include <linux/notifier.h>
  33#include <linux/reboot.h>
  34#include <linux/uaccess.h>
  35#include <linux/watchdog.h>
  36
  37#define DRVNAME "f71808e_wdt"
  38
  39#define SIO_F71808FG_LD_WDT     0x07    /* Watchdog timer logical device */
  40#define SIO_UNLOCK_KEY          0x87    /* Key to enable Super-I/O */
  41#define SIO_LOCK_KEY            0xAA    /* Key to disable Super-I/O */
  42
  43#define SIO_REG_LDSEL           0x07    /* Logical device select */
  44#define SIO_REG_DEVID           0x20    /* Device ID (2 bytes) */
  45#define SIO_REG_DEVREV          0x22    /* Device revision */
  46#define SIO_REG_MANID           0x23    /* Fintek ID (2 bytes) */
  47#define SIO_REG_ROM_ADDR_SEL    0x27    /* ROM address select */
  48#define SIO_F81866_REG_PORT_SEL 0x27    /* F81866 Multi-Function Register */
  49#define SIO_REG_MFUNCT1         0x29    /* Multi function select 1 */
  50#define SIO_REG_MFUNCT2         0x2a    /* Multi function select 2 */
  51#define SIO_REG_MFUNCT3         0x2b    /* Multi function select 3 */
  52#define SIO_F81866_REG_GPIO1    0x2c    /* F81866 GPIO1 Enable Register */
  53#define SIO_REG_ENABLE          0x30    /* Logical device enable */
  54#define SIO_REG_ADDR            0x60    /* Logical device address (2 bytes) */
  55
  56#define SIO_FINTEK_ID           0x1934  /* Manufacturers ID */
  57#define SIO_F71808_ID           0x0901  /* Chipset ID */
  58#define SIO_F71858_ID           0x0507  /* Chipset ID */
  59#define SIO_F71862_ID           0x0601  /* Chipset ID */
  60#define SIO_F71868_ID           0x1106  /* Chipset ID */
  61#define SIO_F71869_ID           0x0814  /* Chipset ID */
  62#define SIO_F71869A_ID          0x1007  /* Chipset ID */
  63#define SIO_F71882_ID           0x0541  /* Chipset ID */
  64#define SIO_F71889_ID           0x0723  /* Chipset ID */
  65#define SIO_F81865_ID           0x0704  /* Chipset ID */
  66#define SIO_F81866_ID           0x1010  /* Chipset ID */
  67
  68#define F71808FG_REG_WDO_CONF           0xf0
  69#define F71808FG_REG_WDT_CONF           0xf5
  70#define F71808FG_REG_WD_TIME            0xf6
  71
  72#define F71808FG_FLAG_WDOUT_EN          7
  73
  74#define F71808FG_FLAG_WDTMOUT_STS       6
  75#define F71808FG_FLAG_WD_EN             5
  76#define F71808FG_FLAG_WD_PULSE          4
  77#define F71808FG_FLAG_WD_UNIT           3
  78
  79#define F81865_REG_WDO_CONF             0xfa
  80#define F81865_FLAG_WDOUT_EN            0
  81
  82/* Default values */
  83#define WATCHDOG_TIMEOUT        60      /* 1 minute default timeout */
  84#define WATCHDOG_MAX_TIMEOUT    (60 * 255)
  85#define WATCHDOG_PULSE_WIDTH    125     /* 125 ms, default pulse width for
  86                                           watchdog signal */
  87#define WATCHDOG_F71862FG_PIN   63      /* default watchdog reset output
  88                                           pin number 63 */
  89
  90static unsigned short force_id;
  91module_param(force_id, ushort, 0);
  92MODULE_PARM_DESC(force_id, "Override the detected device ID");
  93
  94static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
  95static int timeout = WATCHDOG_TIMEOUT;  /* default timeout in seconds */
  96module_param(timeout, int, 0);
  97MODULE_PARM_DESC(timeout,
  98        "Watchdog timeout in seconds. 1<= timeout <="
  99                        __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
 100                        __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
 101
 102static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
 103module_param(pulse_width, uint, 0);
 104MODULE_PARM_DESC(pulse_width,
 105        "Watchdog signal pulse width. 0(=level), 1, 25, 30, 125, 150, 5000 or 6000 ms"
 106                        " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
 107
 108static unsigned int f71862fg_pin = WATCHDOG_F71862FG_PIN;
 109module_param(f71862fg_pin, uint, 0);
 110MODULE_PARM_DESC(f71862fg_pin,
 111        "Watchdog f71862fg reset output pin configuration. Choose pin 56 or 63"
 112                        " (default=" __MODULE_STRING(WATCHDOG_F71862FG_PIN)")");
 113
 114static bool nowayout = WATCHDOG_NOWAYOUT;
 115module_param(nowayout, bool, 0444);
 116MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
 117
 118static unsigned int start_withtimeout;
 119module_param(start_withtimeout, uint, 0);
 120MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
 121        " given initial timeout. Zero (default) disables this feature.");
 122
 123enum chips { f71808fg, f71858fg, f71862fg, f71868, f71869, f71882fg, f71889fg,
 124             f81865, f81866};
 125
 126static const char *f71808e_names[] = {
 127        "f71808fg",
 128        "f71858fg",
 129        "f71862fg",
 130        "f71868",
 131        "f71869",
 132        "f71882fg",
 133        "f71889fg",
 134        "f81865",
 135        "f81866",
 136};
 137
 138/* Super-I/O Function prototypes */
 139static inline int superio_inb(int base, int reg);
 140static inline int superio_inw(int base, int reg);
 141static inline void superio_outb(int base, int reg, u8 val);
 142static inline void superio_set_bit(int base, int reg, int bit);
 143static inline void superio_clear_bit(int base, int reg, int bit);
 144static inline int superio_enter(int base);
 145static inline void superio_select(int base, int ld);
 146static inline void superio_exit(int base);
 147
 148struct watchdog_data {
 149        unsigned short  sioaddr;
 150        enum chips      type;
 151        unsigned long   opened;
 152        struct mutex    lock;
 153        char            expect_close;
 154        struct watchdog_info ident;
 155
 156        unsigned short  timeout;
 157        u8              timer_val;      /* content for the wd_time register */
 158        char            minutes_mode;
 159        u8              pulse_val;      /* pulse width flag */
 160        char            pulse_mode;     /* enable pulse output mode? */
 161        char            caused_reboot;  /* last reboot was by the watchdog */
 162};
 163
 164static struct watchdog_data watchdog = {
 165        .lock = __MUTEX_INITIALIZER(watchdog.lock),
 166};
 167
 168/* Super I/O functions */
 169static inline int superio_inb(int base, int reg)
 170{
 171        outb(reg, base);
 172        return inb(base + 1);
 173}
 174
 175static int superio_inw(int base, int reg)
 176{
 177        int val;
 178        val  = superio_inb(base, reg) << 8;
 179        val |= superio_inb(base, reg + 1);
 180        return val;
 181}
 182
 183static inline void superio_outb(int base, int reg, u8 val)
 184{
 185        outb(reg, base);
 186        outb(val, base + 1);
 187}
 188
 189static inline void superio_set_bit(int base, int reg, int bit)
 190{
 191        unsigned long val = superio_inb(base, reg);
 192        __set_bit(bit, &val);
 193        superio_outb(base, reg, val);
 194}
 195
 196static inline void superio_clear_bit(int base, int reg, int bit)
 197{
 198        unsigned long val = superio_inb(base, reg);
 199        __clear_bit(bit, &val);
 200        superio_outb(base, reg, val);
 201}
 202
 203static inline int superio_enter(int base)
 204{
 205        /* Don't step on other drivers' I/O space by accident */
 206        if (!request_muxed_region(base, 2, DRVNAME)) {
 207                pr_err("I/O address 0x%04x already in use\n", (int)base);
 208                return -EBUSY;
 209        }
 210
 211        /* according to the datasheet the key must be sent twice! */
 212        outb(SIO_UNLOCK_KEY, base);
 213        outb(SIO_UNLOCK_KEY, base);
 214
 215        return 0;
 216}
 217
 218static inline void superio_select(int base, int ld)
 219{
 220        outb(SIO_REG_LDSEL, base);
 221        outb(ld, base + 1);
 222}
 223
 224static inline void superio_exit(int base)
 225{
 226        outb(SIO_LOCK_KEY, base);
 227        release_region(base, 2);
 228}
 229
 230static int watchdog_set_timeout(int timeout)
 231{
 232        if (timeout <= 0
 233         || timeout >  max_timeout) {
 234                pr_err("watchdog timeout out of range\n");
 235                return -EINVAL;
 236        }
 237
 238        mutex_lock(&watchdog.lock);
 239
 240        watchdog.timeout = timeout;
 241        if (timeout > 0xff) {
 242                watchdog.timer_val = DIV_ROUND_UP(timeout, 60);
 243                watchdog.minutes_mode = true;
 244        } else {
 245                watchdog.timer_val = timeout;
 246                watchdog.minutes_mode = false;
 247        }
 248
 249        mutex_unlock(&watchdog.lock);
 250
 251        return 0;
 252}
 253
 254static int watchdog_set_pulse_width(unsigned int pw)
 255{
 256        int err = 0;
 257        unsigned int t1 = 25, t2 = 125, t3 = 5000;
 258
 259        if (watchdog.type == f71868) {
 260                t1 = 30;
 261                t2 = 150;
 262                t3 = 6000;
 263        }
 264
 265        mutex_lock(&watchdog.lock);
 266
 267        if        (pw <=  1) {
 268                watchdog.pulse_val = 0;
 269        } else if (pw <= t1) {
 270                watchdog.pulse_val = 1;
 271        } else if (pw <= t2) {
 272                watchdog.pulse_val = 2;
 273        } else if (pw <= t3) {
 274                watchdog.pulse_val = 3;
 275        } else {
 276                pr_err("pulse width out of range\n");
 277                err = -EINVAL;
 278                goto exit_unlock;
 279        }
 280
 281        watchdog.pulse_mode = pw;
 282
 283exit_unlock:
 284        mutex_unlock(&watchdog.lock);
 285        return err;
 286}
 287
 288static int watchdog_keepalive(void)
 289{
 290        int err = 0;
 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        if (watchdog.minutes_mode)
 299                /* select minutes for timer units */
 300                superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 301                                F71808FG_FLAG_WD_UNIT);
 302        else
 303                /* select seconds for timer units */
 304                superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 305                                F71808FG_FLAG_WD_UNIT);
 306
 307        /* Set timer value */
 308        superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME,
 309                           watchdog.timer_val);
 310
 311        superio_exit(watchdog.sioaddr);
 312
 313exit_unlock:
 314        mutex_unlock(&watchdog.lock);
 315        return err;
 316}
 317
 318static int f71862fg_pin_configure(unsigned short ioaddr)
 319{
 320        /* When ioaddr is non-zero the calling function has to take care of
 321           mutex handling and superio preparation! */
 322
 323        if (f71862fg_pin == 63) {
 324                if (ioaddr) {
 325                        /* SPI must be disabled first to use this pin! */
 326                        superio_clear_bit(ioaddr, SIO_REG_ROM_ADDR_SEL, 6);
 327                        superio_set_bit(ioaddr, SIO_REG_MFUNCT3, 4);
 328                }
 329        } else if (f71862fg_pin == 56) {
 330                if (ioaddr)
 331                        superio_set_bit(ioaddr, SIO_REG_MFUNCT1, 1);
 332        } else {
 333                pr_err("Invalid argument f71862fg_pin=%d\n", f71862fg_pin);
 334                return -EINVAL;
 335        }
 336        return 0;
 337}
 338
 339static int watchdog_start(void)
 340{
 341        /* Make sure we don't die as soon as the watchdog is enabled below */
 342        int err = watchdog_keepalive();
 343        if (err)
 344                return err;
 345
 346        mutex_lock(&watchdog.lock);
 347        err = superio_enter(watchdog.sioaddr);
 348        if (err)
 349                goto exit_unlock;
 350        superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 351
 352        /* Watchdog pin configuration */
 353        switch (watchdog.type) {
 354        case f71808fg:
 355                /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
 356                superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT2, 3);
 357                superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 3);
 358                break;
 359
 360        case f71862fg:
 361                err = f71862fg_pin_configure(watchdog.sioaddr);
 362                if (err)
 363                        goto exit_superio;
 364                break;
 365
 366        case f71868:
 367        case f71869:
 368                /* GPIO14 --> WDTRST# */
 369                superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 4);
 370                break;
 371
 372        case f71882fg:
 373                /* Set pin 56 to WDTRST# */
 374                superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
 375                break;
 376
 377        case f71889fg:
 378                /* set pin 40 to WDTRST# */
 379                superio_outb(watchdog.sioaddr, SIO_REG_MFUNCT3,
 380                        superio_inb(watchdog.sioaddr, SIO_REG_MFUNCT3) & 0xcf);
 381                break;
 382
 383        case f81865:
 384                /* Set pin 70 to WDTRST# */
 385                superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 5);
 386                break;
 387
 388        case f81866:
 389                /* Set pin 70 to WDTRST# */
 390                superio_clear_bit(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL,
 391                                  BIT(3) | BIT(0));
 392                superio_set_bit(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL,
 393                                BIT(2));
 394                /*
 395                 * GPIO1 Control Register when 27h BIT3:2 = 01 & BIT0 = 0.
 396                 * The PIN 70(GPIO15/WDTRST) is controlled by 2Ch:
 397                 *     BIT5: 0 -> WDTRST#
 398                 *           1 -> GPIO15
 399                 */
 400                superio_clear_bit(watchdog.sioaddr, SIO_F81866_REG_GPIO1,
 401                                  BIT(5));
 402                break;
 403
 404        default:
 405                /*
 406                 * 'default' label to shut up the compiler and catch
 407                 * programmer errors
 408                 */
 409                err = -ENODEV;
 410                goto exit_superio;
 411        }
 412
 413        superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 414        superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
 415
 416        if (watchdog.type == f81865 || watchdog.type == f81866)
 417                superio_set_bit(watchdog.sioaddr, F81865_REG_WDO_CONF,
 418                                F81865_FLAG_WDOUT_EN);
 419        else
 420                superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF,
 421                                F71808FG_FLAG_WDOUT_EN);
 422
 423        superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 424                        F71808FG_FLAG_WD_EN);
 425
 426        if (watchdog.pulse_mode) {
 427                /* Select "pulse" output mode with given duration */
 428                u8 wdt_conf = superio_inb(watchdog.sioaddr,
 429                                F71808FG_REG_WDT_CONF);
 430
 431                /* Set WD_PSWIDTH bits (1:0) */
 432                wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03);
 433                /* Set WD_PULSE to "pulse" mode */
 434                wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
 435
 436                superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 437                                wdt_conf);
 438        } else {
 439                /* Select "level" output mode */
 440                superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 441                                F71808FG_FLAG_WD_PULSE);
 442        }
 443
 444exit_superio:
 445        superio_exit(watchdog.sioaddr);
 446exit_unlock:
 447        mutex_unlock(&watchdog.lock);
 448
 449        return err;
 450}
 451
 452static int watchdog_stop(void)
 453{
 454        int err = 0;
 455
 456        mutex_lock(&watchdog.lock);
 457        err = superio_enter(watchdog.sioaddr);
 458        if (err)
 459                goto exit_unlock;
 460        superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 461
 462        superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 463                        F71808FG_FLAG_WD_EN);
 464
 465        superio_exit(watchdog.sioaddr);
 466
 467exit_unlock:
 468        mutex_unlock(&watchdog.lock);
 469
 470        return err;
 471}
 472
 473static int watchdog_get_status(void)
 474{
 475        int status = 0;
 476
 477        mutex_lock(&watchdog.lock);
 478        status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0;
 479        mutex_unlock(&watchdog.lock);
 480
 481        return status;
 482}
 483
 484static bool watchdog_is_running(void)
 485{
 486        /*
 487         * if we fail to determine the watchdog's status assume it to be
 488         * running to be on the safe side
 489         */
 490        bool is_running = true;
 491
 492        mutex_lock(&watchdog.lock);
 493        if (superio_enter(watchdog.sioaddr))
 494                goto exit_unlock;
 495        superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 496
 497        is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0))
 498                && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF)
 499                        & F71808FG_FLAG_WD_EN);
 500
 501        superio_exit(watchdog.sioaddr);
 502
 503exit_unlock:
 504        mutex_unlock(&watchdog.lock);
 505        return is_running;
 506}
 507
 508/* /dev/watchdog api */
 509
 510static int watchdog_open(struct inode *inode, struct file *file)
 511{
 512        int err;
 513
 514        /* If the watchdog is alive we don't need to start it again */
 515        if (test_and_set_bit(0, &watchdog.opened))
 516                return -EBUSY;
 517
 518        err = watchdog_start();
 519        if (err) {
 520                clear_bit(0, &watchdog.opened);
 521                return err;
 522        }
 523
 524        if (nowayout)
 525                __module_get(THIS_MODULE);
 526
 527        watchdog.expect_close = 0;
 528        return nonseekable_open(inode, file);
 529}
 530
 531static int watchdog_release(struct inode *inode, struct file *file)
 532{
 533        clear_bit(0, &watchdog.opened);
 534
 535        if (!watchdog.expect_close) {
 536                watchdog_keepalive();
 537                pr_crit("Unexpected close, not stopping watchdog!\n");
 538        } else if (!nowayout) {
 539                watchdog_stop();
 540        }
 541        return 0;
 542}
 543
 544/*
 545 *      watchdog_write:
 546 *      @file: file handle to the watchdog
 547 *      @buf: buffer to write
 548 *      @count: count of bytes
 549 *      @ppos: pointer to the position to write. No seeks allowed
 550 *
 551 *      A write to a watchdog device is defined as a keepalive signal. Any
 552 *      write of data will do, as we we don't define content meaning.
 553 */
 554
 555static ssize_t watchdog_write(struct file *file, const char __user *buf,
 556                            size_t count, loff_t *ppos)
 557{
 558        if (count) {
 559                if (!nowayout) {
 560                        size_t i;
 561
 562                        /* In case it was set long ago */
 563                        bool expect_close = false;
 564
 565                        for (i = 0; i != count; i++) {
 566                                char c;
 567                                if (get_user(c, buf + i))
 568                                        return -EFAULT;
 569                                expect_close = (c == 'V');
 570                        }
 571
 572                        /* Properly order writes across fork()ed processes */
 573                        mutex_lock(&watchdog.lock);
 574                        watchdog.expect_close = expect_close;
 575                        mutex_unlock(&watchdog.lock);
 576                }
 577
 578                /* someone wrote to us, we should restart timer */
 579                watchdog_keepalive();
 580        }
 581        return count;
 582}
 583
 584/*
 585 *      watchdog_ioctl:
 586 *      @inode: inode of the device
 587 *      @file: file handle to the device
 588 *      @cmd: watchdog command
 589 *      @arg: argument pointer
 590 *
 591 *      The watchdog API defines a common set of functions for all watchdogs
 592 *      according to their available features.
 593 */
 594static long watchdog_ioctl(struct file *file, unsigned int cmd,
 595        unsigned long arg)
 596{
 597        int status;
 598        int new_options;
 599        int new_timeout;
 600        union {
 601                struct watchdog_info __user *ident;
 602                int __user *i;
 603        } uarg;
 604
 605        uarg.i = (int __user *)arg;
 606
 607        switch (cmd) {
 608        case WDIOC_GETSUPPORT:
 609                return copy_to_user(uarg.ident, &watchdog.ident,
 610                        sizeof(watchdog.ident)) ? -EFAULT : 0;
 611
 612        case WDIOC_GETSTATUS:
 613                status = watchdog_get_status();
 614                if (status < 0)
 615                        return status;
 616                return put_user(status, uarg.i);
 617
 618        case WDIOC_GETBOOTSTATUS:
 619                return put_user(0, uarg.i);
 620
 621        case WDIOC_SETOPTIONS:
 622                if (get_user(new_options, uarg.i))
 623                        return -EFAULT;
 624
 625                if (new_options & WDIOS_DISABLECARD)
 626                        watchdog_stop();
 627
 628                if (new_options & WDIOS_ENABLECARD)
 629                        return watchdog_start();
 630
 631
 632        case WDIOC_KEEPALIVE:
 633                watchdog_keepalive();
 634                return 0;
 635
 636        case WDIOC_SETTIMEOUT:
 637                if (get_user(new_timeout, uarg.i))
 638                        return -EFAULT;
 639
 640                if (watchdog_set_timeout(new_timeout))
 641                        return -EINVAL;
 642
 643                watchdog_keepalive();
 644                /* Fall */
 645
 646        case WDIOC_GETTIMEOUT:
 647                return put_user(watchdog.timeout, uarg.i);
 648
 649        default:
 650                return -ENOTTY;
 651
 652        }
 653}
 654
 655static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
 656        void *unused)
 657{
 658        if (code == SYS_DOWN || code == SYS_HALT)
 659                watchdog_stop();
 660        return NOTIFY_DONE;
 661}
 662
 663static const struct file_operations watchdog_fops = {
 664        .owner          = THIS_MODULE,
 665        .llseek         = no_llseek,
 666        .open           = watchdog_open,
 667        .release        = watchdog_release,
 668        .write          = watchdog_write,
 669        .unlocked_ioctl = watchdog_ioctl,
 670};
 671
 672static struct miscdevice watchdog_miscdev = {
 673        .minor          = WATCHDOG_MINOR,
 674        .name           = "watchdog",
 675        .fops           = &watchdog_fops,
 676};
 677
 678static struct notifier_block watchdog_notifier = {
 679        .notifier_call = watchdog_notify_sys,
 680};
 681
 682static int __init watchdog_init(int sioaddr)
 683{
 684        int wdt_conf, err = 0;
 685
 686        /* No need to lock watchdog.lock here because no entry points
 687         * into the module have been registered yet.
 688         */
 689        watchdog.sioaddr = sioaddr;
 690        watchdog.ident.options = WDIOC_SETTIMEOUT
 691                                | WDIOF_MAGICCLOSE
 692                                | WDIOF_KEEPALIVEPING;
 693
 694        snprintf(watchdog.ident.identity,
 695                sizeof(watchdog.ident.identity), "%s watchdog",
 696                f71808e_names[watchdog.type]);
 697
 698        err = superio_enter(sioaddr);
 699        if (err)
 700                return err;
 701        superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 702
 703        wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF);
 704        watchdog.caused_reboot = wdt_conf & BIT(F71808FG_FLAG_WDTMOUT_STS);
 705
 706        superio_exit(sioaddr);
 707
 708        err = watchdog_set_timeout(timeout);
 709        if (err)
 710                return err;
 711        err = watchdog_set_pulse_width(pulse_width);
 712        if (err)
 713                return err;
 714
 715        err = register_reboot_notifier(&watchdog_notifier);
 716        if (err)
 717                return err;
 718
 719        err = misc_register(&watchdog_miscdev);
 720        if (err) {
 721                pr_err("cannot register miscdev on minor=%d\n",
 722                       watchdog_miscdev.minor);
 723                goto exit_reboot;
 724        }
 725
 726        if (start_withtimeout) {
 727                if (start_withtimeout <= 0
 728                 || start_withtimeout >  max_timeout) {
 729                        pr_err("starting timeout out of range\n");
 730                        err = -EINVAL;
 731                        goto exit_miscdev;
 732                }
 733
 734                err = watchdog_start();
 735                if (err) {
 736                        pr_err("cannot start watchdog timer\n");
 737                        goto exit_miscdev;
 738                }
 739
 740                mutex_lock(&watchdog.lock);
 741                err = superio_enter(sioaddr);
 742                if (err)
 743                        goto exit_unlock;
 744                superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 745
 746                if (start_withtimeout > 0xff) {
 747                        /* select minutes for timer units */
 748                        superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF,
 749                                F71808FG_FLAG_WD_UNIT);
 750                        superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 751                                DIV_ROUND_UP(start_withtimeout, 60));
 752                } else {
 753                        /* select seconds for timer units */
 754                        superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF,
 755                                F71808FG_FLAG_WD_UNIT);
 756                        superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 757                                start_withtimeout);
 758                }
 759
 760                superio_exit(sioaddr);
 761                mutex_unlock(&watchdog.lock);
 762
 763                if (nowayout)
 764                        __module_get(THIS_MODULE);
 765
 766                pr_info("watchdog started with initial timeout of %u sec\n",
 767                        start_withtimeout);
 768        }
 769
 770        return 0;
 771
 772exit_unlock:
 773        mutex_unlock(&watchdog.lock);
 774exit_miscdev:
 775        misc_deregister(&watchdog_miscdev);
 776exit_reboot:
 777        unregister_reboot_notifier(&watchdog_notifier);
 778
 779        return err;
 780}
 781
 782static int __init f71808e_find(int sioaddr)
 783{
 784        u16 devid;
 785        int err = superio_enter(sioaddr);
 786        if (err)
 787                return err;
 788
 789        devid = superio_inw(sioaddr, SIO_REG_MANID);
 790        if (devid != SIO_FINTEK_ID) {
 791                pr_debug("Not a Fintek device\n");
 792                err = -ENODEV;
 793                goto exit;
 794        }
 795
 796        devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
 797        switch (devid) {
 798        case SIO_F71808_ID:
 799                watchdog.type = f71808fg;
 800                break;
 801        case SIO_F71862_ID:
 802                watchdog.type = f71862fg;
 803                err = f71862fg_pin_configure(0); /* validate module parameter */
 804                break;
 805        case SIO_F71868_ID:
 806                watchdog.type = f71868;
 807                break;
 808        case SIO_F71869_ID:
 809        case SIO_F71869A_ID:
 810                watchdog.type = f71869;
 811                break;
 812        case SIO_F71882_ID:
 813                watchdog.type = f71882fg;
 814                break;
 815        case SIO_F71889_ID:
 816                watchdog.type = f71889fg;
 817                break;
 818        case SIO_F71858_ID:
 819                /* Confirmed (by datasheet) not to have a watchdog. */
 820                err = -ENODEV;
 821                goto exit;
 822        case SIO_F81865_ID:
 823                watchdog.type = f81865;
 824                break;
 825        case SIO_F81866_ID:
 826                watchdog.type = f81866;
 827                break;
 828        default:
 829                pr_info("Unrecognized Fintek device: %04x\n",
 830                        (unsigned int)devid);
 831                err = -ENODEV;
 832                goto exit;
 833        }
 834
 835        pr_info("Found %s watchdog chip, revision %d\n",
 836                f71808e_names[watchdog.type],
 837                (int)superio_inb(sioaddr, SIO_REG_DEVREV));
 838exit:
 839        superio_exit(sioaddr);
 840        return err;
 841}
 842
 843static int __init f71808e_init(void)
 844{
 845        static const unsigned short addrs[] = { 0x2e, 0x4e };
 846        int err = -ENODEV;
 847        int i;
 848
 849        for (i = 0; i < ARRAY_SIZE(addrs); i++) {
 850                err = f71808e_find(addrs[i]);
 851                if (err == 0)
 852                        break;
 853        }
 854        if (i == ARRAY_SIZE(addrs))
 855                return err;
 856
 857        return watchdog_init(addrs[i]);
 858}
 859
 860static void __exit f71808e_exit(void)
 861{
 862        if (watchdog_is_running()) {
 863                pr_warn("Watchdog timer still running, stopping it\n");
 864                watchdog_stop();
 865        }
 866        misc_deregister(&watchdog_miscdev);
 867        unregister_reboot_notifier(&watchdog_notifier);
 868}
 869
 870MODULE_DESCRIPTION("F71808E Watchdog Driver");
 871MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>");
 872MODULE_LICENSE("GPL");
 873
 874module_init(f71808e_init);
 875module_exit(f71808e_exit);
 876