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 #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_REG_MFUNCT1         0x29    /* Multi function select 1 */
  49 #define SIO_REG_MFUNCT2         0x2a    /* Multi function select 2 */
  50 #define SIO_REG_MFUNCT3         0x2b    /* Multi function select 3 */
  51 #define SIO_REG_ENABLE          0x30    /* Logical device enable */
  52 #define SIO_REG_ADDR            0x60    /* Logical device address (2 bytes) */
  53
  54 #define SIO_FINTEK_ID           0x1934  /* Manufacturers ID */
  55 #define SIO_F71808_ID           0x0901  /* Chipset ID */
  56 #define SIO_F71858_ID           0x0507  /* Chipset ID */
  57 #define SIO_F71862_ID           0x0601  /* Chipset ID */
  58 #define SIO_F71869_ID           0x0814  /* Chipset ID */
  59 #define SIO_F71869A_ID          0x1007  /* Chipset ID */
  60 #define SIO_F71882_ID           0x0541  /* Chipset ID */
  61 #define SIO_F71889_ID           0x0723  /* Chipset ID */
  62 #define SIO_F81865_ID           0x0704  /* Chipset ID */
  63
  64 #define F71808FG_REG_WDO_CONF           0xf0
  65 #define F71808FG_REG_WDT_CONF           0xf5
  66 #define F71808FG_REG_WD_TIME            0xf6
  67
  68 #define F71808FG_FLAG_WDOUT_EN          7
  69
  70 #define F71808FG_FLAG_WDTMOUT_STS       6
  71 #define F71808FG_FLAG_WD_EN             5
  72 #define F71808FG_FLAG_WD_PULSE          4
  73 #define F71808FG_FLAG_WD_UNIT           3
  74
  75 #define F81865_REG_WDO_CONF             0xfa
  76 #define F81865_FLAG_WDOUT_EN            0
  77
  78 /* Default values */
  79 #define WATCHDOG_TIMEOUT        60      /* 1 minute default timeout */
  80 #define WATCHDOG_MAX_TIMEOUT    (60 * 255)
  81 #define WATCHDOG_PULSE_WIDTH    125     /* 125 ms, default pulse width for
  82                                            watchdog signal */
  83 #define WATCHDOG_F71862FG_PIN   63      /* default watchdog reset output
  84                                            pin number 63 */
  85
  86 static unsigned short force_id;
  87 module_param(force_id, ushort, 0);
  88 MODULE_PARM_DESC(force_id, "Override the detected device ID");
  89
  90 static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
  91 static int timeout = WATCHDOG_TIMEOUT;  /* default timeout in seconds */
  92 module_param(timeout, int, 0);
  93 MODULE_PARM_DESC(timeout,
  94         "Watchdog timeout in seconds. 1<= timeout <="
  95                         __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
  96                         __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
  97
  98 static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
  99 module_param(pulse_width, uint, 0);
 100 MODULE_PARM_DESC(pulse_width,
 101         "Watchdog signal pulse width. 0(=level), 1 ms, 25 ms, 125 ms or 5000 ms"
 102                         " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
 103
 104 static unsigned int f71862fg_pin = WATCHDOG_F71862FG_PIN;
 105 module_param(f71862fg_pin, uint, 0);
 106 MODULE_PARM_DESC(f71862fg_pin,
 107         "Watchdog f71862fg reset output pin configuration. Choose pin 56 or 63"
 108                         " (default=" __MODULE_STRING(WATCHDOG_F71862FG_PIN)")");
 109
 110 static bool nowayout = WATCHDOG_NOWAYOUT;
 111 module_param(nowayout, bool, 0444);
 112 MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
 113
 114 static unsigned int start_withtimeout;
 115 module_param(start_withtimeout, uint, 0);
 116 MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
 117         " given initial timeout. Zero (default) disables this feature.");
 118
 119 enum chips { f71808fg, f71858fg, f71862fg, f71869, f71882fg, f71889fg, f81865 };
 120
 121 static const char *f71808e_names[] = {
 122         "f71808fg",
 123         "f71858fg",
 124         "f71862fg",
 125         "f71869",
 126         "f71882fg",
 127         "f71889fg",
 128         "f81865",
 129 };
 130
 131 /* Super-I/O Function prototypes */
 132 static inline int superio_inb(int base, int reg);
 133 static inline int superio_inw(int base, int reg);
 134 static inline void superio_outb(int base, int reg, u8 val);
 135 static inline void superio_set_bit(int base, int reg, int bit);
 136 static inline void superio_clear_bit(int base, int reg, int bit);
 137 static inline int superio_enter(int base);
 138 static inline void superio_select(int base, int ld);
 139 static inline void superio_exit(int base);
 140
 141 struct watchdog_data {
 142         unsigned short  sioaddr;
 143         enum chips      type;
 144         unsigned long   opened;
 145         struct mutex    lock;
 146         char            expect_close;
 147         struct watchdog_info ident;
 148
 149         unsigned short  timeout;
 150         u8              timer_val;      /* content for the wd_time register */
 151         char            minutes_mode;
 152         u8              pulse_val;      /* pulse width flag */
 153         char            pulse_mode;     /* enable pulse output mode? */
 154         char            caused_reboot;  /* last reboot was by the watchdog */
 155 };
 156
 157 static struct watchdog_data watchdog = {
 158         .lock = __MUTEX_INITIALIZER(watchdog.lock),
 159 };
 160
 161 /* Super I/O functions */
 162 static inline int superio_inb(int base, int reg)
 163 {
 164         outb(reg, base);
 165         return inb(base + 1);
 166 }
 167
 168 static int superio_inw(int base, int reg)
 169 {
 170         int val;
 171         val  = superio_inb(base, reg) << 8;
 172         val |= superio_inb(base, reg + 1);
 173         return val;
 174 }
 175
 176 static inline void superio_outb(int base, int reg, u8 val)
 177 {
 178         outb(reg, base);
 179         outb(val, base + 1);
 180 }
 181
 182 static inline void superio_set_bit(int base, int reg, int bit)
 183 {
 184         unsigned long val = superio_inb(base, reg);
 185         __set_bit(bit, &val);
 186         superio_outb(base, reg, val);
 187 }
 188
 189 static inline void superio_clear_bit(int base, int reg, int bit)
 190 {
 191         unsigned long val = superio_inb(base, reg);
 192         __clear_bit(bit, &val);
 193         superio_outb(base, reg, val);
 194 }
 195
 196 static inline int superio_enter(int base)
 197 {
 198         /* Don't step on other drivers' I/O space by accident */
 199         if (!request_muxed_region(base, 2, DRVNAME)) {
 200                 pr_err("I/O address 0x%04x already in use\n", (int)base);
 201                 return -EBUSY;
 202         }
 203
 204         /* according to the datasheet the key must be sent twice! */
 205         outb(SIO_UNLOCK_KEY, base);
 206         outb(SIO_UNLOCK_KEY, base);
 207
 208         return 0;
 209 }
 210
 211 static inline void superio_select(int base, int ld)
 212 {
 213         outb(SIO_REG_LDSEL, base);
 214         outb(ld, base + 1);
 215 }
 216
 217 static inline void superio_exit(int base)
 218 {
 219         outb(SIO_LOCK_KEY, base);
 220         release_region(base, 2);
 221 }
 222
 223 static int watchdog_set_timeout(int timeout)
 224 {
 225         if (timeout <= 0
 226          || timeout >  max_timeout) {
 227                 pr_err("watchdog timeout out of range\n");
 228                 return -EINVAL;
 229         }
 230
 231         mutex_lock(&watchdog.lock);
 232
 233         watchdog.timeout = timeout;
 234         if (timeout > 0xff) {
 235                 watchdog.timer_val = DIV_ROUND_UP(timeout, 60);
 236                 watchdog.minutes_mode = true;
 237         } else {
 238                 watchdog.timer_val = timeout;
 239                 watchdog.minutes_mode = false;
 240         }
 241
 242         mutex_unlock(&watchdog.lock);
 243
 244         return 0;
 245 }
 246
 247 static int watchdog_set_pulse_width(unsigned int pw)
 248 {
 249         int err = 0;
 250
 251         mutex_lock(&watchdog.lock);
 252
 253         if        (pw <=    1) {
 254                 watchdog.pulse_val = 0;
 255         } else if (pw <=   25) {
 256                 watchdog.pulse_val = 1;
 257         } else if (pw <=  125) {
 258                 watchdog.pulse_val = 2;
 259         } else if (pw <= 5000) {
 260                 watchdog.pulse_val = 3;
 261         } else {
 262                 pr_err("pulse width out of range\n");
 263                 err = -EINVAL;
 264                 goto exit_unlock;
 265         }
 266
 267         watchdog.pulse_mode = pw;
 268
 269 exit_unlock:
 270         mutex_unlock(&watchdog.lock);
 271         return err;
 272 }
 273
 274 static int watchdog_keepalive(void)
 275 {
 276         int err = 0;
 277
 278         mutex_lock(&watchdog.lock);
 279         err = superio_enter(watchdog.sioaddr);
 280         if (err)
 281                 goto exit_unlock;
 282         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 283
 284         if (watchdog.minutes_mode)
 285                 /* select minutes for timer units */
 286                 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 287                                 F71808FG_FLAG_WD_UNIT);
 288         else
 289                 /* select seconds for timer units */
 290                 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 291                                 F71808FG_FLAG_WD_UNIT);
 292
 293         /* Set timer value */
 294         superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME,
 295                            watchdog.timer_val);
 296
 297         superio_exit(watchdog.sioaddr);
 298
 299 exit_unlock:
 300         mutex_unlock(&watchdog.lock);
 301         return err;
 302 }
 303
 304 static int f71862fg_pin_configure(unsigned short ioaddr)
 305 {
 306         /* When ioaddr is non-zero the calling function has to take care of
 307            mutex handling and superio preparation! */
 308
 309         if (f71862fg_pin == 63) {
 310                 if (ioaddr) {
 311                         /* SPI must be disabled first to use this pin! */
 312                         superio_clear_bit(ioaddr, SIO_REG_ROM_ADDR_SEL, 6);
 313                         superio_set_bit(ioaddr, SIO_REG_MFUNCT3, 4);
 314                 }
 315         } else if (f71862fg_pin == 56) {
 316                 if (ioaddr)
 317                         superio_set_bit(ioaddr, SIO_REG_MFUNCT1, 1);
 318         } else {
 319                 pr_err("Invalid argument f71862fg_pin=%d\n", f71862fg_pin);
 320                 return -EINVAL;
 321         }
 322         return 0;
 323 }
 324
 325 static int watchdog_start(void)
 326 {
 327         /* Make sure we don't die as soon as the watchdog is enabled below */
 328         int err = watchdog_keepalive();
 329         if (err)
 330                 return err;
 331
 332         mutex_lock(&watchdog.lock);
 333         err = superio_enter(watchdog.sioaddr);
 334         if (err)
 335                 goto exit_unlock;
 336         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 337
 338         /* Watchdog pin configuration */
 339         switch (watchdog.type) {
 340         case f71808fg:
 341                 /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
 342                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT2, 3);
 343                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 3);
 344                 break;
 345
 346         case f71862fg:
 347                 err = f71862fg_pin_configure(watchdog.sioaddr);
 348                 if (err)
 349                         goto exit_superio;
 350                 break;
 351
 352         case f71869:
 353                 /* GPIO14 --> WDTRST# */
 354                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 4);
 355                 break;
 356
 357         case f71882fg:
 358                 /* Set pin 56 to WDTRST# */
 359                 superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
 360                 break;
 361
 362         case f71889fg:
 363                 /* set pin 40 to WDTRST# */
 364                 superio_outb(watchdog.sioaddr, SIO_REG_MFUNCT3,
 365                         superio_inb(watchdog.sioaddr, SIO_REG_MFUNCT3) & 0xcf);
 366                 break;
 367
 368         case f81865:
 369                 /* Set pin 70 to WDTRST# */
 370                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 5);
 371                 break;
 372
 373         default:
 374                 /*
 375                  * 'default' label to shut up the compiler and catch
 376                  * programmer errors
 377                  */
 378                 err = -ENODEV;
 379                 goto exit_superio;
 380         }
 381
 382         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 383         superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
 384
 385         if (watchdog.type == f81865)
 386                 superio_set_bit(watchdog.sioaddr, F81865_REG_WDO_CONF,
 387                                 F81865_FLAG_WDOUT_EN);
 388         else
 389                 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF,
 390                                 F71808FG_FLAG_WDOUT_EN);
 391
 392         superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 393                         F71808FG_FLAG_WD_EN);
 394
 395         if (watchdog.pulse_mode) {
 396                 /* Select "pulse" output mode with given duration */
 397                 u8 wdt_conf = superio_inb(watchdog.sioaddr,
 398                                 F71808FG_REG_WDT_CONF);
 399
 400                 /* Set WD_PSWIDTH bits (1:0) */
 401                 wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03);
 402                 /* Set WD_PULSE to "pulse" mode */
 403                 wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
 404
 405                 superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 406                                 wdt_conf);
 407         } else {
 408                 /* Select "level" output mode */
 409                 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 410                                 F71808FG_FLAG_WD_PULSE);
 411         }
 412
 413 exit_superio:
 414         superio_exit(watchdog.sioaddr);
 415 exit_unlock:
 416         mutex_unlock(&watchdog.lock);
 417
 418         return err;
 419 }
 420
 421 static int watchdog_stop(void)
 422 {
 423         int err = 0;
 424
 425         mutex_lock(&watchdog.lock);
 426         err = superio_enter(watchdog.sioaddr);
 427         if (err)
 428                 goto exit_unlock;
 429         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 430
 431         superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 432                         F71808FG_FLAG_WD_EN);
 433
 434         superio_exit(watchdog.sioaddr);
 435
 436 exit_unlock:
 437         mutex_unlock(&watchdog.lock);
 438
 439         return err;
 440 }
 441
 442 static int watchdog_get_status(void)
 443 {
 444         int status = 0;
 445
 446         mutex_lock(&watchdog.lock);
 447         status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0;
 448         mutex_unlock(&watchdog.lock);
 449
 450         return status;
 451 }
 452
 453 static bool watchdog_is_running(void)
 454 {
 455         /*
 456          * if we fail to determine the watchdog's status assume it to be
 457          * running to be on the safe side
 458          */
 459         bool is_running = true;
 460
 461         mutex_lock(&watchdog.lock);
 462         if (superio_enter(watchdog.sioaddr))
 463                 goto exit_unlock;
 464         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 465
 466         is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0))
 467                 && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF)
 468                         & F71808FG_FLAG_WD_EN);
 469
 470         superio_exit(watchdog.sioaddr);
 471
 472 exit_unlock:
 473         mutex_unlock(&watchdog.lock);
 474         return is_running;
 475 }
 476
 477 /* /dev/watchdog api */
 478
 479 static int watchdog_open(struct inode *inode, struct file *file)
 480 {
 481         int err;
 482
 483         /* If the watchdog is alive we don't need to start it again */
 484         if (test_and_set_bit(0, &watchdog.opened))
 485                 return -EBUSY;
 486
 487         err = watchdog_start();
 488         if (err) {
 489                 clear_bit(0, &watchdog.opened);
 490                 return err;
 491         }
 492
 493         if (nowayout)
 494                 __module_get(THIS_MODULE);
 495
 496         watchdog.expect_close = 0;
 497         return nonseekable_open(inode, file);
 498 }
 499
 500 static int watchdog_release(struct inode *inode, struct file *file)
 501 {
 502         clear_bit(0, &watchdog.opened);
 503
 504         if (!watchdog.expect_close) {
 505                 watchdog_keepalive();
 506                 pr_crit("Unexpected close, not stopping watchdog!\n");
 507         } else if (!nowayout) {
 508                 watchdog_stop();
 509         }
 510         return 0;
 511 }
 512
 513 /*
 514  *      watchdog_write:
 515  *      @file: file handle to the watchdog
 516  *      @buf: buffer to write
 517  *      @count: count of bytes
 518  *      @ppos: pointer to the position to write. No seeks allowed
 519  *
 520  *      A write to a watchdog device is defined as a keepalive signal. Any
 521  *      write of data will do, as we we don't define content meaning.
 522  */
 523
 524 static ssize_t watchdog_write(struct file *file, const char __user *buf,
 525                             size_t count, loff_t *ppos)
 526 {
 527         if (count) {
 528                 if (!nowayout) {
 529                         size_t i;
 530
 531                         /* In case it was set long ago */
 532                         bool expect_close = false;
 533
 534                         for (i = 0; i != count; i++) {
 535                                 char c;
 536                                 if (get_user(c, buf + i))
 537                                         return -EFAULT;
 538                                 expect_close = (c == 'V');
 539                         }
 540
 541                         /* Properly order writes across fork()ed processes */
 542                         mutex_lock(&watchdog.lock);
 543                         watchdog.expect_close = expect_close;
 544                         mutex_unlock(&watchdog.lock);
 545                 }
 546
 547                 /* someone wrote to us, we should restart timer */
 548                 watchdog_keepalive();
 549         }
 550         return count;
 551 }
 552
 553 /*
 554  *      watchdog_ioctl:
 555  *      @inode: inode of the device
 556  *      @file: file handle to the device
 557  *      @cmd: watchdog command
 558  *      @arg: argument pointer
 559  *
 560  *      The watchdog API defines a common set of functions for all watchdogs
 561  *      according to their available features.
 562  */
 563 static long watchdog_ioctl(struct file *file, unsigned int cmd,
 564         unsigned long arg)
 565 {
 566         int status;
 567         int new_options;
 568         int new_timeout;
 569         union {
 570                 struct watchdog_info __user *ident;
 571                 int __user *i;
 572         } uarg;
 573
 574         uarg.i = (int __user *)arg;
 575
 576         switch (cmd) {
 577         case WDIOC_GETSUPPORT:
 578                 return copy_to_user(uarg.ident, &watchdog.ident,
 579                         sizeof(watchdog.ident)) ? -EFAULT : 0;
 580
 581         case WDIOC_GETSTATUS:
 582                 status = watchdog_get_status();
 583                 if (status < 0)
 584                         return status;
 585                 return put_user(status, uarg.i);
 586
 587         case WDIOC_GETBOOTSTATUS:
 588                 return put_user(0, uarg.i);
 589
 590         case WDIOC_SETOPTIONS:
 591                 if (get_user(new_options, uarg.i))
 592                         return -EFAULT;
 593
 594                 if (new_options & WDIOS_DISABLECARD)
 595                         watchdog_stop();
 596
 597                 if (new_options & WDIOS_ENABLECARD)
 598                         return watchdog_start();
 599
 600
 601         case WDIOC_KEEPALIVE:
 602                 watchdog_keepalive();
 603                 return 0;
 604
 605         case WDIOC_SETTIMEOUT:
 606                 if (get_user(new_timeout, uarg.i))
 607                         return -EFAULT;
 608
 609                 if (watchdog_set_timeout(new_timeout))
 610                         return -EINVAL;
 611
 612                 watchdog_keepalive();
 613                 /* Fall */
 614
 615         case WDIOC_GETTIMEOUT:
 616                 return put_user(watchdog.timeout, uarg.i);
 617
 618         default:
 619                 return -ENOTTY;
 620
 621         }
 622 }
 623
 624 static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
 625         void *unused)
 626 {
 627         if (code == SYS_DOWN || code == SYS_HALT)
 628                 watchdog_stop();
 629         return NOTIFY_DONE;
 630 }
 631
 632 static const struct file_operations watchdog_fops = {
 633         .owner          = THIS_MODULE,
 634         .llseek         = no_llseek,
 635         .open           = watchdog_open,
 636         .release        = watchdog_release,
 637         .write          = watchdog_write,
 638         .unlocked_ioctl = watchdog_ioctl,
 639 };
 640
 641 static struct miscdevice watchdog_miscdev = {
 642         .minor          = WATCHDOG_MINOR,
 643         .name           = "watchdog",
 644         .fops           = &watchdog_fops,
 645 };
 646
 647 static struct notifier_block watchdog_notifier = {
 648         .notifier_call = watchdog_notify_sys,
 649 };
 650
 651 static int __init watchdog_init(int sioaddr)
 652 {
 653         int wdt_conf, err = 0;
 654
 655         /* No need to lock watchdog.lock here because no entry points
 656          * into the module have been registered yet.
 657          */
 658         watchdog.sioaddr = sioaddr;
 659         watchdog.ident.options = WDIOC_SETTIMEOUT
 660                                 | WDIOF_MAGICCLOSE
 661                                 | WDIOF_KEEPALIVEPING;
 662
 663         snprintf(watchdog.ident.identity,
 664                 sizeof(watchdog.ident.identity), "%s watchdog",
 665                 f71808e_names[watchdog.type]);
 666
 667         err = superio_enter(sioaddr);
 668         if (err)
 669                 return err;
 670         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 671
 672         wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF);
 673         watchdog.caused_reboot = wdt_conf & BIT(F71808FG_FLAG_WDTMOUT_STS);
 674
 675         superio_exit(sioaddr);
 676
 677         err = watchdog_set_timeout(timeout);
 678         if (err)
 679                 return err;
 680         err = watchdog_set_pulse_width(pulse_width);
 681         if (err)
 682                 return err;
 683
 684         err = register_reboot_notifier(&watchdog_notifier);
 685         if (err)
 686                 return err;
 687
 688         err = misc_register(&watchdog_miscdev);
 689         if (err) {
 690                 pr_err("cannot register miscdev on minor=%d\n",
 691                        watchdog_miscdev.minor);
 692                 goto exit_reboot;
 693         }
 694
 695         if (start_withtimeout) {
 696                 if (start_withtimeout <= 0
 697                  || start_withtimeout >  max_timeout) {
 698                         pr_err("starting timeout out of range\n");
 699                         err = -EINVAL;
 700                         goto exit_miscdev;
 701                 }
 702
 703                 err = watchdog_start();
 704                 if (err) {
 705                         pr_err("cannot start watchdog timer\n");
 706                         goto exit_miscdev;
 707                 }
 708
 709                 mutex_lock(&watchdog.lock);
 710                 err = superio_enter(sioaddr);
 711                 if (err)
 712                         goto exit_unlock;
 713                 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 714
 715                 if (start_withtimeout > 0xff) {
 716                         /* select minutes for timer units */
 717                         superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF,
 718                                 F71808FG_FLAG_WD_UNIT);
 719                         superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 720                                 DIV_ROUND_UP(start_withtimeout, 60));
 721                 } else {
 722                         /* select seconds for timer units */
 723                         superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF,
 724                                 F71808FG_FLAG_WD_UNIT);
 725                         superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 726                                 start_withtimeout);
 727                 }
 728
 729                 superio_exit(sioaddr);
 730                 mutex_unlock(&watchdog.lock);
 731
 732                 if (nowayout)
 733                         __module_get(THIS_MODULE);
 734
 735                 pr_info("watchdog started with initial timeout of %u sec\n",
 736                         start_withtimeout);
 737         }
 738
 739         return 0;
 740
 741 exit_unlock:
 742         mutex_unlock(&watchdog.lock);
 743 exit_miscdev:
 744         misc_deregister(&watchdog_miscdev);
 745 exit_reboot:
 746         unregister_reboot_notifier(&watchdog_notifier);
 747
 748         return err;
 749 }
 750
 751 static int __init f71808e_find(int sioaddr)
 752 {
 753         u16 devid;
 754         int err = superio_enter(sioaddr);
 755         if (err)
 756                 return err;
 757
 758         devid = superio_inw(sioaddr, SIO_REG_MANID);
 759         if (devid != SIO_FINTEK_ID) {
 760                 pr_debug("Not a Fintek device\n");
 761                 err = -ENODEV;
 762                 goto exit;
 763         }
 764
 765         devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
 766         switch (devid) {
 767         case SIO_F71808_ID:
 768                 watchdog.type = f71808fg;
 769                 break;
 770         case SIO_F71862_ID:
 771                 watchdog.type = f71862fg;
 772                 err = f71862fg_pin_configure(0); /* validate module parameter */
 773                 break;
 774         case SIO_F71869_ID:
 775         case SIO_F71869A_ID:
 776                 watchdog.type = f71869;
 777                 break;
 778         case SIO_F71882_ID:
 779                 watchdog.type = f71882fg;
 780                 break;
 781         case SIO_F71889_ID:
 782                 watchdog.type = f71889fg;
 783                 break;
 784         case SIO_F71858_ID:
 785                 /* Confirmed (by datasheet) not to have a watchdog. */
 786                 err = -ENODEV;
 787                 goto exit;
 788         case SIO_F81865_ID:
 789                 watchdog.type = f81865;
 790                 break;
 791         default:
 792                 pr_info("Unrecognized Fintek device: %04x\n",
 793                         (unsigned int)devid);
 794                 err = -ENODEV;
 795                 goto exit;
 796         }
 797
 798         pr_info("Found %s watchdog chip, revision %d\n",
 799                 f71808e_names[watchdog.type],
 800                 (int)superio_inb(sioaddr, SIO_REG_DEVREV));
 801 exit:
 802         superio_exit(sioaddr);
 803         return err;
 804 }
 805
 806 static int __init f71808e_init(void)
 807 {
 808         static const unsigned short addrs[] = { 0x2e, 0x4e };
 809         int err = -ENODEV;
 810         int i;
 811
 812         for (i = 0; i < ARRAY_SIZE(addrs); i++) {
 813                 err = f71808e_find(addrs[i]);
 814                 if (err == 0)
 815                         break;
 816         }
 817         if (i == ARRAY_SIZE(addrs))
 818                 return err;
 819
 820         return watchdog_init(addrs[i]);
 821 }
 822
 823 static void __exit f71808e_exit(void)
 824 {
 825         if (watchdog_is_running()) {
 826                 pr_warn("Watchdog timer still running, stopping it\n");
 827                 watchdog_stop();
 828         }
 829         misc_deregister(&watchdog_miscdev);
 830         unregister_reboot_notifier(&watchdog_notifier);
 831 }
 832
 833 MODULE_DESCRIPTION("F71808E Watchdog Driver");
 834 MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>");
 835 MODULE_LICENSE("GPL");
 836
 837 module_init(f71808e_init);
 838 module_exit(f71808e_exit);