drivers/watchdog/f71808e_wdt.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /***************************************************************************
   3  *   Copyright (C) 2006 by Hans Edgington <hans@edgington.nl>              *
   4  *   Copyright (C) 2007-2009 Hans de Goede <hdegoede@redhat.com>           *
   5  *   Copyright (C) 2010 Giel van Schijndel <me@mortis.eu>                  *
   6  *                                                                         *
   7  ***************************************************************************/
   8
   9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
  11 #include <linux/err.h>
  12 #include <linux/fs.h>
  13 #include <linux/init.h>
  14 #include <linux/io.h>
  15 #include <linux/ioport.h>
  16 #include <linux/miscdevice.h>
  17 #include <linux/module.h>
  18 #include <linux/mutex.h>
  19 #include <linux/notifier.h>
  20 #include <linux/reboot.h>
  21 #include <linux/uaccess.h>
  22 #include <linux/watchdog.h>
  23
  24 #define DRVNAME "f71808e_wdt"
  25
  26 #define SIO_F71808FG_LD_WDT     0x07    /* Watchdog timer logical device */
  27 #define SIO_UNLOCK_KEY          0x87    /* Key to enable Super-I/O */
  28 #define SIO_LOCK_KEY            0xAA    /* Key to disable Super-I/O */
  29
  30 #define SIO_REG_LDSEL           0x07    /* Logical device select */
  31 #define SIO_REG_DEVID           0x20    /* Device ID (2 bytes) */
  32 #define SIO_REG_DEVREV          0x22    /* Device revision */
  33 #define SIO_REG_MANID           0x23    /* Fintek ID (2 bytes) */
  34 #define SIO_REG_ROM_ADDR_SEL    0x27    /* ROM address select */
  35 #define SIO_F81866_REG_PORT_SEL 0x27    /* F81866 Multi-Function Register */
  36 #define SIO_REG_MFUNCT1         0x29    /* Multi function select 1 */
  37 #define SIO_REG_MFUNCT2         0x2a    /* Multi function select 2 */
  38 #define SIO_REG_MFUNCT3         0x2b    /* Multi function select 3 */
  39 #define SIO_F81866_REG_GPIO1    0x2c    /* F81866 GPIO1 Enable Register */
  40 #define SIO_REG_ENABLE          0x30    /* Logical device enable */
  41 #define SIO_REG_ADDR            0x60    /* Logical device address (2 bytes) */
  42
  43 #define SIO_FINTEK_ID           0x1934  /* Manufacturers ID */
  44 #define SIO_F71808_ID           0x0901  /* Chipset ID */
  45 #define SIO_F71858_ID           0x0507  /* Chipset ID */
  46 #define SIO_F71862_ID           0x0601  /* Chipset ID */
  47 #define SIO_F71868_ID           0x1106  /* Chipset ID */
  48 #define SIO_F71869_ID           0x0814  /* Chipset ID */
  49 #define SIO_F71869A_ID          0x1007  /* Chipset ID */
  50 #define SIO_F71882_ID           0x0541  /* Chipset ID */
  51 #define SIO_F71889_ID           0x0723  /* Chipset ID */
  52 #define SIO_F81865_ID           0x0704  /* Chipset ID */
  53 #define SIO_F81866_ID           0x1010  /* Chipset ID */
  54
  55 #define F71808FG_REG_WDO_CONF           0xf0
  56 #define F71808FG_REG_WDT_CONF           0xf5
  57 #define F71808FG_REG_WD_TIME            0xf6
  58
  59 #define F71808FG_FLAG_WDOUT_EN          7
  60
  61 #define F71808FG_FLAG_WDTMOUT_STS       6
  62 #define F71808FG_FLAG_WD_EN             5
  63 #define F71808FG_FLAG_WD_PULSE          4
  64 #define F71808FG_FLAG_WD_UNIT           3
  65
  66 #define F81865_REG_WDO_CONF             0xfa
  67 #define F81865_FLAG_WDOUT_EN            0
  68
  69 /* Default values */
  70 #define WATCHDOG_TIMEOUT        60      /* 1 minute default timeout */
  71 #define WATCHDOG_MAX_TIMEOUT    (60 * 255)
  72 #define WATCHDOG_PULSE_WIDTH    125     /* 125 ms, default pulse width for
  73                                            watchdog signal */
  74 #define WATCHDOG_F71862FG_PIN   63      /* default watchdog reset output
  75                                            pin number 63 */
  76
  77 static unsigned short force_id;
  78 module_param(force_id, ushort, 0);
  79 MODULE_PARM_DESC(force_id, "Override the detected device ID");
  80
  81 static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
  82 static int timeout = WATCHDOG_TIMEOUT;  /* default timeout in seconds */
  83 module_param(timeout, int, 0);
  84 MODULE_PARM_DESC(timeout,
  85         "Watchdog timeout in seconds. 1<= timeout <="
  86                         __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
  87                         __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
  88
  89 static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
  90 module_param(pulse_width, uint, 0);
  91 MODULE_PARM_DESC(pulse_width,
  92         "Watchdog signal pulse width. 0(=level), 1, 25, 30, 125, 150, 5000 or 6000 ms"
  93                         " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
  94
  95 static unsigned int f71862fg_pin = WATCHDOG_F71862FG_PIN;
  96 module_param(f71862fg_pin, uint, 0);
  97 MODULE_PARM_DESC(f71862fg_pin,
  98         "Watchdog f71862fg reset output pin configuration. Choose pin 56 or 63"
  99                         " (default=" __MODULE_STRING(WATCHDOG_F71862FG_PIN)")");
 100
 101 static bool nowayout = WATCHDOG_NOWAYOUT;
 102 module_param(nowayout, bool, 0444);
 103 MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
 104
 105 static unsigned int start_withtimeout;
 106 module_param(start_withtimeout, uint, 0);
 107 MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
 108         " given initial timeout. Zero (default) disables this feature.");
 109
 110 enum chips { f71808fg, f71858fg, f71862fg, f71868, f71869, f71882fg, f71889fg,
 111              f81865, f81866};
 112
 113 static const char *f71808e_names[] = {
 114         "f71808fg",
 115         "f71858fg",
 116         "f71862fg",
 117         "f71868",
 118         "f71869",
 119         "f71882fg",
 120         "f71889fg",
 121         "f81865",
 122         "f81866",
 123 };
 124
 125 /* Super-I/O Function prototypes */
 126 static inline int superio_inb(int base, int reg);
 127 static inline int superio_inw(int base, int reg);
 128 static inline void superio_outb(int base, int reg, u8 val);
 129 static inline void superio_set_bit(int base, int reg, int bit);
 130 static inline void superio_clear_bit(int base, int reg, int bit);
 131 static inline int superio_enter(int base);
 132 static inline void superio_select(int base, int ld);
 133 static inline void superio_exit(int base);
 134
 135 struct watchdog_data {
 136         unsigned short  sioaddr;
 137         enum chips      type;
 138         unsigned long   opened;
 139         struct mutex    lock;
 140         char            expect_close;
 141         struct watchdog_info ident;
 142
 143         unsigned short  timeout;
 144         u8              timer_val;      /* content for the wd_time register */
 145         char            minutes_mode;
 146         u8              pulse_val;      /* pulse width flag */
 147         char            pulse_mode;     /* enable pulse output mode? */
 148         char            caused_reboot;  /* last reboot was by the watchdog */
 149 };
 150
 151 static struct watchdog_data watchdog = {
 152         .lock = __MUTEX_INITIALIZER(watchdog.lock),
 153 };
 154
 155 /* Super I/O functions */
 156 static inline int superio_inb(int base, int reg)
 157 {
 158         outb(reg, base);
 159         return inb(base + 1);
 160 }
 161
 162 static int superio_inw(int base, int reg)
 163 {
 164         int val;
 165         val  = superio_inb(base, reg) << 8;
 166         val |= superio_inb(base, reg + 1);
 167         return val;
 168 }
 169
 170 static inline void superio_outb(int base, int reg, u8 val)
 171 {
 172         outb(reg, base);
 173         outb(val, base + 1);
 174 }
 175
 176 static inline void superio_set_bit(int base, int reg, int bit)
 177 {
 178         unsigned long val = superio_inb(base, reg);
 179         __set_bit(bit, &val);
 180         superio_outb(base, reg, val);
 181 }
 182
 183 static inline void superio_clear_bit(int base, int reg, int bit)
 184 {
 185         unsigned long val = superio_inb(base, reg);
 186         __clear_bit(bit, &val);
 187         superio_outb(base, reg, val);
 188 }
 189
 190 static inline int superio_enter(int base)
 191 {
 192         /* Don't step on other drivers' I/O space by accident */
 193         if (!request_muxed_region(base, 2, DRVNAME)) {
 194                 pr_err("I/O address 0x%04x already in use\n", (int)base);
 195                 return -EBUSY;
 196         }
 197
 198         /* according to the datasheet the key must be sent twice! */
 199         outb(SIO_UNLOCK_KEY, base);
 200         outb(SIO_UNLOCK_KEY, base);
 201
 202         return 0;
 203 }
 204
 205 static inline void superio_select(int base, int ld)
 206 {
 207         outb(SIO_REG_LDSEL, base);
 208         outb(ld, base + 1);
 209 }
 210
 211 static inline void superio_exit(int base)
 212 {
 213         outb(SIO_LOCK_KEY, base);
 214         release_region(base, 2);
 215 }
 216
 217 static int watchdog_set_timeout(int timeout)
 218 {
 219         if (timeout <= 0
 220          || timeout >  max_timeout) {
 221                 pr_err("watchdog timeout out of range\n");
 222                 return -EINVAL;
 223         }
 224
 225         mutex_lock(&watchdog.lock);
 226
 227         watchdog.timeout = timeout;
 228         if (timeout > 0xff) {
 229                 watchdog.timer_val = DIV_ROUND_UP(timeout, 60);
 230                 watchdog.minutes_mode = true;
 231         } else {
 232                 watchdog.timer_val = timeout;
 233                 watchdog.minutes_mode = false;
 234         }
 235
 236         mutex_unlock(&watchdog.lock);
 237
 238         return 0;
 239 }
 240
 241 static int watchdog_set_pulse_width(unsigned int pw)
 242 {
 243         int err = 0;
 244         unsigned int t1 = 25, t2 = 125, t3 = 5000;
 245
 246         if (watchdog.type == f71868) {
 247                 t1 = 30;
 248                 t2 = 150;
 249                 t3 = 6000;
 250         }
 251
 252         mutex_lock(&watchdog.lock);
 253
 254         if        (pw <=  1) {
 255                 watchdog.pulse_val = 0;
 256         } else if (pw <= t1) {
 257                 watchdog.pulse_val = 1;
 258         } else if (pw <= t2) {
 259                 watchdog.pulse_val = 2;
 260         } else if (pw <= t3) {
 261                 watchdog.pulse_val = 3;
 262         } else {
 263                 pr_err("pulse width out of range\n");
 264                 err = -EINVAL;
 265                 goto exit_unlock;
 266         }
 267
 268         watchdog.pulse_mode = pw;
 269
 270 exit_unlock:
 271         mutex_unlock(&watchdog.lock);
 272         return err;
 273 }
 274
 275 static int watchdog_keepalive(void)
 276 {
 277         int err = 0;
 278
 279         mutex_lock(&watchdog.lock);
 280         err = superio_enter(watchdog.sioaddr);
 281         if (err)
 282                 goto exit_unlock;
 283         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 284
 285         if (watchdog.minutes_mode)
 286                 /* select minutes for timer units */
 287                 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 288                                 F71808FG_FLAG_WD_UNIT);
 289         else
 290                 /* select seconds for timer units */
 291                 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 292                                 F71808FG_FLAG_WD_UNIT);
 293
 294         /* Set timer value */
 295         superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME,
 296                            watchdog.timer_val);
 297
 298         superio_exit(watchdog.sioaddr);
 299
 300 exit_unlock:
 301         mutex_unlock(&watchdog.lock);
 302         return err;
 303 }
 304
 305 static int f71862fg_pin_configure(unsigned short ioaddr)
 306 {
 307         /* When ioaddr is non-zero the calling function has to take care of
 308            mutex handling and superio preparation! */
 309
 310         if (f71862fg_pin == 63) {
 311                 if (ioaddr) {
 312                         /* SPI must be disabled first to use this pin! */
 313                         superio_clear_bit(ioaddr, SIO_REG_ROM_ADDR_SEL, 6);
 314                         superio_set_bit(ioaddr, SIO_REG_MFUNCT3, 4);
 315                 }
 316         } else if (f71862fg_pin == 56) {
 317                 if (ioaddr)
 318                         superio_set_bit(ioaddr, SIO_REG_MFUNCT1, 1);
 319         } else {
 320                 pr_err("Invalid argument f71862fg_pin=%d\n", f71862fg_pin);
 321                 return -EINVAL;
 322         }
 323         return 0;
 324 }
 325
 326 static int watchdog_start(void)
 327 {
 328         int err;
 329         u8 tmp;
 330
 331         /* Make sure we don't die as soon as the watchdog is enabled below */
 332         err = watchdog_keepalive();
 333         if (err)
 334                 return err;
 335
 336         mutex_lock(&watchdog.lock);
 337         err = superio_enter(watchdog.sioaddr);
 338         if (err)
 339                 goto exit_unlock;
 340         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 341
 342         /* Watchdog pin configuration */
 343         switch (watchdog.type) {
 344         case f71808fg:
 345                 /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
 346                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT2, 3);
 347                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 3);
 348                 break;
 349
 350         case f71862fg:
 351                 err = f71862fg_pin_configure(watchdog.sioaddr);
 352                 if (err)
 353                         goto exit_superio;
 354                 break;
 355
 356         case f71868:
 357         case f71869:
 358                 /* GPIO14 --> WDTRST# */
 359                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 4);
 360                 break;
 361
 362         case f71882fg:
 363                 /* Set pin 56 to WDTRST# */
 364                 superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
 365                 break;
 366
 367         case f71889fg:
 368                 /* set pin 40 to WDTRST# */
 369                 superio_outb(watchdog.sioaddr, SIO_REG_MFUNCT3,
 370                         superio_inb(watchdog.sioaddr, SIO_REG_MFUNCT3) & 0xcf);
 371                 break;
 372
 373         case f81865:
 374                 /* Set pin 70 to WDTRST# */
 375                 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 5);
 376                 break;
 377
 378         case f81866:
 379                 /*
 380                  * GPIO1 Control Register when 27h BIT3:2 = 01 & BIT0 = 0.
 381                  * The PIN 70(GPIO15/WDTRST) is controlled by 2Ch:
 382                  *     BIT5: 0 -> WDTRST#
 383                  *           1 -> GPIO15
 384                  */
 385                 tmp = superio_inb(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL);
 386                 tmp &= ~(BIT(3) | BIT(0));
 387                 tmp |= BIT(2);
 388                 superio_outb(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL, tmp);
 389
 390                 superio_clear_bit(watchdog.sioaddr, SIO_F81866_REG_GPIO1, 5);
 391                 break;
 392
 393         default:
 394                 /*
 395                  * 'default' label to shut up the compiler and catch
 396                  * programmer errors
 397                  */
 398                 err = -ENODEV;
 399                 goto exit_superio;
 400         }
 401
 402         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 403         superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
 404
 405         if (watchdog.type == f81865 || watchdog.type == f81866)
 406                 superio_set_bit(watchdog.sioaddr, F81865_REG_WDO_CONF,
 407                                 F81865_FLAG_WDOUT_EN);
 408         else
 409                 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF,
 410                                 F71808FG_FLAG_WDOUT_EN);
 411
 412         superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 413                         F71808FG_FLAG_WD_EN);
 414
 415         if (watchdog.pulse_mode) {
 416                 /* Select "pulse" output mode with given duration */
 417                 u8 wdt_conf = superio_inb(watchdog.sioaddr,
 418                                 F71808FG_REG_WDT_CONF);
 419
 420                 /* Set WD_PSWIDTH bits (1:0) */
 421                 wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03);
 422                 /* Set WD_PULSE to "pulse" mode */
 423                 wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
 424
 425                 superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 426                                 wdt_conf);
 427         } else {
 428                 /* Select "level" output mode */
 429                 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 430                                 F71808FG_FLAG_WD_PULSE);
 431         }
 432
 433 exit_superio:
 434         superio_exit(watchdog.sioaddr);
 435 exit_unlock:
 436         mutex_unlock(&watchdog.lock);
 437
 438         return err;
 439 }
 440
 441 static int watchdog_stop(void)
 442 {
 443         int err = 0;
 444
 445         mutex_lock(&watchdog.lock);
 446         err = superio_enter(watchdog.sioaddr);
 447         if (err)
 448                 goto exit_unlock;
 449         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 450
 451         superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
 452                         F71808FG_FLAG_WD_EN);
 453
 454         superio_exit(watchdog.sioaddr);
 455
 456 exit_unlock:
 457         mutex_unlock(&watchdog.lock);
 458
 459         return err;
 460 }
 461
 462 static int watchdog_get_status(void)
 463 {
 464         int status = 0;
 465
 466         mutex_lock(&watchdog.lock);
 467         status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0;
 468         mutex_unlock(&watchdog.lock);
 469
 470         return status;
 471 }
 472
 473 static bool watchdog_is_running(void)
 474 {
 475         /*
 476          * if we fail to determine the watchdog's status assume it to be
 477          * running to be on the safe side
 478          */
 479         bool is_running = true;
 480
 481         mutex_lock(&watchdog.lock);
 482         if (superio_enter(watchdog.sioaddr))
 483                 goto exit_unlock;
 484         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 485
 486         is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0))
 487                 && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF)
 488                         & BIT(F71808FG_FLAG_WD_EN));
 489
 490         superio_exit(watchdog.sioaddr);
 491
 492 exit_unlock:
 493         mutex_unlock(&watchdog.lock);
 494         return is_running;
 495 }
 496
 497 /* /dev/watchdog api */
 498
 499 static int watchdog_open(struct inode *inode, struct file *file)
 500 {
 501         int err;
 502
 503         /* If the watchdog is alive we don't need to start it again */
 504         if (test_and_set_bit(0, &watchdog.opened))
 505                 return -EBUSY;
 506
 507         err = watchdog_start();
 508         if (err) {
 509                 clear_bit(0, &watchdog.opened);
 510                 return err;
 511         }
 512
 513         if (nowayout)
 514                 __module_get(THIS_MODULE);
 515
 516         watchdog.expect_close = 0;
 517         return stream_open(inode, file);
 518 }
 519
 520 static int watchdog_release(struct inode *inode, struct file *file)
 521 {
 522         clear_bit(0, &watchdog.opened);
 523
 524         if (!watchdog.expect_close) {
 525                 watchdog_keepalive();
 526                 pr_crit("Unexpected close, not stopping watchdog!\n");
 527         } else if (!nowayout) {
 528                 watchdog_stop();
 529         }
 530         return 0;
 531 }
 532
 533 /*
 534  *      watchdog_write:
 535  *      @file: file handle to the watchdog
 536  *      @buf: buffer to write
 537  *      @count: count of bytes
 538  *      @ppos: pointer to the position to write. No seeks allowed
 539  *
 540  *      A write to a watchdog device is defined as a keepalive signal. Any
 541  *      write of data will do, as we we don't define content meaning.
 542  */
 543
 544 static ssize_t watchdog_write(struct file *file, const char __user *buf,
 545                             size_t count, loff_t *ppos)
 546 {
 547         if (count) {
 548                 if (!nowayout) {
 549                         size_t i;
 550
 551                         /* In case it was set long ago */
 552                         bool expect_close = false;
 553
 554                         for (i = 0; i != count; i++) {
 555                                 char c;
 556                                 if (get_user(c, buf + i))
 557                                         return -EFAULT;
 558                                 if (c == 'V')
 559                                         expect_close = true;
 560                         }
 561
 562                         /* Properly order writes across fork()ed processes */
 563                         mutex_lock(&watchdog.lock);
 564                         watchdog.expect_close = expect_close;
 565                         mutex_unlock(&watchdog.lock);
 566                 }
 567
 568                 /* someone wrote to us, we should restart timer */
 569                 watchdog_keepalive();
 570         }
 571         return count;
 572 }
 573
 574 /*
 575  *      watchdog_ioctl:
 576  *      @inode: inode of the device
 577  *      @file: file handle to the device
 578  *      @cmd: watchdog command
 579  *      @arg: argument pointer
 580  *
 581  *      The watchdog API defines a common set of functions for all watchdogs
 582  *      according to their available features.
 583  */
 584 static long watchdog_ioctl(struct file *file, unsigned int cmd,
 585         unsigned long arg)
 586 {
 587         int status;
 588         int new_options;
 589         int new_timeout;
 590         union {
 591                 struct watchdog_info __user *ident;
 592                 int __user *i;
 593         } uarg;
 594
 595         uarg.i = (int __user *)arg;
 596
 597         switch (cmd) {
 598         case WDIOC_GETSUPPORT:
 599                 return copy_to_user(uarg.ident, &watchdog.ident,
 600                         sizeof(watchdog.ident)) ? -EFAULT : 0;
 601
 602         case WDIOC_GETSTATUS:
 603                 status = watchdog_get_status();
 604                 if (status < 0)
 605                         return status;
 606                 return put_user(status, uarg.i);
 607
 608         case WDIOC_GETBOOTSTATUS:
 609                 return put_user(0, uarg.i);
 610
 611         case WDIOC_SETOPTIONS:
 612                 if (get_user(new_options, uarg.i))
 613                         return -EFAULT;
 614
 615                 if (new_options & WDIOS_DISABLECARD)
 616                         watchdog_stop();
 617
 618                 if (new_options & WDIOS_ENABLECARD)
 619                         return watchdog_start();
 620                 /* fall through */
 621
 622         case WDIOC_KEEPALIVE:
 623                 watchdog_keepalive();
 624                 return 0;
 625
 626         case WDIOC_SETTIMEOUT:
 627                 if (get_user(new_timeout, uarg.i))
 628                         return -EFAULT;
 629
 630                 if (watchdog_set_timeout(new_timeout))
 631                         return -EINVAL;
 632
 633                 watchdog_keepalive();
 634                 /* fall through */
 635
 636         case WDIOC_GETTIMEOUT:
 637                 return put_user(watchdog.timeout, uarg.i);
 638
 639         default:
 640                 return -ENOTTY;
 641
 642         }
 643 }
 644
 645 static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
 646         void *unused)
 647 {
 648         if (code == SYS_DOWN || code == SYS_HALT)
 649                 watchdog_stop();
 650         return NOTIFY_DONE;
 651 }
 652
 653 static const struct file_operations watchdog_fops = {
 654         .owner          = THIS_MODULE,
 655         .llseek         = no_llseek,
 656         .open           = watchdog_open,
 657         .release        = watchdog_release,
 658         .write          = watchdog_write,
 659         .unlocked_ioctl = watchdog_ioctl,
 660 };
 661
 662 static struct miscdevice watchdog_miscdev = {
 663         .minor          = WATCHDOG_MINOR,
 664         .name           = "watchdog",
 665         .fops           = &watchdog_fops,
 666 };
 667
 668 static struct notifier_block watchdog_notifier = {
 669         .notifier_call = watchdog_notify_sys,
 670 };
 671
 672 static int __init watchdog_init(int sioaddr)
 673 {
 674         int wdt_conf, err = 0;
 675
 676         /* No need to lock watchdog.lock here because no entry points
 677          * into the module have been registered yet.
 678          */
 679         watchdog.sioaddr = sioaddr;
 680         watchdog.ident.options = WDIOC_SETTIMEOUT
 681                                 | WDIOF_MAGICCLOSE
 682                                 | WDIOF_KEEPALIVEPING;
 683
 684         snprintf(watchdog.ident.identity,
 685                 sizeof(watchdog.ident.identity), "%s watchdog",
 686                 f71808e_names[watchdog.type]);
 687
 688         err = superio_enter(sioaddr);
 689         if (err)
 690                 return err;
 691         superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 692
 693         wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF);
 694         watchdog.caused_reboot = wdt_conf & BIT(F71808FG_FLAG_WDTMOUT_STS);
 695
 696         superio_exit(sioaddr);
 697
 698         err = watchdog_set_timeout(timeout);
 699         if (err)
 700                 return err;
 701         err = watchdog_set_pulse_width(pulse_width);
 702         if (err)
 703                 return err;
 704
 705         err = register_reboot_notifier(&watchdog_notifier);
 706         if (err)
 707                 return err;
 708
 709         err = misc_register(&watchdog_miscdev);
 710         if (err) {
 711                 pr_err("cannot register miscdev on minor=%d\n",
 712                        watchdog_miscdev.minor);
 713                 goto exit_reboot;
 714         }
 715
 716         if (start_withtimeout) {
 717                 if (start_withtimeout <= 0
 718                  || start_withtimeout >  max_timeout) {
 719                         pr_err("starting timeout out of range\n");
 720                         err = -EINVAL;
 721                         goto exit_miscdev;
 722                 }
 723
 724                 err = watchdog_start();
 725                 if (err) {
 726                         pr_err("cannot start watchdog timer\n");
 727                         goto exit_miscdev;
 728                 }
 729
 730                 mutex_lock(&watchdog.lock);
 731                 err = superio_enter(sioaddr);
 732                 if (err)
 733                         goto exit_unlock;
 734                 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
 735
 736                 if (start_withtimeout > 0xff) {
 737                         /* select minutes for timer units */
 738                         superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF,
 739                                 F71808FG_FLAG_WD_UNIT);
 740                         superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 741                                 DIV_ROUND_UP(start_withtimeout, 60));
 742                 } else {
 743                         /* select seconds for timer units */
 744                         superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF,
 745                                 F71808FG_FLAG_WD_UNIT);
 746                         superio_outb(sioaddr, F71808FG_REG_WD_TIME,
 747                                 start_withtimeout);
 748                 }
 749
 750                 superio_exit(sioaddr);
 751                 mutex_unlock(&watchdog.lock);
 752
 753                 if (nowayout)
 754                         __module_get(THIS_MODULE);
 755
 756                 pr_info("watchdog started with initial timeout of %u sec\n",
 757                         start_withtimeout);
 758         }
 759
 760         return 0;
 761
 762 exit_unlock:
 763         mutex_unlock(&watchdog.lock);
 764 exit_miscdev:
 765         misc_deregister(&watchdog_miscdev);
 766 exit_reboot:
 767         unregister_reboot_notifier(&watchdog_notifier);
 768
 769         return err;
 770 }
 771
 772 static int __init f71808e_find(int sioaddr)
 773 {
 774         u16 devid;
 775         int err = superio_enter(sioaddr);
 776         if (err)
 777                 return err;
 778
 779         devid = superio_inw(sioaddr, SIO_REG_MANID);
 780         if (devid != SIO_FINTEK_ID) {
 781                 pr_debug("Not a Fintek device\n");
 782                 err = -ENODEV;
 783                 goto exit;
 784         }
 785
 786         devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
 787         switch (devid) {
 788         case SIO_F71808_ID:
 789                 watchdog.type = f71808fg;
 790                 break;
 791         case SIO_F71862_ID:
 792                 watchdog.type = f71862fg;
 793                 err = f71862fg_pin_configure(0); /* validate module parameter */
 794                 break;
 795         case SIO_F71868_ID:
 796                 watchdog.type = f71868;
 797                 break;
 798         case SIO_F71869_ID:
 799         case SIO_F71869A_ID:
 800                 watchdog.type = f71869;
 801                 break;
 802         case SIO_F71882_ID:
 803                 watchdog.type = f71882fg;
 804                 break;
 805         case SIO_F71889_ID:
 806                 watchdog.type = f71889fg;
 807                 break;
 808         case SIO_F71858_ID:
 809                 /* Confirmed (by datasheet) not to have a watchdog. */
 810                 err = -ENODEV;
 811                 goto exit;
 812         case SIO_F81865_ID:
 813                 watchdog.type = f81865;
 814                 break;
 815         case SIO_F81866_ID:
 816                 watchdog.type = f81866;
 817                 break;
 818         default:
 819                 pr_info("Unrecognized Fintek device: %04x\n",
 820                         (unsigned int)devid);
 821                 err = -ENODEV;
 822                 goto exit;
 823         }
 824
 825         pr_info("Found %s watchdog chip, revision %d\n",
 826                 f71808e_names[watchdog.type],
 827                 (int)superio_inb(sioaddr, SIO_REG_DEVREV));
 828 exit:
 829         superio_exit(sioaddr);
 830         return err;
 831 }
 832
 833 static int __init f71808e_init(void)
 834 {
 835         static const unsigned short addrs[] = { 0x2e, 0x4e };
 836         int err = -ENODEV;
 837         int i;
 838
 839         for (i = 0; i < ARRAY_SIZE(addrs); i++) {
 840                 err = f71808e_find(addrs[i]);
 841                 if (err == 0)
 842                         break;
 843         }
 844         if (i == ARRAY_SIZE(addrs))
 845                 return err;
 846
 847         return watchdog_init(addrs[i]);
 848 }
 849
 850 static void __exit f71808e_exit(void)
 851 {
 852         if (watchdog_is_running()) {
 853                 pr_warn("Watchdog timer still running, stopping it\n");
 854                 watchdog_stop();
 855         }
 856         misc_deregister(&watchdog_miscdev);
 857         unregister_reboot_notifier(&watchdog_notifier);
 858 }
 859
 860 MODULE_DESCRIPTION("F71808E Watchdog Driver");
 861 MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>");
 862 MODULE_LICENSE("GPL");
 863
 864 module_init(f71808e_init);
 865 module_exit(f71808e_exit);