drivers/watchdog/w83627hf_wdt.c

   1 /*
   2  *      w83627hf/thf WDT driver
   3  *
   4  *      (c) Copyright 2013 Guenter Roeck
   5  *              converted to watchdog infrastructure
   6  *
   7  *      (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
   8  *              added support for W83627THF.
   9  *
  10  *      (c) Copyright 2003,2007 Pádraig Brady <P@draigBrady.com>
  11  *
  12  *      Based on advantechwdt.c which is based on wdt.c.
  13  *      Original copyright messages:
  14  *
  15  *      (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
  16  *
  17  *      (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
  18  *                                              All Rights Reserved.
  19  *
  20  *      This program is free software; you can redistribute it and/or
  21  *      modify it under the terms of the GNU General Public License
  22  *      as published by the Free Software Foundation; either version
  23  *      2 of the License, or (at your option) any later version.
  24  *
  25  *      Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
  26  *      warranty for any of this software. This material is provided
  27  *      "AS-IS" and at no charge.
  28  *
  29  *      (c) Copyright 1995    Alan Cox <alan@lxorguk.ukuu.org.uk>
  30  */
  31
  32 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  33
  34 #include <linux/module.h>
  35 #include <linux/moduleparam.h>
  36 #include <linux/types.h>
  37 #include <linux/watchdog.h>
  38 #include <linux/ioport.h>
  39 #include <linux/init.h>
  40 #include <linux/io.h>
  41
  42 #define WATCHDOG_NAME "w83627hf/thf/hg/dhg WDT"
  43 #define WATCHDOG_TIMEOUT 60             /* 60 sec default timeout */
  44
  45 static int wdt_io;
  46 static int cr_wdt_timeout;      /* WDT timeout register */
  47 static int cr_wdt_control;      /* WDT control register */
  48 static int cr_wdt_csr;          /* WDT control & status register */
  49
  50 enum chips { w83627hf, w83627s, w83697hf, w83697ug, w83637hf, w83627thf,
  51              w83687thf, w83627ehf, w83627dhg, w83627uhg, w83667hg, w83627dhg_p,
  52              w83667hg_b, nct6775, nct6776, nct6779, nct6791, nct6792, nct6102 };
  53
  54 static int timeout;                     /* in seconds */
  55 module_param(timeout, int, 0);
  56 MODULE_PARM_DESC(timeout,
  57                 "Watchdog timeout in seconds. 1 <= timeout <= 255, default="
  58                                 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
  59
  60 static bool nowayout = WATCHDOG_NOWAYOUT;
  61 module_param(nowayout, bool, 0);
  62 MODULE_PARM_DESC(nowayout,
  63                 "Watchdog cannot be stopped once started (default="
  64                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
  65
  66 static int early_disable;
  67 module_param(early_disable, int, 0);
  68 MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");
  69
  70 /*
  71  *      Kernel methods.
  72  */
  73
  74 #define WDT_EFER (wdt_io+0)   /* Extended Function Enable Registers */
  75 #define WDT_EFIR (wdt_io+0)   /* Extended Function Index Register
  76                                                         (same as EFER) */
  77 #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
  78
  79 #define W83627HF_LD_WDT         0x08
  80
  81 #define W83627HF_ID             0x52
  82 #define W83627S_ID              0x59
  83 #define W83697HF_ID             0x60
  84 #define W83697UG_ID             0x68
  85 #define W83637HF_ID             0x70
  86 #define W83627THF_ID            0x82
  87 #define W83687THF_ID            0x85
  88 #define W83627EHF_ID            0x88
  89 #define W83627DHG_ID            0xa0
  90 #define W83627UHG_ID            0xa2
  91 #define W83667HG_ID             0xa5
  92 #define W83627DHG_P_ID          0xb0
  93 #define W83667HG_B_ID           0xb3
  94 #define NCT6775_ID              0xb4
  95 #define NCT6776_ID              0xc3
  96 #define NCT6102_ID              0xc4
  97 #define NCT6779_ID              0xc5
  98 #define NCT6791_ID              0xc8
  99 #define NCT6792_ID              0xc9
 100
 101 #define W83627HF_WDT_TIMEOUT    0xf6
 102 #define W83697HF_WDT_TIMEOUT    0xf4
 103 #define NCT6102D_WDT_TIMEOUT    0xf1
 104
 105 #define W83627HF_WDT_CONTROL    0xf5
 106 #define W83697HF_WDT_CONTROL    0xf3
 107 #define NCT6102D_WDT_CONTROL    0xf0
 108
 109 #define W836X7HF_WDT_CSR        0xf7
 110 #define NCT6102D_WDT_CSR        0xf2
 111
 112 static void superio_outb(int reg, int val)
 113 {
 114         outb(reg, WDT_EFER);
 115         outb(val, WDT_EFDR);
 116 }
 117
 118 static inline int superio_inb(int reg)
 119 {
 120         outb(reg, WDT_EFER);
 121         return inb(WDT_EFDR);
 122 }
 123
 124 static int superio_enter(void)
 125 {
 126         if (!request_muxed_region(wdt_io, 2, WATCHDOG_NAME))
 127                 return -EBUSY;
 128
 129         outb_p(0x87, WDT_EFER); /* Enter extended function mode */
 130         outb_p(0x87, WDT_EFER); /* Again according to manual */
 131
 132         return 0;
 133 }
 134
 135 static void superio_select(int ld)
 136 {
 137         superio_outb(0x07, ld);
 138 }
 139
 140 static void superio_exit(void)
 141 {
 142         outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
 143         release_region(wdt_io, 2);
 144 }
 145
 146 static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
 147 {
 148         int ret;
 149         unsigned char t;
 150
 151         ret = superio_enter();
 152         if (ret)
 153                 return ret;
 154
 155         superio_select(W83627HF_LD_WDT);
 156
 157         /* set CR30 bit 0 to activate GPIO2 */
 158         t = superio_inb(0x30);
 159         if (!(t & 0x01))
 160                 superio_outb(0x30, t | 0x01);
 161
 162         switch (chip) {
 163         case w83627hf:
 164         case w83627s:
 165                 t = superio_inb(0x2B) & ~0x10;
 166                 superio_outb(0x2B, t); /* set GPIO24 to WDT0 */
 167                 break;
 168         case w83697hf:
 169                 /* Set pin 119 to WDTO# mode (= CR29, WDT0) */
 170                 t = superio_inb(0x29) & ~0x60;
 171                 t |= 0x20;
 172                 superio_outb(0x29, t);
 173                 break;
 174         case w83697ug:
 175                 /* Set pin 118 to WDTO# mode */
 176                 t = superio_inb(0x2b) & ~0x04;
 177                 superio_outb(0x2b, t);
 178                 break;
 179         case w83627thf:
 180                 t = (superio_inb(0x2B) & ~0x08) | 0x04;
 181                 superio_outb(0x2B, t); /* set GPIO3 to WDT0 */
 182                 break;
 183         case w83627dhg:
 184         case w83627dhg_p:
 185                 t = superio_inb(0x2D) & ~0x01; /* PIN77 -> WDT0# */
 186                 superio_outb(0x2D, t); /* set GPIO5 to WDT0 */
 187                 t = superio_inb(cr_wdt_control);
 188                 t |= 0x02;      /* enable the WDTO# output low pulse
 189                                  * to the KBRST# pin */
 190                 superio_outb(cr_wdt_control, t);
 191                 break;
 192         case w83637hf:
 193                 break;
 194         case w83687thf:
 195                 t = superio_inb(0x2C) & ~0x80; /* PIN47 -> WDT0# */
 196                 superio_outb(0x2C, t);
 197                 break;
 198         case w83627ehf:
 199         case w83627uhg:
 200         case w83667hg:
 201         case w83667hg_b:
 202         case nct6775:
 203         case nct6776:
 204         case nct6779:
 205         case nct6791:
 206         case nct6792:
 207         case nct6102:
 208                 /*
 209                  * These chips have a fixed WDTO# output pin (W83627UHG),
 210                  * or support more than one WDTO# output pin.
 211                  * Don't touch its configuration, and hope the BIOS
 212                  * does the right thing.
 213                  */
 214                 t = superio_inb(cr_wdt_control);
 215                 t |= 0x02;      /* enable the WDTO# output low pulse
 216                                  * to the KBRST# pin */
 217                 superio_outb(cr_wdt_control, t);
 218                 break;
 219         default:
 220                 break;
 221         }
 222
 223         t = superio_inb(cr_wdt_timeout);
 224         if (t != 0) {
 225                 if (early_disable) {
 226                         pr_warn("Stopping previously enabled watchdog until userland kicks in\n");
 227                         superio_outb(cr_wdt_timeout, 0);
 228                 } else {
 229                         pr_info("Watchdog already running. Resetting timeout to %d sec\n",
 230                                 wdog->timeout);
 231                         superio_outb(cr_wdt_timeout, wdog->timeout);
 232                 }
 233         }
 234
 235         /* set second mode & disable keyboard turning off watchdog */
 236         t = superio_inb(cr_wdt_control) & ~0x0C;
 237         superio_outb(cr_wdt_control, t);
 238
 239         /* reset trigger, disable keyboard & mouse turning off watchdog */
 240         t = superio_inb(cr_wdt_csr) & ~0xD0;
 241         superio_outb(cr_wdt_csr, t);
 242
 243         superio_exit();
 244
 245         return 0;
 246 }
 247
 248 static int wdt_set_time(unsigned int timeout)
 249 {
 250         int ret;
 251
 252         ret = superio_enter();
 253         if (ret)
 254                 return ret;
 255
 256         superio_select(W83627HF_LD_WDT);
 257         superio_outb(cr_wdt_timeout, timeout);
 258         superio_exit();
 259
 260         return 0;
 261 }
 262
 263 static int wdt_start(struct watchdog_device *wdog)
 264 {
 265         return wdt_set_time(wdog->timeout);
 266 }
 267
 268 static int wdt_stop(struct watchdog_device *wdog)
 269 {
 270         return wdt_set_time(0);
 271 }
 272
 273 static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
 274 {
 275         wdog->timeout = timeout;
 276
 277         return 0;
 278 }
 279
 280 static unsigned int wdt_get_time(struct watchdog_device *wdog)
 281 {
 282         unsigned int timeleft;
 283         int ret;
 284
 285         ret = superio_enter();
 286         if (ret)
 287                 return 0;
 288
 289         superio_select(W83627HF_LD_WDT);
 290         timeleft = superio_inb(cr_wdt_timeout);
 291         superio_exit();
 292
 293         return timeleft;
 294 }
 295
 296 /*
 297  *      Kernel Interfaces
 298  */
 299
 300 static const struct watchdog_info wdt_info = {
 301         .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
 302         .identity = "W83627HF Watchdog",
 303 };
 304
 305 static const struct watchdog_ops wdt_ops = {
 306         .owner = THIS_MODULE,
 307         .start = wdt_start,
 308         .stop = wdt_stop,
 309         .set_timeout = wdt_set_timeout,
 310         .get_timeleft = wdt_get_time,
 311 };
 312
 313 static struct watchdog_device wdt_dev = {
 314         .info = &wdt_info,
 315         .ops = &wdt_ops,
 316         .timeout = WATCHDOG_TIMEOUT,
 317         .min_timeout = 1,
 318         .max_timeout = 255,
 319 };
 320
 321 /*
 322  *      The WDT needs to learn about soft shutdowns in order to
 323  *      turn the timebomb registers off.
 324  */
 325
 326 static int wdt_find(int addr)
 327 {
 328         u8 val;
 329         int ret;
 330
 331         cr_wdt_timeout = W83627HF_WDT_TIMEOUT;
 332         cr_wdt_control = W83627HF_WDT_CONTROL;
 333         cr_wdt_csr = W836X7HF_WDT_CSR;
 334
 335         ret = superio_enter();
 336         if (ret)
 337                 return ret;
 338         superio_select(W83627HF_LD_WDT);
 339         val = superio_inb(0x20);
 340         switch (val) {
 341         case W83627HF_ID:
 342                 ret = w83627hf;
 343                 break;
 344         case W83627S_ID:
 345                 ret = w83627s;
 346                 break;
 347         case W83697HF_ID:
 348                 ret = w83697hf;
 349                 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
 350                 cr_wdt_control = W83697HF_WDT_CONTROL;
 351                 break;
 352         case W83697UG_ID:
 353                 ret = w83697ug;
 354                 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
 355                 cr_wdt_control = W83697HF_WDT_CONTROL;
 356                 break;
 357         case W83637HF_ID:
 358                 ret = w83637hf;
 359                 break;
 360         case W83627THF_ID:
 361                 ret = w83627thf;
 362                 break;
 363         case W83687THF_ID:
 364                 ret = w83687thf;
 365                 break;
 366         case W83627EHF_ID:
 367                 ret = w83627ehf;
 368                 break;
 369         case W83627DHG_ID:
 370                 ret = w83627dhg;
 371                 break;
 372         case W83627DHG_P_ID:
 373                 ret = w83627dhg_p;
 374                 break;
 375         case W83627UHG_ID:
 376                 ret = w83627uhg;
 377                 break;
 378         case W83667HG_ID:
 379                 ret = w83667hg;
 380                 break;
 381         case W83667HG_B_ID:
 382                 ret = w83667hg_b;
 383                 break;
 384         case NCT6775_ID:
 385                 ret = nct6775;
 386                 break;
 387         case NCT6776_ID:
 388                 ret = nct6776;
 389                 break;
 390         case NCT6779_ID:
 391                 ret = nct6779;
 392                 break;
 393         case NCT6791_ID:
 394                 ret = nct6791;
 395                 break;
 396         case NCT6792_ID:
 397                 ret = nct6792;
 398                 break;
 399         case NCT6102_ID:
 400                 ret = nct6102;
 401                 cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
 402                 cr_wdt_control = NCT6102D_WDT_CONTROL;
 403                 cr_wdt_csr = NCT6102D_WDT_CSR;
 404                 break;
 405         case 0xff:
 406                 ret = -ENODEV;
 407                 break;
 408         default:
 409                 ret = -ENODEV;
 410                 pr_err("Unsupported chip ID: 0x%02x\n", val);
 411                 break;
 412         }
 413         superio_exit();
 414         return ret;
 415 }
 416
 417 static int __init wdt_init(void)
 418 {
 419         int ret;
 420         int chip;
 421         const char * const chip_name[] = {
 422                 "W83627HF",
 423                 "W83627S",
 424                 "W83697HF",
 425                 "W83697UG",
 426                 "W83637HF",
 427                 "W83627THF",
 428                 "W83687THF",
 429                 "W83627EHF",
 430                 "W83627DHG",
 431                 "W83627UHG",
 432                 "W83667HG",
 433                 "W83667DHG-P",
 434                 "W83667HG-B",
 435                 "NCT6775",
 436                 "NCT6776",
 437                 "NCT6779",
 438                 "NCT6791",
 439                 "NCT6792",
 440                 "NCT6102",
 441         };
 442
 443         wdt_io = 0x2e;
 444         chip = wdt_find(0x2e);
 445         if (chip < 0) {
 446                 wdt_io = 0x4e;
 447                 chip = wdt_find(0x4e);
 448                 if (chip < 0)
 449                         return chip;
 450         }
 451
 452         pr_info("WDT driver for %s Super I/O chip initialising\n",
 453                 chip_name[chip]);
 454
 455         watchdog_init_timeout(&wdt_dev, timeout, NULL);
 456         watchdog_set_nowayout(&wdt_dev, nowayout);
 457         watchdog_stop_on_reboot(&wdt_dev);
 458
 459         ret = w83627hf_init(&wdt_dev, chip);
 460         if (ret) {
 461                 pr_err("failed to initialize watchdog (err=%d)\n", ret);
 462                 return ret;
 463         }
 464
 465         ret = watchdog_register_device(&wdt_dev);
 466         if (ret)
 467                 return ret;
 468
 469         pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
 470                 wdt_dev.timeout, nowayout);
 471
 472         return ret;
 473 }
 474
 475 static void __exit wdt_exit(void)
 476 {
 477         watchdog_unregister_device(&wdt_dev);
 478 }
 479
 480 module_init(wdt_init);
 481 module_exit(wdt_exit);
 482
 483 MODULE_LICENSE("GPL");
 484 MODULE_AUTHOR("Pádraig  Brady <P@draigBrady.com>");
 485 MODULE_DESCRIPTION("w83627hf/thf WDT driver");