linux/drivers/watchdog/iTCO_wdt.c
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   1/*
   2 *      intel TCO Watchdog Driver
   3 *
   4 *      (c) Copyright 2006-2011 Wim Van Sebroeck <wim@iguana.be>.
   5 *
   6 *      This program is free software; you can redistribute it and/or
   7 *      modify it under the terms of the GNU General Public License
   8 *      as published by the Free Software Foundation; either version
   9 *      2 of the License, or (at your option) any later version.
  10 *
  11 *      Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
  12 *      provide warranty for any of this software. This material is
  13 *      provided "AS-IS" and at no charge.
  14 *
  15 *      The TCO watchdog is implemented in the following I/O controller hubs:
  16 *      (See the intel documentation on http://developer.intel.com.)
  17 *      document number 290655-003, 290677-014: 82801AA (ICH), 82801AB (ICHO)
  18 *      document number 290687-002, 298242-027: 82801BA (ICH2)
  19 *      document number 290733-003, 290739-013: 82801CA (ICH3-S)
  20 *      document number 290716-001, 290718-007: 82801CAM (ICH3-M)
  21 *      document number 290744-001, 290745-025: 82801DB (ICH4)
  22 *      document number 252337-001, 252663-008: 82801DBM (ICH4-M)
  23 *      document number 273599-001, 273645-002: 82801E (C-ICH)
  24 *      document number 252516-001, 252517-028: 82801EB (ICH5), 82801ER (ICH5R)
  25 *      document number 300641-004, 300884-013: 6300ESB
  26 *      document number 301473-002, 301474-026: 82801F (ICH6)
  27 *      document number 313082-001, 313075-006: 631xESB, 632xESB
  28 *      document number 307013-003, 307014-024: 82801G (ICH7)
  29 *      document number 322896-001, 322897-001: NM10
  30 *      document number 313056-003, 313057-017: 82801H (ICH8)
  31 *      document number 316972-004, 316973-012: 82801I (ICH9)
  32 *      document number 319973-002, 319974-002: 82801J (ICH10)
  33 *      document number 322169-001, 322170-003: 5 Series, 3400 Series (PCH)
  34 *      document number 320066-003, 320257-008: EP80597 (IICH)
  35 *      document number 324645-001, 324646-001: Cougar Point (CPT)
  36 *      document number TBD                   : Patsburg (PBG)
  37 *      document number TBD                   : DH89xxCC
  38 *      document number TBD                   : Panther Point
  39 *      document number TBD                   : Lynx Point
  40 *      document number TBD                   : Lynx Point-LP
  41 */
  42
  43/*
  44 *      Includes, defines, variables, module parameters, ...
  45 */
  46
  47#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  48
  49/* Module and version information */
  50#define DRV_NAME        "iTCO_wdt"
  51#define DRV_VERSION     "1.11"
  52
  53/* Includes */
  54#include <linux/acpi.h>                 /* For ACPI support */
  55#include <linux/module.h>               /* For module specific items */
  56#include <linux/moduleparam.h>          /* For new moduleparam's */
  57#include <linux/types.h>                /* For standard types (like size_t) */
  58#include <linux/errno.h>                /* For the -ENODEV/... values */
  59#include <linux/kernel.h>               /* For printk/panic/... */
  60#include <linux/watchdog.h>             /* For the watchdog specific items */
  61#include <linux/init.h>                 /* For __init/__exit/... */
  62#include <linux/fs.h>                   /* For file operations */
  63#include <linux/platform_device.h>      /* For platform_driver framework */
  64#include <linux/pci.h>                  /* For pci functions */
  65#include <linux/ioport.h>               /* For io-port access */
  66#include <linux/spinlock.h>             /* For spin_lock/spin_unlock/... */
  67#include <linux/uaccess.h>              /* For copy_to_user/put_user/... */
  68#include <linux/io.h>                   /* For inb/outb/... */
  69#include <linux/mfd/core.h>
  70#include <linux/mfd/lpc_ich.h>
  71
  72#include "iTCO_vendor.h"
  73
  74/* Address definitions for the TCO */
  75/* TCO base address */
  76#define TCOBASE         (iTCO_wdt_private.tco_res->start)
  77/* SMI Control and Enable Register */
  78#define SMI_EN          (iTCO_wdt_private.smi_res->start)
  79
  80#define TCO_RLD         (TCOBASE + 0x00) /* TCO Timer Reload and Curr. Value */
  81#define TCOv1_TMR       (TCOBASE + 0x01) /* TCOv1 Timer Initial Value   */
  82#define TCO_DAT_IN      (TCOBASE + 0x02) /* TCO Data In Register        */
  83#define TCO_DAT_OUT     (TCOBASE + 0x03) /* TCO Data Out Register       */
  84#define TCO1_STS        (TCOBASE + 0x04) /* TCO1 Status Register        */
  85#define TCO2_STS        (TCOBASE + 0x06) /* TCO2 Status Register        */
  86#define TCO1_CNT        (TCOBASE + 0x08) /* TCO1 Control Register       */
  87#define TCO2_CNT        (TCOBASE + 0x0a) /* TCO2 Control Register       */
  88#define TCOv2_TMR       (TCOBASE + 0x12) /* TCOv2 Timer Initial Value   */
  89
  90/* internal variables */
  91static struct {         /* this is private data for the iTCO_wdt device */
  92        /* TCO version/generation */
  93        unsigned int iTCO_version;
  94        struct resource *tco_res;
  95        struct resource *smi_res;
  96        /*
  97         * NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2),
  98         * or memory-mapped PMC register bit 4 (TCO version 3).
  99         */
 100        struct resource *gcs_pmc_res;
 101        unsigned long __iomem *gcs_pmc;
 102        /* the lock for io operations */
 103        spinlock_t io_lock;
 104        struct platform_device *dev;
 105        /* the PCI-device */
 106        struct pci_dev *pdev;
 107        /* whether or not the watchdog has been suspended */
 108        bool suspended;
 109} iTCO_wdt_private;
 110
 111/* module parameters */
 112#define WATCHDOG_TIMEOUT 30     /* 30 sec default heartbeat */
 113static int heartbeat = WATCHDOG_TIMEOUT;  /* in seconds */
 114module_param(heartbeat, int, 0);
 115MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. "
 116        "5..76 (TCO v1) or 3..614 (TCO v2), default="
 117                                __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
 118
 119static bool nowayout = WATCHDOG_NOWAYOUT;
 120module_param(nowayout, bool, 0);
 121MODULE_PARM_DESC(nowayout,
 122        "Watchdog cannot be stopped once started (default="
 123                                __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 124
 125static int turn_SMI_watchdog_clear_off = 1;
 126module_param(turn_SMI_watchdog_clear_off, int, 0);
 127MODULE_PARM_DESC(turn_SMI_watchdog_clear_off,
 128        "Turn off SMI clearing watchdog (depends on TCO-version)(default=1)");
 129
 130/*
 131 * Some TCO specific functions
 132 */
 133
 134/*
 135 * The iTCO v1 and v2's internal timer is stored as ticks which decrement
 136 * every 0.6 seconds.  v3's internal timer is stored as seconds (some
 137 * datasheets incorrectly state 0.6 seconds).
 138 */
 139static inline unsigned int seconds_to_ticks(int secs)
 140{
 141        return iTCO_wdt_private.iTCO_version == 3 ? secs : (secs * 10) / 6;
 142}
 143
 144static inline unsigned int ticks_to_seconds(int ticks)
 145{
 146        return iTCO_wdt_private.iTCO_version == 3 ? ticks : (ticks * 6) / 10;
 147}
 148
 149static void iTCO_wdt_set_NO_REBOOT_bit(void)
 150{
 151        u32 val32;
 152
 153        /* Set the NO_REBOOT bit: this disables reboots */
 154        if (iTCO_wdt_private.iTCO_version == 3) {
 155                val32 = readl(iTCO_wdt_private.gcs_pmc);
 156                val32 |= 0x00000010;
 157                writel(val32, iTCO_wdt_private.gcs_pmc);
 158        } else if (iTCO_wdt_private.iTCO_version == 2) {
 159                val32 = readl(iTCO_wdt_private.gcs_pmc);
 160                val32 |= 0x00000020;
 161                writel(val32, iTCO_wdt_private.gcs_pmc);
 162        } else if (iTCO_wdt_private.iTCO_version == 1) {
 163                pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
 164                val32 |= 0x00000002;
 165                pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
 166        }
 167}
 168
 169static int iTCO_wdt_unset_NO_REBOOT_bit(void)
 170{
 171        int ret = 0;
 172        u32 val32;
 173
 174        /* Unset the NO_REBOOT bit: this enables reboots */
 175        if (iTCO_wdt_private.iTCO_version == 3) {
 176                val32 = readl(iTCO_wdt_private.gcs_pmc);
 177                val32 &= 0xffffffef;
 178                writel(val32, iTCO_wdt_private.gcs_pmc);
 179
 180                val32 = readl(iTCO_wdt_private.gcs_pmc);
 181                if (val32 & 0x00000010)
 182                        ret = -EIO;
 183        } else if (iTCO_wdt_private.iTCO_version == 2) {
 184                val32 = readl(iTCO_wdt_private.gcs_pmc);
 185                val32 &= 0xffffffdf;
 186                writel(val32, iTCO_wdt_private.gcs_pmc);
 187
 188                val32 = readl(iTCO_wdt_private.gcs_pmc);
 189                if (val32 & 0x00000020)
 190                        ret = -EIO;
 191        } else if (iTCO_wdt_private.iTCO_version == 1) {
 192                pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
 193                val32 &= 0xfffffffd;
 194                pci_write_config_dword(iTCO_wdt_private.pdev, 0xd4, val32);
 195
 196                pci_read_config_dword(iTCO_wdt_private.pdev, 0xd4, &val32);
 197                if (val32 & 0x00000002)
 198                        ret = -EIO;
 199        }
 200
 201        return ret; /* returns: 0 = OK, -EIO = Error */
 202}
 203
 204static int iTCO_wdt_start(struct watchdog_device *wd_dev)
 205{
 206        unsigned int val;
 207
 208        spin_lock(&iTCO_wdt_private.io_lock);
 209
 210        iTCO_vendor_pre_start(iTCO_wdt_private.smi_res, wd_dev->timeout);
 211
 212        /* disable chipset's NO_REBOOT bit */
 213        if (iTCO_wdt_unset_NO_REBOOT_bit()) {
 214                spin_unlock(&iTCO_wdt_private.io_lock);
 215                pr_err("failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n");
 216                return -EIO;
 217        }
 218
 219        /* Force the timer to its reload value by writing to the TCO_RLD
 220           register */
 221        if (iTCO_wdt_private.iTCO_version >= 2)
 222                outw(0x01, TCO_RLD);
 223        else if (iTCO_wdt_private.iTCO_version == 1)
 224                outb(0x01, TCO_RLD);
 225
 226        /* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */
 227        val = inw(TCO1_CNT);
 228        val &= 0xf7ff;
 229        outw(val, TCO1_CNT);
 230        val = inw(TCO1_CNT);
 231        spin_unlock(&iTCO_wdt_private.io_lock);
 232
 233        if (val & 0x0800)
 234                return -1;
 235        return 0;
 236}
 237
 238static int iTCO_wdt_stop(struct watchdog_device *wd_dev)
 239{
 240        unsigned int val;
 241
 242        spin_lock(&iTCO_wdt_private.io_lock);
 243
 244        iTCO_vendor_pre_stop(iTCO_wdt_private.smi_res);
 245
 246        /* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */
 247        val = inw(TCO1_CNT);
 248        val |= 0x0800;
 249        outw(val, TCO1_CNT);
 250        val = inw(TCO1_CNT);
 251
 252        /* Set the NO_REBOOT bit to prevent later reboots, just for sure */
 253        iTCO_wdt_set_NO_REBOOT_bit();
 254
 255        spin_unlock(&iTCO_wdt_private.io_lock);
 256
 257        if ((val & 0x0800) == 0)
 258                return -1;
 259        return 0;
 260}
 261
 262static int iTCO_wdt_ping(struct watchdog_device *wd_dev)
 263{
 264        spin_lock(&iTCO_wdt_private.io_lock);
 265
 266        iTCO_vendor_pre_keepalive(iTCO_wdt_private.smi_res, wd_dev->timeout);
 267
 268        /* Reload the timer by writing to the TCO Timer Counter register */
 269        if (iTCO_wdt_private.iTCO_version >= 2) {
 270                outw(0x01, TCO_RLD);
 271        } else if (iTCO_wdt_private.iTCO_version == 1) {
 272                /* Reset the timeout status bit so that the timer
 273                 * needs to count down twice again before rebooting */
 274                outw(0x0008, TCO1_STS); /* write 1 to clear bit */
 275
 276                outb(0x01, TCO_RLD);
 277        }
 278
 279        spin_unlock(&iTCO_wdt_private.io_lock);
 280        return 0;
 281}
 282
 283static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
 284{
 285        unsigned int val16;
 286        unsigned char val8;
 287        unsigned int tmrval;
 288
 289        tmrval = seconds_to_ticks(t);
 290
 291        /* For TCO v1 the timer counts down twice before rebooting */
 292        if (iTCO_wdt_private.iTCO_version == 1)
 293                tmrval /= 2;
 294
 295        /* from the specs: */
 296        /* "Values of 0h-3h are ignored and should not be attempted" */
 297        if (tmrval < 0x04)
 298                return -EINVAL;
 299        if (((iTCO_wdt_private.iTCO_version >= 2) && (tmrval > 0x3ff)) ||
 300            ((iTCO_wdt_private.iTCO_version == 1) && (tmrval > 0x03f)))
 301                return -EINVAL;
 302
 303        iTCO_vendor_pre_set_heartbeat(tmrval);
 304
 305        /* Write new heartbeat to watchdog */
 306        if (iTCO_wdt_private.iTCO_version >= 2) {
 307                spin_lock(&iTCO_wdt_private.io_lock);
 308                val16 = inw(TCOv2_TMR);
 309                val16 &= 0xfc00;
 310                val16 |= tmrval;
 311                outw(val16, TCOv2_TMR);
 312                val16 = inw(TCOv2_TMR);
 313                spin_unlock(&iTCO_wdt_private.io_lock);
 314
 315                if ((val16 & 0x3ff) != tmrval)
 316                        return -EINVAL;
 317        } else if (iTCO_wdt_private.iTCO_version == 1) {
 318                spin_lock(&iTCO_wdt_private.io_lock);
 319                val8 = inb(TCOv1_TMR);
 320                val8 &= 0xc0;
 321                val8 |= (tmrval & 0xff);
 322                outb(val8, TCOv1_TMR);
 323                val8 = inb(TCOv1_TMR);
 324                spin_unlock(&iTCO_wdt_private.io_lock);
 325
 326                if ((val8 & 0x3f) != tmrval)
 327                        return -EINVAL;
 328        }
 329
 330        wd_dev->timeout = t;
 331        return 0;
 332}
 333
 334static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
 335{
 336        unsigned int val16;
 337        unsigned char val8;
 338        unsigned int time_left = 0;
 339
 340        /* read the TCO Timer */
 341        if (iTCO_wdt_private.iTCO_version >= 2) {
 342                spin_lock(&iTCO_wdt_private.io_lock);
 343                val16 = inw(TCO_RLD);
 344                val16 &= 0x3ff;
 345                spin_unlock(&iTCO_wdt_private.io_lock);
 346
 347                time_left = ticks_to_seconds(val16);
 348        } else if (iTCO_wdt_private.iTCO_version == 1) {
 349                spin_lock(&iTCO_wdt_private.io_lock);
 350                val8 = inb(TCO_RLD);
 351                val8 &= 0x3f;
 352                if (!(inw(TCO1_STS) & 0x0008))
 353                        val8 += (inb(TCOv1_TMR) & 0x3f);
 354                spin_unlock(&iTCO_wdt_private.io_lock);
 355
 356                time_left = ticks_to_seconds(val8);
 357        }
 358        return time_left;
 359}
 360
 361/*
 362 *      Kernel Interfaces
 363 */
 364
 365static const struct watchdog_info ident = {
 366        .options =              WDIOF_SETTIMEOUT |
 367                                WDIOF_KEEPALIVEPING |
 368                                WDIOF_MAGICCLOSE,
 369        .firmware_version =     0,
 370        .identity =             DRV_NAME,
 371};
 372
 373static const struct watchdog_ops iTCO_wdt_ops = {
 374        .owner =                THIS_MODULE,
 375        .start =                iTCO_wdt_start,
 376        .stop =                 iTCO_wdt_stop,
 377        .ping =                 iTCO_wdt_ping,
 378        .set_timeout =          iTCO_wdt_set_timeout,
 379        .get_timeleft =         iTCO_wdt_get_timeleft,
 380};
 381
 382static struct watchdog_device iTCO_wdt_watchdog_dev = {
 383        .info =         &ident,
 384        .ops =          &iTCO_wdt_ops,
 385};
 386
 387/*
 388 *      Init & exit routines
 389 */
 390
 391static void iTCO_wdt_cleanup(void)
 392{
 393        /* Stop the timer before we leave */
 394        if (!nowayout)
 395                iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
 396
 397        /* Deregister */
 398        watchdog_unregister_device(&iTCO_wdt_watchdog_dev);
 399
 400        /* release resources */
 401        release_region(iTCO_wdt_private.tco_res->start,
 402                        resource_size(iTCO_wdt_private.tco_res));
 403        release_region(iTCO_wdt_private.smi_res->start,
 404                        resource_size(iTCO_wdt_private.smi_res));
 405        if (iTCO_wdt_private.iTCO_version >= 2) {
 406                iounmap(iTCO_wdt_private.gcs_pmc);
 407                release_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
 408                                resource_size(iTCO_wdt_private.gcs_pmc_res));
 409        }
 410
 411        iTCO_wdt_private.tco_res = NULL;
 412        iTCO_wdt_private.smi_res = NULL;
 413        iTCO_wdt_private.gcs_pmc_res = NULL;
 414        iTCO_wdt_private.gcs_pmc = NULL;
 415}
 416
 417static int iTCO_wdt_probe(struct platform_device *dev)
 418{
 419        int ret = -ENODEV;
 420        unsigned long val32;
 421        struct lpc_ich_info *ich_info = dev_get_platdata(&dev->dev);
 422
 423        if (!ich_info)
 424                goto out;
 425
 426        spin_lock_init(&iTCO_wdt_private.io_lock);
 427
 428        iTCO_wdt_private.tco_res =
 429                platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_TCO);
 430        if (!iTCO_wdt_private.tco_res)
 431                goto out;
 432
 433        iTCO_wdt_private.smi_res =
 434                platform_get_resource(dev, IORESOURCE_IO, ICH_RES_IO_SMI);
 435        if (!iTCO_wdt_private.smi_res)
 436                goto out;
 437
 438        iTCO_wdt_private.iTCO_version = ich_info->iTCO_version;
 439        iTCO_wdt_private.dev = dev;
 440        iTCO_wdt_private.pdev = to_pci_dev(dev->dev.parent);
 441
 442        /*
 443         * Get the Memory-Mapped GCS or PMC register, we need it for the
 444         * NO_REBOOT flag (TCO v2 and v3).
 445         */
 446        if (iTCO_wdt_private.iTCO_version >= 2) {
 447                iTCO_wdt_private.gcs_pmc_res = platform_get_resource(dev,
 448                                                        IORESOURCE_MEM,
 449                                                        ICH_RES_MEM_GCS_PMC);
 450
 451                if (!iTCO_wdt_private.gcs_pmc_res)
 452                        goto out;
 453
 454                if (!request_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
 455                        resource_size(iTCO_wdt_private.gcs_pmc_res), dev->name)) {
 456                        ret = -EBUSY;
 457                        goto out;
 458                }
 459                iTCO_wdt_private.gcs_pmc = ioremap(iTCO_wdt_private.gcs_pmc_res->start,
 460                        resource_size(iTCO_wdt_private.gcs_pmc_res));
 461                if (!iTCO_wdt_private.gcs_pmc) {
 462                        ret = -EIO;
 463                        goto unreg_gcs_pmc;
 464                }
 465        }
 466
 467        /* Check chipset's NO_REBOOT bit */
 468        if (iTCO_wdt_unset_NO_REBOOT_bit() && iTCO_vendor_check_noreboot_on()) {
 469                pr_info("unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n");
 470                ret = -ENODEV;  /* Cannot reset NO_REBOOT bit */
 471                goto unmap_gcs_pmc;
 472        }
 473
 474        /* Set the NO_REBOOT bit to prevent later reboots, just for sure */
 475        iTCO_wdt_set_NO_REBOOT_bit();
 476
 477        /* The TCO logic uses the TCO_EN bit in the SMI_EN register */
 478        if (!request_region(iTCO_wdt_private.smi_res->start,
 479                        resource_size(iTCO_wdt_private.smi_res), dev->name)) {
 480                pr_err("I/O address 0x%04llx already in use, device disabled\n",
 481                       (u64)SMI_EN);
 482                ret = -EBUSY;
 483                goto unmap_gcs_pmc;
 484        }
 485        if (turn_SMI_watchdog_clear_off >= iTCO_wdt_private.iTCO_version) {
 486                /*
 487                 * Bit 13: TCO_EN -> 0
 488                 * Disables TCO logic generating an SMI#
 489                 */
 490                val32 = inl(SMI_EN);
 491                val32 &= 0xffffdfff;    /* Turn off SMI clearing watchdog */
 492                outl(val32, SMI_EN);
 493        }
 494
 495        if (!request_region(iTCO_wdt_private.tco_res->start,
 496                        resource_size(iTCO_wdt_private.tco_res), dev->name)) {
 497                pr_err("I/O address 0x%04llx already in use, device disabled\n",
 498                       (u64)TCOBASE);
 499                ret = -EBUSY;
 500                goto unreg_smi;
 501        }
 502
 503        pr_info("Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n",
 504                ich_info->name, ich_info->iTCO_version, (u64)TCOBASE);
 505
 506        /* Clear out the (probably old) status */
 507        if (iTCO_wdt_private.iTCO_version == 3) {
 508                outl(0x20008, TCO1_STS);
 509        } else {
 510                outw(0x0008, TCO1_STS); /* Clear the Time Out Status bit */
 511                outw(0x0002, TCO2_STS); /* Clear SECOND_TO_STS bit */
 512                outw(0x0004, TCO2_STS); /* Clear BOOT_STS bit */
 513        }
 514
 515        iTCO_wdt_watchdog_dev.bootstatus = 0;
 516        iTCO_wdt_watchdog_dev.timeout = WATCHDOG_TIMEOUT;
 517        watchdog_set_nowayout(&iTCO_wdt_watchdog_dev, nowayout);
 518        iTCO_wdt_watchdog_dev.parent = &dev->dev;
 519
 520        /* Make sure the watchdog is not running */
 521        iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
 522
 523        /* Check that the heartbeat value is within it's range;
 524           if not reset to the default */
 525        if (iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, heartbeat)) {
 526                iTCO_wdt_set_timeout(&iTCO_wdt_watchdog_dev, WATCHDOG_TIMEOUT);
 527                pr_info("timeout value out of range, using %d\n",
 528                        WATCHDOG_TIMEOUT);
 529        }
 530
 531        ret = watchdog_register_device(&iTCO_wdt_watchdog_dev);
 532        if (ret != 0) {
 533                pr_err("cannot register watchdog device (err=%d)\n", ret);
 534                goto unreg_tco;
 535        }
 536
 537        pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
 538                heartbeat, nowayout);
 539
 540        return 0;
 541
 542unreg_tco:
 543        release_region(iTCO_wdt_private.tco_res->start,
 544                        resource_size(iTCO_wdt_private.tco_res));
 545unreg_smi:
 546        release_region(iTCO_wdt_private.smi_res->start,
 547                        resource_size(iTCO_wdt_private.smi_res));
 548unmap_gcs_pmc:
 549        if (iTCO_wdt_private.iTCO_version >= 2)
 550                iounmap(iTCO_wdt_private.gcs_pmc);
 551unreg_gcs_pmc:
 552        if (iTCO_wdt_private.iTCO_version >= 2)
 553                release_mem_region(iTCO_wdt_private.gcs_pmc_res->start,
 554                                resource_size(iTCO_wdt_private.gcs_pmc_res));
 555out:
 556        iTCO_wdt_private.tco_res = NULL;
 557        iTCO_wdt_private.smi_res = NULL;
 558        iTCO_wdt_private.gcs_pmc_res = NULL;
 559        iTCO_wdt_private.gcs_pmc = NULL;
 560
 561        return ret;
 562}
 563
 564static int iTCO_wdt_remove(struct platform_device *dev)
 565{
 566        if (iTCO_wdt_private.tco_res || iTCO_wdt_private.smi_res)
 567                iTCO_wdt_cleanup();
 568
 569        return 0;
 570}
 571
 572static void iTCO_wdt_shutdown(struct platform_device *dev)
 573{
 574        iTCO_wdt_stop(NULL);
 575}
 576
 577#ifdef CONFIG_PM_SLEEP
 578/*
 579 * Suspend-to-idle requires this, because it stops the ticks and timekeeping, so
 580 * the watchdog cannot be pinged while in that state.  In ACPI sleep states the
 581 * watchdog is stopped by the platform firmware.
 582 */
 583
 584#ifdef CONFIG_ACPI
 585static inline bool need_suspend(void)
 586{
 587        return acpi_target_system_state() == ACPI_STATE_S0;
 588}
 589#else
 590static inline bool need_suspend(void) { return true; }
 591#endif
 592
 593static int iTCO_wdt_suspend_noirq(struct device *dev)
 594{
 595        int ret = 0;
 596
 597        iTCO_wdt_private.suspended = false;
 598        if (watchdog_active(&iTCO_wdt_watchdog_dev) && need_suspend()) {
 599                ret = iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
 600                if (!ret)
 601                        iTCO_wdt_private.suspended = true;
 602        }
 603        return ret;
 604}
 605
 606static int iTCO_wdt_resume_noirq(struct device *dev)
 607{
 608        if (iTCO_wdt_private.suspended)
 609                iTCO_wdt_start(&iTCO_wdt_watchdog_dev);
 610
 611        return 0;
 612}
 613
 614static struct dev_pm_ops iTCO_wdt_pm = {
 615        .suspend_noirq = iTCO_wdt_suspend_noirq,
 616        .resume_noirq = iTCO_wdt_resume_noirq,
 617};
 618
 619#define ITCO_WDT_PM_OPS (&iTCO_wdt_pm)
 620#else
 621#define ITCO_WDT_PM_OPS NULL
 622#endif /* CONFIG_PM_SLEEP */
 623
 624static struct platform_driver iTCO_wdt_driver = {
 625        .probe          = iTCO_wdt_probe,
 626        .remove         = iTCO_wdt_remove,
 627        .shutdown       = iTCO_wdt_shutdown,
 628        .driver         = {
 629                .name   = DRV_NAME,
 630                .pm     = ITCO_WDT_PM_OPS,
 631        },
 632};
 633
 634static int __init iTCO_wdt_init_module(void)
 635{
 636        int err;
 637
 638        pr_info("Intel TCO WatchDog Timer Driver v%s\n", DRV_VERSION);
 639
 640        err = platform_driver_register(&iTCO_wdt_driver);
 641        if (err)
 642                return err;
 643
 644        return 0;
 645}
 646
 647static void __exit iTCO_wdt_cleanup_module(void)
 648{
 649        platform_driver_unregister(&iTCO_wdt_driver);
 650        pr_info("Watchdog Module Unloaded\n");
 651}
 652
 653module_init(iTCO_wdt_init_module);
 654module_exit(iTCO_wdt_cleanup_module);
 655
 656MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
 657MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver");
 658MODULE_VERSION(DRV_VERSION);
 659MODULE_LICENSE("GPL");
 660MODULE_ALIAS("platform:" DRV_NAME);
 661