1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * intel TCO Watchdog Driver 4 * 5 * (c) Copyright 2006-2011 Wim Van Sebroeck <wim@iguana.be>. 6 * 7 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor 8 * provide warranty for any of this software. This material is 9 * provided "AS-IS" and at no charge. 10 * 11 * The TCO watchdog is implemented in the following I/O controller hubs: 12 * (See the intel documentation on http://developer.intel.com.) 13 * document number 290655-003, 290677-014: 82801AA (ICH), 82801AB (ICHO) 14 * document number 290687-002, 298242-027: 82801BA (ICH2) 15 * document number 290733-003, 290739-013: 82801CA (ICH3-S) 16 * document number 290716-001, 290718-007: 82801CAM (ICH3-M) 17 * document number 290744-001, 290745-025: 82801DB (ICH4) 18 * document number 252337-001, 252663-008: 82801DBM (ICH4-M) 19 * document number 273599-001, 273645-002: 82801E (C-ICH) 20 * document number 252516-001, 252517-028: 82801EB (ICH5), 82801ER (ICH5R) 21 * document number 300641-004, 300884-013: 6300ESB 22 * document number 301473-002, 301474-026: 82801F (ICH6) 23 * document number 313082-001, 313075-006: 631xESB, 632xESB 24 * document number 307013-003, 307014-024: 82801G (ICH7) 25 * document number 322896-001, 322897-001: NM10 26 * document number 313056-003, 313057-017: 82801H (ICH8) 27 * document number 316972-004, 316973-012: 82801I (ICH9) 28 * document number 319973-002, 319974-002: 82801J (ICH10) 29 * document number 322169-001, 322170-003: 5 Series, 3400 Series (PCH) 30 * document number 320066-003, 320257-008: EP80597 (IICH) 31 * document number 324645-001, 324646-001: Cougar Point (CPT) 32 * document number TBD : Patsburg (PBG) 33 * document number TBD : DH89xxCC 34 * document number TBD : Panther Point 35 * document number TBD : Lynx Point 36 * document number TBD : Lynx Point-LP 37 */ 38 39 /* 40 * Includes, defines, variables, module parameters, ... 41 */ 42 43 /* Module and version information */ 44 #define DRV_NAME "iTCO_wdt" 45 #define DRV_VERSION "1.11" 46 47 /* Includes */ 48 #include <linux/acpi.h> /* For ACPI support */ 49 #include <linux/bits.h> /* For BIT() */ 50 #include <linux/module.h> /* For module specific items */ 51 #include <linux/moduleparam.h> /* For new moduleparam's */ 52 #include <linux/types.h> /* For standard types (like size_t) */ 53 #include <linux/errno.h> /* For the -ENODEV/... values */ 54 #include <linux/kernel.h> /* For printk/panic/... */ 55 #include <linux/watchdog.h> /* For the watchdog specific items */ 56 #include <linux/init.h> /* For __init/__exit/... */ 57 #include <linux/fs.h> /* For file operations */ 58 #include <linux/platform_device.h> /* For platform_driver framework */ 59 #include <linux/pci.h> /* For pci functions */ 60 #include <linux/ioport.h> /* For io-port access */ 61 #include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */ 62 #include <linux/uaccess.h> /* For copy_to_user/put_user/... */ 63 #include <linux/io.h> /* For inb/outb/... */ 64 #include <linux/platform_data/itco_wdt.h> 65 #include <linux/mfd/intel_pmc_bxt.h> 66 67 #include "iTCO_vendor.h" 68 69 /* Address definitions for the TCO */ 70 /* TCO base address */ 71 #define TCOBASE(p) ((p)->tco_res->start) 72 /* SMI Control and Enable Register */ 73 #define SMI_EN(p) ((p)->smi_res->start) 74 #define TCO_EN (1 << 13) 75 #define GBL_SMI_EN (1 << 0) 76 77 #define TCO_RLD(p) (TCOBASE(p) + 0x00) /* TCO Timer Reload/Curr. Value */ 78 #define TCOv1_TMR(p) (TCOBASE(p) + 0x01) /* TCOv1 Timer Initial Value*/ 79 #define TCO_DAT_IN(p) (TCOBASE(p) + 0x02) /* TCO Data In Register */ 80 #define TCO_DAT_OUT(p) (TCOBASE(p) + 0x03) /* TCO Data Out Register */ 81 #define TCO1_STS(p) (TCOBASE(p) + 0x04) /* TCO1 Status Register */ 82 #define TCO2_STS(p) (TCOBASE(p) + 0x06) /* TCO2 Status Register */ 83 #define TCO1_CNT(p) (TCOBASE(p) + 0x08) /* TCO1 Control Register */ 84 #define TCO2_CNT(p) (TCOBASE(p) + 0x0a) /* TCO2 Control Register */ 85 #define TCOv2_TMR(p) (TCOBASE(p) + 0x12) /* TCOv2 Timer Initial Value*/ 86 87 /* internal variables */ 88 struct iTCO_wdt_private { 89 struct watchdog_device wddev; 90 91 /* TCO version/generation */ 92 unsigned int iTCO_version; 93 struct resource *tco_res; 94 struct resource *smi_res; 95 /* 96 * NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2), 97 * or memory-mapped PMC register bit 4 (TCO version 3). 98 */ 99 struct resource *gcs_pmc_res; 100 unsigned long __iomem *gcs_pmc; 101 /* the lock for io operations */ 102 spinlock_t io_lock; 103 /* the PCI-device */ 104 struct pci_dev *pci_dev; 105 /* whether or not the watchdog has been suspended */ 106 bool suspended; 107 /* no reboot API private data */ 108 void *no_reboot_priv; 109 /* no reboot update function pointer */ 110 int (*update_no_reboot_bit)(void *p, bool set); 111 }; 112 113 /* module parameters */ 114 #define WATCHDOG_TIMEOUT 30 /* 30 sec default heartbeat */ 115 static int heartbeat = WATCHDOG_TIMEOUT; /* in seconds */ 116 module_param(heartbeat, int, 0); 117 MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. " 118 "5..76 (TCO v1) or 3..614 (TCO v2), default=" 119 __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); 120 121 static bool nowayout = WATCHDOG_NOWAYOUT; 122 module_param(nowayout, bool, 0); 123 MODULE_PARM_DESC(nowayout, 124 "Watchdog cannot be stopped once started (default=" 125 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 126 127 static int turn_SMI_watchdog_clear_off = 1; 128 module_param(turn_SMI_watchdog_clear_off, int, 0); 129 MODULE_PARM_DESC(turn_SMI_watchdog_clear_off, 130 "Turn off SMI clearing watchdog (depends on TCO-version)(default=1)"); 131 132 /* 133 * Some TCO specific functions 134 */ 135 136 /* 137 * The iTCO v1 and v2's internal timer is stored as ticks which decrement 138 * every 0.6 seconds. v3's internal timer is stored as seconds (some 139 * datasheets incorrectly state 0.6 seconds). 140 */ 141 static inline unsigned int seconds_to_ticks(struct iTCO_wdt_private *p, 142 int secs) 143 { 144 return p->iTCO_version == 3 ? secs : (secs * 10) / 6; 145 } 146 147 static inline unsigned int ticks_to_seconds(struct iTCO_wdt_private *p, 148 int ticks) 149 { 150 return p->iTCO_version == 3 ? ticks : (ticks * 6) / 10; 151 } 152 153 static inline u32 no_reboot_bit(struct iTCO_wdt_private *p) 154 { 155 u32 enable_bit; 156 157 switch (p->iTCO_version) { 158 case 5: 159 case 3: 160 enable_bit = 0x00000010; 161 break; 162 case 2: 163 enable_bit = 0x00000020; 164 break; 165 case 4: 166 case 1: 167 default: 168 enable_bit = 0x00000002; 169 break; 170 } 171 172 return enable_bit; 173 } 174 175 static int update_no_reboot_bit_def(void *priv, bool set) 176 { 177 return 0; 178 } 179 180 static int update_no_reboot_bit_pci(void *priv, bool set) 181 { 182 struct iTCO_wdt_private *p = priv; 183 u32 val32 = 0, newval32 = 0; 184 185 pci_read_config_dword(p->pci_dev, 0xd4, &val32); 186 if (set) 187 val32 |= no_reboot_bit(p); 188 else 189 val32 &= ~no_reboot_bit(p); 190 pci_write_config_dword(p->pci_dev, 0xd4, val32); 191 pci_read_config_dword(p->pci_dev, 0xd4, &newval32); 192 193 /* make sure the update is successful */ 194 if (val32 != newval32) 195 return -EIO; 196 197 return 0; 198 } 199 200 static int update_no_reboot_bit_mem(void *priv, bool set) 201 { 202 struct iTCO_wdt_private *p = priv; 203 u32 val32 = 0, newval32 = 0; 204 205 val32 = readl(p->gcs_pmc); 206 if (set) 207 val32 |= no_reboot_bit(p); 208 else 209 val32 &= ~no_reboot_bit(p); 210 writel(val32, p->gcs_pmc); 211 newval32 = readl(p->gcs_pmc); 212 213 /* make sure the update is successful */ 214 if (val32 != newval32) 215 return -EIO; 216 217 return 0; 218 } 219 220 static int update_no_reboot_bit_cnt(void *priv, bool set) 221 { 222 struct iTCO_wdt_private *p = priv; 223 u16 val, newval; 224 225 val = inw(TCO1_CNT(p)); 226 if (set) 227 val |= BIT(0); 228 else 229 val &= ~BIT(0); 230 outw(val, TCO1_CNT(p)); 231 newval = inw(TCO1_CNT(p)); 232 233 /* make sure the update is successful */ 234 return val != newval ? -EIO : 0; 235 } 236 237 static int update_no_reboot_bit_pmc(void *priv, bool set) 238 { 239 struct intel_pmc_dev *pmc = priv; 240 u32 bits = PMC_CFG_NO_REBOOT_EN; 241 u32 value = set ? bits : 0; 242 243 return intel_pmc_gcr_update(pmc, PMC_GCR_PMC_CFG_REG, bits, value); 244 } 245 246 static void iTCO_wdt_no_reboot_bit_setup(struct iTCO_wdt_private *p, 247 struct platform_device *pdev, 248 struct itco_wdt_platform_data *pdata) 249 { 250 if (pdata->no_reboot_use_pmc) { 251 struct intel_pmc_dev *pmc = dev_get_drvdata(pdev->dev.parent); 252 253 p->update_no_reboot_bit = update_no_reboot_bit_pmc; 254 p->no_reboot_priv = pmc; 255 return; 256 } 257 258 if (p->iTCO_version >= 6) 259 p->update_no_reboot_bit = update_no_reboot_bit_cnt; 260 else if (p->iTCO_version >= 2) 261 p->update_no_reboot_bit = update_no_reboot_bit_mem; 262 else if (p->iTCO_version == 1) 263 p->update_no_reboot_bit = update_no_reboot_bit_pci; 264 else 265 p->update_no_reboot_bit = update_no_reboot_bit_def; 266 267 p->no_reboot_priv = p; 268 } 269 270 static int iTCO_wdt_start(struct watchdog_device *wd_dev) 271 { 272 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 273 unsigned int val; 274 275 spin_lock(&p->io_lock); 276 277 iTCO_vendor_pre_start(p->smi_res, wd_dev->timeout); 278 279 /* disable chipset's NO_REBOOT bit */ 280 if (p->update_no_reboot_bit(p->no_reboot_priv, false)) { 281 spin_unlock(&p->io_lock); 282 dev_err(wd_dev->parent, "failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n"); 283 return -EIO; 284 } 285 286 /* Force the timer to its reload value by writing to the TCO_RLD 287 register */ 288 if (p->iTCO_version >= 2) 289 outw(0x01, TCO_RLD(p)); 290 else if (p->iTCO_version == 1) 291 outb(0x01, TCO_RLD(p)); 292 293 /* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */ 294 val = inw(TCO1_CNT(p)); 295 val &= 0xf7ff; 296 outw(val, TCO1_CNT(p)); 297 val = inw(TCO1_CNT(p)); 298 spin_unlock(&p->io_lock); 299 300 if (val & 0x0800) 301 return -1; 302 return 0; 303 } 304 305 static int iTCO_wdt_stop(struct watchdog_device *wd_dev) 306 { 307 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 308 unsigned int val; 309 310 spin_lock(&p->io_lock); 311 312 iTCO_vendor_pre_stop(p->smi_res); 313 314 /* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */ 315 val = inw(TCO1_CNT(p)); 316 val |= 0x0800; 317 outw(val, TCO1_CNT(p)); 318 val = inw(TCO1_CNT(p)); 319 320 /* Set the NO_REBOOT bit to prevent later reboots, just for sure */ 321 p->update_no_reboot_bit(p->no_reboot_priv, true); 322 323 spin_unlock(&p->io_lock); 324 325 if ((val & 0x0800) == 0) 326 return -1; 327 return 0; 328 } 329 330 static int iTCO_wdt_ping(struct watchdog_device *wd_dev) 331 { 332 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 333 334 spin_lock(&p->io_lock); 335 336 /* Reload the timer by writing to the TCO Timer Counter register */ 337 if (p->iTCO_version >= 2) { 338 outw(0x01, TCO_RLD(p)); 339 } else if (p->iTCO_version == 1) { 340 /* Reset the timeout status bit so that the timer 341 * needs to count down twice again before rebooting */ 342 outw(0x0008, TCO1_STS(p)); /* write 1 to clear bit */ 343 344 outb(0x01, TCO_RLD(p)); 345 } 346 347 spin_unlock(&p->io_lock); 348 return 0; 349 } 350 351 static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t) 352 { 353 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 354 unsigned int val16; 355 unsigned char val8; 356 unsigned int tmrval; 357 358 tmrval = seconds_to_ticks(p, t); 359 360 /* 361 * If TCO SMIs are off, the timer counts down twice before rebooting. 362 * Otherwise, the BIOS generally reboots when the SMI triggers. 363 */ 364 if (p->smi_res && 365 (SMI_EN(p) & (TCO_EN | GBL_SMI_EN)) != (TCO_EN | GBL_SMI_EN)) 366 tmrval /= 2; 367 368 /* from the specs: */ 369 /* "Values of 0h-3h are ignored and should not be attempted" */ 370 if (tmrval < 0x04) 371 return -EINVAL; 372 if ((p->iTCO_version >= 2 && tmrval > 0x3ff) || 373 (p->iTCO_version == 1 && tmrval > 0x03f)) 374 return -EINVAL; 375 376 /* Write new heartbeat to watchdog */ 377 if (p->iTCO_version >= 2) { 378 spin_lock(&p->io_lock); 379 val16 = inw(TCOv2_TMR(p)); 380 val16 &= 0xfc00; 381 val16 |= tmrval; 382 outw(val16, TCOv2_TMR(p)); 383 val16 = inw(TCOv2_TMR(p)); 384 spin_unlock(&p->io_lock); 385 386 if ((val16 & 0x3ff) != tmrval) 387 return -EINVAL; 388 } else if (p->iTCO_version == 1) { 389 spin_lock(&p->io_lock); 390 val8 = inb(TCOv1_TMR(p)); 391 val8 &= 0xc0; 392 val8 |= (tmrval & 0xff); 393 outb(val8, TCOv1_TMR(p)); 394 val8 = inb(TCOv1_TMR(p)); 395 spin_unlock(&p->io_lock); 396 397 if ((val8 & 0x3f) != tmrval) 398 return -EINVAL; 399 } 400 401 wd_dev->timeout = t; 402 return 0; 403 } 404 405 static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev) 406 { 407 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 408 unsigned int val16; 409 unsigned char val8; 410 unsigned int time_left = 0; 411 412 /* read the TCO Timer */ 413 if (p->iTCO_version >= 2) { 414 spin_lock(&p->io_lock); 415 val16 = inw(TCO_RLD(p)); 416 val16 &= 0x3ff; 417 spin_unlock(&p->io_lock); 418 419 time_left = ticks_to_seconds(p, val16); 420 } else if (p->iTCO_version == 1) { 421 spin_lock(&p->io_lock); 422 val8 = inb(TCO_RLD(p)); 423 val8 &= 0x3f; 424 if (!(inw(TCO1_STS(p)) & 0x0008)) 425 val8 += (inb(TCOv1_TMR(p)) & 0x3f); 426 spin_unlock(&p->io_lock); 427 428 time_left = ticks_to_seconds(p, val8); 429 } 430 return time_left; 431 } 432 433 /* 434 * Kernel Interfaces 435 */ 436 437 static const struct watchdog_info ident = { 438 .options = WDIOF_SETTIMEOUT | 439 WDIOF_KEEPALIVEPING | 440 WDIOF_MAGICCLOSE, 441 .firmware_version = 0, 442 .identity = DRV_NAME, 443 }; 444 445 static const struct watchdog_ops iTCO_wdt_ops = { 446 .owner = THIS_MODULE, 447 .start = iTCO_wdt_start, 448 .stop = iTCO_wdt_stop, 449 .ping = iTCO_wdt_ping, 450 .set_timeout = iTCO_wdt_set_timeout, 451 .get_timeleft = iTCO_wdt_get_timeleft, 452 }; 453 454 /* 455 * Init & exit routines 456 */ 457 458 static int iTCO_wdt_probe(struct platform_device *pdev) 459 { 460 struct device *dev = &pdev->dev; 461 struct itco_wdt_platform_data *pdata = dev_get_platdata(dev); 462 struct iTCO_wdt_private *p; 463 unsigned long val32; 464 int ret; 465 466 if (!pdata) 467 return -ENODEV; 468 469 p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); 470 if (!p) 471 return -ENOMEM; 472 473 spin_lock_init(&p->io_lock); 474 475 p->tco_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_TCO); 476 if (!p->tco_res) 477 return -ENODEV; 478 479 p->iTCO_version = pdata->version; 480 p->pci_dev = to_pci_dev(dev->parent); 481 482 p->smi_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_SMI); 483 if (p->smi_res) { 484 /* The TCO logic uses the TCO_EN bit in the SMI_EN register */ 485 if (!devm_request_region(dev, p->smi_res->start, 486 resource_size(p->smi_res), 487 pdev->name)) { 488 dev_err(dev, "I/O address 0x%04llx already in use, device disabled\n", 489 (u64)SMI_EN(p)); 490 return -EBUSY; 491 } 492 } else if (iTCO_vendorsupport || 493 turn_SMI_watchdog_clear_off >= p->iTCO_version) { 494 dev_err(dev, "SMI I/O resource is missing\n"); 495 return -ENODEV; 496 } 497 498 iTCO_wdt_no_reboot_bit_setup(p, pdev, pdata); 499 500 /* 501 * Get the Memory-Mapped GCS or PMC register, we need it for the 502 * NO_REBOOT flag (TCO v2 and v3). 503 */ 504 if (p->iTCO_version >= 2 && p->iTCO_version < 6 && 505 !pdata->no_reboot_use_pmc) { 506 p->gcs_pmc_res = platform_get_resource(pdev, 507 IORESOURCE_MEM, 508 ICH_RES_MEM_GCS_PMC); 509 p->gcs_pmc = devm_ioremap_resource(dev, p->gcs_pmc_res); 510 if (IS_ERR(p->gcs_pmc)) 511 return PTR_ERR(p->gcs_pmc); 512 } 513 514 /* Check chipset's NO_REBOOT bit */ 515 if (p->update_no_reboot_bit(p->no_reboot_priv, false) && 516 iTCO_vendor_check_noreboot_on()) { 517 dev_info(dev, "unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n"); 518 return -ENODEV; /* Cannot reset NO_REBOOT bit */ 519 } 520 521 /* Set the NO_REBOOT bit to prevent later reboots, just for sure */ 522 p->update_no_reboot_bit(p->no_reboot_priv, true); 523 524 if (turn_SMI_watchdog_clear_off >= p->iTCO_version) { 525 /* 526 * Bit 13: TCO_EN -> 0 527 * Disables TCO logic generating an SMI# 528 */ 529 val32 = inl(SMI_EN(p)); 530 val32 &= ~TCO_EN; /* Turn off SMI clearing watchdog */ 531 outl(val32, SMI_EN(p)); 532 } 533 534 if (!devm_request_region(dev, p->tco_res->start, 535 resource_size(p->tco_res), 536 pdev->name)) { 537 dev_err(dev, "I/O address 0x%04llx already in use, device disabled\n", 538 (u64)TCOBASE(p)); 539 return -EBUSY; 540 } 541 542 dev_info(dev, "Found a %s TCO device (Version=%d, TCOBASE=0x%04llx)\n", 543 pdata->name, pdata->version, (u64)TCOBASE(p)); 544 545 /* Clear out the (probably old) status */ 546 switch (p->iTCO_version) { 547 case 6: 548 case 5: 549 case 4: 550 outw(0x0008, TCO1_STS(p)); /* Clear the Time Out Status bit */ 551 outw(0x0002, TCO2_STS(p)); /* Clear SECOND_TO_STS bit */ 552 break; 553 case 3: 554 outl(0x20008, TCO1_STS(p)); 555 break; 556 case 2: 557 case 1: 558 default: 559 outw(0x0008, TCO1_STS(p)); /* Clear the Time Out Status bit */ 560 outw(0x0002, TCO2_STS(p)); /* Clear SECOND_TO_STS bit */ 561 outw(0x0004, TCO2_STS(p)); /* Clear BOOT_STS bit */ 562 break; 563 } 564 565 p->wddev.info = &ident, 566 p->wddev.ops = &iTCO_wdt_ops, 567 p->wddev.bootstatus = 0; 568 p->wddev.timeout = WATCHDOG_TIMEOUT; 569 watchdog_set_nowayout(&p->wddev, nowayout); 570 p->wddev.parent = dev; 571 572 watchdog_set_drvdata(&p->wddev, p); 573 platform_set_drvdata(pdev, p); 574 575 /* Make sure the watchdog is not running */ 576 iTCO_wdt_stop(&p->wddev); 577 578 /* Check that the heartbeat value is within it's range; 579 if not reset to the default */ 580 if (iTCO_wdt_set_timeout(&p->wddev, heartbeat)) { 581 iTCO_wdt_set_timeout(&p->wddev, WATCHDOG_TIMEOUT); 582 dev_info(dev, "timeout value out of range, using %d\n", 583 WATCHDOG_TIMEOUT); 584 } 585 586 watchdog_stop_on_reboot(&p->wddev); 587 watchdog_stop_on_unregister(&p->wddev); 588 ret = devm_watchdog_register_device(dev, &p->wddev); 589 if (ret != 0) { 590 dev_err(dev, "cannot register watchdog device (err=%d)\n", ret); 591 return ret; 592 } 593 594 dev_info(dev, "initialized. heartbeat=%d sec (nowayout=%d)\n", 595 heartbeat, nowayout); 596 597 return 0; 598 } 599 600 #ifdef CONFIG_PM_SLEEP 601 /* 602 * Suspend-to-idle requires this, because it stops the ticks and timekeeping, so 603 * the watchdog cannot be pinged while in that state. In ACPI sleep states the 604 * watchdog is stopped by the platform firmware. 605 */ 606 607 #ifdef CONFIG_ACPI 608 static inline bool need_suspend(void) 609 { 610 return acpi_target_system_state() == ACPI_STATE_S0; 611 } 612 #else 613 static inline bool need_suspend(void) { return true; } 614 #endif 615 616 static int iTCO_wdt_suspend_noirq(struct device *dev) 617 { 618 struct iTCO_wdt_private *p = dev_get_drvdata(dev); 619 int ret = 0; 620 621 p->suspended = false; 622 if (watchdog_active(&p->wddev) && need_suspend()) { 623 ret = iTCO_wdt_stop(&p->wddev); 624 if (!ret) 625 p->suspended = true; 626 } 627 return ret; 628 } 629 630 static int iTCO_wdt_resume_noirq(struct device *dev) 631 { 632 struct iTCO_wdt_private *p = dev_get_drvdata(dev); 633 634 if (p->suspended) 635 iTCO_wdt_start(&p->wddev); 636 637 return 0; 638 } 639 640 static const struct dev_pm_ops iTCO_wdt_pm = { 641 .suspend_noirq = iTCO_wdt_suspend_noirq, 642 .resume_noirq = iTCO_wdt_resume_noirq, 643 }; 644 645 #define ITCO_WDT_PM_OPS (&iTCO_wdt_pm) 646 #else 647 #define ITCO_WDT_PM_OPS NULL 648 #endif /* CONFIG_PM_SLEEP */ 649 650 static struct platform_driver iTCO_wdt_driver = { 651 .probe = iTCO_wdt_probe, 652 .driver = { 653 .name = DRV_NAME, 654 .pm = ITCO_WDT_PM_OPS, 655 }, 656 }; 657 658 module_platform_driver(iTCO_wdt_driver); 659 660 MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>"); 661 MODULE_DESCRIPTION("Intel TCO WatchDog Timer Driver"); 662 MODULE_VERSION(DRV_VERSION); 663 MODULE_LICENSE("GPL"); 664 MODULE_ALIAS("platform:" DRV_NAME); 665