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 75 #define TCO_RLD(p) (TCOBASE(p) + 0x00) /* TCO Timer Reload/Curr. Value */ 76 #define TCOv1_TMR(p) (TCOBASE(p) + 0x01) /* TCOv1 Timer Initial Value*/ 77 #define TCO_DAT_IN(p) (TCOBASE(p) + 0x02) /* TCO Data In Register */ 78 #define TCO_DAT_OUT(p) (TCOBASE(p) + 0x03) /* TCO Data Out Register */ 79 #define TCO1_STS(p) (TCOBASE(p) + 0x04) /* TCO1 Status Register */ 80 #define TCO2_STS(p) (TCOBASE(p) + 0x06) /* TCO2 Status Register */ 81 #define TCO1_CNT(p) (TCOBASE(p) + 0x08) /* TCO1 Control Register */ 82 #define TCO2_CNT(p) (TCOBASE(p) + 0x0a) /* TCO2 Control Register */ 83 #define TCOv2_TMR(p) (TCOBASE(p) + 0x12) /* TCOv2 Timer Initial Value*/ 84 85 /* internal variables */ 86 struct iTCO_wdt_private { 87 struct watchdog_device wddev; 88 89 /* TCO version/generation */ 90 unsigned int iTCO_version; 91 struct resource *tco_res; 92 struct resource *smi_res; 93 /* 94 * NO_REBOOT flag is Memory-Mapped GCS register bit 5 (TCO version 2), 95 * or memory-mapped PMC register bit 4 (TCO version 3). 96 */ 97 unsigned long __iomem *gcs_pmc; 98 /* the lock for io operations */ 99 spinlock_t io_lock; 100 /* the PCI-device */ 101 struct pci_dev *pci_dev; 102 /* whether or not the watchdog has been suspended */ 103 bool suspended; 104 /* no reboot API private data */ 105 void *no_reboot_priv; 106 /* no reboot update function pointer */ 107 int (*update_no_reboot_bit)(void *p, bool set); 108 }; 109 110 /* module parameters */ 111 #define WATCHDOG_TIMEOUT 30 /* 30 sec default heartbeat */ 112 static int heartbeat = WATCHDOG_TIMEOUT; /* in seconds */ 113 module_param(heartbeat, int, 0); 114 MODULE_PARM_DESC(heartbeat, "Watchdog timeout in seconds. " 115 "5..76 (TCO v1) or 3..614 (TCO v2), default=" 116 __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); 117 118 static bool nowayout = WATCHDOG_NOWAYOUT; 119 module_param(nowayout, bool, 0); 120 MODULE_PARM_DESC(nowayout, 121 "Watchdog cannot be stopped once started (default=" 122 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 123 124 static int turn_SMI_watchdog_clear_off = 1; 125 module_param(turn_SMI_watchdog_clear_off, int, 0); 126 MODULE_PARM_DESC(turn_SMI_watchdog_clear_off, 127 "Turn off SMI clearing watchdog (depends on TCO-version)(default=1)"); 128 129 /* 130 * Some TCO specific functions 131 */ 132 133 /* 134 * The iTCO v1 and v2's internal timer is stored as ticks which decrement 135 * every 0.6 seconds. v3's internal timer is stored as seconds (some 136 * datasheets incorrectly state 0.6 seconds). 137 */ 138 static inline unsigned int seconds_to_ticks(struct iTCO_wdt_private *p, 139 int secs) 140 { 141 return p->iTCO_version == 3 ? secs : (secs * 10) / 6; 142 } 143 144 static inline unsigned int ticks_to_seconds(struct iTCO_wdt_private *p, 145 int ticks) 146 { 147 return p->iTCO_version == 3 ? ticks : (ticks * 6) / 10; 148 } 149 150 static inline u32 no_reboot_bit(struct iTCO_wdt_private *p) 151 { 152 u32 enable_bit; 153 154 switch (p->iTCO_version) { 155 case 5: 156 case 3: 157 enable_bit = 0x00000010; 158 break; 159 case 2: 160 enable_bit = 0x00000020; 161 break; 162 case 4: 163 case 1: 164 default: 165 enable_bit = 0x00000002; 166 break; 167 } 168 169 return enable_bit; 170 } 171 172 static int update_no_reboot_bit_def(void *priv, bool set) 173 { 174 return 0; 175 } 176 177 static int update_no_reboot_bit_pci(void *priv, bool set) 178 { 179 struct iTCO_wdt_private *p = priv; 180 u32 val32 = 0, newval32 = 0; 181 182 pci_read_config_dword(p->pci_dev, 0xd4, &val32); 183 if (set) 184 val32 |= no_reboot_bit(p); 185 else 186 val32 &= ~no_reboot_bit(p); 187 pci_write_config_dword(p->pci_dev, 0xd4, val32); 188 pci_read_config_dword(p->pci_dev, 0xd4, &newval32); 189 190 /* make sure the update is successful */ 191 if (val32 != newval32) 192 return -EIO; 193 194 return 0; 195 } 196 197 static int update_no_reboot_bit_mem(void *priv, bool set) 198 { 199 struct iTCO_wdt_private *p = priv; 200 u32 val32 = 0, newval32 = 0; 201 202 val32 = readl(p->gcs_pmc); 203 if (set) 204 val32 |= no_reboot_bit(p); 205 else 206 val32 &= ~no_reboot_bit(p); 207 writel(val32, p->gcs_pmc); 208 newval32 = readl(p->gcs_pmc); 209 210 /* make sure the update is successful */ 211 if (val32 != newval32) 212 return -EIO; 213 214 return 0; 215 } 216 217 static int update_no_reboot_bit_cnt(void *priv, bool set) 218 { 219 struct iTCO_wdt_private *p = priv; 220 u16 val, newval; 221 222 val = inw(TCO1_CNT(p)); 223 if (set) 224 val |= BIT(0); 225 else 226 val &= ~BIT(0); 227 outw(val, TCO1_CNT(p)); 228 newval = inw(TCO1_CNT(p)); 229 230 /* make sure the update is successful */ 231 return val != newval ? -EIO : 0; 232 } 233 234 static int update_no_reboot_bit_pmc(void *priv, bool set) 235 { 236 struct intel_pmc_dev *pmc = priv; 237 u32 bits = PMC_CFG_NO_REBOOT_EN; 238 u32 value = set ? bits : 0; 239 240 return intel_pmc_gcr_update(pmc, PMC_GCR_PMC_CFG_REG, bits, value); 241 } 242 243 static void iTCO_wdt_no_reboot_bit_setup(struct iTCO_wdt_private *p, 244 struct platform_device *pdev, 245 struct itco_wdt_platform_data *pdata) 246 { 247 if (pdata->no_reboot_use_pmc) { 248 struct intel_pmc_dev *pmc = dev_get_drvdata(pdev->dev.parent); 249 250 p->update_no_reboot_bit = update_no_reboot_bit_pmc; 251 p->no_reboot_priv = pmc; 252 return; 253 } 254 255 if (p->iTCO_version >= 6) 256 p->update_no_reboot_bit = update_no_reboot_bit_cnt; 257 else if (p->iTCO_version >= 2) 258 p->update_no_reboot_bit = update_no_reboot_bit_mem; 259 else if (p->iTCO_version == 1) 260 p->update_no_reboot_bit = update_no_reboot_bit_pci; 261 else 262 p->update_no_reboot_bit = update_no_reboot_bit_def; 263 264 p->no_reboot_priv = p; 265 } 266 267 static int iTCO_wdt_start(struct watchdog_device *wd_dev) 268 { 269 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 270 unsigned int val; 271 272 spin_lock(&p->io_lock); 273 274 iTCO_vendor_pre_start(p->smi_res, wd_dev->timeout); 275 276 /* disable chipset's NO_REBOOT bit */ 277 if (p->update_no_reboot_bit(p->no_reboot_priv, false)) { 278 spin_unlock(&p->io_lock); 279 dev_err(wd_dev->parent, "failed to reset NO_REBOOT flag, reboot disabled by hardware/BIOS\n"); 280 return -EIO; 281 } 282 283 /* Force the timer to its reload value by writing to the TCO_RLD 284 register */ 285 if (p->iTCO_version >= 2) 286 outw(0x01, TCO_RLD(p)); 287 else if (p->iTCO_version == 1) 288 outb(0x01, TCO_RLD(p)); 289 290 /* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled to count */ 291 val = inw(TCO1_CNT(p)); 292 val &= 0xf7ff; 293 outw(val, TCO1_CNT(p)); 294 val = inw(TCO1_CNT(p)); 295 spin_unlock(&p->io_lock); 296 297 if (val & 0x0800) 298 return -1; 299 return 0; 300 } 301 302 static int iTCO_wdt_stop(struct watchdog_device *wd_dev) 303 { 304 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 305 unsigned int val; 306 307 spin_lock(&p->io_lock); 308 309 iTCO_vendor_pre_stop(p->smi_res); 310 311 /* Bit 11: TCO Timer Halt -> 1 = The TCO timer is disabled */ 312 val = inw(TCO1_CNT(p)); 313 val |= 0x0800; 314 outw(val, TCO1_CNT(p)); 315 val = inw(TCO1_CNT(p)); 316 317 /* Set the NO_REBOOT bit to prevent later reboots, just for sure */ 318 p->update_no_reboot_bit(p->no_reboot_priv, true); 319 320 spin_unlock(&p->io_lock); 321 322 if ((val & 0x0800) == 0) 323 return -1; 324 return 0; 325 } 326 327 static int iTCO_wdt_ping(struct watchdog_device *wd_dev) 328 { 329 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 330 331 spin_lock(&p->io_lock); 332 333 /* Reload the timer by writing to the TCO Timer Counter register */ 334 if (p->iTCO_version >= 2) { 335 outw(0x01, TCO_RLD(p)); 336 } else if (p->iTCO_version == 1) { 337 /* Reset the timeout status bit so that the timer 338 * needs to count down twice again before rebooting */ 339 outw(0x0008, TCO1_STS(p)); /* write 1 to clear bit */ 340 341 outb(0x01, TCO_RLD(p)); 342 } 343 344 spin_unlock(&p->io_lock); 345 return 0; 346 } 347 348 static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t) 349 { 350 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 351 unsigned int val16; 352 unsigned char val8; 353 unsigned int tmrval; 354 355 tmrval = seconds_to_ticks(p, t); 356 357 /* For TCO v1 the timer counts down twice before rebooting */ 358 if (p->iTCO_version == 1) 359 tmrval /= 2; 360 361 /* from the specs: */ 362 /* "Values of 0h-3h are ignored and should not be attempted" */ 363 if (tmrval < 0x04) 364 return -EINVAL; 365 if ((p->iTCO_version >= 2 && tmrval > 0x3ff) || 366 (p->iTCO_version == 1 && tmrval > 0x03f)) 367 return -EINVAL; 368 369 /* Write new heartbeat to watchdog */ 370 if (p->iTCO_version >= 2) { 371 spin_lock(&p->io_lock); 372 val16 = inw(TCOv2_TMR(p)); 373 val16 &= 0xfc00; 374 val16 |= tmrval; 375 outw(val16, TCOv2_TMR(p)); 376 val16 = inw(TCOv2_TMR(p)); 377 spin_unlock(&p->io_lock); 378 379 if ((val16 & 0x3ff) != tmrval) 380 return -EINVAL; 381 } else if (p->iTCO_version == 1) { 382 spin_lock(&p->io_lock); 383 val8 = inb(TCOv1_TMR(p)); 384 val8 &= 0xc0; 385 val8 |= (tmrval & 0xff); 386 outb(val8, TCOv1_TMR(p)); 387 val8 = inb(TCOv1_TMR(p)); 388 spin_unlock(&p->io_lock); 389 390 if ((val8 & 0x3f) != tmrval) 391 return -EINVAL; 392 } 393 394 wd_dev->timeout = t; 395 return 0; 396 } 397 398 static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev) 399 { 400 struct iTCO_wdt_private *p = watchdog_get_drvdata(wd_dev); 401 unsigned int val16; 402 unsigned char val8; 403 unsigned int time_left = 0; 404 405 /* read the TCO Timer */ 406 if (p->iTCO_version >= 2) { 407 spin_lock(&p->io_lock); 408 val16 = inw(TCO_RLD(p)); 409 val16 &= 0x3ff; 410 spin_unlock(&p->io_lock); 411 412 time_left = ticks_to_seconds(p, val16); 413 } else if (p->iTCO_version == 1) { 414 spin_lock(&p->io_lock); 415 val8 = inb(TCO_RLD(p)); 416 val8 &= 0x3f; 417 if (!(inw(TCO1_STS(p)) & 0x0008)) 418 val8 += (inb(TCOv1_TMR(p)) & 0x3f); 419 spin_unlock(&p->io_lock); 420 421 time_left = ticks_to_seconds(p, val8); 422 } 423 return time_left; 424 } 425 426 /* Returns true if the watchdog was running */ 427 static bool iTCO_wdt_set_running(struct iTCO_wdt_private *p) 428 { 429 u16 val; 430 431 /* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled */ 432 val = inw(TCO1_CNT(p)); 433 if (!(val & BIT(11))) { 434 set_bit(WDOG_HW_RUNNING, &p->wddev.status); 435 return true; 436 } 437 return false; 438 } 439 440 /* 441 * Kernel Interfaces 442 */ 443 444 static struct watchdog_info ident = { 445 .options = WDIOF_SETTIMEOUT | 446 WDIOF_KEEPALIVEPING | 447 WDIOF_MAGICCLOSE, 448 .identity = DRV_NAME, 449 }; 450 451 static const struct watchdog_ops iTCO_wdt_ops = { 452 .owner = THIS_MODULE, 453 .start = iTCO_wdt_start, 454 .stop = iTCO_wdt_stop, 455 .ping = iTCO_wdt_ping, 456 .set_timeout = iTCO_wdt_set_timeout, 457 .get_timeleft = iTCO_wdt_get_timeleft, 458 }; 459 460 /* 461 * Init & exit routines 462 */ 463 464 static int iTCO_wdt_probe(struct platform_device *pdev) 465 { 466 struct device *dev = &pdev->dev; 467 struct itco_wdt_platform_data *pdata = dev_get_platdata(dev); 468 struct iTCO_wdt_private *p; 469 unsigned long val32; 470 int ret; 471 472 if (!pdata) 473 return -ENODEV; 474 475 p = devm_kzalloc(dev, sizeof(*p), GFP_KERNEL); 476 if (!p) 477 return -ENOMEM; 478 479 spin_lock_init(&p->io_lock); 480 481 p->tco_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_TCO); 482 if (!p->tco_res) 483 return -ENODEV; 484 485 p->iTCO_version = pdata->version; 486 p->pci_dev = to_pci_dev(dev->parent); 487 488 p->smi_res = platform_get_resource(pdev, IORESOURCE_IO, ICH_RES_IO_SMI); 489 if (p->smi_res) { 490 /* The TCO logic uses the TCO_EN bit in the SMI_EN register */ 491 if (!devm_request_region(dev, p->smi_res->start, 492 resource_size(p->smi_res), 493 pdev->name)) { 494 dev_err(dev, "I/O address 0x%04llx already in use, device disabled\n", 495 (u64)SMI_EN(p)); 496 return -EBUSY; 497 } 498 } else if (iTCO_vendorsupport || 499 turn_SMI_watchdog_clear_off >= p->iTCO_version) { 500 dev_err(dev, "SMI I/O resource is missing\n"); 501 return -ENODEV; 502 } 503 504 iTCO_wdt_no_reboot_bit_setup(p, pdev, pdata); 505 506 /* 507 * Get the Memory-Mapped GCS or PMC register, we need it for the 508 * NO_REBOOT flag (TCO v2 and v3). 509 */ 510 if (p->iTCO_version >= 2 && p->iTCO_version < 6 && 511 !pdata->no_reboot_use_pmc) { 512 p->gcs_pmc = devm_platform_ioremap_resource(pdev, ICH_RES_MEM_GCS_PMC); 513 if (IS_ERR(p->gcs_pmc)) 514 return PTR_ERR(p->gcs_pmc); 515 } 516 517 /* Check chipset's NO_REBOOT bit */ 518 if (p->update_no_reboot_bit(p->no_reboot_priv, false) && 519 iTCO_vendor_check_noreboot_on()) { 520 dev_info(dev, "unable to reset NO_REBOOT flag, device disabled by hardware/BIOS\n"); 521 return -ENODEV; /* Cannot reset NO_REBOOT bit */ 522 } 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 &= 0xffffdfff; /* 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 ident.firmware_version = p->iTCO_version; 566 p->wddev.info = &ident; 567 p->wddev.ops = &iTCO_wdt_ops; 568 p->wddev.bootstatus = 0; 569 p->wddev.timeout = WATCHDOG_TIMEOUT; 570 watchdog_set_nowayout(&p->wddev, nowayout); 571 p->wddev.parent = dev; 572 573 watchdog_set_drvdata(&p->wddev, p); 574 platform_set_drvdata(pdev, p); 575 576 if (!iTCO_wdt_set_running(p)) { 577 /* 578 * If the watchdog was not running set NO_REBOOT now to 579 * prevent later reboots. 580 */ 581 p->update_no_reboot_bit(p->no_reboot_priv, true); 582 } 583 584 /* Check that the heartbeat value is within it's range; 585 if not reset to the default */ 586 if (iTCO_wdt_set_timeout(&p->wddev, heartbeat)) { 587 iTCO_wdt_set_timeout(&p->wddev, WATCHDOG_TIMEOUT); 588 dev_info(dev, "timeout value out of range, using %d\n", 589 WATCHDOG_TIMEOUT); 590 } 591 592 watchdog_stop_on_reboot(&p->wddev); 593 watchdog_stop_on_unregister(&p->wddev); 594 ret = devm_watchdog_register_device(dev, &p->wddev); 595 if (ret != 0) { 596 dev_err(dev, "cannot register watchdog device (err=%d)\n", ret); 597 return ret; 598 } 599 600 dev_info(dev, "initialized. heartbeat=%d sec (nowayout=%d)\n", 601 heartbeat, nowayout); 602 603 return 0; 604 } 605 606 /* 607 * Suspend-to-idle requires this, because it stops the ticks and timekeeping, so 608 * the watchdog cannot be pinged while in that state. In ACPI sleep states the 609 * watchdog is stopped by the platform firmware. 610 */ 611 612 #ifdef CONFIG_ACPI 613 static inline bool __maybe_unused need_suspend(void) 614 { 615 return acpi_target_system_state() == ACPI_STATE_S0; 616 } 617 #else 618 static inline bool __maybe_unused need_suspend(void) { return true; } 619 #endif 620 621 static int __maybe_unused iTCO_wdt_suspend_noirq(struct device *dev) 622 { 623 struct iTCO_wdt_private *p = dev_get_drvdata(dev); 624 int ret = 0; 625 626 p->suspended = false; 627 if (watchdog_active(&p->wddev) && need_suspend()) { 628 ret = iTCO_wdt_stop(&p->wddev); 629 if (!ret) 630 p->suspended = true; 631 } 632 return ret; 633 } 634 635 static int __maybe_unused iTCO_wdt_resume_noirq(struct device *dev) 636 { 637 struct iTCO_wdt_private *p = dev_get_drvdata(dev); 638 639 if (p->suspended) 640 iTCO_wdt_start(&p->wddev); 641 642 return 0; 643 } 644 645 static const struct dev_pm_ops iTCO_wdt_pm = { 646 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(iTCO_wdt_suspend_noirq, 647 iTCO_wdt_resume_noirq) 648 }; 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, 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