1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * A hwmon driver for ACPI 4.0 power meters 4 * Copyright (C) 2009 IBM 5 * 6 * Author: Darrick J. Wong <darrick.wong@oracle.com> 7 */ 8 9 #include <linux/module.h> 10 #include <linux/hwmon.h> 11 #include <linux/hwmon-sysfs.h> 12 #include <linux/jiffies.h> 13 #include <linux/mutex.h> 14 #include <linux/dmi.h> 15 #include <linux/slab.h> 16 #include <linux/kdev_t.h> 17 #include <linux/sched.h> 18 #include <linux/time.h> 19 #include <linux/err.h> 20 #include <linux/acpi.h> 21 22 #define ACPI_POWER_METER_NAME "power_meter" 23 #define ACPI_POWER_METER_DEVICE_NAME "Power Meter" 24 #define ACPI_POWER_METER_CLASS "pwr_meter_resource" 25 26 #define NUM_SENSORS 17 27 28 #define POWER_METER_CAN_MEASURE (1 << 0) 29 #define POWER_METER_CAN_TRIP (1 << 1) 30 #define POWER_METER_CAN_CAP (1 << 2) 31 #define POWER_METER_CAN_NOTIFY (1 << 3) 32 #define POWER_METER_IS_BATTERY (1 << 8) 33 #define UNKNOWN_HYSTERESIS 0xFFFFFFFF 34 #define UNKNOWN_POWER 0xFFFFFFFF 35 36 #define METER_NOTIFY_CONFIG 0x80 37 #define METER_NOTIFY_TRIP 0x81 38 #define METER_NOTIFY_CAP 0x82 39 #define METER_NOTIFY_CAPPING 0x83 40 #define METER_NOTIFY_INTERVAL 0x84 41 42 #define POWER_AVERAGE_NAME "power1_average" 43 #define POWER_CAP_NAME "power1_cap" 44 #define POWER_AVG_INTERVAL_NAME "power1_average_interval" 45 #define POWER_ALARM_NAME "power1_alarm" 46 47 static int cap_in_hardware; 48 static bool force_cap_on; 49 50 static int can_cap_in_hardware(void) 51 { 52 return force_cap_on || cap_in_hardware; 53 } 54 55 static const struct acpi_device_id power_meter_ids[] = { 56 {"ACPI000D", 0}, 57 {"", 0}, 58 }; 59 MODULE_DEVICE_TABLE(acpi, power_meter_ids); 60 61 struct acpi_power_meter_capabilities { 62 u64 flags; 63 u64 units; 64 u64 type; 65 u64 accuracy; 66 u64 sampling_time; 67 u64 min_avg_interval; 68 u64 max_avg_interval; 69 u64 hysteresis; 70 u64 configurable_cap; 71 u64 min_cap; 72 u64 max_cap; 73 }; 74 75 struct acpi_power_meter_resource { 76 struct acpi_device *acpi_dev; 77 acpi_bus_id name; 78 struct mutex lock; 79 struct device *hwmon_dev; 80 struct acpi_power_meter_capabilities caps; 81 acpi_string model_number; 82 acpi_string serial_number; 83 acpi_string oem_info; 84 u64 power; 85 u64 cap; 86 u64 avg_interval; 87 bool power_alarm; 88 int sensors_valid; 89 unsigned long sensors_last_updated; 90 #define POWER_METER_TRIP_AVERAGE_MIN_IDX 0 91 #define POWER_METER_TRIP_AVERAGE_MAX_IDX 1 92 s64 trip[2]; 93 int num_domain_devices; 94 struct acpi_device **domain_devices; 95 struct kobject *holders_dir; 96 }; 97 98 /* Averaging interval */ 99 static int update_avg_interval(struct acpi_power_meter_resource *resource) 100 { 101 unsigned long long data; 102 acpi_status status; 103 104 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GAI", 105 NULL, &data); 106 if (ACPI_FAILURE(status)) { 107 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GAI", 108 status); 109 return -ENODEV; 110 } 111 112 resource->avg_interval = data; 113 return 0; 114 } 115 116 /* Cap functions */ 117 static int update_cap(struct acpi_power_meter_resource *resource) 118 { 119 unsigned long long data; 120 acpi_status status; 121 122 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GHL", 123 NULL, &data); 124 if (ACPI_FAILURE(status)) { 125 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_GHL", 126 status); 127 return -ENODEV; 128 } 129 130 resource->cap = data; 131 return 0; 132 } 133 134 /* Power meter trip points */ 135 static int set_acpi_trip(struct acpi_power_meter_resource *resource) 136 { 137 union acpi_object arg_objs[] = { 138 {ACPI_TYPE_INTEGER}, 139 {ACPI_TYPE_INTEGER} 140 }; 141 struct acpi_object_list args = { 2, arg_objs }; 142 unsigned long long data; 143 acpi_status status; 144 145 /* Both trip levels must be set */ 146 if (resource->trip[0] < 0 || resource->trip[1] < 0) 147 return 0; 148 149 /* This driver stores min, max; ACPI wants max, min. */ 150 arg_objs[0].integer.value = resource->trip[1]; 151 arg_objs[1].integer.value = resource->trip[0]; 152 153 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PTP", 154 &args, &data); 155 if (ACPI_FAILURE(status)) { 156 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PTP", 157 status); 158 return -EINVAL; 159 } 160 161 /* _PTP returns 0 on success, nonzero otherwise */ 162 if (data) 163 return -EINVAL; 164 165 return 0; 166 } 167 168 /* Power meter */ 169 static int update_meter(struct acpi_power_meter_resource *resource) 170 { 171 unsigned long long data; 172 acpi_status status; 173 unsigned long local_jiffies = jiffies; 174 175 if (time_before(local_jiffies, resource->sensors_last_updated + 176 msecs_to_jiffies(resource->caps.sampling_time)) && 177 resource->sensors_valid) 178 return 0; 179 180 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PMM", 181 NULL, &data); 182 if (ACPI_FAILURE(status)) { 183 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMM", 184 status); 185 return -ENODEV; 186 } 187 188 resource->power = data; 189 resource->sensors_valid = 1; 190 resource->sensors_last_updated = jiffies; 191 return 0; 192 } 193 194 /* Read power domain data */ 195 static void remove_domain_devices(struct acpi_power_meter_resource *resource) 196 { 197 int i; 198 199 if (!resource->num_domain_devices) 200 return; 201 202 for (i = 0; i < resource->num_domain_devices; i++) { 203 struct acpi_device *obj = resource->domain_devices[i]; 204 205 if (!obj) 206 continue; 207 208 sysfs_remove_link(resource->holders_dir, 209 kobject_name(&obj->dev.kobj)); 210 acpi_dev_put(obj); 211 } 212 213 kfree(resource->domain_devices); 214 kobject_put(resource->holders_dir); 215 resource->num_domain_devices = 0; 216 } 217 218 static int read_domain_devices(struct acpi_power_meter_resource *resource) 219 { 220 int res = 0; 221 int i; 222 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 223 union acpi_object *pss; 224 acpi_status status; 225 226 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMD", NULL, 227 &buffer); 228 if (ACPI_FAILURE(status)) { 229 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMD", 230 status); 231 return -ENODEV; 232 } 233 234 pss = buffer.pointer; 235 if (!pss || 236 pss->type != ACPI_TYPE_PACKAGE) { 237 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME 238 "Invalid _PMD data\n"); 239 res = -EFAULT; 240 goto end; 241 } 242 243 if (!pss->package.count) 244 goto end; 245 246 resource->domain_devices = kcalloc(pss->package.count, 247 sizeof(struct acpi_device *), 248 GFP_KERNEL); 249 if (!resource->domain_devices) { 250 res = -ENOMEM; 251 goto end; 252 } 253 254 resource->holders_dir = kobject_create_and_add("measures", 255 &resource->acpi_dev->dev.kobj); 256 if (!resource->holders_dir) { 257 res = -ENOMEM; 258 goto exit_free; 259 } 260 261 resource->num_domain_devices = pss->package.count; 262 263 for (i = 0; i < pss->package.count; i++) { 264 struct acpi_device *obj; 265 union acpi_object *element = &pss->package.elements[i]; 266 267 /* Refuse non-references */ 268 if (element->type != ACPI_TYPE_LOCAL_REFERENCE) 269 continue; 270 271 /* Create a symlink to domain objects */ 272 obj = acpi_get_acpi_dev(element->reference.handle); 273 resource->domain_devices[i] = obj; 274 if (!obj) 275 continue; 276 277 res = sysfs_create_link(resource->holders_dir, &obj->dev.kobj, 278 kobject_name(&obj->dev.kobj)); 279 if (res) { 280 acpi_dev_put(obj); 281 resource->domain_devices[i] = NULL; 282 } 283 } 284 285 res = 0; 286 goto end; 287 288 exit_free: 289 kfree(resource->domain_devices); 290 end: 291 kfree(buffer.pointer); 292 return res; 293 } 294 295 static int set_trip(struct acpi_power_meter_resource *resource, u16 trip_idx, 296 unsigned long trip) 297 { 298 unsigned long trip_bk; 299 int ret; 300 301 trip = DIV_ROUND_CLOSEST(trip, 1000); 302 trip_bk = resource->trip[trip_idx]; 303 304 resource->trip[trip_idx] = trip; 305 ret = set_acpi_trip(resource); 306 if (ret) { 307 dev_err(&resource->acpi_dev->dev, "set %s failed.\n", 308 (trip_idx == POWER_METER_TRIP_AVERAGE_MIN_IDX) ? 309 "power1_average_min" : "power1_average_max"); 310 resource->trip[trip_idx] = trip_bk; 311 } 312 313 return ret; 314 } 315 316 static int set_cap(struct acpi_power_meter_resource *resource, 317 unsigned long cap) 318 { 319 union acpi_object arg0 = { ACPI_TYPE_INTEGER }; 320 struct acpi_object_list args = { 1, &arg0 }; 321 unsigned long long data; 322 acpi_status status; 323 324 cap = DIV_ROUND_CLOSEST(cap, 1000); 325 if (cap > resource->caps.max_cap || cap < resource->caps.min_cap) 326 return -EINVAL; 327 328 arg0.integer.value = cap; 329 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_SHL", 330 &args, &data); 331 if (ACPI_FAILURE(status)) { 332 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_SHL", 333 status); 334 return -EINVAL; 335 } 336 resource->cap = cap; 337 338 /* _SHL returns 0 on success, nonzero otherwise */ 339 if (data) 340 return -EINVAL; 341 342 return 0; 343 } 344 345 static int set_avg_interval(struct acpi_power_meter_resource *resource, 346 unsigned long val) 347 { 348 union acpi_object arg0 = { ACPI_TYPE_INTEGER }; 349 struct acpi_object_list args = { 1, &arg0 }; 350 unsigned long long data; 351 acpi_status status; 352 353 if (val > resource->caps.max_avg_interval || 354 val < resource->caps.min_avg_interval) 355 return -EINVAL; 356 357 arg0.integer.value = val; 358 status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PAI", 359 &args, &data); 360 if (ACPI_FAILURE(status)) { 361 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PAI", 362 status); 363 return -EINVAL; 364 } 365 resource->avg_interval = val; 366 367 /* _PAI returns 0 on success, nonzero otherwise */ 368 if (data) 369 return -EINVAL; 370 371 return 0; 372 } 373 374 static int get_power_alarm_state(struct acpi_power_meter_resource *resource, 375 long *val) 376 { 377 int ret; 378 379 ret = update_meter(resource); 380 if (ret) 381 return ret; 382 383 /* need to update cap if not to support the notification. */ 384 if (!(resource->caps.flags & POWER_METER_CAN_NOTIFY)) { 385 ret = update_cap(resource); 386 if (ret) 387 return ret; 388 resource->power_alarm = resource->power > resource->cap; 389 *val = resource->power_alarm; 390 } else { 391 *val = resource->power_alarm || resource->power > resource->cap; 392 resource->power_alarm = resource->power > resource->cap; 393 } 394 395 return 0; 396 } 397 398 static umode_t power_meter_is_visible(const void *data, 399 enum hwmon_sensor_types type, 400 u32 attr, int channel) 401 { 402 const struct acpi_power_meter_resource *res = data; 403 404 if (type != hwmon_power) 405 return 0; 406 407 switch (attr) { 408 case hwmon_power_average: 409 case hwmon_power_average_interval_min: 410 case hwmon_power_average_interval_max: 411 if (res->caps.flags & POWER_METER_CAN_MEASURE) 412 return 0444; 413 break; 414 case hwmon_power_average_interval: 415 if (res->caps.flags & POWER_METER_CAN_MEASURE) 416 return 0644; 417 break; 418 case hwmon_power_cap_min: 419 case hwmon_power_cap_max: 420 case hwmon_power_alarm: 421 if (res->caps.flags & POWER_METER_CAN_CAP && can_cap_in_hardware()) 422 return 0444; 423 break; 424 case hwmon_power_cap: 425 if (res->caps.flags & POWER_METER_CAN_CAP && can_cap_in_hardware()) { 426 if (res->caps.configurable_cap) 427 return 0644; 428 else 429 return 0444; 430 } 431 break; 432 default: 433 break; 434 } 435 436 return 0; 437 } 438 439 static int power_meter_read(struct device *dev, enum hwmon_sensor_types type, 440 u32 attr, int channel, long *val) 441 { 442 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 443 int ret = 0; 444 445 if (type != hwmon_power) 446 return -EINVAL; 447 448 guard(mutex)(&res->lock); 449 450 switch (attr) { 451 case hwmon_power_average: 452 ret = update_meter(res); 453 if (ret) 454 return ret; 455 if (res->power == UNKNOWN_POWER) 456 return -ENODATA; 457 *val = res->power * 1000; 458 break; 459 case hwmon_power_average_interval_min: 460 *val = res->caps.min_avg_interval; 461 break; 462 case hwmon_power_average_interval_max: 463 *val = res->caps.max_avg_interval; 464 break; 465 case hwmon_power_average_interval: 466 ret = update_avg_interval(res); 467 if (ret) 468 return ret; 469 *val = (res)->avg_interval; 470 break; 471 case hwmon_power_cap_min: 472 *val = res->caps.min_cap * 1000; 473 break; 474 case hwmon_power_cap_max: 475 *val = res->caps.max_cap * 1000; 476 break; 477 case hwmon_power_alarm: 478 ret = get_power_alarm_state(res, val); 479 if (ret) 480 return ret; 481 break; 482 case hwmon_power_cap: 483 ret = update_cap(res); 484 if (ret) 485 return ret; 486 *val = res->cap * 1000; 487 break; 488 default: 489 break; 490 } 491 492 return 0; 493 } 494 495 static int power_meter_write(struct device *dev, enum hwmon_sensor_types type, 496 u32 attr, int channel, long val) 497 { 498 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 499 int ret; 500 501 if (type != hwmon_power) 502 return -EINVAL; 503 504 guard(mutex)(&res->lock); 505 switch (attr) { 506 case hwmon_power_cap: 507 ret = set_cap(res, val); 508 break; 509 case hwmon_power_average_interval: 510 ret = set_avg_interval(res, val); 511 break; 512 default: 513 ret = -EOPNOTSUPP; 514 } 515 516 return ret; 517 } 518 519 static const struct hwmon_channel_info * const power_meter_info[] = { 520 HWMON_CHANNEL_INFO(power, HWMON_P_AVERAGE | 521 HWMON_P_AVERAGE_INTERVAL | HWMON_P_AVERAGE_INTERVAL_MIN | 522 HWMON_P_AVERAGE_INTERVAL_MAX | HWMON_P_CAP | HWMON_P_CAP_MIN | 523 HWMON_P_CAP_MAX | HWMON_P_ALARM), 524 NULL 525 }; 526 527 static const struct hwmon_ops power_meter_ops = { 528 .is_visible = power_meter_is_visible, 529 .read = power_meter_read, 530 .write = power_meter_write, 531 }; 532 533 static const struct hwmon_chip_info power_meter_chip_info = { 534 .ops = &power_meter_ops, 535 .info = power_meter_info, 536 }; 537 538 static ssize_t power1_average_max_store(struct device *dev, 539 struct device_attribute *attr, 540 const char *buf, size_t count) 541 { 542 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 543 unsigned long trip; 544 int ret; 545 546 ret = kstrtoul(buf, 10, &trip); 547 if (ret) 548 return ret; 549 550 mutex_lock(&res->lock); 551 ret = set_trip(res, POWER_METER_TRIP_AVERAGE_MAX_IDX, trip); 552 mutex_unlock(&res->lock); 553 554 return ret == 0 ? count : ret; 555 } 556 557 static ssize_t power1_average_min_store(struct device *dev, 558 struct device_attribute *attr, 559 const char *buf, size_t count) 560 { 561 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 562 unsigned long trip; 563 int ret; 564 565 ret = kstrtoul(buf, 10, &trip); 566 if (ret) 567 return ret; 568 569 mutex_lock(&res->lock); 570 ret = set_trip(res, POWER_METER_TRIP_AVERAGE_MIN_IDX, trip); 571 mutex_unlock(&res->lock); 572 573 return ret == 0 ? count : ret; 574 } 575 576 static ssize_t power1_average_min_show(struct device *dev, 577 struct device_attribute *attr, char *buf) 578 { 579 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 580 581 if (res->trip[POWER_METER_TRIP_AVERAGE_MIN_IDX] < 0) 582 return sysfs_emit(buf, "unknown\n"); 583 584 return sysfs_emit(buf, "%lld\n", 585 res->trip[POWER_METER_TRIP_AVERAGE_MIN_IDX] * 1000); 586 } 587 588 static ssize_t power1_average_max_show(struct device *dev, 589 struct device_attribute *attr, char *buf) 590 { 591 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 592 593 if (res->trip[POWER_METER_TRIP_AVERAGE_MAX_IDX] < 0) 594 return sysfs_emit(buf, "unknown\n"); 595 596 return sysfs_emit(buf, "%lld\n", 597 res->trip[POWER_METER_TRIP_AVERAGE_MAX_IDX] * 1000); 598 } 599 600 static ssize_t power1_cap_hyst_show(struct device *dev, 601 struct device_attribute *attr, char *buf) 602 { 603 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 604 605 if (res->caps.hysteresis == UNKNOWN_HYSTERESIS) 606 return sysfs_emit(buf, "unknown\n"); 607 608 return sysfs_emit(buf, "%llu\n", res->caps.hysteresis * 1000); 609 } 610 611 static ssize_t power1_accuracy_show(struct device *dev, 612 struct device_attribute *attr, 613 char *buf) 614 { 615 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 616 unsigned int acc = res->caps.accuracy; 617 618 return sysfs_emit(buf, "%u.%u%%\n", acc / 1000, acc % 1000); 619 } 620 621 static ssize_t power1_is_battery_show(struct device *dev, 622 struct device_attribute *attr, 623 char *buf) 624 { 625 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 626 627 return sysfs_emit(buf, "%u\n", 628 res->caps.flags & POWER_METER_IS_BATTERY ? 1 : 0); 629 } 630 631 static ssize_t power1_model_number_show(struct device *dev, 632 struct device_attribute *attr, 633 char *buf) 634 { 635 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 636 637 return sysfs_emit(buf, "%s\n", res->model_number); 638 } 639 640 static ssize_t power1_oem_info_show(struct device *dev, 641 struct device_attribute *attr, 642 char *buf) 643 { 644 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 645 646 return sysfs_emit(buf, "%s\n", res->oem_info); 647 } 648 649 static ssize_t power1_serial_number_show(struct device *dev, 650 struct device_attribute *attr, 651 char *buf) 652 { 653 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 654 655 return sysfs_emit(buf, "%s\n", res->serial_number); 656 } 657 658 /* depend on POWER_METER_CAN_TRIP */ 659 static DEVICE_ATTR_RW(power1_average_max); 660 static DEVICE_ATTR_RW(power1_average_min); 661 662 /* depend on POWER_METER_CAN_CAP */ 663 static DEVICE_ATTR_RO(power1_cap_hyst); 664 665 /* depend on POWER_METER_CAN_MEASURE */ 666 static DEVICE_ATTR_RO(power1_accuracy); 667 static DEVICE_ATTR_RO(power1_is_battery); 668 669 static DEVICE_ATTR_RO(power1_model_number); 670 static DEVICE_ATTR_RO(power1_oem_info); 671 static DEVICE_ATTR_RO(power1_serial_number); 672 673 static umode_t power_extra_is_visible(struct kobject *kobj, 674 struct attribute *attr, int idx) 675 { 676 struct device *dev = kobj_to_dev(kobj); 677 struct acpi_power_meter_resource *res = dev_get_drvdata(dev); 678 679 if (attr == &dev_attr_power1_is_battery.attr || 680 attr == &dev_attr_power1_accuracy.attr) { 681 if ((res->caps.flags & POWER_METER_CAN_MEASURE) == 0) 682 return 0; 683 } 684 685 if (attr == &dev_attr_power1_cap_hyst.attr) { 686 if ((res->caps.flags & POWER_METER_CAN_CAP) == 0) { 687 return 0; 688 } else if (!can_cap_in_hardware()) { 689 dev_warn(&res->acpi_dev->dev, 690 "Ignoring unsafe software power cap!\n"); 691 return 0; 692 } 693 } 694 695 if (attr == &dev_attr_power1_average_max.attr || 696 attr == &dev_attr_power1_average_min.attr) { 697 if ((res->caps.flags & POWER_METER_CAN_TRIP) == 0) 698 return 0; 699 } 700 701 return attr->mode; 702 } 703 704 static struct attribute *power_extra_attrs[] = { 705 &dev_attr_power1_average_max.attr, 706 &dev_attr_power1_average_min.attr, 707 &dev_attr_power1_cap_hyst.attr, 708 &dev_attr_power1_accuracy.attr, 709 &dev_attr_power1_is_battery.attr, 710 &dev_attr_power1_model_number.attr, 711 &dev_attr_power1_oem_info.attr, 712 &dev_attr_power1_serial_number.attr, 713 NULL 714 }; 715 716 static const struct attribute_group power_extra_group = { 717 .attrs = power_extra_attrs, 718 .is_visible = power_extra_is_visible, 719 }; 720 721 __ATTRIBUTE_GROUPS(power_extra); 722 723 static void free_capabilities(struct acpi_power_meter_resource *resource) 724 { 725 acpi_string *str; 726 int i; 727 728 str = &resource->model_number; 729 for (i = 0; i < 3; i++, str++) { 730 kfree(*str); 731 *str = NULL; 732 } 733 } 734 735 static int read_capabilities(struct acpi_power_meter_resource *resource) 736 { 737 int res = 0; 738 int i; 739 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 740 struct acpi_buffer state = { 0, NULL }; 741 struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" }; 742 union acpi_object *pss; 743 acpi_string *str; 744 acpi_status status; 745 746 status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMC", NULL, 747 &buffer); 748 if (ACPI_FAILURE(status)) { 749 acpi_evaluation_failure_warn(resource->acpi_dev->handle, "_PMC", 750 status); 751 return -ENODEV; 752 } 753 754 pss = buffer.pointer; 755 if (!pss || 756 pss->type != ACPI_TYPE_PACKAGE || 757 pss->package.count != 14) { 758 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME 759 "Invalid _PMC data\n"); 760 res = -EFAULT; 761 goto end; 762 } 763 764 /* Grab all the integer data at once */ 765 state.length = sizeof(struct acpi_power_meter_capabilities); 766 state.pointer = &resource->caps; 767 768 status = acpi_extract_package(pss, &format, &state); 769 if (ACPI_FAILURE(status)) { 770 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME 771 "_PMC package parsing failed: %s\n", 772 acpi_format_exception(status)); 773 res = -EFAULT; 774 goto end; 775 } 776 777 if (resource->caps.units) { 778 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME 779 "Unknown units %llu.\n", 780 resource->caps.units); 781 res = -EINVAL; 782 goto end; 783 } 784 785 /* Grab the string data */ 786 str = &resource->model_number; 787 788 for (i = 11; i < 14; i++) { 789 union acpi_object *element = &pss->package.elements[i]; 790 791 if (element->type != ACPI_TYPE_STRING) { 792 res = -EINVAL; 793 goto error; 794 } 795 796 *str = kmemdup_nul(element->string.pointer, element->string.length, 797 GFP_KERNEL); 798 if (!*str) { 799 res = -ENOMEM; 800 goto error; 801 } 802 803 str++; 804 } 805 806 dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n"); 807 goto end; 808 error: 809 free_capabilities(resource); 810 end: 811 kfree(buffer.pointer); 812 return res; 813 } 814 815 /* Handle ACPI event notifications */ 816 static void acpi_power_meter_notify(struct acpi_device *device, u32 event) 817 { 818 struct acpi_power_meter_resource *resource; 819 int res; 820 821 if (!device || !acpi_driver_data(device)) 822 return; 823 824 resource = acpi_driver_data(device); 825 826 switch (event) { 827 case METER_NOTIFY_CONFIG: 828 mutex_lock(&resource->lock); 829 free_capabilities(resource); 830 remove_domain_devices(resource); 831 hwmon_device_unregister(resource->hwmon_dev); 832 res = read_capabilities(resource); 833 if (res) 834 dev_err_once(&device->dev, "read capabilities failed.\n"); 835 res = read_domain_devices(resource); 836 if (res && res != -ENODEV) 837 dev_err_once(&device->dev, "read domain devices failed.\n"); 838 resource->hwmon_dev = 839 hwmon_device_register_with_info(&device->dev, 840 ACPI_POWER_METER_NAME, 841 resource, 842 &power_meter_chip_info, 843 power_extra_groups); 844 if (IS_ERR(resource->hwmon_dev)) 845 dev_err_once(&device->dev, "register hwmon device failed.\n"); 846 mutex_unlock(&resource->lock); 847 break; 848 case METER_NOTIFY_TRIP: 849 sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME); 850 break; 851 case METER_NOTIFY_CAP: 852 mutex_lock(&resource->lock); 853 res = update_cap(resource); 854 if (res) 855 dev_err_once(&device->dev, "update cap failed when capping value is changed.\n"); 856 mutex_unlock(&resource->lock); 857 sysfs_notify(&device->dev.kobj, NULL, POWER_CAP_NAME); 858 break; 859 case METER_NOTIFY_INTERVAL: 860 sysfs_notify(&device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME); 861 break; 862 case METER_NOTIFY_CAPPING: 863 mutex_lock(&resource->lock); 864 resource->power_alarm = true; 865 mutex_unlock(&resource->lock); 866 sysfs_notify(&device->dev.kobj, NULL, POWER_ALARM_NAME); 867 dev_info(&device->dev, "Capping in progress.\n"); 868 break; 869 default: 870 WARN(1, "Unexpected event %d\n", event); 871 break; 872 } 873 874 acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS, 875 dev_name(&device->dev), event, 0); 876 } 877 878 static int acpi_power_meter_add(struct acpi_device *device) 879 { 880 int res; 881 struct acpi_power_meter_resource *resource; 882 883 if (!device) 884 return -EINVAL; 885 886 resource = kzalloc(sizeof(*resource), GFP_KERNEL); 887 if (!resource) 888 return -ENOMEM; 889 890 resource->sensors_valid = 0; 891 resource->acpi_dev = device; 892 mutex_init(&resource->lock); 893 strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME); 894 strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS); 895 device->driver_data = resource; 896 897 #if IS_REACHABLE(CONFIG_ACPI_IPMI) 898 /* 899 * On Dell systems several methods of acpi_power_meter access 900 * variables in IPMI region, so wait until IPMI space handler is 901 * installed by acpi_ipmi and also wait until SMI is selected to make 902 * the space handler fully functional. 903 */ 904 if (dmi_match(DMI_SYS_VENDOR, "Dell Inc.")) { 905 struct acpi_device *ipi_device = acpi_dev_get_first_match_dev("IPI0001", NULL, -1); 906 907 if (ipi_device && acpi_wait_for_acpi_ipmi()) 908 dev_warn(&device->dev, "Waiting for ACPI IPMI timeout"); 909 acpi_dev_put(ipi_device); 910 } 911 #endif 912 913 res = read_capabilities(resource); 914 if (res) 915 goto exit_free; 916 917 resource->trip[0] = -1; 918 resource->trip[1] = -1; 919 920 /* _PMD method is optional. */ 921 res = read_domain_devices(resource); 922 if (res && res != -ENODEV) 923 goto exit_free_capability; 924 925 resource->hwmon_dev = 926 hwmon_device_register_with_info(&device->dev, 927 ACPI_POWER_METER_NAME, resource, 928 &power_meter_chip_info, 929 power_extra_groups); 930 if (IS_ERR(resource->hwmon_dev)) { 931 res = PTR_ERR(resource->hwmon_dev); 932 goto exit_remove; 933 } 934 935 res = 0; 936 goto exit; 937 938 exit_remove: 939 remove_domain_devices(resource); 940 exit_free_capability: 941 free_capabilities(resource); 942 exit_free: 943 kfree(resource); 944 exit: 945 return res; 946 } 947 948 static void acpi_power_meter_remove(struct acpi_device *device) 949 { 950 struct acpi_power_meter_resource *resource; 951 952 if (!device || !acpi_driver_data(device)) 953 return; 954 955 resource = acpi_driver_data(device); 956 hwmon_device_unregister(resource->hwmon_dev); 957 958 remove_domain_devices(resource); 959 free_capabilities(resource); 960 961 kfree(resource); 962 } 963 964 static int acpi_power_meter_resume(struct device *dev) 965 { 966 struct acpi_power_meter_resource *resource; 967 968 if (!dev) 969 return -EINVAL; 970 971 resource = acpi_driver_data(to_acpi_device(dev)); 972 if (!resource) 973 return -EINVAL; 974 975 free_capabilities(resource); 976 read_capabilities(resource); 977 978 return 0; 979 } 980 981 static DEFINE_SIMPLE_DEV_PM_OPS(acpi_power_meter_pm, NULL, 982 acpi_power_meter_resume); 983 984 static struct acpi_driver acpi_power_meter_driver = { 985 .name = "power_meter", 986 .class = ACPI_POWER_METER_CLASS, 987 .ids = power_meter_ids, 988 .ops = { 989 .add = acpi_power_meter_add, 990 .remove = acpi_power_meter_remove, 991 .notify = acpi_power_meter_notify, 992 }, 993 .drv.pm = pm_sleep_ptr(&acpi_power_meter_pm), 994 }; 995 996 /* Module init/exit routines */ 997 static int __init enable_cap_knobs(const struct dmi_system_id *d) 998 { 999 cap_in_hardware = 1; 1000 return 0; 1001 } 1002 1003 static const struct dmi_system_id pm_dmi_table[] __initconst = { 1004 { 1005 enable_cap_knobs, "IBM Active Energy Manager", 1006 { 1007 DMI_MATCH(DMI_SYS_VENDOR, "IBM") 1008 }, 1009 }, 1010 {} 1011 }; 1012 1013 static int __init acpi_power_meter_init(void) 1014 { 1015 int result; 1016 1017 if (acpi_disabled) 1018 return -ENODEV; 1019 1020 dmi_check_system(pm_dmi_table); 1021 1022 result = acpi_bus_register_driver(&acpi_power_meter_driver); 1023 if (result < 0) 1024 return result; 1025 1026 return 0; 1027 } 1028 1029 static void __exit acpi_power_meter_exit(void) 1030 { 1031 acpi_bus_unregister_driver(&acpi_power_meter_driver); 1032 } 1033 1034 MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>"); 1035 MODULE_DESCRIPTION("ACPI 4.0 power meter driver"); 1036 MODULE_LICENSE("GPL"); 1037 1038 module_param(force_cap_on, bool, 0644); 1039 MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so."); 1040 1041 module_init(acpi_power_meter_init); 1042 module_exit(acpi_power_meter_exit); 1043