drivers/acpi/power_meter.c

   1 /*
   2  * A hwmon driver for ACPI 4.0 power meters
   3  * Copyright (C) 2009 IBM
   4  *
   5  * Author: Darrick J. Wong <djwong@us.ibm.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/hwmon.h>
  24 #include <linux/hwmon-sysfs.h>
  25 #include <linux/jiffies.h>
  26 #include <linux/mutex.h>
  27 #include <linux/dmi.h>
  28 #include <linux/kdev_t.h>
  29 #include <linux/sched.h>
  30 #include <linux/time.h>
  31 #include <acpi/acpi_drivers.h>
  32 #include <acpi/acpi_bus.h>
  33
  34 #define ACPI_POWER_METER_NAME           "power_meter"
  35 ACPI_MODULE_NAME(ACPI_POWER_METER_NAME);
  36 #define ACPI_POWER_METER_DEVICE_NAME    "Power Meter"
  37 #define ACPI_POWER_METER_CLASS          "power_meter_resource"
  38
  39 #define NUM_SENSORS                     17
  40
  41 #define POWER_METER_CAN_MEASURE (1 << 0)
  42 #define POWER_METER_CAN_TRIP    (1 << 1)
  43 #define POWER_METER_CAN_CAP     (1 << 2)
  44 #define POWER_METER_CAN_NOTIFY  (1 << 3)
  45 #define POWER_METER_IS_BATTERY  (1 << 8)
  46 #define UNKNOWN_HYSTERESIS      0xFFFFFFFF
  47
  48 #define METER_NOTIFY_CONFIG     0x80
  49 #define METER_NOTIFY_TRIP       0x81
  50 #define METER_NOTIFY_CAP        0x82
  51 #define METER_NOTIFY_CAPPING    0x83
  52 #define METER_NOTIFY_INTERVAL   0x84
  53
  54 #define POWER_AVERAGE_NAME      "power1_average"
  55 #define POWER_CAP_NAME          "power1_cap"
  56 #define POWER_AVG_INTERVAL_NAME "power1_average_interval"
  57 #define POWER_ALARM_NAME        "power1_alarm"
  58
  59 static int cap_in_hardware;
  60 static int force_cap_on;
  61
  62 static int can_cap_in_hardware(void)
  63 {
  64         return force_cap_on || cap_in_hardware;
  65 }
  66
  67 static struct acpi_device_id power_meter_ids[] = {
  68         {"ACPI000D", 0},
  69         {"", 0},
  70 };
  71 MODULE_DEVICE_TABLE(acpi, power_meter_ids);
  72
  73 struct acpi_power_meter_capabilities {
  74         acpi_integer            flags;
  75         acpi_integer            units;
  76         acpi_integer            type;
  77         acpi_integer            accuracy;
  78         acpi_integer            sampling_time;
  79         acpi_integer            min_avg_interval;
  80         acpi_integer            max_avg_interval;
  81         acpi_integer            hysteresis;
  82         acpi_integer            configurable_cap;
  83         acpi_integer            min_cap;
  84         acpi_integer            max_cap;
  85 };
  86
  87 struct acpi_power_meter_resource {
  88         struct acpi_device      *acpi_dev;
  89         acpi_bus_id             name;
  90         struct mutex            lock;
  91         struct device           *hwmon_dev;
  92         struct acpi_power_meter_capabilities    caps;
  93         acpi_string             model_number;
  94         acpi_string             serial_number;
  95         acpi_string             oem_info;
  96         acpi_integer            power;
  97         acpi_integer            cap;
  98         acpi_integer            avg_interval;
  99         int                     sensors_valid;
 100         unsigned long           sensors_last_updated;
 101         struct sensor_device_attribute  sensors[NUM_SENSORS];
 102         int                     num_sensors;
 103         int                     trip[2];
 104         int                     num_domain_devices;
 105         struct acpi_device      **domain_devices;
 106         struct kobject          *holders_dir;
 107 };
 108
 109 struct ro_sensor_template {
 110         char *label;
 111         ssize_t (*show)(struct device *dev,
 112                         struct device_attribute *devattr,
 113                         char *buf);
 114         int index;
 115 };
 116
 117 struct rw_sensor_template {
 118         char *label;
 119         ssize_t (*show)(struct device *dev,
 120                         struct device_attribute *devattr,
 121                         char *buf);
 122         ssize_t (*set)(struct device *dev,
 123                        struct device_attribute *devattr,
 124                        const char *buf, size_t count);
 125         int index;
 126 };
 127
 128 /* Averaging interval */
 129 static int update_avg_interval(struct acpi_power_meter_resource *resource)
 130 {
 131         unsigned long long data;
 132         acpi_status status;
 133
 134         status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GAI",
 135                                        NULL, &data);
 136         if (ACPI_FAILURE(status)) {
 137                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _GAI"));
 138                 return -ENODEV;
 139         }
 140
 141         resource->avg_interval = data;
 142         return 0;
 143 }
 144
 145 static ssize_t show_avg_interval(struct device *dev,
 146                                  struct device_attribute *devattr,
 147                                  char *buf)
 148 {
 149         struct acpi_device *acpi_dev = to_acpi_device(dev);
 150         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 151
 152         mutex_lock(&resource->lock);
 153         update_avg_interval(resource);
 154         mutex_unlock(&resource->lock);
 155
 156         return sprintf(buf, "%llu\n", resource->avg_interval);
 157 }
 158
 159 static ssize_t set_avg_interval(struct device *dev,
 160                                 struct device_attribute *devattr,
 161                                 const char *buf, size_t count)
 162 {
 163         struct acpi_device *acpi_dev = to_acpi_device(dev);
 164         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 165         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 166         struct acpi_object_list args = { 1, &arg0 };
 167         int res;
 168         unsigned long temp;
 169         unsigned long long data;
 170         acpi_status status;
 171
 172         res = strict_strtoul(buf, 10, &temp);
 173         if (res)
 174                 return res;
 175
 176         if (temp > resource->caps.max_avg_interval ||
 177             temp < resource->caps.min_avg_interval)
 178                 return -EINVAL;
 179         arg0.integer.value = temp;
 180
 181         mutex_lock(&resource->lock);
 182         status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PAI",
 183                                        &args, &data);
 184         if (!ACPI_FAILURE(status))
 185                 resource->avg_interval = temp;
 186         mutex_unlock(&resource->lock);
 187
 188         if (ACPI_FAILURE(status)) {
 189                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PAI"));
 190                 return -EINVAL;
 191         }
 192
 193         /* _PAI returns 0 on success, nonzero otherwise */
 194         if (data)
 195                 return -EINVAL;
 196
 197         return count;
 198 }
 199
 200 /* Cap functions */
 201 static int update_cap(struct acpi_power_meter_resource *resource)
 202 {
 203         unsigned long long data;
 204         acpi_status status;
 205
 206         status = acpi_evaluate_integer(resource->acpi_dev->handle, "_GHL",
 207                                        NULL, &data);
 208         if (ACPI_FAILURE(status)) {
 209                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _GHL"));
 210                 return -ENODEV;
 211         }
 212
 213         resource->cap = data;
 214         return 0;
 215 }
 216
 217 static ssize_t show_cap(struct device *dev,
 218                         struct device_attribute *devattr,
 219                         char *buf)
 220 {
 221         struct acpi_device *acpi_dev = to_acpi_device(dev);
 222         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 223
 224         mutex_lock(&resource->lock);
 225         update_cap(resource);
 226         mutex_unlock(&resource->lock);
 227
 228         return sprintf(buf, "%llu\n", resource->cap * 1000);
 229 }
 230
 231 static ssize_t set_cap(struct device *dev, struct device_attribute *devattr,
 232                        const char *buf, size_t count)
 233 {
 234         struct acpi_device *acpi_dev = to_acpi_device(dev);
 235         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 236         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 237         struct acpi_object_list args = { 1, &arg0 };
 238         int res;
 239         unsigned long temp;
 240         unsigned long long data;
 241         acpi_status status;
 242
 243         res = strict_strtoul(buf, 10, &temp);
 244         if (res)
 245                 return res;
 246
 247         temp /= 1000;
 248         if (temp > resource->caps.max_cap || temp < resource->caps.min_cap)
 249                 return -EINVAL;
 250         arg0.integer.value = temp;
 251
 252         mutex_lock(&resource->lock);
 253         status = acpi_evaluate_integer(resource->acpi_dev->handle, "_SHL",
 254                                        &args, &data);
 255         if (!ACPI_FAILURE(status))
 256                 resource->cap = temp;
 257         mutex_unlock(&resource->lock);
 258
 259         if (ACPI_FAILURE(status)) {
 260                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SHL"));
 261                 return -EINVAL;
 262         }
 263
 264         /* _SHL returns 0 on success, nonzero otherwise */
 265         if (data)
 266                 return -EINVAL;
 267
 268         return count;
 269 }
 270
 271 /* Power meter trip points */
 272 static int set_acpi_trip(struct acpi_power_meter_resource *resource)
 273 {
 274         union acpi_object arg_objs[] = {
 275                 {ACPI_TYPE_INTEGER},
 276                 {ACPI_TYPE_INTEGER}
 277         };
 278         struct acpi_object_list args = { 2, arg_objs };
 279         unsigned long long data;
 280         acpi_status status;
 281
 282         /* Both trip levels must be set */
 283         if (resource->trip[0] < 0 || resource->trip[1] < 0)
 284                 return 0;
 285
 286         /* This driver stores min, max; ACPI wants max, min. */
 287         arg_objs[0].integer.value = resource->trip[1];
 288         arg_objs[1].integer.value = resource->trip[0];
 289
 290         status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PTP",
 291                                        &args, &data);
 292         if (ACPI_FAILURE(status)) {
 293                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTP"));
 294                 return -EINVAL;
 295         }
 296
 297         /* _PTP returns 0 on success, nonzero otherwise */
 298         if (data)
 299                 return -EINVAL;
 300
 301         return 0;
 302 }
 303
 304 static ssize_t set_trip(struct device *dev, struct device_attribute *devattr,
 305                         const char *buf, size_t count)
 306 {
 307         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 308         struct acpi_device *acpi_dev = to_acpi_device(dev);
 309         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 310         int res;
 311         unsigned long temp;
 312
 313         res = strict_strtoul(buf, 10, &temp);
 314         if (res)
 315                 return res;
 316
 317         temp /= 1000;
 318         if (temp < 0)
 319                 return -EINVAL;
 320
 321         mutex_lock(&resource->lock);
 322         resource->trip[attr->index - 7] = temp;
 323         res = set_acpi_trip(resource);
 324         mutex_unlock(&resource->lock);
 325
 326         if (res)
 327                 return res;
 328
 329         return count;
 330 }
 331
 332 /* Power meter */
 333 static int update_meter(struct acpi_power_meter_resource *resource)
 334 {
 335         unsigned long long data;
 336         acpi_status status;
 337         unsigned long local_jiffies = jiffies;
 338
 339         if (time_before(local_jiffies, resource->sensors_last_updated +
 340                         msecs_to_jiffies(resource->caps.sampling_time)) &&
 341                         resource->sensors_valid)
 342                 return 0;
 343
 344         status = acpi_evaluate_integer(resource->acpi_dev->handle, "_PMM",
 345                                        NULL, &data);
 346         if (ACPI_FAILURE(status)) {
 347                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMM"));
 348                 return -ENODEV;
 349         }
 350
 351         resource->power = data;
 352         resource->sensors_valid = 1;
 353         resource->sensors_last_updated = jiffies;
 354         return 0;
 355 }
 356
 357 static ssize_t show_power(struct device *dev,
 358                           struct device_attribute *devattr,
 359                           char *buf)
 360 {
 361         struct acpi_device *acpi_dev = to_acpi_device(dev);
 362         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 363
 364         mutex_lock(&resource->lock);
 365         update_meter(resource);
 366         mutex_unlock(&resource->lock);
 367
 368         return sprintf(buf, "%llu\n", resource->power * 1000);
 369 }
 370
 371 /* Miscellaneous */
 372 static ssize_t show_str(struct device *dev,
 373                         struct device_attribute *devattr,
 374                         char *buf)
 375 {
 376         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 377         struct acpi_device *acpi_dev = to_acpi_device(dev);
 378         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 379         acpi_string val;
 380
 381         switch (attr->index) {
 382         case 0:
 383                 val = resource->model_number;
 384                 break;
 385         case 1:
 386                 val = resource->serial_number;
 387                 break;
 388         case 2:
 389                 val = resource->oem_info;
 390                 break;
 391         default:
 392                 BUG();
 393         }
 394
 395         return sprintf(buf, "%s\n", val);
 396 }
 397
 398 static ssize_t show_val(struct device *dev,
 399                         struct device_attribute *devattr,
 400                         char *buf)
 401 {
 402         struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
 403         struct acpi_device *acpi_dev = to_acpi_device(dev);
 404         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 405         acpi_integer val = 0;
 406
 407         switch (attr->index) {
 408         case 0:
 409                 val = resource->caps.min_avg_interval;
 410                 break;
 411         case 1:
 412                 val = resource->caps.max_avg_interval;
 413                 break;
 414         case 2:
 415                 val = resource->caps.min_cap * 1000;
 416                 break;
 417         case 3:
 418                 val = resource->caps.max_cap * 1000;
 419                 break;
 420         case 4:
 421                 if (resource->caps.hysteresis == UNKNOWN_HYSTERESIS)
 422                         return sprintf(buf, "unknown\n");
 423
 424                 val = resource->caps.hysteresis * 1000;
 425                 break;
 426         case 5:
 427                 if (resource->caps.flags & POWER_METER_IS_BATTERY)
 428                         val = 1;
 429                 else
 430                         val = 0;
 431                 break;
 432         case 6:
 433                 if (resource->power > resource->cap)
 434                         val = 1;
 435                 else
 436                         val = 0;
 437                 break;
 438         case 7:
 439         case 8:
 440                 if (resource->trip[attr->index - 7] < 0)
 441                         return sprintf(buf, "unknown\n");
 442
 443                 val = resource->trip[attr->index - 7] * 1000;
 444                 break;
 445         default:
 446                 BUG();
 447         }
 448
 449         return sprintf(buf, "%llu\n", val);
 450 }
 451
 452 static ssize_t show_accuracy(struct device *dev,
 453                              struct device_attribute *devattr,
 454                              char *buf)
 455 {
 456         struct acpi_device *acpi_dev = to_acpi_device(dev);
 457         struct acpi_power_meter_resource *resource = acpi_dev->driver_data;
 458         unsigned int acc = resource->caps.accuracy;
 459
 460         return sprintf(buf, "%u.%u%%\n", acc / 1000, acc % 1000);
 461 }
 462
 463 static ssize_t show_name(struct device *dev,
 464                          struct device_attribute *devattr,
 465                          char *buf)
 466 {
 467         return sprintf(buf, "%s\n", ACPI_POWER_METER_NAME);
 468 }
 469
 470 /* Sensor descriptions.  If you add a sensor, update NUM_SENSORS above! */
 471 static struct ro_sensor_template meter_ro_attrs[] = {
 472 {POWER_AVERAGE_NAME, show_power, 0},
 473 {"power1_accuracy", show_accuracy, 0},
 474 {"power1_average_interval_min", show_val, 0},
 475 {"power1_average_interval_max", show_val, 1},
 476 {"power1_is_battery", show_val, 5},
 477 {NULL, NULL, 0},
 478 };
 479
 480 static struct rw_sensor_template meter_rw_attrs[] = {
 481 {POWER_AVG_INTERVAL_NAME, show_avg_interval, set_avg_interval, 0},
 482 {NULL, NULL, NULL, 0},
 483 };
 484
 485 static struct ro_sensor_template misc_cap_attrs[] = {
 486 {"power1_cap_min", show_val, 2},
 487 {"power1_cap_max", show_val, 3},
 488 {"power1_cap_hyst", show_val, 4},
 489 {POWER_ALARM_NAME, show_val, 6},
 490 {NULL, NULL, 0},
 491 };
 492
 493 static struct ro_sensor_template ro_cap_attrs[] = {
 494 {POWER_CAP_NAME, show_cap, 0},
 495 {NULL, NULL, 0},
 496 };
 497
 498 static struct rw_sensor_template rw_cap_attrs[] = {
 499 {POWER_CAP_NAME, show_cap, set_cap, 0},
 500 {NULL, NULL, NULL, 0},
 501 };
 502
 503 static struct rw_sensor_template trip_attrs[] = {
 504 {"power1_average_min", show_val, set_trip, 7},
 505 {"power1_average_max", show_val, set_trip, 8},
 506 {NULL, NULL, NULL, 0},
 507 };
 508
 509 static struct ro_sensor_template misc_attrs[] = {
 510 {"name", show_name, 0},
 511 {"power1_model_number", show_str, 0},
 512 {"power1_oem_info", show_str, 2},
 513 {"power1_serial_number", show_str, 1},
 514 {NULL, NULL, 0},
 515 };
 516
 517 /* Read power domain data */
 518 static void remove_domain_devices(struct acpi_power_meter_resource *resource)
 519 {
 520         int i;
 521
 522         if (!resource->num_domain_devices)
 523                 return;
 524
 525         for (i = 0; i < resource->num_domain_devices; i++) {
 526                 struct acpi_device *obj = resource->domain_devices[i];
 527                 if (!obj)
 528                         continue;
 529
 530                 sysfs_remove_link(resource->holders_dir,
 531                                   kobject_name(&obj->dev.kobj));
 532                 put_device(&obj->dev);
 533         }
 534
 535         kfree(resource->domain_devices);
 536         kobject_put(resource->holders_dir);
 537 }
 538
 539 static int read_domain_devices(struct acpi_power_meter_resource *resource)
 540 {
 541         int res = 0;
 542         int i;
 543         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 544         union acpi_object *pss;
 545         acpi_status status;
 546
 547         status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMD", NULL,
 548                                       &buffer);
 549         if (ACPI_FAILURE(status)) {
 550                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMD"));
 551                 return -ENODEV;
 552         }
 553
 554         pss = buffer.pointer;
 555         if (!pss ||
 556             pss->type != ACPI_TYPE_PACKAGE) {
 557                 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
 558                         "Invalid _PMD data\n");
 559                 res = -EFAULT;
 560                 goto end;
 561         }
 562
 563         if (!pss->package.count)
 564                 goto end;
 565
 566         resource->domain_devices = kzalloc(sizeof(struct acpi_device *) *
 567                                            pss->package.count, GFP_KERNEL);
 568         if (!resource->domain_devices) {
 569                 res = -ENOMEM;
 570                 goto end;
 571         }
 572
 573         resource->holders_dir = kobject_create_and_add("measures",
 574                                         &resource->acpi_dev->dev.kobj);
 575         if (!resource->holders_dir) {
 576                 res = -ENOMEM;
 577                 goto exit_free;
 578         }
 579
 580         resource->num_domain_devices = pss->package.count;
 581
 582         for (i = 0; i < pss->package.count; i++) {
 583                 struct acpi_device *obj;
 584                 union acpi_object *element = &(pss->package.elements[i]);
 585
 586                 /* Refuse non-references */
 587                 if (element->type != ACPI_TYPE_LOCAL_REFERENCE)
 588                         continue;
 589
 590                 /* Create a symlink to domain objects */
 591                 resource->domain_devices[i] = NULL;
 592                 status = acpi_bus_get_device(element->reference.handle,
 593                                              &resource->domain_devices[i]);
 594                 if (ACPI_FAILURE(status))
 595                         continue;
 596
 597                 obj = resource->domain_devices[i];
 598                 get_device(&obj->dev);
 599
 600                 res = sysfs_create_link(resource->holders_dir, &obj->dev.kobj,
 601                                       kobject_name(&obj->dev.kobj));
 602                 if (res) {
 603                         put_device(&obj->dev);
 604                         resource->domain_devices[i] = NULL;
 605                 }
 606         }
 607
 608         res = 0;
 609         goto end;
 610
 611 exit_free:
 612         kfree(resource->domain_devices);
 613 end:
 614         kfree(buffer.pointer);
 615         return res;
 616 }
 617
 618 /* Registration and deregistration */
 619 static int register_ro_attrs(struct acpi_power_meter_resource *resource,
 620                              struct ro_sensor_template *ro)
 621 {
 622         struct device *dev = &resource->acpi_dev->dev;
 623         struct sensor_device_attribute *sensors =
 624                 &resource->sensors[resource->num_sensors];
 625         int res = 0;
 626
 627         while (ro->label) {
 628                 sensors->dev_attr.attr.name = ro->label;
 629                 sensors->dev_attr.attr.mode = S_IRUGO;
 630                 sensors->dev_attr.show = ro->show;
 631                 sensors->index = ro->index;
 632
 633                 res = device_create_file(dev, &sensors->dev_attr);
 634                 if (res) {
 635                         sensors->dev_attr.attr.name = NULL;
 636                         goto error;
 637                 }
 638                 sensors++;
 639                 resource->num_sensors++;
 640                 ro++;
 641         }
 642
 643 error:
 644         return res;
 645 }
 646
 647 static int register_rw_attrs(struct acpi_power_meter_resource *resource,
 648                              struct rw_sensor_template *rw)
 649 {
 650         struct device *dev = &resource->acpi_dev->dev;
 651         struct sensor_device_attribute *sensors =
 652                 &resource->sensors[resource->num_sensors];
 653         int res = 0;
 654
 655         while (rw->label) {
 656                 sensors->dev_attr.attr.name = rw->label;
 657                 sensors->dev_attr.attr.mode = S_IRUGO | S_IWUSR;
 658                 sensors->dev_attr.show = rw->show;
 659                 sensors->dev_attr.store = rw->set;
 660                 sensors->index = rw->index;
 661
 662                 res = device_create_file(dev, &sensors->dev_attr);
 663                 if (res) {
 664                         sensors->dev_attr.attr.name = NULL;
 665                         goto error;
 666                 }
 667                 sensors++;
 668                 resource->num_sensors++;
 669                 rw++;
 670         }
 671
 672 error:
 673         return res;
 674 }
 675
 676 static void remove_attrs(struct acpi_power_meter_resource *resource)
 677 {
 678         int i;
 679
 680         for (i = 0; i < resource->num_sensors; i++) {
 681                 if (!resource->sensors[i].dev_attr.attr.name)
 682                         continue;
 683                 device_remove_file(&resource->acpi_dev->dev,
 684                                    &resource->sensors[i].dev_attr);
 685         }
 686
 687         remove_domain_devices(resource);
 688
 689         resource->num_sensors = 0;
 690 }
 691
 692 static int setup_attrs(struct acpi_power_meter_resource *resource)
 693 {
 694         int res = 0;
 695
 696         res = read_domain_devices(resource);
 697         if (res)
 698                 return res;
 699
 700         if (resource->caps.flags & POWER_METER_CAN_MEASURE) {
 701                 res = register_ro_attrs(resource, meter_ro_attrs);
 702                 if (res)
 703                         goto error;
 704                 res = register_rw_attrs(resource, meter_rw_attrs);
 705                 if (res)
 706                         goto error;
 707         }
 708
 709         if (resource->caps.flags & POWER_METER_CAN_CAP) {
 710                 if (!can_cap_in_hardware()) {
 711                         dev_err(&resource->acpi_dev->dev,
 712                                 "Ignoring unsafe software power cap!\n");
 713                         goto skip_unsafe_cap;
 714                 }
 715
 716                 if (resource->caps.configurable_cap) {
 717                         res = register_rw_attrs(resource, rw_cap_attrs);
 718                         if (res)
 719                                 goto error;
 720                 } else {
 721                         res = register_ro_attrs(resource, ro_cap_attrs);
 722                         if (res)
 723                                 goto error;
 724                 }
 725                 res = register_ro_attrs(resource, misc_cap_attrs);
 726                 if (res)
 727                         goto error;
 728         }
 729 skip_unsafe_cap:
 730
 731         if (resource->caps.flags & POWER_METER_CAN_TRIP) {
 732                 res = register_rw_attrs(resource, trip_attrs);
 733                 if (res)
 734                         goto error;
 735         }
 736
 737         res = register_ro_attrs(resource, misc_attrs);
 738         if (res)
 739                 goto error;
 740
 741         return res;
 742 error:
 743         remove_domain_devices(resource);
 744         remove_attrs(resource);
 745         return res;
 746 }
 747
 748 static void free_capabilities(struct acpi_power_meter_resource *resource)
 749 {
 750         acpi_string *str;
 751         int i;
 752
 753         str = &resource->model_number;
 754         for (i = 0; i < 3; i++, str++)
 755                 kfree(*str);
 756 }
 757
 758 static int read_capabilities(struct acpi_power_meter_resource *resource)
 759 {
 760         int res = 0;
 761         int i;
 762         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 763         struct acpi_buffer state = { 0, NULL };
 764         struct acpi_buffer format = { sizeof("NNNNNNNNNNN"), "NNNNNNNNNNN" };
 765         union acpi_object *pss;
 766         acpi_string *str;
 767         acpi_status status;
 768
 769         status = acpi_evaluate_object(resource->acpi_dev->handle, "_PMC", NULL,
 770                                       &buffer);
 771         if (ACPI_FAILURE(status)) {
 772                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PMC"));
 773                 return -ENODEV;
 774         }
 775
 776         pss = buffer.pointer;
 777         if (!pss ||
 778             pss->type != ACPI_TYPE_PACKAGE ||
 779             pss->package.count != 14) {
 780                 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
 781                         "Invalid _PMC data\n");
 782                 res = -EFAULT;
 783                 goto end;
 784         }
 785
 786         /* Grab all the integer data at once */
 787         state.length = sizeof(struct acpi_power_meter_capabilities);
 788         state.pointer = &resource->caps;
 789
 790         status = acpi_extract_package(pss, &format, &state);
 791         if (ACPI_FAILURE(status)) {
 792                 ACPI_EXCEPTION((AE_INFO, status, "Invalid data"));
 793                 res = -EFAULT;
 794                 goto end;
 795         }
 796
 797         if (resource->caps.units) {
 798                 dev_err(&resource->acpi_dev->dev, ACPI_POWER_METER_NAME
 799                         "Unknown units %llu.\n",
 800                         resource->caps.units);
 801                 res = -EINVAL;
 802                 goto end;
 803         }
 804
 805         /* Grab the string data */
 806         str = &resource->model_number;
 807
 808         for (i = 11; i < 14; i++) {
 809                 union acpi_object *element = &(pss->package.elements[i]);
 810
 811                 if (element->type != ACPI_TYPE_STRING) {
 812                         res = -EINVAL;
 813                         goto error;
 814                 }
 815
 816                 *str = kzalloc(sizeof(u8) * (element->string.length + 1),
 817                                GFP_KERNEL);
 818                 if (!*str) {
 819                         res = -ENOMEM;
 820                         goto error;
 821                 }
 822
 823                 strncpy(*str, element->string.pointer, element->string.length);
 824                 str++;
 825         }
 826
 827         dev_info(&resource->acpi_dev->dev, "Found ACPI power meter.\n");
 828         goto end;
 829 error:
 830         str = &resource->model_number;
 831         for (i = 0; i < 3; i++, str++)
 832                 kfree(*str);
 833 end:
 834         kfree(buffer.pointer);
 835         return res;
 836 }
 837
 838 /* Handle ACPI event notifications */
 839 static void acpi_power_meter_notify(struct acpi_device *device, u32 event)
 840 {
 841         struct acpi_power_meter_resource *resource;
 842         int res;
 843
 844         if (!device || !acpi_driver_data(device))
 845                 return;
 846
 847         resource = acpi_driver_data(device);
 848
 849         mutex_lock(&resource->lock);
 850         switch (event) {
 851         case METER_NOTIFY_CONFIG:
 852                 free_capabilities(resource);
 853                 res = read_capabilities(resource);
 854                 if (res)
 855                         break;
 856
 857                 remove_attrs(resource);
 858                 setup_attrs(resource);
 859                 break;
 860         case METER_NOTIFY_TRIP:
 861                 sysfs_notify(&device->dev.kobj, NULL, POWER_AVERAGE_NAME);
 862                 update_meter(resource);
 863                 break;
 864         case METER_NOTIFY_CAP:
 865                 sysfs_notify(&device->dev.kobj, NULL, POWER_CAP_NAME);
 866                 update_cap(resource);
 867                 break;
 868         case METER_NOTIFY_INTERVAL:
 869                 sysfs_notify(&device->dev.kobj, NULL, POWER_AVG_INTERVAL_NAME);
 870                 update_avg_interval(resource);
 871                 break;
 872         case METER_NOTIFY_CAPPING:
 873                 sysfs_notify(&device->dev.kobj, NULL, POWER_ALARM_NAME);
 874                 dev_info(&device->dev, "Capping in progress.\n");
 875                 break;
 876         default:
 877                 BUG();
 878         }
 879         mutex_unlock(&resource->lock);
 880
 881         acpi_bus_generate_netlink_event(ACPI_POWER_METER_CLASS,
 882                                         dev_name(&device->dev), event, 0);
 883 }
 884
 885 static int acpi_power_meter_add(struct acpi_device *device)
 886 {
 887         int res;
 888         struct acpi_power_meter_resource *resource;
 889
 890         if (!device)
 891                 return -EINVAL;
 892
 893         resource = kzalloc(sizeof(struct acpi_power_meter_resource),
 894                            GFP_KERNEL);
 895         if (!resource)
 896                 return -ENOMEM;
 897
 898         resource->sensors_valid = 0;
 899         resource->acpi_dev = device;
 900         mutex_init(&resource->lock);
 901         strcpy(acpi_device_name(device), ACPI_POWER_METER_DEVICE_NAME);
 902         strcpy(acpi_device_class(device), ACPI_POWER_METER_CLASS);
 903         device->driver_data = resource;
 904
 905         free_capabilities(resource);
 906         res = read_capabilities(resource);
 907         if (res)
 908                 goto exit_free;
 909
 910         resource->trip[0] = resource->trip[1] = -1;
 911
 912         res = setup_attrs(resource);
 913         if (res)
 914                 goto exit_free;
 915
 916         resource->hwmon_dev = hwmon_device_register(&device->dev);
 917         if (IS_ERR(resource->hwmon_dev)) {
 918                 res = PTR_ERR(resource->hwmon_dev);
 919                 goto exit_remove;
 920         }
 921
 922         res = 0;
 923         goto exit;
 924
 925 exit_remove:
 926         remove_attrs(resource);
 927 exit_free:
 928         kfree(resource);
 929 exit:
 930         return res;
 931 }
 932
 933 static int acpi_power_meter_remove(struct acpi_device *device, int type)
 934 {
 935         struct acpi_power_meter_resource *resource;
 936
 937         if (!device || !acpi_driver_data(device))
 938                 return -EINVAL;
 939
 940         resource = acpi_driver_data(device);
 941         hwmon_device_unregister(resource->hwmon_dev);
 942
 943         free_capabilities(resource);
 944         remove_attrs(resource);
 945
 946         kfree(resource);
 947         return 0;
 948 }
 949
 950 static int acpi_power_meter_resume(struct acpi_device *device)
 951 {
 952         struct acpi_power_meter_resource *resource;
 953
 954         if (!device || !acpi_driver_data(device))
 955                 return -EINVAL;
 956
 957         resource = acpi_driver_data(device);
 958         free_capabilities(resource);
 959         read_capabilities(resource);
 960
 961         return 0;
 962 }
 963
 964 static struct acpi_driver acpi_power_meter_driver = {
 965         .name = "power_meter",
 966         .class = ACPI_POWER_METER_CLASS,
 967         .ids = power_meter_ids,
 968         .ops = {
 969                 .add = acpi_power_meter_add,
 970                 .remove = acpi_power_meter_remove,
 971                 .resume = acpi_power_meter_resume,
 972                 .notify = acpi_power_meter_notify,
 973                 },
 974 };
 975
 976 /* Module init/exit routines */
 977 static int __init enable_cap_knobs(const struct dmi_system_id *d)
 978 {
 979         cap_in_hardware = 1;
 980         return 0;
 981 }
 982
 983 static struct dmi_system_id __initdata pm_dmi_table[] = {
 984         {
 985                 enable_cap_knobs, "IBM Active Energy Manager",
 986                 {
 987                         DMI_MATCH(DMI_SYS_VENDOR, "IBM")
 988                 },
 989         },
 990         {}
 991 };
 992
 993 static int __init acpi_power_meter_init(void)
 994 {
 995         int result;
 996
 997         if (acpi_disabled)
 998                 return -ENODEV;
 999
1000         dmi_check_system(pm_dmi_table);
1001
1002         result = acpi_bus_register_driver(&acpi_power_meter_driver);
1003         if (result < 0)
1004                 return -ENODEV;
1005
1006         return 0;
1007 }
1008
1009 static void __exit acpi_power_meter_exit(void)
1010 {
1011         acpi_bus_unregister_driver(&acpi_power_meter_driver);
1012 }
1013
1014 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
1015 MODULE_DESCRIPTION("ACPI 4.0 power meter driver");
1016 MODULE_LICENSE("GPL");
1017
1018 module_param(force_cap_on, bool, 0644);
1019 MODULE_PARM_DESC(force_cap_on, "Enable power cap even it is unsafe to do so.");
1020
1021 module_init(acpi_power_meter_init);
1022 module_exit(acpi_power_meter_exit);