drivers/hwmon/hwmon.c

   1 /*
   2  * hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
   3  *
   4  * This file defines the sysfs class "hwmon", for use by sensors drivers.
   5  *
   6  * Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; version 2 of the License.
  11  */
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/bitops.h>
  16 #include <linux/device.h>
  17 #include <linux/err.h>
  18 #include <linux/gfp.h>
  19 #include <linux/hwmon.h>
  20 #include <linux/idr.h>
  21 #include <linux/module.h>
  22 #include <linux/pci.h>
  23 #include <linux/slab.h>
  24 #include <linux/string.h>
  25 #include <linux/thermal.h>
  26
  27 #define HWMON_ID_PREFIX "hwmon"
  28 #define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
  29
  30 struct hwmon_device {
  31         const char *name;
  32         struct device dev;
  33         const struct hwmon_chip_info *chip;
  34
  35         struct attribute_group group;
  36         const struct attribute_group **groups;
  37 };
  38
  39 #define to_hwmon_device(d) container_of(d, struct hwmon_device, dev)
  40
  41 struct hwmon_device_attribute {
  42         struct device_attribute dev_attr;
  43         const struct hwmon_ops *ops;
  44         enum hwmon_sensor_types type;
  45         u32 attr;
  46         int index;
  47 };
  48
  49 #define to_hwmon_attr(d) \
  50         container_of(d, struct hwmon_device_attribute, dev_attr)
  51
  52 /*
  53  * Thermal zone information
  54  * In addition to the reference to the hwmon device,
  55  * also provides the sensor index.
  56  */
  57 struct hwmon_thermal_data {
  58         struct hwmon_device *hwdev;     /* Reference to hwmon device */
  59         int index;                      /* sensor index */
  60 };
  61
  62 static ssize_t
  63 show_name(struct device *dev, struct device_attribute *attr, char *buf)
  64 {
  65         return sprintf(buf, "%s\n", to_hwmon_device(dev)->name);
  66 }
  67 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
  68
  69 static struct attribute *hwmon_dev_attrs[] = {
  70         &dev_attr_name.attr,
  71         NULL
  72 };
  73
  74 static umode_t hwmon_dev_name_is_visible(struct kobject *kobj,
  75                                          struct attribute *attr, int n)
  76 {
  77         struct device *dev = container_of(kobj, struct device, kobj);
  78
  79         if (to_hwmon_device(dev)->name == NULL)
  80                 return 0;
  81
  82         return attr->mode;
  83 }
  84
  85 static struct attribute_group hwmon_dev_attr_group = {
  86         .attrs          = hwmon_dev_attrs,
  87         .is_visible     = hwmon_dev_name_is_visible,
  88 };
  89
  90 static const struct attribute_group *hwmon_dev_attr_groups[] = {
  91         &hwmon_dev_attr_group,
  92         NULL
  93 };
  94
  95 static void hwmon_dev_release(struct device *dev)
  96 {
  97         kfree(to_hwmon_device(dev));
  98 }
  99
 100 static struct class hwmon_class = {
 101         .name = "hwmon",
 102         .owner = THIS_MODULE,
 103         .dev_groups = hwmon_dev_attr_groups,
 104         .dev_release = hwmon_dev_release,
 105 };
 106
 107 static DEFINE_IDA(hwmon_ida);
 108
 109 /* Thermal zone handling */
 110
 111 /*
 112  * The complex conditional is necessary to avoid a cyclic dependency
 113  * between hwmon and thermal_sys modules.
 114  */
 115 #if IS_REACHABLE(CONFIG_THERMAL) && defined(CONFIG_THERMAL_OF) && \
 116         (!defined(CONFIG_THERMAL_HWMON) || \
 117          !(defined(MODULE) && IS_MODULE(CONFIG_THERMAL)))
 118 static int hwmon_thermal_get_temp(void *data, int *temp)
 119 {
 120         struct hwmon_thermal_data *tdata = data;
 121         struct hwmon_device *hwdev = tdata->hwdev;
 122         int ret;
 123         long t;
 124
 125         ret = hwdev->chip->ops->read(&hwdev->dev, hwmon_temp, hwmon_temp_input,
 126                                      tdata->index, &t);
 127         if (ret < 0)
 128                 return ret;
 129
 130         *temp = t;
 131
 132         return 0;
 133 }
 134
 135 static struct thermal_zone_of_device_ops hwmon_thermal_ops = {
 136         .get_temp = hwmon_thermal_get_temp,
 137 };
 138
 139 static int hwmon_thermal_add_sensor(struct device *dev,
 140                                     struct hwmon_device *hwdev, int index)
 141 {
 142         struct hwmon_thermal_data *tdata;
 143
 144         tdata = devm_kzalloc(dev, sizeof(*tdata), GFP_KERNEL);
 145         if (!tdata)
 146                 return -ENOMEM;
 147
 148         tdata->hwdev = hwdev;
 149         tdata->index = index;
 150
 151         devm_thermal_zone_of_sensor_register(&hwdev->dev, index, tdata,
 152                                              &hwmon_thermal_ops);
 153
 154         return 0;
 155 }
 156 #else
 157 static int hwmon_thermal_add_sensor(struct device *dev,
 158                                     struct hwmon_device *hwdev, int index)
 159 {
 160         return 0;
 161 }
 162 #endif /* IS_REACHABLE(CONFIG_THERMAL) && ... */
 163
 164 /* sysfs attribute management */
 165
 166 static ssize_t hwmon_attr_show(struct device *dev,
 167                                struct device_attribute *devattr, char *buf)
 168 {
 169         struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
 170         long val;
 171         int ret;
 172
 173         ret = hattr->ops->read(dev, hattr->type, hattr->attr, hattr->index,
 174                                &val);
 175         if (ret < 0)
 176                 return ret;
 177
 178         return sprintf(buf, "%ld\n", val);
 179 }
 180
 181 static ssize_t hwmon_attr_store(struct device *dev,
 182                                 struct device_attribute *devattr,
 183                                 const char *buf, size_t count)
 184 {
 185         struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
 186         long val;
 187         int ret;
 188
 189         ret = kstrtol(buf, 10, &val);
 190         if (ret < 0)
 191                 return ret;
 192
 193         ret = hattr->ops->write(dev, hattr->type, hattr->attr, hattr->index,
 194                                 val);
 195         if (ret < 0)
 196                 return ret;
 197
 198         return count;
 199 }
 200
 201 static int hwmon_attr_base(enum hwmon_sensor_types type)
 202 {
 203         if (type == hwmon_in)
 204                 return 0;
 205         return 1;
 206 }
 207
 208 static struct attribute *hwmon_genattr(struct device *dev,
 209                                        const void *drvdata,
 210                                        enum hwmon_sensor_types type,
 211                                        u32 attr,
 212                                        int index,
 213                                        const char *template,
 214                                        const struct hwmon_ops *ops)
 215 {
 216         struct hwmon_device_attribute *hattr;
 217         struct device_attribute *dattr;
 218         struct attribute *a;
 219         umode_t mode;
 220         char *name;
 221
 222         /* The attribute is invisible if there is no template string */
 223         if (!template)
 224                 return ERR_PTR(-ENOENT);
 225
 226         mode = ops->is_visible(drvdata, type, attr, index);
 227         if (!mode)
 228                 return ERR_PTR(-ENOENT);
 229
 230         if ((mode & S_IRUGO) && !ops->read)
 231                 return ERR_PTR(-EINVAL);
 232         if ((mode & S_IWUGO) && !ops->write)
 233                 return ERR_PTR(-EINVAL);
 234
 235         if (type == hwmon_chip) {
 236                 name = (char *)template;
 237         } else {
 238                 name = devm_kzalloc(dev, strlen(template) + 16, GFP_KERNEL);
 239                 if (!name)
 240                         return ERR_PTR(-ENOMEM);
 241                 scnprintf(name, strlen(template) + 16, template,
 242                           index + hwmon_attr_base(type));
 243         }
 244
 245         hattr = devm_kzalloc(dev, sizeof(*hattr), GFP_KERNEL);
 246         if (!hattr)
 247                 return ERR_PTR(-ENOMEM);
 248
 249         hattr->type = type;
 250         hattr->attr = attr;
 251         hattr->index = index;
 252         hattr->ops = ops;
 253
 254         dattr = &hattr->dev_attr;
 255         dattr->show = hwmon_attr_show;
 256         dattr->store = hwmon_attr_store;
 257
 258         a = &dattr->attr;
 259         sysfs_attr_init(a);
 260         a->name = name;
 261         a->mode = mode;
 262
 263         return a;
 264 }
 265
 266 static const char * const hwmon_chip_attr_templates[] = {
 267         [hwmon_chip_temp_reset_history] = "temp_reset_history",
 268         [hwmon_chip_in_reset_history] = "in_reset_history",
 269         [hwmon_chip_curr_reset_history] = "curr_reset_history",
 270         [hwmon_chip_power_reset_history] = "power_reset_history",
 271         [hwmon_chip_update_interval] = "update_interval",
 272         [hwmon_chip_alarms] = "alarms",
 273 };
 274
 275 static const char * const hwmon_temp_attr_templates[] = {
 276         [hwmon_temp_input] = "temp%d_input",
 277         [hwmon_temp_type] = "temp%d_type",
 278         [hwmon_temp_lcrit] = "temp%d_lcrit",
 279         [hwmon_temp_lcrit_hyst] = "temp%d_lcrit_hyst",
 280         [hwmon_temp_min] = "temp%d_min",
 281         [hwmon_temp_min_hyst] = "temp%d_min_hyst",
 282         [hwmon_temp_max] = "temp%d_max",
 283         [hwmon_temp_max_hyst] = "temp%d_max_hyst",
 284         [hwmon_temp_crit] = "temp%d_crit",
 285         [hwmon_temp_crit_hyst] = "temp%d_crit_hyst",
 286         [hwmon_temp_emergency] = "temp%d_emergency",
 287         [hwmon_temp_emergency_hyst] = "temp%d_emergency_hyst",
 288         [hwmon_temp_alarm] = "temp%d_alarm",
 289         [hwmon_temp_lcrit_alarm] = "temp%d_lcrit_alarm",
 290         [hwmon_temp_min_alarm] = "temp%d_min_alarm",
 291         [hwmon_temp_max_alarm] = "temp%d_max_alarm",
 292         [hwmon_temp_crit_alarm] = "temp%d_crit_alarm",
 293         [hwmon_temp_emergency_alarm] = "temp%d_emergency_alarm",
 294         [hwmon_temp_fault] = "temp%d_fault",
 295         [hwmon_temp_offset] = "temp%d_offset",
 296         [hwmon_temp_label] = "temp%d_label",
 297         [hwmon_temp_lowest] = "temp%d_lowest",
 298         [hwmon_temp_highest] = "temp%d_highest",
 299         [hwmon_temp_reset_history] = "temp%d_reset_history",
 300 };
 301
 302 static const char * const hwmon_in_attr_templates[] = {
 303         [hwmon_in_input] = "in%d_input",
 304         [hwmon_in_min] = "in%d_min",
 305         [hwmon_in_max] = "in%d_max",
 306         [hwmon_in_lcrit] = "in%d_lcrit",
 307         [hwmon_in_crit] = "in%d_crit",
 308         [hwmon_in_average] = "in%d_average",
 309         [hwmon_in_lowest] = "in%d_lowest",
 310         [hwmon_in_highest] = "in%d_highest",
 311         [hwmon_in_reset_history] = "in%d_reset_history",
 312         [hwmon_in_label] = "in%d_label",
 313         [hwmon_in_alarm] = "in%d_alarm",
 314         [hwmon_in_min_alarm] = "in%d_min_alarm",
 315         [hwmon_in_max_alarm] = "in%d_max_alarm",
 316         [hwmon_in_lcrit_alarm] = "in%d_lcrit_alarm",
 317         [hwmon_in_crit_alarm] = "in%d_crit_alarm",
 318 };
 319
 320 static const char * const hwmon_curr_attr_templates[] = {
 321         [hwmon_curr_input] = "curr%d_input",
 322         [hwmon_curr_min] = "curr%d_min",
 323         [hwmon_curr_max] = "curr%d_max",
 324         [hwmon_curr_lcrit] = "curr%d_lcrit",
 325         [hwmon_curr_crit] = "curr%d_crit",
 326         [hwmon_curr_average] = "curr%d_average",
 327         [hwmon_curr_lowest] = "curr%d_lowest",
 328         [hwmon_curr_highest] = "curr%d_highest",
 329         [hwmon_curr_reset_history] = "curr%d_reset_history",
 330         [hwmon_curr_label] = "curr%d_label",
 331         [hwmon_curr_alarm] = "curr%d_alarm",
 332         [hwmon_curr_min_alarm] = "curr%d_min_alarm",
 333         [hwmon_curr_max_alarm] = "curr%d_max_alarm",
 334         [hwmon_curr_lcrit_alarm] = "curr%d_lcrit_alarm",
 335         [hwmon_curr_crit_alarm] = "curr%d_crit_alarm",
 336 };
 337
 338 static const char * const hwmon_power_attr_templates[] = {
 339         [hwmon_power_average] = "power%d_average",
 340         [hwmon_power_average_interval] = "power%d_average_interval",
 341         [hwmon_power_average_interval_max] = "power%d_interval_max",
 342         [hwmon_power_average_interval_min] = "power%d_interval_min",
 343         [hwmon_power_average_highest] = "power%d_average_highest",
 344         [hwmon_power_average_lowest] = "power%d_average_lowest",
 345         [hwmon_power_average_max] = "power%d_average_max",
 346         [hwmon_power_average_min] = "power%d_average_min",
 347         [hwmon_power_input] = "power%d_input",
 348         [hwmon_power_input_highest] = "power%d_input_highest",
 349         [hwmon_power_input_lowest] = "power%d_input_lowest",
 350         [hwmon_power_reset_history] = "power%d_reset_history",
 351         [hwmon_power_accuracy] = "power%d_accuracy",
 352         [hwmon_power_cap] = "power%d_cap",
 353         [hwmon_power_cap_hyst] = "power%d_cap_hyst",
 354         [hwmon_power_cap_max] = "power%d_cap_max",
 355         [hwmon_power_cap_min] = "power%d_cap_min",
 356         [hwmon_power_max] = "power%d_max",
 357         [hwmon_power_crit] = "power%d_crit",
 358         [hwmon_power_label] = "power%d_label",
 359         [hwmon_power_alarm] = "power%d_alarm",
 360         [hwmon_power_cap_alarm] = "power%d_cap_alarm",
 361         [hwmon_power_max_alarm] = "power%d_max_alarm",
 362         [hwmon_power_crit_alarm] = "power%d_crit_alarm",
 363 };
 364
 365 static const char * const hwmon_energy_attr_templates[] = {
 366         [hwmon_energy_input] = "energy%d_input",
 367         [hwmon_energy_label] = "energy%d_label",
 368 };
 369
 370 static const char * const hwmon_humidity_attr_templates[] = {
 371         [hwmon_humidity_input] = "humidity%d_input",
 372         [hwmon_humidity_label] = "humidity%d_label",
 373         [hwmon_humidity_min] = "humidity%d_min",
 374         [hwmon_humidity_min_hyst] = "humidity%d_min_hyst",
 375         [hwmon_humidity_max] = "humidity%d_max",
 376         [hwmon_humidity_max_hyst] = "humidity%d_max_hyst",
 377         [hwmon_humidity_alarm] = "humidity%d_alarm",
 378         [hwmon_humidity_fault] = "humidity%d_fault",
 379 };
 380
 381 static const char * const hwmon_fan_attr_templates[] = {
 382         [hwmon_fan_input] = "fan%d_input",
 383         [hwmon_fan_label] = "fan%d_label",
 384         [hwmon_fan_min] = "fan%d_min",
 385         [hwmon_fan_max] = "fan%d_max",
 386         [hwmon_fan_div] = "fan%d_div",
 387         [hwmon_fan_pulses] = "fan%d_pulses",
 388         [hwmon_fan_target] = "fan%d_target",
 389         [hwmon_fan_alarm] = "fan%d_alarm",
 390         [hwmon_fan_min_alarm] = "fan%d_min_alarm",
 391         [hwmon_fan_max_alarm] = "fan%d_max_alarm",
 392         [hwmon_fan_fault] = "fan%d_fault",
 393 };
 394
 395 static const char * const hwmon_pwm_attr_templates[] = {
 396         [hwmon_pwm_input] = "pwm%d",
 397         [hwmon_pwm_enable] = "pwm%d_enable",
 398         [hwmon_pwm_mode] = "pwm%d_mode",
 399         [hwmon_pwm_freq] = "pwm%d_freq",
 400 };
 401
 402 static const char * const *__templates[] = {
 403         [hwmon_chip] = hwmon_chip_attr_templates,
 404         [hwmon_temp] = hwmon_temp_attr_templates,
 405         [hwmon_in] = hwmon_in_attr_templates,
 406         [hwmon_curr] = hwmon_curr_attr_templates,
 407         [hwmon_power] = hwmon_power_attr_templates,
 408         [hwmon_energy] = hwmon_energy_attr_templates,
 409         [hwmon_humidity] = hwmon_humidity_attr_templates,
 410         [hwmon_fan] = hwmon_fan_attr_templates,
 411         [hwmon_pwm] = hwmon_pwm_attr_templates,
 412 };
 413
 414 static const int __templates_size[] = {
 415         [hwmon_chip] = ARRAY_SIZE(hwmon_chip_attr_templates),
 416         [hwmon_temp] = ARRAY_SIZE(hwmon_temp_attr_templates),
 417         [hwmon_in] = ARRAY_SIZE(hwmon_in_attr_templates),
 418         [hwmon_curr] = ARRAY_SIZE(hwmon_curr_attr_templates),
 419         [hwmon_power] = ARRAY_SIZE(hwmon_power_attr_templates),
 420         [hwmon_energy] = ARRAY_SIZE(hwmon_energy_attr_templates),
 421         [hwmon_humidity] = ARRAY_SIZE(hwmon_humidity_attr_templates),
 422         [hwmon_fan] = ARRAY_SIZE(hwmon_fan_attr_templates),
 423         [hwmon_pwm] = ARRAY_SIZE(hwmon_pwm_attr_templates),
 424 };
 425
 426 static int hwmon_num_channel_attrs(const struct hwmon_channel_info *info)
 427 {
 428         int i, n;
 429
 430         for (i = n = 0; info->config[i]; i++)
 431                 n += hweight32(info->config[i]);
 432
 433         return n;
 434 }
 435
 436 static int hwmon_genattrs(struct device *dev,
 437                           const void *drvdata,
 438                           struct attribute **attrs,
 439                           const struct hwmon_ops *ops,
 440                           const struct hwmon_channel_info *info)
 441 {
 442         const char * const *templates;
 443         int template_size;
 444         int i, aindex = 0;
 445
 446         if (info->type >= ARRAY_SIZE(__templates))
 447                 return -EINVAL;
 448
 449         templates = __templates[info->type];
 450         template_size = __templates_size[info->type];
 451
 452         for (i = 0; info->config[i]; i++) {
 453                 u32 attr_mask = info->config[i];
 454                 u32 attr;
 455
 456                 while (attr_mask) {
 457                         struct attribute *a;
 458
 459                         attr = __ffs(attr_mask);
 460                         attr_mask &= ~BIT(attr);
 461                         if (attr >= template_size)
 462                                 return -EINVAL;
 463                         a = hwmon_genattr(dev, drvdata, info->type, attr, i,
 464                                           templates[attr], ops);
 465                         if (IS_ERR(a)) {
 466                                 if (PTR_ERR(a) != -ENOENT)
 467                                         return PTR_ERR(a);
 468                                 continue;
 469                         }
 470                         attrs[aindex++] = a;
 471                 }
 472         }
 473         return aindex;
 474 }
 475
 476 static struct attribute **
 477 __hwmon_create_attrs(struct device *dev, const void *drvdata,
 478                      const struct hwmon_chip_info *chip)
 479 {
 480         int ret, i, aindex = 0, nattrs = 0;
 481         struct attribute **attrs;
 482
 483         for (i = 0; chip->info[i]; i++)
 484                 nattrs += hwmon_num_channel_attrs(chip->info[i]);
 485
 486         if (nattrs == 0)
 487                 return ERR_PTR(-EINVAL);
 488
 489         attrs = devm_kcalloc(dev, nattrs + 1, sizeof(*attrs), GFP_KERNEL);
 490         if (!attrs)
 491                 return ERR_PTR(-ENOMEM);
 492
 493         for (i = 0; chip->info[i]; i++) {
 494                 ret = hwmon_genattrs(dev, drvdata, &attrs[aindex], chip->ops,
 495                                      chip->info[i]);
 496                 if (ret < 0)
 497                         return ERR_PTR(ret);
 498                 aindex += ret;
 499         }
 500
 501         return attrs;
 502 }
 503
 504 static struct device *
 505 __hwmon_device_register(struct device *dev, const char *name, void *drvdata,
 506                         const struct hwmon_chip_info *chip,
 507                         const struct attribute_group **groups)
 508 {
 509         struct hwmon_device *hwdev;
 510         struct device *hdev;
 511         int i, j, err, id;
 512
 513         /* Do not accept invalid characters in hwmon name attribute */
 514         if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
 515                 return ERR_PTR(-EINVAL);
 516
 517         id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
 518         if (id < 0)
 519                 return ERR_PTR(id);
 520
 521         hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
 522         if (hwdev == NULL) {
 523                 err = -ENOMEM;
 524                 goto ida_remove;
 525         }
 526
 527         hdev = &hwdev->dev;
 528
 529         if (chip && chip->ops->is_visible) {
 530                 struct attribute **attrs;
 531                 int ngroups = 2;
 532
 533                 if (groups)
 534                         for (i = 0; groups[i]; i++)
 535                                 ngroups++;
 536
 537                 hwdev->groups = devm_kcalloc(dev, ngroups, sizeof(*groups),
 538                                              GFP_KERNEL);
 539                 if (!hwdev->groups) {
 540                         err = -ENOMEM;
 541                         goto free_hwmon;
 542                 }
 543
 544                 attrs = __hwmon_create_attrs(dev, drvdata, chip);
 545                 if (IS_ERR(attrs)) {
 546                         err = PTR_ERR(attrs);
 547                         goto free_hwmon;
 548                 }
 549
 550                 hwdev->group.attrs = attrs;
 551                 ngroups = 0;
 552                 hwdev->groups[ngroups++] = &hwdev->group;
 553
 554                 if (groups) {
 555                         for (i = 0; groups[i]; i++)
 556                                 hwdev->groups[ngroups++] = groups[i];
 557                 }
 558
 559                 hdev->groups = hwdev->groups;
 560         } else {
 561                 hdev->groups = groups;
 562         }
 563
 564         hwdev->name = name;
 565         hdev->class = &hwmon_class;
 566         hdev->parent = dev;
 567         hdev->of_node = dev ? dev->of_node : NULL;
 568         hwdev->chip = chip;
 569         dev_set_drvdata(hdev, drvdata);
 570         dev_set_name(hdev, HWMON_ID_FORMAT, id);
 571         err = device_register(hdev);
 572         if (err)
 573                 goto free_hwmon;
 574
 575         if (chip && chip->ops->is_visible && chip->ops->read &&
 576             chip->info[0]->type == hwmon_chip &&
 577             (chip->info[0]->config[0] & HWMON_C_REGISTER_TZ)) {
 578                 const struct hwmon_channel_info **info = chip->info;
 579
 580                 for (i = 1; info[i]; i++) {
 581                         if (info[i]->type != hwmon_temp)
 582                                 continue;
 583
 584                         for (j = 0; info[i]->config[j]; j++) {
 585                                 if (!chip->ops->is_visible(drvdata, hwmon_temp,
 586                                                            hwmon_temp_input, j))
 587                                         continue;
 588                                 if (info[i]->config[j] & HWMON_T_INPUT)
 589                                         hwmon_thermal_add_sensor(dev, hwdev, j);
 590                         }
 591                 }
 592         }
 593
 594         return hdev;
 595
 596 free_hwmon:
 597         kfree(hwdev);
 598 ida_remove:
 599         ida_simple_remove(&hwmon_ida, id);
 600         return ERR_PTR(err);
 601 }
 602
 603 /**
 604  * hwmon_device_register_with_groups - register w/ hwmon
 605  * @dev: the parent device
 606  * @name: hwmon name attribute
 607  * @drvdata: driver data to attach to created device
 608  * @groups: List of attribute groups to create
 609  *
 610  * hwmon_device_unregister() must be called when the device is no
 611  * longer needed.
 612  *
 613  * Returns the pointer to the new device.
 614  */
 615 struct device *
 616 hwmon_device_register_with_groups(struct device *dev, const char *name,
 617                                   void *drvdata,
 618                                   const struct attribute_group **groups)
 619 {
 620         return __hwmon_device_register(dev, name, drvdata, NULL, groups);
 621 }
 622 EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);
 623
 624 /**
 625  * hwmon_device_register_with_info - register w/ hwmon
 626  * @dev: the parent device
 627  * @name: hwmon name attribute
 628  * @drvdata: driver data to attach to created device
 629  * @info: Pointer to hwmon chip information
 630  * @groups - pointer to list of driver specific attribute groups
 631  *
 632  * hwmon_device_unregister() must be called when the device is no
 633  * longer needed.
 634  *
 635  * Returns the pointer to the new device.
 636  */
 637 struct device *
 638 hwmon_device_register_with_info(struct device *dev, const char *name,
 639                                 void *drvdata,
 640                                 const struct hwmon_chip_info *chip,
 641                                 const struct attribute_group **groups)
 642 {
 643         if (chip && (!chip->ops || !chip->info))
 644                 return ERR_PTR(-EINVAL);
 645
 646         return __hwmon_device_register(dev, name, drvdata, chip, groups);
 647 }
 648 EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);
 649
 650 /**
 651  * hwmon_device_register - register w/ hwmon
 652  * @dev: the device to register
 653  *
 654  * hwmon_device_unregister() must be called when the device is no
 655  * longer needed.
 656  *
 657  * Returns the pointer to the new device.
 658  */
 659 struct device *hwmon_device_register(struct device *dev)
 660 {
 661         return hwmon_device_register_with_groups(dev, NULL, NULL, NULL);
 662 }
 663 EXPORT_SYMBOL_GPL(hwmon_device_register);
 664
 665 /**
 666  * hwmon_device_unregister - removes the previously registered class device
 667  *
 668  * @dev: the class device to destroy
 669  */
 670 void hwmon_device_unregister(struct device *dev)
 671 {
 672         int id;
 673
 674         if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
 675                 device_unregister(dev);
 676                 ida_simple_remove(&hwmon_ida, id);
 677         } else
 678                 dev_dbg(dev->parent,
 679                         "hwmon_device_unregister() failed: bad class ID!\n");
 680 }
 681 EXPORT_SYMBOL_GPL(hwmon_device_unregister);
 682
 683 static void devm_hwmon_release(struct device *dev, void *res)
 684 {
 685         struct device *hwdev = *(struct device **)res;
 686
 687         hwmon_device_unregister(hwdev);
 688 }
 689
 690 /**
 691  * devm_hwmon_device_register_with_groups - register w/ hwmon
 692  * @dev: the parent device
 693  * @name: hwmon name attribute
 694  * @drvdata: driver data to attach to created device
 695  * @groups: List of attribute groups to create
 696  *
 697  * Returns the pointer to the new device. The new device is automatically
 698  * unregistered with the parent device.
 699  */
 700 struct device *
 701 devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
 702                                        void *drvdata,
 703                                        const struct attribute_group **groups)
 704 {
 705         struct device **ptr, *hwdev;
 706
 707         if (!dev)
 708                 return ERR_PTR(-EINVAL);
 709
 710         ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
 711         if (!ptr)
 712                 return ERR_PTR(-ENOMEM);
 713
 714         hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
 715         if (IS_ERR(hwdev))
 716                 goto error;
 717
 718         *ptr = hwdev;
 719         devres_add(dev, ptr);
 720         return hwdev;
 721
 722 error:
 723         devres_free(ptr);
 724         return hwdev;
 725 }
 726 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);
 727
 728 /**
 729  * devm_hwmon_device_register_with_info - register w/ hwmon
 730  * @dev: the parent device
 731  * @name: hwmon name attribute
 732  * @drvdata: driver data to attach to created device
 733  * @info: Pointer to hwmon chip information
 734  * @groups - pointer to list of driver specific attribute groups
 735  *
 736  * Returns the pointer to the new device. The new device is automatically
 737  * unregistered with the parent device.
 738  */
 739 struct device *
 740 devm_hwmon_device_register_with_info(struct device *dev, const char *name,
 741                                      void *drvdata,
 742                                      const struct hwmon_chip_info *chip,
 743                                      const struct attribute_group **groups)
 744 {
 745         struct device **ptr, *hwdev;
 746
 747         if (!dev)
 748                 return ERR_PTR(-EINVAL);
 749
 750         ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
 751         if (!ptr)
 752                 return ERR_PTR(-ENOMEM);
 753
 754         hwdev = hwmon_device_register_with_info(dev, name, drvdata, chip,
 755                                                 groups);
 756         if (IS_ERR(hwdev))
 757                 goto error;
 758
 759         *ptr = hwdev;
 760         devres_add(dev, ptr);
 761
 762         return hwdev;
 763
 764 error:
 765         devres_free(ptr);
 766         return hwdev;
 767 }
 768 EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_info);
 769
 770 static int devm_hwmon_match(struct device *dev, void *res, void *data)
 771 {
 772         struct device **hwdev = res;
 773
 774         return *hwdev == data;
 775 }
 776
 777 /**
 778  * devm_hwmon_device_unregister - removes a previously registered hwmon device
 779  *
 780  * @dev: the parent device of the device to unregister
 781  */
 782 void devm_hwmon_device_unregister(struct device *dev)
 783 {
 784         WARN_ON(devres_release(dev, devm_hwmon_release, devm_hwmon_match, dev));
 785 }
 786 EXPORT_SYMBOL_GPL(devm_hwmon_device_unregister);
 787
 788 static void __init hwmon_pci_quirks(void)
 789 {
 790 #if defined CONFIG_X86 && defined CONFIG_PCI
 791         struct pci_dev *sb;
 792         u16 base;
 793         u8 enable;
 794
 795         /* Open access to 0x295-0x296 on MSI MS-7031 */
 796         sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
 797         if (sb) {
 798                 if (sb->subsystem_vendor == 0x1462 &&   /* MSI */
 799                     sb->subsystem_device == 0x0031) {   /* MS-7031 */
 800                         pci_read_config_byte(sb, 0x48, &enable);
 801                         pci_read_config_word(sb, 0x64, &base);
 802
 803                         if (base == 0 && !(enable & BIT(2))) {
 804                                 dev_info(&sb->dev,
 805                                          "Opening wide generic port at 0x295\n");
 806                                 pci_write_config_word(sb, 0x64, 0x295);
 807                                 pci_write_config_byte(sb, 0x48,
 808                                                       enable | BIT(2));
 809                         }
 810                 }
 811                 pci_dev_put(sb);
 812         }
 813 #endif
 814 }
 815
 816 static int __init hwmon_init(void)
 817 {
 818         int err;
 819
 820         hwmon_pci_quirks();
 821
 822         err = class_register(&hwmon_class);
 823         if (err) {
 824                 pr_err("couldn't register hwmon sysfs class\n");
 825                 return err;
 826         }
 827         return 0;
 828 }
 829
 830 static void __exit hwmon_exit(void)
 831 {
 832         class_unregister(&hwmon_class);
 833 }
 834
 835 subsys_initcall(hwmon_init);
 836 module_exit(hwmon_exit);
 837
 838 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
 839 MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
 840 MODULE_LICENSE("GPL");
 841