drivers/acpi/fan.c

   1 /*
   2  *  acpi_fan.c - ACPI Fan Driver ($Revision: 29 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or (at
  12  *  your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful, but
  15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *  General Public License for more details.
  18  *
  19  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25 #include <linux/types.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/thermal.h>
  28 #include <linux/acpi.h>
  29 #include <linux/platform_device.h>
  30 #include <linux/sort.h>
  31
  32 MODULE_AUTHOR("Paul Diefenbaugh");
  33 MODULE_DESCRIPTION("ACPI Fan Driver");
  34 MODULE_LICENSE("GPL");
  35
  36 static int acpi_fan_probe(struct platform_device *pdev);
  37 static int acpi_fan_remove(struct platform_device *pdev);
  38
  39 static const struct acpi_device_id fan_device_ids[] = {
  40         {"PNP0C0B", 0},
  41         {"INT3404", 0},
  42         {"", 0},
  43 };
  44 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  45
  46 #ifdef CONFIG_PM_SLEEP
  47 static int acpi_fan_suspend(struct device *dev);
  48 static int acpi_fan_resume(struct device *dev);
  49 static const struct dev_pm_ops acpi_fan_pm = {
  50         .resume = acpi_fan_resume,
  51         .freeze = acpi_fan_suspend,
  52         .thaw = acpi_fan_resume,
  53         .restore = acpi_fan_resume,
  54 };
  55 #define FAN_PM_OPS_PTR (&acpi_fan_pm)
  56 #else
  57 #define FAN_PM_OPS_PTR NULL
  58 #endif
  59
  60 struct acpi_fan_fps {
  61         u64 control;
  62         u64 trip_point;
  63         u64 speed;
  64         u64 noise_level;
  65         u64 power;
  66 };
  67
  68 struct acpi_fan_fif {
  69         u64 revision;
  70         u64 fine_grain_ctrl;
  71         u64 step_size;
  72         u64 low_speed_notification;
  73 };
  74
  75 struct acpi_fan {
  76         bool acpi4;
  77         struct acpi_fan_fif fif;
  78         struct acpi_fan_fps *fps;
  79         int fps_count;
  80         struct thermal_cooling_device *cdev;
  81 };
  82
  83 static struct platform_driver acpi_fan_driver = {
  84         .probe = acpi_fan_probe,
  85         .remove = acpi_fan_remove,
  86         .driver = {
  87                 .name = "acpi-fan",
  88                 .acpi_match_table = fan_device_ids,
  89                 .pm = FAN_PM_OPS_PTR,
  90         },
  91 };
  92
  93 /* thermal cooling device callbacks */
  94 static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
  95                              *state)
  96 {
  97         struct acpi_device *device = cdev->devdata;
  98         struct acpi_fan *fan = acpi_driver_data(device);
  99
 100         if (fan->acpi4)
 101                 *state = fan->fps_count - 1;
 102         else
 103                 *state = 1;
 104         return 0;
 105 }
 106
 107 static int fan_get_state_acpi4(struct acpi_device *device, unsigned long *state)
 108 {
 109         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 110         struct acpi_fan *fan = acpi_driver_data(device);
 111         union acpi_object *obj;
 112         acpi_status status;
 113         int control, i;
 114
 115         status = acpi_evaluate_object(device->handle, "_FST", NULL, &buffer);
 116         if (ACPI_FAILURE(status)) {
 117                 dev_err(&device->dev, "Get fan state failed\n");
 118                 return status;
 119         }
 120
 121         obj = buffer.pointer;
 122         if (!obj || obj->type != ACPI_TYPE_PACKAGE ||
 123             obj->package.count != 3 ||
 124             obj->package.elements[1].type != ACPI_TYPE_INTEGER) {
 125                 dev_err(&device->dev, "Invalid _FST data\n");
 126                 status = -EINVAL;
 127                 goto err;
 128         }
 129
 130         control = obj->package.elements[1].integer.value;
 131         for (i = 0; i < fan->fps_count; i++) {
 132                 /*
 133                  * When Fine Grain Control is set, return the state
 134                  * corresponding to maximum fan->fps[i].control
 135                  * value compared to the current speed. Here the
 136                  * fan->fps[] is sorted array with increasing speed.
 137                  */
 138                 if (fan->fif.fine_grain_ctrl && control < fan->fps[i].control) {
 139                         i = (i > 0) ? i - 1 : 0;
 140                         break;
 141                 } else if (control == fan->fps[i].control) {
 142                         break;
 143                 }
 144         }
 145         if (i == fan->fps_count) {
 146                 dev_dbg(&device->dev, "Invalid control value returned\n");
 147                 status = -EINVAL;
 148                 goto err;
 149         }
 150
 151         *state = i;
 152
 153 err:
 154         kfree(obj);
 155         return status;
 156 }
 157
 158 static int fan_get_state(struct acpi_device *device, unsigned long *state)
 159 {
 160         int result;
 161         int acpi_state = ACPI_STATE_D0;
 162
 163         result = acpi_device_update_power(device, &acpi_state);
 164         if (result)
 165                 return result;
 166
 167         *state = acpi_state == ACPI_STATE_D3_COLD
 168                         || acpi_state == ACPI_STATE_D3_HOT ?
 169                 0 : (acpi_state == ACPI_STATE_D0 ? 1 : -1);
 170         return 0;
 171 }
 172
 173 static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
 174                              *state)
 175 {
 176         struct acpi_device *device = cdev->devdata;
 177         struct acpi_fan *fan = acpi_driver_data(device);
 178
 179         if (fan->acpi4)
 180                 return fan_get_state_acpi4(device, state);
 181         else
 182                 return fan_get_state(device, state);
 183 }
 184
 185 static int fan_set_state(struct acpi_device *device, unsigned long state)
 186 {
 187         if (state != 0 && state != 1)
 188                 return -EINVAL;
 189
 190         return acpi_device_set_power(device,
 191                                      state ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
 192 }
 193
 194 static int fan_set_state_acpi4(struct acpi_device *device, unsigned long state)
 195 {
 196         struct acpi_fan *fan = acpi_driver_data(device);
 197         acpi_status status;
 198
 199         if (state >= fan->fps_count)
 200                 return -EINVAL;
 201
 202         status = acpi_execute_simple_method(device->handle, "_FSL",
 203                                             fan->fps[state].control);
 204         if (ACPI_FAILURE(status)) {
 205                 dev_dbg(&device->dev, "Failed to set state by _FSL\n");
 206                 return status;
 207         }
 208
 209         return 0;
 210 }
 211
 212 static int
 213 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
 214 {
 215         struct acpi_device *device = cdev->devdata;
 216         struct acpi_fan *fan = acpi_driver_data(device);
 217
 218         if (fan->acpi4)
 219                 return fan_set_state_acpi4(device, state);
 220         else
 221                 return fan_set_state(device, state);
 222  }
 223
 224 static const struct thermal_cooling_device_ops fan_cooling_ops = {
 225         .get_max_state = fan_get_max_state,
 226         .get_cur_state = fan_get_cur_state,
 227         .set_cur_state = fan_set_cur_state,
 228 };
 229
 230 /* --------------------------------------------------------------------------
 231  *                               Driver Interface
 232  * --------------------------------------------------------------------------
 233 */
 234
 235 static bool acpi_fan_is_acpi4(struct acpi_device *device)
 236 {
 237         return acpi_has_method(device->handle, "_FIF") &&
 238                acpi_has_method(device->handle, "_FPS") &&
 239                acpi_has_method(device->handle, "_FSL") &&
 240                acpi_has_method(device->handle, "_FST");
 241 }
 242
 243 static int acpi_fan_get_fif(struct acpi_device *device)
 244 {
 245         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 246         struct acpi_fan *fan = acpi_driver_data(device);
 247         struct acpi_buffer format = { sizeof("NNNN"), "NNNN" };
 248         struct acpi_buffer fif = { sizeof(fan->fif), &fan->fif };
 249         union acpi_object *obj;
 250         acpi_status status;
 251
 252         status = acpi_evaluate_object(device->handle, "_FIF", NULL, &buffer);
 253         if (ACPI_FAILURE(status))
 254                 return status;
 255
 256         obj = buffer.pointer;
 257         if (!obj || obj->type != ACPI_TYPE_PACKAGE) {
 258                 dev_err(&device->dev, "Invalid _FIF data\n");
 259                 status = -EINVAL;
 260                 goto err;
 261         }
 262
 263         status = acpi_extract_package(obj, &format, &fif);
 264         if (ACPI_FAILURE(status)) {
 265                 dev_err(&device->dev, "Invalid _FIF element\n");
 266                 status = -EINVAL;
 267         }
 268
 269 err:
 270         kfree(obj);
 271         return status;
 272 }
 273
 274 static int acpi_fan_speed_cmp(const void *a, const void *b)
 275 {
 276         const struct acpi_fan_fps *fps1 = a;
 277         const struct acpi_fan_fps *fps2 = b;
 278         return fps1->speed - fps2->speed;
 279 }
 280
 281 static int acpi_fan_get_fps(struct acpi_device *device)
 282 {
 283         struct acpi_fan *fan = acpi_driver_data(device);
 284         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 285         union acpi_object *obj;
 286         acpi_status status;
 287         int i;
 288
 289         status = acpi_evaluate_object(device->handle, "_FPS", NULL, &buffer);
 290         if (ACPI_FAILURE(status))
 291                 return status;
 292
 293         obj = buffer.pointer;
 294         if (!obj || obj->type != ACPI_TYPE_PACKAGE || obj->package.count < 2) {
 295                 dev_err(&device->dev, "Invalid _FPS data\n");
 296                 status = -EINVAL;
 297                 goto err;
 298         }
 299
 300         fan->fps_count = obj->package.count - 1; /* minus revision field */
 301         fan->fps = devm_kzalloc(&device->dev,
 302                                 fan->fps_count * sizeof(struct acpi_fan_fps),
 303                                 GFP_KERNEL);
 304         if (!fan->fps) {
 305                 dev_err(&device->dev, "Not enough memory\n");
 306                 status = -ENOMEM;
 307                 goto err;
 308         }
 309         for (i = 0; i < fan->fps_count; i++) {
 310                 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
 311                 struct acpi_buffer fps = { sizeof(fan->fps[i]), &fan->fps[i] };
 312                 status = acpi_extract_package(&obj->package.elements[i + 1],
 313                                               &format, &fps);
 314                 if (ACPI_FAILURE(status)) {
 315                         dev_err(&device->dev, "Invalid _FPS element\n");
 316                         break;
 317                 }
 318         }
 319
 320         /* sort the state array according to fan speed in increase order */
 321         sort(fan->fps, fan->fps_count, sizeof(*fan->fps),
 322              acpi_fan_speed_cmp, NULL);
 323
 324 err:
 325         kfree(obj);
 326         return status;
 327 }
 328
 329 static int acpi_fan_probe(struct platform_device *pdev)
 330 {
 331         int result = 0;
 332         struct thermal_cooling_device *cdev;
 333         struct acpi_fan *fan;
 334         struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
 335         char *name;
 336
 337         fan = devm_kzalloc(&pdev->dev, sizeof(*fan), GFP_KERNEL);
 338         if (!fan) {
 339                 dev_err(&device->dev, "No memory for fan\n");
 340                 return -ENOMEM;
 341         }
 342         device->driver_data = fan;
 343         platform_set_drvdata(pdev, fan);
 344
 345         if (acpi_fan_is_acpi4(device)) {
 346                 if (acpi_fan_get_fif(device) || acpi_fan_get_fps(device))
 347                         goto end;
 348                 fan->acpi4 = true;
 349         } else {
 350                 result = acpi_device_update_power(device, NULL);
 351                 if (result) {
 352                         dev_err(&device->dev, "Failed to set initial power state\n");
 353                         goto end;
 354                 }
 355         }
 356
 357         if (!strncmp(pdev->name, "PNP0C0B", strlen("PNP0C0B")))
 358                 name = "Fan";
 359         else
 360                 name = acpi_device_bid(device);
 361
 362         cdev = thermal_cooling_device_register(name, device,
 363                                                 &fan_cooling_ops);
 364         if (IS_ERR(cdev)) {
 365                 result = PTR_ERR(cdev);
 366                 goto end;
 367         }
 368
 369         dev_dbg(&pdev->dev, "registered as cooling_device%d\n", cdev->id);
 370
 371         fan->cdev = cdev;
 372         result = sysfs_create_link(&pdev->dev.kobj,
 373                                    &cdev->device.kobj,
 374                                    "thermal_cooling");
 375         if (result)
 376                 dev_err(&pdev->dev, "Failed to create sysfs link 'thermal_cooling'\n");
 377
 378         result = sysfs_create_link(&cdev->device.kobj,
 379                                    &pdev->dev.kobj,
 380                                    "device");
 381         if (result)
 382                 dev_err(&pdev->dev, "Failed to create sysfs link 'device'\n");
 383
 384 end:
 385         return result;
 386 }
 387
 388 static int acpi_fan_remove(struct platform_device *pdev)
 389 {
 390         struct acpi_fan *fan = platform_get_drvdata(pdev);
 391
 392         sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
 393         sysfs_remove_link(&fan->cdev->device.kobj, "device");
 394         thermal_cooling_device_unregister(fan->cdev);
 395
 396         return 0;
 397 }
 398
 399 #ifdef CONFIG_PM_SLEEP
 400 static int acpi_fan_suspend(struct device *dev)
 401 {
 402         struct acpi_fan *fan = dev_get_drvdata(dev);
 403         if (fan->acpi4)
 404                 return 0;
 405
 406         acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D0);
 407
 408         return AE_OK;
 409 }
 410
 411 static int acpi_fan_resume(struct device *dev)
 412 {
 413         int result;
 414         struct acpi_fan *fan = dev_get_drvdata(dev);
 415
 416         if (fan->acpi4)
 417                 return 0;
 418
 419         result = acpi_device_update_power(ACPI_COMPANION(dev), NULL);
 420         if (result)
 421                 dev_err(dev, "Error updating fan power state\n");
 422
 423         return result;
 424 }
 425 #endif
 426
 427 module_platform_driver(acpi_fan_driver);