linux/drivers/acpi/fan.c
<<
>>
Prefs
   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
  32MODULE_AUTHOR("Paul Diefenbaugh");
  33MODULE_DESCRIPTION("ACPI Fan Driver");
  34MODULE_LICENSE("GPL");
  35
  36static int acpi_fan_probe(struct platform_device *pdev);
  37static int acpi_fan_remove(struct platform_device *pdev);
  38
  39static const struct acpi_device_id fan_device_ids[] = {
  40        {"PNP0C0B", 0},
  41        {"INT3404", 0},
  42        {"", 0},
  43};
  44MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  45
  46#ifdef CONFIG_PM_SLEEP
  47static int acpi_fan_suspend(struct device *dev);
  48static int acpi_fan_resume(struct device *dev);
  49static 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
  60struct acpi_fan_fps {
  61        u64 control;
  62        u64 trip_point;
  63        u64 speed;
  64        u64 noise_level;
  65        u64 power;
  66};
  67
  68struct acpi_fan_fif {
  69        u64 revision;
  70        u64 fine_grain_ctrl;
  71        u64 step_size;
  72        u64 low_speed_notification;
  73};
  74
  75struct 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
  83static 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 */
  94static 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
 107static 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
 153err:
 154        kfree(obj);
 155        return status;
 156}
 157
 158static 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
 173static 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
 185static 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
 194static 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
 212static int
 213fan_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
 224static 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
 235static 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
 243static 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
 269err:
 270        kfree(obj);
 271        return status;
 272}
 273
 274static 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
 281static 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_kcalloc(&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
 324err:
 325        kfree(obj);
 326        return status;
 327}
 328
 329static 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
 384end:
 385        return result;
 386}
 387
 388static 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
 400static 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
 411static 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
 427module_platform_driver(acpi_fan_driver);
 428