drivers/acpi/fan_core.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  fan_core.c - ACPI Fan core Driver
   4  *
   5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7  *  Copyright (C) 2022 Intel Corporation. All rights reserved.
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/types.h>
  14 #include <linux/uaccess.h>
  15 #include <linux/thermal.h>
  16 #include <linux/acpi.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/sort.h>
  19
  20 #include "fan.h"
  21
  22 MODULE_AUTHOR("Paul Diefenbaugh");
  23 MODULE_DESCRIPTION("ACPI Fan Driver");
  24 MODULE_LICENSE("GPL");
  25
  26 static int acpi_fan_probe(struct platform_device *pdev);
  27 static int acpi_fan_remove(struct platform_device *pdev);
  28
  29 static const struct acpi_device_id fan_device_ids[] = {
  30         ACPI_FAN_DEVICE_IDS,
  31         {"", 0},
  32 };
  33 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  34
  35 #ifdef CONFIG_PM_SLEEP
  36 static int acpi_fan_suspend(struct device *dev);
  37 static int acpi_fan_resume(struct device *dev);
  38 static const struct dev_pm_ops acpi_fan_pm = {
  39         .resume = acpi_fan_resume,
  40         .freeze = acpi_fan_suspend,
  41         .thaw = acpi_fan_resume,
  42         .restore = acpi_fan_resume,
  43 };
  44 #define FAN_PM_OPS_PTR (&acpi_fan_pm)
  45 #else
  46 #define FAN_PM_OPS_PTR NULL
  47 #endif
  48
  49 static struct platform_driver acpi_fan_driver = {
  50         .probe = acpi_fan_probe,
  51         .remove = acpi_fan_remove,
  52         .driver = {
  53                 .name = "acpi-fan",
  54                 .acpi_match_table = fan_device_ids,
  55                 .pm = FAN_PM_OPS_PTR,
  56         },
  57 };
  58
  59 /* thermal cooling device callbacks */
  60 static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
  61                              *state)
  62 {
  63         struct acpi_device *device = cdev->devdata;
  64         struct acpi_fan *fan = acpi_driver_data(device);
  65
  66         if (fan->acpi4) {
  67                 if (fan->fif.fine_grain_ctrl)
  68                         *state = 100 / fan->fif.step_size;
  69                 else
  70                         *state = fan->fps_count - 1;
  71         } else {
  72                 *state = 1;
  73         }
  74
  75         return 0;
  76 }
  77
  78 int acpi_fan_get_fst(struct acpi_device *device, struct acpi_fan_fst *fst)
  79 {
  80         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
  81         union acpi_object *obj;
  82         acpi_status status;
  83         int ret = 0;
  84
  85         status = acpi_evaluate_object(device->handle, "_FST", NULL, &buffer);
  86         if (ACPI_FAILURE(status)) {
  87                 dev_err(&device->dev, "Get fan state failed\n");
  88                 return -ENODEV;
  89         }
  90
  91         obj = buffer.pointer;
  92         if (!obj || obj->type != ACPI_TYPE_PACKAGE ||
  93             obj->package.count != 3 ||
  94             obj->package.elements[1].type != ACPI_TYPE_INTEGER) {
  95                 dev_err(&device->dev, "Invalid _FST data\n");
  96                 ret = -EINVAL;
  97                 goto err;
  98         }
  99
 100         fst->revision = obj->package.elements[0].integer.value;
 101         fst->control = obj->package.elements[1].integer.value;
 102         fst->speed = obj->package.elements[2].integer.value;
 103
 104 err:
 105         kfree(obj);
 106         return ret;
 107 }
 108
 109 static int fan_get_state_acpi4(struct acpi_device *device, unsigned long *state)
 110 {
 111         struct acpi_fan *fan = acpi_driver_data(device);
 112         struct acpi_fan_fst fst;
 113         int status, i;
 114
 115         status = acpi_fan_get_fst(device, &fst);
 116         if (status)
 117                 return status;
 118
 119         if (fan->fif.fine_grain_ctrl) {
 120                 /* This control should be same what we set using _FSL by spec */
 121                 if (fst.control > 100) {
 122                         dev_dbg(&device->dev, "Invalid control value returned\n");
 123                         goto match_fps;
 124                 }
 125
 126                 *state = (int) fst.control / fan->fif.step_size;
 127                 return 0;
 128         }
 129
 130 match_fps:
 131         for (i = 0; i < fan->fps_count; i++) {
 132                 if (fst.control == fan->fps[i].control)
 133                         break;
 134         }
 135         if (i == fan->fps_count) {
 136                 dev_dbg(&device->dev, "Invalid control value returned\n");
 137                 return -EINVAL;
 138         }
 139
 140         *state = i;
 141
 142         return status;
 143 }
 144
 145 static int fan_get_state(struct acpi_device *device, unsigned long *state)
 146 {
 147         int result;
 148         int acpi_state = ACPI_STATE_D0;
 149
 150         result = acpi_device_update_power(device, &acpi_state);
 151         if (result)
 152                 return result;
 153
 154         *state = acpi_state == ACPI_STATE_D3_COLD
 155                         || acpi_state == ACPI_STATE_D3_HOT ?
 156                 0 : (acpi_state == ACPI_STATE_D0 ? 1 : -1);
 157         return 0;
 158 }
 159
 160 static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
 161                              *state)
 162 {
 163         struct acpi_device *device = cdev->devdata;
 164         struct acpi_fan *fan = acpi_driver_data(device);
 165
 166         if (fan->acpi4)
 167                 return fan_get_state_acpi4(device, state);
 168         else
 169                 return fan_get_state(device, state);
 170 }
 171
 172 static int fan_set_state(struct acpi_device *device, unsigned long state)
 173 {
 174         if (state != 0 && state != 1)
 175                 return -EINVAL;
 176
 177         return acpi_device_set_power(device,
 178                                      state ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
 179 }
 180
 181 static int fan_set_state_acpi4(struct acpi_device *device, unsigned long state)
 182 {
 183         struct acpi_fan *fan = acpi_driver_data(device);
 184         acpi_status status;
 185         u64 value = state;
 186         int max_state;
 187
 188         if (fan->fif.fine_grain_ctrl)
 189                 max_state = 100 / fan->fif.step_size;
 190         else
 191                 max_state = fan->fps_count - 1;
 192
 193         if (state > max_state)
 194                 return -EINVAL;
 195
 196         if (fan->fif.fine_grain_ctrl) {
 197                 value *= fan->fif.step_size;
 198                 /* Spec allows compensate the last step only */
 199                 if (value + fan->fif.step_size > 100)
 200                         value = 100;
 201         } else {
 202                 value = fan->fps[state].control;
 203         }
 204
 205         status = acpi_execute_simple_method(device->handle, "_FSL", value);
 206         if (ACPI_FAILURE(status)) {
 207                 dev_dbg(&device->dev, "Failed to set state by _FSL\n");
 208                 return -ENODEV;
 209         }
 210
 211         return 0;
 212 }
 213
 214 static int
 215 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
 216 {
 217         struct acpi_device *device = cdev->devdata;
 218         struct acpi_fan *fan = acpi_driver_data(device);
 219
 220         if (fan->acpi4)
 221                 return fan_set_state_acpi4(device, state);
 222         else
 223                 return fan_set_state(device, state);
 224 }
 225
 226 static const struct thermal_cooling_device_ops fan_cooling_ops = {
 227         .get_max_state = fan_get_max_state,
 228         .get_cur_state = fan_get_cur_state,
 229         .set_cur_state = fan_set_cur_state,
 230 };
 231
 232 /* --------------------------------------------------------------------------
 233  *                               Driver Interface
 234  * --------------------------------------------------------------------------
 235 */
 236
 237 static bool acpi_fan_is_acpi4(struct acpi_device *device)
 238 {
 239         return acpi_has_method(device->handle, "_FIF") &&
 240                acpi_has_method(device->handle, "_FPS") &&
 241                acpi_has_method(device->handle, "_FSL") &&
 242                acpi_has_method(device->handle, "_FST");
 243 }
 244
 245 static int acpi_fan_get_fif(struct acpi_device *device)
 246 {
 247         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 248         struct acpi_fan *fan = acpi_driver_data(device);
 249         struct acpi_buffer format = { sizeof("NNNN"), "NNNN" };
 250         u64 fields[4];
 251         struct acpi_buffer fif = { sizeof(fields), fields };
 252         union acpi_object *obj;
 253         acpi_status status;
 254
 255         status = acpi_evaluate_object(device->handle, "_FIF", NULL, &buffer);
 256         if (ACPI_FAILURE(status))
 257                 return status;
 258
 259         obj = buffer.pointer;
 260         if (!obj || obj->type != ACPI_TYPE_PACKAGE) {
 261                 dev_err(&device->dev, "Invalid _FIF data\n");
 262                 status = -EINVAL;
 263                 goto err;
 264         }
 265
 266         status = acpi_extract_package(obj, &format, &fif);
 267         if (ACPI_FAILURE(status)) {
 268                 dev_err(&device->dev, "Invalid _FIF element\n");
 269                 status = -EINVAL;
 270         }
 271
 272         fan->fif.revision = fields[0];
 273         fan->fif.fine_grain_ctrl = fields[1];
 274         fan->fif.step_size = fields[2];
 275         fan->fif.low_speed_notification = fields[3];
 276
 277         /* If there is a bug in step size and set as 0, change to 1 */
 278         if (!fan->fif.step_size)
 279                 fan->fif.step_size = 1;
 280         /* If step size > 9, change to 9 (by spec valid values 1-9) */
 281         else if (fan->fif.step_size > 9)
 282                 fan->fif.step_size = 9;
 283 err:
 284         kfree(obj);
 285         return status;
 286 }
 287
 288 static int acpi_fan_speed_cmp(const void *a, const void *b)
 289 {
 290         const struct acpi_fan_fps *fps1 = a;
 291         const struct acpi_fan_fps *fps2 = b;
 292         return fps1->speed - fps2->speed;
 293 }
 294
 295 static int acpi_fan_get_fps(struct acpi_device *device)
 296 {
 297         struct acpi_fan *fan = acpi_driver_data(device);
 298         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 299         union acpi_object *obj;
 300         acpi_status status;
 301         int i;
 302
 303         status = acpi_evaluate_object(device->handle, "_FPS", NULL, &buffer);
 304         if (ACPI_FAILURE(status))
 305                 return status;
 306
 307         obj = buffer.pointer;
 308         if (!obj || obj->type != ACPI_TYPE_PACKAGE || obj->package.count < 2) {
 309                 dev_err(&device->dev, "Invalid _FPS data\n");
 310                 status = -EINVAL;
 311                 goto err;
 312         }
 313
 314         fan->fps_count = obj->package.count - 1; /* minus revision field */
 315         fan->fps = devm_kcalloc(&device->dev,
 316                                 fan->fps_count, sizeof(struct acpi_fan_fps),
 317                                 GFP_KERNEL);
 318         if (!fan->fps) {
 319                 dev_err(&device->dev, "Not enough memory\n");
 320                 status = -ENOMEM;
 321                 goto err;
 322         }
 323         for (i = 0; i < fan->fps_count; i++) {
 324                 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
 325                 struct acpi_buffer fps = { offsetof(struct acpi_fan_fps, name),
 326                                                 &fan->fps[i] };
 327                 status = acpi_extract_package(&obj->package.elements[i + 1],
 328                                               &format, &fps);
 329                 if (ACPI_FAILURE(status)) {
 330                         dev_err(&device->dev, "Invalid _FPS element\n");
 331                         goto err;
 332                 }
 333         }
 334
 335         /* sort the state array according to fan speed in increase order */
 336         sort(fan->fps, fan->fps_count, sizeof(*fan->fps),
 337              acpi_fan_speed_cmp, NULL);
 338
 339 err:
 340         kfree(obj);
 341         return status;
 342 }
 343
 344 static int acpi_fan_probe(struct platform_device *pdev)
 345 {
 346         int result = 0;
 347         struct thermal_cooling_device *cdev;
 348         struct acpi_fan *fan;
 349         struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
 350         char *name;
 351
 352         fan = devm_kzalloc(&pdev->dev, sizeof(*fan), GFP_KERNEL);
 353         if (!fan) {
 354                 dev_err(&device->dev, "No memory for fan\n");
 355                 return -ENOMEM;
 356         }
 357         device->driver_data = fan;
 358         platform_set_drvdata(pdev, fan);
 359
 360         if (acpi_fan_is_acpi4(device)) {
 361                 result = acpi_fan_get_fif(device);
 362                 if (result)
 363                         return result;
 364
 365                 result = acpi_fan_get_fps(device);
 366                 if (result)
 367                         return result;
 368
 369                 result = acpi_fan_create_attributes(device);
 370                 if (result)
 371                         return result;
 372
 373                 fan->acpi4 = true;
 374         } else {
 375                 result = acpi_device_update_power(device, NULL);
 376                 if (result) {
 377                         dev_err(&device->dev, "Failed to set initial power state\n");
 378                         goto err_end;
 379                 }
 380         }
 381
 382         if (!strncmp(pdev->name, "PNP0C0B", strlen("PNP0C0B")))
 383                 name = "Fan";
 384         else
 385                 name = acpi_device_bid(device);
 386
 387         cdev = thermal_cooling_device_register(name, device,
 388                                                 &fan_cooling_ops);
 389         if (IS_ERR(cdev)) {
 390                 result = PTR_ERR(cdev);
 391                 goto err_end;
 392         }
 393
 394         dev_dbg(&pdev->dev, "registered as cooling_device%d\n", cdev->id);
 395
 396         fan->cdev = cdev;
 397         result = sysfs_create_link(&pdev->dev.kobj,
 398                                    &cdev->device.kobj,
 399                                    "thermal_cooling");
 400         if (result)
 401                 dev_err(&pdev->dev, "Failed to create sysfs link 'thermal_cooling'\n");
 402
 403         result = sysfs_create_link(&cdev->device.kobj,
 404                                    &pdev->dev.kobj,
 405                                    "device");
 406         if (result) {
 407                 dev_err(&pdev->dev, "Failed to create sysfs link 'device'\n");
 408                 goto err_end;
 409         }
 410
 411         return 0;
 412
 413 err_end:
 414         if (fan->acpi4)
 415                 acpi_fan_delete_attributes(device);
 416
 417         return result;
 418 }
 419
 420 static int acpi_fan_remove(struct platform_device *pdev)
 421 {
 422         struct acpi_fan *fan = platform_get_drvdata(pdev);
 423
 424         if (fan->acpi4) {
 425                 struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
 426
 427                 acpi_fan_delete_attributes(device);
 428         }
 429         sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
 430         sysfs_remove_link(&fan->cdev->device.kobj, "device");
 431         thermal_cooling_device_unregister(fan->cdev);
 432
 433         return 0;
 434 }
 435
 436 #ifdef CONFIG_PM_SLEEP
 437 static int acpi_fan_suspend(struct device *dev)
 438 {
 439         struct acpi_fan *fan = dev_get_drvdata(dev);
 440         if (fan->acpi4)
 441                 return 0;
 442
 443         acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D0);
 444
 445         return AE_OK;
 446 }
 447
 448 static int acpi_fan_resume(struct device *dev)
 449 {
 450         int result;
 451         struct acpi_fan *fan = dev_get_drvdata(dev);
 452
 453         if (fan->acpi4)
 454                 return 0;
 455
 456         result = acpi_device_update_power(ACPI_COMPANION(dev), NULL);
 457         if (result)
 458                 dev_err(dev, "Error updating fan power state\n");
 459
 460         return result;
 461 }
 462 #endif
 463
 464 module_platform_driver(acpi_fan_driver);