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