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
22static const struct acpi_device_id fan_device_ids[] = {
23 ACPI_FAN_DEVICE_IDS,
24 {.id: "", .driver_data: 0},
25};
26MODULE_DEVICE_TABLE(acpi, fan_device_ids);
27
28/* thermal cooling device callbacks */
29static 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(d: 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
47int 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(object: device->handle, pathname: "_FST", NULL, return_object_buffer: &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
73err:
74 kfree(objp: obj);
75 return ret;
76}
77
78static int fan_get_state_acpi4(struct acpi_device *device, unsigned long *state)
79{
80 struct acpi_fan *fan = acpi_driver_data(d: device);
81 struct acpi_fan_fst fst;
82 int status, i;
83
84 status = acpi_fan_get_fst(device, fst: &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
99match_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, "No matching fps control value\n");
106 return -EINVAL;
107 }
108
109 *state = i;
110
111 return status;
112}
113
114static 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, state_p: &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
129static 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(d: 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
141static 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: state ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
148}
149
150static int fan_set_state_acpi4(struct acpi_device *device, unsigned long state)
151{
152 struct acpi_fan *fan = acpi_driver_data(d: 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(handle: device->handle, method: "_FSL", arg: 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
183static int
184fan_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(d: 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
195static 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
206static int acpi_fan_get_fif(struct acpi_device *device)
207{
208 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
209 struct acpi_fan *fan = acpi_driver_data(d: device);
210 struct acpi_buffer format = { sizeof("NNNN"), "NNNN" };
211 u64 fields[4];
212 struct acpi_buffer fif = { sizeof(fields), fields };
213 union acpi_object *obj;
214 acpi_status status;
215
216 status = acpi_evaluate_object(object: device->handle, pathname: "_FIF", NULL, return_object_buffer: &buffer);
217 if (ACPI_FAILURE(status))
218 return status;
219
220 obj = buffer.pointer;
221 if (!obj || obj->type != ACPI_TYPE_PACKAGE) {
222 dev_err(&device->dev, "Invalid _FIF data\n");
223 status = -EINVAL;
224 goto err;
225 }
226
227 status = acpi_extract_package(package: obj, format: &format, buffer: &fif);
228 if (ACPI_FAILURE(status)) {
229 dev_err(&device->dev, "Invalid _FIF element\n");
230 status = -EINVAL;
231 goto err;
232 }
233
234 fan->fif.revision = fields[0];
235 fan->fif.fine_grain_ctrl = fields[1];
236 fan->fif.step_size = fields[2];
237 fan->fif.low_speed_notification = fields[3];
238
239 /* If there is a bug in step size and set as 0, change to 1 */
240 if (!fan->fif.step_size)
241 fan->fif.step_size = 1;
242 /* If step size > 9, change to 9 (by spec valid values 1-9) */
243 else if (fan->fif.step_size > 9)
244 fan->fif.step_size = 9;
245err:
246 kfree(objp: obj);
247 return status;
248}
249
250static int acpi_fan_speed_cmp(const void *a, const void *b)
251{
252 const struct acpi_fan_fps *fps1 = a;
253 const struct acpi_fan_fps *fps2 = b;
254 return fps1->speed - fps2->speed;
255}
256
257static int acpi_fan_get_fps(struct acpi_device *device)
258{
259 struct acpi_fan *fan = acpi_driver_data(d: device);
260 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
261 union acpi_object *obj;
262 acpi_status status;
263 int i;
264
265 status = acpi_evaluate_object(object: device->handle, pathname: "_FPS", NULL, return_object_buffer: &buffer);
266 if (ACPI_FAILURE(status))
267 return status;
268
269 obj = buffer.pointer;
270 if (!obj || obj->type != ACPI_TYPE_PACKAGE || obj->package.count < 2) {
271 dev_err(&device->dev, "Invalid _FPS data\n");
272 status = -EINVAL;
273 goto err;
274 }
275
276 fan->fps_count = obj->package.count - 1; /* minus revision field */
277 fan->fps = devm_kcalloc(dev: &device->dev,
278 n: fan->fps_count, size: sizeof(struct acpi_fan_fps),
279 GFP_KERNEL);
280 if (!fan->fps) {
281 dev_err(&device->dev, "Not enough memory\n");
282 status = -ENOMEM;
283 goto err;
284 }
285 for (i = 0; i < fan->fps_count; i++) {
286 struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
287 struct acpi_buffer fps = { offsetof(struct acpi_fan_fps, name),
288 &fan->fps[i] };
289 status = acpi_extract_package(package: &obj->package.elements[i + 1],
290 format: &format, buffer: &fps);
291 if (ACPI_FAILURE(status)) {
292 dev_err(&device->dev, "Invalid _FPS element\n");
293 goto err;
294 }
295 }
296
297 /* sort the state array according to fan speed in increase order */
298 sort(base: fan->fps, num: fan->fps_count, size: sizeof(*fan->fps),
299 cmp_func: acpi_fan_speed_cmp, NULL);
300
301err:
302 kfree(objp: obj);
303 return status;
304}
305
306static int acpi_fan_probe(struct platform_device *pdev)
307{
308 int result = 0;
309 struct thermal_cooling_device *cdev;
310 struct acpi_fan *fan;
311 struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
312 char *name;
313
314 fan = devm_kzalloc(dev: &pdev->dev, size: sizeof(*fan), GFP_KERNEL);
315 if (!fan) {
316 dev_err(&device->dev, "No memory for fan\n");
317 return -ENOMEM;
318 }
319 device->driver_data = fan;
320 platform_set_drvdata(pdev, data: fan);
321
322 if (acpi_has_method(handle: device->handle, name: "_FST")) {
323 fan->has_fst = true;
324 fan->acpi4 = acpi_has_method(handle: device->handle, name: "_FIF") &&
325 acpi_has_method(handle: device->handle, name: "_FPS") &&
326 acpi_has_method(handle: device->handle, name: "_FSL");
327 }
328
329 if (fan->acpi4) {
330 result = acpi_fan_get_fif(device);
331 if (result)
332 return result;
333
334 result = acpi_fan_get_fps(device);
335 if (result)
336 return result;
337 }
338
339 if (fan->has_fst) {
340 result = devm_acpi_fan_create_hwmon(device);
341 if (result)
342 return result;
343
344 result = acpi_fan_create_attributes(device);
345 if (result)
346 return result;
347 }
348
349 if (!fan->acpi4) {
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 err_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(ptr: cdev)) {
365 result = PTR_ERR(ptr: cdev);
366 goto err_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(kobj: &pdev->dev.kobj,
373 target: &cdev->device.kobj,
374 name: "thermal_cooling");
375 if (result) {
376 dev_err(&pdev->dev, "Failed to create sysfs link 'thermal_cooling'\n");
377 goto err_unregister;
378 }
379
380 result = sysfs_create_link(kobj: &cdev->device.kobj,
381 target: &pdev->dev.kobj,
382 name: "device");
383 if (result) {
384 dev_err(&pdev->dev, "Failed to create sysfs link 'device'\n");
385 goto err_remove_link;
386 }
387
388 return 0;
389
390err_remove_link:
391 sysfs_remove_link(kobj: &pdev->dev.kobj, name: "thermal_cooling");
392err_unregister:
393 thermal_cooling_device_unregister(cdev);
394err_end:
395 if (fan->has_fst)
396 acpi_fan_delete_attributes(device);
397
398 return result;
399}
400
401static void acpi_fan_remove(struct platform_device *pdev)
402{
403 struct acpi_fan *fan = platform_get_drvdata(pdev);
404
405 if (fan->has_fst) {
406 struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
407
408 acpi_fan_delete_attributes(device);
409 }
410 sysfs_remove_link(kobj: &pdev->dev.kobj, name: "thermal_cooling");
411 sysfs_remove_link(kobj: &fan->cdev->device.kobj, name: "device");
412 thermal_cooling_device_unregister(fan->cdev);
413}
414
415#ifdef CONFIG_PM_SLEEP
416static int acpi_fan_suspend(struct device *dev)
417{
418 struct acpi_fan *fan = dev_get_drvdata(dev);
419 if (fan->acpi4)
420 return 0;
421
422 acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D0);
423
424 return AE_OK;
425}
426
427static int acpi_fan_resume(struct device *dev)
428{
429 int result;
430 struct acpi_fan *fan = dev_get_drvdata(dev);
431
432 if (fan->acpi4)
433 return 0;
434
435 result = acpi_device_update_power(ACPI_COMPANION(dev), NULL);
436 if (result)
437 dev_err(dev, "Error updating fan power state\n");
438
439 return result;
440}
441
442static const struct dev_pm_ops acpi_fan_pm = {
443 .resume = acpi_fan_resume,
444 .freeze = acpi_fan_suspend,
445 .thaw = acpi_fan_resume,
446 .restore = acpi_fan_resume,
447};
448#define FAN_PM_OPS_PTR (&acpi_fan_pm)
449
450#else
451
452#define FAN_PM_OPS_PTR NULL
453
454#endif
455
456static struct platform_driver acpi_fan_driver = {
457 .probe = acpi_fan_probe,
458 .remove = acpi_fan_remove,
459 .driver = {
460 .name = "acpi-fan",
461 .acpi_match_table = fan_device_ids,
462 .pm = FAN_PM_OPS_PTR,
463 },
464};
465
466module_platform_driver(acpi_fan_driver);
467
468MODULE_AUTHOR("Paul Diefenbaugh");
469MODULE_DESCRIPTION("ACPI Fan Driver");
470MODULE_LICENSE("GPL");
471