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 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 */
fan_get_max_state(struct thermal_cooling_device * cdev,unsigned long * state)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
acpi_fan_get_fst(struct acpi_device * device,struct acpi_fan_fst * fst)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
fan_get_state_acpi4(struct acpi_device * device,unsigned long * state)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
fan_get_state(struct acpi_device * device,unsigned long * state)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
fan_get_cur_state(struct thermal_cooling_device * cdev,unsigned long * state)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
fan_set_state(struct acpi_device * device,unsigned long state)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
fan_set_state_acpi4(struct acpi_device * device,unsigned long state)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
fan_set_cur_state(struct thermal_cooling_device * cdev,unsigned long state)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
acpi_fan_is_acpi4(struct acpi_device * device)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
acpi_fan_get_fif(struct acpi_device * device)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
acpi_fan_speed_cmp(const void * a,const void * b)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
acpi_fan_get_fps(struct acpi_device * device)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
acpi_fan_probe(struct platform_device * pdev)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 goto err_unregister;
373 }
374
375 result = sysfs_create_link(&cdev->device.kobj,
376 &pdev->dev.kobj,
377 "device");
378 if (result) {
379 dev_err(&pdev->dev, "Failed to create sysfs link 'device'\n");
380 goto err_remove_link;
381 }
382
383 return 0;
384
385 err_remove_link:
386 sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
387 err_unregister:
388 thermal_cooling_device_unregister(cdev);
389 err_end:
390 if (fan->acpi4)
391 acpi_fan_delete_attributes(device);
392
393 return result;
394 }
395
acpi_fan_remove(struct platform_device * pdev)396 static int acpi_fan_remove(struct platform_device *pdev)
397 {
398 struct acpi_fan *fan = platform_get_drvdata(pdev);
399
400 if (fan->acpi4) {
401 struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
402
403 acpi_fan_delete_attributes(device);
404 }
405 sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
406 sysfs_remove_link(&fan->cdev->device.kobj, "device");
407 thermal_cooling_device_unregister(fan->cdev);
408
409 return 0;
410 }
411
412 #ifdef CONFIG_PM_SLEEP
acpi_fan_suspend(struct device * dev)413 static int acpi_fan_suspend(struct device *dev)
414 {
415 struct acpi_fan *fan = dev_get_drvdata(dev);
416 if (fan->acpi4)
417 return 0;
418
419 acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D0);
420
421 return AE_OK;
422 }
423
acpi_fan_resume(struct device * dev)424 static int acpi_fan_resume(struct device *dev)
425 {
426 int result;
427 struct acpi_fan *fan = dev_get_drvdata(dev);
428
429 if (fan->acpi4)
430 return 0;
431
432 result = acpi_device_update_power(ACPI_COMPANION(dev), NULL);
433 if (result)
434 dev_err(dev, "Error updating fan power state\n");
435
436 return result;
437 }
438
439 static const struct dev_pm_ops acpi_fan_pm = {
440 .resume = acpi_fan_resume,
441 .freeze = acpi_fan_suspend,
442 .thaw = acpi_fan_resume,
443 .restore = acpi_fan_resume,
444 };
445 #define FAN_PM_OPS_PTR (&acpi_fan_pm)
446
447 #else
448
449 #define FAN_PM_OPS_PTR NULL
450
451 #endif
452
453 static struct platform_driver acpi_fan_driver = {
454 .probe = acpi_fan_probe,
455 .remove = acpi_fan_remove,
456 .driver = {
457 .name = "acpi-fan",
458 .acpi_match_table = fan_device_ids,
459 .pm = FAN_PM_OPS_PTR,
460 },
461 };
462
463 module_platform_driver(acpi_fan_driver);
464
465 MODULE_AUTHOR("Paul Diefenbaugh");
466 MODULE_DESCRIPTION("ACPI Fan Driver");
467 MODULE_LICENSE("GPL");
468