xref: /linux/drivers/acpi/fan_core.c (revision 09b1704f5b02c18dd02b21343530463fcfc92c54)
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 */
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(acpi_handle handle, 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(handle, "_FST", NULL, &buffer);
55 	if (ACPI_FAILURE(status))
56 		return -EIO;
57 
58 	obj = buffer.pointer;
59 	if (!obj)
60 		return -ENODATA;
61 
62 	if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count != 3) {
63 		ret = -EPROTO;
64 		goto err;
65 	}
66 
67 	if (obj->package.elements[0].type != ACPI_TYPE_INTEGER ||
68 	    obj->package.elements[1].type != ACPI_TYPE_INTEGER ||
69 	    obj->package.elements[2].type != ACPI_TYPE_INTEGER) {
70 		ret = -EPROTO;
71 		goto err;
72 	}
73 
74 	fst->revision = obj->package.elements[0].integer.value;
75 	fst->control = obj->package.elements[1].integer.value;
76 	fst->speed = obj->package.elements[2].integer.value;
77 
78 err:
79 	kfree(obj);
80 	return ret;
81 }
82 
83 static int fan_get_state_acpi4(struct acpi_device *device, unsigned long *state)
84 {
85 	struct acpi_fan *fan = acpi_driver_data(device);
86 	struct acpi_fan_fst fst;
87 	int status, i;
88 
89 	status = acpi_fan_get_fst(device->handle, &fst);
90 	if (status)
91 		return status;
92 
93 	if (fan->fif.fine_grain_ctrl) {
94 		/* This control should be same what we set using _FSL by spec */
95 		if (fst.control > 100) {
96 			dev_dbg(&device->dev, "Invalid control value returned\n");
97 			goto match_fps;
98 		}
99 
100 		*state = (int) fst.control / fan->fif.step_size;
101 		return 0;
102 	}
103 
104 match_fps:
105 	for (i = 0; i < fan->fps_count; i++) {
106 		if (fst.control == fan->fps[i].control)
107 			break;
108 	}
109 	if (i == fan->fps_count) {
110 		dev_dbg(&device->dev, "No matching fps control value\n");
111 		return -EINVAL;
112 	}
113 
114 	*state = i;
115 
116 	return status;
117 }
118 
119 static int fan_get_state(struct acpi_device *device, unsigned long *state)
120 {
121 	int result;
122 	int acpi_state = ACPI_STATE_D0;
123 
124 	result = acpi_device_update_power(device, &acpi_state);
125 	if (result)
126 		return result;
127 
128 	*state = acpi_state == ACPI_STATE_D3_COLD
129 			|| acpi_state == ACPI_STATE_D3_HOT ?
130 		0 : (acpi_state == ACPI_STATE_D0 ? 1 : -1);
131 	return 0;
132 }
133 
134 static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
135 			     *state)
136 {
137 	struct acpi_device *device = cdev->devdata;
138 	struct acpi_fan *fan = acpi_driver_data(device);
139 
140 	if (fan->acpi4)
141 		return fan_get_state_acpi4(device, state);
142 	else
143 		return fan_get_state(device, state);
144 }
145 
146 static int fan_set_state(struct acpi_device *device, unsigned long state)
147 {
148 	if (state != 0 && state != 1)
149 		return -EINVAL;
150 
151 	return acpi_device_set_power(device,
152 				     state ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
153 }
154 
155 static int fan_set_state_acpi4(struct acpi_device *device, unsigned long state)
156 {
157 	struct acpi_fan *fan = acpi_driver_data(device);
158 	acpi_status status;
159 	u64 value = state;
160 	int max_state;
161 
162 	if (fan->fif.fine_grain_ctrl)
163 		max_state = 100 / fan->fif.step_size;
164 	else
165 		max_state = fan->fps_count - 1;
166 
167 	if (state > max_state)
168 		return -EINVAL;
169 
170 	if (fan->fif.fine_grain_ctrl) {
171 		value *= fan->fif.step_size;
172 		/* Spec allows compensate the last step only */
173 		if (value + fan->fif.step_size > 100)
174 			value = 100;
175 	} else {
176 		value = fan->fps[state].control;
177 	}
178 
179 	status = acpi_execute_simple_method(device->handle, "_FSL", value);
180 	if (ACPI_FAILURE(status)) {
181 		dev_dbg(&device->dev, "Failed to set state by _FSL\n");
182 		return -ENODEV;
183 	}
184 
185 	return 0;
186 }
187 
188 static int
189 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
190 {
191 	struct acpi_device *device = cdev->devdata;
192 	struct acpi_fan *fan = acpi_driver_data(device);
193 
194 	if (fan->acpi4)
195 		return fan_set_state_acpi4(device, state);
196 	else
197 		return fan_set_state(device, state);
198 }
199 
200 static const struct thermal_cooling_device_ops fan_cooling_ops = {
201 	.get_max_state = fan_get_max_state,
202 	.get_cur_state = fan_get_cur_state,
203 	.set_cur_state = fan_set_cur_state,
204 };
205 
206 /* --------------------------------------------------------------------------
207  *                               Driver Interface
208  * --------------------------------------------------------------------------
209 */
210 
211 static int acpi_fan_get_fif(struct acpi_device *device)
212 {
213 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
214 	struct acpi_fan *fan = acpi_driver_data(device);
215 	struct acpi_buffer format = { sizeof("NNNN"), "NNNN" };
216 	u64 fields[4];
217 	struct acpi_buffer fif = { sizeof(fields), fields };
218 	union acpi_object *obj;
219 	acpi_status status;
220 
221 	status = acpi_evaluate_object(device->handle, "_FIF", NULL, &buffer);
222 	if (ACPI_FAILURE(status))
223 		return status;
224 
225 	obj = buffer.pointer;
226 	if (!obj || obj->type != ACPI_TYPE_PACKAGE) {
227 		dev_err(&device->dev, "Invalid _FIF data\n");
228 		status = -EINVAL;
229 		goto err;
230 	}
231 
232 	status = acpi_extract_package(obj, &format, &fif);
233 	if (ACPI_FAILURE(status)) {
234 		dev_err(&device->dev, "Invalid _FIF element\n");
235 		status = -EINVAL;
236 		goto err;
237 	}
238 
239 	fan->fif.revision = fields[0];
240 	fan->fif.fine_grain_ctrl = fields[1];
241 	fan->fif.step_size = fields[2];
242 	fan->fif.low_speed_notification = fields[3];
243 
244 	/* If there is a bug in step size and set as 0, change to 1 */
245 	if (!fan->fif.step_size)
246 		fan->fif.step_size = 1;
247 	/* If step size > 9, change to 9 (by spec valid values 1-9) */
248 	else if (fan->fif.step_size > 9)
249 		fan->fif.step_size = 9;
250 err:
251 	kfree(obj);
252 	return status;
253 }
254 
255 static int acpi_fan_speed_cmp(const void *a, const void *b)
256 {
257 	const struct acpi_fan_fps *fps1 = a;
258 	const struct acpi_fan_fps *fps2 = b;
259 	return fps1->speed - fps2->speed;
260 }
261 
262 static int acpi_fan_get_fps(struct acpi_device *device)
263 {
264 	struct acpi_fan *fan = acpi_driver_data(device);
265 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
266 	union acpi_object *obj;
267 	acpi_status status;
268 	int i;
269 
270 	status = acpi_evaluate_object(device->handle, "_FPS", NULL, &buffer);
271 	if (ACPI_FAILURE(status))
272 		return status;
273 
274 	obj = buffer.pointer;
275 	if (!obj || obj->type != ACPI_TYPE_PACKAGE || obj->package.count < 2) {
276 		dev_err(&device->dev, "Invalid _FPS data\n");
277 		status = -EINVAL;
278 		goto err;
279 	}
280 
281 	fan->fps_count = obj->package.count - 1; /* minus revision field */
282 	fan->fps = devm_kcalloc(&device->dev,
283 				fan->fps_count, sizeof(struct acpi_fan_fps),
284 				GFP_KERNEL);
285 	if (!fan->fps) {
286 		dev_err(&device->dev, "Not enough memory\n");
287 		status = -ENOMEM;
288 		goto err;
289 	}
290 	for (i = 0; i < fan->fps_count; i++) {
291 		struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
292 		struct acpi_buffer fps = { offsetof(struct acpi_fan_fps, name),
293 						&fan->fps[i] };
294 		status = acpi_extract_package(&obj->package.elements[i + 1],
295 					      &format, &fps);
296 		if (ACPI_FAILURE(status)) {
297 			dev_err(&device->dev, "Invalid _FPS element\n");
298 			goto err;
299 		}
300 	}
301 
302 	/* sort the state array according to fan speed in increase order */
303 	sort(fan->fps, fan->fps_count, sizeof(*fan->fps),
304 	     acpi_fan_speed_cmp, NULL);
305 
306 err:
307 	kfree(obj);
308 	return status;
309 }
310 
311 static int acpi_fan_probe(struct platform_device *pdev)
312 {
313 	int result = 0;
314 	struct thermal_cooling_device *cdev;
315 	struct acpi_fan *fan;
316 	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
317 	char *name;
318 
319 	if (!device)
320 		return -ENODEV;
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 
328 	fan->handle = device->handle;
329 	device->driver_data = fan;
330 	platform_set_drvdata(pdev, fan);
331 
332 	if (acpi_has_method(device->handle, "_FST")) {
333 		fan->has_fst = true;
334 		fan->acpi4 = acpi_has_method(device->handle, "_FIF") &&
335 				acpi_has_method(device->handle, "_FPS") &&
336 				acpi_has_method(device->handle, "_FSL");
337 	}
338 
339 	if (fan->acpi4) {
340 		result = acpi_fan_get_fif(device);
341 		if (result)
342 			return result;
343 
344 		result = acpi_fan_get_fps(device);
345 		if (result)
346 			return result;
347 	}
348 
349 	if (fan->has_fst) {
350 		result = devm_acpi_fan_create_hwmon(&pdev->dev);
351 		if (result)
352 			return result;
353 
354 		result = acpi_fan_create_attributes(device);
355 		if (result)
356 			return result;
357 	}
358 
359 	if (!fan->acpi4) {
360 		result = acpi_device_update_power(device, NULL);
361 		if (result) {
362 			dev_err(&device->dev, "Failed to set initial power state\n");
363 			goto err_end;
364 		}
365 	}
366 
367 	if (!strncmp(pdev->name, "PNP0C0B", strlen("PNP0C0B")))
368 		name = "Fan";
369 	else
370 		name = acpi_device_bid(device);
371 
372 	cdev = thermal_cooling_device_register(name, device,
373 						&fan_cooling_ops);
374 	if (IS_ERR(cdev)) {
375 		result = PTR_ERR(cdev);
376 		goto err_end;
377 	}
378 
379 	dev_dbg(&pdev->dev, "registered as cooling_device%d\n", cdev->id);
380 
381 	fan->cdev = cdev;
382 	result = sysfs_create_link(&pdev->dev.kobj,
383 				   &cdev->device.kobj,
384 				   "thermal_cooling");
385 	if (result) {
386 		dev_err(&pdev->dev, "Failed to create sysfs link 'thermal_cooling'\n");
387 		goto err_unregister;
388 	}
389 
390 	result = sysfs_create_link(&cdev->device.kobj,
391 				   &pdev->dev.kobj,
392 				   "device");
393 	if (result) {
394 		dev_err(&pdev->dev, "Failed to create sysfs link 'device'\n");
395 		goto err_remove_link;
396 	}
397 
398 	return 0;
399 
400 err_remove_link:
401 	sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
402 err_unregister:
403 	thermal_cooling_device_unregister(cdev);
404 err_end:
405 	if (fan->has_fst)
406 		acpi_fan_delete_attributes(device);
407 
408 	return result;
409 }
410 
411 static void acpi_fan_remove(struct platform_device *pdev)
412 {
413 	struct acpi_fan *fan = platform_get_drvdata(pdev);
414 
415 	if (fan->has_fst) {
416 		struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
417 
418 		acpi_fan_delete_attributes(device);
419 	}
420 	sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
421 	sysfs_remove_link(&fan->cdev->device.kobj, "device");
422 	thermal_cooling_device_unregister(fan->cdev);
423 }
424 
425 #ifdef CONFIG_PM_SLEEP
426 static int acpi_fan_suspend(struct device *dev)
427 {
428 	struct acpi_fan *fan = dev_get_drvdata(dev);
429 	if (fan->acpi4)
430 		return 0;
431 
432 	acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D0);
433 
434 	return AE_OK;
435 }
436 
437 static int acpi_fan_resume(struct device *dev)
438 {
439 	int result;
440 	struct acpi_fan *fan = dev_get_drvdata(dev);
441 
442 	if (fan->acpi4)
443 		return 0;
444 
445 	result = acpi_device_update_power(ACPI_COMPANION(dev), NULL);
446 	if (result)
447 		dev_err(dev, "Error updating fan power state\n");
448 
449 	return result;
450 }
451 
452 static const struct dev_pm_ops acpi_fan_pm = {
453 	.resume = acpi_fan_resume,
454 	.freeze = acpi_fan_suspend,
455 	.thaw = acpi_fan_resume,
456 	.restore = acpi_fan_resume,
457 };
458 #define FAN_PM_OPS_PTR (&acpi_fan_pm)
459 
460 #else
461 
462 #define FAN_PM_OPS_PTR NULL
463 
464 #endif
465 
466 static struct platform_driver acpi_fan_driver = {
467 	.probe = acpi_fan_probe,
468 	.remove = acpi_fan_remove,
469 	.driver = {
470 		.name = "acpi-fan",
471 		.acpi_match_table = fan_device_ids,
472 		.pm = FAN_PM_OPS_PTR,
473 	},
474 };
475 
476 module_platform_driver(acpi_fan_driver);
477 
478 MODULE_AUTHOR("Paul Diefenbaugh");
479 MODULE_DESCRIPTION("ACPI Fan Driver");
480 MODULE_LICENSE("GPL");
481