1/*
2 *  acpi_fan.c - ACPI Fan Driver ($Revision: 29 $)
3 *
4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 *  This program is free software; you can redistribute it and/or modify
10 *  it under the terms of the GNU General Public License as published by
11 *  the Free Software Foundation; either version 2 of the License, or (at
12 *  your option) any later version.
13 *
14 *  This program is distributed in the hope that it will be useful, but
15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 *  General Public License for more details.
18 *
19 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20 */
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/init.h>
25#include <linux/types.h>
26#include <linux/uaccess.h>
27#include <linux/thermal.h>
28#include <linux/acpi.h>
29#include <linux/platform_device.h>
30#include <linux/sort.h>
31
32MODULE_AUTHOR("Paul Diefenbaugh");
33MODULE_DESCRIPTION("ACPI Fan Driver");
34MODULE_LICENSE("GPL");
35
36static int acpi_fan_probe(struct platform_device *pdev);
37static int acpi_fan_remove(struct platform_device *pdev);
38
39static const struct acpi_device_id fan_device_ids[] = {
40	{"PNP0C0B", 0},
41	{"INT3404", 0},
42	{"", 0},
43};
44MODULE_DEVICE_TABLE(acpi, fan_device_ids);
45
46#ifdef CONFIG_PM_SLEEP
47static int acpi_fan_suspend(struct device *dev);
48static int acpi_fan_resume(struct device *dev);
49static struct dev_pm_ops acpi_fan_pm = {
50	.resume = acpi_fan_resume,
51	.freeze = acpi_fan_suspend,
52	.thaw = acpi_fan_resume,
53	.restore = acpi_fan_resume,
54};
55#define FAN_PM_OPS_PTR (&acpi_fan_pm)
56#else
57#define FAN_PM_OPS_PTR NULL
58#endif
59
60struct acpi_fan_fps {
61	u64 control;
62	u64 trip_point;
63	u64 speed;
64	u64 noise_level;
65	u64 power;
66};
67
68struct acpi_fan_fif {
69	u64 revision;
70	u64 fine_grain_ctrl;
71	u64 step_size;
72	u64 low_speed_notification;
73};
74
75struct acpi_fan {
76	bool acpi4;
77	struct acpi_fan_fif fif;
78	struct acpi_fan_fps *fps;
79	int fps_count;
80	struct thermal_cooling_device *cdev;
81};
82
83static struct platform_driver acpi_fan_driver = {
84	.probe = acpi_fan_probe,
85	.remove = acpi_fan_remove,
86	.driver = {
87		.name = "acpi-fan",
88		.acpi_match_table = fan_device_ids,
89		.pm = FAN_PM_OPS_PTR,
90	},
91};
92
93/* thermal cooling device callbacks */
94static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
95			     *state)
96{
97	struct acpi_device *device = cdev->devdata;
98	struct acpi_fan *fan = acpi_driver_data(device);
99
100	if (fan->acpi4)
101		*state = fan->fps_count - 1;
102	else
103		*state = 1;
104	return 0;
105}
106
107static int fan_get_state_acpi4(struct acpi_device *device, unsigned long *state)
108{
109	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
110	struct acpi_fan *fan = acpi_driver_data(device);
111	union acpi_object *obj;
112	acpi_status status;
113	int control, i;
114
115	status = acpi_evaluate_object(device->handle, "_FST", NULL, &buffer);
116	if (ACPI_FAILURE(status)) {
117		dev_err(&device->dev, "Get fan state failed\n");
118		return status;
119	}
120
121	obj = buffer.pointer;
122	if (!obj || obj->type != ACPI_TYPE_PACKAGE ||
123	    obj->package.count != 3 ||
124	    obj->package.elements[1].type != ACPI_TYPE_INTEGER) {
125		dev_err(&device->dev, "Invalid _FST data\n");
126		status = -EINVAL;
127		goto err;
128	}
129
130	control = obj->package.elements[1].integer.value;
131	for (i = 0; i < fan->fps_count; i++) {
132		if (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		status = -EINVAL;
138		goto err;
139	}
140
141	*state = i;
142
143err:
144	kfree(obj);
145	return status;
146}
147
148static int fan_get_state(struct acpi_device *device, unsigned long *state)
149{
150	int result;
151	int acpi_state = ACPI_STATE_D0;
152
153	result = acpi_device_update_power(device, &acpi_state);
154	if (result)
155		return result;
156
157	*state = acpi_state == ACPI_STATE_D3_COLD
158			|| acpi_state == ACPI_STATE_D3_HOT ?
159		0 : (acpi_state == ACPI_STATE_D0 ? 1 : -1);
160	return 0;
161}
162
163static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
164			     *state)
165{
166	struct acpi_device *device = cdev->devdata;
167	struct acpi_fan *fan = acpi_driver_data(device);
168
169	if (fan->acpi4)
170		return fan_get_state_acpi4(device, state);
171	else
172		return fan_get_state(device, state);
173}
174
175static int fan_set_state(struct acpi_device *device, unsigned long state)
176{
177	if (state != 0 && state != 1)
178		return -EINVAL;
179
180	return acpi_device_set_power(device,
181				     state ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
182}
183
184static int fan_set_state_acpi4(struct acpi_device *device, unsigned long state)
185{
186	struct acpi_fan *fan = acpi_driver_data(device);
187	acpi_status status;
188
189	if (state >= fan->fps_count)
190		return -EINVAL;
191
192	status = acpi_execute_simple_method(device->handle, "_FSL",
193					    fan->fps[state].control);
194	if (ACPI_FAILURE(status)) {
195		dev_dbg(&device->dev, "Failed to set state by _FSL\n");
196		return status;
197	}
198
199	return 0;
200}
201
202static int
203fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
204{
205	struct acpi_device *device = cdev->devdata;
206	struct acpi_fan *fan = acpi_driver_data(device);
207
208	if (fan->acpi4)
209		return fan_set_state_acpi4(device, state);
210	else
211		return fan_set_state(device, state);
212 }
213
214static const struct thermal_cooling_device_ops fan_cooling_ops = {
215	.get_max_state = fan_get_max_state,
216	.get_cur_state = fan_get_cur_state,
217	.set_cur_state = fan_set_cur_state,
218};
219
220/* --------------------------------------------------------------------------
221 *                               Driver Interface
222 * --------------------------------------------------------------------------
223*/
224
225static bool acpi_fan_is_acpi4(struct acpi_device *device)
226{
227	return acpi_has_method(device->handle, "_FIF") &&
228	       acpi_has_method(device->handle, "_FPS") &&
229	       acpi_has_method(device->handle, "_FSL") &&
230	       acpi_has_method(device->handle, "_FST");
231}
232
233static int acpi_fan_get_fif(struct acpi_device *device)
234{
235	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
236	struct acpi_fan *fan = acpi_driver_data(device);
237	struct acpi_buffer format = { sizeof("NNNN"), "NNNN" };
238	struct acpi_buffer fif = { sizeof(fan->fif), &fan->fif };
239	union acpi_object *obj;
240	acpi_status status;
241
242	status = acpi_evaluate_object(device->handle, "_FIF", NULL, &buffer);
243	if (ACPI_FAILURE(status))
244		return status;
245
246	obj = buffer.pointer;
247	if (!obj || obj->type != ACPI_TYPE_PACKAGE) {
248		dev_err(&device->dev, "Invalid _FIF data\n");
249		status = -EINVAL;
250		goto err;
251	}
252
253	status = acpi_extract_package(obj, &format, &fif);
254	if (ACPI_FAILURE(status)) {
255		dev_err(&device->dev, "Invalid _FIF element\n");
256		status = -EINVAL;
257	}
258
259err:
260	kfree(obj);
261	return status;
262}
263
264static int acpi_fan_speed_cmp(const void *a, const void *b)
265{
266	const struct acpi_fan_fps *fps1 = a;
267	const struct acpi_fan_fps *fps2 = b;
268	return fps1->speed - fps2->speed;
269}
270
271static int acpi_fan_get_fps(struct acpi_device *device)
272{
273	struct acpi_fan *fan = acpi_driver_data(device);
274	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
275	union acpi_object *obj;
276	acpi_status status;
277	int i;
278
279	status = acpi_evaluate_object(device->handle, "_FPS", NULL, &buffer);
280	if (ACPI_FAILURE(status))
281		return status;
282
283	obj = buffer.pointer;
284	if (!obj || obj->type != ACPI_TYPE_PACKAGE || obj->package.count < 2) {
285		dev_err(&device->dev, "Invalid _FPS data\n");
286		status = -EINVAL;
287		goto err;
288	}
289
290	fan->fps_count = obj->package.count - 1; /* minus revision field */
291	fan->fps = devm_kzalloc(&device->dev,
292				fan->fps_count * sizeof(struct acpi_fan_fps),
293				GFP_KERNEL);
294	if (!fan->fps) {
295		dev_err(&device->dev, "Not enough memory\n");
296		status = -ENOMEM;
297		goto err;
298	}
299	for (i = 0; i < fan->fps_count; i++) {
300		struct acpi_buffer format = { sizeof("NNNNN"), "NNNNN" };
301		struct acpi_buffer fps = { sizeof(fan->fps[i]), &fan->fps[i] };
302		status = acpi_extract_package(&obj->package.elements[i + 1],
303					      &format, &fps);
304		if (ACPI_FAILURE(status)) {
305			dev_err(&device->dev, "Invalid _FPS element\n");
306			break;
307		}
308	}
309
310	/* sort the state array according to fan speed in increase order */
311	sort(fan->fps, fan->fps_count, sizeof(*fan->fps),
312	     acpi_fan_speed_cmp, NULL);
313
314err:
315	kfree(obj);
316	return status;
317}
318
319static int acpi_fan_probe(struct platform_device *pdev)
320{
321	int result = 0;
322	struct thermal_cooling_device *cdev;
323	struct acpi_fan *fan;
324	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
325	char *name;
326
327	fan = devm_kzalloc(&pdev->dev, sizeof(*fan), GFP_KERNEL);
328	if (!fan) {
329		dev_err(&device->dev, "No memory for fan\n");
330		return -ENOMEM;
331	}
332	device->driver_data = fan;
333	platform_set_drvdata(pdev, fan);
334
335	if (acpi_fan_is_acpi4(device)) {
336		if (acpi_fan_get_fif(device) || acpi_fan_get_fps(device))
337			goto end;
338		fan->acpi4 = true;
339	} else {
340		result = acpi_device_update_power(device, NULL);
341		if (result) {
342			dev_err(&device->dev, "Setting initial power state\n");
343			goto end;
344		}
345	}
346
347	if (!strncmp(pdev->name, "PNP0C0B", strlen("PNP0C0B")))
348		name = "Fan";
349	else
350		name = acpi_device_bid(device);
351
352	cdev = thermal_cooling_device_register(name, device,
353						&fan_cooling_ops);
354	if (IS_ERR(cdev)) {
355		result = PTR_ERR(cdev);
356		goto end;
357	}
358
359	dev_dbg(&pdev->dev, "registered as cooling_device%d\n", cdev->id);
360
361	fan->cdev = cdev;
362	result = sysfs_create_link(&pdev->dev.kobj,
363				   &cdev->device.kobj,
364				   "thermal_cooling");
365	if (result)
366		dev_err(&pdev->dev, "Failed to create sysfs link 'thermal_cooling'\n");
367
368	result = sysfs_create_link(&cdev->device.kobj,
369				   &pdev->dev.kobj,
370				   "device");
371	if (result)
372		dev_err(&pdev->dev, "Failed to create sysfs link 'device'\n");
373
374end:
375	return result;
376}
377
378static int acpi_fan_remove(struct platform_device *pdev)
379{
380	struct acpi_fan *fan = platform_get_drvdata(pdev);
381
382	sysfs_remove_link(&pdev->dev.kobj, "thermal_cooling");
383	sysfs_remove_link(&fan->cdev->device.kobj, "device");
384	thermal_cooling_device_unregister(fan->cdev);
385
386	return 0;
387}
388
389#ifdef CONFIG_PM_SLEEP
390static int acpi_fan_suspend(struct device *dev)
391{
392	struct acpi_fan *fan = dev_get_drvdata(dev);
393	if (fan->acpi4)
394		return 0;
395
396	acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D0);
397
398	return AE_OK;
399}
400
401static int acpi_fan_resume(struct device *dev)
402{
403	int result;
404	struct acpi_fan *fan = dev_get_drvdata(dev);
405
406	if (fan->acpi4)
407		return 0;
408
409	result = acpi_device_update_power(ACPI_COMPANION(dev), NULL);
410	if (result)
411		dev_err(dev, "Error updating fan power state\n");
412
413	return result;
414}
415#endif
416
417module_platform_driver(acpi_fan_driver);
418