xref: /openbmc/linux/drivers/platform/x86/acerhdf.c (revision a09d2831)
1 /*
2  * acerhdf - A driver which monitors the temperature
3  *           of the aspire one netbook, turns on/off the fan
4  *           as soon as the upper/lower threshold is reached.
5  *
6  * (C) 2009 - Peter Feuerer     peter (a) piie.net
7  *                              http://piie.net
8  *     2009 Borislav Petkov <petkovbb@gmail.com>
9  *
10  * Inspired by and many thanks to:
11  *  o acerfand   - Rachel Greenham
12  *  o acer_ec.pl - Michael Kurz     michi.kurz (at) googlemail.com
13  *               - Petr Tomasek     tomasek (#) etf,cuni,cz
14  *               - Carlos Corbacho  cathectic (at) gmail.com
15  *  o lkml       - Matthew Garrett
16  *               - Borislav Petkov
17  *               - Andreas Mohr
18  *
19  *  This program is free software; you can redistribute it and/or modify
20  *  it under the terms of the GNU General Public License as published by
21  *  the Free Software Foundation; either version 2 of the License, or
22  *  (at your option) any later version.
23  *
24  *  This program is distributed in the hope that it will be useful,
25  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
26  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
27  *  GNU General Public License for more details.
28  *
29  *  You should have received a copy of the GNU General Public License
30  *  along with this program; if not, write to the Free Software
31  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
32  */
33 
34 #define pr_fmt(fmt) "acerhdf: " fmt
35 
36 #include <linux/kernel.h>
37 #include <linux/module.h>
38 #include <linux/fs.h>
39 #include <linux/dmi.h>
40 #include <acpi/acpi_drivers.h>
41 #include <linux/sched.h>
42 #include <linux/thermal.h>
43 #include <linux/platform_device.h>
44 
45 /*
46  * The driver is started with "kernel mode off" by default. That means, the BIOS
47  * is still in control of the fan. In this mode the driver allows to read the
48  * temperature of the cpu and a userspace tool may take over control of the fan.
49  * If the driver is switched to "kernel mode" (e.g. via module parameter) the
50  * driver is in full control of the fan. If you want the module to be started in
51  * kernel mode by default, define the following:
52  */
53 #undef START_IN_KERNEL_MODE
54 
55 #define DRV_VER "0.5.22"
56 
57 /*
58  * According to the Atom N270 datasheet,
59  * (http://download.intel.com/design/processor/datashts/320032.pdf) the
60  * CPU's optimal operating limits denoted in junction temperature as
61  * measured by the on-die thermal monitor are within 0 <= Tj <= 90. So,
62  * assume 89°C is critical temperature.
63  */
64 #define ACERHDF_TEMP_CRIT 89000
65 #define ACERHDF_FAN_OFF 0
66 #define ACERHDF_FAN_AUTO 1
67 
68 /*
69  * No matter what value the user puts into the fanon variable, turn on the fan
70  * at 80 degree Celsius to prevent hardware damage
71  */
72 #define ACERHDF_MAX_FANON 80000
73 
74 /*
75  * Maximum interval between two temperature checks is 15 seconds, as the die
76  * can get hot really fast under heavy load (plus we shouldn't forget about
77  * possible impact of _external_ aggressive sources such as heaters, sun etc.)
78  */
79 #define ACERHDF_MAX_INTERVAL 15
80 
81 #ifdef START_IN_KERNEL_MODE
82 static int kernelmode = 1;
83 #else
84 static int kernelmode;
85 #endif
86 
87 static unsigned int interval = 10;
88 static unsigned int fanon = 63000;
89 static unsigned int fanoff = 58000;
90 static unsigned int verbose;
91 static unsigned int fanstate = ACERHDF_FAN_AUTO;
92 static char force_bios[16];
93 static char force_product[16];
94 static unsigned int prev_interval;
95 struct thermal_zone_device *thz_dev;
96 struct thermal_cooling_device *cl_dev;
97 struct platform_device *acerhdf_dev;
98 
99 module_param(kernelmode, uint, 0);
100 MODULE_PARM_DESC(kernelmode, "Kernel mode fan control on / off");
101 module_param(interval, uint, 0600);
102 MODULE_PARM_DESC(interval, "Polling interval of temperature check");
103 module_param(fanon, uint, 0600);
104 MODULE_PARM_DESC(fanon, "Turn the fan on above this temperature");
105 module_param(fanoff, uint, 0600);
106 MODULE_PARM_DESC(fanoff, "Turn the fan off below this temperature");
107 module_param(verbose, uint, 0600);
108 MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");
109 module_param_string(force_bios, force_bios, 16, 0);
110 MODULE_PARM_DESC(force_bios, "Force BIOS version and omit BIOS check");
111 module_param_string(force_product, force_product, 16, 0);
112 MODULE_PARM_DESC(force_product, "Force BIOS product and omit BIOS check");
113 
114 /*
115  * cmd_off: to switch the fan completely off
116  * chk_off: to check if the fan is off
117  *	cmd_auto: to set the BIOS in control of the fan. The BIOS regulates then
118  *		the fan speed depending on the temperature
119  */
120 struct fancmd {
121 	u8 cmd_off;
122 	u8 chk_off;
123 	u8 cmd_auto;
124 };
125 
126 /* BIOS settings */
127 struct bios_settings_t {
128 	const char *vendor;
129 	const char *product;
130 	const char *version;
131 	unsigned char fanreg;
132 	unsigned char tempreg;
133 	struct fancmd cmd;
134 };
135 
136 /* Register addresses and values for different BIOS versions */
137 static const struct bios_settings_t bios_tbl[] = {
138 	/* AOA110 */
139 	{"Acer", "AOA110", "v0.3109", 0x55, 0x58, {0x1f, 0x1f, 0x00} },
140 	{"Acer", "AOA110", "v0.3114", 0x55, 0x58, {0x1f, 0x1f, 0x00} },
141 	{"Acer", "AOA110", "v0.3301", 0x55, 0x58, {0xaf, 0xaf, 0x00} },
142 	{"Acer", "AOA110", "v0.3304", 0x55, 0x58, {0xaf, 0xaf, 0x00} },
143 	{"Acer", "AOA110", "v0.3305", 0x55, 0x58, {0xaf, 0xaf, 0x00} },
144 	{"Acer", "AOA110", "v0.3307", 0x55, 0x58, {0xaf, 0xaf, 0x00} },
145 	{"Acer", "AOA110", "v0.3308", 0x55, 0x58, {0x21, 0x21, 0x00} },
146 	{"Acer", "AOA110", "v0.3309", 0x55, 0x58, {0x21, 0x21, 0x00} },
147 	{"Acer", "AOA110", "v0.3310", 0x55, 0x58, {0x21, 0x21, 0x00} },
148 	/* AOA150 */
149 	{"Acer", "AOA150", "v0.3114", 0x55, 0x58, {0x20, 0x20, 0x00} },
150 	{"Acer", "AOA150", "v0.3301", 0x55, 0x58, {0x20, 0x20, 0x00} },
151 	{"Acer", "AOA150", "v0.3304", 0x55, 0x58, {0x20, 0x20, 0x00} },
152 	{"Acer", "AOA150", "v0.3305", 0x55, 0x58, {0x20, 0x20, 0x00} },
153 	{"Acer", "AOA150", "v0.3307", 0x55, 0x58, {0x20, 0x20, 0x00} },
154 	{"Acer", "AOA150", "v0.3308", 0x55, 0x58, {0x20, 0x20, 0x00} },
155 	{"Acer", "AOA150", "v0.3309", 0x55, 0x58, {0x20, 0x20, 0x00} },
156 	{"Acer", "AOA150", "v0.3310", 0x55, 0x58, {0x20, 0x20, 0x00} },
157 	/* Acer 1410 */
158 	{"Acer", "Aspire 1410", "v0.3120", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
159 	{"Acer", "Aspire 1410", "v1.3303", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
160 	/* Acer 1810xx */
161 	{"Acer", "Aspire 1810TZ", "v0.3120", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
162 	{"Acer", "Aspire 1810T", "v0.3120", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
163 	{"Acer", "Aspire 1810T", "v1.3303", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
164 	{"Acer", "Aspire 1810TZ", "v1.3303", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
165 	/* Gateway */
166 	{"Gateway", "AOA110", "v0.3103", 0x55, 0x58, {0x21, 0x21, 0x00} },
167 	{"Gateway", "AOA150", "v0.3103", 0x55, 0x58, {0x20, 0x20, 0x00} },
168 	{"Gateway", "LT31", "v1.3103", 0x55, 0x58, {0x10, 0x0f, 0x00} },
169 	{"Gateway", "LT31", "v1.3201", 0x55, 0x58, {0x10, 0x0f, 0x00} },
170 	{"Gateway", "LT31", "v1.3302", 0x55, 0x58, {0x10, 0x0f, 0x00} },
171 	/* Packard Bell */
172 	{"Packard Bell", "DOA150", "v0.3104", 0x55, 0x58, {0x21, 0x21, 0x00} },
173 	{"Packard Bell", "DOA150", "v0.3105", 0x55, 0x58, {0x20, 0x20, 0x00} },
174 	{"Packard Bell", "AOA110", "v0.3105", 0x55, 0x58, {0x21, 0x21, 0x00} },
175 	{"Packard Bell", "AOA150", "v0.3105", 0x55, 0x58, {0x20, 0x20, 0x00} },
176 	{"Packard Bell", "DOTMU", "v1.3303", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
177 	{"Packard Bell", "DOTMU", "v0.3120", 0x55, 0x58, {0x9e, 0x9e, 0x00} },
178 	/* pewpew-terminator */
179 	{"", "", "", 0, 0, {0, 0, 0} }
180 };
181 
182 static const struct bios_settings_t *bios_cfg __read_mostly;
183 
184 static int acerhdf_get_temp(int *temp)
185 {
186 	u8 read_temp;
187 
188 	if (ec_read(bios_cfg->tempreg, &read_temp))
189 		return -EINVAL;
190 
191 	*temp = read_temp * 1000;
192 
193 	return 0;
194 }
195 
196 static int acerhdf_get_fanstate(int *state)
197 {
198 	u8 fan;
199 
200 	if (ec_read(bios_cfg->fanreg, &fan))
201 		return -EINVAL;
202 
203 	if (fan != bios_cfg->cmd.chk_off)
204 		*state = ACERHDF_FAN_AUTO;
205 	else
206 		*state = ACERHDF_FAN_OFF;
207 
208 	return 0;
209 }
210 
211 static void acerhdf_change_fanstate(int state)
212 {
213 	unsigned char cmd;
214 
215 	if (verbose)
216 		pr_notice("fan %s\n", (state == ACERHDF_FAN_OFF) ?
217 				"OFF" : "ON");
218 
219 	if ((state != ACERHDF_FAN_OFF) && (state != ACERHDF_FAN_AUTO)) {
220 		pr_err("invalid fan state %d requested, setting to auto!\n",
221 			state);
222 		state = ACERHDF_FAN_AUTO;
223 	}
224 
225 	cmd = (state == ACERHDF_FAN_OFF) ? bios_cfg->cmd.cmd_off
226 					 : bios_cfg->cmd.cmd_auto;
227 	fanstate = state;
228 
229 	ec_write(bios_cfg->fanreg, cmd);
230 }
231 
232 static void acerhdf_check_param(struct thermal_zone_device *thermal)
233 {
234 	if (fanon > ACERHDF_MAX_FANON) {
235 		pr_err("fanon temperature too high, set to %d\n",
236 				ACERHDF_MAX_FANON);
237 		fanon = ACERHDF_MAX_FANON;
238 	}
239 
240 	if (kernelmode && prev_interval != interval) {
241 		if (interval > ACERHDF_MAX_INTERVAL) {
242 			pr_err("interval too high, set to %d\n",
243 				ACERHDF_MAX_INTERVAL);
244 			interval = ACERHDF_MAX_INTERVAL;
245 		}
246 		if (verbose)
247 			pr_notice("interval changed to: %d\n",
248 					interval);
249 		thermal->polling_delay = interval*1000;
250 		prev_interval = interval;
251 	}
252 }
253 
254 /*
255  * This is the thermal zone callback which does the delayed polling of the fan
256  * state. We do check /sysfs-originating settings here in acerhdf_check_param()
257  * as late as the polling interval is since we can't do that in the respective
258  * accessors of the module parameters.
259  */
260 static int acerhdf_get_ec_temp(struct thermal_zone_device *thermal,
261 			       unsigned long *t)
262 {
263 	int temp, err = 0;
264 
265 	acerhdf_check_param(thermal);
266 
267 	err = acerhdf_get_temp(&temp);
268 	if (err)
269 		return err;
270 
271 	if (verbose)
272 		pr_notice("temp %d\n", temp);
273 
274 	*t = temp;
275 	return 0;
276 }
277 
278 static int acerhdf_bind(struct thermal_zone_device *thermal,
279 			struct thermal_cooling_device *cdev)
280 {
281 	/* if the cooling device is the one from acerhdf bind it */
282 	if (cdev != cl_dev)
283 		return 0;
284 
285 	if (thermal_zone_bind_cooling_device(thermal, 0, cdev)) {
286 		pr_err("error binding cooling dev\n");
287 		return -EINVAL;
288 	}
289 	return 0;
290 }
291 
292 static int acerhdf_unbind(struct thermal_zone_device *thermal,
293 			  struct thermal_cooling_device *cdev)
294 {
295 	if (cdev != cl_dev)
296 		return 0;
297 
298 	if (thermal_zone_unbind_cooling_device(thermal, 0, cdev)) {
299 		pr_err("error unbinding cooling dev\n");
300 		return -EINVAL;
301 	}
302 	return 0;
303 }
304 
305 static inline void acerhdf_revert_to_bios_mode(void)
306 {
307 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
308 	kernelmode = 0;
309 	if (thz_dev)
310 		thz_dev->polling_delay = 0;
311 	pr_notice("kernel mode fan control OFF\n");
312 }
313 static inline void acerhdf_enable_kernelmode(void)
314 {
315 	kernelmode = 1;
316 
317 	thz_dev->polling_delay = interval*1000;
318 	thermal_zone_device_update(thz_dev);
319 	pr_notice("kernel mode fan control ON\n");
320 }
321 
322 static int acerhdf_get_mode(struct thermal_zone_device *thermal,
323 			    enum thermal_device_mode *mode)
324 {
325 	if (verbose)
326 		pr_notice("kernel mode fan control %d\n", kernelmode);
327 
328 	*mode = (kernelmode) ? THERMAL_DEVICE_ENABLED
329 			     : THERMAL_DEVICE_DISABLED;
330 
331 	return 0;
332 }
333 
334 /*
335  * set operation mode;
336  * enabled: the thermal layer of the kernel takes care about
337  *          the temperature and the fan.
338  * disabled: the BIOS takes control of the fan.
339  */
340 static int acerhdf_set_mode(struct thermal_zone_device *thermal,
341 			    enum thermal_device_mode mode)
342 {
343 	if (mode == THERMAL_DEVICE_DISABLED && kernelmode)
344 		acerhdf_revert_to_bios_mode();
345 	else if (mode == THERMAL_DEVICE_ENABLED && !kernelmode)
346 		acerhdf_enable_kernelmode();
347 
348 	return 0;
349 }
350 
351 static int acerhdf_get_trip_type(struct thermal_zone_device *thermal, int trip,
352 				 enum thermal_trip_type *type)
353 {
354 	if (trip == 0)
355 		*type = THERMAL_TRIP_ACTIVE;
356 
357 	return 0;
358 }
359 
360 static int acerhdf_get_trip_temp(struct thermal_zone_device *thermal, int trip,
361 				 unsigned long *temp)
362 {
363 	if (trip == 0)
364 		*temp = fanon;
365 
366 	return 0;
367 }
368 
369 static int acerhdf_get_crit_temp(struct thermal_zone_device *thermal,
370 				 unsigned long *temperature)
371 {
372 	*temperature = ACERHDF_TEMP_CRIT;
373 	return 0;
374 }
375 
376 /* bind callback functions to thermalzone */
377 struct thermal_zone_device_ops acerhdf_dev_ops = {
378 	.bind = acerhdf_bind,
379 	.unbind = acerhdf_unbind,
380 	.get_temp = acerhdf_get_ec_temp,
381 	.get_mode = acerhdf_get_mode,
382 	.set_mode = acerhdf_set_mode,
383 	.get_trip_type = acerhdf_get_trip_type,
384 	.get_trip_temp = acerhdf_get_trip_temp,
385 	.get_crit_temp = acerhdf_get_crit_temp,
386 };
387 
388 
389 /*
390  * cooling device callback functions
391  * get maximal fan cooling state
392  */
393 static int acerhdf_get_max_state(struct thermal_cooling_device *cdev,
394 				 unsigned long *state)
395 {
396 	*state = 1;
397 
398 	return 0;
399 }
400 
401 static int acerhdf_get_cur_state(struct thermal_cooling_device *cdev,
402 				 unsigned long *state)
403 {
404 	int err = 0, tmp;
405 
406 	err = acerhdf_get_fanstate(&tmp);
407 	if (err)
408 		return err;
409 
410 	*state = (tmp == ACERHDF_FAN_AUTO) ? 1 : 0;
411 	return 0;
412 }
413 
414 /* change current fan state - is overwritten when running in kernel mode */
415 static int acerhdf_set_cur_state(struct thermal_cooling_device *cdev,
416 				 unsigned long state)
417 {
418 	int cur_temp, cur_state, err = 0;
419 
420 	if (!kernelmode)
421 		return 0;
422 
423 	err = acerhdf_get_temp(&cur_temp);
424 	if (err) {
425 		pr_err("error reading temperature, hand off control to BIOS\n");
426 		goto err_out;
427 	}
428 
429 	err = acerhdf_get_fanstate(&cur_state);
430 	if (err) {
431 		pr_err("error reading fan state, hand off control to BIOS\n");
432 		goto err_out;
433 	}
434 
435 	if (state == 0) {
436 		/* turn fan off only if below fanoff temperature */
437 		if ((cur_state == ACERHDF_FAN_AUTO) &&
438 		    (cur_temp < fanoff))
439 			acerhdf_change_fanstate(ACERHDF_FAN_OFF);
440 	} else {
441 		if (cur_state == ACERHDF_FAN_OFF)
442 			acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
443 	}
444 	return 0;
445 
446 err_out:
447 	acerhdf_revert_to_bios_mode();
448 	return -EINVAL;
449 }
450 
451 /* bind fan callbacks to fan device */
452 struct thermal_cooling_device_ops acerhdf_cooling_ops = {
453 	.get_max_state = acerhdf_get_max_state,
454 	.get_cur_state = acerhdf_get_cur_state,
455 	.set_cur_state = acerhdf_set_cur_state,
456 };
457 
458 /* suspend / resume functionality */
459 static int acerhdf_suspend(struct device *dev)
460 {
461 	if (kernelmode)
462 		acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
463 
464 	if (verbose)
465 		pr_notice("going suspend\n");
466 
467 	return 0;
468 }
469 
470 static int __devinit acerhdf_probe(struct platform_device *device)
471 {
472 	return 0;
473 }
474 
475 static int acerhdf_remove(struct platform_device *device)
476 {
477 	return 0;
478 }
479 
480 static const struct dev_pm_ops acerhdf_pm_ops = {
481 	.suspend = acerhdf_suspend,
482 	.freeze  = acerhdf_suspend,
483 };
484 
485 static struct platform_driver acerhdf_driver = {
486 	.driver = {
487 		.name  = "acerhdf",
488 		.owner = THIS_MODULE,
489 		.pm    = &acerhdf_pm_ops,
490 	},
491 	.probe = acerhdf_probe,
492 	.remove = acerhdf_remove,
493 };
494 
495 /* checks if str begins with start */
496 static int str_starts_with(const char *str, const char *start)
497 {
498 	unsigned long str_len = 0, start_len = 0;
499 
500 	str_len = strlen(str);
501 	start_len = strlen(start);
502 
503 	if (str_len >= start_len &&
504 			!strncmp(str, start, start_len))
505 		return 1;
506 
507 	return 0;
508 }
509 
510 /* check hardware */
511 static int acerhdf_check_hardware(void)
512 {
513 	char const *vendor, *version, *product;
514 	const struct bios_settings_t *bt = NULL;
515 
516 	/* get BIOS data */
517 	vendor  = dmi_get_system_info(DMI_SYS_VENDOR);
518 	version = dmi_get_system_info(DMI_BIOS_VERSION);
519 	product = dmi_get_system_info(DMI_PRODUCT_NAME);
520 
521 
522 	pr_info("Acer Aspire One Fan driver, v.%s\n", DRV_VER);
523 
524 	if (force_bios[0]) {
525 		version = force_bios;
526 		pr_info("forcing BIOS version: %s\n", version);
527 		kernelmode = 0;
528 	}
529 
530 	if (force_product[0]) {
531 		product = force_product;
532 		pr_info("forcing BIOS product: %s\n", product);
533 		kernelmode = 0;
534 	}
535 
536 	if (verbose)
537 		pr_info("BIOS info: %s %s, product: %s\n",
538 			vendor, version, product);
539 
540 	/* search BIOS version and vendor in BIOS settings table */
541 	for (bt = bios_tbl; bt->vendor[0]; bt++) {
542 		/*
543 		 * check if actual hardware BIOS vendor, product and version
544 		 * IDs start with the strings of BIOS table entry
545 		 */
546 		if (str_starts_with(vendor, bt->vendor) &&
547 				str_starts_with(product, bt->product) &&
548 				str_starts_with(version, bt->version)) {
549 			bios_cfg = bt;
550 			break;
551 		}
552 	}
553 
554 	if (!bios_cfg) {
555 		pr_err("unknown (unsupported) BIOS version %s/%s/%s, "
556 			"please report, aborting!\n", vendor, product, version);
557 		return -EINVAL;
558 	}
559 
560 	/*
561 	 * if started with kernel mode off, prevent the kernel from switching
562 	 * off the fan
563 	 */
564 	if (!kernelmode) {
565 		pr_notice("Fan control off, to enable do:\n");
566 		pr_notice("echo -n \"enabled\" > "
567 			"/sys/class/thermal/thermal_zone0/mode\n");
568 	}
569 
570 	return 0;
571 }
572 
573 static int acerhdf_register_platform(void)
574 {
575 	int err = 0;
576 
577 	err = platform_driver_register(&acerhdf_driver);
578 	if (err)
579 		return err;
580 
581 	acerhdf_dev = platform_device_alloc("acerhdf", -1);
582 	platform_device_add(acerhdf_dev);
583 
584 	return 0;
585 }
586 
587 static void acerhdf_unregister_platform(void)
588 {
589 	if (!acerhdf_dev)
590 		return;
591 
592 	platform_device_del(acerhdf_dev);
593 	platform_driver_unregister(&acerhdf_driver);
594 }
595 
596 static int acerhdf_register_thermal(void)
597 {
598 	cl_dev = thermal_cooling_device_register("acerhdf-fan", NULL,
599 						 &acerhdf_cooling_ops);
600 
601 	if (IS_ERR(cl_dev))
602 		return -EINVAL;
603 
604 	thz_dev = thermal_zone_device_register("acerhdf", 1, NULL,
605 					      &acerhdf_dev_ops, 0, 0, 0,
606 					      (kernelmode) ? interval*1000 : 0);
607 	if (IS_ERR(thz_dev))
608 		return -EINVAL;
609 
610 	return 0;
611 }
612 
613 static void acerhdf_unregister_thermal(void)
614 {
615 	if (cl_dev) {
616 		thermal_cooling_device_unregister(cl_dev);
617 		cl_dev = NULL;
618 	}
619 
620 	if (thz_dev) {
621 		thermal_zone_device_unregister(thz_dev);
622 		thz_dev = NULL;
623 	}
624 }
625 
626 static int __init acerhdf_init(void)
627 {
628 	int err = 0;
629 
630 	err = acerhdf_check_hardware();
631 	if (err)
632 		goto out_err;
633 
634 	err = acerhdf_register_platform();
635 	if (err)
636 		goto err_unreg;
637 
638 	err = acerhdf_register_thermal();
639 	if (err)
640 		goto err_unreg;
641 
642 	return 0;
643 
644 err_unreg:
645 	acerhdf_unregister_thermal();
646 	acerhdf_unregister_platform();
647 
648 out_err:
649 	return -ENODEV;
650 }
651 
652 static void __exit acerhdf_exit(void)
653 {
654 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
655 	acerhdf_unregister_thermal();
656 	acerhdf_unregister_platform();
657 }
658 
659 MODULE_LICENSE("GPL");
660 MODULE_AUTHOR("Peter Feuerer");
661 MODULE_DESCRIPTION("Aspire One temperature and fan driver");
662 MODULE_ALIAS("dmi:*:*Acer*:pnAOA*:");
663 MODULE_ALIAS("dmi:*:*Acer*:pnAspire 1410*:");
664 MODULE_ALIAS("dmi:*:*Acer*:pnAspire 1810*:");
665 MODULE_ALIAS("dmi:*:*Gateway*:pnAOA*:");
666 MODULE_ALIAS("dmi:*:*Gateway*:pnLT31*:");
667 MODULE_ALIAS("dmi:*:*Packard Bell*:pnAOA*:");
668 MODULE_ALIAS("dmi:*:*Packard Bell*:pnDOA*:");
669 MODULE_ALIAS("dmi:*:*Packard Bell*:pnDOTMU*:");
670 
671 module_init(acerhdf_init);
672 module_exit(acerhdf_exit);
673