xref: /linux/drivers/platform/x86/acerhdf.c (revision 25eb650a690b95cb0e2cf0c3b03f4900a59e0135)
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/dmi.h>
39 #include <linux/acpi.h>
40 #include <linux/thermal.h>
41 #include <linux/platform_device.h>
42 
43 /*
44  * The driver is started with "kernel mode off" by default. That means, the BIOS
45  * is still in control of the fan. In this mode the driver allows to read the
46  * temperature of the cpu and a userspace tool may take over control of the fan.
47  * If the driver is switched to "kernel mode" (e.g. via module parameter) the
48  * driver is in full control of the fan. If you want the module to be started in
49  * kernel mode by default, define the following:
50  */
51 #undef START_IN_KERNEL_MODE
52 
53 #define DRV_VER "0.5.24"
54 
55 /*
56  * According to the Atom N270 datasheet,
57  * (http://download.intel.com/design/processor/datashts/320032.pdf) the
58  * CPU's optimal operating limits denoted in junction temperature as
59  * measured by the on-die thermal monitor are within 0 <= Tj <= 90. So,
60  * assume 89°C is critical temperature.
61  */
62 #define ACERHDF_TEMP_CRIT 89000
63 #define ACERHDF_FAN_OFF 0
64 #define ACERHDF_FAN_AUTO 1
65 
66 /*
67  * No matter what value the user puts into the fanon variable, turn on the fan
68  * at 80 degree Celsius to prevent hardware damage
69  */
70 #define ACERHDF_MAX_FANON 80000
71 
72 /*
73  * Maximum interval between two temperature checks is 15 seconds, as the die
74  * can get hot really fast under heavy load (plus we shouldn't forget about
75  * possible impact of _external_ aggressive sources such as heaters, sun etc.)
76  */
77 #define ACERHDF_MAX_INTERVAL 15
78 
79 #ifdef START_IN_KERNEL_MODE
80 static int kernelmode = 1;
81 #else
82 static int kernelmode;
83 #endif
84 
85 static unsigned int interval = 10;
86 static unsigned int fanon = 63000;
87 static unsigned int fanoff = 58000;
88 static unsigned int verbose;
89 static unsigned int fanstate = ACERHDF_FAN_AUTO;
90 static char force_bios[16];
91 static char force_product[16];
92 static unsigned int prev_interval;
93 static struct thermal_zone_device *thz_dev;
94 static struct thermal_cooling_device *cl_dev;
95 static struct platform_device *acerhdf_dev;
96 
97 module_param(kernelmode, uint, 0);
98 MODULE_PARM_DESC(kernelmode, "Kernel mode fan control on / off");
99 module_param(interval, uint, 0600);
100 MODULE_PARM_DESC(interval, "Polling interval of temperature check");
101 module_param(fanon, uint, 0600);
102 MODULE_PARM_DESC(fanon, "Turn the fan on above this temperature");
103 module_param(fanoff, uint, 0600);
104 MODULE_PARM_DESC(fanoff, "Turn the fan off below this temperature");
105 module_param(verbose, uint, 0600);
106 MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");
107 module_param_string(force_bios, force_bios, 16, 0);
108 MODULE_PARM_DESC(force_bios, "Force BIOS version and omit BIOS check");
109 module_param_string(force_product, force_product, 16, 0);
110 MODULE_PARM_DESC(force_product, "Force BIOS product and omit BIOS check");
111 
112 /*
113  * cmd_off: to switch the fan completely off and check if the fan is off
114  *	cmd_auto: to set the BIOS in control of the fan. The BIOS regulates then
115  *		the fan speed depending on the temperature
116  */
117 struct fancmd {
118 	u8 cmd_off;
119 	u8 cmd_auto;
120 };
121 
122 /* BIOS settings */
123 struct bios_settings_t {
124 	const char *vendor;
125 	const char *product;
126 	const char *version;
127 	unsigned char fanreg;
128 	unsigned char tempreg;
129 	struct fancmd cmd;
130 };
131 
132 /* Register addresses and values for different BIOS versions */
133 static const struct bios_settings_t bios_tbl[] = {
134 	/* AOA110 */
135 	{"Acer", "AOA110", "v0.3109", 0x55, 0x58, {0x1f, 0x00} },
136 	{"Acer", "AOA110", "v0.3114", 0x55, 0x58, {0x1f, 0x00} },
137 	{"Acer", "AOA110", "v0.3301", 0x55, 0x58, {0xaf, 0x00} },
138 	{"Acer", "AOA110", "v0.3304", 0x55, 0x58, {0xaf, 0x00} },
139 	{"Acer", "AOA110", "v0.3305", 0x55, 0x58, {0xaf, 0x00} },
140 	{"Acer", "AOA110", "v0.3307", 0x55, 0x58, {0xaf, 0x00} },
141 	{"Acer", "AOA110", "v0.3308", 0x55, 0x58, {0x21, 0x00} },
142 	{"Acer", "AOA110", "v0.3309", 0x55, 0x58, {0x21, 0x00} },
143 	{"Acer", "AOA110", "v0.3310", 0x55, 0x58, {0x21, 0x00} },
144 	/* AOA150 */
145 	{"Acer", "AOA150", "v0.3114", 0x55, 0x58, {0x1f, 0x00} },
146 	{"Acer", "AOA150", "v0.3301", 0x55, 0x58, {0x20, 0x00} },
147 	{"Acer", "AOA150", "v0.3304", 0x55, 0x58, {0x20, 0x00} },
148 	{"Acer", "AOA150", "v0.3305", 0x55, 0x58, {0x20, 0x00} },
149 	{"Acer", "AOA150", "v0.3307", 0x55, 0x58, {0x20, 0x00} },
150 	{"Acer", "AOA150", "v0.3308", 0x55, 0x58, {0x20, 0x00} },
151 	{"Acer", "AOA150", "v0.3309", 0x55, 0x58, {0x20, 0x00} },
152 	{"Acer", "AOA150", "v0.3310", 0x55, 0x58, {0x20, 0x00} },
153 	/* Acer 1410 */
154 	{"Acer", "Aspire 1410", "v0.3108", 0x55, 0x58, {0x9e, 0x00} },
155 	{"Acer", "Aspire 1410", "v0.3113", 0x55, 0x58, {0x9e, 0x00} },
156 	{"Acer", "Aspire 1410", "v0.3115", 0x55, 0x58, {0x9e, 0x00} },
157 	{"Acer", "Aspire 1410", "v0.3117", 0x55, 0x58, {0x9e, 0x00} },
158 	{"Acer", "Aspire 1410", "v0.3119", 0x55, 0x58, {0x9e, 0x00} },
159 	{"Acer", "Aspire 1410", "v0.3120", 0x55, 0x58, {0x9e, 0x00} },
160 	{"Acer", "Aspire 1410", "v1.3204", 0x55, 0x58, {0x9e, 0x00} },
161 	{"Acer", "Aspire 1410", "v1.3303", 0x55, 0x58, {0x9e, 0x00} },
162 	{"Acer", "Aspire 1410", "v1.3308", 0x55, 0x58, {0x9e, 0x00} },
163 	{"Acer", "Aspire 1410", "v1.3310", 0x55, 0x58, {0x9e, 0x00} },
164 	/* Acer 1810xx */
165 	{"Acer", "Aspire 1810TZ", "v0.3108", 0x55, 0x58, {0x9e, 0x00} },
166 	{"Acer", "Aspire 1810T",  "v0.3108", 0x55, 0x58, {0x9e, 0x00} },
167 	{"Acer", "Aspire 1810TZ", "v0.3113", 0x55, 0x58, {0x9e, 0x00} },
168 	{"Acer", "Aspire 1810T",  "v0.3113", 0x55, 0x58, {0x9e, 0x00} },
169 	{"Acer", "Aspire 1810TZ", "v0.3115", 0x55, 0x58, {0x9e, 0x00} },
170 	{"Acer", "Aspire 1810T",  "v0.3115", 0x55, 0x58, {0x9e, 0x00} },
171 	{"Acer", "Aspire 1810TZ", "v0.3117", 0x55, 0x58, {0x9e, 0x00} },
172 	{"Acer", "Aspire 1810T",  "v0.3117", 0x55, 0x58, {0x9e, 0x00} },
173 	{"Acer", "Aspire 1810TZ", "v0.3119", 0x55, 0x58, {0x9e, 0x00} },
174 	{"Acer", "Aspire 1810T",  "v0.3119", 0x55, 0x58, {0x9e, 0x00} },
175 	{"Acer", "Aspire 1810TZ", "v0.3120", 0x55, 0x58, {0x9e, 0x00} },
176 	{"Acer", "Aspire 1810T",  "v0.3120", 0x55, 0x58, {0x9e, 0x00} },
177 	{"Acer", "Aspire 1810TZ", "v1.3204", 0x55, 0x58, {0x9e, 0x00} },
178 	{"Acer", "Aspire 1810T",  "v1.3204", 0x55, 0x58, {0x9e, 0x00} },
179 	{"Acer", "Aspire 1810TZ", "v1.3303", 0x55, 0x58, {0x9e, 0x00} },
180 	{"Acer", "Aspire 1810T",  "v1.3303", 0x55, 0x58, {0x9e, 0x00} },
181 	{"Acer", "Aspire 1810TZ", "v1.3308", 0x55, 0x58, {0x9e, 0x00} },
182 	{"Acer", "Aspire 1810T",  "v1.3308", 0x55, 0x58, {0x9e, 0x00} },
183 	{"Acer", "Aspire 1810TZ", "v1.3310", 0x55, 0x58, {0x9e, 0x00} },
184 	{"Acer", "Aspire 1810T",  "v1.3310", 0x55, 0x58, {0x9e, 0x00} },
185 	/* Acer 531 */
186 	{"Acer", "AO531h", "v0.3201", 0x55, 0x58, {0x20, 0x00} },
187 	/* Gateway */
188 	{"Gateway", "AOA110", "v0.3103", 0x55, 0x58, {0x21, 0x00} },
189 	{"Gateway", "AOA150", "v0.3103", 0x55, 0x58, {0x20, 0x00} },
190 	{"Gateway", "LT31",   "v1.3103", 0x55, 0x58, {0x9e, 0x00} },
191 	{"Gateway", "LT31",   "v1.3201", 0x55, 0x58, {0x9e, 0x00} },
192 	{"Gateway", "LT31",   "v1.3302", 0x55, 0x58, {0x9e, 0x00} },
193 	/* Packard Bell */
194 	{"Packard Bell", "DOA150", "v0.3104", 0x55, 0x58, {0x21, 0x00} },
195 	{"Packard Bell", "DOA150", "v0.3105", 0x55, 0x58, {0x20, 0x00} },
196 	{"Packard Bell", "AOA110", "v0.3105", 0x55, 0x58, {0x21, 0x00} },
197 	{"Packard Bell", "AOA150", "v0.3105", 0x55, 0x58, {0x20, 0x00} },
198 	{"Packard Bell", "DOTMU",  "v1.3303", 0x55, 0x58, {0x9e, 0x00} },
199 	{"Packard Bell", "DOTMU",  "v0.3120", 0x55, 0x58, {0x9e, 0x00} },
200 	{"Packard Bell", "DOTMU",  "v0.3108", 0x55, 0x58, {0x9e, 0x00} },
201 	{"Packard Bell", "DOTMU",  "v0.3113", 0x55, 0x58, {0x9e, 0x00} },
202 	{"Packard Bell", "DOTMU",  "v0.3115", 0x55, 0x58, {0x9e, 0x00} },
203 	{"Packard Bell", "DOTMU",  "v0.3117", 0x55, 0x58, {0x9e, 0x00} },
204 	{"Packard Bell", "DOTMU",  "v0.3119", 0x55, 0x58, {0x9e, 0x00} },
205 	{"Packard Bell", "DOTMU",  "v1.3204", 0x55, 0x58, {0x9e, 0x00} },
206 	{"Packard Bell", "DOTMA",  "v1.3201", 0x55, 0x58, {0x9e, 0x00} },
207 	{"Packard Bell", "DOTMA",  "v1.3302", 0x55, 0x58, {0x9e, 0x00} },
208 	/* pewpew-terminator */
209 	{"", "", "", 0, 0, {0, 0} }
210 };
211 
212 static const struct bios_settings_t *bios_cfg __read_mostly;
213 
214 static int acerhdf_get_temp(int *temp)
215 {
216 	u8 read_temp;
217 
218 	if (ec_read(bios_cfg->tempreg, &read_temp))
219 		return -EINVAL;
220 
221 	*temp = read_temp * 1000;
222 
223 	return 0;
224 }
225 
226 static int acerhdf_get_fanstate(int *state)
227 {
228 	u8 fan;
229 
230 	if (ec_read(bios_cfg->fanreg, &fan))
231 		return -EINVAL;
232 
233 	if (fan != bios_cfg->cmd.cmd_off)
234 		*state = ACERHDF_FAN_AUTO;
235 	else
236 		*state = ACERHDF_FAN_OFF;
237 
238 	return 0;
239 }
240 
241 static void acerhdf_change_fanstate(int state)
242 {
243 	unsigned char cmd;
244 
245 	if (verbose)
246 		pr_notice("fan %s\n", (state == ACERHDF_FAN_OFF) ?
247 				"OFF" : "ON");
248 
249 	if ((state != ACERHDF_FAN_OFF) && (state != ACERHDF_FAN_AUTO)) {
250 		pr_err("invalid fan state %d requested, setting to auto!\n",
251 			state);
252 		state = ACERHDF_FAN_AUTO;
253 	}
254 
255 	cmd = (state == ACERHDF_FAN_OFF) ? bios_cfg->cmd.cmd_off
256 					 : bios_cfg->cmd.cmd_auto;
257 	fanstate = state;
258 
259 	ec_write(bios_cfg->fanreg, cmd);
260 }
261 
262 static void acerhdf_check_param(struct thermal_zone_device *thermal)
263 {
264 	if (fanon > ACERHDF_MAX_FANON) {
265 		pr_err("fanon temperature too high, set to %d\n",
266 				ACERHDF_MAX_FANON);
267 		fanon = ACERHDF_MAX_FANON;
268 	}
269 
270 	if (kernelmode && prev_interval != interval) {
271 		if (interval > ACERHDF_MAX_INTERVAL) {
272 			pr_err("interval too high, set to %d\n",
273 				ACERHDF_MAX_INTERVAL);
274 			interval = ACERHDF_MAX_INTERVAL;
275 		}
276 		if (verbose)
277 			pr_notice("interval changed to: %d\n",
278 					interval);
279 		thermal->polling_delay = interval*1000;
280 		prev_interval = interval;
281 	}
282 }
283 
284 /*
285  * This is the thermal zone callback which does the delayed polling of the fan
286  * state. We do check /sysfs-originating settings here in acerhdf_check_param()
287  * as late as the polling interval is since we can't do that in the respective
288  * accessors of the module parameters.
289  */
290 static int acerhdf_get_ec_temp(struct thermal_zone_device *thermal,
291 			       unsigned long *t)
292 {
293 	int temp, err = 0;
294 
295 	acerhdf_check_param(thermal);
296 
297 	err = acerhdf_get_temp(&temp);
298 	if (err)
299 		return err;
300 
301 	if (verbose)
302 		pr_notice("temp %d\n", temp);
303 
304 	*t = temp;
305 	return 0;
306 }
307 
308 static int acerhdf_bind(struct thermal_zone_device *thermal,
309 			struct thermal_cooling_device *cdev)
310 {
311 	/* if the cooling device is the one from acerhdf bind it */
312 	if (cdev != cl_dev)
313 		return 0;
314 
315 	if (thermal_zone_bind_cooling_device(thermal, 0, cdev)) {
316 		pr_err("error binding cooling dev\n");
317 		return -EINVAL;
318 	}
319 	return 0;
320 }
321 
322 static int acerhdf_unbind(struct thermal_zone_device *thermal,
323 			  struct thermal_cooling_device *cdev)
324 {
325 	if (cdev != cl_dev)
326 		return 0;
327 
328 	if (thermal_zone_unbind_cooling_device(thermal, 0, cdev)) {
329 		pr_err("error unbinding cooling dev\n");
330 		return -EINVAL;
331 	}
332 	return 0;
333 }
334 
335 static inline void acerhdf_revert_to_bios_mode(void)
336 {
337 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
338 	kernelmode = 0;
339 	if (thz_dev)
340 		thz_dev->polling_delay = 0;
341 	pr_notice("kernel mode fan control OFF\n");
342 }
343 static inline void acerhdf_enable_kernelmode(void)
344 {
345 	kernelmode = 1;
346 
347 	thz_dev->polling_delay = interval*1000;
348 	thermal_zone_device_update(thz_dev);
349 	pr_notice("kernel mode fan control ON\n");
350 }
351 
352 static int acerhdf_get_mode(struct thermal_zone_device *thermal,
353 			    enum thermal_device_mode *mode)
354 {
355 	if (verbose)
356 		pr_notice("kernel mode fan control %d\n", kernelmode);
357 
358 	*mode = (kernelmode) ? THERMAL_DEVICE_ENABLED
359 			     : THERMAL_DEVICE_DISABLED;
360 
361 	return 0;
362 }
363 
364 /*
365  * set operation mode;
366  * enabled: the thermal layer of the kernel takes care about
367  *          the temperature and the fan.
368  * disabled: the BIOS takes control of the fan.
369  */
370 static int acerhdf_set_mode(struct thermal_zone_device *thermal,
371 			    enum thermal_device_mode mode)
372 {
373 	if (mode == THERMAL_DEVICE_DISABLED && kernelmode)
374 		acerhdf_revert_to_bios_mode();
375 	else if (mode == THERMAL_DEVICE_ENABLED && !kernelmode)
376 		acerhdf_enable_kernelmode();
377 
378 	return 0;
379 }
380 
381 static int acerhdf_get_trip_type(struct thermal_zone_device *thermal, int trip,
382 				 enum thermal_trip_type *type)
383 {
384 	if (trip == 0)
385 		*type = THERMAL_TRIP_ACTIVE;
386 
387 	return 0;
388 }
389 
390 static int acerhdf_get_trip_temp(struct thermal_zone_device *thermal, int trip,
391 				 unsigned long *temp)
392 {
393 	if (trip == 0)
394 		*temp = fanon;
395 
396 	return 0;
397 }
398 
399 static int acerhdf_get_crit_temp(struct thermal_zone_device *thermal,
400 				 unsigned long *temperature)
401 {
402 	*temperature = ACERHDF_TEMP_CRIT;
403 	return 0;
404 }
405 
406 /* bind callback functions to thermalzone */
407 static struct thermal_zone_device_ops acerhdf_dev_ops = {
408 	.bind = acerhdf_bind,
409 	.unbind = acerhdf_unbind,
410 	.get_temp = acerhdf_get_ec_temp,
411 	.get_mode = acerhdf_get_mode,
412 	.set_mode = acerhdf_set_mode,
413 	.get_trip_type = acerhdf_get_trip_type,
414 	.get_trip_temp = acerhdf_get_trip_temp,
415 	.get_crit_temp = acerhdf_get_crit_temp,
416 };
417 
418 
419 /*
420  * cooling device callback functions
421  * get maximal fan cooling state
422  */
423 static int acerhdf_get_max_state(struct thermal_cooling_device *cdev,
424 				 unsigned long *state)
425 {
426 	*state = 1;
427 
428 	return 0;
429 }
430 
431 static int acerhdf_get_cur_state(struct thermal_cooling_device *cdev,
432 				 unsigned long *state)
433 {
434 	int err = 0, tmp;
435 
436 	err = acerhdf_get_fanstate(&tmp);
437 	if (err)
438 		return err;
439 
440 	*state = (tmp == ACERHDF_FAN_AUTO) ? 1 : 0;
441 	return 0;
442 }
443 
444 /* change current fan state - is overwritten when running in kernel mode */
445 static int acerhdf_set_cur_state(struct thermal_cooling_device *cdev,
446 				 unsigned long state)
447 {
448 	int cur_temp, cur_state, err = 0;
449 
450 	if (!kernelmode)
451 		return 0;
452 
453 	err = acerhdf_get_temp(&cur_temp);
454 	if (err) {
455 		pr_err("error reading temperature, hand off control to BIOS\n");
456 		goto err_out;
457 	}
458 
459 	err = acerhdf_get_fanstate(&cur_state);
460 	if (err) {
461 		pr_err("error reading fan state, hand off control to BIOS\n");
462 		goto err_out;
463 	}
464 
465 	if (state == 0) {
466 		/* turn fan off only if below fanoff temperature */
467 		if ((cur_state == ACERHDF_FAN_AUTO) &&
468 		    (cur_temp < fanoff))
469 			acerhdf_change_fanstate(ACERHDF_FAN_OFF);
470 	} else {
471 		if (cur_state == ACERHDF_FAN_OFF)
472 			acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
473 	}
474 	return 0;
475 
476 err_out:
477 	acerhdf_revert_to_bios_mode();
478 	return -EINVAL;
479 }
480 
481 /* bind fan callbacks to fan device */
482 static struct thermal_cooling_device_ops acerhdf_cooling_ops = {
483 	.get_max_state = acerhdf_get_max_state,
484 	.get_cur_state = acerhdf_get_cur_state,
485 	.set_cur_state = acerhdf_set_cur_state,
486 };
487 
488 /* suspend / resume functionality */
489 static int acerhdf_suspend(struct device *dev)
490 {
491 	if (kernelmode)
492 		acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
493 
494 	if (verbose)
495 		pr_notice("going suspend\n");
496 
497 	return 0;
498 }
499 
500 static int __devinit acerhdf_probe(struct platform_device *device)
501 {
502 	return 0;
503 }
504 
505 static int acerhdf_remove(struct platform_device *device)
506 {
507 	return 0;
508 }
509 
510 static const struct dev_pm_ops acerhdf_pm_ops = {
511 	.suspend = acerhdf_suspend,
512 	.freeze  = acerhdf_suspend,
513 };
514 
515 static struct platform_driver acerhdf_driver = {
516 	.driver = {
517 		.name  = "acerhdf",
518 		.owner = THIS_MODULE,
519 		.pm    = &acerhdf_pm_ops,
520 	},
521 	.probe = acerhdf_probe,
522 	.remove = acerhdf_remove,
523 };
524 
525 /* checks if str begins with start */
526 static int str_starts_with(const char *str, const char *start)
527 {
528 	unsigned long str_len = 0, start_len = 0;
529 
530 	str_len = strlen(str);
531 	start_len = strlen(start);
532 
533 	if (str_len >= start_len &&
534 			!strncmp(str, start, start_len))
535 		return 1;
536 
537 	return 0;
538 }
539 
540 /* check hardware */
541 static int acerhdf_check_hardware(void)
542 {
543 	char const *vendor, *version, *product;
544 	const struct bios_settings_t *bt = NULL;
545 
546 	/* get BIOS data */
547 	vendor  = dmi_get_system_info(DMI_SYS_VENDOR);
548 	version = dmi_get_system_info(DMI_BIOS_VERSION);
549 	product = dmi_get_system_info(DMI_PRODUCT_NAME);
550 
551 	if (!vendor || !version || !product) {
552 		pr_err("error getting hardware information\n");
553 		return -EINVAL;
554 	}
555 
556 	pr_info("Acer Aspire One Fan driver, v.%s\n", DRV_VER);
557 
558 	if (force_bios[0]) {
559 		version = force_bios;
560 		pr_info("forcing BIOS version: %s\n", version);
561 		kernelmode = 0;
562 	}
563 
564 	if (force_product[0]) {
565 		product = force_product;
566 		pr_info("forcing BIOS product: %s\n", product);
567 		kernelmode = 0;
568 	}
569 
570 	if (verbose)
571 		pr_info("BIOS info: %s %s, product: %s\n",
572 			vendor, version, product);
573 
574 	/* search BIOS version and vendor in BIOS settings table */
575 	for (bt = bios_tbl; bt->vendor[0]; bt++) {
576 		/*
577 		 * check if actual hardware BIOS vendor, product and version
578 		 * IDs start with the strings of BIOS table entry
579 		 */
580 		if (str_starts_with(vendor, bt->vendor) &&
581 				str_starts_with(product, bt->product) &&
582 				str_starts_with(version, bt->version)) {
583 			bios_cfg = bt;
584 			break;
585 		}
586 	}
587 
588 	if (!bios_cfg) {
589 		pr_err("unknown (unsupported) BIOS version %s/%s/%s, "
590 			"please report, aborting!\n", vendor, product, version);
591 		return -EINVAL;
592 	}
593 
594 	/*
595 	 * if started with kernel mode off, prevent the kernel from switching
596 	 * off the fan
597 	 */
598 	if (!kernelmode) {
599 		pr_notice("Fan control off, to enable do:\n");
600 		pr_notice("echo -n \"enabled\" > "
601 			"/sys/class/thermal/thermal_zone0/mode\n");
602 	}
603 
604 	return 0;
605 }
606 
607 static int acerhdf_register_platform(void)
608 {
609 	int err = 0;
610 
611 	err = platform_driver_register(&acerhdf_driver);
612 	if (err)
613 		return err;
614 
615 	acerhdf_dev = platform_device_alloc("acerhdf", -1);
616 	if (!acerhdf_dev) {
617 		err = -ENOMEM;
618 		goto err_device_alloc;
619 	}
620 	err = platform_device_add(acerhdf_dev);
621 	if (err)
622 		goto err_device_add;
623 
624 	return 0;
625 
626 err_device_add:
627 	platform_device_put(acerhdf_dev);
628 err_device_alloc:
629 	platform_driver_unregister(&acerhdf_driver);
630 	return err;
631 }
632 
633 static void acerhdf_unregister_platform(void)
634 {
635 	platform_device_unregister(acerhdf_dev);
636 	platform_driver_unregister(&acerhdf_driver);
637 }
638 
639 static int acerhdf_register_thermal(void)
640 {
641 	cl_dev = thermal_cooling_device_register("acerhdf-fan", NULL,
642 						 &acerhdf_cooling_ops);
643 
644 	if (IS_ERR(cl_dev))
645 		return -EINVAL;
646 
647 	thz_dev = thermal_zone_device_register("acerhdf", 1, NULL,
648 					      &acerhdf_dev_ops, 0, 0, 0,
649 					      (kernelmode) ? interval*1000 : 0);
650 	if (IS_ERR(thz_dev))
651 		return -EINVAL;
652 
653 	return 0;
654 }
655 
656 static void acerhdf_unregister_thermal(void)
657 {
658 	if (cl_dev) {
659 		thermal_cooling_device_unregister(cl_dev);
660 		cl_dev = NULL;
661 	}
662 
663 	if (thz_dev) {
664 		thermal_zone_device_unregister(thz_dev);
665 		thz_dev = NULL;
666 	}
667 }
668 
669 static int __init acerhdf_init(void)
670 {
671 	int err = 0;
672 
673 	err = acerhdf_check_hardware();
674 	if (err)
675 		goto out_err;
676 
677 	err = acerhdf_register_platform();
678 	if (err)
679 		goto out_err;
680 
681 	err = acerhdf_register_thermal();
682 	if (err)
683 		goto err_unreg;
684 
685 	return 0;
686 
687 err_unreg:
688 	acerhdf_unregister_thermal();
689 	acerhdf_unregister_platform();
690 
691 out_err:
692 	return err;
693 }
694 
695 static void __exit acerhdf_exit(void)
696 {
697 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
698 	acerhdf_unregister_thermal();
699 	acerhdf_unregister_platform();
700 }
701 
702 MODULE_LICENSE("GPL");
703 MODULE_AUTHOR("Peter Feuerer");
704 MODULE_DESCRIPTION("Aspire One temperature and fan driver");
705 MODULE_ALIAS("dmi:*:*Acer*:pnAOA*:");
706 MODULE_ALIAS("dmi:*:*Acer*:pnAspire 1410*:");
707 MODULE_ALIAS("dmi:*:*Acer*:pnAspire 1810*:");
708 MODULE_ALIAS("dmi:*:*Acer*:pnAO531*:");
709 MODULE_ALIAS("dmi:*:*Gateway*:pnAOA*:");
710 MODULE_ALIAS("dmi:*:*Gateway*:pnLT31*:");
711 MODULE_ALIAS("dmi:*:*Packard Bell*:pnAOA*:");
712 MODULE_ALIAS("dmi:*:*Packard Bell*:pnDOA*:");
713 MODULE_ALIAS("dmi:*:*Packard Bell*:pnDOTMU*:");
714 MODULE_ALIAS("dmi:*:*Packard Bell*:pnDOTMA*:");
715 
716 module_init(acerhdf_init);
717 module_exit(acerhdf_exit);
718