xref: /linux/drivers/platform/x86/acerhdf.c (revision 27258e448eb301cf89e351df87aa8cb916653bf2)
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 "0.5.13"
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 89
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 80
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 = 63;
89 static unsigned int fanoff = 58;
90 static unsigned int verbose;
91 static unsigned int fanstate = ACERHDF_FAN_AUTO;
92 static char force_bios[16];
93 static unsigned int prev_interval;
94 struct thermal_zone_device *thz_dev;
95 struct thermal_cooling_device *cl_dev;
96 struct platform_device *acerhdf_dev;
97 
98 module_param(kernelmode, uint, 0);
99 MODULE_PARM_DESC(kernelmode, "Kernel mode fan control on / off");
100 module_param(interval, uint, 0600);
101 MODULE_PARM_DESC(interval, "Polling interval of temperature check");
102 module_param(fanon, uint, 0600);
103 MODULE_PARM_DESC(fanon, "Turn the fan on above this temperature");
104 module_param(fanoff, uint, 0600);
105 MODULE_PARM_DESC(fanoff, "Turn the fan off below this temperature");
106 module_param(verbose, uint, 0600);
107 MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");
108 module_param_string(force_bios, force_bios, 16, 0);
109 MODULE_PARM_DESC(force_bios, "Force BIOS version and omit BIOS check");
110 
111 /* BIOS settings */
112 struct bios_settings_t {
113 	const char *vendor;
114 	const char *version;
115 	unsigned char fanreg;
116 	unsigned char tempreg;
117 	unsigned char fancmd[2]; /* fan off and auto commands */
118 };
119 
120 /* Register addresses and values for different BIOS versions */
121 static const struct bios_settings_t bios_tbl[] = {
122 	{"Acer", "v0.3109", 0x55, 0x58, {0x1f, 0x00} },
123 	{"Acer", "v0.3114", 0x55, 0x58, {0x1f, 0x00} },
124 	{"Acer", "v0.3301", 0x55, 0x58, {0xaf, 0x00} },
125 	{"Acer", "v0.3304", 0x55, 0x58, {0xaf, 0x00} },
126 	{"Acer", "v0.3305", 0x55, 0x58, {0xaf, 0x00} },
127 	{"Acer", "v0.3308", 0x55, 0x58, {0x21, 0x00} },
128 	{"Acer", "v0.3309", 0x55, 0x58, {0x21, 0x00} },
129 	{"Acer", "v0.3310", 0x55, 0x58, {0x21, 0x00} },
130 	{"Gateway", "v0.3103", 0x55, 0x58, {0x21, 0x00} },
131 	{"Packard Bell", "v0.3105", 0x55, 0x58, {0x21, 0x00} },
132 	{"", "", 0, 0, {0, 0} }
133 };
134 
135 static const struct bios_settings_t *bios_cfg __read_mostly;
136 
137 
138 static int acerhdf_get_temp(int *temp)
139 {
140 	u8 read_temp;
141 
142 	if (ec_read(bios_cfg->tempreg, &read_temp))
143 		return -EINVAL;
144 
145 	*temp = read_temp;
146 
147 	return 0;
148 }
149 
150 static int acerhdf_get_fanstate(int *state)
151 {
152 	u8 fan;
153 	bool tmp;
154 
155 	if (ec_read(bios_cfg->fanreg, &fan))
156 		return -EINVAL;
157 
158 	tmp = (fan == bios_cfg->fancmd[ACERHDF_FAN_OFF]);
159 	*state = tmp ? ACERHDF_FAN_OFF : ACERHDF_FAN_AUTO;
160 
161 	return 0;
162 }
163 
164 static void acerhdf_change_fanstate(int state)
165 {
166 	unsigned char cmd;
167 
168 	if (verbose)
169 		pr_notice("fan %s\n", (state == ACERHDF_FAN_OFF) ?
170 				"OFF" : "ON");
171 
172 	if ((state != ACERHDF_FAN_OFF) && (state != ACERHDF_FAN_AUTO)) {
173 		pr_err("invalid fan state %d requested, setting to auto!\n",
174 			state);
175 		state = ACERHDF_FAN_AUTO;
176 	}
177 
178 	cmd = bios_cfg->fancmd[state];
179 	fanstate = state;
180 
181 	ec_write(bios_cfg->fanreg, cmd);
182 }
183 
184 static void acerhdf_check_param(struct thermal_zone_device *thermal)
185 {
186 	if (fanon > ACERHDF_MAX_FANON) {
187 		pr_err("fanon temperature too high, set to %d\n",
188 				ACERHDF_MAX_FANON);
189 		fanon = ACERHDF_MAX_FANON;
190 	}
191 
192 	if (kernelmode && prev_interval != interval) {
193 		if (interval > ACERHDF_MAX_INTERVAL) {
194 			pr_err("interval too high, set to %d\n",
195 				ACERHDF_MAX_INTERVAL);
196 			interval = ACERHDF_MAX_INTERVAL;
197 		}
198 		if (verbose)
199 			pr_notice("interval changed to: %d\n",
200 					interval);
201 		thermal->polling_delay = interval*1000;
202 		prev_interval = interval;
203 	}
204 }
205 
206 /*
207  * This is the thermal zone callback which does the delayed polling of the fan
208  * state. We do check /sysfs-originating settings here in acerhdf_check_param()
209  * as late as the polling interval is since we can't do that in the respective
210  * accessors of the module parameters.
211  */
212 static int acerhdf_get_ec_temp(struct thermal_zone_device *thermal,
213 			       unsigned long *t)
214 {
215 	int temp, err = 0;
216 
217 	acerhdf_check_param(thermal);
218 
219 	err = acerhdf_get_temp(&temp);
220 	if (err)
221 		return err;
222 
223 	if (verbose)
224 		pr_notice("temp %d\n", temp);
225 
226 	*t = temp;
227 	return 0;
228 }
229 
230 static int acerhdf_bind(struct thermal_zone_device *thermal,
231 			struct thermal_cooling_device *cdev)
232 {
233 	/* if the cooling device is the one from acerhdf bind it */
234 	if (cdev != cl_dev)
235 		return 0;
236 
237 	if (thermal_zone_bind_cooling_device(thermal, 0, cdev)) {
238 		pr_err("error binding cooling dev\n");
239 		return -EINVAL;
240 	}
241 	return 0;
242 }
243 
244 static int acerhdf_unbind(struct thermal_zone_device *thermal,
245 			  struct thermal_cooling_device *cdev)
246 {
247 	if (cdev != cl_dev)
248 		return 0;
249 
250 	if (thermal_zone_unbind_cooling_device(thermal, 0, cdev)) {
251 		pr_err("error unbinding cooling dev\n");
252 		return -EINVAL;
253 	}
254 	return 0;
255 }
256 
257 static inline void acerhdf_revert_to_bios_mode(void)
258 {
259 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
260 	kernelmode = 0;
261 	if (thz_dev)
262 		thz_dev->polling_delay = 0;
263 	pr_notice("kernel mode fan control OFF\n");
264 }
265 static inline void acerhdf_enable_kernelmode(void)
266 {
267 	kernelmode = 1;
268 
269 	thz_dev->polling_delay = interval*1000;
270 	thermal_zone_device_update(thz_dev);
271 	pr_notice("kernel mode fan control ON\n");
272 }
273 
274 static int acerhdf_get_mode(struct thermal_zone_device *thermal,
275 			    enum thermal_device_mode *mode)
276 {
277 	if (verbose)
278 		pr_notice("kernel mode fan control %d\n", kernelmode);
279 
280 	*mode = (kernelmode) ? THERMAL_DEVICE_ENABLED
281 			     : THERMAL_DEVICE_DISABLED;
282 
283 	return 0;
284 }
285 
286 /*
287  * set operation mode;
288  * enabled: the thermal layer of the kernel takes care about
289  *          the temperature and the fan.
290  * disabled: the BIOS takes control of the fan.
291  */
292 static int acerhdf_set_mode(struct thermal_zone_device *thermal,
293 			    enum thermal_device_mode mode)
294 {
295 	if (mode == THERMAL_DEVICE_DISABLED && kernelmode)
296 		acerhdf_revert_to_bios_mode();
297 	else if (mode == THERMAL_DEVICE_ENABLED && !kernelmode)
298 		acerhdf_enable_kernelmode();
299 
300 	return 0;
301 }
302 
303 static int acerhdf_get_trip_type(struct thermal_zone_device *thermal, int trip,
304 				 enum thermal_trip_type *type)
305 {
306 	if (trip == 0)
307 		*type = THERMAL_TRIP_ACTIVE;
308 
309 	return 0;
310 }
311 
312 static int acerhdf_get_trip_temp(struct thermal_zone_device *thermal, int trip,
313 				 unsigned long *temp)
314 {
315 	if (trip == 0)
316 		*temp = fanon;
317 
318 	return 0;
319 }
320 
321 static int acerhdf_get_crit_temp(struct thermal_zone_device *thermal,
322 				 unsigned long *temperature)
323 {
324 	*temperature = ACERHDF_TEMP_CRIT;
325 	return 0;
326 }
327 
328 /* bind callback functions to thermalzone */
329 struct thermal_zone_device_ops acerhdf_dev_ops = {
330 	.bind = acerhdf_bind,
331 	.unbind = acerhdf_unbind,
332 	.get_temp = acerhdf_get_ec_temp,
333 	.get_mode = acerhdf_get_mode,
334 	.set_mode = acerhdf_set_mode,
335 	.get_trip_type = acerhdf_get_trip_type,
336 	.get_trip_temp = acerhdf_get_trip_temp,
337 	.get_crit_temp = acerhdf_get_crit_temp,
338 };
339 
340 
341 /*
342  * cooling device callback functions
343  * get maximal fan cooling state
344  */
345 static int acerhdf_get_max_state(struct thermal_cooling_device *cdev,
346 				 unsigned long *state)
347 {
348 	*state = 1;
349 
350 	return 0;
351 }
352 
353 static int acerhdf_get_cur_state(struct thermal_cooling_device *cdev,
354 				 unsigned long *state)
355 {
356 	int err = 0, tmp;
357 
358 	err = acerhdf_get_fanstate(&tmp);
359 	if (err)
360 		return err;
361 
362 	*state = (tmp == ACERHDF_FAN_AUTO) ? 1 : 0;
363 	return 0;
364 }
365 
366 /* change current fan state - is overwritten when running in kernel mode */
367 static int acerhdf_set_cur_state(struct thermal_cooling_device *cdev,
368 				 unsigned long state)
369 {
370 	int cur_temp, cur_state, err = 0;
371 
372 	if (!kernelmode)
373 		return 0;
374 
375 	err = acerhdf_get_temp(&cur_temp);
376 	if (err) {
377 		pr_err("error reading temperature, hand off control to BIOS\n");
378 		goto err_out;
379 	}
380 
381 	err = acerhdf_get_fanstate(&cur_state);
382 	if (err) {
383 		pr_err("error reading fan state, hand off control to BIOS\n");
384 		goto err_out;
385 	}
386 
387 	if (state == 0) {
388 		/* turn fan off only if below fanoff temperature */
389 		if ((cur_state == ACERHDF_FAN_AUTO) &&
390 		    (cur_temp < fanoff))
391 			acerhdf_change_fanstate(ACERHDF_FAN_OFF);
392 	} else {
393 		if (cur_state == ACERHDF_FAN_OFF)
394 			acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
395 	}
396 	return 0;
397 
398 err_out:
399 	acerhdf_revert_to_bios_mode();
400 	return -EINVAL;
401 }
402 
403 /* bind fan callbacks to fan device */
404 struct thermal_cooling_device_ops acerhdf_cooling_ops = {
405 	.get_max_state = acerhdf_get_max_state,
406 	.get_cur_state = acerhdf_get_cur_state,
407 	.set_cur_state = acerhdf_set_cur_state,
408 };
409 
410 /* suspend / resume functionality */
411 static int acerhdf_suspend(struct platform_device *dev, pm_message_t state)
412 {
413 	if (kernelmode)
414 		acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
415 
416 	if (verbose)
417 		pr_notice("going suspend\n");
418 
419 	return 0;
420 }
421 
422 static int acerhdf_resume(struct platform_device *device)
423 {
424 	if (verbose)
425 		pr_notice("resuming\n");
426 
427 	return 0;
428 }
429 
430 static int __devinit acerhdf_probe(struct platform_device *device)
431 {
432 	return 0;
433 }
434 
435 static int acerhdf_remove(struct platform_device *device)
436 {
437 	return 0;
438 }
439 
440 struct platform_driver acerhdf_drv = {
441 	.driver = {
442 		.name = "acerhdf",
443 		.owner = THIS_MODULE,
444 	},
445 	.probe = acerhdf_probe,
446 	.remove = acerhdf_remove,
447 	.suspend = acerhdf_suspend,
448 	.resume = acerhdf_resume,
449 };
450 
451 
452 /* check hardware */
453 static int acerhdf_check_hardware(void)
454 {
455 	char const *vendor, *version, *product;
456 	int i;
457 
458 	/* get BIOS data */
459 	vendor  = dmi_get_system_info(DMI_SYS_VENDOR);
460 	version = dmi_get_system_info(DMI_BIOS_VERSION);
461 	product = dmi_get_system_info(DMI_PRODUCT_NAME);
462 
463 	pr_info("Acer Aspire One Fan driver, v.%s\n", DRV_VER);
464 
465 	if (!force_bios[0]) {
466 		if (strncmp(product, "AO", 2)) {
467 			pr_err("no Aspire One hardware found\n");
468 			return -EINVAL;
469 		}
470 	} else {
471 		pr_info("forcing BIOS version: %s\n", version);
472 		version = force_bios;
473 		kernelmode = 0;
474 	}
475 
476 	if (verbose)
477 		pr_info("BIOS info: %s %s, product: %s\n",
478 			vendor, version, product);
479 
480 	/* search BIOS version and vendor in BIOS settings table */
481 	for (i = 0; bios_tbl[i].version[0]; i++) {
482 		if (!strcmp(bios_tbl[i].vendor, vendor) &&
483 		    !strcmp(bios_tbl[i].version, version)) {
484 			bios_cfg = &bios_tbl[i];
485 			break;
486 		}
487 	}
488 
489 	if (!bios_cfg) {
490 		pr_err("unknown (unsupported) BIOS version %s/%s, "
491 			"please report, aborting!\n", vendor, version);
492 		return -EINVAL;
493 	}
494 
495 	/*
496 	 * if started with kernel mode off, prevent the kernel from switching
497 	 * off the fan
498 	 */
499 	if (!kernelmode) {
500 		pr_notice("Fan control off, to enable do:\n");
501 		pr_notice("echo -n \"enabled\" > "
502 			"/sys/class/thermal/thermal_zone0/mode\n");
503 	}
504 
505 	return 0;
506 }
507 
508 static int acerhdf_register_platform(void)
509 {
510 	int err = 0;
511 
512 	err = platform_driver_register(&acerhdf_drv);
513 	if (err)
514 		return err;
515 
516 	acerhdf_dev = platform_device_alloc("acerhdf", -1);
517 	platform_device_add(acerhdf_dev);
518 
519 	return 0;
520 }
521 
522 static void acerhdf_unregister_platform(void)
523 {
524 	if (!acerhdf_dev)
525 		return;
526 
527 	platform_device_del(acerhdf_dev);
528 	platform_driver_unregister(&acerhdf_drv);
529 }
530 
531 static int acerhdf_register_thermal(void)
532 {
533 	cl_dev = thermal_cooling_device_register("acerhdf-fan", NULL,
534 						 &acerhdf_cooling_ops);
535 
536 	if (IS_ERR(cl_dev))
537 		return -EINVAL;
538 
539 	thz_dev = thermal_zone_device_register("acerhdf", 1, NULL,
540 					      &acerhdf_dev_ops, 0, 0, 0,
541 					      (kernelmode) ? interval*1000 : 0);
542 	if (IS_ERR(thz_dev))
543 		return -EINVAL;
544 
545 	return 0;
546 }
547 
548 static void acerhdf_unregister_thermal(void)
549 {
550 	if (cl_dev) {
551 		thermal_cooling_device_unregister(cl_dev);
552 		cl_dev = NULL;
553 	}
554 
555 	if (thz_dev) {
556 		thermal_zone_device_unregister(thz_dev);
557 		thz_dev = NULL;
558 	}
559 }
560 
561 static int __init acerhdf_init(void)
562 {
563 	int err = 0;
564 
565 	err = acerhdf_check_hardware();
566 	if (err)
567 		goto out_err;
568 
569 	err = acerhdf_register_platform();
570 	if (err)
571 		goto err_unreg;
572 
573 	err = acerhdf_register_thermal();
574 	if (err)
575 		goto err_unreg;
576 
577 	return 0;
578 
579 err_unreg:
580 	acerhdf_unregister_thermal();
581 	acerhdf_unregister_platform();
582 
583 out_err:
584 	return -ENODEV;
585 }
586 
587 static void __exit acerhdf_exit(void)
588 {
589 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
590 	acerhdf_unregister_thermal();
591 	acerhdf_unregister_platform();
592 }
593 
594 MODULE_LICENSE("GPL");
595 MODULE_AUTHOR("Peter Feuerer");
596 MODULE_DESCRIPTION("Aspire One temperature and fan driver");
597 MODULE_ALIAS("dmi:*:*Acer*:*:");
598 MODULE_ALIAS("dmi:*:*Gateway*:*:");
599 MODULE_ALIAS("dmi:*:*Packard Bell*:*:");
600 
601 module_init(acerhdf_init);
602 module_exit(acerhdf_exit);
603