xref: /openbmc/linux/drivers/platform/x86/acerhdf.c (revision a06c488d)
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	bp (a) alien8.de
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 "0.7.0"
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 = 60000;
87 static unsigned int fanoff = 53000;
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 struct manualcmd {
123 	u8 mreg;
124 	u8 moff;
125 };
126 
127 /* default register and command to disable fan in manual mode */
128 static const struct manualcmd mcmd = {
129 	.mreg = 0x94,
130 	.moff = 0xff,
131 };
132 
133 /* BIOS settings */
134 struct bios_settings {
135 	const char *vendor;
136 	const char *product;
137 	const char *version;
138 	u8 fanreg;
139 	u8 tempreg;
140 	struct fancmd cmd;
141 	int mcmd_enable;
142 };
143 
144 /* Register addresses and values for different BIOS versions */
145 static const struct bios_settings bios_tbl[] = {
146 	/* AOA110 */
147 	{"Acer", "AOA110", "v0.3109", 0x55, 0x58, {0x1f, 0x00}, 0},
148 	{"Acer", "AOA110", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
149 	{"Acer", "AOA110", "v0.3301", 0x55, 0x58, {0xaf, 0x00}, 0},
150 	{"Acer", "AOA110", "v0.3304", 0x55, 0x58, {0xaf, 0x00}, 0},
151 	{"Acer", "AOA110", "v0.3305", 0x55, 0x58, {0xaf, 0x00}, 0},
152 	{"Acer", "AOA110", "v0.3307", 0x55, 0x58, {0xaf, 0x00}, 0},
153 	{"Acer", "AOA110", "v0.3308", 0x55, 0x58, {0x21, 0x00}, 0},
154 	{"Acer", "AOA110", "v0.3309", 0x55, 0x58, {0x21, 0x00}, 0},
155 	{"Acer", "AOA110", "v0.3310", 0x55, 0x58, {0x21, 0x00}, 0},
156 	/* AOA150 */
157 	{"Acer", "AOA150", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
158 	{"Acer", "AOA150", "v0.3301", 0x55, 0x58, {0x20, 0x00}, 0},
159 	{"Acer", "AOA150", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
160 	{"Acer", "AOA150", "v0.3305", 0x55, 0x58, {0x20, 0x00}, 0},
161 	{"Acer", "AOA150", "v0.3307", 0x55, 0x58, {0x20, 0x00}, 0},
162 	{"Acer", "AOA150", "v0.3308", 0x55, 0x58, {0x20, 0x00}, 0},
163 	{"Acer", "AOA150", "v0.3309", 0x55, 0x58, {0x20, 0x00}, 0},
164 	{"Acer", "AOA150", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
165 	/* LT1005u */
166 	{"Acer", "LT-10Q", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
167 	/* Acer 1410 */
168 	{"Acer", "Aspire 1410", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
169 	{"Acer", "Aspire 1410", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
170 	{"Acer", "Aspire 1410", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
171 	{"Acer", "Aspire 1410", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
172 	{"Acer", "Aspire 1410", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
173 	{"Acer", "Aspire 1410", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
174 	{"Acer", "Aspire 1410", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
175 	{"Acer", "Aspire 1410", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
176 	{"Acer", "Aspire 1410", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
177 	{"Acer", "Aspire 1410", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
178 	{"Acer", "Aspire 1410", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
179 	/* Acer 1810xx */
180 	{"Acer", "Aspire 1810TZ", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
181 	{"Acer", "Aspire 1810T",  "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
182 	{"Acer", "Aspire 1810TZ", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
183 	{"Acer", "Aspire 1810T",  "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
184 	{"Acer", "Aspire 1810TZ", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
185 	{"Acer", "Aspire 1810T",  "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
186 	{"Acer", "Aspire 1810TZ", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
187 	{"Acer", "Aspire 1810T",  "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
188 	{"Acer", "Aspire 1810TZ", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
189 	{"Acer", "Aspire 1810T",  "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
190 	{"Acer", "Aspire 1810TZ", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
191 	{"Acer", "Aspire 1810T",  "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
192 	{"Acer", "Aspire 1810TZ", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
193 	{"Acer", "Aspire 1810T",  "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
194 	{"Acer", "Aspire 1810TZ", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
195 	{"Acer", "Aspire 1810T",  "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
196 	{"Acer", "Aspire 1810TZ", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
197 	{"Acer", "Aspire 1810T",  "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
198 	{"Acer", "Aspire 1810TZ", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
199 	{"Acer", "Aspire 1810T",  "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
200 	{"Acer", "Aspire 1810TZ", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
201 	{"Acer", "Aspire 1810T",  "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
202 	/* Acer 5755G */
203 	{"Acer", "Aspire 5755G",  "V1.20",   0xab, 0xb4, {0x00, 0x08}, 0},
204 	{"Acer", "Aspire 5755G",  "V1.21",   0xab, 0xb3, {0x00, 0x08}, 0},
205 	/* Acer 521 */
206 	{"Acer", "AO521", "V1.11", 0x55, 0x58, {0x1f, 0x00}, 0},
207 	/* Acer 531 */
208 	{"Acer", "AO531h", "v0.3104", 0x55, 0x58, {0x20, 0x00}, 0},
209 	{"Acer", "AO531h", "v0.3201", 0x55, 0x58, {0x20, 0x00}, 0},
210 	{"Acer", "AO531h", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
211 	/* Acer 751 */
212 	{"Acer", "AO751h", "V0.3206", 0x55, 0x58, {0x21, 0x00}, 0},
213 	{"Acer", "AO751h", "V0.3212", 0x55, 0x58, {0x21, 0x00}, 0},
214 	/* Acer 753 */
215 	{"Acer", "Aspire One 753", "V1.24", 0x93, 0xac, {0x14, 0x04}, 1},
216 	/* Acer 1825 */
217 	{"Acer", "Aspire 1825PTZ", "V1.3118", 0x55, 0x58, {0x9e, 0x00}, 0},
218 	{"Acer", "Aspire 1825PTZ", "V1.3127", 0x55, 0x58, {0x9e, 0x00}, 0},
219 	/* Acer Extensa 5420 */
220 	{"Acer", "Extensa 5420", "V1.17", 0x93, 0xac, {0x14, 0x04}, 1},
221 	/* Acer Aspire 5315 */
222 	{"Acer", "Aspire 5315", "V1.19", 0x93, 0xac, {0x14, 0x04}, 1},
223 	/* Acer Aspire 5739 */
224 	{"Acer", "Aspire 5739G", "V1.3311", 0x55, 0x58, {0x20, 0x00}, 0},
225 	/* Acer TravelMate 7730 */
226 	{"Acer", "TravelMate 7730G", "v0.3509", 0x55, 0x58, {0xaf, 0x00}, 0},
227 	/* Acer TravelMate TM8573T */
228 	{"Acer", "TM8573T", "V1.13", 0x93, 0xa8, {0x14, 0x04}, 1},
229 	/* Gateway */
230 	{"Gateway", "AOA110", "v0.3103",  0x55, 0x58, {0x21, 0x00}, 0},
231 	{"Gateway", "AOA150", "v0.3103",  0x55, 0x58, {0x20, 0x00}, 0},
232 	{"Gateway", "LT31",   "v1.3103",  0x55, 0x58, {0x9e, 0x00}, 0},
233 	{"Gateway", "LT31",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
234 	{"Gateway", "LT31",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
235 	{"Gateway", "LT31",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
236 	/* Packard Bell */
237 	{"Packard Bell", "DOA150",  "v0.3104",  0x55, 0x58, {0x21, 0x00}, 0},
238 	{"Packard Bell", "DOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
239 	{"Packard Bell", "AOA110",  "v0.3105",  0x55, 0x58, {0x21, 0x00}, 0},
240 	{"Packard Bell", "AOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
241 	{"Packard Bell", "ENBFT",   "V1.3118",  0x55, 0x58, {0x9e, 0x00}, 0},
242 	{"Packard Bell", "ENBFT",   "V1.3127",  0x55, 0x58, {0x9e, 0x00}, 0},
243 	{"Packard Bell", "DOTMU",   "v1.3303",  0x55, 0x58, {0x9e, 0x00}, 0},
244 	{"Packard Bell", "DOTMU",   "v0.3120",  0x55, 0x58, {0x9e, 0x00}, 0},
245 	{"Packard Bell", "DOTMU",   "v0.3108",  0x55, 0x58, {0x9e, 0x00}, 0},
246 	{"Packard Bell", "DOTMU",   "v0.3113",  0x55, 0x58, {0x9e, 0x00}, 0},
247 	{"Packard Bell", "DOTMU",   "v0.3115",  0x55, 0x58, {0x9e, 0x00}, 0},
248 	{"Packard Bell", "DOTMU",   "v0.3117",  0x55, 0x58, {0x9e, 0x00}, 0},
249 	{"Packard Bell", "DOTMU",   "v0.3119",  0x55, 0x58, {0x9e, 0x00}, 0},
250 	{"Packard Bell", "DOTMU",   "v1.3204",  0x55, 0x58, {0x9e, 0x00}, 0},
251 	{"Packard Bell", "DOTMA",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
252 	{"Packard Bell", "DOTMA",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
253 	{"Packard Bell", "DOTMA",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
254 	{"Packard Bell", "DOTVR46", "v1.3308",  0x55, 0x58, {0x9e, 0x00}, 0},
255 	/* pewpew-terminator */
256 	{"", "", "", 0, 0, {0, 0}, 0}
257 };
258 
259 static const struct bios_settings *bios_cfg __read_mostly;
260 
261 /*
262  * this struct is used to instruct thermal layer to use bang_bang instead of
263  * default governor for acerhdf
264  */
265 static struct thermal_zone_params acerhdf_zone_params = {
266 	.governor_name = "bang_bang",
267 };
268 
269 static int acerhdf_get_temp(int *temp)
270 {
271 	u8 read_temp;
272 
273 	if (ec_read(bios_cfg->tempreg, &read_temp))
274 		return -EINVAL;
275 
276 	*temp = read_temp * 1000;
277 
278 	return 0;
279 }
280 
281 static int acerhdf_get_fanstate(int *state)
282 {
283 	u8 fan;
284 
285 	if (ec_read(bios_cfg->fanreg, &fan))
286 		return -EINVAL;
287 
288 	if (fan != bios_cfg->cmd.cmd_off)
289 		*state = ACERHDF_FAN_AUTO;
290 	else
291 		*state = ACERHDF_FAN_OFF;
292 
293 	return 0;
294 }
295 
296 static void acerhdf_change_fanstate(int state)
297 {
298 	unsigned char cmd;
299 
300 	if (verbose)
301 		pr_notice("fan %s\n", state == ACERHDF_FAN_OFF ? "OFF" : "ON");
302 
303 	if ((state != ACERHDF_FAN_OFF) && (state != ACERHDF_FAN_AUTO)) {
304 		pr_err("invalid fan state %d requested, setting to auto!\n",
305 		       state);
306 		state = ACERHDF_FAN_AUTO;
307 	}
308 
309 	cmd = (state == ACERHDF_FAN_OFF) ? bios_cfg->cmd.cmd_off
310 					 : bios_cfg->cmd.cmd_auto;
311 	fanstate = state;
312 
313 	ec_write(bios_cfg->fanreg, cmd);
314 
315 	if (bios_cfg->mcmd_enable && state == ACERHDF_FAN_OFF) {
316 		if (verbose)
317 			pr_notice("turning off fan manually\n");
318 		ec_write(mcmd.mreg, mcmd.moff);
319 	}
320 }
321 
322 static void acerhdf_check_param(struct thermal_zone_device *thermal)
323 {
324 	if (fanon > ACERHDF_MAX_FANON) {
325 		pr_err("fanon temperature too high, set to %d\n",
326 		       ACERHDF_MAX_FANON);
327 		fanon = ACERHDF_MAX_FANON;
328 	}
329 
330 	if (kernelmode && prev_interval != interval) {
331 		if (interval > ACERHDF_MAX_INTERVAL) {
332 			pr_err("interval too high, set to %d\n",
333 			       ACERHDF_MAX_INTERVAL);
334 			interval = ACERHDF_MAX_INTERVAL;
335 		}
336 		if (verbose)
337 			pr_notice("interval changed to: %d\n", interval);
338 		thermal->polling_delay = interval*1000;
339 		prev_interval = interval;
340 	}
341 }
342 
343 /*
344  * This is the thermal zone callback which does the delayed polling of the fan
345  * state. We do check /sysfs-originating settings here in acerhdf_check_param()
346  * as late as the polling interval is since we can't do that in the respective
347  * accessors of the module parameters.
348  */
349 static int acerhdf_get_ec_temp(struct thermal_zone_device *thermal, int *t)
350 {
351 	int temp, err = 0;
352 
353 	acerhdf_check_param(thermal);
354 
355 	err = acerhdf_get_temp(&temp);
356 	if (err)
357 		return err;
358 
359 	if (verbose)
360 		pr_notice("temp %d\n", temp);
361 
362 	*t = temp;
363 	return 0;
364 }
365 
366 static int acerhdf_bind(struct thermal_zone_device *thermal,
367 			struct thermal_cooling_device *cdev)
368 {
369 	/* if the cooling device is the one from acerhdf bind it */
370 	if (cdev != cl_dev)
371 		return 0;
372 
373 	if (thermal_zone_bind_cooling_device(thermal, 0, cdev,
374 			THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
375 			THERMAL_WEIGHT_DEFAULT)) {
376 		pr_err("error binding cooling dev\n");
377 		return -EINVAL;
378 	}
379 	return 0;
380 }
381 
382 static int acerhdf_unbind(struct thermal_zone_device *thermal,
383 			  struct thermal_cooling_device *cdev)
384 {
385 	if (cdev != cl_dev)
386 		return 0;
387 
388 	if (thermal_zone_unbind_cooling_device(thermal, 0, cdev)) {
389 		pr_err("error unbinding cooling dev\n");
390 		return -EINVAL;
391 	}
392 	return 0;
393 }
394 
395 static inline void acerhdf_revert_to_bios_mode(void)
396 {
397 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
398 	kernelmode = 0;
399 	if (thz_dev)
400 		thz_dev->polling_delay = 0;
401 	pr_notice("kernel mode fan control OFF\n");
402 }
403 static inline void acerhdf_enable_kernelmode(void)
404 {
405 	kernelmode = 1;
406 
407 	thz_dev->polling_delay = interval*1000;
408 	thermal_zone_device_update(thz_dev);
409 	pr_notice("kernel mode fan control ON\n");
410 }
411 
412 static int acerhdf_get_mode(struct thermal_zone_device *thermal,
413 			    enum thermal_device_mode *mode)
414 {
415 	if (verbose)
416 		pr_notice("kernel mode fan control %d\n", kernelmode);
417 
418 	*mode = (kernelmode) ? THERMAL_DEVICE_ENABLED
419 			     : THERMAL_DEVICE_DISABLED;
420 
421 	return 0;
422 }
423 
424 /*
425  * set operation mode;
426  * enabled: the thermal layer of the kernel takes care about
427  *          the temperature and the fan.
428  * disabled: the BIOS takes control of the fan.
429  */
430 static int acerhdf_set_mode(struct thermal_zone_device *thermal,
431 			    enum thermal_device_mode mode)
432 {
433 	if (mode == THERMAL_DEVICE_DISABLED && kernelmode)
434 		acerhdf_revert_to_bios_mode();
435 	else if (mode == THERMAL_DEVICE_ENABLED && !kernelmode)
436 		acerhdf_enable_kernelmode();
437 
438 	return 0;
439 }
440 
441 static int acerhdf_get_trip_type(struct thermal_zone_device *thermal, int trip,
442 				 enum thermal_trip_type *type)
443 {
444 	if (trip == 0)
445 		*type = THERMAL_TRIP_ACTIVE;
446 	else if (trip == 1)
447 		*type = THERMAL_TRIP_CRITICAL;
448 	else
449 		return -EINVAL;
450 
451 	return 0;
452 }
453 
454 static int acerhdf_get_trip_hyst(struct thermal_zone_device *thermal, int trip,
455 				 int *temp)
456 {
457 	if (trip != 0)
458 		return -EINVAL;
459 
460 	*temp = fanon - fanoff;
461 
462 	return 0;
463 }
464 
465 static int acerhdf_get_trip_temp(struct thermal_zone_device *thermal, int trip,
466 				 int *temp)
467 {
468 	if (trip == 0)
469 		*temp = fanon;
470 	else if (trip == 1)
471 		*temp = ACERHDF_TEMP_CRIT;
472 	else
473 		return -EINVAL;
474 
475 	return 0;
476 }
477 
478 static int acerhdf_get_crit_temp(struct thermal_zone_device *thermal,
479 				 int *temperature)
480 {
481 	*temperature = ACERHDF_TEMP_CRIT;
482 	return 0;
483 }
484 
485 /* bind callback functions to thermalzone */
486 static struct thermal_zone_device_ops acerhdf_dev_ops = {
487 	.bind = acerhdf_bind,
488 	.unbind = acerhdf_unbind,
489 	.get_temp = acerhdf_get_ec_temp,
490 	.get_mode = acerhdf_get_mode,
491 	.set_mode = acerhdf_set_mode,
492 	.get_trip_type = acerhdf_get_trip_type,
493 	.get_trip_hyst = acerhdf_get_trip_hyst,
494 	.get_trip_temp = acerhdf_get_trip_temp,
495 	.get_crit_temp = acerhdf_get_crit_temp,
496 };
497 
498 
499 /*
500  * cooling device callback functions
501  * get maximal fan cooling state
502  */
503 static int acerhdf_get_max_state(struct thermal_cooling_device *cdev,
504 				 unsigned long *state)
505 {
506 	*state = 1;
507 
508 	return 0;
509 }
510 
511 static int acerhdf_get_cur_state(struct thermal_cooling_device *cdev,
512 				 unsigned long *state)
513 {
514 	int err = 0, tmp;
515 
516 	err = acerhdf_get_fanstate(&tmp);
517 	if (err)
518 		return err;
519 
520 	*state = (tmp == ACERHDF_FAN_AUTO) ? 1 : 0;
521 	return 0;
522 }
523 
524 /* change current fan state - is overwritten when running in kernel mode */
525 static int acerhdf_set_cur_state(struct thermal_cooling_device *cdev,
526 				 unsigned long state)
527 {
528 	int cur_temp, cur_state, err = 0;
529 
530 	if (!kernelmode)
531 		return 0;
532 
533 	err = acerhdf_get_temp(&cur_temp);
534 	if (err) {
535 		pr_err("error reading temperature, hand off control to BIOS\n");
536 		goto err_out;
537 	}
538 
539 	err = acerhdf_get_fanstate(&cur_state);
540 	if (err) {
541 		pr_err("error reading fan state, hand off control to BIOS\n");
542 		goto err_out;
543 	}
544 
545 	if (state == 0) {
546 		if (cur_state == ACERHDF_FAN_AUTO)
547 			acerhdf_change_fanstate(ACERHDF_FAN_OFF);
548 	} else {
549 		if (cur_state == ACERHDF_FAN_OFF)
550 			acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
551 	}
552 	return 0;
553 
554 err_out:
555 	acerhdf_revert_to_bios_mode();
556 	return -EINVAL;
557 }
558 
559 /* bind fan callbacks to fan device */
560 static struct thermal_cooling_device_ops acerhdf_cooling_ops = {
561 	.get_max_state = acerhdf_get_max_state,
562 	.get_cur_state = acerhdf_get_cur_state,
563 	.set_cur_state = acerhdf_set_cur_state,
564 };
565 
566 /* suspend / resume functionality */
567 static int acerhdf_suspend(struct device *dev)
568 {
569 	if (kernelmode)
570 		acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
571 
572 	if (verbose)
573 		pr_notice("going suspend\n");
574 
575 	return 0;
576 }
577 
578 static int acerhdf_probe(struct platform_device *device)
579 {
580 	return 0;
581 }
582 
583 static int acerhdf_remove(struct platform_device *device)
584 {
585 	return 0;
586 }
587 
588 static const struct dev_pm_ops acerhdf_pm_ops = {
589 	.suspend = acerhdf_suspend,
590 	.freeze  = acerhdf_suspend,
591 };
592 
593 static struct platform_driver acerhdf_driver = {
594 	.driver = {
595 		.name  = "acerhdf",
596 		.pm    = &acerhdf_pm_ops,
597 	},
598 	.probe = acerhdf_probe,
599 	.remove = acerhdf_remove,
600 };
601 
602 /* checks if str begins with start */
603 static int str_starts_with(const char *str, const char *start)
604 {
605 	unsigned long str_len = 0, start_len = 0;
606 
607 	str_len = strlen(str);
608 	start_len = strlen(start);
609 
610 	if (str_len >= start_len &&
611 			!strncmp(str, start, start_len))
612 		return 1;
613 
614 	return 0;
615 }
616 
617 /* check hardware */
618 static int acerhdf_check_hardware(void)
619 {
620 	char const *vendor, *version, *product;
621 	const struct bios_settings *bt = NULL;
622 
623 	/* get BIOS data */
624 	vendor  = dmi_get_system_info(DMI_SYS_VENDOR);
625 	version = dmi_get_system_info(DMI_BIOS_VERSION);
626 	product = dmi_get_system_info(DMI_PRODUCT_NAME);
627 
628 	if (!vendor || !version || !product) {
629 		pr_err("error getting hardware information\n");
630 		return -EINVAL;
631 	}
632 
633 	pr_info("Acer Aspire One Fan driver, v.%s\n", DRV_VER);
634 
635 	if (force_bios[0]) {
636 		version = force_bios;
637 		pr_info("forcing BIOS version: %s\n", version);
638 		kernelmode = 0;
639 	}
640 
641 	if (force_product[0]) {
642 		product = force_product;
643 		pr_info("forcing BIOS product: %s\n", product);
644 		kernelmode = 0;
645 	}
646 
647 	if (verbose)
648 		pr_info("BIOS info: %s %s, product: %s\n",
649 			vendor, version, product);
650 
651 	/* search BIOS version and vendor in BIOS settings table */
652 	for (bt = bios_tbl; bt->vendor[0]; bt++) {
653 		/*
654 		 * check if actual hardware BIOS vendor, product and version
655 		 * IDs start with the strings of BIOS table entry
656 		 */
657 		if (str_starts_with(vendor, bt->vendor) &&
658 				str_starts_with(product, bt->product) &&
659 				str_starts_with(version, bt->version)) {
660 			bios_cfg = bt;
661 			break;
662 		}
663 	}
664 
665 	if (!bios_cfg) {
666 		pr_err("unknown (unsupported) BIOS version %s/%s/%s, please report, aborting!\n",
667 		       vendor, product, version);
668 		return -EINVAL;
669 	}
670 
671 	/*
672 	 * if started with kernel mode off, prevent the kernel from switching
673 	 * off the fan
674 	 */
675 	if (!kernelmode) {
676 		pr_notice("Fan control off, to enable do:\n");
677 		pr_notice("echo -n \"enabled\" > /sys/class/thermal/thermal_zone0/mode\n");
678 	}
679 
680 	return 0;
681 }
682 
683 static int acerhdf_register_platform(void)
684 {
685 	int err = 0;
686 
687 	err = platform_driver_register(&acerhdf_driver);
688 	if (err)
689 		return err;
690 
691 	acerhdf_dev = platform_device_alloc("acerhdf", -1);
692 	if (!acerhdf_dev) {
693 		err = -ENOMEM;
694 		goto err_device_alloc;
695 	}
696 	err = platform_device_add(acerhdf_dev);
697 	if (err)
698 		goto err_device_add;
699 
700 	return 0;
701 
702 err_device_add:
703 	platform_device_put(acerhdf_dev);
704 err_device_alloc:
705 	platform_driver_unregister(&acerhdf_driver);
706 	return err;
707 }
708 
709 static void acerhdf_unregister_platform(void)
710 {
711 	platform_device_unregister(acerhdf_dev);
712 	platform_driver_unregister(&acerhdf_driver);
713 }
714 
715 static int acerhdf_register_thermal(void)
716 {
717 	cl_dev = thermal_cooling_device_register("acerhdf-fan", NULL,
718 						 &acerhdf_cooling_ops);
719 
720 	if (IS_ERR(cl_dev))
721 		return -EINVAL;
722 
723 	thz_dev = thermal_zone_device_register("acerhdf", 2, 0, NULL,
724 					      &acerhdf_dev_ops,
725 					      &acerhdf_zone_params, 0,
726 					      (kernelmode) ? interval*1000 : 0);
727 	if (IS_ERR(thz_dev))
728 		return -EINVAL;
729 
730 	if (strcmp(thz_dev->governor->name,
731 				acerhdf_zone_params.governor_name)) {
732 		pr_err("Didn't get thermal governor %s, perhaps not compiled into thermal subsystem.\n",
733 				acerhdf_zone_params.governor_name);
734 		return -EINVAL;
735 	}
736 
737 	return 0;
738 }
739 
740 static void acerhdf_unregister_thermal(void)
741 {
742 	if (cl_dev) {
743 		thermal_cooling_device_unregister(cl_dev);
744 		cl_dev = NULL;
745 	}
746 
747 	if (thz_dev) {
748 		thermal_zone_device_unregister(thz_dev);
749 		thz_dev = NULL;
750 	}
751 }
752 
753 static int __init acerhdf_init(void)
754 {
755 	int err = 0;
756 
757 	err = acerhdf_check_hardware();
758 	if (err)
759 		goto out_err;
760 
761 	err = acerhdf_register_platform();
762 	if (err)
763 		goto out_err;
764 
765 	err = acerhdf_register_thermal();
766 	if (err)
767 		goto err_unreg;
768 
769 	return 0;
770 
771 err_unreg:
772 	acerhdf_unregister_thermal();
773 	acerhdf_unregister_platform();
774 
775 out_err:
776 	return err;
777 }
778 
779 static void __exit acerhdf_exit(void)
780 {
781 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
782 	acerhdf_unregister_thermal();
783 	acerhdf_unregister_platform();
784 }
785 
786 MODULE_LICENSE("GPL");
787 MODULE_AUTHOR("Peter Feuerer");
788 MODULE_DESCRIPTION("Aspire One temperature and fan driver");
789 MODULE_ALIAS("dmi:*:*Acer*:pnAOA*:");
790 MODULE_ALIAS("dmi:*:*Acer*:pnAO751h*:");
791 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1410*:");
792 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1810*:");
793 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5755G:");
794 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1825PTZ:");
795 MODULE_ALIAS("dmi:*:*Acer*:pnAO521*:");
796 MODULE_ALIAS("dmi:*:*Acer*:pnAO531*:");
797 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5739G:");
798 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*One*753:");
799 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5315:");
800 MODULE_ALIAS("dmi:*:*Acer*:TravelMate*7730G:");
801 MODULE_ALIAS("dmi:*:*Acer*:TM8573T:");
802 MODULE_ALIAS("dmi:*:*Gateway*:pnAOA*:");
803 MODULE_ALIAS("dmi:*:*Gateway*:pnLT31*:");
804 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnAOA*:");
805 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOA*:");
806 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMU*:");
807 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnENBFT*:");
808 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMA*:");
809 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTVR46*:");
810 MODULE_ALIAS("dmi:*:*Acer*:pnExtensa 5420*:");
811 
812 module_init(acerhdf_init);
813 module_exit(acerhdf_exit);
814