xref: /openbmc/linux/drivers/platform/x86/acerhdf.c (revision d4fd6347)
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 list_supported;
90 static unsigned int fanstate = ACERHDF_FAN_AUTO;
91 static char force_bios[16];
92 static char force_product[16];
93 static unsigned int prev_interval;
94 static struct thermal_zone_device *thz_dev;
95 static struct thermal_cooling_device *cl_dev;
96 static 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(list_supported, uint, 0600);
109 MODULE_PARM_DESC(list_supported, "List supported models and BIOS versions");
110 module_param_string(force_bios, force_bios, 16, 0);
111 MODULE_PARM_DESC(force_bios, "Pretend system has this known supported BIOS version");
112 module_param_string(force_product, force_product, 16, 0);
113 MODULE_PARM_DESC(force_product, "Pretend system is this known supported model");
114 
115 /*
116  * cmd_off: to switch the fan completely off and 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 cmd_auto;
123 };
124 
125 struct manualcmd {
126 	u8 mreg;
127 	u8 moff;
128 };
129 
130 /* default register and command to disable fan in manual mode */
131 static const struct manualcmd mcmd = {
132 	.mreg = 0x94,
133 	.moff = 0xff,
134 };
135 
136 /* BIOS settings - only used during probe */
137 struct bios_settings {
138 	const char *vendor;
139 	const char *product;
140 	const char *version;
141 	u8 fanreg;
142 	u8 tempreg;
143 	struct fancmd cmd;
144 	int mcmd_enable;
145 };
146 
147 /* This could be a daughter struct in the above, but not worth the redirect */
148 struct ctrl_settings {
149 	u8 fanreg;
150 	u8 tempreg;
151 	struct fancmd cmd;
152 	int mcmd_enable;
153 };
154 
155 static struct ctrl_settings ctrl_cfg __read_mostly;
156 
157 /* Register addresses and values for different BIOS versions */
158 static const struct bios_settings bios_tbl[] __initconst = {
159 	/* AOA110 */
160 	{"Acer", "AOA110", "v0.3109", 0x55, 0x58, {0x1f, 0x00}, 0},
161 	{"Acer", "AOA110", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
162 	{"Acer", "AOA110", "v0.3301", 0x55, 0x58, {0xaf, 0x00}, 0},
163 	{"Acer", "AOA110", "v0.3304", 0x55, 0x58, {0xaf, 0x00}, 0},
164 	{"Acer", "AOA110", "v0.3305", 0x55, 0x58, {0xaf, 0x00}, 0},
165 	{"Acer", "AOA110", "v0.3307", 0x55, 0x58, {0xaf, 0x00}, 0},
166 	{"Acer", "AOA110", "v0.3308", 0x55, 0x58, {0x21, 0x00}, 0},
167 	{"Acer", "AOA110", "v0.3309", 0x55, 0x58, {0x21, 0x00}, 0},
168 	{"Acer", "AOA110", "v0.3310", 0x55, 0x58, {0x21, 0x00}, 0},
169 	/* AOA150 */
170 	{"Acer", "AOA150", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
171 	{"Acer", "AOA150", "v0.3301", 0x55, 0x58, {0x20, 0x00}, 0},
172 	{"Acer", "AOA150", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
173 	{"Acer", "AOA150", "v0.3305", 0x55, 0x58, {0x20, 0x00}, 0},
174 	{"Acer", "AOA150", "v0.3307", 0x55, 0x58, {0x20, 0x00}, 0},
175 	{"Acer", "AOA150", "v0.3308", 0x55, 0x58, {0x20, 0x00}, 0},
176 	{"Acer", "AOA150", "v0.3309", 0x55, 0x58, {0x20, 0x00}, 0},
177 	{"Acer", "AOA150", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
178 	/* LT1005u */
179 	{"Acer", "LT-10Q", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
180 	/* Acer 1410 */
181 	{"Acer", "Aspire 1410", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
182 	{"Acer", "Aspire 1410", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
183 	{"Acer", "Aspire 1410", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
184 	{"Acer", "Aspire 1410", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
185 	{"Acer", "Aspire 1410", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
186 	{"Acer", "Aspire 1410", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
187 	{"Acer", "Aspire 1410", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
188 	{"Acer", "Aspire 1410", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
189 	{"Acer", "Aspire 1410", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
190 	{"Acer", "Aspire 1410", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
191 	{"Acer", "Aspire 1410", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
192 	/* Acer 1810xx */
193 	{"Acer", "Aspire 1810TZ", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
194 	{"Acer", "Aspire 1810T",  "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
195 	{"Acer", "Aspire 1810TZ", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
196 	{"Acer", "Aspire 1810T",  "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
197 	{"Acer", "Aspire 1810TZ", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
198 	{"Acer", "Aspire 1810T",  "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
199 	{"Acer", "Aspire 1810TZ", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
200 	{"Acer", "Aspire 1810T",  "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
201 	{"Acer", "Aspire 1810TZ", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
202 	{"Acer", "Aspire 1810T",  "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
203 	{"Acer", "Aspire 1810TZ", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
204 	{"Acer", "Aspire 1810T",  "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
205 	{"Acer", "Aspire 1810TZ", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
206 	{"Acer", "Aspire 1810T",  "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
207 	{"Acer", "Aspire 1810TZ", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
208 	{"Acer", "Aspire 1810T",  "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
209 	{"Acer", "Aspire 1810TZ", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
210 	{"Acer", "Aspire 1810T",  "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
211 	{"Acer", "Aspire 1810TZ", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
212 	{"Acer", "Aspire 1810T",  "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
213 	{"Acer", "Aspire 1810TZ", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
214 	{"Acer", "Aspire 1810T",  "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
215 	/* Acer 5755G */
216 	{"Acer", "Aspire 5755G",  "V1.20",   0xab, 0xb4, {0x00, 0x08}, 0},
217 	{"Acer", "Aspire 5755G",  "V1.21",   0xab, 0xb3, {0x00, 0x08}, 0},
218 	/* Acer 521 */
219 	{"Acer", "AO521", "V1.11", 0x55, 0x58, {0x1f, 0x00}, 0},
220 	/* Acer 531 */
221 	{"Acer", "AO531h", "v0.3104", 0x55, 0x58, {0x20, 0x00}, 0},
222 	{"Acer", "AO531h", "v0.3201", 0x55, 0x58, {0x20, 0x00}, 0},
223 	{"Acer", "AO531h", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
224 	/* Acer 751 */
225 	{"Acer", "AO751h", "V0.3206", 0x55, 0x58, {0x21, 0x00}, 0},
226 	{"Acer", "AO751h", "V0.3212", 0x55, 0x58, {0x21, 0x00}, 0},
227 	/* Acer 753 */
228 	{"Acer", "Aspire One 753", "V1.24", 0x93, 0xac, {0x14, 0x04}, 1},
229 	/* Acer 1825 */
230 	{"Acer", "Aspire 1825PTZ", "V1.3118", 0x55, 0x58, {0x9e, 0x00}, 0},
231 	{"Acer", "Aspire 1825PTZ", "V1.3127", 0x55, 0x58, {0x9e, 0x00}, 0},
232 	/* Acer Extensa 5420 */
233 	{"Acer", "Extensa 5420", "V1.17", 0x93, 0xac, {0x14, 0x04}, 1},
234 	/* Acer Aspire 5315 */
235 	{"Acer", "Aspire 5315", "V1.19", 0x93, 0xac, {0x14, 0x04}, 1},
236 	/* Acer Aspire 5739 */
237 	{"Acer", "Aspire 5739G", "V1.3311", 0x55, 0x58, {0x20, 0x00}, 0},
238 	/* Acer TravelMate 7730 */
239 	{"Acer", "TravelMate 7730G", "v0.3509", 0x55, 0x58, {0xaf, 0x00}, 0},
240 	/* Acer TravelMate TM8573T */
241 	{"Acer", "TM8573T", "V1.13", 0x93, 0xa8, {0x14, 0x04}, 1},
242 	/* Gateway */
243 	{"Gateway", "AOA110", "v0.3103",  0x55, 0x58, {0x21, 0x00}, 0},
244 	{"Gateway", "AOA150", "v0.3103",  0x55, 0x58, {0x20, 0x00}, 0},
245 	{"Gateway", "LT31",   "v1.3103",  0x55, 0x58, {0x9e, 0x00}, 0},
246 	{"Gateway", "LT31",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
247 	{"Gateway", "LT31",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
248 	{"Gateway", "LT31",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
249 	{"Gateway", "LT31",   "v1.3307",  0x55, 0x58, {0x9e, 0x00}, 0},
250 	/* Packard Bell */
251 	{"Packard Bell", "DOA150",  "v0.3104",  0x55, 0x58, {0x21, 0x00}, 0},
252 	{"Packard Bell", "DOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
253 	{"Packard Bell", "AOA110",  "v0.3105",  0x55, 0x58, {0x21, 0x00}, 0},
254 	{"Packard Bell", "AOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
255 	{"Packard Bell", "ENBFT",   "V1.3118",  0x55, 0x58, {0x9e, 0x00}, 0},
256 	{"Packard Bell", "ENBFT",   "V1.3127",  0x55, 0x58, {0x9e, 0x00}, 0},
257 	{"Packard Bell", "DOTMU",   "v1.3303",  0x55, 0x58, {0x9e, 0x00}, 0},
258 	{"Packard Bell", "DOTMU",   "v0.3120",  0x55, 0x58, {0x9e, 0x00}, 0},
259 	{"Packard Bell", "DOTMU",   "v0.3108",  0x55, 0x58, {0x9e, 0x00}, 0},
260 	{"Packard Bell", "DOTMU",   "v0.3113",  0x55, 0x58, {0x9e, 0x00}, 0},
261 	{"Packard Bell", "DOTMU",   "v0.3115",  0x55, 0x58, {0x9e, 0x00}, 0},
262 	{"Packard Bell", "DOTMU",   "v0.3117",  0x55, 0x58, {0x9e, 0x00}, 0},
263 	{"Packard Bell", "DOTMU",   "v0.3119",  0x55, 0x58, {0x9e, 0x00}, 0},
264 	{"Packard Bell", "DOTMU",   "v1.3204",  0x55, 0x58, {0x9e, 0x00}, 0},
265 	{"Packard Bell", "DOTMA",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
266 	{"Packard Bell", "DOTMA",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
267 	{"Packard Bell", "DOTMA",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
268 	{"Packard Bell", "DOTVR46", "v1.3308",  0x55, 0x58, {0x9e, 0x00}, 0},
269 	/* pewpew-terminator */
270 	{"", "", "", 0, 0, {0, 0}, 0}
271 };
272 
273 /*
274  * this struct is used to instruct thermal layer to use bang_bang instead of
275  * default governor for acerhdf
276  */
277 static struct thermal_zone_params acerhdf_zone_params = {
278 	.governor_name = "bang_bang",
279 };
280 
281 static int acerhdf_get_temp(int *temp)
282 {
283 	u8 read_temp;
284 
285 	if (ec_read(ctrl_cfg.tempreg, &read_temp))
286 		return -EINVAL;
287 
288 	*temp = read_temp * 1000;
289 
290 	return 0;
291 }
292 
293 static int acerhdf_get_fanstate(int *state)
294 {
295 	u8 fan;
296 
297 	if (ec_read(ctrl_cfg.fanreg, &fan))
298 		return -EINVAL;
299 
300 	if (fan != ctrl_cfg.cmd.cmd_off)
301 		*state = ACERHDF_FAN_AUTO;
302 	else
303 		*state = ACERHDF_FAN_OFF;
304 
305 	return 0;
306 }
307 
308 static void acerhdf_change_fanstate(int state)
309 {
310 	unsigned char cmd;
311 
312 	if (verbose)
313 		pr_notice("fan %s\n", state == ACERHDF_FAN_OFF ? "OFF" : "ON");
314 
315 	if ((state != ACERHDF_FAN_OFF) && (state != ACERHDF_FAN_AUTO)) {
316 		pr_err("invalid fan state %d requested, setting to auto!\n",
317 		       state);
318 		state = ACERHDF_FAN_AUTO;
319 	}
320 
321 	cmd = (state == ACERHDF_FAN_OFF) ? ctrl_cfg.cmd.cmd_off
322 					 : ctrl_cfg.cmd.cmd_auto;
323 	fanstate = state;
324 
325 	ec_write(ctrl_cfg.fanreg, cmd);
326 
327 	if (ctrl_cfg.mcmd_enable && state == ACERHDF_FAN_OFF) {
328 		if (verbose)
329 			pr_notice("turning off fan manually\n");
330 		ec_write(mcmd.mreg, mcmd.moff);
331 	}
332 }
333 
334 static void acerhdf_check_param(struct thermal_zone_device *thermal)
335 {
336 	if (fanon > ACERHDF_MAX_FANON) {
337 		pr_err("fanon temperature too high, set to %d\n",
338 		       ACERHDF_MAX_FANON);
339 		fanon = ACERHDF_MAX_FANON;
340 	}
341 
342 	if (kernelmode && prev_interval != interval) {
343 		if (interval > ACERHDF_MAX_INTERVAL) {
344 			pr_err("interval too high, set to %d\n",
345 			       ACERHDF_MAX_INTERVAL);
346 			interval = ACERHDF_MAX_INTERVAL;
347 		}
348 		if (verbose)
349 			pr_notice("interval changed to: %d\n", interval);
350 		thermal->polling_delay = interval*1000;
351 		prev_interval = interval;
352 	}
353 }
354 
355 /*
356  * This is the thermal zone callback which does the delayed polling of the fan
357  * state. We do check /sysfs-originating settings here in acerhdf_check_param()
358  * as late as the polling interval is since we can't do that in the respective
359  * accessors of the module parameters.
360  */
361 static int acerhdf_get_ec_temp(struct thermal_zone_device *thermal, int *t)
362 {
363 	int temp, err = 0;
364 
365 	acerhdf_check_param(thermal);
366 
367 	err = acerhdf_get_temp(&temp);
368 	if (err)
369 		return err;
370 
371 	if (verbose)
372 		pr_notice("temp %d\n", temp);
373 
374 	*t = temp;
375 	return 0;
376 }
377 
378 static int acerhdf_bind(struct thermal_zone_device *thermal,
379 			struct thermal_cooling_device *cdev)
380 {
381 	/* if the cooling device is the one from acerhdf bind it */
382 	if (cdev != cl_dev)
383 		return 0;
384 
385 	if (thermal_zone_bind_cooling_device(thermal, 0, cdev,
386 			THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
387 			THERMAL_WEIGHT_DEFAULT)) {
388 		pr_err("error binding cooling dev\n");
389 		return -EINVAL;
390 	}
391 	return 0;
392 }
393 
394 static int acerhdf_unbind(struct thermal_zone_device *thermal,
395 			  struct thermal_cooling_device *cdev)
396 {
397 	if (cdev != cl_dev)
398 		return 0;
399 
400 	if (thermal_zone_unbind_cooling_device(thermal, 0, cdev)) {
401 		pr_err("error unbinding cooling dev\n");
402 		return -EINVAL;
403 	}
404 	return 0;
405 }
406 
407 static inline void acerhdf_revert_to_bios_mode(void)
408 {
409 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
410 	kernelmode = 0;
411 	if (thz_dev)
412 		thz_dev->polling_delay = 0;
413 	pr_notice("kernel mode fan control OFF\n");
414 }
415 static inline void acerhdf_enable_kernelmode(void)
416 {
417 	kernelmode = 1;
418 
419 	thz_dev->polling_delay = interval*1000;
420 	thermal_zone_device_update(thz_dev, THERMAL_EVENT_UNSPECIFIED);
421 	pr_notice("kernel mode fan control ON\n");
422 }
423 
424 static int acerhdf_get_mode(struct thermal_zone_device *thermal,
425 			    enum thermal_device_mode *mode)
426 {
427 	if (verbose)
428 		pr_notice("kernel mode fan control %d\n", kernelmode);
429 
430 	*mode = (kernelmode) ? THERMAL_DEVICE_ENABLED
431 			     : THERMAL_DEVICE_DISABLED;
432 
433 	return 0;
434 }
435 
436 /*
437  * set operation mode;
438  * enabled: the thermal layer of the kernel takes care about
439  *          the temperature and the fan.
440  * disabled: the BIOS takes control of the fan.
441  */
442 static int acerhdf_set_mode(struct thermal_zone_device *thermal,
443 			    enum thermal_device_mode mode)
444 {
445 	if (mode == THERMAL_DEVICE_DISABLED && kernelmode)
446 		acerhdf_revert_to_bios_mode();
447 	else if (mode == THERMAL_DEVICE_ENABLED && !kernelmode)
448 		acerhdf_enable_kernelmode();
449 
450 	return 0;
451 }
452 
453 static int acerhdf_get_trip_type(struct thermal_zone_device *thermal, int trip,
454 				 enum thermal_trip_type *type)
455 {
456 	if (trip == 0)
457 		*type = THERMAL_TRIP_ACTIVE;
458 	else if (trip == 1)
459 		*type = THERMAL_TRIP_CRITICAL;
460 	else
461 		return -EINVAL;
462 
463 	return 0;
464 }
465 
466 static int acerhdf_get_trip_hyst(struct thermal_zone_device *thermal, int trip,
467 				 int *temp)
468 {
469 	if (trip != 0)
470 		return -EINVAL;
471 
472 	*temp = fanon - fanoff;
473 
474 	return 0;
475 }
476 
477 static int acerhdf_get_trip_temp(struct thermal_zone_device *thermal, int trip,
478 				 int *temp)
479 {
480 	if (trip == 0)
481 		*temp = fanon;
482 	else if (trip == 1)
483 		*temp = ACERHDF_TEMP_CRIT;
484 	else
485 		return -EINVAL;
486 
487 	return 0;
488 }
489 
490 static int acerhdf_get_crit_temp(struct thermal_zone_device *thermal,
491 				 int *temperature)
492 {
493 	*temperature = ACERHDF_TEMP_CRIT;
494 	return 0;
495 }
496 
497 /* bind callback functions to thermalzone */
498 static struct thermal_zone_device_ops acerhdf_dev_ops = {
499 	.bind = acerhdf_bind,
500 	.unbind = acerhdf_unbind,
501 	.get_temp = acerhdf_get_ec_temp,
502 	.get_mode = acerhdf_get_mode,
503 	.set_mode = acerhdf_set_mode,
504 	.get_trip_type = acerhdf_get_trip_type,
505 	.get_trip_hyst = acerhdf_get_trip_hyst,
506 	.get_trip_temp = acerhdf_get_trip_temp,
507 	.get_crit_temp = acerhdf_get_crit_temp,
508 };
509 
510 
511 /*
512  * cooling device callback functions
513  * get maximal fan cooling state
514  */
515 static int acerhdf_get_max_state(struct thermal_cooling_device *cdev,
516 				 unsigned long *state)
517 {
518 	*state = 1;
519 
520 	return 0;
521 }
522 
523 static int acerhdf_get_cur_state(struct thermal_cooling_device *cdev,
524 				 unsigned long *state)
525 {
526 	int err = 0, tmp;
527 
528 	err = acerhdf_get_fanstate(&tmp);
529 	if (err)
530 		return err;
531 
532 	*state = (tmp == ACERHDF_FAN_AUTO) ? 1 : 0;
533 	return 0;
534 }
535 
536 /* change current fan state - is overwritten when running in kernel mode */
537 static int acerhdf_set_cur_state(struct thermal_cooling_device *cdev,
538 				 unsigned long state)
539 {
540 	int cur_temp, cur_state, err = 0;
541 
542 	if (!kernelmode)
543 		return 0;
544 
545 	err = acerhdf_get_temp(&cur_temp);
546 	if (err) {
547 		pr_err("error reading temperature, hand off control to BIOS\n");
548 		goto err_out;
549 	}
550 
551 	err = acerhdf_get_fanstate(&cur_state);
552 	if (err) {
553 		pr_err("error reading fan state, hand off control to BIOS\n");
554 		goto err_out;
555 	}
556 
557 	if (state == 0) {
558 		if (cur_state == ACERHDF_FAN_AUTO)
559 			acerhdf_change_fanstate(ACERHDF_FAN_OFF);
560 	} else {
561 		if (cur_state == ACERHDF_FAN_OFF)
562 			acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
563 	}
564 	return 0;
565 
566 err_out:
567 	acerhdf_revert_to_bios_mode();
568 	return -EINVAL;
569 }
570 
571 /* bind fan callbacks to fan device */
572 static const struct thermal_cooling_device_ops acerhdf_cooling_ops = {
573 	.get_max_state = acerhdf_get_max_state,
574 	.get_cur_state = acerhdf_get_cur_state,
575 	.set_cur_state = acerhdf_set_cur_state,
576 };
577 
578 /* suspend / resume functionality */
579 static int acerhdf_suspend(struct device *dev)
580 {
581 	if (kernelmode)
582 		acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
583 
584 	if (verbose)
585 		pr_notice("going suspend\n");
586 
587 	return 0;
588 }
589 
590 static int acerhdf_probe(struct platform_device *device)
591 {
592 	return 0;
593 }
594 
595 static int acerhdf_remove(struct platform_device *device)
596 {
597 	return 0;
598 }
599 
600 static const struct dev_pm_ops acerhdf_pm_ops = {
601 	.suspend = acerhdf_suspend,
602 	.freeze  = acerhdf_suspend,
603 };
604 
605 static struct platform_driver acerhdf_driver = {
606 	.driver = {
607 		.name  = "acerhdf",
608 		.pm    = &acerhdf_pm_ops,
609 	},
610 	.probe = acerhdf_probe,
611 	.remove = acerhdf_remove,
612 };
613 
614 /* checks if str begins with start */
615 static int str_starts_with(const char *str, const char *start)
616 {
617 	unsigned long str_len = 0, start_len = 0;
618 
619 	str_len = strlen(str);
620 	start_len = strlen(start);
621 
622 	if (str_len >= start_len &&
623 			!strncmp(str, start, start_len))
624 		return 1;
625 
626 	return 0;
627 }
628 
629 /* check hardware */
630 static int __init acerhdf_check_hardware(void)
631 {
632 	char const *vendor, *version, *product;
633 	const struct bios_settings *bt = NULL;
634 	int found = 0;
635 
636 	/* get BIOS data */
637 	vendor  = dmi_get_system_info(DMI_SYS_VENDOR);
638 	version = dmi_get_system_info(DMI_BIOS_VERSION);
639 	product = dmi_get_system_info(DMI_PRODUCT_NAME);
640 
641 	if (!vendor || !version || !product) {
642 		pr_err("error getting hardware information\n");
643 		return -EINVAL;
644 	}
645 
646 	pr_info("Acer Aspire One Fan driver, v.%s\n", DRV_VER);
647 
648 	if (list_supported) {
649 		pr_info("List of supported Manufacturer/Model/BIOS:\n");
650 		pr_info("---------------------------------------------------\n");
651 		for (bt = bios_tbl; bt->vendor[0]; bt++) {
652 			pr_info("%-13s | %-17s | %-10s\n", bt->vendor,
653 				bt->product, bt->version);
654 		}
655 		pr_info("---------------------------------------------------\n");
656 		return -ECANCELED;
657 	}
658 
659 	if (force_bios[0]) {
660 		version = force_bios;
661 		pr_info("forcing BIOS version: %s\n", version);
662 		kernelmode = 0;
663 	}
664 
665 	if (force_product[0]) {
666 		product = force_product;
667 		pr_info("forcing BIOS product: %s\n", product);
668 		kernelmode = 0;
669 	}
670 
671 	if (verbose)
672 		pr_info("BIOS info: %s %s, product: %s\n",
673 			vendor, version, product);
674 
675 	/* search BIOS version and vendor in BIOS settings table */
676 	for (bt = bios_tbl; bt->vendor[0]; bt++) {
677 		/*
678 		 * check if actual hardware BIOS vendor, product and version
679 		 * IDs start with the strings of BIOS table entry
680 		 */
681 		if (str_starts_with(vendor, bt->vendor) &&
682 				str_starts_with(product, bt->product) &&
683 				str_starts_with(version, bt->version)) {
684 			found = 1;
685 			break;
686 		}
687 	}
688 
689 	if (!found) {
690 		pr_err("unknown (unsupported) BIOS version %s/%s/%s, please report, aborting!\n",
691 		       vendor, product, version);
692 		return -EINVAL;
693 	}
694 
695 	/* Copy control settings from BIOS table before we free it. */
696 	ctrl_cfg.fanreg = bt->fanreg;
697 	ctrl_cfg.tempreg = bt->tempreg;
698 	memcpy(&ctrl_cfg.cmd, &bt->cmd, sizeof(struct fancmd));
699 	ctrl_cfg.mcmd_enable = bt->mcmd_enable;
700 
701 	/*
702 	 * if started with kernel mode off, prevent the kernel from switching
703 	 * off the fan
704 	 */
705 	if (!kernelmode) {
706 		pr_notice("Fan control off, to enable do:\n");
707 		pr_notice("echo -n \"enabled\" > /sys/class/thermal/thermal_zoneN/mode # N=0,1,2...\n");
708 	}
709 
710 	return 0;
711 }
712 
713 static int __init acerhdf_register_platform(void)
714 {
715 	int err = 0;
716 
717 	err = platform_driver_register(&acerhdf_driver);
718 	if (err)
719 		return err;
720 
721 	acerhdf_dev = platform_device_alloc("acerhdf", -1);
722 	if (!acerhdf_dev) {
723 		err = -ENOMEM;
724 		goto err_device_alloc;
725 	}
726 	err = platform_device_add(acerhdf_dev);
727 	if (err)
728 		goto err_device_add;
729 
730 	return 0;
731 
732 err_device_add:
733 	platform_device_put(acerhdf_dev);
734 err_device_alloc:
735 	platform_driver_unregister(&acerhdf_driver);
736 	return err;
737 }
738 
739 static void acerhdf_unregister_platform(void)
740 {
741 	platform_device_unregister(acerhdf_dev);
742 	platform_driver_unregister(&acerhdf_driver);
743 }
744 
745 static int __init acerhdf_register_thermal(void)
746 {
747 	cl_dev = thermal_cooling_device_register("acerhdf-fan", NULL,
748 						 &acerhdf_cooling_ops);
749 
750 	if (IS_ERR(cl_dev))
751 		return -EINVAL;
752 
753 	thz_dev = thermal_zone_device_register("acerhdf", 2, 0, NULL,
754 					      &acerhdf_dev_ops,
755 					      &acerhdf_zone_params, 0,
756 					      (kernelmode) ? interval*1000 : 0);
757 	if (IS_ERR(thz_dev))
758 		return -EINVAL;
759 
760 	if (strcmp(thz_dev->governor->name,
761 				acerhdf_zone_params.governor_name)) {
762 		pr_err("Didn't get thermal governor %s, perhaps not compiled into thermal subsystem.\n",
763 				acerhdf_zone_params.governor_name);
764 		return -EINVAL;
765 	}
766 
767 	return 0;
768 }
769 
770 static void acerhdf_unregister_thermal(void)
771 {
772 	if (cl_dev) {
773 		thermal_cooling_device_unregister(cl_dev);
774 		cl_dev = NULL;
775 	}
776 
777 	if (thz_dev) {
778 		thermal_zone_device_unregister(thz_dev);
779 		thz_dev = NULL;
780 	}
781 }
782 
783 static int __init acerhdf_init(void)
784 {
785 	int err = 0;
786 
787 	err = acerhdf_check_hardware();
788 	if (err)
789 		goto out_err;
790 
791 	err = acerhdf_register_platform();
792 	if (err)
793 		goto out_err;
794 
795 	err = acerhdf_register_thermal();
796 	if (err)
797 		goto err_unreg;
798 
799 	return 0;
800 
801 err_unreg:
802 	acerhdf_unregister_thermal();
803 	acerhdf_unregister_platform();
804 
805 out_err:
806 	return err;
807 }
808 
809 static void __exit acerhdf_exit(void)
810 {
811 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
812 	acerhdf_unregister_thermal();
813 	acerhdf_unregister_platform();
814 }
815 
816 MODULE_LICENSE("GPL");
817 MODULE_AUTHOR("Peter Feuerer");
818 MODULE_DESCRIPTION("Aspire One temperature and fan driver");
819 MODULE_ALIAS("dmi:*:*Acer*:pnAOA*:");
820 MODULE_ALIAS("dmi:*:*Acer*:pnAO751h*:");
821 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1410*:");
822 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1810*:");
823 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5755G:");
824 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1825PTZ:");
825 MODULE_ALIAS("dmi:*:*Acer*:pnAO521*:");
826 MODULE_ALIAS("dmi:*:*Acer*:pnAO531*:");
827 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5739G:");
828 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*One*753:");
829 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5315:");
830 MODULE_ALIAS("dmi:*:*Acer*:TravelMate*7730G:");
831 MODULE_ALIAS("dmi:*:*Acer*:TM8573T:");
832 MODULE_ALIAS("dmi:*:*Gateway*:pnAOA*:");
833 MODULE_ALIAS("dmi:*:*Gateway*:pnLT31*:");
834 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnAOA*:");
835 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOA*:");
836 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMU*:");
837 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnENBFT*:");
838 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMA*:");
839 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTVR46*:");
840 MODULE_ALIAS("dmi:*:*Acer*:pnExtensa 5420*:");
841 
842 module_init(acerhdf_init);
843 module_exit(acerhdf_exit);
844