xref: /openbmc/linux/drivers/platform/x86/acerhdf.c (revision 45fe9262)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * acerhdf - A driver which monitors the temperature
4  *           of the aspire one netbook, turns on/off the fan
5  *           as soon as the upper/lower threshold is reached.
6  *
7  * (C) 2009 - Peter Kaestle     peter (a) piie.net
8  *                              https://piie.net
9  *     2009 Borislav Petkov	bp (a) alien8.de
10  *
11  * Inspired by and many thanks to:
12  *  o acerfand   - Rachel Greenham
13  *  o acer_ec.pl - Michael Kurz     michi.kurz (at) googlemail.com
14  *               - Petr Tomasek     tomasek (#) etf,cuni,cz
15  *               - Carlos Corbacho  cathectic (at) gmail.com
16  *  o lkml       - Matthew Garrett
17  *               - Borislav Petkov
18  *               - Andreas Mohr
19  */
20 
21 #define pr_fmt(fmt) "acerhdf: " fmt
22 
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/dmi.h>
26 #include <linux/acpi.h>
27 #include <linux/thermal.h>
28 #include <linux/platform_device.h>
29 
30 /*
31  * The driver is started with "kernel mode off" by default. That means, the BIOS
32  * is still in control of the fan. In this mode the driver allows to read the
33  * temperature of the cpu and a userspace tool may take over control of the fan.
34  * If the driver is switched to "kernel mode" (e.g. via module parameter) the
35  * driver is in full control of the fan. If you want the module to be started in
36  * kernel mode by default, define the following:
37  */
38 #undef START_IN_KERNEL_MODE
39 
40 #define DRV_VER "0.7.0"
41 
42 /*
43  * According to the Atom N270 datasheet,
44  * (http://download.intel.com/design/processor/datashts/320032.pdf) the
45  * CPU's optimal operating limits denoted in junction temperature as
46  * measured by the on-die thermal monitor are within 0 <= Tj <= 90. So,
47  * assume 89°C is critical temperature.
48  */
49 #define ACERHDF_TEMP_CRIT 89000
50 #define ACERHDF_FAN_OFF 0
51 #define ACERHDF_FAN_AUTO 1
52 
53 /*
54  * No matter what value the user puts into the fanon variable, turn on the fan
55  * at 80 degree Celsius to prevent hardware damage
56  */
57 #define ACERHDF_MAX_FANON 80000
58 
59 /*
60  * Maximum interval between two temperature checks is 15 seconds, as the die
61  * can get hot really fast under heavy load (plus we shouldn't forget about
62  * possible impact of _external_ aggressive sources such as heaters, sun etc.)
63  */
64 #define ACERHDF_MAX_INTERVAL 15
65 
66 #ifdef START_IN_KERNEL_MODE
67 static int kernelmode = 1;
68 #else
69 static int kernelmode;
70 #endif
71 
72 static unsigned int interval = 10;
73 static unsigned int fanon = 60000;
74 static unsigned int fanoff = 53000;
75 static unsigned int verbose;
76 static unsigned int list_supported;
77 static unsigned int fanstate = ACERHDF_FAN_AUTO;
78 static char force_bios[16];
79 static char force_product[16];
80 static unsigned int prev_interval;
81 static struct thermal_zone_device *thz_dev;
82 static struct thermal_cooling_device *cl_dev;
83 static struct platform_device *acerhdf_dev;
84 
85 module_param(kernelmode, uint, 0);
86 MODULE_PARM_DESC(kernelmode, "Kernel mode fan control on / off");
87 module_param(fanon, uint, 0600);
88 MODULE_PARM_DESC(fanon, "Turn the fan on above this temperature");
89 module_param(fanoff, uint, 0600);
90 MODULE_PARM_DESC(fanoff, "Turn the fan off below this temperature");
91 module_param(verbose, uint, 0600);
92 MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");
93 module_param(list_supported, uint, 0600);
94 MODULE_PARM_DESC(list_supported, "List supported models and BIOS versions");
95 module_param_string(force_bios, force_bios, 16, 0);
96 MODULE_PARM_DESC(force_bios, "Pretend system has this known supported BIOS version");
97 module_param_string(force_product, force_product, 16, 0);
98 MODULE_PARM_DESC(force_product, "Pretend system is this known supported model");
99 
100 /*
101  * cmd_off: to switch the fan completely off and check if the fan is off
102  *	cmd_auto: to set the BIOS in control of the fan. The BIOS regulates then
103  *		the fan speed depending on the temperature
104  */
105 struct fancmd {
106 	u8 cmd_off;
107 	u8 cmd_auto;
108 };
109 
110 struct manualcmd {
111 	u8 mreg;
112 	u8 moff;
113 };
114 
115 /* default register and command to disable fan in manual mode */
116 static const struct manualcmd mcmd = {
117 	.mreg = 0x94,
118 	.moff = 0xff,
119 };
120 
121 /* BIOS settings - only used during probe */
122 struct bios_settings {
123 	const char *vendor;
124 	const char *product;
125 	const char *version;
126 	u8 fanreg;
127 	u8 tempreg;
128 	struct fancmd cmd;
129 	int mcmd_enable;
130 };
131 
132 /* This could be a daughter struct in the above, but not worth the redirect */
133 struct ctrl_settings {
134 	u8 fanreg;
135 	u8 tempreg;
136 	struct fancmd cmd;
137 	int mcmd_enable;
138 };
139 
140 static struct ctrl_settings ctrl_cfg __read_mostly;
141 
142 /* Register addresses and values for different BIOS versions */
143 static const struct bios_settings bios_tbl[] __initconst = {
144 	/* AOA110 */
145 	{"Acer", "AOA110", "v0.3109", 0x55, 0x58, {0x1f, 0x00}, 0},
146 	{"Acer", "AOA110", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
147 	{"Acer", "AOA110", "v0.3301", 0x55, 0x58, {0xaf, 0x00}, 0},
148 	{"Acer", "AOA110", "v0.3304", 0x55, 0x58, {0xaf, 0x00}, 0},
149 	{"Acer", "AOA110", "v0.3305", 0x55, 0x58, {0xaf, 0x00}, 0},
150 	{"Acer", "AOA110", "v0.3307", 0x55, 0x58, {0xaf, 0x00}, 0},
151 	{"Acer", "AOA110", "v0.3308", 0x55, 0x58, {0x21, 0x00}, 0},
152 	{"Acer", "AOA110", "v0.3309", 0x55, 0x58, {0x21, 0x00}, 0},
153 	{"Acer", "AOA110", "v0.3310", 0x55, 0x58, {0x21, 0x00}, 0},
154 	/* AOA150 */
155 	{"Acer", "AOA150", "v0.3114", 0x55, 0x58, {0x1f, 0x00}, 0},
156 	{"Acer", "AOA150", "v0.3301", 0x55, 0x58, {0x20, 0x00}, 0},
157 	{"Acer", "AOA150", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
158 	{"Acer", "AOA150", "v0.3305", 0x55, 0x58, {0x20, 0x00}, 0},
159 	{"Acer", "AOA150", "v0.3307", 0x55, 0x58, {0x20, 0x00}, 0},
160 	{"Acer", "AOA150", "v0.3308", 0x55, 0x58, {0x20, 0x00}, 0},
161 	{"Acer", "AOA150", "v0.3309", 0x55, 0x58, {0x20, 0x00}, 0},
162 	{"Acer", "AOA150", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
163 	/* LT1005u */
164 	{"Acer", "LT-10Q", "v0.3310", 0x55, 0x58, {0x20, 0x00}, 0},
165 	/* Acer 1410 */
166 	{"Acer", "Aspire 1410", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
167 	{"Acer", "Aspire 1410", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
168 	{"Acer", "Aspire 1410", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
169 	{"Acer", "Aspire 1410", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
170 	{"Acer", "Aspire 1410", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
171 	{"Acer", "Aspire 1410", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
172 	{"Acer", "Aspire 1410", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
173 	{"Acer", "Aspire 1410", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
174 	{"Acer", "Aspire 1410", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
175 	{"Acer", "Aspire 1410", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
176 	{"Acer", "Aspire 1410", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
177 	/* Acer 1810xx */
178 	{"Acer", "Aspire 1810TZ", "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
179 	{"Acer", "Aspire 1810T",  "v0.3108", 0x55, 0x58, {0x9e, 0x00}, 0},
180 	{"Acer", "Aspire 1810TZ", "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
181 	{"Acer", "Aspire 1810T",  "v0.3113", 0x55, 0x58, {0x9e, 0x00}, 0},
182 	{"Acer", "Aspire 1810TZ", "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
183 	{"Acer", "Aspire 1810T",  "v0.3115", 0x55, 0x58, {0x9e, 0x00}, 0},
184 	{"Acer", "Aspire 1810TZ", "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
185 	{"Acer", "Aspire 1810T",  "v0.3117", 0x55, 0x58, {0x9e, 0x00}, 0},
186 	{"Acer", "Aspire 1810TZ", "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
187 	{"Acer", "Aspire 1810T",  "v0.3119", 0x55, 0x58, {0x9e, 0x00}, 0},
188 	{"Acer", "Aspire 1810TZ", "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
189 	{"Acer", "Aspire 1810T",  "v0.3120", 0x55, 0x58, {0x9e, 0x00}, 0},
190 	{"Acer", "Aspire 1810TZ", "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
191 	{"Acer", "Aspire 1810T",  "v1.3204", 0x55, 0x58, {0x9e, 0x00}, 0},
192 	{"Acer", "Aspire 1810TZ", "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
193 	{"Acer", "Aspire 1810T",  "v1.3303", 0x55, 0x58, {0x9e, 0x00}, 0},
194 	{"Acer", "Aspire 1810TZ", "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
195 	{"Acer", "Aspire 1810T",  "v1.3308", 0x55, 0x58, {0x9e, 0x00}, 0},
196 	{"Acer", "Aspire 1810TZ", "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
197 	{"Acer", "Aspire 1810T",  "v1.3310", 0x55, 0x58, {0x9e, 0x00}, 0},
198 	{"Acer", "Aspire 1810TZ", "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
199 	{"Acer", "Aspire 1810T",  "v1.3314", 0x55, 0x58, {0x9e, 0x00}, 0},
200 	/* Acer 5755G */
201 	{"Acer", "Aspire 5755G",  "V1.20",   0xab, 0xb4, {0x00, 0x08}, 0},
202 	{"Acer", "Aspire 5755G",  "V1.21",   0xab, 0xb3, {0x00, 0x08}, 0},
203 	/* Acer 521 */
204 	{"Acer", "AO521", "V1.11", 0x55, 0x58, {0x1f, 0x00}, 0},
205 	/* Acer 531 */
206 	{"Acer", "AO531h", "v0.3104", 0x55, 0x58, {0x20, 0x00}, 0},
207 	{"Acer", "AO531h", "v0.3201", 0x55, 0x58, {0x20, 0x00}, 0},
208 	{"Acer", "AO531h", "v0.3304", 0x55, 0x58, {0x20, 0x00}, 0},
209 	/* Acer 751 */
210 	{"Acer", "AO751h", "V0.3206", 0x55, 0x58, {0x21, 0x00}, 0},
211 	{"Acer", "AO751h", "V0.3212", 0x55, 0x58, {0x21, 0x00}, 0},
212 	/* Acer 753 */
213 	{"Acer", "Aspire One 753", "V1.24", 0x93, 0xac, {0x14, 0x04}, 1},
214 	/* Acer 1825 */
215 	{"Acer", "Aspire 1825PTZ", "V1.3118", 0x55, 0x58, {0x9e, 0x00}, 0},
216 	{"Acer", "Aspire 1825PTZ", "V1.3127", 0x55, 0x58, {0x9e, 0x00}, 0},
217 	/* Acer Extensa 5420 */
218 	{"Acer", "Extensa 5420", "V1.17", 0x93, 0xac, {0x14, 0x04}, 1},
219 	/* Acer Aspire 5315 */
220 	{"Acer", "Aspire 5315", "V1.19", 0x93, 0xac, {0x14, 0x04}, 1},
221 	/* Acer Aspire 5739 */
222 	{"Acer", "Aspire 5739G", "V1.3311", 0x55, 0x58, {0x20, 0x00}, 0},
223 	/* Acer TravelMate 7730 */
224 	{"Acer", "TravelMate 7730G", "v0.3509", 0x55, 0x58, {0xaf, 0x00}, 0},
225 	/* Acer Aspire 7551 */
226 	{"Acer", "Aspire 7551", "V1.18", 0x93, 0xa8, {0x14, 0x04}, 1},
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 	{"Gateway", "LT31",   "v1.3307",  0x55, 0x58, {0x9e, 0x00}, 0},
237 	/* Packard Bell */
238 	{"Packard Bell", "DOA150",  "v0.3104",  0x55, 0x58, {0x21, 0x00}, 0},
239 	{"Packard Bell", "DOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
240 	{"Packard Bell", "AOA110",  "v0.3105",  0x55, 0x58, {0x21, 0x00}, 0},
241 	{"Packard Bell", "AOA150",  "v0.3105",  0x55, 0x58, {0x20, 0x00}, 0},
242 	{"Packard Bell", "ENBFT",   "V1.3118",  0x55, 0x58, {0x9e, 0x00}, 0},
243 	{"Packard Bell", "ENBFT",   "V1.3127",  0x55, 0x58, {0x9e, 0x00}, 0},
244 	{"Packard Bell", "DOTMU",   "v1.3303",  0x55, 0x58, {0x9e, 0x00}, 0},
245 	{"Packard Bell", "DOTMU",   "v0.3120",  0x55, 0x58, {0x9e, 0x00}, 0},
246 	{"Packard Bell", "DOTMU",   "v0.3108",  0x55, 0x58, {0x9e, 0x00}, 0},
247 	{"Packard Bell", "DOTMU",   "v0.3113",  0x55, 0x58, {0x9e, 0x00}, 0},
248 	{"Packard Bell", "DOTMU",   "v0.3115",  0x55, 0x58, {0x9e, 0x00}, 0},
249 	{"Packard Bell", "DOTMU",   "v0.3117",  0x55, 0x58, {0x9e, 0x00}, 0},
250 	{"Packard Bell", "DOTMU",   "v0.3119",  0x55, 0x58, {0x9e, 0x00}, 0},
251 	{"Packard Bell", "DOTMU",   "v1.3204",  0x55, 0x58, {0x9e, 0x00}, 0},
252 	{"Packard Bell", "DOTMA",   "v1.3201",  0x55, 0x58, {0x9e, 0x00}, 0},
253 	{"Packard Bell", "DOTMA",   "v1.3302",  0x55, 0x58, {0x9e, 0x00}, 0},
254 	{"Packard Bell", "DOTMA",   "v1.3303t", 0x55, 0x58, {0x9e, 0x00}, 0},
255 	{"Packard Bell", "DOTVR46", "v1.3308",  0x55, 0x58, {0x9e, 0x00}, 0},
256 	/* pewpew-terminator */
257 	{"", "", "", 0, 0, {0, 0}, 0}
258 };
259 
260 /*
261  * this struct is used to instruct thermal layer to use bang_bang instead of
262  * default governor for acerhdf
263  */
264 static struct thermal_zone_params acerhdf_zone_params = {
265 	.governor_name = "bang_bang",
266 };
267 
268 static int acerhdf_get_temp(int *temp)
269 {
270 	u8 read_temp;
271 
272 	if (ec_read(ctrl_cfg.tempreg, &read_temp))
273 		return -EINVAL;
274 
275 	*temp = read_temp * 1000;
276 
277 	return 0;
278 }
279 
280 static int acerhdf_get_fanstate(int *state)
281 {
282 	u8 fan;
283 
284 	if (ec_read(ctrl_cfg.fanreg, &fan))
285 		return -EINVAL;
286 
287 	if (fan != ctrl_cfg.cmd.cmd_off)
288 		*state = ACERHDF_FAN_AUTO;
289 	else
290 		*state = ACERHDF_FAN_OFF;
291 
292 	return 0;
293 }
294 
295 static void acerhdf_change_fanstate(int state)
296 {
297 	unsigned char cmd;
298 
299 	if (verbose)
300 		pr_notice("fan %s\n", state == ACERHDF_FAN_OFF ? "OFF" : "ON");
301 
302 	if ((state != ACERHDF_FAN_OFF) && (state != ACERHDF_FAN_AUTO)) {
303 		pr_err("invalid fan state %d requested, setting to auto!\n",
304 		       state);
305 		state = ACERHDF_FAN_AUTO;
306 	}
307 
308 	cmd = (state == ACERHDF_FAN_OFF) ? ctrl_cfg.cmd.cmd_off
309 					 : ctrl_cfg.cmd.cmd_auto;
310 	fanstate = state;
311 
312 	ec_write(ctrl_cfg.fanreg, cmd);
313 
314 	if (ctrl_cfg.mcmd_enable && state == ACERHDF_FAN_OFF) {
315 		if (verbose)
316 			pr_notice("turning off fan manually\n");
317 		ec_write(mcmd.mreg, mcmd.moff);
318 	}
319 }
320 
321 static void acerhdf_check_param(struct thermal_zone_device *thermal)
322 {
323 	if (fanon > ACERHDF_MAX_FANON) {
324 		pr_err("fanon temperature too high, set to %d\n",
325 		       ACERHDF_MAX_FANON);
326 		fanon = ACERHDF_MAX_FANON;
327 	}
328 
329 	if (kernelmode && prev_interval != interval) {
330 		if (interval > ACERHDF_MAX_INTERVAL) {
331 			pr_err("interval too high, set to %d\n",
332 			       ACERHDF_MAX_INTERVAL);
333 			interval = ACERHDF_MAX_INTERVAL;
334 		}
335 		if (verbose)
336 			pr_notice("interval changed to: %d\n", interval);
337 
338 		if (thermal)
339 			thermal->polling_delay = interval*1000;
340 
341 		prev_interval = interval;
342 	}
343 }
344 
345 /*
346  * This is the thermal zone callback which does the delayed polling of the fan
347  * state. We do check /sysfs-originating settings here in acerhdf_check_param()
348  * as late as the polling interval is since we can't do that in the respective
349  * accessors of the module parameters.
350  */
351 static int acerhdf_get_ec_temp(struct thermal_zone_device *thermal, int *t)
352 {
353 	int temp, err = 0;
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 
400 	pr_notice("kernel mode fan control OFF\n");
401 }
402 static inline void acerhdf_enable_kernelmode(void)
403 {
404 	kernelmode = 1;
405 
406 	pr_notice("kernel mode fan control ON\n");
407 }
408 
409 /*
410  * set operation mode;
411  * enabled: the thermal layer of the kernel takes care about
412  *          the temperature and the fan.
413  * disabled: the BIOS takes control of the fan.
414  */
415 static int acerhdf_change_mode(struct thermal_zone_device *thermal,
416 			       enum thermal_device_mode mode)
417 {
418 	if (mode == THERMAL_DEVICE_DISABLED && kernelmode)
419 		acerhdf_revert_to_bios_mode();
420 	else if (mode == THERMAL_DEVICE_ENABLED && !kernelmode)
421 		acerhdf_enable_kernelmode();
422 
423 	return 0;
424 }
425 
426 static int acerhdf_get_trip_type(struct thermal_zone_device *thermal, int trip,
427 				 enum thermal_trip_type *type)
428 {
429 	if (trip == 0)
430 		*type = THERMAL_TRIP_ACTIVE;
431 	else if (trip == 1)
432 		*type = THERMAL_TRIP_CRITICAL;
433 	else
434 		return -EINVAL;
435 
436 	return 0;
437 }
438 
439 static int acerhdf_get_trip_hyst(struct thermal_zone_device *thermal, int trip,
440 				 int *temp)
441 {
442 	if (trip != 0)
443 		return -EINVAL;
444 
445 	*temp = fanon - fanoff;
446 
447 	return 0;
448 }
449 
450 static int acerhdf_get_trip_temp(struct thermal_zone_device *thermal, int trip,
451 				 int *temp)
452 {
453 	if (trip == 0)
454 		*temp = fanon;
455 	else if (trip == 1)
456 		*temp = ACERHDF_TEMP_CRIT;
457 	else
458 		return -EINVAL;
459 
460 	return 0;
461 }
462 
463 static int acerhdf_get_crit_temp(struct thermal_zone_device *thermal,
464 				 int *temperature)
465 {
466 	*temperature = ACERHDF_TEMP_CRIT;
467 	return 0;
468 }
469 
470 /* bind callback functions to thermalzone */
471 static struct thermal_zone_device_ops acerhdf_dev_ops = {
472 	.bind = acerhdf_bind,
473 	.unbind = acerhdf_unbind,
474 	.get_temp = acerhdf_get_ec_temp,
475 	.change_mode = acerhdf_change_mode,
476 	.get_trip_type = acerhdf_get_trip_type,
477 	.get_trip_hyst = acerhdf_get_trip_hyst,
478 	.get_trip_temp = acerhdf_get_trip_temp,
479 	.get_crit_temp = acerhdf_get_crit_temp,
480 };
481 
482 
483 /*
484  * cooling device callback functions
485  * get maximal fan cooling state
486  */
487 static int acerhdf_get_max_state(struct thermal_cooling_device *cdev,
488 				 unsigned long *state)
489 {
490 	*state = 1;
491 
492 	return 0;
493 }
494 
495 static int acerhdf_get_cur_state(struct thermal_cooling_device *cdev,
496 				 unsigned long *state)
497 {
498 	int err = 0, tmp;
499 
500 	err = acerhdf_get_fanstate(&tmp);
501 	if (err)
502 		return err;
503 
504 	*state = (tmp == ACERHDF_FAN_AUTO) ? 1 : 0;
505 	return 0;
506 }
507 
508 /* change current fan state - is overwritten when running in kernel mode */
509 static int acerhdf_set_cur_state(struct thermal_cooling_device *cdev,
510 				 unsigned long state)
511 {
512 	int cur_temp, cur_state, err = 0;
513 
514 	if (!kernelmode)
515 		return 0;
516 
517 	err = acerhdf_get_temp(&cur_temp);
518 	if (err) {
519 		pr_err("error reading temperature, hand off control to BIOS\n");
520 		goto err_out;
521 	}
522 
523 	err = acerhdf_get_fanstate(&cur_state);
524 	if (err) {
525 		pr_err("error reading fan state, hand off control to BIOS\n");
526 		goto err_out;
527 	}
528 
529 	if (state == 0) {
530 		if (cur_state == ACERHDF_FAN_AUTO)
531 			acerhdf_change_fanstate(ACERHDF_FAN_OFF);
532 	} else {
533 		if (cur_state == ACERHDF_FAN_OFF)
534 			acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
535 	}
536 	return 0;
537 
538 err_out:
539 	acerhdf_revert_to_bios_mode();
540 	return -EINVAL;
541 }
542 
543 /* bind fan callbacks to fan device */
544 static const struct thermal_cooling_device_ops acerhdf_cooling_ops = {
545 	.get_max_state = acerhdf_get_max_state,
546 	.get_cur_state = acerhdf_get_cur_state,
547 	.set_cur_state = acerhdf_set_cur_state,
548 };
549 
550 /* suspend / resume functionality */
551 static int acerhdf_suspend(struct device *dev)
552 {
553 	if (kernelmode)
554 		acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
555 
556 	if (verbose)
557 		pr_notice("going suspend\n");
558 
559 	return 0;
560 }
561 
562 static int acerhdf_probe(struct platform_device *device)
563 {
564 	return 0;
565 }
566 
567 static int acerhdf_remove(struct platform_device *device)
568 {
569 	return 0;
570 }
571 
572 static const struct dev_pm_ops acerhdf_pm_ops = {
573 	.suspend = acerhdf_suspend,
574 	.freeze  = acerhdf_suspend,
575 };
576 
577 static struct platform_driver acerhdf_driver = {
578 	.driver = {
579 		.name  = "acerhdf",
580 		.pm    = &acerhdf_pm_ops,
581 	},
582 	.probe = acerhdf_probe,
583 	.remove = acerhdf_remove,
584 };
585 
586 /* checks if str begins with start */
587 static int str_starts_with(const char *str, const char *start)
588 {
589 	unsigned long str_len = 0, start_len = 0;
590 
591 	str_len = strlen(str);
592 	start_len = strlen(start);
593 
594 	if (str_len >= start_len &&
595 			!strncmp(str, start, start_len))
596 		return 1;
597 
598 	return 0;
599 }
600 
601 /* check hardware */
602 static int __init acerhdf_check_hardware(void)
603 {
604 	char const *vendor, *version, *product;
605 	const struct bios_settings *bt = NULL;
606 	int found = 0;
607 
608 	/* get BIOS data */
609 	vendor  = dmi_get_system_info(DMI_SYS_VENDOR);
610 	version = dmi_get_system_info(DMI_BIOS_VERSION);
611 	product = dmi_get_system_info(DMI_PRODUCT_NAME);
612 
613 	if (!vendor || !version || !product) {
614 		pr_err("error getting hardware information\n");
615 		return -EINVAL;
616 	}
617 
618 	pr_info("Acer Aspire One Fan driver, v.%s\n", DRV_VER);
619 
620 	if (list_supported) {
621 		pr_info("List of supported Manufacturer/Model/BIOS:\n");
622 		pr_info("---------------------------------------------------\n");
623 		for (bt = bios_tbl; bt->vendor[0]; bt++) {
624 			pr_info("%-13s | %-17s | %-10s\n", bt->vendor,
625 				bt->product, bt->version);
626 		}
627 		pr_info("---------------------------------------------------\n");
628 		return -ECANCELED;
629 	}
630 
631 	if (force_bios[0]) {
632 		version = force_bios;
633 		pr_info("forcing BIOS version: %s\n", version);
634 		kernelmode = 0;
635 	}
636 
637 	if (force_product[0]) {
638 		product = force_product;
639 		pr_info("forcing BIOS product: %s\n", product);
640 		kernelmode = 0;
641 	}
642 
643 	if (verbose)
644 		pr_info("BIOS info: %s %s, product: %s\n",
645 			vendor, version, product);
646 
647 	/* search BIOS version and vendor in BIOS settings table */
648 	for (bt = bios_tbl; bt->vendor[0]; bt++) {
649 		/*
650 		 * check if actual hardware BIOS vendor, product and version
651 		 * IDs start with the strings of BIOS table entry
652 		 */
653 		if (str_starts_with(vendor, bt->vendor) &&
654 				str_starts_with(product, bt->product) &&
655 				str_starts_with(version, bt->version)) {
656 			found = 1;
657 			break;
658 		}
659 	}
660 
661 	if (!found) {
662 		pr_err("unknown (unsupported) BIOS version %s/%s/%s, please report, aborting!\n",
663 		       vendor, product, version);
664 		return -EINVAL;
665 	}
666 
667 	/* Copy control settings from BIOS table before we free it. */
668 	ctrl_cfg.fanreg = bt->fanreg;
669 	ctrl_cfg.tempreg = bt->tempreg;
670 	memcpy(&ctrl_cfg.cmd, &bt->cmd, sizeof(struct fancmd));
671 	ctrl_cfg.mcmd_enable = bt->mcmd_enable;
672 
673 	/*
674 	 * if started with kernel mode off, prevent the kernel from switching
675 	 * off the fan
676 	 */
677 	if (!kernelmode) {
678 		pr_notice("Fan control off, to enable do:\n");
679 		pr_notice("echo -n \"enabled\" > /sys/class/thermal/thermal_zoneN/mode # N=0,1,2...\n");
680 	}
681 
682 	return 0;
683 }
684 
685 static int __init acerhdf_register_platform(void)
686 {
687 	int err = 0;
688 
689 	err = platform_driver_register(&acerhdf_driver);
690 	if (err)
691 		return err;
692 
693 	acerhdf_dev = platform_device_alloc("acerhdf", -1);
694 	if (!acerhdf_dev) {
695 		err = -ENOMEM;
696 		goto err_device_alloc;
697 	}
698 	err = platform_device_add(acerhdf_dev);
699 	if (err)
700 		goto err_device_add;
701 
702 	return 0;
703 
704 err_device_add:
705 	platform_device_put(acerhdf_dev);
706 err_device_alloc:
707 	platform_driver_unregister(&acerhdf_driver);
708 	return err;
709 }
710 
711 static void acerhdf_unregister_platform(void)
712 {
713 	platform_device_unregister(acerhdf_dev);
714 	platform_driver_unregister(&acerhdf_driver);
715 }
716 
717 static int __init acerhdf_register_thermal(void)
718 {
719 	int ret;
720 
721 	cl_dev = thermal_cooling_device_register("acerhdf-fan", NULL,
722 						 &acerhdf_cooling_ops);
723 
724 	if (IS_ERR(cl_dev))
725 		return -EINVAL;
726 
727 	thz_dev = thermal_zone_device_register("acerhdf", 2, 0, NULL,
728 					      &acerhdf_dev_ops,
729 					      &acerhdf_zone_params, 0,
730 					      (kernelmode) ? interval*1000 : 0);
731 	if (IS_ERR(thz_dev))
732 		return -EINVAL;
733 
734 	if (kernelmode)
735 		ret = thermal_zone_device_enable(thz_dev);
736 	else
737 		ret = thermal_zone_device_disable(thz_dev);
738 	if (ret)
739 		return ret;
740 
741 	if (strcmp(thz_dev->governor->name,
742 				acerhdf_zone_params.governor_name)) {
743 		pr_err("Didn't get thermal governor %s, perhaps not compiled into thermal subsystem.\n",
744 				acerhdf_zone_params.governor_name);
745 		return -EINVAL;
746 	}
747 
748 	return 0;
749 }
750 
751 static void acerhdf_unregister_thermal(void)
752 {
753 	if (cl_dev) {
754 		thermal_cooling_device_unregister(cl_dev);
755 		cl_dev = NULL;
756 	}
757 
758 	if (thz_dev) {
759 		thermal_zone_device_unregister(thz_dev);
760 		thz_dev = NULL;
761 	}
762 }
763 
764 static int __init acerhdf_init(void)
765 {
766 	int err = 0;
767 
768 	err = acerhdf_check_hardware();
769 	if (err)
770 		goto out_err;
771 
772 	err = acerhdf_register_platform();
773 	if (err)
774 		goto out_err;
775 
776 	err = acerhdf_register_thermal();
777 	if (err)
778 		goto err_unreg;
779 
780 	return 0;
781 
782 err_unreg:
783 	acerhdf_unregister_thermal();
784 	acerhdf_unregister_platform();
785 
786 out_err:
787 	return err;
788 }
789 
790 static void __exit acerhdf_exit(void)
791 {
792 	acerhdf_change_fanstate(ACERHDF_FAN_AUTO);
793 	acerhdf_unregister_thermal();
794 	acerhdf_unregister_platform();
795 }
796 
797 MODULE_LICENSE("GPL");
798 MODULE_AUTHOR("Peter Kaestle");
799 MODULE_DESCRIPTION("Aspire One temperature and fan driver");
800 MODULE_ALIAS("dmi:*:*Acer*:pnAOA*:");
801 MODULE_ALIAS("dmi:*:*Acer*:pnAO751h*:");
802 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1410*:");
803 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1810*:");
804 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5755G:");
805 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*1825PTZ:");
806 MODULE_ALIAS("dmi:*:*Acer*:pnAO521*:");
807 MODULE_ALIAS("dmi:*:*Acer*:pnAO531*:");
808 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5739G:");
809 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*One*753:");
810 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*5315:");
811 MODULE_ALIAS("dmi:*:*Acer*:TravelMate*7730G:");
812 MODULE_ALIAS("dmi:*:*Acer*:pnAspire*7551:");
813 MODULE_ALIAS("dmi:*:*Acer*:TM8573T:");
814 MODULE_ALIAS("dmi:*:*Gateway*:pnAOA*:");
815 MODULE_ALIAS("dmi:*:*Gateway*:pnLT31*:");
816 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnAOA*:");
817 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOA*:");
818 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMU*:");
819 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnENBFT*:");
820 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTMA*:");
821 MODULE_ALIAS("dmi:*:*Packard*Bell*:pnDOTVR46*:");
822 MODULE_ALIAS("dmi:*:*Acer*:pnExtensa*5420*:");
823 
824 module_init(acerhdf_init);
825 module_exit(acerhdf_exit);
826 
827 static int interval_set_uint(const char *val, const struct kernel_param *kp)
828 {
829 	int ret;
830 
831 	ret = param_set_uint(val, kp);
832 	if (ret)
833 		return ret;
834 
835 	acerhdf_check_param(thz_dev);
836 
837 	return 0;
838 }
839 
840 static const struct kernel_param_ops interval_ops = {
841 	.set = interval_set_uint,
842 	.get = param_get_uint,
843 };
844 
845 module_param_cb(interval, &interval_ops, &interval, 0600);
846 MODULE_PARM_DESC(interval, "Polling interval of temperature check");
847