xref: /openbmc/linux/drivers/acpi/thermal.c (revision 64c70b1c)
1 /*
2  *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  *
25  *  This driver fully implements the ACPI thermal policy as described in the
26  *  ACPI 2.0 Specification.
27  *
28  *  TBD: 1. Implement passive cooling hysteresis.
29  *       2. Enhance passive cooling (CPU) states/limit interface to support
30  *          concepts of 'multiple limiters', upper/lower limits, etc.
31  *
32  */
33 
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/init.h>
37 #include <linux/types.h>
38 #include <linux/proc_fs.h>
39 #include <linux/timer.h>
40 #include <linux/jiffies.h>
41 #include <linux/kmod.h>
42 #include <linux/seq_file.h>
43 #include <asm/uaccess.h>
44 
45 #include <acpi/acpi_bus.h>
46 #include <acpi/acpi_drivers.h>
47 
48 #define ACPI_THERMAL_COMPONENT		0x04000000
49 #define ACPI_THERMAL_CLASS		"thermal_zone"
50 #define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
51 #define ACPI_THERMAL_FILE_STATE		"state"
52 #define ACPI_THERMAL_FILE_TEMPERATURE	"temperature"
53 #define ACPI_THERMAL_FILE_TRIP_POINTS	"trip_points"
54 #define ACPI_THERMAL_FILE_COOLING_MODE	"cooling_mode"
55 #define ACPI_THERMAL_FILE_POLLING_FREQ	"polling_frequency"
56 #define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
57 #define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
58 #define ACPI_THERMAL_NOTIFY_DEVICES	0x82
59 #define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
60 #define ACPI_THERMAL_NOTIFY_HOT		0xF1
61 #define ACPI_THERMAL_MODE_ACTIVE	0x00
62 #define ACPI_THERMAL_PATH_POWEROFF	"/sbin/poweroff"
63 
64 #define ACPI_THERMAL_MAX_ACTIVE	10
65 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
66 
67 #define KELVIN_TO_CELSIUS(t)    (long)(((long)t-2732>=0) ? ((long)t-2732+5)/10 : ((long)t-2732-5)/10)
68 #define CELSIUS_TO_KELVIN(t)	((t+273)*10)
69 
70 #define _COMPONENT		ACPI_THERMAL_COMPONENT
71 ACPI_MODULE_NAME("thermal");
72 
73 MODULE_AUTHOR("Paul Diefenbaugh");
74 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
75 MODULE_LICENSE("GPL");
76 
77 static int tzp;
78 module_param(tzp, int, 0);
79 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.\n");
80 
81 static int acpi_thermal_add(struct acpi_device *device);
82 static int acpi_thermal_remove(struct acpi_device *device, int type);
83 static int acpi_thermal_resume(struct acpi_device *device);
84 static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file);
85 static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file);
86 static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file);
87 static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file);
88 static ssize_t acpi_thermal_write_cooling_mode(struct file *,
89 					       const char __user *, size_t,
90 					       loff_t *);
91 static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file);
92 static ssize_t acpi_thermal_write_polling(struct file *, const char __user *,
93 					  size_t, loff_t *);
94 
95 static struct acpi_driver acpi_thermal_driver = {
96 	.name = "thermal",
97 	.class = ACPI_THERMAL_CLASS,
98 	.ids = ACPI_THERMAL_HID,
99 	.ops = {
100 		.add = acpi_thermal_add,
101 		.remove = acpi_thermal_remove,
102 		.resume = acpi_thermal_resume,
103 		},
104 };
105 
106 struct acpi_thermal_state {
107 	u8 critical:1;
108 	u8 hot:1;
109 	u8 passive:1;
110 	u8 active:1;
111 	u8 reserved:4;
112 	int active_index;
113 };
114 
115 struct acpi_thermal_state_flags {
116 	u8 valid:1;
117 	u8 enabled:1;
118 	u8 reserved:6;
119 };
120 
121 struct acpi_thermal_critical {
122 	struct acpi_thermal_state_flags flags;
123 	unsigned long temperature;
124 };
125 
126 struct acpi_thermal_hot {
127 	struct acpi_thermal_state_flags flags;
128 	unsigned long temperature;
129 };
130 
131 struct acpi_thermal_passive {
132 	struct acpi_thermal_state_flags flags;
133 	unsigned long temperature;
134 	unsigned long tc1;
135 	unsigned long tc2;
136 	unsigned long tsp;
137 	struct acpi_handle_list devices;
138 };
139 
140 struct acpi_thermal_active {
141 	struct acpi_thermal_state_flags flags;
142 	unsigned long temperature;
143 	struct acpi_handle_list devices;
144 };
145 
146 struct acpi_thermal_trips {
147 	struct acpi_thermal_critical critical;
148 	struct acpi_thermal_hot hot;
149 	struct acpi_thermal_passive passive;
150 	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
151 };
152 
153 struct acpi_thermal_flags {
154 	u8 cooling_mode:1;	/* _SCP */
155 	u8 devices:1;		/* _TZD */
156 	u8 reserved:6;
157 };
158 
159 struct acpi_thermal {
160 	struct acpi_device * device;
161 	acpi_bus_id name;
162 	unsigned long temperature;
163 	unsigned long last_temperature;
164 	unsigned long polling_frequency;
165 	volatile u8 zombie;
166 	struct acpi_thermal_flags flags;
167 	struct acpi_thermal_state state;
168 	struct acpi_thermal_trips trips;
169 	struct acpi_handle_list devices;
170 	struct timer_list timer;
171 };
172 
173 static const struct file_operations acpi_thermal_state_fops = {
174 	.open = acpi_thermal_state_open_fs,
175 	.read = seq_read,
176 	.llseek = seq_lseek,
177 	.release = single_release,
178 };
179 
180 static const struct file_operations acpi_thermal_temp_fops = {
181 	.open = acpi_thermal_temp_open_fs,
182 	.read = seq_read,
183 	.llseek = seq_lseek,
184 	.release = single_release,
185 };
186 
187 static const struct file_operations acpi_thermal_trip_fops = {
188 	.open = acpi_thermal_trip_open_fs,
189 	.read = seq_read,
190 	.llseek = seq_lseek,
191 	.release = single_release,
192 };
193 
194 static const struct file_operations acpi_thermal_cooling_fops = {
195 	.open = acpi_thermal_cooling_open_fs,
196 	.read = seq_read,
197 	.write = acpi_thermal_write_cooling_mode,
198 	.llseek = seq_lseek,
199 	.release = single_release,
200 };
201 
202 static const struct file_operations acpi_thermal_polling_fops = {
203 	.open = acpi_thermal_polling_open_fs,
204 	.read = seq_read,
205 	.write = acpi_thermal_write_polling,
206 	.llseek = seq_lseek,
207 	.release = single_release,
208 };
209 
210 /* --------------------------------------------------------------------------
211                              Thermal Zone Management
212    -------------------------------------------------------------------------- */
213 
214 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
215 {
216 	acpi_status status = AE_OK;
217 
218 
219 	if (!tz)
220 		return -EINVAL;
221 
222 	tz->last_temperature = tz->temperature;
223 
224 	status =
225 	    acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tz->temperature);
226 	if (ACPI_FAILURE(status))
227 		return -ENODEV;
228 
229 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
230 			  tz->temperature));
231 
232 	return 0;
233 }
234 
235 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
236 {
237 	acpi_status status = AE_OK;
238 
239 
240 	if (!tz)
241 		return -EINVAL;
242 
243 	status =
244 	    acpi_evaluate_integer(tz->device->handle, "_TZP", NULL,
245 				  &tz->polling_frequency);
246 	if (ACPI_FAILURE(status))
247 		return -ENODEV;
248 
249 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
250 			  tz->polling_frequency));
251 
252 	return 0;
253 }
254 
255 static int acpi_thermal_set_polling(struct acpi_thermal *tz, int seconds)
256 {
257 
258 	if (!tz)
259 		return -EINVAL;
260 
261 	tz->polling_frequency = seconds * 10;	/* Convert value to deci-seconds */
262 
263 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
264 			  "Polling frequency set to %lu seconds\n",
265 			  tz->polling_frequency/10));
266 
267 	return 0;
268 }
269 
270 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
271 {
272 	acpi_status status = AE_OK;
273 	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
274 	struct acpi_object_list arg_list = { 1, &arg0 };
275 	acpi_handle handle = NULL;
276 
277 
278 	if (!tz)
279 		return -EINVAL;
280 
281 	status = acpi_get_handle(tz->device->handle, "_SCP", &handle);
282 	if (ACPI_FAILURE(status)) {
283 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
284 		return -ENODEV;
285 	}
286 
287 	arg0.integer.value = mode;
288 
289 	status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
290 	if (ACPI_FAILURE(status))
291 		return -ENODEV;
292 
293 	return 0;
294 }
295 
296 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
297 {
298 	acpi_status status = AE_OK;
299 	int i = 0;
300 
301 
302 	if (!tz)
303 		return -EINVAL;
304 
305 	/* Critical Shutdown (required) */
306 
307 	status = acpi_evaluate_integer(tz->device->handle, "_CRT", NULL,
308 				       &tz->trips.critical.temperature);
309 	if (ACPI_FAILURE(status)) {
310 		tz->trips.critical.flags.valid = 0;
311 		ACPI_EXCEPTION((AE_INFO, status, "No critical threshold"));
312 		return -ENODEV;
313 	} else {
314 		tz->trips.critical.flags.valid = 1;
315 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
316 				  "Found critical threshold [%lu]\n",
317 				  tz->trips.critical.temperature));
318 	}
319 
320 	/* Critical Sleep (optional) */
321 
322 	status =
323 	    acpi_evaluate_integer(tz->device->handle, "_HOT", NULL,
324 				  &tz->trips.hot.temperature);
325 	if (ACPI_FAILURE(status)) {
326 		tz->trips.hot.flags.valid = 0;
327 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No hot threshold\n"));
328 	} else {
329 		tz->trips.hot.flags.valid = 1;
330 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found hot threshold [%lu]\n",
331 				  tz->trips.hot.temperature));
332 	}
333 
334 	/* Passive: Processors (optional) */
335 
336 	status =
337 	    acpi_evaluate_integer(tz->device->handle, "_PSV", NULL,
338 				  &tz->trips.passive.temperature);
339 	if (ACPI_FAILURE(status)) {
340 		tz->trips.passive.flags.valid = 0;
341 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No passive threshold\n"));
342 	} else {
343 		tz->trips.passive.flags.valid = 1;
344 
345 		status =
346 		    acpi_evaluate_integer(tz->device->handle, "_TC1", NULL,
347 					  &tz->trips.passive.tc1);
348 		if (ACPI_FAILURE(status))
349 			tz->trips.passive.flags.valid = 0;
350 
351 		status =
352 		    acpi_evaluate_integer(tz->device->handle, "_TC2", NULL,
353 					  &tz->trips.passive.tc2);
354 		if (ACPI_FAILURE(status))
355 			tz->trips.passive.flags.valid = 0;
356 
357 		status =
358 		    acpi_evaluate_integer(tz->device->handle, "_TSP", NULL,
359 					  &tz->trips.passive.tsp);
360 		if (ACPI_FAILURE(status))
361 			tz->trips.passive.flags.valid = 0;
362 
363 		status =
364 		    acpi_evaluate_reference(tz->device->handle, "_PSL", NULL,
365 					    &tz->trips.passive.devices);
366 		if (ACPI_FAILURE(status))
367 			tz->trips.passive.flags.valid = 0;
368 
369 		if (!tz->trips.passive.flags.valid)
370 			printk(KERN_WARNING PREFIX "Invalid passive threshold\n");
371 		else
372 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
373 					  "Found passive threshold [%lu]\n",
374 					  tz->trips.passive.temperature));
375 	}
376 
377 	/* Active: Fans, etc. (optional) */
378 
379 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
380 
381 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
382 
383 		status =
384 		    acpi_evaluate_integer(tz->device->handle, name, NULL,
385 					  &tz->trips.active[i].temperature);
386 		if (ACPI_FAILURE(status))
387 			break;
388 
389 		name[2] = 'L';
390 		status =
391 		    acpi_evaluate_reference(tz->device->handle, name, NULL,
392 					    &tz->trips.active[i].devices);
393 		if (ACPI_SUCCESS(status)) {
394 			tz->trips.active[i].flags.valid = 1;
395 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
396 					  "Found active threshold [%d]:[%lu]\n",
397 					  i, tz->trips.active[i].temperature));
398 		} else
399 			ACPI_EXCEPTION((AE_INFO, status,
400 					"Invalid active threshold [%d]", i));
401 	}
402 
403 	return 0;
404 }
405 
406 static int acpi_thermal_get_devices(struct acpi_thermal *tz)
407 {
408 	acpi_status status = AE_OK;
409 
410 
411 	if (!tz)
412 		return -EINVAL;
413 
414 	status =
415 	    acpi_evaluate_reference(tz->device->handle, "_TZD", NULL, &tz->devices);
416 	if (ACPI_FAILURE(status))
417 		return -ENODEV;
418 
419 	return 0;
420 }
421 
422 static int acpi_thermal_call_usermode(char *path)
423 {
424 	char *argv[2] = { NULL, NULL };
425 	char *envp[3] = { NULL, NULL, NULL };
426 
427 
428 	if (!path)
429 		return -EINVAL;
430 
431 	argv[0] = path;
432 
433 	/* minimal command environment */
434 	envp[0] = "HOME=/";
435 	envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
436 
437 	call_usermodehelper(argv[0], argv, envp, 0);
438 
439 	return 0;
440 }
441 
442 static int acpi_thermal_critical(struct acpi_thermal *tz)
443 {
444 	if (!tz || !tz->trips.critical.flags.valid)
445 		return -EINVAL;
446 
447 	if (tz->temperature >= tz->trips.critical.temperature) {
448 		printk(KERN_WARNING PREFIX "Critical trip point\n");
449 		tz->trips.critical.flags.enabled = 1;
450 	} else if (tz->trips.critical.flags.enabled)
451 		tz->trips.critical.flags.enabled = 0;
452 
453 	printk(KERN_EMERG
454 	       "Critical temperature reached (%ld C), shutting down.\n",
455 	       KELVIN_TO_CELSIUS(tz->temperature));
456 	acpi_bus_generate_event(tz->device, ACPI_THERMAL_NOTIFY_CRITICAL,
457 				tz->trips.critical.flags.enabled);
458 
459 	acpi_thermal_call_usermode(ACPI_THERMAL_PATH_POWEROFF);
460 
461 	return 0;
462 }
463 
464 static int acpi_thermal_hot(struct acpi_thermal *tz)
465 {
466 	if (!tz || !tz->trips.hot.flags.valid)
467 		return -EINVAL;
468 
469 	if (tz->temperature >= tz->trips.hot.temperature) {
470 		printk(KERN_WARNING PREFIX "Hot trip point\n");
471 		tz->trips.hot.flags.enabled = 1;
472 	} else if (tz->trips.hot.flags.enabled)
473 		tz->trips.hot.flags.enabled = 0;
474 
475 	acpi_bus_generate_event(tz->device, ACPI_THERMAL_NOTIFY_HOT,
476 				tz->trips.hot.flags.enabled);
477 
478 	/* TBD: Call user-mode "sleep(S4)" function */
479 
480 	return 0;
481 }
482 
483 static void acpi_thermal_passive(struct acpi_thermal *tz)
484 {
485 	int result = 1;
486 	struct acpi_thermal_passive *passive = NULL;
487 	int trend = 0;
488 	int i = 0;
489 
490 
491 	if (!tz || !tz->trips.passive.flags.valid)
492 		return;
493 
494 	passive = &(tz->trips.passive);
495 
496 	/*
497 	 * Above Trip?
498 	 * -----------
499 	 * Calculate the thermal trend (using the passive cooling equation)
500 	 * and modify the performance limit for all passive cooling devices
501 	 * accordingly.  Note that we assume symmetry.
502 	 */
503 	if (tz->temperature >= passive->temperature) {
504 		trend =
505 		    (passive->tc1 * (tz->temperature - tz->last_temperature)) +
506 		    (passive->tc2 * (tz->temperature - passive->temperature));
507 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
508 				  "trend[%d]=(tc1[%lu]*(tmp[%lu]-last[%lu]))+(tc2[%lu]*(tmp[%lu]-psv[%lu]))\n",
509 				  trend, passive->tc1, tz->temperature,
510 				  tz->last_temperature, passive->tc2,
511 				  tz->temperature, passive->temperature));
512 		passive->flags.enabled = 1;
513 		/* Heating up? */
514 		if (trend > 0)
515 			for (i = 0; i < passive->devices.count; i++)
516 				acpi_processor_set_thermal_limit(passive->
517 								 devices.
518 								 handles[i],
519 								 ACPI_PROCESSOR_LIMIT_INCREMENT);
520 		/* Cooling off? */
521 		else if (trend < 0) {
522 			for (i = 0; i < passive->devices.count; i++)
523 				/*
524 				 * assume that we are on highest
525 				 * freq/lowest thrott and can leave
526 				 * passive mode, even in error case
527 				 */
528 				if (!acpi_processor_set_thermal_limit
529 				    (passive->devices.handles[i],
530 				     ACPI_PROCESSOR_LIMIT_DECREMENT))
531 					result = 0;
532 			/*
533 			 * Leave cooling mode, even if the temp might
534 			 * higher than trip point This is because some
535 			 * machines might have long thermal polling
536 			 * frequencies (tsp) defined. We will fall back
537 			 * into passive mode in next cycle (probably quicker)
538 			 */
539 			if (result) {
540 				passive->flags.enabled = 0;
541 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
542 						  "Disabling passive cooling, still above threshold,"
543 						  " but we are cooling down\n"));
544 			}
545 		}
546 		return;
547 	}
548 
549 	/*
550 	 * Below Trip?
551 	 * -----------
552 	 * Implement passive cooling hysteresis to slowly increase performance
553 	 * and avoid thrashing around the passive trip point.  Note that we
554 	 * assume symmetry.
555 	 */
556 	if (!passive->flags.enabled)
557 		return;
558 	for (i = 0; i < passive->devices.count; i++)
559 		if (!acpi_processor_set_thermal_limit
560 		    (passive->devices.handles[i],
561 		     ACPI_PROCESSOR_LIMIT_DECREMENT))
562 			result = 0;
563 	if (result) {
564 		passive->flags.enabled = 0;
565 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
566 				  "Disabling passive cooling (zone is cool)\n"));
567 	}
568 }
569 
570 static void acpi_thermal_active(struct acpi_thermal *tz)
571 {
572 	int result = 0;
573 	struct acpi_thermal_active *active = NULL;
574 	int i = 0;
575 	int j = 0;
576 	unsigned long maxtemp = 0;
577 
578 
579 	if (!tz)
580 		return;
581 
582 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
583 		active = &(tz->trips.active[i]);
584 		if (!active || !active->flags.valid)
585 			break;
586 		if (tz->temperature >= active->temperature) {
587 			/*
588 			 * Above Threshold?
589 			 * ----------------
590 			 * If not already enabled, turn ON all cooling devices
591 			 * associated with this active threshold.
592 			 */
593 			if (active->temperature > maxtemp)
594 				tz->state.active_index = i;
595 			maxtemp = active->temperature;
596 			if (active->flags.enabled)
597 				continue;
598 			for (j = 0; j < active->devices.count; j++) {
599 				result =
600 				    acpi_bus_set_power(active->devices.
601 						       handles[j],
602 						       ACPI_STATE_D0);
603 				if (result) {
604 					printk(KERN_WARNING PREFIX
605 						      "Unable to turn cooling device [%p] 'on'\n",
606 						      active->devices.
607 						      handles[j]);
608 					continue;
609 				}
610 				active->flags.enabled = 1;
611 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
612 						  "Cooling device [%p] now 'on'\n",
613 						  active->devices.handles[j]));
614 			}
615 			continue;
616 		}
617 		if (!active->flags.enabled)
618 			continue;
619 		/*
620 		 * Below Threshold?
621 		 * ----------------
622 		 * Turn OFF all cooling devices associated with this
623 		 * threshold.
624 		 */
625 		for (j = 0; j < active->devices.count; j++) {
626 			result = acpi_bus_set_power(active->devices.handles[j],
627 						    ACPI_STATE_D3);
628 			if (result) {
629 				printk(KERN_WARNING PREFIX
630 					      "Unable to turn cooling device [%p] 'off'\n",
631 					      active->devices.handles[j]);
632 				continue;
633 			}
634 			active->flags.enabled = 0;
635 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
636 					  "Cooling device [%p] now 'off'\n",
637 					  active->devices.handles[j]));
638 		}
639 	}
640 }
641 
642 static void acpi_thermal_check(void *context);
643 
644 static void acpi_thermal_run(unsigned long data)
645 {
646 	struct acpi_thermal *tz = (struct acpi_thermal *)data;
647 	if (!tz->zombie)
648 		acpi_os_execute(OSL_GPE_HANDLER, acpi_thermal_check, (void *)data);
649 }
650 
651 static void acpi_thermal_check(void *data)
652 {
653 	int result = 0;
654 	struct acpi_thermal *tz = data;
655 	unsigned long sleep_time = 0;
656 	int i = 0;
657 	struct acpi_thermal_state state;
658 
659 
660 	if (!tz) {
661 		printk(KERN_ERR PREFIX "Invalid (NULL) context\n");
662 		return;
663 	}
664 
665 	state = tz->state;
666 
667 	result = acpi_thermal_get_temperature(tz);
668 	if (result)
669 		return;
670 
671 	memset(&tz->state, 0, sizeof(tz->state));
672 
673 	/*
674 	 * Check Trip Points
675 	 * -----------------
676 	 * Compare the current temperature to the trip point values to see
677 	 * if we've entered one of the thermal policy states.  Note that
678 	 * this function determines when a state is entered, but the
679 	 * individual policy decides when it is exited (e.g. hysteresis).
680 	 */
681 	if (tz->trips.critical.flags.valid)
682 		state.critical |=
683 		    (tz->temperature >= tz->trips.critical.temperature);
684 	if (tz->trips.hot.flags.valid)
685 		state.hot |= (tz->temperature >= tz->trips.hot.temperature);
686 	if (tz->trips.passive.flags.valid)
687 		state.passive |=
688 		    (tz->temperature >= tz->trips.passive.temperature);
689 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
690 		if (tz->trips.active[i].flags.valid)
691 			state.active |=
692 			    (tz->temperature >=
693 			     tz->trips.active[i].temperature);
694 
695 	/*
696 	 * Invoke Policy
697 	 * -------------
698 	 * Separated from the above check to allow individual policy to
699 	 * determine when to exit a given state.
700 	 */
701 	if (state.critical)
702 		acpi_thermal_critical(tz);
703 	if (state.hot)
704 		acpi_thermal_hot(tz);
705 	if (state.passive)
706 		acpi_thermal_passive(tz);
707 	if (state.active)
708 		acpi_thermal_active(tz);
709 
710 	/*
711 	 * Calculate State
712 	 * ---------------
713 	 * Again, separated from the above two to allow independent policy
714 	 * decisions.
715 	 */
716 	tz->state.critical = tz->trips.critical.flags.enabled;
717 	tz->state.hot = tz->trips.hot.flags.enabled;
718 	tz->state.passive = tz->trips.passive.flags.enabled;
719 	tz->state.active = 0;
720 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
721 		tz->state.active |= tz->trips.active[i].flags.enabled;
722 
723 	/*
724 	 * Calculate Sleep Time
725 	 * --------------------
726 	 * If we're in the passive state, use _TSP's value.  Otherwise
727 	 * use the default polling frequency (e.g. _TZP).  If no polling
728 	 * frequency is specified then we'll wait forever (at least until
729 	 * a thermal event occurs).  Note that _TSP and _TZD values are
730 	 * given in 1/10th seconds (we must covert to milliseconds).
731 	 */
732 	if (tz->state.passive)
733 		sleep_time = tz->trips.passive.tsp * 100;
734 	else if (tz->polling_frequency > 0)
735 		sleep_time = tz->polling_frequency * 100;
736 
737 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s: temperature[%lu] sleep[%lu]\n",
738 			  tz->name, tz->temperature, sleep_time));
739 
740 	/*
741 	 * Schedule Next Poll
742 	 * ------------------
743 	 */
744 	if (!sleep_time) {
745 		if (timer_pending(&(tz->timer)))
746 			del_timer(&(tz->timer));
747 	} else {
748 		if (timer_pending(&(tz->timer)))
749 			mod_timer(&(tz->timer),
750 					jiffies + (HZ * sleep_time) / 1000);
751 		else {
752 			tz->timer.data = (unsigned long)tz;
753 			tz->timer.function = acpi_thermal_run;
754 			tz->timer.expires = jiffies + (HZ * sleep_time) / 1000;
755 			add_timer(&(tz->timer));
756 		}
757 	}
758 
759 	return;
760 }
761 
762 /* --------------------------------------------------------------------------
763                               FS Interface (/proc)
764    -------------------------------------------------------------------------- */
765 
766 static struct proc_dir_entry *acpi_thermal_dir;
767 
768 static int acpi_thermal_state_seq_show(struct seq_file *seq, void *offset)
769 {
770 	struct acpi_thermal *tz = seq->private;
771 
772 
773 	if (!tz)
774 		goto end;
775 
776 	seq_puts(seq, "state:                   ");
777 
778 	if (!tz->state.critical && !tz->state.hot && !tz->state.passive
779 	    && !tz->state.active)
780 		seq_puts(seq, "ok\n");
781 	else {
782 		if (tz->state.critical)
783 			seq_puts(seq, "critical ");
784 		if (tz->state.hot)
785 			seq_puts(seq, "hot ");
786 		if (tz->state.passive)
787 			seq_puts(seq, "passive ");
788 		if (tz->state.active)
789 			seq_printf(seq, "active[%d]", tz->state.active_index);
790 		seq_puts(seq, "\n");
791 	}
792 
793       end:
794 	return 0;
795 }
796 
797 static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file)
798 {
799 	return single_open(file, acpi_thermal_state_seq_show, PDE(inode)->data);
800 }
801 
802 static int acpi_thermal_temp_seq_show(struct seq_file *seq, void *offset)
803 {
804 	int result = 0;
805 	struct acpi_thermal *tz = seq->private;
806 
807 
808 	if (!tz)
809 		goto end;
810 
811 	result = acpi_thermal_get_temperature(tz);
812 	if (result)
813 		goto end;
814 
815 	seq_printf(seq, "temperature:             %ld C\n",
816 		   KELVIN_TO_CELSIUS(tz->temperature));
817 
818       end:
819 	return 0;
820 }
821 
822 static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file)
823 {
824 	return single_open(file, acpi_thermal_temp_seq_show, PDE(inode)->data);
825 }
826 
827 static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset)
828 {
829 	struct acpi_thermal *tz = seq->private;
830 	struct acpi_device *device;
831 	acpi_status status;
832 
833 	int i = 0;
834 	int j = 0;
835 
836 
837 	if (!tz)
838 		goto end;
839 
840 	if (tz->trips.critical.flags.valid)
841 		seq_printf(seq, "critical (S5):           %ld C\n",
842 			   KELVIN_TO_CELSIUS(tz->trips.critical.temperature));
843 
844 	if (tz->trips.hot.flags.valid)
845 		seq_printf(seq, "hot (S4):                %ld C\n",
846 			   KELVIN_TO_CELSIUS(tz->trips.hot.temperature));
847 
848 	if (tz->trips.passive.flags.valid) {
849 		seq_printf(seq,
850 			   "passive:                 %ld C: tc1=%lu tc2=%lu tsp=%lu devices=",
851 			   KELVIN_TO_CELSIUS(tz->trips.passive.temperature),
852 			   tz->trips.passive.tc1, tz->trips.passive.tc2,
853 			   tz->trips.passive.tsp);
854 		for (j = 0; j < tz->trips.passive.devices.count; j++) {
855 			status = acpi_bus_get_device(tz->trips.passive.devices.
856 						     handles[j], &device);
857 			seq_printf(seq, "%4.4s ", status ? "" :
858 				   acpi_device_bid(device));
859 		}
860 		seq_puts(seq, "\n");
861 	}
862 
863 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
864 		if (!(tz->trips.active[i].flags.valid))
865 			break;
866 		seq_printf(seq, "active[%d]:               %ld C: devices=",
867 			   i,
868 			   KELVIN_TO_CELSIUS(tz->trips.active[i].temperature));
869 		for (j = 0; j < tz->trips.active[i].devices.count; j++){
870 			status = acpi_bus_get_device(tz->trips.active[i].
871 						     devices.handles[j],
872 						     &device);
873 			seq_printf(seq, "%4.4s ", status ? "" :
874 				   acpi_device_bid(device));
875 		}
876 		seq_puts(seq, "\n");
877 	}
878 
879       end:
880 	return 0;
881 }
882 
883 static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file)
884 {
885 	return single_open(file, acpi_thermal_trip_seq_show, PDE(inode)->data);
886 }
887 
888 static int acpi_thermal_cooling_seq_show(struct seq_file *seq, void *offset)
889 {
890 	struct acpi_thermal *tz = seq->private;
891 
892 
893 	if (!tz)
894 		goto end;
895 
896 	if (!tz->flags.cooling_mode)
897 		seq_puts(seq, "<setting not supported>\n");
898 	else
899 		seq_puts(seq, "0 - Active; 1 - Passive\n");
900 
901       end:
902 	return 0;
903 }
904 
905 static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file)
906 {
907 	return single_open(file, acpi_thermal_cooling_seq_show,
908 			   PDE(inode)->data);
909 }
910 
911 static ssize_t
912 acpi_thermal_write_cooling_mode(struct file *file,
913 				const char __user * buffer,
914 				size_t count, loff_t * ppos)
915 {
916 	struct seq_file *m = file->private_data;
917 	struct acpi_thermal *tz = m->private;
918 	int result = 0;
919 	char mode_string[12] = { '\0' };
920 
921 
922 	if (!tz || (count > sizeof(mode_string) - 1))
923 		return -EINVAL;
924 
925 	if (!tz->flags.cooling_mode)
926 		return -ENODEV;
927 
928 	if (copy_from_user(mode_string, buffer, count))
929 		return -EFAULT;
930 
931 	mode_string[count] = '\0';
932 
933 	result = acpi_thermal_set_cooling_mode(tz,
934 					       simple_strtoul(mode_string, NULL,
935 							      0));
936 	if (result)
937 		return result;
938 
939 	acpi_thermal_check(tz);
940 
941 	return count;
942 }
943 
944 static int acpi_thermal_polling_seq_show(struct seq_file *seq, void *offset)
945 {
946 	struct acpi_thermal *tz = seq->private;
947 
948 
949 	if (!tz)
950 		goto end;
951 
952 	if (!tz->polling_frequency) {
953 		seq_puts(seq, "<polling disabled>\n");
954 		goto end;
955 	}
956 
957 	seq_printf(seq, "polling frequency:       %lu seconds\n",
958 		   (tz->polling_frequency / 10));
959 
960       end:
961 	return 0;
962 }
963 
964 static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file)
965 {
966 	return single_open(file, acpi_thermal_polling_seq_show,
967 			   PDE(inode)->data);
968 }
969 
970 static ssize_t
971 acpi_thermal_write_polling(struct file *file,
972 			   const char __user * buffer,
973 			   size_t count, loff_t * ppos)
974 {
975 	struct seq_file *m = file->private_data;
976 	struct acpi_thermal *tz = m->private;
977 	int result = 0;
978 	char polling_string[12] = { '\0' };
979 	int seconds = 0;
980 
981 
982 	if (!tz || (count > sizeof(polling_string) - 1))
983 		return -EINVAL;
984 
985 	if (copy_from_user(polling_string, buffer, count))
986 		return -EFAULT;
987 
988 	polling_string[count] = '\0';
989 
990 	seconds = simple_strtoul(polling_string, NULL, 0);
991 
992 	result = acpi_thermal_set_polling(tz, seconds);
993 	if (result)
994 		return result;
995 
996 	acpi_thermal_check(tz);
997 
998 	return count;
999 }
1000 
1001 static int acpi_thermal_add_fs(struct acpi_device *device)
1002 {
1003 	struct proc_dir_entry *entry = NULL;
1004 
1005 
1006 	if (!acpi_device_dir(device)) {
1007 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
1008 						     acpi_thermal_dir);
1009 		if (!acpi_device_dir(device))
1010 			return -ENODEV;
1011 		acpi_device_dir(device)->owner = THIS_MODULE;
1012 	}
1013 
1014 	/* 'state' [R] */
1015 	entry = create_proc_entry(ACPI_THERMAL_FILE_STATE,
1016 				  S_IRUGO, acpi_device_dir(device));
1017 	if (!entry)
1018 		return -ENODEV;
1019 	else {
1020 		entry->proc_fops = &acpi_thermal_state_fops;
1021 		entry->data = acpi_driver_data(device);
1022 		entry->owner = THIS_MODULE;
1023 	}
1024 
1025 	/* 'temperature' [R] */
1026 	entry = create_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
1027 				  S_IRUGO, acpi_device_dir(device));
1028 	if (!entry)
1029 		return -ENODEV;
1030 	else {
1031 		entry->proc_fops = &acpi_thermal_temp_fops;
1032 		entry->data = acpi_driver_data(device);
1033 		entry->owner = THIS_MODULE;
1034 	}
1035 
1036 	/* 'trip_points' [R/W] */
1037 	entry = create_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
1038 				  S_IFREG | S_IRUGO | S_IWUSR,
1039 				  acpi_device_dir(device));
1040 	if (!entry)
1041 		return -ENODEV;
1042 	else {
1043 		entry->proc_fops = &acpi_thermal_trip_fops;
1044 		entry->data = acpi_driver_data(device);
1045 		entry->owner = THIS_MODULE;
1046 	}
1047 
1048 	/* 'cooling_mode' [R/W] */
1049 	entry = create_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
1050 				  S_IFREG | S_IRUGO | S_IWUSR,
1051 				  acpi_device_dir(device));
1052 	if (!entry)
1053 		return -ENODEV;
1054 	else {
1055 		entry->proc_fops = &acpi_thermal_cooling_fops;
1056 		entry->data = acpi_driver_data(device);
1057 		entry->owner = THIS_MODULE;
1058 	}
1059 
1060 	/* 'polling_frequency' [R/W] */
1061 	entry = create_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
1062 				  S_IFREG | S_IRUGO | S_IWUSR,
1063 				  acpi_device_dir(device));
1064 	if (!entry)
1065 		return -ENODEV;
1066 	else {
1067 		entry->proc_fops = &acpi_thermal_polling_fops;
1068 		entry->data = acpi_driver_data(device);
1069 		entry->owner = THIS_MODULE;
1070 	}
1071 
1072 	return 0;
1073 }
1074 
1075 static int acpi_thermal_remove_fs(struct acpi_device *device)
1076 {
1077 
1078 	if (acpi_device_dir(device)) {
1079 		remove_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
1080 				  acpi_device_dir(device));
1081 		remove_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
1082 				  acpi_device_dir(device));
1083 		remove_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
1084 				  acpi_device_dir(device));
1085 		remove_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
1086 				  acpi_device_dir(device));
1087 		remove_proc_entry(ACPI_THERMAL_FILE_STATE,
1088 				  acpi_device_dir(device));
1089 		remove_proc_entry(acpi_device_bid(device), acpi_thermal_dir);
1090 		acpi_device_dir(device) = NULL;
1091 	}
1092 
1093 	return 0;
1094 }
1095 
1096 /* --------------------------------------------------------------------------
1097                                  Driver Interface
1098    -------------------------------------------------------------------------- */
1099 
1100 static void acpi_thermal_notify(acpi_handle handle, u32 event, void *data)
1101 {
1102 	struct acpi_thermal *tz = data;
1103 	struct acpi_device *device = NULL;
1104 
1105 
1106 	if (!tz)
1107 		return;
1108 
1109 	device = tz->device;
1110 
1111 	switch (event) {
1112 	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
1113 		acpi_thermal_check(tz);
1114 		break;
1115 	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
1116 		acpi_thermal_get_trip_points(tz);
1117 		acpi_thermal_check(tz);
1118 		acpi_bus_generate_event(device, event, 0);
1119 		break;
1120 	case ACPI_THERMAL_NOTIFY_DEVICES:
1121 		if (tz->flags.devices)
1122 			acpi_thermal_get_devices(tz);
1123 		acpi_bus_generate_event(device, event, 0);
1124 		break;
1125 	default:
1126 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1127 				  "Unsupported event [0x%x]\n", event));
1128 		break;
1129 	}
1130 
1131 	return;
1132 }
1133 
1134 static int acpi_thermal_get_info(struct acpi_thermal *tz)
1135 {
1136 	int result = 0;
1137 
1138 
1139 	if (!tz)
1140 		return -EINVAL;
1141 
1142 	/* Get temperature [_TMP] (required) */
1143 	result = acpi_thermal_get_temperature(tz);
1144 	if (result)
1145 		return result;
1146 
1147 	/* Get trip points [_CRT, _PSV, etc.] (required) */
1148 	result = acpi_thermal_get_trip_points(tz);
1149 	if (result)
1150 		return result;
1151 
1152 	/* Set the cooling mode [_SCP] to active cooling (default) */
1153 	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
1154 	if (!result)
1155 		tz->flags.cooling_mode = 1;
1156 
1157 	/* Get default polling frequency [_TZP] (optional) */
1158 	if (tzp)
1159 		tz->polling_frequency = tzp;
1160 	else
1161 		acpi_thermal_get_polling_frequency(tz);
1162 
1163 	/* Get devices in this thermal zone [_TZD] (optional) */
1164 	result = acpi_thermal_get_devices(tz);
1165 	if (!result)
1166 		tz->flags.devices = 1;
1167 
1168 	return 0;
1169 }
1170 
1171 static int acpi_thermal_add(struct acpi_device *device)
1172 {
1173 	int result = 0;
1174 	acpi_status status = AE_OK;
1175 	struct acpi_thermal *tz = NULL;
1176 
1177 
1178 	if (!device)
1179 		return -EINVAL;
1180 
1181 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1182 	if (!tz)
1183 		return -ENOMEM;
1184 
1185 	tz->device = device;
1186 	strcpy(tz->name, device->pnp.bus_id);
1187 	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1188 	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1189 	acpi_driver_data(device) = tz;
1190 
1191 	result = acpi_thermal_get_info(tz);
1192 	if (result)
1193 		goto end;
1194 
1195 	result = acpi_thermal_add_fs(device);
1196 	if (result)
1197 		goto end;
1198 
1199 	init_timer(&tz->timer);
1200 
1201 	acpi_thermal_check(tz);
1202 
1203 	status = acpi_install_notify_handler(device->handle,
1204 					     ACPI_DEVICE_NOTIFY,
1205 					     acpi_thermal_notify, tz);
1206 	if (ACPI_FAILURE(status)) {
1207 		result = -ENODEV;
1208 		goto end;
1209 	}
1210 
1211 	printk(KERN_INFO PREFIX "%s [%s] (%ld C)\n",
1212 	       acpi_device_name(device), acpi_device_bid(device),
1213 	       KELVIN_TO_CELSIUS(tz->temperature));
1214 
1215       end:
1216 	if (result) {
1217 		acpi_thermal_remove_fs(device);
1218 		kfree(tz);
1219 	}
1220 
1221 	return result;
1222 }
1223 
1224 static int acpi_thermal_remove(struct acpi_device *device, int type)
1225 {
1226 	acpi_status status = AE_OK;
1227 	struct acpi_thermal *tz = NULL;
1228 
1229 
1230 	if (!device || !acpi_driver_data(device))
1231 		return -EINVAL;
1232 
1233 	tz = acpi_driver_data(device);
1234 
1235 	/* avoid timer adding new defer task */
1236 	tz->zombie = 1;
1237 	/* wait for running timer (on other CPUs) finish */
1238 	del_timer_sync(&(tz->timer));
1239 	/* synchronize deferred task */
1240 	acpi_os_wait_events_complete(NULL);
1241 	/* deferred task may reinsert timer */
1242 	del_timer_sync(&(tz->timer));
1243 
1244 	status = acpi_remove_notify_handler(device->handle,
1245 					    ACPI_DEVICE_NOTIFY,
1246 					    acpi_thermal_notify);
1247 
1248 	/* Terminate policy */
1249 	if (tz->trips.passive.flags.valid && tz->trips.passive.flags.enabled) {
1250 		tz->trips.passive.flags.enabled = 0;
1251 		acpi_thermal_passive(tz);
1252 	}
1253 	if (tz->trips.active[0].flags.valid
1254 	    && tz->trips.active[0].flags.enabled) {
1255 		tz->trips.active[0].flags.enabled = 0;
1256 		acpi_thermal_active(tz);
1257 	}
1258 
1259 	acpi_thermal_remove_fs(device);
1260 
1261 	kfree(tz);
1262 	return 0;
1263 }
1264 
1265 static int acpi_thermal_resume(struct acpi_device *device)
1266 {
1267 	struct acpi_thermal *tz = NULL;
1268 	int i, j, power_state, result;
1269 
1270 
1271 	if (!device || !acpi_driver_data(device))
1272 		return -EINVAL;
1273 
1274 	tz = acpi_driver_data(device);
1275 
1276 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1277 		if (!(&tz->trips.active[i]))
1278 			break;
1279 		if (!tz->trips.active[i].flags.valid)
1280 			break;
1281 		tz->trips.active[i].flags.enabled = 1;
1282 		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1283 			result = acpi_bus_get_power(tz->trips.active[i].devices.
1284 			    handles[j], &power_state);
1285 			if (result || (power_state != ACPI_STATE_D0)) {
1286 				tz->trips.active[i].flags.enabled = 0;
1287 				break;
1288 			}
1289 		}
1290 		tz->state.active |= tz->trips.active[i].flags.enabled;
1291 	}
1292 
1293 	acpi_thermal_check(tz);
1294 
1295 	return AE_OK;
1296 }
1297 
1298 static int __init acpi_thermal_init(void)
1299 {
1300 	int result = 0;
1301 
1302 
1303 	acpi_thermal_dir = proc_mkdir(ACPI_THERMAL_CLASS, acpi_root_dir);
1304 	if (!acpi_thermal_dir)
1305 		return -ENODEV;
1306 	acpi_thermal_dir->owner = THIS_MODULE;
1307 
1308 	result = acpi_bus_register_driver(&acpi_thermal_driver);
1309 	if (result < 0) {
1310 		remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
1311 		return -ENODEV;
1312 	}
1313 
1314 	return 0;
1315 }
1316 
1317 static void __exit acpi_thermal_exit(void)
1318 {
1319 
1320 	acpi_bus_unregister_driver(&acpi_thermal_driver);
1321 
1322 	remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
1323 
1324 	return;
1325 }
1326 
1327 module_init(acpi_thermal_init);
1328 module_exit(acpi_thermal_exit);
1329