xref: /freebsd/sys/dev/acpica/acpi_powerres.c (revision 84bbfc32a3f47bd2e32741247afe516cbeff7789)
1 /*-
2  * Copyright (c) 2001 Michael Smith
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 #include "opt_acpi.h"
29 #include <sys/param.h>
30 #include <sys/kernel.h>
31 #include <sys/malloc.h>
32 #include <sys/bus.h>
33 
34 #include <contrib/dev/acpica/include/acpi.h>
35 #include <contrib/dev/acpica/include/accommon.h>
36 
37 #include <dev/acpica/acpivar.h>
38 
39 /*
40  * ACPI power resource management.
41  *
42  * Power resource behaviour is slightly complicated by the fact that
43  * a single power resource may provide power for more than one device.
44  * Thus, we must track the device(s) being powered by a given power
45  * resource, and only deactivate it when there are no powered devices.
46  *
47  * Note that this only manages resources for known devices.  There is an
48  * ugly case where we may turn off power to a device which is in use because
49  * we don't know that it depends on a given resource.  We should perhaps
50  * try to be smarter about this, but a more complete solution would involve
51  * scanning all of the ACPI namespace to find devices we're not currently
52  * aware of, and this raises questions about whether they should be left
53  * on, turned off, etc.
54  */
55 
56 static MALLOC_DEFINE(M_ACPIPWR, "acpipwr", "ACPI power resources");
57 
58 /* Hooks for the ACPI CA debugging infrastructure */
59 #define _COMPONENT	ACPI_POWERRES
60 ACPI_MODULE_NAME("POWERRES")
61 
62 /* Return values from _STA on a power resource */
63 #define ACPI_PWR_OFF	0
64 #define ACPI_PWR_ON	1
65 
66 /* A relationship between a power resource and a consumer. */
67 struct acpi_powerreference {
68     struct acpi_powerconsumer		*ar_consumer;
69     struct acpi_powerresource		*ar_resource;
70     TAILQ_ENTRY(acpi_powerreference)	ar_rlink; /* link on resource list */
71     TAILQ_ENTRY(acpi_powerreference)	ar_clink; /* link on consumer */
72 };
73 
74 /* A power-managed device. */
75 struct acpi_powerconsumer {
76     /* Device which is powered */
77     ACPI_HANDLE				ac_consumer;
78     int					ac_state;
79     TAILQ_ENTRY(acpi_powerconsumer)	ac_link;
80     TAILQ_HEAD(,acpi_powerreference)	ac_references;
81 };
82 
83 /* A power resource. */
84 struct acpi_powerresource {
85     TAILQ_ENTRY(acpi_powerresource)	ap_link;
86     TAILQ_HEAD(,acpi_powerreference)	ap_references;
87     ACPI_HANDLE				ap_resource;
88     UINT64				ap_systemlevel;
89     UINT64				ap_order;
90 };
91 
92 static TAILQ_HEAD(acpi_powerresource_list, acpi_powerresource)
93     acpi_powerresources = TAILQ_HEAD_INITIALIZER(acpi_powerresources);
94 static TAILQ_HEAD(acpi_powerconsumer_list, acpi_powerconsumer)
95     acpi_powerconsumers = TAILQ_HEAD_INITIALIZER(acpi_powerconsumers);
96 ACPI_SERIAL_DECL(powerres, "ACPI power resources");
97 
98 static ACPI_STATUS	acpi_pwr_register_consumer(ACPI_HANDLE consumer);
99 #ifdef notyet
100 static ACPI_STATUS	acpi_pwr_deregister_consumer(ACPI_HANDLE consumer);
101 #endif /* notyet */
102 static ACPI_STATUS	acpi_pwr_register_resource(ACPI_HANDLE res);
103 #ifdef notyet
104 static ACPI_STATUS	acpi_pwr_deregister_resource(ACPI_HANDLE res);
105 #endif /* notyet */
106 static void		acpi_pwr_reference_resource(ACPI_OBJECT *obj,
107 						    void *arg);
108 static int		acpi_pwr_dereference_resource(struct acpi_powerconsumer
109 			    *pc);
110 static ACPI_STATUS	acpi_pwr_switch_power(void);
111 static struct acpi_powerresource
112 			*acpi_pwr_find_resource(ACPI_HANDLE res);
113 static struct acpi_powerconsumer
114 			*acpi_pwr_find_consumer(ACPI_HANDLE consumer);
115 
116 /*
117  * Register a power resource.
118  *
119  * It's OK to call this if we already know about the resource.
120  */
121 static ACPI_STATUS
acpi_pwr_register_resource(ACPI_HANDLE res)122 acpi_pwr_register_resource(ACPI_HANDLE res)
123 {
124     ACPI_STATUS			status;
125     ACPI_BUFFER			buf;
126     ACPI_OBJECT			*obj;
127     struct acpi_powerresource	*rp, *srp;
128 
129     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
130     ACPI_SERIAL_ASSERT(powerres);
131 
132     rp = NULL;
133     buf.Pointer = NULL;
134 
135     /* Look to see if we know about this resource */
136     if (acpi_pwr_find_resource(res) != NULL)
137 	return_ACPI_STATUS (AE_OK);		/* already know about it */
138 
139     /* Allocate a new resource */
140     if ((rp = malloc(sizeof(*rp), M_ACPIPWR, M_NOWAIT | M_ZERO)) == NULL) {
141 	status = AE_NO_MEMORY;
142 	goto out;
143     }
144     TAILQ_INIT(&rp->ap_references);
145     rp->ap_resource = res;
146 
147     /* Get the Power Resource object */
148     buf.Length = ACPI_ALLOCATE_BUFFER;
149     if (ACPI_FAILURE(status = AcpiEvaluateObject(res, NULL, NULL, &buf))) {
150 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "no power resource object\n"));
151 	goto out;
152     }
153     obj = buf.Pointer;
154     if (obj->Type != ACPI_TYPE_POWER) {
155 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
156 			 "questionable power resource object %s\n",
157 			 acpi_name(res)));
158 	status = AE_TYPE;
159 	goto out;
160     }
161     rp->ap_systemlevel = obj->PowerResource.SystemLevel;
162     rp->ap_order = obj->PowerResource.ResourceOrder;
163 
164     /* Sort the resource into the list */
165     status = AE_OK;
166     srp = TAILQ_FIRST(&acpi_powerresources);
167     if (srp == NULL || rp->ap_order < srp->ap_order) {
168 	TAILQ_INSERT_HEAD(&acpi_powerresources, rp, ap_link);
169 	goto done;
170     }
171     TAILQ_FOREACH(srp, &acpi_powerresources, ap_link) {
172 	if (rp->ap_order < srp->ap_order) {
173 	    TAILQ_INSERT_BEFORE(srp, rp, ap_link);
174 	    goto done;
175 	}
176     }
177     TAILQ_INSERT_TAIL(&acpi_powerresources, rp, ap_link);
178 
179  done:
180     ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
181 		     "registered power resource %s\n", acpi_name(res)));
182 
183  out:
184     if (buf.Pointer != NULL)
185 	AcpiOsFree(buf.Pointer);
186     if (ACPI_FAILURE(status) && rp != NULL)
187 	free(rp, M_ACPIPWR);
188     return_ACPI_STATUS (status);
189 }
190 
191 #ifdef notyet
192 /*
193  * Deregister a power resource.
194  */
195 static ACPI_STATUS
acpi_pwr_deregister_resource(ACPI_HANDLE res)196 acpi_pwr_deregister_resource(ACPI_HANDLE res)
197 {
198     struct acpi_powerresource	*rp;
199 
200     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
201     ACPI_SERIAL_ASSERT(powerres);
202 
203     rp = NULL;
204 
205     /* Find the resource */
206     if ((rp = acpi_pwr_find_resource(res)) == NULL)
207 	return_ACPI_STATUS (AE_BAD_PARAMETER);
208 
209     /* Check that there are no consumers referencing this resource */
210     if (TAILQ_FIRST(&rp->ap_references) != NULL)
211 	return_ACPI_STATUS (AE_BAD_PARAMETER);
212 
213     /* Pull it off the list and free it */
214     TAILQ_REMOVE(&acpi_powerresources, rp, ap_link);
215     free(rp, M_ACPIPWR);
216 
217     ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "deregistered power resource %s\n",
218 		     acpi_name(res)));
219 
220     return_ACPI_STATUS (AE_OK);
221 }
222 #endif /* notyet */
223 
224 /*
225  * Register a power consumer.
226  *
227  * It's OK to call this if we already know about the consumer.
228  */
229 static ACPI_STATUS
acpi_pwr_register_consumer(ACPI_HANDLE consumer)230 acpi_pwr_register_consumer(ACPI_HANDLE consumer)
231 {
232     struct acpi_powerconsumer	*pc;
233 
234     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
235     ACPI_SERIAL_ASSERT(powerres);
236 
237     /* Check to see whether we know about this consumer already */
238     if (acpi_pwr_find_consumer(consumer) != NULL)
239 	return_ACPI_STATUS (AE_OK);
240 
241     /* Allocate a new power consumer */
242     if ((pc = malloc(sizeof(*pc), M_ACPIPWR, M_NOWAIT)) == NULL)
243 	return_ACPI_STATUS (AE_NO_MEMORY);
244     TAILQ_INSERT_HEAD(&acpi_powerconsumers, pc, ac_link);
245     TAILQ_INIT(&pc->ac_references);
246     pc->ac_consumer = consumer;
247 
248     /* XXX we should try to find its current state */
249     pc->ac_state = ACPI_STATE_UNKNOWN;
250 
251     ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "registered power consumer %s\n",
252 		     acpi_name(consumer)));
253 
254     return_ACPI_STATUS (AE_OK);
255 }
256 
257 #ifdef notyet
258 /*
259  * Deregister a power consumer.
260  *
261  * This should only be done once the consumer has been powered off.
262  * (XXX is this correct?  Check once implemented)
263  */
264 static ACPI_STATUS
acpi_pwr_deregister_consumer(ACPI_HANDLE consumer)265 acpi_pwr_deregister_consumer(ACPI_HANDLE consumer)
266 {
267     struct acpi_powerconsumer	*pc;
268 
269     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
270     ACPI_SERIAL_ASSERT(powerres);
271 
272     /* Find the consumer */
273     if ((pc = acpi_pwr_find_consumer(consumer)) == NULL)
274 	return_ACPI_STATUS (AE_BAD_PARAMETER);
275 
276     /* Make sure the consumer's not referencing anything right now */
277     if (TAILQ_FIRST(&pc->ac_references) != NULL)
278 	return_ACPI_STATUS (AE_BAD_PARAMETER);
279 
280     /* Pull the consumer off the list and free it */
281     TAILQ_REMOVE(&acpi_powerconsumers, pc, ac_link);
282     free(pc, M_ACPIPWR);
283 
284     ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "deregistered power consumer %s\n",
285 		     acpi_name(consumer)));
286 
287     return_ACPI_STATUS (AE_OK);
288 }
289 #endif /* notyet */
290 
291 /*
292  * Set a power consumer to a particular power state.
293  */
294 ACPI_STATUS
acpi_pwr_switch_consumer(ACPI_HANDLE consumer,int state)295 acpi_pwr_switch_consumer(ACPI_HANDLE consumer, int state)
296 {
297     struct acpi_powerconsumer	*pc;
298     ACPI_HANDLE			method_handle, reslist_handle, pr0_handle;
299     ACPI_BUFFER			reslist_buffer;
300     ACPI_OBJECT			*reslist_object;
301     ACPI_STATUS			status;
302     char			*method_name, *reslist_name = NULL;
303 
304     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
305 
306     /* It's never ok to switch a non-existent consumer. */
307     if (consumer == NULL)
308 	return_ACPI_STATUS (AE_NOT_FOUND);
309     reslist_buffer.Pointer = NULL;
310     reslist_object = NULL;
311     ACPI_SERIAL_BEGIN(powerres);
312 
313     /* Find the consumer */
314     if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) {
315 	if (ACPI_FAILURE(status = acpi_pwr_register_consumer(consumer)))
316 	    goto out;
317 	if ((pc = acpi_pwr_find_consumer(consumer)) == NULL)
318 	    panic("acpi added power consumer but can't find it");
319     }
320 
321     /* Stop here if we're already at the target D-state. */
322     if (pc->ac_state == state) {
323 	status = AE_OK;
324 	goto out;
325     }
326 
327     /*
328      * Check for valid transitions.  From D3hot or D3cold, we can only go to D0.
329      * The exception to this is going from D3hot to D3cold or the other way
330      * around.  This is because they both use _PS3, so the only difference when
331      * doing these transitions is whether or not the power resources for _PR3
332      * are on for devices which support D3cold, and turning these power
333      * resources on/off is always perfectly fine (ACPI 7.3.11).
334      */
335     status = AE_BAD_PARAMETER;
336     if (pc->ac_state == ACPI_STATE_D3_HOT && state != ACPI_STATE_D0 &&
337 	state != ACPI_STATE_D3_COLD)
338 	goto out;
339     if (pc->ac_state == ACPI_STATE_D3_COLD && state != ACPI_STATE_D0 &&
340 	state != ACPI_STATE_D3_HOT)
341 	goto out;
342 
343     /* Find transition mechanism(s) */
344     switch (state) {
345     case ACPI_STATE_D0:
346 	method_name = "_PS0";
347 	reslist_name = "_PR0";
348 	break;
349     case ACPI_STATE_D1:
350 	method_name = "_PS1";
351 	reslist_name = "_PR1";
352 	break;
353     case ACPI_STATE_D2:
354 	method_name = "_PS2";
355 	reslist_name = "_PR2";
356 	break;
357     case ACPI_STATE_D3_HOT:
358 	method_name = "_PS3";
359 	reslist_name = "_PR3";
360 	break;
361     case ACPI_STATE_D3_COLD:
362 	method_name = "_PS3";
363 	reslist_name = NULL;
364 	break;
365     default:
366 	goto out;
367     }
368     ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "setup to switch %s %s -> %s\n",
369 		     acpi_name(consumer), acpi_d_state_to_str(pc->ac_state),
370 		     acpi_d_state_to_str(state)));
371 
372     /*
373      * Verify that this state is supported, ie. one of method or
374      * reslist must be present.  We need to do this before we go
375      * dereferencing resources (since we might be trying to go to
376      * a state we don't support).
377      *
378      * Note that if any states are supported, the device has to
379      * support D0 and D3.  It's never an error to try to go to
380      * D0.
381      */
382     if (ACPI_FAILURE(AcpiGetHandle(consumer, method_name, &method_handle)))
383 	method_handle = NULL;
384     if (reslist_name == NULL ||
385 	ACPI_FAILURE(AcpiGetHandle(consumer, reslist_name, &reslist_handle)))
386 	reslist_handle = NULL;
387     if (reslist_handle == NULL && method_handle == NULL) {
388 	if (state == ACPI_STATE_D0) {
389 	    pc->ac_state = ACPI_STATE_D0;
390 	    status = AE_OK;
391 	    goto out;
392 	}
393 	if (state == ACPI_STATE_D3_COLD)
394 	    state = ACPI_STATE_D3_HOT;
395 	if (state != ACPI_STATE_D3_HOT) {
396 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
397 		"attempt to set unsupported state %s\n",
398 		acpi_d_state_to_str(state)));
399 	    goto out;
400 	}
401 
402 	/*
403 	 * Turn off the resources listed in _PR0 to go to D3.  If there is
404 	 * no _PR0 method, this object doesn't support ACPI power states.
405 	 */
406 	if (ACPI_FAILURE(AcpiGetHandle(consumer, "_PR0", &pr0_handle))) {
407 	    status = AE_NOT_FOUND;
408 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
409 		"device missing _PR0 (desired state was %s)\n",
410 		acpi_d_state_to_str(state)));
411 	    goto out;
412 	}
413 	reslist_buffer.Length = ACPI_ALLOCATE_BUFFER;
414 	status = AcpiEvaluateObject(pr0_handle, NULL, NULL, &reslist_buffer);
415 	if (ACPI_FAILURE(status)) {
416 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
417 		"can't evaluate _PR0 for device %s, state %s\n",
418 		acpi_name(consumer), acpi_d_state_to_str(state)));
419 	    goto out;
420 	}
421 	reslist_object = (ACPI_OBJECT *)reslist_buffer.Pointer;
422 	if (!ACPI_PKG_VALID(reslist_object, 1)) {
423 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
424 		"invalid package object for state %s\n",
425 		acpi_d_state_to_str(state)));
426 	    status = AE_TYPE;
427 	    goto out;
428 	}
429 	AcpiOsFree(reslist_buffer.Pointer);
430 	reslist_buffer.Pointer = NULL;
431 	reslist_object = NULL;
432     }
433 
434     /*
435      * Check that we can actually fetch the list of power resources
436      */
437     if (reslist_handle != NULL) {
438 	reslist_buffer.Length = ACPI_ALLOCATE_BUFFER;
439 	status = AcpiEvaluateObject(reslist_handle, NULL, NULL,
440 				    &reslist_buffer);
441 	if (ACPI_FAILURE(status)) {
442 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
443 			     "can't evaluate resource list %s\n",
444 			     acpi_name(reslist_handle)));
445 	    goto out;
446 	}
447 	reslist_object = (ACPI_OBJECT *)reslist_buffer.Pointer;
448 	if (reslist_object->Type != ACPI_TYPE_PACKAGE) {
449 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
450 			     "resource list is not ACPI_TYPE_PACKAGE (%d)\n",
451 			     reslist_object->Type));
452 	    status = AE_TYPE;
453 	    goto out;
454 	}
455     }
456 
457     /*
458      * Now we are ready to switch, so kill off any current power
459      * resource references.
460      */
461     acpi_pwr_dereference_resource(pc);
462 
463     /*
464      * Add new power resource references, if we have any.  Traverse the
465      * package that we got from evaluating reslist_handle, and look up each
466      * of the resources that are referenced.
467      */
468     if (reslist_object != NULL) {
469 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "referencing %d new resources\n",
470 			  reslist_object->Package.Count));
471 	acpi_ForeachPackageObject(reslist_object, acpi_pwr_reference_resource,
472 				  pc);
473     }
474 
475     /*
476      * If we changed anything in the resource list, we need to run a switch
477      * pass now.
478      */
479     if (ACPI_FAILURE(status = acpi_pwr_switch_power())) {
480 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
481 			 "failed to switch resources from %s to %s\n",
482 			  acpi_name(consumer), acpi_d_state_to_str(state)));
483 
484 	/* XXX is this appropriate?  Should we return to previous state? */
485 	goto out;
486     }
487 
488     /* Invoke power state switch method (if present) */
489     if (method_handle != NULL) {
490 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
491 			 "invoking state transition method %s\n",
492 			 acpi_name(method_handle)));
493 	status = AcpiEvaluateObject(method_handle, NULL, NULL, NULL);
494 	if (ACPI_FAILURE(status)) {
495 		ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "failed to set state - %s\n",
496 				 AcpiFormatException(status)));
497 		pc->ac_state = ACPI_STATE_UNKNOWN;
498 
499 		/* XXX Should we return to previous state? */
500 		goto out;
501 	}
502     }
503 
504     /* Transition was successful */
505     pc->ac_state = state;
506     status = AE_OK;
507 
508 out:
509     ACPI_SERIAL_END(powerres);
510     if (reslist_buffer.Pointer != NULL)
511 	AcpiOsFree(reslist_buffer.Pointer);
512     return_ACPI_STATUS (status);
513 }
514 
515 /* Enable or disable a power resource for wake */
516 ACPI_STATUS
acpi_pwr_wake_enable(ACPI_HANDLE consumer,int enable)517 acpi_pwr_wake_enable(ACPI_HANDLE consumer, int enable)
518 {
519     ACPI_STATUS status;
520     struct acpi_powerconsumer *pc;
521     struct acpi_prw_data prw;
522     int i;
523 
524     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
525 
526     if (consumer == NULL)
527 	return (AE_BAD_PARAMETER);
528 
529     ACPI_SERIAL_BEGIN(powerres);
530     if ((pc = acpi_pwr_find_consumer(consumer)) == NULL) {
531 	if (ACPI_FAILURE(status = acpi_pwr_register_consumer(consumer)))
532 	    goto out;
533 	if ((pc = acpi_pwr_find_consumer(consumer)) == NULL)
534 	    panic("acpi wake added power consumer but can't find it");
535     }
536 
537     status = AE_OK;
538     if (acpi_parse_prw(consumer, &prw) != 0)
539 	goto out;
540     for (i = 0; i < prw.power_res_count; i++)
541 	if (enable)
542 	    acpi_pwr_reference_resource(&prw.power_res[i], pc);
543 	else
544 	    acpi_pwr_dereference_resource(pc);
545 
546     if (prw.power_res_count > 0)
547 	acpi_pwr_switch_power();
548 
549 out:
550     ACPI_SERIAL_END(powerres);
551     return (status);
552 }
553 
554 /*
555  * Called to create a reference between a power consumer and a power resource
556  * identified in the object.
557  */
558 static void
acpi_pwr_reference_resource(ACPI_OBJECT * obj,void * arg)559 acpi_pwr_reference_resource(ACPI_OBJECT *obj, void *arg)
560 {
561     struct acpi_powerconsumer	*pc = (struct acpi_powerconsumer *)arg;
562     struct acpi_powerreference	*pr;
563     struct acpi_powerresource	*rp;
564     ACPI_HANDLE			res;
565     ACPI_STATUS			status;
566 
567     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
568     ACPI_SERIAL_ASSERT(powerres);
569 
570     res = acpi_GetReference(NULL, obj);
571     if (res == NULL) {
572 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
573 			 "can't create a power reference for object type %d\n",
574 			 obj->Type));
575 	return_VOID;
576     }
577 
578     /* Create/look up the resource */
579     if (ACPI_FAILURE(status = acpi_pwr_register_resource(res))) {
580 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
581 			 "couldn't register power resource %s - %s\n",
582 			 obj->String.Pointer, AcpiFormatException(status)));
583 	return_VOID;
584     }
585     if ((rp = acpi_pwr_find_resource(res)) == NULL) {
586 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "power resource list corrupted\n"));
587 	return_VOID;
588     }
589     ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "found power resource %s\n",
590 		     acpi_name(rp->ap_resource)));
591 
592     /* Create a reference between the consumer and resource */
593     if ((pr = malloc(sizeof(*pr), M_ACPIPWR, M_NOWAIT | M_ZERO)) == NULL) {
594 	ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
595 			 "allocation failed for a power consumer reference\n"));
596 	return_VOID;
597     }
598     pr->ar_consumer = pc;
599     pr->ar_resource = rp;
600     TAILQ_INSERT_TAIL(&pc->ac_references, pr, ar_clink);
601     TAILQ_INSERT_TAIL(&rp->ap_references, pr, ar_rlink);
602 
603     return_VOID;
604 }
605 
606 static int
acpi_pwr_dereference_resource(struct acpi_powerconsumer * pc)607 acpi_pwr_dereference_resource(struct acpi_powerconsumer *pc)
608 {
609     struct acpi_powerreference *pr;
610     int changed;
611 
612     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
613     ACPI_SERIAL_ASSERT(powerres);
614 
615     changed = 0;
616     while ((pr = TAILQ_FIRST(&pc->ac_references)) != NULL) {
617         ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "removing reference to %s\n",
618                          acpi_name(pr->ar_resource->ap_resource)));
619         TAILQ_REMOVE(&pr->ar_resource->ap_references, pr, ar_rlink);
620         TAILQ_REMOVE(&pc->ac_references, pr, ar_clink);
621         free(pr, M_ACPIPWR);
622         changed = 1;
623     }
624 
625     return (changed);
626 }
627 
628 /*
629  * Switch power resources to conform to the desired state.
630  *
631  * Consumers may have modified the power resource list in an arbitrary
632  * fashion; we sweep it in sequence order.
633  */
634 static ACPI_STATUS
acpi_pwr_switch_power(void)635 acpi_pwr_switch_power(void)
636 {
637     struct acpi_powerresource	*rp;
638     ACPI_STATUS			status;
639     int				cur;
640 
641     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
642     ACPI_SERIAL_ASSERT(powerres);
643 
644     /*
645      * Sweep the list forwards turning things on.
646      */
647     TAILQ_FOREACH(rp, &acpi_powerresources, ap_link) {
648 	if (TAILQ_FIRST(&rp->ap_references) == NULL) {
649 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
650 			     "%s has no references, not turning on\n",
651 			     acpi_name(rp->ap_resource)));
652 	    continue;
653 	}
654 
655 	status = acpi_GetInteger(rp->ap_resource, "_STA", &cur);
656 	if (ACPI_FAILURE(status)) {
657 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "can't get status of %s - %d\n",
658 			      acpi_name(rp->ap_resource), status));
659 	    /* XXX is this correct?  Always switch if in doubt? */
660 	    continue;
661 	}
662 
663 	/*
664 	 * Switch if required.  Note that we ignore the result of the switch
665 	 * effort; we don't know what to do if it fails, so checking wouldn't
666 	 * help much.
667 	 */
668 	if (cur != ACPI_PWR_ON) {
669 	    status = AcpiEvaluateObject(rp->ap_resource, "_ON", NULL, NULL);
670 	    if (ACPI_FAILURE(status)) {
671 		ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
672 				 "failed to switch %s on - %s\n",
673 				 acpi_name(rp->ap_resource),
674 				 AcpiFormatException(status)));
675 	    } else {
676 		ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "switched %s on\n",
677 				 acpi_name(rp->ap_resource)));
678 	    }
679 	} else {
680 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "%s is already on\n",
681 			     acpi_name(rp->ap_resource)));
682 	}
683     }
684 
685     /* Sweep the list backwards turning things off. */
686     TAILQ_FOREACH_REVERSE(rp, &acpi_powerresources, acpi_powerresource_list,
687 	ap_link) {
688 	if (TAILQ_FIRST(&rp->ap_references) != NULL) {
689 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
690 			     "%s has references, not turning off\n",
691 			     acpi_name(rp->ap_resource)));
692 	    continue;
693 	}
694 
695 	status = acpi_GetInteger(rp->ap_resource, "_STA", &cur);
696 	if (ACPI_FAILURE(status)) {
697 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "can't get status of %s - %d\n",
698 			      acpi_name(rp->ap_resource), status));
699 	    /* XXX is this correct?  Always switch if in doubt? */
700 	    continue;
701 	}
702 
703 	/*
704 	 * Switch if required.  Note that we ignore the result of the switch
705 	 * effort; we don't know what to do if it fails, so checking wouldn't
706 	 * help much.
707 	 */
708 	if (cur != ACPI_PWR_OFF) {
709 	    status = AcpiEvaluateObject(rp->ap_resource, "_OFF", NULL, NULL);
710 	    if (ACPI_FAILURE(status)) {
711 		ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS,
712 				 "failed to switch %s off - %s\n",
713 				 acpi_name(rp->ap_resource),
714 				 AcpiFormatException(status)));
715 	    } else {
716 		ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "switched %s off\n",
717 				 acpi_name(rp->ap_resource)));
718 	    }
719 	} else {
720 	    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "%s is already off\n",
721 			     acpi_name(rp->ap_resource)));
722 	}
723     }
724 
725     return_ACPI_STATUS (AE_OK);
726 }
727 
728 /*
729  * Find a power resource's control structure.
730  */
731 static struct acpi_powerresource *
acpi_pwr_find_resource(ACPI_HANDLE res)732 acpi_pwr_find_resource(ACPI_HANDLE res)
733 {
734     struct acpi_powerresource	*rp;
735 
736     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
737     ACPI_SERIAL_ASSERT(powerres);
738 
739     TAILQ_FOREACH(rp, &acpi_powerresources, ap_link) {
740 	if (rp->ap_resource == res)
741 	    break;
742     }
743 
744     return_PTR (rp);
745 }
746 
747 /*
748  * Find a power consumer's control structure.
749  */
750 static struct acpi_powerconsumer *
acpi_pwr_find_consumer(ACPI_HANDLE consumer)751 acpi_pwr_find_consumer(ACPI_HANDLE consumer)
752 {
753     struct acpi_powerconsumer	*pc;
754 
755     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
756     ACPI_SERIAL_ASSERT(powerres);
757 
758     TAILQ_FOREACH(pc, &acpi_powerconsumers, ac_link) {
759 	if (pc->ac_consumer == consumer)
760 	    break;
761     }
762 
763     return_PTR (pc);
764 }
765