xref: /netbsd-src/sys/dev/acpi/wmi/wmi_acpi.c (revision bbde328be4e75ea9ad02e9715ea13ca54b797ada)
1 /*	$NetBSD: wmi_acpi.c,v 1.4 2010/04/15 07:02:24 jruoho Exp $	*/
2 
3 /*-
4  * Copyright (c) 2009, 2010 Jukka Ruohonen <jruohonen@iki.fi>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: wmi_acpi.c,v 1.4 2010/04/15 07:02:24 jruoho Exp $");
31 
32 #include <sys/param.h>
33 #include <sys/device.h>
34 #include <sys/endian.h>
35 #include <sys/kmem.h>
36 #include <sys/systm.h>
37 
38 #include <dev/acpi/acpireg.h>
39 #include <dev/acpi/acpivar.h>
40 #include <dev/acpi/wmi/wmi_acpivar.h>
41 
42 #define _COMPONENT          ACPI_RESOURCE_COMPONENT
43 ACPI_MODULE_NAME            ("wmi_acpi")
44 
45 /*
46  * This implements something called "Microsoft Windows Management
47  * Instrumentation" (WMI). This subset of ACPI is desribed in:
48  *
49  * http://www.microsoft.com/whdc/system/pnppwr/wmi/wmi-acpi.mspx
50  *
51  * (Obtained on Thu Feb 12 18:21:44 EET 2009.)
52  */
53 struct guid_t {
54 
55 	/*
56 	 * The GUID itself. The used format is the usual 32-16-16-64-bit
57 	 * representation. All except the fourth field are in native byte
58 	 * order. A 32-16-16-16-48-bit hexadecimal notation with hyphens
59 	 * is used for human-readable GUIDs.
60 	 */
61 	struct {
62 		uint32_t data1;
63 		uint16_t data2;
64 		uint16_t data3;
65 		uint8_t  data4[8];
66 	} __packed;
67 
68 	union {
69 		char oid[2];            /* ACPI object ID. */
70 
71 		struct {
72 			uint8_t nid;    /* Notification value. */
73 			uint8_t res;    /* Reserved. */
74 		} __packed;
75 	} __packed;
76 
77 	uint8_t count;	                /* Number of instances. */
78 	uint8_t flags;		        /* Additional flags. */
79 
80 } __packed;
81 
82 struct wmi_t {
83 	struct guid_t         guid;
84 	bool                  eevent;
85 
86 	SIMPLEQ_ENTRY(wmi_t)  wmi_link;
87 };
88 
89 struct acpi_wmi_softc {
90 	device_t	      sc_dev;
91 	device_t              sc_child;
92         ACPI_NOTIFY_HANDLER   sc_handler;
93 	struct acpi_devnode  *sc_node;
94 
95 	SIMPLEQ_HEAD(, wmi_t) wmi_head;
96 };
97 
98 #define ACPI_WMI_FLAG_EXPENSIVE 0x01
99 #define ACPI_WMI_FLAG_METHOD    0x02
100 #define ACPI_WMI_FLAG_STRING    0x04
101 #define ACPI_WMI_FLAG_EVENT     0x08
102 #define ACPI_WMI_FLAG_DATA      (ACPI_WMI_FLAG_EXPENSIVE |		\
103 	                         ACPI_WMI_FLAG_STRING)
104 
105 #define UGET16(x)   (*(uint16_t *)(x))
106 #define UGET64(x)   (*(uint64_t *)(x))
107 
108 #define HEXCHAR(x)  (((x) >= '0' && (x) <= '9') ||			\
109 	             ((x) >= 'a' && (x) <= 'f') ||			\
110 		     ((x) >= 'A' && (x) <= 'F'))
111 
112 #define GUIDCMP(a, b)							\
113 	((a)->data1 == (b)->data1 &&					\
114 	 (a)->data2 == (b)->data2 &&					\
115 	 (a)->data3 == (b)->data3 &&					\
116 	 UGET64((a)->data4) == UGET64((b)->data4))
117 
118 static int         acpi_wmi_match(device_t, cfdata_t, void *);
119 static void        acpi_wmi_attach(device_t, device_t, void *);
120 static int         acpi_wmi_detach(device_t, int);
121 static int         acpi_wmi_print(void *, const char *);
122 static bool        acpi_wmi_init(struct acpi_wmi_softc *);
123 static bool        acpi_wmi_add(struct acpi_wmi_softc *, ACPI_OBJECT *);
124 static void        acpi_wmi_del(struct acpi_wmi_softc *);
125 
126 #ifdef ACPIVERBOSE
127 static void        acpi_wmi_dump(struct acpi_wmi_softc *);
128 #endif
129 
130 static ACPI_STATUS acpi_wmi_guid_get(struct acpi_wmi_softc *,
131                                      const char *, struct wmi_t **);
132 static void	   acpi_wmi_event_add(struct acpi_wmi_softc *);
133 static void	   acpi_wmi_event_del(struct acpi_wmi_softc *);
134 static void        acpi_wmi_event_handler(ACPI_HANDLE, uint32_t, void *);
135 static bool        acpi_wmi_suspend(device_t, const pmf_qual_t *);
136 static bool        acpi_wmi_resume(device_t, const pmf_qual_t *);
137 static ACPI_STATUS acpi_wmi_enable(ACPI_HANDLE, const char *, bool, bool);
138 static bool        acpi_wmi_input(struct wmi_t *, uint8_t, uint8_t);
139 
140 const char * const acpi_wmi_ids[] = {
141 	"PNP0C14",
142 	NULL
143 };
144 
145 CFATTACH_DECL_NEW(acpiwmi, sizeof(struct acpi_wmi_softc),
146     acpi_wmi_match, acpi_wmi_attach, acpi_wmi_detach, NULL);
147 
148 static int
149 acpi_wmi_match(device_t parent, cfdata_t match, void *aux)
150 {
151 	struct acpi_attach_args *aa = aux;
152 
153 	if (aa->aa_node->ad_type != ACPI_TYPE_DEVICE)
154 		return 0;
155 
156 	return acpi_match_hid(aa->aa_node->ad_devinfo, acpi_wmi_ids);
157 }
158 
159 static void
160 acpi_wmi_attach(device_t parent, device_t self, void *aux)
161 {
162 	struct acpi_wmi_softc *sc = device_private(self);
163 	struct acpi_attach_args *aa = aux;
164 
165 	sc->sc_dev = self;
166 	sc->sc_node = aa->aa_node;
167 
168 	sc->sc_child = NULL;
169 	sc->sc_handler = NULL;
170 
171 	aprint_naive("\n");
172 	aprint_normal(": ACPI WMI Interface\n");
173 
174 	if (acpi_wmi_init(sc) != true)
175 		return;
176 
177 #ifdef ACPIVERBOSE
178 	acpi_wmi_dump(sc);
179 #endif
180 
181 	acpi_wmi_event_add(sc);
182 
183 	sc->sc_child = config_found_ia(self, "acpiwmibus",
184 	    NULL, acpi_wmi_print);
185 
186 	(void)pmf_device_register(self, acpi_wmi_suspend, acpi_wmi_resume);
187 }
188 
189 static int
190 acpi_wmi_detach(device_t self, int flags)
191 {
192 	struct acpi_wmi_softc *sc = device_private(self);
193 
194 	acpi_wmi_event_del(sc);
195 
196 	if (sc->sc_child != NULL)
197 		(void)config_detach(sc->sc_child, flags);
198 
199 	acpi_wmi_del(sc);
200 	pmf_device_deregister(self);
201 
202 	return 0;
203 }
204 
205 static int
206 acpi_wmi_print(void *aux, const char *pnp)
207 {
208 
209 	if (pnp != NULL)
210 		aprint_normal("acpiwmibus at %s", pnp);
211 
212 	return UNCONF;
213 }
214 
215 static bool
216 acpi_wmi_init(struct acpi_wmi_softc *sc)
217 {
218 	ACPI_OBJECT *obj;
219 	ACPI_BUFFER buf;
220 	ACPI_STATUS rv;
221 	uint32_t len;
222 
223 	rv = acpi_eval_struct(sc->sc_node->ad_handle, "_WDG", &buf);
224 
225 	if (ACPI_FAILURE(rv))
226 		goto fail;
227 
228 	obj = buf.Pointer;
229 
230 	if (obj->Type != ACPI_TYPE_BUFFER) {
231 		rv = AE_TYPE;
232 		goto fail;
233 	}
234 
235 	len = obj->Buffer.Length;
236 
237 	if (len != obj->Package.Count) {
238 		rv = AE_BAD_VALUE;
239 		goto fail;
240 	}
241 
242 	CTASSERT(sizeof(struct guid_t) == 20);
243 
244 	if (len < sizeof(struct guid_t) ||
245 	    len % sizeof(struct guid_t) != 0) {
246 		rv = AE_BAD_DATA;
247 		goto fail;
248 	}
249 
250 	return acpi_wmi_add(sc, obj);
251 
252 fail:
253 	aprint_error_dev(sc->sc_dev, "failed to evaluate _WDG: %s\n",
254 	    AcpiFormatException(rv));
255 
256 	if (buf.Pointer != NULL)
257 		ACPI_FREE(buf.Pointer);
258 
259 	return false;
260 }
261 
262 static bool
263 acpi_wmi_add(struct acpi_wmi_softc *sc, ACPI_OBJECT *obj)
264 {
265 	struct wmi_t *wmi;
266 	size_t i, n, offset, siz;
267 
268 	siz = sizeof(struct guid_t);
269 	n = obj->Buffer.Length / siz;
270 
271 	SIMPLEQ_INIT(&sc->wmi_head);
272 
273 	for (i = offset = 0; i < n; ++i) {
274 
275 		if ((wmi = kmem_zalloc(sizeof(*wmi), KM_NOSLEEP)) == NULL)
276 			goto fail;
277 
278 		(void)memcpy(&wmi->guid, obj->Buffer.Pointer + offset, siz);
279 
280 		wmi->eevent = false;
281 		offset = offset + siz;
282 
283 		SIMPLEQ_INSERT_TAIL(&sc->wmi_head, wmi, wmi_link);
284 	}
285 
286 	ACPI_FREE(obj);
287 
288 	return true;
289 
290 fail:
291 	ACPI_FREE(obj);
292 	acpi_wmi_del(sc);
293 
294 	return false;
295 }
296 
297 static void
298 acpi_wmi_del(struct acpi_wmi_softc *sc)
299 {
300 	struct wmi_t *wmi;
301 
302 	if (SIMPLEQ_EMPTY(&sc->wmi_head) != 0)
303 		return;
304 
305 	while (SIMPLEQ_FIRST(&sc->wmi_head) != NULL) {
306 
307 		wmi = SIMPLEQ_FIRST(&sc->wmi_head);
308 		SIMPLEQ_REMOVE_HEAD(&sc->wmi_head, wmi_link);
309 
310 		KASSERT(wmi != NULL);
311 
312 		kmem_free(wmi, sizeof(*wmi));
313 	}
314 }
315 
316 #ifdef ACPIVERBOSE
317 static void
318 acpi_wmi_dump(struct acpi_wmi_softc *sc)
319 {
320 	struct wmi_t *wmi;
321 
322 	KASSERT(SIMPLEQ_EMPTY(&sc->wmi_head) == 0);
323 
324 	SIMPLEQ_FOREACH(wmi, &sc->wmi_head, wmi_link) {
325 
326 		aprint_normal_dev(sc->sc_dev, "{%08X-%04X-%04X-",
327 		    wmi->guid.data1, wmi->guid.data2, wmi->guid.data3);
328 
329 		aprint_normal("%02X%02X-%02X%02X%02X%02X%02X%02X} ",
330 		    wmi->guid.data4[0], wmi->guid.data4[1],
331 		    wmi->guid.data4[2], wmi->guid.data4[3],
332 		    wmi->guid.data4[4], wmi->guid.data4[5],
333 		    wmi->guid.data4[6], wmi->guid.data4[7]);
334 
335 		aprint_normal("oid %04X count %02X flags %02X\n",
336 		    UGET16(wmi->guid.oid), wmi->guid.count, wmi->guid.flags);
337 	}
338 }
339 #endif
340 
341 static ACPI_STATUS
342 acpi_wmi_guid_get(struct acpi_wmi_softc *sc,
343     const char *src, struct wmi_t **out)
344 {
345 	struct wmi_t *wmi;
346 	struct guid_t *guid;
347 	char bin[16];
348 	char hex[2];
349 	const char *ptr;
350 	uint8_t i;
351 
352 	if (sc == NULL || src == NULL || strlen(src) != 36)
353 		return AE_BAD_PARAMETER;
354 
355 	for (ptr = src, i = 0; i < 16; i++) {
356 
357 		if (*ptr == '-')
358 			ptr++;
359 
360 		(void)memcpy(hex, ptr, 2);
361 
362 		if (HEXCHAR(hex[0]) == 0 || HEXCHAR(hex[1]) == 0)
363 			return AE_BAD_HEX_CONSTANT;
364 
365 		bin[i] = strtoul(hex, NULL, 16) & 0xFF;
366 
367 		ptr++;
368 		ptr++;
369 	}
370 
371 	guid = (struct guid_t *)bin;
372 	guid->data1 = be32toh(guid->data1);
373 	guid->data2 = be16toh(guid->data2);
374 	guid->data3 = be16toh(guid->data3);
375 
376 	SIMPLEQ_FOREACH(wmi, &sc->wmi_head, wmi_link) {
377 
378 		if (GUIDCMP(guid, &wmi->guid) != 0) {
379 
380 			if (out != NULL)
381 				*out = wmi;
382 
383 			return AE_OK;
384 		}
385 	}
386 
387 	return AE_NOT_FOUND;
388 }
389 
390 /*
391  * Checks if a GUID is present. Child devices
392  * can use this in their autoconf(9) routines.
393  */
394 int
395 acpi_wmi_guid_match(device_t self, const char *guid)
396 {
397 	struct acpi_wmi_softc *sc = device_private(self);
398 	ACPI_STATUS rv;
399 
400 	rv = acpi_wmi_guid_get(sc, guid, NULL);
401 
402 	if (ACPI_SUCCESS(rv))
403 		return 1;
404 
405 	return 0;
406 }
407 
408 /*
409  * Adds internal event handler.
410  */
411 static void
412 acpi_wmi_event_add(struct acpi_wmi_softc *sc)
413 {
414 	struct wmi_t *wmi;
415 	ACPI_STATUS rv;
416 
417 	if (acpi_register_notify(sc->sc_node, acpi_wmi_event_handler) != true)
418 		return;
419 
420 	/* Enable possible expensive events. */
421 	SIMPLEQ_FOREACH(wmi, &sc->wmi_head, wmi_link) {
422 
423 		if ((wmi->guid.flags & ACPI_WMI_FLAG_EVENT) != 0 &&
424 		    (wmi->guid.flags & ACPI_WMI_FLAG_EXPENSIVE) != 0) {
425 
426 			rv = acpi_wmi_enable(sc->sc_node->ad_handle,
427 			    wmi->guid.oid, false, true);
428 
429 			if (ACPI_SUCCESS(rv)) {
430 				wmi->eevent = true;
431 				continue;
432 			}
433 
434 			aprint_error_dev(sc->sc_dev, "failed to enable "
435 			    "expensive WExx: %s\n", AcpiFormatException(rv));
436 		}
437 	}
438 }
439 
440 /*
441  * Removes the internal event handler.
442  */
443 static void
444 acpi_wmi_event_del(struct acpi_wmi_softc *sc)
445 {
446 	struct wmi_t *wmi;
447 	ACPI_STATUS rv;
448 
449 	acpi_deregister_notify(sc->sc_node);
450 
451 	SIMPLEQ_FOREACH(wmi, &sc->wmi_head, wmi_link) {
452 
453 		if (wmi->eevent != true)
454 			continue;
455 
456 		KASSERT((wmi->guid.flags & ACPI_WMI_FLAG_EVENT) != 0);
457 		KASSERT((wmi->guid.flags & ACPI_WMI_FLAG_EXPENSIVE) != 0);
458 
459 		rv = acpi_wmi_enable(sc->sc_node->ad_handle,
460 		    wmi->guid.oid, false, false);
461 
462 		if (ACPI_SUCCESS(rv)) {
463 			wmi->eevent = false;
464 			continue;
465 		}
466 
467 		aprint_error_dev(sc->sc_dev, "failed to disable "
468 		    "expensive WExx: %s\n", AcpiFormatException(rv));
469 	}
470 }
471 
472 /*
473  * Returns extra information possibly associated with an event.
474  */
475 ACPI_STATUS
476 acpi_wmi_event_get(device_t self, uint32_t event, ACPI_BUFFER *obuf)
477 {
478 	struct acpi_wmi_softc *sc = device_private(self);
479 	struct wmi_t *wmi;
480 	ACPI_OBJECT_LIST arg;
481 	ACPI_OBJECT obj;
482 	ACPI_HANDLE hdl;
483 
484 	if (sc == NULL || obuf == NULL)
485 		return AE_BAD_PARAMETER;
486 
487 	if (sc->sc_handler == NULL)
488 		return AE_ABORT_METHOD;
489 
490 	hdl = sc->sc_node->ad_handle;
491 
492 	obj.Type = ACPI_TYPE_INTEGER;
493 	obj.Integer.Value = event;
494 
495 	arg.Count = 0x01;
496 	arg.Pointer = &obj;
497 
498 	obuf->Pointer = NULL;
499 	obuf->Length = ACPI_ALLOCATE_LOCAL_BUFFER;
500 
501 	SIMPLEQ_FOREACH(wmi, &sc->wmi_head, wmi_link) {
502 
503 		if ((wmi->guid.flags & ACPI_WMI_FLAG_EVENT) == 0)
504 			continue;
505 
506 		if (wmi->guid.nid != event)
507 			continue;
508 
509 		return AcpiEvaluateObject(hdl, "_WED", &arg, obuf);
510 	}
511 
512 	return AE_NOT_FOUND;
513 }
514 
515 /*
516  * Forwards events to the external handler through the internal one.
517  */
518 static void
519 acpi_wmi_event_handler(ACPI_HANDLE hdl, uint32_t evt, void *aux)
520 {
521 	struct acpi_wmi_softc *sc;
522 	device_t self = aux;
523 
524 	sc = device_private(self);
525 
526 	if (sc->sc_child == NULL)
527 		return;
528 
529 	if (sc->sc_handler == NULL)
530 		return;
531 
532 	(*sc->sc_handler)(NULL, evt, sc->sc_child);
533 }
534 
535 ACPI_STATUS
536 acpi_wmi_event_register(device_t self, ACPI_NOTIFY_HANDLER handler)
537 {
538 	struct acpi_wmi_softc *sc = device_private(self);
539 
540 	if (sc == NULL)
541 		return AE_BAD_PARAMETER;
542 
543 	if (handler != NULL && sc->sc_handler != NULL)
544 		return AE_ALREADY_EXISTS;
545 
546 	sc->sc_handler = handler;
547 
548 	return AE_OK;
549 }
550 
551 ACPI_STATUS
552 acpi_wmi_event_deregister(device_t self)
553 {
554 	return acpi_wmi_event_register(self, NULL);
555 }
556 
557 /*
558  * As there is no prior knowledge about the expensive
559  * events that cause "significant overhead", try to
560  * disable (enable) these before suspending (resuming).
561  */
562 static bool
563 acpi_wmi_suspend(device_t self, const pmf_qual_t *qual)
564 {
565 	struct acpi_wmi_softc *sc = device_private(self);
566 
567 	acpi_wmi_event_del(sc);
568 
569 	return true;
570 }
571 
572 static bool
573 acpi_wmi_resume(device_t self, const pmf_qual_t *qual)
574 {
575 	struct acpi_wmi_softc *sc = device_private(self);
576 
577 	acpi_wmi_event_add(sc);
578 
579 	return true;
580 }
581 
582 /*
583  * Enables or disables data collection (WCxx) or an event (WExx).
584  */
585 static ACPI_STATUS
586 acpi_wmi_enable(ACPI_HANDLE hdl, const char *oid, bool data, bool flag)
587 {
588 	char path[5];
589 	const char *str;
590 
591 	str = (data != false) ? "WC" : "WE";
592 
593 	(void)strlcpy(path, str, sizeof(path));
594 	(void)strlcat(path, oid, sizeof(path));
595 
596 	return acpi_eval_set_integer(hdl, path, (flag != false) ? 0x01 : 0x00);
597 }
598 
599 static bool
600 acpi_wmi_input(struct wmi_t *wmi, uint8_t flag, uint8_t idx)
601 {
602 
603 	if ((wmi->guid.flags & flag) == 0)
604 		return false;
605 
606 	if (wmi->guid.count == 0x00)
607 		return false;
608 
609 	if (wmi->guid.count < idx)
610 		return false;
611 
612 	return true;
613 }
614 
615 /*
616  * Makes a WMI data block query (WQxx). The corresponding control
617  * method for data collection will be invoked if it is available.
618  */
619 ACPI_STATUS
620 acpi_wmi_data_query(device_t self, const char *guid,
621     uint8_t idx, ACPI_BUFFER *obuf)
622 {
623 	struct acpi_wmi_softc *sc = device_private(self);
624 	struct wmi_t *wmi;
625 	char path[5] = "WQ";
626 	ACPI_OBJECT_LIST arg;
627 	ACPI_STATUS rv, rvxx;
628 	ACPI_OBJECT obj;
629 
630 	rvxx = AE_SUPPORT;
631 
632 	if (obuf == NULL)
633 		return AE_BAD_PARAMETER;
634 
635 	rv = acpi_wmi_guid_get(sc, guid, &wmi);
636 
637 	if (ACPI_FAILURE(rv))
638 		return rv;
639 
640 	if (acpi_wmi_input(wmi, ACPI_WMI_FLAG_DATA, idx) != true)
641 		return AE_BAD_DATA;
642 
643 	(void)strlcat(path, wmi->guid.oid, sizeof(path));
644 
645 	obj.Type = ACPI_TYPE_INTEGER;
646 	obj.Integer.Value = idx;
647 
648 	arg.Count = 0x01;
649 	arg.Pointer = &obj;
650 
651 	obuf->Pointer = NULL;
652 	obuf->Length = ACPI_ALLOCATE_LOCAL_BUFFER;
653 
654 	/*
655 	 * If the expensive flag is set, we should enable
656 	 * data collection before evaluating the WQxx buffer.
657 	 */
658 	if ((wmi->guid.flags & ACPI_WMI_FLAG_EXPENSIVE) != 0) {
659 
660 		rvxx = acpi_wmi_enable(sc->sc_node->ad_handle,
661 		    wmi->guid.oid, true, true);
662 	}
663 
664 	rv = AcpiEvaluateObject(sc->sc_node->ad_handle, path, &arg, obuf);
665 
666 	/* No longer needed. */
667 	if (ACPI_SUCCESS(rvxx)) {
668 
669 		(void)acpi_wmi_enable(sc->sc_node->ad_handle,
670 		    wmi->guid.oid, true, false);
671 	}
672 
673 #ifdef DIAGNOSTIC
674 	/*
675 	 * XXX: It appears that quite a few laptops have WQxx
676 	 * methods that are declared as expensive, but lack the
677 	 * corresponding WCxx control method.
678 	 *
679 	 * -- Acer Aspire One is one example <jruohonen@iki.fi>.
680 	 */
681 	if (ACPI_FAILURE(rvxx) && rvxx != AE_SUPPORT)
682 		aprint_error_dev(sc->sc_dev, "failed to evaluate WCxx "
683 		    "for %s: %s\n", path, AcpiFormatException(rvxx));
684 #endif
685 	return rv;
686 }
687 
688 /*
689  * Writes to a data block (WSxx).
690  */
691 ACPI_STATUS
692 acpi_wmi_data_write(device_t self, const char *guid,
693     uint8_t idx, ACPI_BUFFER *ibuf)
694 {
695 	struct acpi_wmi_softc *sc = device_private(self);
696 	struct wmi_t *wmi;
697 	ACPI_OBJECT_LIST arg;
698 	ACPI_OBJECT obj[2];
699 	char path[5] = "WS";
700 	ACPI_STATUS rv;
701 
702 	if (ibuf == NULL)
703 		return AE_BAD_PARAMETER;
704 
705 	rv = acpi_wmi_guid_get(sc, guid, &wmi);
706 
707 	if (ACPI_FAILURE(rv))
708 		return rv;
709 
710 	if (acpi_wmi_input(wmi, ACPI_WMI_FLAG_DATA, idx) != true)
711 		return AE_BAD_DATA;
712 
713 	(void)strlcat(path, wmi->guid.oid, sizeof(path));
714 
715 	obj[0].Integer.Value = idx;
716 	obj[0].Type = ACPI_TYPE_INTEGER;
717 
718 	obj[1].Buffer.Length = ibuf->Length;
719 	obj[1].Buffer.Pointer = ibuf->Pointer;
720 
721 	obj[1].Type = ((wmi->guid.flags & ACPI_WMI_FLAG_STRING) != 0) ?
722 	    ACPI_TYPE_STRING : ACPI_TYPE_BUFFER;
723 
724 	arg.Count = 0x02;
725 	arg.Pointer = obj;
726 
727 	return AcpiEvaluateObject(sc->sc_node->ad_handle, path, &arg, NULL);
728 }
729 
730 /*
731  * Executes a method (WMxx).
732  */
733 ACPI_STATUS
734 acpi_wmi_method(device_t self, const char *guid, uint8_t idx,
735     uint32_t mid, ACPI_BUFFER *ibuf, ACPI_BUFFER *obuf)
736 {
737 	struct acpi_wmi_softc *sc = device_private(self);
738 	struct wmi_t *wmi;
739 	ACPI_OBJECT_LIST arg;
740 	ACPI_OBJECT obj[3];
741 	char path[5] = "WM";
742 	ACPI_STATUS rv;
743 
744 	if (ibuf == NULL || obuf == NULL)
745 		return AE_BAD_PARAMETER;
746 
747 	rv = acpi_wmi_guid_get(sc, guid, &wmi);
748 
749 	if (ACPI_FAILURE(rv))
750 		return rv;
751 
752 	if (acpi_wmi_input(wmi, ACPI_WMI_FLAG_METHOD, idx) != true)
753 		return AE_BAD_DATA;
754 
755 	(void)strlcat(path, wmi->guid.oid, sizeof(path));
756 
757 	obj[0].Integer.Value = idx;
758 	obj[1].Integer.Value = mid;
759 	obj[0].Type = obj[1].Type = ACPI_TYPE_INTEGER;
760 
761 	obj[2].Buffer.Length = ibuf->Length;
762 	obj[2].Buffer.Pointer = ibuf->Pointer;
763 
764 	obj[2].Type = ((wmi->guid.flags & ACPI_WMI_FLAG_STRING) != 0) ?
765 	    ACPI_TYPE_STRING : ACPI_TYPE_BUFFER;
766 
767 	arg.Count = 0x03;
768 	arg.Pointer = obj;
769 
770 	obuf->Pointer = NULL;
771 	obuf->Length = ACPI_ALLOCATE_LOCAL_BUFFER;
772 
773 	return AcpiEvaluateObject(sc->sc_node->ad_handle, path, &arg, obuf);
774 }
775