xref: /freebsd/sys/dev/acpi_support/acpi_wmi.c (revision 724b4bfdf1306e4f2c451b6d146fe0fe0353b2c8)
1 /*-
2  * Copyright (c) 2009 Michael Gmelin <freebsd@grem.de>
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 __FBSDID("$FreeBSD$");
29 
30 /*
31  * Driver for acpi-wmi mapping, provides an interface for vendor specific
32  * implementations (e.g. HP and Acer laptops).
33  * Inspired by the ACPI-WMI mapping driver (c) 2008-2008 Carlos Corbacho which
34  * implements this functionality for Linux.
35  *
36  * WMI and ACPI: http://www.microsoft.com/whdc/system/pnppwr/wmi/wmi-acpi.mspx
37  * acpi-wmi for Linux: http://www.kernel.org
38  */
39 
40 #include "opt_acpi.h"
41 #include <sys/param.h>
42 #include <sys/conf.h>
43 #include <sys/uio.h>
44 #include <sys/proc.h>
45 #include <sys/kernel.h>
46 #include <sys/malloc.h>
47 #include <sys/sbuf.h>
48 #include <sys/module.h>
49 #include <sys/bus.h>
50 
51 #include <contrib/dev/acpica/include/acpi.h>
52 #include <contrib/dev/acpica/include/accommon.h>
53 #include <dev/acpica/acpivar.h>
54 #include "acpi_wmi_if.h"
55 
56 static MALLOC_DEFINE(M_ACPIWMI, "acpiwmi", "ACPI-WMI mapping");
57 
58 #define _COMPONENT	ACPI_OEM
59 ACPI_MODULE_NAME("ACPI_WMI");
60 
61 #define ACPI_WMI_REGFLAG_EXPENSIVE	0x1 /* GUID flag: Expensive operation */
62 #define ACPI_WMI_REGFLAG_METHOD		0x2	/* GUID flag: Method call */
63 #define ACPI_WMI_REGFLAG_STRING		0x4	/* GUID flag: String */
64 #define ACPI_WMI_REGFLAG_EVENT		0x8	/* GUID flag: Event */
65 
66 /*
67  * acpi_wmi driver private structure
68  */
69 struct acpi_wmi_softc {
70 	device_t	wmi_dev;	/* wmi device id */
71 	ACPI_HANDLE	wmi_handle;	/* handle of the PNP0C14 node */
72 	device_t	ec_dev;		/* acpi_ec0 */
73 	struct cdev	*wmistat_dev_t;	/* wmistat device handle */
74 	struct sbuf	wmistat_sbuf;	/* sbuf for /dev/wmistat output */
75 	pid_t		wmistat_open_pid; /* pid operating on /dev/wmistat */
76 	int		wmistat_bufptr;	/* /dev/wmistat ptr to buffer position */
77 	TAILQ_HEAD(wmi_info_list_head, wmi_info) wmi_info_list;
78 };
79 
80 /*
81  * Struct that holds information about
82  * about a single GUID entry in _WDG
83  */
84 struct guid_info {
85 	char	guid[16];	/* 16 byte non human readable GUID */
86 	char	oid[2];		/* object id or event notify id (first byte) */
87 	UINT8	max_instance;	/* highest instance known for this GUID */
88 	UINT8	flags;		/* ACPI_WMI_REGFLAG_%s */
89 };
90 
91 /* WExx event generation state (on/off) */
92 enum event_generation_state {
93 	EVENT_GENERATION_ON = 1,
94 	EVENT_GENERATION_OFF = 0
95 };
96 
97 
98 /*
99  * Information about one entry in _WDG.
100  * List of those is used to lookup information by GUID.
101  */
102 struct wmi_info {
103 	TAILQ_ENTRY(wmi_info)	wmi_list;
104 	struct guid_info	ginfo;		/* information on guid */
105 	ACPI_NOTIFY_HANDLER	event_handler;/* client provided event handler */
106 	void			*event_handler_user_data; /* ev handler cookie  */
107 };
108 
109 
110 ACPI_SERIAL_DECL(acpi_wmi, "ACPI-WMI Mapping");
111 
112 /* public interface - declaration */
113 /* standard device interface*/
114 static int		acpi_wmi_probe(device_t dev);
115 static int		acpi_wmi_attach(device_t dev);
116 static int		acpi_wmi_detach(device_t dev);
117 /* see acpi_wmi_if.m */
118 static int		acpi_wmi_provides_guid_string_method(device_t dev,
119 			    const char *guid_string);
120 static ACPI_STATUS	acpi_wmi_evaluate_call_method(device_t dev,
121 			    const char *guid_string, UINT8 instance,
122 			    UINT32 method_id, const ACPI_BUFFER *in,
123 			    ACPI_BUFFER *out);
124 static ACPI_STATUS	acpi_wmi_install_event_handler_method(device_t dev,
125 			    const char *guid_string, ACPI_NOTIFY_HANDLER handler,
126 			    void *data);
127 static ACPI_STATUS	acpi_wmi_remove_event_handler_method(device_t dev,
128 			    const char *guid_string);
129 static ACPI_STATUS	acpi_wmi_get_event_data_method(device_t dev,
130 			    UINT32 event_id, ACPI_BUFFER *out);
131 static ACPI_STATUS	acpi_wmi_get_block_method(device_t dev,
132 			    const char *guid_string,
133 			    UINT8 instance, ACPI_BUFFER *out);
134 static ACPI_STATUS	acpi_wmi_set_block_method(device_t dev,
135 			    const char *guid_string,
136 			    UINT8 instance, const ACPI_BUFFER *in);
137 /* private interface - declaration */
138 /* callbacks */
139 static void		acpi_wmi_notify_handler(ACPI_HANDLE h, UINT32 notify,
140 			    void *context);
141 static ACPI_STATUS	acpi_wmi_ec_handler(UINT32 function,
142 			    ACPI_PHYSICAL_ADDRESS address, UINT32 width,
143 			    UINT64 *value, void *context,
144 			    void *region_context);
145 /* helpers */
146 static ACPI_STATUS	acpi_wmi_read_wdg_blocks(struct acpi_wmi_softc *sc, ACPI_HANDLE h);
147 static ACPI_STATUS	acpi_wmi_toggle_we_event_generation(device_t dev,
148 			    struct wmi_info *winfo,
149 			    enum event_generation_state state);
150 static int		acpi_wmi_guid_string_to_guid(const UINT8 *guid_string,
151 			    UINT8 *guid);
152 static struct wmi_info* acpi_wmi_lookup_wmi_info_by_guid_string(struct acpi_wmi_softc *sc,
153 			    const char *guid_string);
154 
155 static d_open_t acpi_wmi_wmistat_open;
156 static d_close_t acpi_wmi_wmistat_close;
157 static d_read_t acpi_wmi_wmistat_read;
158 
159 /* handler /dev/wmistat device */
160 static struct cdevsw wmistat_cdevsw = {
161 	.d_version = D_VERSION,
162 	.d_open = acpi_wmi_wmistat_open,
163 	.d_close = acpi_wmi_wmistat_close,
164 	.d_read = acpi_wmi_wmistat_read,
165 	.d_name = "wmistat",
166 };
167 
168 
169 static device_method_t acpi_wmi_methods[] = {
170 	/* Device interface */
171 	DEVMETHOD(device_probe,	acpi_wmi_probe),
172 	DEVMETHOD(device_attach, acpi_wmi_attach),
173 	DEVMETHOD(device_detach, acpi_wmi_detach),
174 
175 	/* bus interface */
176 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
177 
178 	/* acpi_wmi interface */
179 	DEVMETHOD(acpi_wmi_provides_guid_string,
180 		    acpi_wmi_provides_guid_string_method),
181 	DEVMETHOD(acpi_wmi_evaluate_call, acpi_wmi_evaluate_call_method),
182 	DEVMETHOD(acpi_wmi_install_event_handler,
183 		    acpi_wmi_install_event_handler_method),
184 	DEVMETHOD(acpi_wmi_remove_event_handler,
185 		    acpi_wmi_remove_event_handler_method),
186 	DEVMETHOD(acpi_wmi_get_event_data, acpi_wmi_get_event_data_method),
187 	DEVMETHOD(acpi_wmi_get_block, acpi_wmi_get_block_method),
188 	DEVMETHOD(acpi_wmi_set_block, acpi_wmi_set_block_method),
189 
190 	DEVMETHOD_END
191 };
192 
193 static driver_t acpi_wmi_driver = {
194 	"acpi_wmi",
195 	acpi_wmi_methods,
196 	sizeof(struct acpi_wmi_softc),
197 };
198 
199 static devclass_t acpi_wmi_devclass;
200 DRIVER_MODULE(acpi_wmi, acpi, acpi_wmi_driver, acpi_wmi_devclass, 0, 0);
201 MODULE_VERSION(acpi_wmi, 1);
202 MODULE_DEPEND(acpi_wmi, acpi, 1, 1, 1);
203 static char *wmi_ids[] = {"PNP0C14", NULL};
204 
205 /*
206  * Probe for the PNP0C14 ACPI node
207  */
208 static int
209 acpi_wmi_probe(device_t dev)
210 {
211 	if (acpi_disabled("wmi") ||
212 	    ACPI_ID_PROBE(device_get_parent(dev), dev, wmi_ids) == NULL)
213 		return (ENXIO);
214 	device_set_desc(dev, "ACPI-WMI mapping");
215 
216 	return (0);
217 }
218 
219 /*
220  * Attach the device by:
221  * - Looking for the first ACPI EC device
222  * - Install the notify handler
223  * - Install the EC address space handler
224  * - Look for the _WDG node and read GUID information blocks
225  */
226 static int
227 acpi_wmi_attach(device_t dev)
228 {
229 	struct acpi_wmi_softc *sc;
230 	int ret;
231 	ACPI_STATUS status;
232 
233 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
234 	sc = device_get_softc(dev);
235 	ret = ENXIO;
236 
237 	ACPI_SERIAL_BEGIN(acpi_wmi);
238 	sc->wmi_dev = dev;
239 	sc->wmi_handle = acpi_get_handle(dev);
240 	TAILQ_INIT(&sc->wmi_info_list);
241 	/* XXX Only works with one EC, but nearly all systems only have one. */
242 	if ((sc->ec_dev = devclass_get_device(devclass_find("acpi_ec"), 0))
243 	    == NULL)
244 		device_printf(dev, "cannot find EC device\n");
245 	else if (ACPI_FAILURE((status = AcpiInstallNotifyHandler(sc->wmi_handle,
246 		    ACPI_DEVICE_NOTIFY, acpi_wmi_notify_handler, sc))))
247 		device_printf(sc->wmi_dev, "couldn't install notify handler - %s\n",
248 		    AcpiFormatException(status));
249 	else if (ACPI_FAILURE((status = AcpiInstallAddressSpaceHandler(
250 		    sc->wmi_handle, ACPI_ADR_SPACE_EC, acpi_wmi_ec_handler,
251 		    NULL, sc)))) {
252 		device_printf(sc->wmi_dev, "couldn't install EC handler - %s\n",
253 		    AcpiFormatException(status));
254 		AcpiRemoveNotifyHandler(sc->wmi_handle, ACPI_DEVICE_NOTIFY,
255 		    acpi_wmi_notify_handler);
256 	} else if (ACPI_FAILURE((status = acpi_wmi_read_wdg_blocks(sc,
257 		    sc->wmi_handle)))) {
258 		device_printf(sc->wmi_dev, "couldn't parse _WDG - %s\n",
259 		    AcpiFormatException(status));
260 		AcpiRemoveNotifyHandler(sc->wmi_handle, ACPI_DEVICE_NOTIFY,
261 		    acpi_wmi_notify_handler);
262 		AcpiRemoveAddressSpaceHandler(sc->wmi_handle, ACPI_ADR_SPACE_EC,
263 		    acpi_wmi_ec_handler);
264 	} else {
265 		sc->wmistat_dev_t = make_dev(&wmistat_cdevsw, 0, UID_ROOT,
266 		    GID_WHEEL, 0644, "wmistat%d", device_get_unit(dev));
267 		sc->wmistat_dev_t->si_drv1 = sc;
268 		sc->wmistat_open_pid = 0;
269 		sc->wmistat_bufptr = -1;
270 		ret = 0;
271 	}
272 	ACPI_SERIAL_END(acpi_wmi);
273 
274 	if (ret == 0) {
275 		bus_generic_probe(dev);
276 		ret = bus_generic_attach(dev);
277 	}
278 
279 	return (ret);
280 }
281 
282 /*
283  * Detach the driver by:
284  * - Removing notification handler
285  * - Removing address space handler
286  * - Turning off event generation for all WExx event activated by
287  *   child drivers
288  */
289 static int
290 acpi_wmi_detach(device_t dev)
291 {
292 	struct wmi_info *winfo, *tmp;
293 	struct acpi_wmi_softc *sc;
294 	int ret;
295 
296 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
297 	sc = device_get_softc(dev);
298 	ACPI_SERIAL_BEGIN(acpi_wmi);
299 
300 	if (sc->wmistat_open_pid != 0) {
301 		ret = EBUSY;
302 	} else {
303 		AcpiRemoveNotifyHandler(sc->wmi_handle, ACPI_DEVICE_NOTIFY,
304 		    acpi_wmi_notify_handler);
305 		AcpiRemoveAddressSpaceHandler(sc->wmi_handle,
306 		    ACPI_ADR_SPACE_EC, acpi_wmi_ec_handler);
307 		TAILQ_FOREACH_SAFE(winfo, &sc->wmi_info_list, wmi_list, tmp) {
308 			if (winfo->event_handler)
309 				acpi_wmi_toggle_we_event_generation(dev,
310 				    winfo, EVENT_GENERATION_OFF);
311 			TAILQ_REMOVE(&sc->wmi_info_list, winfo, wmi_list);
312 			free(winfo, M_ACPIWMI);
313 		}
314 		if (sc->wmistat_bufptr != -1) {
315 			sbuf_delete(&sc->wmistat_sbuf);
316 			sc->wmistat_bufptr = -1;
317 		}
318 		sc->wmistat_open_pid = 0;
319 		destroy_dev(sc->wmistat_dev_t);
320 		ret = 0;
321 	}
322 	ACPI_SERIAL_END(acpi_wmi);
323 
324 	return (ret);
325 }
326 
327 
328 /*
329  * Check if the given GUID string (human readable format
330  * AABBCCDD-EEFF-GGHH-IIJJ-KKLLMMNNOOPP)
331  * exists within _WDG
332  */
333 static int
334 acpi_wmi_provides_guid_string_method(device_t dev, const char *guid_string)
335 {
336 	struct acpi_wmi_softc *sc;
337 	struct wmi_info *winfo;
338 	int ret;
339 
340 	sc = device_get_softc(dev);
341 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
342 	ACPI_SERIAL_BEGIN(acpi_wmi);
343 	winfo = acpi_wmi_lookup_wmi_info_by_guid_string(sc, guid_string);
344 	ret = (winfo == NULL)?0:winfo->ginfo.max_instance+1;
345 	ACPI_SERIAL_END(acpi_wmi);
346 
347 	return (ret);
348 }
349 
350 /*
351  * Call a method "method_id" on the given GUID block
352  * write result into user provided output buffer
353  */
354 static ACPI_STATUS
355 acpi_wmi_evaluate_call_method(device_t dev, const char *guid_string,
356     UINT8 instance, UINT32 method_id, const ACPI_BUFFER *in, ACPI_BUFFER *out)
357 {
358 	ACPI_OBJECT params[3];
359 	ACPI_OBJECT_LIST input;
360 	char method[5] = "WMxx";
361 	struct wmi_info *winfo;
362 	struct acpi_wmi_softc *sc;
363 	ACPI_STATUS status;
364 
365 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
366 
367 	sc = device_get_softc(dev);
368 	ACPI_SERIAL_BEGIN(acpi_wmi);
369 	if ((winfo = acpi_wmi_lookup_wmi_info_by_guid_string(sc, guid_string))
370 		    == NULL)
371 		status = AE_NOT_FOUND;
372 	else if (!(winfo->ginfo.flags & ACPI_WMI_REGFLAG_METHOD))
373 		status = AE_BAD_DATA;
374 	else if (instance > winfo->ginfo.max_instance)
375 		status = AE_BAD_PARAMETER;
376 	else {
377 		params[0].Type = ACPI_TYPE_INTEGER;
378 		params[0].Integer.Value = instance;
379 		params[1].Type = ACPI_TYPE_INTEGER;
380 		params[1].Integer.Value = method_id;
381 		input.Pointer = params;
382 		input.Count = 2;
383 		if (in) {
384 			params[2].Type =
385 			    (winfo->ginfo.flags & ACPI_WMI_REGFLAG_STRING)
386 			    ?ACPI_TYPE_STRING:ACPI_TYPE_BUFFER;
387 			params[2].Buffer.Length = in->Length;
388 			params[2].Buffer.Pointer = in->Pointer;
389 			input.Count = 3;
390 		}
391 		method[2] = winfo->ginfo.oid[0];
392 		method[3] = winfo->ginfo.oid[1];
393 		status = AcpiEvaluateObject(sc->wmi_handle, method,
394 			    &input, out);
395 	}
396 	ACPI_SERIAL_END(acpi_wmi);
397 
398 	return (status);
399 }
400 
401 /*
402  * Install a user provided event_handler on the given GUID
403  * provided *data will be passed on callback
404  * If there is already an existing event handler registered it will be silently
405  * discarded
406  */
407 static ACPI_STATUS
408 acpi_wmi_install_event_handler_method(device_t dev, const char *guid_string,
409     ACPI_NOTIFY_HANDLER event_handler, void *data)
410 {
411 	struct acpi_wmi_softc *sc = device_get_softc(dev);
412 	struct wmi_info *winfo;
413 	ACPI_STATUS status;
414 
415 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
416 
417 	status = AE_OK;
418 	ACPI_SERIAL_BEGIN(acpi_wmi);
419 	if (guid_string == NULL || event_handler == NULL)
420 		status = AE_BAD_PARAMETER;
421 	else if ((winfo = acpi_wmi_lookup_wmi_info_by_guid_string(sc, guid_string))
422 		    == NULL)
423 		status = AE_NOT_EXIST;
424 	else if (winfo->event_handler != NULL ||
425 		(status = acpi_wmi_toggle_we_event_generation(dev, winfo,
426 		    EVENT_GENERATION_ON)) == AE_OK) {
427 		winfo->event_handler = event_handler;
428 		winfo->event_handler_user_data = data;
429 	}
430 	ACPI_SERIAL_END(acpi_wmi);
431 
432 	return (status);
433 }
434 
435 /*
436  * Remove a previously installed event handler from the given GUID
437  * If there was none installed, this call is silently discarded and
438  * reported as AE_OK
439  */
440 static ACPI_STATUS
441 acpi_wmi_remove_event_handler_method(device_t dev, const char *guid_string)
442 {
443 	struct acpi_wmi_softc *sc = device_get_softc(dev);
444 	struct wmi_info *winfo;
445 	ACPI_STATUS status;
446 
447 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
448 
449 	status = AE_OK;
450 	ACPI_SERIAL_BEGIN(acpi_wmi);
451 	if (guid_string &&
452 	    (winfo = acpi_wmi_lookup_wmi_info_by_guid_string(sc, guid_string))
453 	    != NULL && winfo->event_handler) {
454 		status = acpi_wmi_toggle_we_event_generation(dev, winfo,
455 			    EVENT_GENERATION_OFF);
456 		winfo->event_handler = NULL;
457 		winfo->event_handler_user_data = NULL;
458 	}
459 	ACPI_SERIAL_END(acpi_wmi);
460 
461 	return (status);
462 }
463 
464 /*
465  * Get details on an event received through a callback registered
466  * through ACPI_WMI_REMOVE_EVENT_HANDLER into a user provided output buffer.
467  * (event_id equals "notify" passed in the callback)
468  */
469 static ACPI_STATUS
470 acpi_wmi_get_event_data_method(device_t dev, UINT32 event_id, ACPI_BUFFER *out)
471 {
472 	ACPI_OBJECT_LIST input;
473 	ACPI_OBJECT params[1];
474 	struct acpi_wmi_softc *sc;
475 	struct wmi_info *winfo;
476 	ACPI_STATUS status;
477 
478 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
479 
480 	sc = device_get_softc(dev);
481 	status = AE_NOT_FOUND;
482 	ACPI_SERIAL_BEGIN(acpi_wmi);
483 	params[0].Type = ACPI_TYPE_INTEGER;
484 	params[0].Integer.Value = event_id;
485 	input.Pointer = params;
486 	input.Count = 1;
487 	TAILQ_FOREACH(winfo, &sc->wmi_info_list, wmi_list) {
488 		if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) &&
489 		    ((UINT8) winfo->ginfo.oid[0] == event_id)) {
490 			status = AcpiEvaluateObject(sc->wmi_handle, "_WED",
491 				    &input, out);
492 			break;
493 		}
494 	}
495 	ACPI_SERIAL_END(acpi_wmi);
496 
497 	return (status);
498 }
499 
500 /*
501  * Read a block of data from the given GUID (using WQxx (query))
502  * Will be returned in a user provided buffer (out).
503  * If the method is marked as expensive (ACPI_WMI_REGFLAG_EXPENSIVE)
504  * we will first call the WCxx control method to lock the node to
505  * lock the node for data collection and release it afterwards.
506  * (Failed WCxx calls are ignored to "support" broken implementations)
507  */
508 static ACPI_STATUS
509 acpi_wmi_get_block_method(device_t dev, const char *guid_string, UINT8 instance,
510 	ACPI_BUFFER *out)
511 {
512 	char wc_method[5] = "WCxx";
513 	char wq_method[5] = "WQxx";
514 	ACPI_OBJECT_LIST wc_input;
515 	ACPI_OBJECT_LIST wq_input;
516 	ACPI_OBJECT wc_params[1];
517 	ACPI_OBJECT wq_params[1];
518 	ACPI_HANDLE wc_handle;
519 	struct acpi_wmi_softc *sc;
520 	struct wmi_info *winfo;
521 	ACPI_STATUS status;
522 	ACPI_STATUS wc_status;
523 
524 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
525 
526 	sc = device_get_softc(dev);
527 	wc_status = AE_ERROR;
528 	ACPI_SERIAL_BEGIN(acpi_wmi);
529 	if (guid_string == NULL || out == NULL)
530 		status = AE_BAD_PARAMETER;
531 	else if ((winfo = acpi_wmi_lookup_wmi_info_by_guid_string(sc, guid_string))
532 		    == NULL)
533 		status = AE_ERROR;
534 	else if (instance > winfo->ginfo.max_instance)
535 		status = AE_BAD_PARAMETER;
536 	else if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) ||
537 	    (winfo->ginfo.flags & ACPI_WMI_REGFLAG_METHOD))
538 		status = AE_ERROR;
539 	else {
540 		wq_params[0].Type = ACPI_TYPE_INTEGER;
541 		wq_params[0].Integer.Value = instance;
542 		wq_input.Pointer = wq_params;
543 		wq_input.Count = 1;
544 		if (winfo->ginfo.flags & ACPI_WMI_REGFLAG_EXPENSIVE) {
545 			wc_params[0].Type = ACPI_TYPE_INTEGER;
546 			wc_params[0].Integer.Value = 1;
547 			wc_input.Pointer = wc_params;
548 			wc_input.Count = 1;
549 			wc_method[2] = winfo->ginfo.oid[0];
550 			wc_method[3] = winfo->ginfo.oid[1];
551 			wc_status = AcpiGetHandle(sc->wmi_handle, wc_method,
552 				    &wc_handle);
553 			if (ACPI_SUCCESS(wc_status))
554 				wc_status = AcpiEvaluateObject(wc_handle,
555 						wc_method, &wc_input, NULL);
556 		}
557 		wq_method[2] = winfo->ginfo.oid[0];
558 		wq_method[3] = winfo->ginfo.oid[1];
559 		status = AcpiEvaluateObject(sc->wmi_handle, wq_method,
560 			    &wq_input, out);
561 		if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EXPENSIVE)
562 		    && ACPI_SUCCESS(wc_status)) {
563 			wc_params[0].Integer.Value = 0;
564 			status = AcpiEvaluateObject(wc_handle, wc_method,
565 				    &wc_input, NULL);  /* XXX this might be
566 				    			 the wrong status to
567 				    			 return? */
568 		}
569 	}
570 	ACPI_SERIAL_END(acpi_wmi);
571 
572 	return (status);
573 }
574 
575 /*
576  * Write a block of data to the given GUID (using WSxx)
577  */
578 static ACPI_STATUS
579 acpi_wmi_set_block_method(device_t dev, const char *guid_string, UINT8 instance,
580 	const ACPI_BUFFER *in)
581 {
582 	char method[5] = "WSxx";
583 	ACPI_OBJECT_LIST input;
584 	ACPI_OBJECT params[2];
585 	struct wmi_info *winfo;
586 	struct acpi_wmi_softc *sc;
587 	ACPI_STATUS status;
588 
589 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
590 
591 	sc = device_get_softc(dev);
592 	ACPI_SERIAL_BEGIN(acpi_wmi);
593 	if (guid_string == NULL || in == NULL)
594 		status = AE_BAD_DATA;
595 	else if ((winfo = acpi_wmi_lookup_wmi_info_by_guid_string(sc, guid_string))
596 		    == NULL)
597 		status = AE_ERROR;
598 	else if (instance > winfo->ginfo.max_instance)
599 		status = AE_BAD_PARAMETER;
600 	else if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) ||
601 		    (winfo->ginfo.flags & ACPI_WMI_REGFLAG_METHOD))
602 		status = AE_ERROR;
603 	else {
604 		params[0].Type = ACPI_TYPE_INTEGER;
605 		params[0].Integer.Value = instance;
606 		input.Pointer = params;
607 		input.Count = 2;
608 		params[1].Type = (winfo->ginfo.flags & ACPI_WMI_REGFLAG_STRING)
609 		    ?ACPI_TYPE_STRING:ACPI_TYPE_BUFFER;
610 		params[1].Buffer.Length = in->Length;
611 		params[1].Buffer.Pointer = in->Pointer;
612 		method[2] = winfo->ginfo.oid[0];
613 		method[3] = winfo->ginfo.oid[1];
614 		status = AcpiEvaluateObject(sc->wmi_handle, method,
615 			    &input, NULL);
616 	}
617 	ACPI_SERIAL_END(acpi_wmi);
618 
619 	return (status);
620 }
621 
622 /*
623  * Handle events received and dispatch them to
624  * stakeholders that registered through ACPI_WMI_INSTALL_EVENT_HANDLER
625  */
626 static void
627 acpi_wmi_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
628 {
629 	struct acpi_wmi_softc *sc = context;
630 	ACPI_NOTIFY_HANDLER handler;
631 	void *handler_data;
632 	struct wmi_info *winfo;
633 
634 	ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, notify);
635 
636 	handler = NULL;
637 	handler_data = NULL;
638 	ACPI_SERIAL_BEGIN(acpi_wmi);
639 	TAILQ_FOREACH(winfo, &sc->wmi_info_list, wmi_list) {
640 		if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) &&
641 				((UINT8) winfo->ginfo.oid[0] == notify)) {
642 			if (winfo->event_handler) {
643 				handler = winfo->event_handler;
644 				handler_data = winfo->event_handler_user_data;
645 				break;
646 			}
647 		}
648 	}
649 	ACPI_SERIAL_END(acpi_wmi);
650 	if (handler) {
651 		handler(h, notify, handler_data);
652 	}
653 }
654 
655 /*
656  * Handle EC address space notifications reveived on the WDG node
657  * (this mimics EcAddressSpaceHandler in acpi_ec.c)
658  */
659 static ACPI_STATUS
660 acpi_wmi_ec_handler(UINT32 function, ACPI_PHYSICAL_ADDRESS address,
661     UINT32 width, UINT64 *value, void *context,
662     void *region_context)
663 {
664 	struct acpi_wmi_softc *sc;
665 	int i;
666 	UINT64 ec_data;
667 	UINT8 ec_addr;
668 	ACPI_STATUS status;
669 
670 	ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, (UINT32)address);
671 
672 	sc = (struct acpi_wmi_softc *)context;
673 	if (width % 8 != 0 || value == NULL || context == NULL)
674 		return (AE_BAD_PARAMETER);
675 	if (address + (width / 8) - 1 > 0xFF)
676 		return (AE_BAD_ADDRESS);
677 	if (function == ACPI_READ)
678 		*value = 0;
679 	ec_addr = address;
680 	status = AE_ERROR;
681 
682 	for (i = 0; i < width; i += 8, ++ec_addr) {
683 		switch (function) {
684 		case ACPI_READ:
685 			status = ACPI_EC_READ(sc->ec_dev, ec_addr, &ec_data, 1);
686 			if (ACPI_SUCCESS(status))
687 				*value |= ((UINT64)ec_data) << i;
688 		break;
689 		case ACPI_WRITE:
690 			ec_data = (UINT8)((*value) >> i);
691 			status = ACPI_EC_WRITE(sc->ec_dev, ec_addr, ec_data, 1);
692 			break;
693 		default:
694 			device_printf(sc->wmi_dev,
695 			    "invalid acpi_wmi_ec_handler function %d\n",
696 			    function);
697 			status = AE_BAD_PARAMETER;
698 			break;
699 		}
700 		if (ACPI_FAILURE(status))
701 			break;
702 	}
703 
704 	return (status);
705 }
706 
707 /*
708  * Read GUID blocks from the _WDG node
709  * into wmi_info_list.
710  */
711 static ACPI_STATUS
712 acpi_wmi_read_wdg_blocks(struct acpi_wmi_softc *sc, ACPI_HANDLE h)
713 {
714 	ACPI_BUFFER out = {ACPI_ALLOCATE_BUFFER, NULL};
715 	struct guid_info *ginfo;
716 	ACPI_OBJECT *obj;
717 	struct wmi_info *winfo;
718 	UINT32 i;
719 	UINT32 wdg_block_count;
720 	ACPI_STATUS status;
721 
722 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
723 
724 	ACPI_SERIAL_ASSERT(acpi_wmi);
725 	if (ACPI_FAILURE(status = AcpiEvaluateObject(h, "_WDG", NULL, &out)))
726 		return (status);
727 	obj = (ACPI_OBJECT*) out.Pointer;
728 	wdg_block_count = obj->Buffer.Length / sizeof(struct guid_info);
729 	if ((ginfo = malloc(obj->Buffer.Length, M_ACPIWMI, M_NOWAIT))
730 		    == NULL) {
731 		AcpiOsFree(out.Pointer);
732 		return (AE_NO_MEMORY);
733 	}
734 	memcpy(ginfo, obj->Buffer.Pointer, obj->Buffer.Length);
735 	for (i = 0; i < wdg_block_count; ++i) {
736 		if ((winfo = malloc(sizeof(struct wmi_info), M_ACPIWMI,
737 			    M_NOWAIT | M_ZERO)) == NULL) {
738 			AcpiOsFree(out.Pointer);
739 			free(ginfo, M_ACPIWMI);
740 			return (AE_NO_MEMORY);
741 		}
742 		winfo->ginfo = ginfo[i];
743 		TAILQ_INSERT_TAIL(&sc->wmi_info_list, winfo, wmi_list);
744 	}
745 	AcpiOsFree(out.Pointer);
746 	free(ginfo, M_ACPIWMI);
747 
748 	return (status);
749 }
750 
751 /*
752  * Toggle event generation in for the given GUID (passed by winfo)
753  * Turn on to get notified (through acpi_wmi_notify_handler) if events happen
754  * on the given GUID.
755  */
756 static ACPI_STATUS
757 acpi_wmi_toggle_we_event_generation(device_t dev, struct wmi_info *winfo,
758     enum event_generation_state state)
759 {
760 	char method[5] = "WExx";
761 	ACPI_OBJECT_LIST input;
762 	ACPI_OBJECT params[1];
763 	struct acpi_wmi_softc *sc;
764 	ACPI_STATUS status;
765 
766 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
767 
768 	sc = device_get_softc(dev);
769 	ACPI_SERIAL_ASSERT(acpi_wmi);
770 	params[0].Type = ACPI_TYPE_INTEGER;
771 	params[0].Integer.Value = state==EVENT_GENERATION_ON?1:0;
772 	input.Pointer = params;
773 	input.Count = 1;
774 
775 	UINT8 hi = ((UINT8) winfo->ginfo.oid[0]) >> 4;
776 	UINT8 lo = ((UINT8) winfo->ginfo.oid[0]) & 0xf;
777 	method[2] = (hi > 9 ? hi + 55: hi + 48);
778 	method[3] = (lo > 9 ? lo + 55: lo + 48);
779 	status = AcpiEvaluateObject(sc->wmi_handle, method, &input, NULL);
780 	if (status == AE_NOT_FOUND) status = AE_OK;
781 
782 	return (status);
783 }
784 
785 /*
786  * Convert given two digit hex string (hexin) to an UINT8 referenced
787  * by byteout.
788  * Return != 0 if the was a problem (invalid input)
789  */
790 static __inline int acpi_wmi_hex_to_int(const UINT8 *hexin, UINT8 *byteout)
791 {
792 	unsigned int hi;
793 	unsigned int lo;
794 
795 	hi = hexin[0];
796 	lo = hexin[1];
797 	if ('0' <= hi && hi <= '9')
798 		hi -= '0';
799 	else if ('A' <= hi && hi <= 'F')
800 		hi -= ('A' - 10);
801 	else if ('a' <= hi && hi <= 'f')
802 		hi -= ('a' - 10);
803 	else
804 		return (1);
805 	if ('0' <= lo && lo <= '9')
806 		lo -= '0';
807 	else if ('A' <= lo && lo <= 'F')
808 		lo -= ('A' - 10);
809 	else if ('a' <= lo && lo <= 'f')
810 		lo -= ('a' - 10);
811 	else
812 		return (1);
813 	*byteout = (hi << 4) + lo;
814 
815 	return (0);
816 }
817 
818 /*
819  * Convert a human readable 36 character GUID into a 16byte
820  * machine readable one.
821  * The basic algorithm looks as follows:
822  * Input:  AABBCCDD-EEFF-GGHH-IIJJ-KKLLMMNNOOPP
823  * Output: DCBAFEHGIJKLMNOP
824  * (AA BB CC etc. represent two digit hex numbers == bytes)
825  * Return != 0 if passed guid string is invalid
826  */
827 static int
828 acpi_wmi_guid_string_to_guid(const UINT8 *guid_string, UINT8 *guid)
829 {
830 	static const int mapping[20] = {3, 2, 1, 0, -1, 5, 4, -1, 7, 6, -1,
831 	    8, 9, -1, 10, 11, 12, 13, 14, 15};
832 	int i;
833 
834 	for (i = 0; i < 20; ++i, ++guid_string) {
835 		if (mapping[i] >= 0) {
836 			if (acpi_wmi_hex_to_int(guid_string,
837 			    &guid[mapping[i]]))
838 				return (-1);
839 			++guid_string;
840 		} else if (*guid_string != '-')
841 			return (-1);
842 	}
843 
844 	return (0);
845 }
846 
847 /*
848  * Lookup a wmi_info structure in wmi_list based on a
849  * human readable GUID
850  * Return NULL if the GUID is unknown in the _WDG
851  */
852 static struct wmi_info*
853 acpi_wmi_lookup_wmi_info_by_guid_string(struct acpi_wmi_softc *sc, const char *guid_string)
854 {
855 	char guid[16];
856 	struct wmi_info *winfo;
857 
858 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
859 
860 	ACPI_SERIAL_ASSERT(acpi_wmi);
861 
862 	if (!acpi_wmi_guid_string_to_guid(guid_string, guid)) {
863 		TAILQ_FOREACH(winfo, &sc->wmi_info_list, wmi_list) {
864 			if (!memcmp(winfo->ginfo.guid, guid, 16)) {
865 				return (winfo);
866 			}
867 		}
868 	}
869 
870 	return (NULL);
871 }
872 
873 /*
874  * open wmistat device
875  */
876 static int
877 acpi_wmi_wmistat_open(struct cdev* dev, int flags, int mode, struct thread *td)
878 {
879 	struct acpi_wmi_softc *sc;
880 	int ret;
881 
882 	if (dev == NULL || dev->si_drv1 == NULL)
883 		return (EBADF);
884 	sc = dev->si_drv1;
885 
886 	ACPI_SERIAL_BEGIN(acpi_wmi);
887 	if (sc->wmistat_open_pid != 0) {
888 		ret = EBUSY;
889 	}
890 	else {
891 		if (sbuf_new(&sc->wmistat_sbuf, NULL, 4096, SBUF_AUTOEXTEND)
892 			    == NULL) {
893 			ret = ENXIO;
894 		} else {
895 			sc->wmistat_open_pid = td->td_proc->p_pid;
896 			sc->wmistat_bufptr = 0;
897 			ret = 0;
898 		}
899 	}
900 	ACPI_SERIAL_END(acpi_wmi);
901 
902 	return (ret);
903 }
904 
905 /*
906  * close wmistat device
907  */
908 static int
909 acpi_wmi_wmistat_close(struct cdev* dev, int flags, int mode,
910     struct thread *td)
911 {
912 	struct acpi_wmi_softc *sc;
913 	int ret;
914 
915 	if (dev == NULL || dev->si_drv1 == NULL)
916 		return (EBADF);
917 	sc = dev->si_drv1;
918 
919 	ACPI_SERIAL_BEGIN(acpi_wmi);
920 	if (sc->wmistat_open_pid == 0) {
921 		ret = EBADF;
922 	}
923 	else {
924 		if (sc->wmistat_bufptr != -1) {
925 			sbuf_delete(&sc->wmistat_sbuf);
926 			sc->wmistat_bufptr = -1;
927 		}
928 		sc->wmistat_open_pid = 0;
929 		ret = 0;
930 	}
931 	ACPI_SERIAL_END(acpi_wmi);
932 
933 	return (ret);
934 }
935 
936 /*
937  * Read from wmistat guid information
938  */
939 static int
940 acpi_wmi_wmistat_read(struct cdev *dev, struct uio *buf, int flag)
941 {
942 	struct acpi_wmi_softc *sc;
943 	struct wmi_info *winfo;
944 	int l;
945 	int ret;
946 	UINT8* guid;
947 
948 	if (dev == NULL || dev->si_drv1 == NULL)
949 		return (EBADF);
950 	sc = dev->si_drv1;
951 
952 	ACPI_SERIAL_BEGIN(acpi_wmi);
953 	if (sc->wmistat_open_pid != buf->uio_td->td_proc->p_pid ||
954 			sc->wmistat_bufptr == -1) {
955 		ret = EBADF;
956 	}
957 	else {
958 		if (!sbuf_done(&sc->wmistat_sbuf)) {
959 			sbuf_printf(&sc->wmistat_sbuf, "GUID                 "
960 				    "                 INST EXPE METH STR "
961 				    "EVENT OID\n");
962 			TAILQ_FOREACH(winfo, &sc->wmi_info_list, wmi_list) {
963 				guid = (UINT8*)winfo->ginfo.guid;
964 				sbuf_printf(&sc->wmistat_sbuf,
965 					    "{%02X%02X%02X%02X-%02X%02X-"
966 					    "%02X%02X-%02X%02X-%02X%02X"
967 					    "%02X%02X%02X%02X} %3d %-5s",
968 					guid[3], guid[2], guid[1], guid[0],
969 					guid[5], guid[4],
970 					guid[7], guid[6],
971 					guid[8], guid[9],
972 					guid[10], guid[11], guid[12],
973 					guid[13], guid[14], guid[15],
974 					winfo->ginfo.max_instance,
975 					(winfo->ginfo.flags&
976 						ACPI_WMI_REGFLAG_EXPENSIVE)?
977 						"YES":"NO"
978 					);
979 				if (winfo->ginfo.flags&ACPI_WMI_REGFLAG_METHOD)
980 					sbuf_printf(&sc->wmistat_sbuf,
981 						    "WM%c%c ",
982 						    winfo->ginfo.oid[0],
983 						    winfo->ginfo.oid[1]);
984 				else
985 					sbuf_printf(&sc->wmistat_sbuf, "NO   ");
986 				sbuf_printf(&sc->wmistat_sbuf, "%-4s",
987 					    (winfo->ginfo.flags&
988 					    ACPI_WMI_REGFLAG_STRING)?"YES":"NO"
989 					);
990 				if (winfo->ginfo.flags&ACPI_WMI_REGFLAG_EVENT)
991 					sbuf_printf(&sc->wmistat_sbuf,
992 						    "0x%02X%s -\n",
993 						    (UINT8)winfo->ginfo.oid[0],
994 						    winfo->event_handler==NULL?
995 						    " ":"+");
996 				else
997 					sbuf_printf(&sc->wmistat_sbuf,
998 						    "NO    %c%c\n",
999 						    winfo->ginfo.oid[0],
1000 						    winfo->ginfo.oid[1]);
1001 			}
1002 			sbuf_finish(&sc->wmistat_sbuf);
1003 		}
1004 		if (sbuf_len(&sc->wmistat_sbuf) <= 0) {
1005 			sbuf_delete(&sc->wmistat_sbuf);
1006 			sc->wmistat_bufptr = -1;
1007 			sc->wmistat_open_pid = 0;
1008 			ret = ENOMEM;
1009 		} else {
1010 			l = min(buf->uio_resid, sbuf_len(&sc->wmistat_sbuf) -
1011 				    sc->wmistat_bufptr);
1012 			ret = (l > 0)?uiomove(sbuf_data(&sc->wmistat_sbuf) +
1013 				    sc->wmistat_bufptr, l, buf) : 0;
1014 			sc->wmistat_bufptr += l;
1015 		}
1016 	}
1017 	ACPI_SERIAL_END(acpi_wmi);
1018 
1019 	return (ret);
1020 }
1021