xref: /freebsd/sys/dev/acpi_support/acpi_wmi.c (revision 6f3544cd7084abbadd83637993a4f41fd30e6ccd)
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 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 };
78 
79 /*
80  * Struct that holds information about
81  * about a single GUID entry in _WDG
82  */
83 struct guid_info {
84 	char	guid[16];	/* 16 byte non human readable GUID */
85 	char	oid[2];		/* object id or event notify id (first byte) */
86 	UINT8	max_instance;	/* highest instance known for this GUID */
87 	UINT8	flags;		/* ACPI_WMI_REGFLAG_%s */
88 };
89 
90 /* WExx event generation state (on/off) */
91 enum event_generation_state {
92 	EVENT_GENERATION_ON = 1,
93 	EVENT_GENERATION_OFF = 0
94 };
95 
96 
97 /*
98  * Information about one entry in _WDG.
99  * List of those is used to lookup information by GUID.
100  */
101 struct wmi_info {
102 	TAILQ_ENTRY(wmi_info)	wmi_list;
103 	struct guid_info	ginfo;		/* information on guid */
104 	ACPI_NOTIFY_HANDLER	event_handler;/* client provided event handler */
105 	void			*event_handler_user_data; /* ev handler cookie  */
106 };
107 
108 TAILQ_HEAD(wmi_info_list_head, wmi_info)
109     wmi_info_list = TAILQ_HEAD_INITIALIZER(wmi_info_list);
110 
111 ACPI_SERIAL_DECL(acpi_wmi, "ACPI-WMI Mapping");
112 
113 /* public interface - declaration */
114 /* standard device interface*/
115 static int		acpi_wmi_probe(device_t dev);
116 static int		acpi_wmi_attach(device_t dev);
117 static int		acpi_wmi_detach(device_t dev);
118 /* see acpi_wmi_if.m */
119 static int		acpi_wmi_provides_guid_string_method(device_t dev,
120 			    const char *guid_string);
121 static ACPI_STATUS	acpi_wmi_evaluate_call_method(device_t dev,
122 			    const char *guid_string, UINT8 instance,
123 			    UINT32 method_id, const ACPI_BUFFER *in,
124 			    ACPI_BUFFER *out);
125 static ACPI_STATUS	acpi_wmi_install_event_handler_method(device_t dev,
126 			    const char *guid_string, ACPI_NOTIFY_HANDLER handler,
127 			    void *data);
128 static ACPI_STATUS	acpi_wmi_remove_event_handler_method(device_t dev,
129 			    const char *guid_string);
130 static ACPI_STATUS	acpi_wmi_get_event_data_method(device_t dev,
131 			    UINT32 event_id, ACPI_BUFFER *out);
132 static ACPI_STATUS	acpi_wmi_get_block_method(device_t dev,
133 			    const char *guid_string,
134 			    UINT8 instance, ACPI_BUFFER *out);
135 static ACPI_STATUS	acpi_wmi_set_block_method(device_t dev,
136 			    const char *guid_string,
137 			    UINT8 instance, const ACPI_BUFFER *in);
138 /* private interface - declaration */
139 /* callbacks */
140 static void		acpi_wmi_notify_handler(ACPI_HANDLE h, UINT32 notify,
141 			    void *context);
142 static ACPI_STATUS	acpi_wmi_ec_handler(UINT32 function,
143 			    ACPI_PHYSICAL_ADDRESS address, UINT32 width,
144 			    UINT64 *value, void *context,
145 			    void *region_context);
146 /* helpers */
147 static ACPI_STATUS	acpi_wmi_read_wdg_blocks(ACPI_HANDLE h);
148 static ACPI_STATUS	acpi_wmi_toggle_we_event_generation(device_t dev,
149 			    struct wmi_info *winfo,
150 			    enum event_generation_state state);
151 static int		acpi_wmi_guid_string_to_guid(const UINT8 *guid_string,
152 			    UINT8 *guid);
153 static struct wmi_info* acpi_wmi_lookup_wmi_info_by_guid_string(
154 			    const char *guid_string);
155 
156 static d_open_t acpi_wmi_wmistat_open;
157 static d_close_t acpi_wmi_wmistat_close;
158 static d_read_t acpi_wmi_wmistat_read;
159 
160 /* handler /dev/wmistat device */
161 static struct cdevsw wmistat_cdevsw = {
162 	.d_version = D_VERSION,
163 	.d_open = acpi_wmi_wmistat_open,
164 	.d_close = acpi_wmi_wmistat_close,
165 	.d_read = acpi_wmi_wmistat_read,
166 	.d_name = "wmistat",
167 };
168 
169 
170 static device_method_t acpi_wmi_methods[] = {
171 	/* Device interface */
172 	DEVMETHOD(device_probe,	acpi_wmi_probe),
173 	DEVMETHOD(device_attach, acpi_wmi_attach),
174 	DEVMETHOD(device_detach, acpi_wmi_detach),
175 
176 	/* bus interface */
177 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
178 	DEVMETHOD(bus_print_child,	bus_generic_print_child),
179 
180 	/* acpi_wmi interface */
181 	DEVMETHOD(acpi_wmi_provides_guid_string,
182 		    acpi_wmi_provides_guid_string_method),
183 	DEVMETHOD(acpi_wmi_evaluate_call, acpi_wmi_evaluate_call_method),
184 	DEVMETHOD(acpi_wmi_install_event_handler,
185 		    acpi_wmi_install_event_handler_method),
186 	DEVMETHOD(acpi_wmi_remove_event_handler,
187 		    acpi_wmi_remove_event_handler_method),
188 	DEVMETHOD(acpi_wmi_get_event_data, acpi_wmi_get_event_data_method),
189 	DEVMETHOD(acpi_wmi_get_block, acpi_wmi_get_block_method),
190 	DEVMETHOD(acpi_wmi_set_block, acpi_wmi_set_block_method),
191 
192 	{0, 0}
193 };
194 
195 static driver_t acpi_wmi_driver = {
196 	"acpi_wmi",
197 	acpi_wmi_methods,
198 	sizeof(struct acpi_wmi_softc),
199 };
200 
201 static devclass_t acpi_wmi_devclass;
202 DRIVER_MODULE(acpi_wmi, acpi, acpi_wmi_driver, acpi_wmi_devclass, 0, 0);
203 MODULE_VERSION(acpi_wmi, 1);
204 MODULE_DEPEND(acpi_wmi, acpi, 1, 1, 1);
205 static char *wmi_ids[] = {"PNP0C14", NULL};
206 
207 /*
208  * Probe for the PNP0C14 ACPI node
209  */
210 static int
211 acpi_wmi_probe(device_t dev)
212 {
213 	if (acpi_disabled("wmi") ||
214 	    ACPI_ID_PROBE(device_get_parent(dev), dev, wmi_ids) == NULL)
215 		return (ENXIO);
216 	device_set_desc(dev, "ACPI-WMI mapping");
217 
218 	return (0);
219 }
220 
221 /*
222  * Attach the device by:
223  * - Looking for the first ACPI EC device
224  * - Install the notify handler
225  * - Install the EC address space handler
226  * - Look for the _WDG node and read GUID information blocks
227  */
228 static int
229 acpi_wmi_attach(device_t dev)
230 {
231 	struct acpi_wmi_softc *sc;
232 	int ret;
233 	ACPI_STATUS status;
234 
235 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
236 	sc = device_get_softc(dev);
237 	ret = ENXIO;
238 
239 	ACPI_SERIAL_BEGIN(acpi_wmi);
240 	sc->wmi_dev = dev;
241 	sc->wmi_handle = acpi_get_handle(dev);
242 	TAILQ_INIT(&wmi_info_list);
243 	/* XXX Only works with one EC, but nearly all systems only have one. */
244 	if ((sc->ec_dev = devclass_get_device(devclass_find("acpi_ec"), 0))
245 	    == NULL)
246 		device_printf(dev, "cannot find EC device\n");
247 	else if (ACPI_FAILURE((status = AcpiInstallNotifyHandler(sc->wmi_handle,
248 		    ACPI_DEVICE_NOTIFY, acpi_wmi_notify_handler, sc))))
249 		device_printf(sc->wmi_dev, "couldn't install notify handler - %s\n",
250 		    AcpiFormatException(status));
251 	else if (ACPI_FAILURE((status = AcpiInstallAddressSpaceHandler(
252 		    sc->wmi_handle, ACPI_ADR_SPACE_EC, acpi_wmi_ec_handler,
253 		    NULL, sc)))) {
254 		device_printf(sc->wmi_dev, "couldn't install EC handler - %s\n",
255 		    AcpiFormatException(status));
256 		AcpiRemoveNotifyHandler(sc->wmi_handle, ACPI_DEVICE_NOTIFY,
257 		    acpi_wmi_notify_handler);
258 	} else if (ACPI_FAILURE((status = acpi_wmi_read_wdg_blocks(
259 		    sc->wmi_handle)))) {
260 		device_printf(sc->wmi_dev, "couldn't parse _WDG - %s\n",
261 		    AcpiFormatException(status));
262 		AcpiRemoveNotifyHandler(sc->wmi_handle, ACPI_DEVICE_NOTIFY,
263 		    acpi_wmi_notify_handler);
264 		AcpiRemoveAddressSpaceHandler(sc->wmi_handle, ACPI_ADR_SPACE_EC,
265 		    acpi_wmi_ec_handler);
266 	} else {
267 		sc->wmistat_dev_t = make_dev(&wmistat_cdevsw, 0, UID_ROOT,
268 		    GID_WHEEL, 0644, "wmistat");
269 		sc->wmistat_dev_t->si_drv1 = sc;
270 		sc->wmistat_open_pid = 0;
271 		sc->wmistat_bufptr = -1;
272 		ret = 0;
273 	}
274 	ACPI_SERIAL_END(acpi_wmi);
275 
276 	if (ret == 0) {
277 		bus_generic_probe(dev);
278 		ret = bus_generic_attach(dev);
279 	}
280 
281 	return (ret);
282 }
283 
284 /*
285  * Detach the driver by:
286  * - Removing notification handler
287  * - Removing address space handler
288  * - Turning off event generation for all WExx event activated by
289  *   child drivers
290  */
291 static int
292 acpi_wmi_detach(device_t dev)
293 {
294 	struct wmi_info *winfo, *tmp;
295 	struct acpi_wmi_softc *sc;
296 	int ret;
297 
298 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
299 	sc = device_get_softc(dev);
300 	ACPI_SERIAL_BEGIN(acpi_wmi);
301 
302 	if (sc->wmistat_open_pid != 0) {
303 		ret = EBUSY;
304 	} else {
305 		AcpiRemoveNotifyHandler(sc->wmi_handle, ACPI_DEVICE_NOTIFY,
306 		    acpi_wmi_notify_handler);
307 		AcpiRemoveAddressSpaceHandler(sc->wmi_handle,
308 		    ACPI_ADR_SPACE_EC, acpi_wmi_ec_handler);
309 		TAILQ_FOREACH_SAFE(winfo, &wmi_info_list, wmi_list, tmp) {
310 			if (winfo->event_handler)
311 				acpi_wmi_toggle_we_event_generation(dev,
312 				    winfo, EVENT_GENERATION_OFF);
313 			TAILQ_REMOVE(&wmi_info_list, winfo, wmi_list);
314 			free(winfo, M_ACPIWMI);
315 		}
316 		if (sc->wmistat_bufptr != -1) {
317 			sbuf_delete(&sc->wmistat_sbuf);
318 			sc->wmistat_bufptr = -1;
319 		}
320 		sc->wmistat_open_pid = 0;
321 		destroy_dev(sc->wmistat_dev_t);
322 		ret = 0;
323 	}
324 	ACPI_SERIAL_END(acpi_wmi);
325 
326 	return (ret);
327 }
328 
329 
330 /*
331  * Check if the given GUID string (human readable format
332  * AABBCCDD-EEFF-GGHH-IIJJ-KKLLMMNNOOPP)
333  * exists within _WDG
334  */
335 static int
336 acpi_wmi_provides_guid_string_method(device_t dev, const char *guid_string)
337 {
338 	struct wmi_info *winfo;
339 	int ret;
340 
341 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
342 	ACPI_SERIAL_BEGIN(acpi_wmi);
343 	winfo = acpi_wmi_lookup_wmi_info_by_guid_string(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(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 wmi_info *winfo;
412 	ACPI_STATUS status;
413 
414 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
415 
416 	status = AE_OK;
417 	ACPI_SERIAL_BEGIN(acpi_wmi);
418 	if (guid_string == NULL || event_handler == NULL)
419 		status = AE_BAD_PARAMETER;
420 	else if ((winfo = acpi_wmi_lookup_wmi_info_by_guid_string(guid_string))
421 		    == NULL)
422 		status = AE_NOT_EXIST;
423 	else if (winfo->event_handler != NULL ||
424 		(status = acpi_wmi_toggle_we_event_generation(dev, winfo,
425 		    EVENT_GENERATION_ON)) == AE_OK) {
426 		winfo->event_handler = event_handler;
427 		winfo->event_handler_user_data = data;
428 	}
429 	ACPI_SERIAL_END(acpi_wmi);
430 
431 	return (status);
432 }
433 
434 /*
435  * Remove a previously installed event handler from the given GUID
436  * If there was none installed, this call is silently discarded and
437  * reported as AE_OK
438  */
439 static ACPI_STATUS
440 acpi_wmi_remove_event_handler_method(device_t dev, const char *guid_string)
441 {
442 	struct wmi_info *winfo;
443 	ACPI_STATUS status;
444 
445 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
446 
447 	status = AE_OK;
448 	ACPI_SERIAL_BEGIN(acpi_wmi);
449 	if (guid_string &&
450 	    (winfo = acpi_wmi_lookup_wmi_info_by_guid_string(guid_string))
451 	    != NULL && winfo->event_handler) {
452 		status = acpi_wmi_toggle_we_event_generation(dev, winfo,
453 			    EVENT_GENERATION_OFF);
454 		winfo->event_handler = NULL;
455 		winfo->event_handler_user_data = NULL;
456 	}
457 	ACPI_SERIAL_END(acpi_wmi);
458 
459 	return (status);
460 }
461 
462 /*
463  * Get details on an event received through a callback registered
464  * through ACPI_WMI_REMOVE_EVENT_HANDLER into a user provided output buffer.
465  * (event_id equals "notify" passed in the callback)
466  */
467 static ACPI_STATUS
468 acpi_wmi_get_event_data_method(device_t dev, UINT32 event_id, ACPI_BUFFER *out)
469 {
470 	ACPI_OBJECT_LIST input;
471 	ACPI_OBJECT params[1];
472 	struct acpi_wmi_softc *sc;
473 	struct wmi_info *winfo;
474 	ACPI_STATUS status;
475 
476 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
477 
478 	sc = device_get_softc(dev);
479 	status = AE_NOT_FOUND;
480 	ACPI_SERIAL_BEGIN(acpi_wmi);
481 	params[0].Type = ACPI_TYPE_INTEGER;
482 	params[0].Integer.Value = event_id;
483 	input.Pointer = params;
484 	input.Count = 1;
485 	TAILQ_FOREACH(winfo, &wmi_info_list, wmi_list) {
486 		if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) &&
487 		    ((UINT8) winfo->ginfo.oid[0] == event_id)) {
488 			status = AcpiEvaluateObject(sc->wmi_handle, "_WED",
489 				    &input, out);
490 			break;
491 		}
492 	}
493 	ACPI_SERIAL_END(acpi_wmi);
494 
495 	return (status);
496 }
497 
498 /*
499  * Read a block of data from the given GUID (using WQxx (query))
500  * Will be returned in a user provided buffer (out).
501  * If the method is marked as expensive (ACPI_WMI_REGFLAG_EXPENSIVE)
502  * we will first call the WCxx control method to lock the node to
503  * lock the node for data collection and release it afterwards.
504  * (Failed WCxx calls are ignored to "support" broken implementations)
505  */
506 static ACPI_STATUS
507 acpi_wmi_get_block_method(device_t dev, const char *guid_string, UINT8 instance,
508 	ACPI_BUFFER *out)
509 {
510 	char wc_method[5] = "WCxx";
511 	char wq_method[5] = "WQxx";
512 	ACPI_OBJECT_LIST wc_input;
513 	ACPI_OBJECT_LIST wq_input;
514 	ACPI_OBJECT wc_params[1];
515 	ACPI_OBJECT wq_params[1];
516 	ACPI_HANDLE wc_handle;
517 	struct acpi_wmi_softc *sc;
518 	struct wmi_info *winfo;
519 	ACPI_STATUS status;
520 	ACPI_STATUS wc_status;
521 
522 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
523 
524 	sc = device_get_softc(dev);
525 	wc_status = AE_ERROR;
526 	ACPI_SERIAL_BEGIN(acpi_wmi);
527 	if (guid_string == NULL || out == NULL)
528 		status = AE_BAD_PARAMETER;
529 	else if ((winfo = acpi_wmi_lookup_wmi_info_by_guid_string(guid_string))
530 		    == NULL)
531 		status = AE_ERROR;
532 	else if (instance > winfo->ginfo.max_instance)
533 		status = AE_BAD_PARAMETER;
534 	else if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) ||
535 	    (winfo->ginfo.flags & ACPI_WMI_REGFLAG_METHOD))
536 		status = AE_ERROR;
537 	else {
538 		wq_params[0].Type = ACPI_TYPE_INTEGER;
539 		wq_params[0].Integer.Value = instance;
540 		wq_input.Pointer = wq_params;
541 		wq_input.Count = 1;
542 		if (winfo->ginfo.flags & ACPI_WMI_REGFLAG_EXPENSIVE) {
543 			wc_params[0].Type = ACPI_TYPE_INTEGER;
544 			wc_params[0].Integer.Value = 1;
545 			wc_input.Pointer = wc_params;
546 			wc_input.Count = 1;
547 			wc_method[2] = winfo->ginfo.oid[0];
548 			wc_method[3] = winfo->ginfo.oid[1];
549 			wc_status = AcpiGetHandle(sc->wmi_handle, wc_method,
550 				    &wc_handle);
551 			if (ACPI_SUCCESS(wc_status))
552 				wc_status = AcpiEvaluateObject(wc_handle,
553 						wc_method, &wc_input, NULL);
554 		}
555 		wq_method[2] = winfo->ginfo.oid[0];
556 		wq_method[3] = winfo->ginfo.oid[1];
557 		status = AcpiEvaluateObject(sc->wmi_handle, wq_method,
558 			    &wq_input, out);
559 		if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EXPENSIVE)
560 		    && ACPI_SUCCESS(wc_status)) {
561 			wc_params[0].Integer.Value = 0;
562 			status = AcpiEvaluateObject(wc_handle, wc_method,
563 				    &wc_input, NULL);  /* XXX this might be
564 				    			 the wrong status to
565 				    			 return? */
566 		}
567 	}
568 	ACPI_SERIAL_END(acpi_wmi);
569 
570 	return (status);
571 }
572 
573 /*
574  * Write a block of data to the given GUID (using WSxx)
575  */
576 static ACPI_STATUS
577 acpi_wmi_set_block_method(device_t dev, const char *guid_string, UINT8 instance,
578 	const ACPI_BUFFER *in)
579 {
580 	char method[5] = "WSxx";
581 	ACPI_OBJECT_LIST input;
582 	ACPI_OBJECT params[2];
583 	struct wmi_info *winfo;
584 	struct acpi_wmi_softc *sc;
585 	ACPI_STATUS status;
586 
587 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
588 
589 	sc = device_get_softc(dev);
590 	ACPI_SERIAL_BEGIN(acpi_wmi);
591 	if (guid_string == NULL || in == NULL)
592 		status = AE_BAD_DATA;
593 	else if ((winfo = acpi_wmi_lookup_wmi_info_by_guid_string(guid_string))
594 		    == NULL)
595 		status = AE_ERROR;
596 	else if (instance > winfo->ginfo.max_instance)
597 		status = AE_BAD_PARAMETER;
598 	else if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) ||
599 		    (winfo->ginfo.flags & ACPI_WMI_REGFLAG_METHOD))
600 		status = AE_ERROR;
601 	else {
602 		params[0].Type = ACPI_TYPE_INTEGER;
603 		params[0].Integer.Value = instance;
604 		input.Pointer = params;
605 		input.Count = 2;
606 		params[1].Type = (winfo->ginfo.flags & ACPI_WMI_REGFLAG_STRING)
607 		    ?ACPI_TYPE_STRING:ACPI_TYPE_BUFFER;
608 		params[1].Buffer.Length = in->Length;
609 		params[1].Buffer.Pointer = in->Pointer;
610 		method[2] = winfo->ginfo.oid[0];
611 		method[3] = winfo->ginfo.oid[1];
612 		status = AcpiEvaluateObject(sc->wmi_handle, method,
613 			    &input, NULL);
614 	}
615 	ACPI_SERIAL_END(acpi_wmi);
616 
617 	return (status);
618 }
619 
620 /*
621  * Handle events received and dispatch them to
622  * stakeholders that registered through ACPI_WMI_INSTALL_EVENT_HANDLER
623  */
624 static void
625 acpi_wmi_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
626 {
627 	ACPI_NOTIFY_HANDLER handler;
628 	void *handler_data;
629 	struct wmi_info *winfo;
630 
631 	ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, notify);
632 
633 	handler = NULL;
634 	handler_data = NULL;
635 	ACPI_SERIAL_BEGIN(acpi_wmi);
636 	TAILQ_FOREACH(winfo, &wmi_info_list, wmi_list) {
637 		if ((winfo->ginfo.flags & ACPI_WMI_REGFLAG_EVENT) &&
638 				((UINT8) winfo->ginfo.oid[0] == notify)) {
639 			if (winfo->event_handler) {
640 				handler = winfo->event_handler;
641 				handler_data = winfo->event_handler_user_data;
642 				break;
643 			}
644 		}
645 	}
646 	ACPI_SERIAL_END(acpi_wmi);
647 	if (handler) {
648 		handler(h, notify, handler_data);
649 	}
650 }
651 
652 /*
653  * Handle EC address space notifications reveived on the WDG node
654  * (this mimics EcAddressSpaceHandler in acpi_ec.c)
655  */
656 static ACPI_STATUS
657 acpi_wmi_ec_handler(UINT32 function, ACPI_PHYSICAL_ADDRESS address,
658     UINT32 width, UINT64 *value, void *context,
659     void *region_context)
660 {
661 	struct acpi_wmi_softc *sc;
662 	int i;
663 	UINT64 ec_data;
664 	UINT8 ec_addr;
665 	ACPI_STATUS status;
666 
667 	ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, (UINT32)address);
668 
669 	sc = (struct acpi_wmi_softc *)context;
670 	if (width % 8 != 0 || value == NULL || context == NULL)
671 		return (AE_BAD_PARAMETER);
672 	if (address + (width / 8) - 1 > 0xFF)
673 		return (AE_BAD_ADDRESS);
674 	if (function == ACPI_READ)
675 		*value = 0;
676 	ec_addr = address;
677 	status = AE_ERROR;
678 
679 	for (i = 0; i < width; i += 8, ++ec_addr) {
680 		switch (function) {
681 		case ACPI_READ:
682 			status = ACPI_EC_READ(sc->ec_dev, ec_addr, &ec_data, 1);
683 			if (ACPI_SUCCESS(status))
684 				*value |= ((UINT64)ec_data) << i;
685 		break;
686 		case ACPI_WRITE:
687 			ec_data = (UINT8)((*value) >> i);
688 			status = ACPI_EC_WRITE(sc->ec_dev, ec_addr, ec_data, 1);
689 			break;
690 		default:
691 			device_printf(sc->wmi_dev,
692 			    "invalid acpi_wmi_ec_handler function %d\n",
693 			    function);
694 			status = AE_BAD_PARAMETER;
695 			break;
696 		}
697 		if (ACPI_FAILURE(status))
698 			break;
699 	}
700 
701 	return (status);
702 }
703 
704 /*
705  * Read GUID blocks from the _WDG node
706  * into wmi_info_list.
707  */
708 static ACPI_STATUS
709 acpi_wmi_read_wdg_blocks(ACPI_HANDLE h)
710 {
711 	ACPI_BUFFER out = {ACPI_ALLOCATE_BUFFER, NULL};
712 	struct guid_info *ginfo;
713 	ACPI_OBJECT *obj;
714 	struct wmi_info *winfo;
715 	UINT32 i;
716 	UINT32 wdg_block_count;
717 	ACPI_STATUS status;
718 
719 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
720 
721 	ACPI_SERIAL_ASSERT(acpi_wmi);
722 	if (ACPI_FAILURE(status = AcpiEvaluateObject(h, "_WDG", NULL, &out)))
723 		return (status);
724 	obj = (ACPI_OBJECT*) out.Pointer;
725 	wdg_block_count = obj->Buffer.Length / sizeof(struct guid_info);
726 	if ((ginfo = malloc(obj->Buffer.Length, M_ACPIWMI, M_NOWAIT))
727 		    == NULL) {
728 		AcpiOsFree(out.Pointer);
729 		return (AE_NO_MEMORY);
730 	}
731 	memcpy(ginfo, obj->Buffer.Pointer, obj->Buffer.Length);
732 	for (i = 0; i < wdg_block_count; ++i) {
733 		if ((winfo = malloc(sizeof(struct wmi_info), M_ACPIWMI,
734 			    M_NOWAIT | M_ZERO)) == NULL) {
735 			AcpiOsFree(out.Pointer);
736 			free(ginfo, M_ACPIWMI);
737 			return (AE_NO_MEMORY);
738 		}
739 		winfo->ginfo = ginfo[i];
740 		TAILQ_INSERT_TAIL(&wmi_info_list, winfo, wmi_list);
741 	}
742 	AcpiOsFree(out.Pointer);
743 	free(ginfo, M_ACPIWMI);
744 
745 	return (status);
746 }
747 
748 /*
749  * Toggle event generation in for the given GUID (passed by winfo)
750  * Turn on to get notified (through acpi_wmi_notify_handler) if events happen
751  * on the given GUID.
752  */
753 static ACPI_STATUS
754 acpi_wmi_toggle_we_event_generation(device_t dev, struct wmi_info *winfo,
755     enum event_generation_state state)
756 {
757 	char method[5] = "WExx";
758 	ACPI_OBJECT_LIST input;
759 	ACPI_OBJECT params[1];
760 	struct acpi_wmi_softc *sc;
761 	ACPI_STATUS status;
762 
763 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
764 
765 	sc = device_get_softc(dev);
766 	ACPI_SERIAL_ASSERT(acpi_wmi);
767 	params[0].Type = ACPI_TYPE_INTEGER;
768 	params[0].Integer.Value = state==EVENT_GENERATION_ON?1:0;
769 	input.Pointer = params;
770 	input.Count = 1;
771 
772 	UINT8 hi = ((UINT8) winfo->ginfo.oid[0]) >> 4;
773 	UINT8 lo = ((UINT8) winfo->ginfo.oid[0]) & 0xf;
774 	method[2] = (hi > 9 ? hi + 55: hi + 48);
775 	method[3] = (lo > 9 ? lo + 55: lo + 48);
776 	status = AcpiEvaluateObject(sc->wmi_handle, method, &input, NULL);
777 	if (status == AE_NOT_FOUND) status = AE_OK;
778 
779 	return (status);
780 }
781 
782 /*
783  * Convert given two digit hex string (hexin) to an UINT8 referenced
784  * by byteout.
785  * Return != 0 if the was a problem (invalid input)
786  */
787 static __inline int acpi_wmi_hex_to_int(const UINT8 *hexin, UINT8 *byteout)
788 {
789 	unsigned int hi;
790 	unsigned int lo;
791 
792 	hi = hexin[0];
793 	lo = hexin[1];
794 	if ('0' <= hi && hi <= '9')
795 		hi -= '0';
796 	else if ('A' <= hi && hi <= 'F')
797 		hi -= ('A' - 10);
798 	else if ('a' <= hi && hi <= 'f')
799 		hi -= ('a' - 10);
800 	else
801 		return (1);
802 	if ('0' <= lo && lo <= '9')
803 		lo -= '0';
804 	else if ('A' <= lo && lo <= 'F')
805 		lo -= ('A' - 10);
806 	else if ('a' <= lo && lo <= 'f')
807 		lo -= ('a' - 10);
808 	else
809 		return (1);
810 	*byteout = (hi << 4) + lo;
811 
812 	return (0);
813 }
814 
815 /*
816  * Convert a human readable 36 character GUID into a 16byte
817  * machine readable one.
818  * The basic algorithm looks as follows:
819  * Input:  AABBCCDD-EEFF-GGHH-IIJJ-KKLLMMNNOOPP
820  * Output: DCBAFEHGIJKLMNOP
821  * (AA BB CC etc. represent two digit hex numbers == bytes)
822  * Return != 0 if passed guid string is invalid
823  */
824 static int
825 acpi_wmi_guid_string_to_guid(const UINT8 *guid_string, UINT8 *guid)
826 {
827 	static const int mapping[20] = {3, 2, 1, 0, -1, 5, 4, -1, 7, 6, -1,
828 	    8, 9, -1, 10, 11, 12, 13, 14, 15};
829 	int i;
830 
831 	for (i = 0; i < 20; ++i, ++guid_string) {
832 		if (mapping[i] >= 0) {
833 			if (acpi_wmi_hex_to_int(guid_string,
834 			    &guid[mapping[i]]))
835 				return (-1);
836 			++guid_string;
837 		} else if (*guid_string != '-')
838 			return (-1);
839 	}
840 
841 	return (0);
842 }
843 
844 /*
845  * Lookup a wmi_info structure in wmi_list based on a
846  * human readable GUID
847  * Return NULL if the GUID is unknown in the _WDG
848  */
849 static struct wmi_info*
850 acpi_wmi_lookup_wmi_info_by_guid_string(const char *guid_string)
851 {
852 	char guid[16];
853 	struct wmi_info *winfo;
854 
855 	ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
856 
857 	ACPI_SERIAL_ASSERT(acpi_wmi);
858 
859 	if (!acpi_wmi_guid_string_to_guid(guid_string, guid)) {
860 		TAILQ_FOREACH(winfo, &wmi_info_list, wmi_list) {
861 			if (!memcmp(winfo->ginfo.guid, guid, 16)) {
862 				return (winfo);
863 			}
864 		}
865 	}
866 
867 	return (NULL);
868 }
869 
870 /*
871  * open wmistat device
872  */
873 static int
874 acpi_wmi_wmistat_open(struct cdev* dev, int flags, int mode, struct thread *td)
875 {
876 	struct acpi_wmi_softc *sc;
877 	int ret;
878 
879 	if (dev == NULL || dev->si_drv1 == NULL)
880 		return (EBADF);
881 	sc = dev->si_drv1;
882 
883 	ACPI_SERIAL_BEGIN(acpi_wmi);
884 	if (sc->wmistat_open_pid != 0) {
885 		ret = EBUSY;
886 	}
887 	else {
888 		if (sbuf_new(&sc->wmistat_sbuf, NULL, 4096, SBUF_AUTOEXTEND)
889 			    == NULL) {
890 			ret = ENXIO;
891 		} else {
892 			sc->wmistat_open_pid = td->td_proc->p_pid;
893 			sc->wmistat_bufptr = 0;
894 			ret = 0;
895 		}
896 	}
897 	ACPI_SERIAL_END(acpi_wmi);
898 
899 	return (ret);
900 }
901 
902 /*
903  * close wmistat device
904  */
905 static int
906 acpi_wmi_wmistat_close(struct cdev* dev, int flags, int mode,
907     struct thread *td)
908 {
909 	struct acpi_wmi_softc *sc;
910 	int ret;
911 
912 	if (dev == NULL || dev->si_drv1 == NULL)
913 		return (EBADF);
914 	sc = dev->si_drv1;
915 
916 	ACPI_SERIAL_BEGIN(acpi_wmi);
917 	if (sc->wmistat_open_pid == 0) {
918 		ret = EBADF;
919 	}
920 	else {
921 		if (sc->wmistat_bufptr != -1) {
922 			sbuf_delete(&sc->wmistat_sbuf);
923 			sc->wmistat_bufptr = -1;
924 		}
925 		sc->wmistat_open_pid = 0;
926 		ret = 0;
927 	}
928 	ACPI_SERIAL_END(acpi_wmi);
929 
930 	return (ret);
931 }
932 
933 /*
934  * Read from wmistat guid information
935  */
936 static int
937 acpi_wmi_wmistat_read(struct cdev *dev, struct uio *buf, int flag)
938 {
939 	struct acpi_wmi_softc *sc;
940 	struct wmi_info *winfo;
941 	int l;
942 	int ret;
943 	UINT8* guid;
944 
945 	if (dev == NULL || dev->si_drv1 == NULL)
946 		return (EBADF);
947 	sc = dev->si_drv1;
948 
949 	ACPI_SERIAL_BEGIN(acpi_wmi);
950 	if (sc->wmistat_open_pid != buf->uio_td->td_proc->p_pid ||
951 			sc->wmistat_bufptr == -1) {
952 		ret = EBADF;
953 	}
954 	else {
955 		if (!sbuf_done(&sc->wmistat_sbuf)) {
956 			sbuf_printf(&sc->wmistat_sbuf, "GUID                 "
957 				    "                 INST EXPE METH STR "
958 				    "EVENT OID\n");
959 			TAILQ_FOREACH(winfo, &wmi_info_list, wmi_list) {
960 				guid = (UINT8*)winfo->ginfo.guid;
961 				sbuf_printf(&sc->wmistat_sbuf,
962 					    "{%02X%02X%02X%02X-%02X%02X-"
963 					    "%02X%02X-%02X%02X-%02X%02X"
964 					    "%02X%02X%02X%02X} %3d %-5s",
965 					guid[3], guid[2], guid[1], guid[0],
966 					guid[5], guid[4],
967 					guid[7], guid[6],
968 					guid[8], guid[9],
969 					guid[10], guid[11], guid[12],
970 					guid[13], guid[14], guid[15],
971 					winfo->ginfo.max_instance,
972 					(winfo->ginfo.flags&
973 						ACPI_WMI_REGFLAG_EXPENSIVE)?
974 						"YES":"NO"
975 					);
976 				if (winfo->ginfo.flags&ACPI_WMI_REGFLAG_METHOD)
977 					sbuf_printf(&sc->wmistat_sbuf,
978 						    "WM%c%c ",
979 						    winfo->ginfo.oid[0],
980 						    winfo->ginfo.oid[1]);
981 				else
982 					sbuf_printf(&sc->wmistat_sbuf, "NO   ");
983 				sbuf_printf(&sc->wmistat_sbuf, "%-4s",
984 					    (winfo->ginfo.flags&
985 					    ACPI_WMI_REGFLAG_STRING)?"YES":"NO"
986 					);
987 				if (winfo->ginfo.flags&ACPI_WMI_REGFLAG_EVENT)
988 					sbuf_printf(&sc->wmistat_sbuf,
989 						    "0x%02X%s -\n",
990 						    (UINT8)winfo->ginfo.oid[0],
991 						    winfo->event_handler==NULL?
992 						    " ":"+");
993 				else
994 					sbuf_printf(&sc->wmistat_sbuf,
995 						    "NO    %c%c\n",
996 						    winfo->ginfo.oid[0],
997 						    winfo->ginfo.oid[1]);
998 			}
999 			sbuf_finish(&sc->wmistat_sbuf);
1000 		}
1001 		if (sbuf_len(&sc->wmistat_sbuf) <= 0) {
1002 			sbuf_delete(&sc->wmistat_sbuf);
1003 			sc->wmistat_bufptr = -1;
1004 			sc->wmistat_open_pid = 0;
1005 			ret = ENOMEM;
1006 		} else {
1007 			l = min(buf->uio_resid, sbuf_len(&sc->wmistat_sbuf) -
1008 				    sc->wmistat_bufptr);
1009 			ret = (l > 0)?uiomove(sbuf_data(&sc->wmistat_sbuf) +
1010 				    sc->wmistat_bufptr, l, buf) : 0;
1011 			sc->wmistat_bufptr += l;
1012 		}
1013 	}
1014 	ACPI_SERIAL_END(acpi_wmi);
1015 
1016 	return (ret);
1017 }
1018