2 * ACPI-WMI mapping driver
4 * Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
6 * GUID parsing code from ldm.c is:
7 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
8 * Copyright (c) 2001-2007 Anton Altaparmakov
9 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
23 * You should have received a copy of the GNU General Public License along
24 * with this program; if not, write to the Free Software Foundation, Inc.,
25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
27 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
30 #include <linux/kernel.h>
31 #include <linux/init.h>
32 #include <linux/types.h>
33 #include <linux/list.h>
34 #include <linux/acpi.h>
35 #include <acpi/acpi_bus.h>
36 #include <acpi/acpi_drivers.h>
38 ACPI_MODULE_NAME("wmi");
39 MODULE_AUTHOR("Carlos Corbacho");
40 MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
41 MODULE_LICENSE("GPL");
43 #define ACPI_WMI_CLASS "wmi"
45 #define PREFIX "ACPI: WMI: "
47 static DEFINE_MUTEX(wmi_data_lock);
54 unsigned char notify_id;
55 unsigned char reserved;
63 struct list_head list;
64 struct guid_block gblock;
66 wmi_notify_handler handler;
70 static struct wmi_block wmi_blocks;
73 * If the GUID data block is marked as expensive, we must enable and
74 * explicitily disable data collection.
76 #define ACPI_WMI_EXPENSIVE 0x1
77 #define ACPI_WMI_METHOD 0x2 /* GUID is a method */
78 #define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
79 #define ACPI_WMI_EVENT 0x8 /* GUID is an event */
81 static int acpi_wmi_remove(struct acpi_device *device, int type);
82 static int acpi_wmi_add(struct acpi_device *device);
83 static void acpi_wmi_notify(struct acpi_device *device, u32 event);
85 static const struct acpi_device_id wmi_device_ids[] = {
90 MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
92 static struct acpi_driver acpi_wmi_driver = {
94 .class = ACPI_WMI_CLASS,
95 .ids = wmi_device_ids,
98 .remove = acpi_wmi_remove,
99 .notify = acpi_wmi_notify,
104 * GUID parsing functions
108 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
109 * @src: Pointer to at least 2 characters to convert.
111 * Convert a two character ASCII hex string to a number.
113 * Return: 0-255 Success, the byte was parsed correctly
114 * -1 Error, an invalid character was supplied
116 static int wmi_parse_hexbyte(const u8 *src)
118 unsigned int x; /* For correct wrapping */
123 if (x - '0' <= '9' - '0') {
125 } else if (x - 'a' <= 'f' - 'a') {
127 } else if (x - 'A' <= 'F' - 'A') {
136 if (x - '0' <= '9' - '0')
137 return h | (x - '0');
138 if (x - 'a' <= 'f' - 'a')
139 return h | (x - 'a' + 10);
140 if (x - 'A' <= 'F' - 'A')
141 return h | (x - 'A' + 10);
146 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
147 * @src: Memory block holding binary GUID (16 bytes)
148 * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
150 * Byte swap a binary GUID to match it's real GUID value
152 static void wmi_swap_bytes(u8 *src, u8 *dest)
156 for (i = 0; i <= 3; i++)
157 memcpy(dest + i, src + (3 - i), 1);
159 for (i = 0; i <= 1; i++)
160 memcpy(dest + 4 + i, src + (5 - i), 1);
162 for (i = 0; i <= 1; i++)
163 memcpy(dest + 6 + i, src + (7 - i), 1);
165 memcpy(dest + 8, src + 8, 8);
169 * wmi_parse_guid - Convert GUID from ASCII to binary
170 * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
171 * @dest: Memory block to hold binary GUID (16 bytes)
173 * N.B. The GUID need not be NULL terminated.
175 * Return: 'true' @dest contains binary GUID
176 * 'false' @dest contents are undefined
178 static bool wmi_parse_guid(const u8 *src, u8 *dest)
180 static const int size[] = { 4, 2, 2, 2, 6 };
183 if (src[8] != '-' || src[13] != '-' ||
184 src[18] != '-' || src[23] != '-')
187 for (j = 0; j < 5; j++, src++) {
188 for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) {
189 v = wmi_parse_hexbyte(src);
198 static bool find_guid(const char *guid_string, struct wmi_block **out)
200 char tmp[16], guid_input[16];
201 struct wmi_block *wblock;
202 struct guid_block *block;
205 wmi_parse_guid(guid_string, tmp);
206 wmi_swap_bytes(tmp, guid_input);
208 list_for_each(p, &wmi_blocks.list) {
209 wblock = list_entry(p, struct wmi_block, list);
210 block = &wblock->gblock;
212 if (memcmp(block->guid, guid_input, 16) == 0) {
221 static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
223 struct guid_block *block = NULL;
225 struct acpi_object_list input;
226 union acpi_object params[1];
230 block = &wblock->gblock;
231 handle = wblock->handle;
237 input.pointer = params;
238 params[0].type = ACPI_TYPE_INTEGER;
239 params[0].integer.value = enable;
241 snprintf(method, 5, "WE%02X", block->notify_id);
242 status = acpi_evaluate_object(handle, method, &input, NULL);
244 if (status != AE_OK && status != AE_NOT_FOUND)
251 * Exported WMI functions
254 * wmi_evaluate_method - Evaluate a WMI method
255 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
256 * @instance: Instance index
257 * @method_id: Method ID to call
258 * &in: Buffer containing input for the method call
259 * &out: Empty buffer to return the method results
261 * Call an ACPI-WMI method
263 acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
264 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
266 struct guid_block *block = NULL;
267 struct wmi_block *wblock = NULL;
270 struct acpi_object_list input;
271 union acpi_object params[3];
272 char method[5] = "WM";
274 if (!find_guid(guid_string, &wblock))
277 block = &wblock->gblock;
278 handle = wblock->handle;
280 if (!(block->flags & ACPI_WMI_METHOD))
283 if (block->instance_count < instance)
284 return AE_BAD_PARAMETER;
287 input.pointer = params;
288 params[0].type = ACPI_TYPE_INTEGER;
289 params[0].integer.value = instance;
290 params[1].type = ACPI_TYPE_INTEGER;
291 params[1].integer.value = method_id;
296 if (block->flags & ACPI_WMI_STRING) {
297 params[2].type = ACPI_TYPE_STRING;
299 params[2].type = ACPI_TYPE_BUFFER;
301 params[2].buffer.length = in->length;
302 params[2].buffer.pointer = in->pointer;
305 strncat(method, block->object_id, 2);
307 status = acpi_evaluate_object(handle, method, &input, out);
311 EXPORT_SYMBOL_GPL(wmi_evaluate_method);
314 * wmi_query_block - Return contents of a WMI block
315 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
316 * @instance: Instance index
317 * &out: Empty buffer to return the contents of the data block to
319 * Return the contents of an ACPI-WMI data block to a buffer
321 acpi_status wmi_query_block(const char *guid_string, u8 instance,
322 struct acpi_buffer *out)
324 struct guid_block *block = NULL;
325 struct wmi_block *wblock = NULL;
326 acpi_handle handle, wc_handle;
327 acpi_status status, wc_status = AE_ERROR;
328 struct acpi_object_list input, wc_input;
329 union acpi_object wc_params[1], wq_params[1];
331 char wc_method[5] = "WC";
333 if (!guid_string || !out)
334 return AE_BAD_PARAMETER;
336 if (!find_guid(guid_string, &wblock))
339 block = &wblock->gblock;
340 handle = wblock->handle;
342 if (block->instance_count < instance)
343 return AE_BAD_PARAMETER;
345 /* Check GUID is a data block */
346 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
350 input.pointer = wq_params;
351 wq_params[0].type = ACPI_TYPE_INTEGER;
352 wq_params[0].integer.value = instance;
355 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
358 if (block->flags & ACPI_WMI_EXPENSIVE) {
360 wc_input.pointer = wc_params;
361 wc_params[0].type = ACPI_TYPE_INTEGER;
362 wc_params[0].integer.value = 1;
364 strncat(wc_method, block->object_id, 2);
367 * Some GUIDs break the specification by declaring themselves
368 * expensive, but have no corresponding WCxx method. So we
369 * should not fail if this happens.
371 wc_status = acpi_get_handle(handle, wc_method, &wc_handle);
372 if (ACPI_SUCCESS(wc_status))
373 wc_status = acpi_evaluate_object(handle, wc_method,
377 strcpy(method, "WQ");
378 strncat(method, block->object_id, 2);
380 status = acpi_evaluate_object(handle, method, &input, out);
383 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
384 * the WQxx method failed - we should disable collection anyway.
386 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
387 wc_params[0].integer.value = 0;
388 status = acpi_evaluate_object(handle,
389 wc_method, &wc_input, NULL);
394 EXPORT_SYMBOL_GPL(wmi_query_block);
397 * wmi_set_block - Write to a WMI block
398 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
399 * @instance: Instance index
400 * &in: Buffer containing new values for the data block
402 * Write the contents of the input buffer to an ACPI-WMI data block
404 acpi_status wmi_set_block(const char *guid_string, u8 instance,
405 const struct acpi_buffer *in)
407 struct guid_block *block = NULL;
408 struct wmi_block *wblock = NULL;
410 struct acpi_object_list input;
411 union acpi_object params[2];
412 char method[5] = "WS";
414 if (!guid_string || !in)
417 if (!find_guid(guid_string, &wblock))
420 block = &wblock->gblock;
421 handle = wblock->handle;
423 if (block->instance_count < instance)
424 return AE_BAD_PARAMETER;
426 /* Check GUID is a data block */
427 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
431 input.pointer = params;
432 params[0].type = ACPI_TYPE_INTEGER;
433 params[0].integer.value = instance;
435 if (block->flags & ACPI_WMI_STRING) {
436 params[1].type = ACPI_TYPE_STRING;
438 params[1].type = ACPI_TYPE_BUFFER;
440 params[1].buffer.length = in->length;
441 params[1].buffer.pointer = in->pointer;
443 strncat(method, block->object_id, 2);
445 return acpi_evaluate_object(handle, method, &input, NULL);
447 EXPORT_SYMBOL_GPL(wmi_set_block);
450 * wmi_install_notify_handler - Register handler for WMI events
451 * @handler: Function to handle notifications
452 * @data: Data to be returned to handler when event is fired
454 * Register a handler for events sent to the ACPI-WMI mapper device.
456 acpi_status wmi_install_notify_handler(const char *guid,
457 wmi_notify_handler handler, void *data)
459 struct wmi_block *block;
462 if (!guid || !handler)
463 return AE_BAD_PARAMETER;
465 find_guid(guid, &block);
470 return AE_ALREADY_ACQUIRED;
472 block->handler = handler;
473 block->handler_data = data;
475 status = wmi_method_enable(block, 1);
479 EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
482 * wmi_uninstall_notify_handler - Unregister handler for WMI events
484 * Unregister handler for events sent to the ACPI-WMI mapper device.
486 acpi_status wmi_remove_notify_handler(const char *guid)
488 struct wmi_block *block;
492 return AE_BAD_PARAMETER;
494 find_guid(guid, &block);
499 return AE_NULL_ENTRY;
501 status = wmi_method_enable(block, 0);
503 block->handler = NULL;
504 block->handler_data = NULL;
508 EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
511 * wmi_get_event_data - Get WMI data associated with an event
513 * @event - Event to find
514 * &out - Buffer to hold event data
516 * Returns extra data associated with an event in WMI.
518 acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
520 struct acpi_object_list input;
521 union acpi_object params[1];
522 struct guid_block *gblock;
523 struct wmi_block *wblock;
527 input.pointer = params;
528 params[0].type = ACPI_TYPE_INTEGER;
529 params[0].integer.value = event;
531 list_for_each(p, &wmi_blocks.list) {
532 wblock = list_entry(p, struct wmi_block, list);
533 gblock = &wblock->gblock;
535 if ((gblock->flags & ACPI_WMI_EVENT) &&
536 (gblock->notify_id == event))
537 return acpi_evaluate_object(wblock->handle, "_WED",
543 EXPORT_SYMBOL_GPL(wmi_get_event_data);
546 * wmi_has_guid - Check if a GUID is available
547 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
549 * Check if a given GUID is defined by _WDG
551 bool wmi_has_guid(const char *guid_string)
553 return find_guid(guid_string, NULL);
555 EXPORT_SYMBOL_GPL(wmi_has_guid);
558 * Parse the _WDG method for the GUID data blocks
560 static __init acpi_status parse_wdg(acpi_handle handle)
562 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
563 union acpi_object *obj;
564 struct guid_block *gblock;
565 struct wmi_block *wblock;
569 status = acpi_evaluate_object(handle, "_WDG", NULL, &out);
571 if (ACPI_FAILURE(status))
574 obj = (union acpi_object *) out.pointer;
576 if (obj->type != ACPI_TYPE_BUFFER)
579 total = obj->buffer.length / sizeof(struct guid_block);
581 gblock = kzalloc(obj->buffer.length, GFP_KERNEL);
585 memcpy(gblock, obj->buffer.pointer, obj->buffer.length);
587 for (i = 0; i < total; i++) {
588 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
592 wblock->gblock = gblock[i];
593 wblock->handle = handle;
594 list_add_tail(&wblock->list, &wmi_blocks.list);
604 * WMI can have EmbeddedControl access regions. In which case, we just want to
605 * hand these off to the EC driver.
608 acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
609 u32 bits, acpi_integer * value,
610 void *handler_context, void *region_context)
612 int result = 0, i = 0;
615 if ((address > 0xFF) || !value)
616 return AE_BAD_PARAMETER;
618 if (function != ACPI_READ && function != ACPI_WRITE)
619 return AE_BAD_PARAMETER;
622 return AE_BAD_PARAMETER;
624 if (function == ACPI_READ) {
625 result = ec_read(address, &temp);
626 (*value) |= ((acpi_integer)temp) << i;
628 temp = 0xff & ((*value) >> i);
629 result = ec_write(address, temp);
634 return AE_BAD_PARAMETER;
647 static void acpi_wmi_notify(struct acpi_device *device, u32 event)
649 struct guid_block *block;
650 struct wmi_block *wblock;
653 list_for_each(p, &wmi_blocks.list) {
654 wblock = list_entry(p, struct wmi_block, list);
655 block = &wblock->gblock;
657 if ((block->flags & ACPI_WMI_EVENT) &&
658 (block->notify_id == event)) {
660 wblock->handler(event, wblock->handler_data);
662 acpi_bus_generate_netlink_event(
663 device->pnp.device_class, dev_name(&device->dev),
670 static int acpi_wmi_remove(struct acpi_device *device, int type)
672 acpi_remove_address_space_handler(device->handle,
673 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
678 static int __init acpi_wmi_add(struct acpi_device *device)
683 status = acpi_install_address_space_handler(device->handle,
685 &acpi_wmi_ec_space_handler,
687 if (ACPI_FAILURE(status))
690 status = parse_wdg(device->handle);
691 if (ACPI_FAILURE(status)) {
692 printk(KERN_ERR PREFIX "Error installing EC region handler\n");
699 static int __init acpi_wmi_init(void)
703 INIT_LIST_HEAD(&wmi_blocks.list);
708 result = acpi_bus_register_driver(&acpi_wmi_driver);
711 printk(KERN_INFO PREFIX "Error loading mapper\n");
713 printk(KERN_INFO PREFIX "Mapper loaded\n");
719 static void __exit acpi_wmi_exit(void)
721 struct list_head *p, *tmp;
722 struct wmi_block *wblock;
724 acpi_bus_unregister_driver(&acpi_wmi_driver);
726 list_for_each_safe(p, tmp, &wmi_blocks.list) {
727 wblock = list_entry(p, struct wmi_block, list);
733 printk(KERN_INFO PREFIX "Mapper unloaded\n");
736 subsys_initcall(acpi_wmi_init);
737 module_exit(acpi_wmi_exit);