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"
46 #define PREFIX "ACPI: WMI: "
48 static DEFINE_MUTEX(wmi_data_lock
);
55 unsigned char notify_id
;
56 unsigned char reserved
;
64 struct list_head list
;
65 struct guid_block gblock
;
67 wmi_notify_handler handler
;
71 static struct wmi_block wmi_blocks
;
74 * If the GUID data block is marked as expensive, we must enable and
75 * explicitily disable data collection.
77 #define ACPI_WMI_EXPENSIVE 0x1
78 #define ACPI_WMI_METHOD 0x2 /* GUID is a method */
79 #define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
80 #define ACPI_WMI_EVENT 0x8 /* GUID is an event */
82 static int acpi_wmi_remove(struct acpi_device
*device
, int type
);
83 static int acpi_wmi_add(struct acpi_device
*device
);
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
,
103 * GUID parsing functions
107 * wmi_parse_hexbyte - Convert a ASCII hex number to a byte
108 * @src: Pointer to at least 2 characters to convert.
110 * Convert a two character ASCII hex string to a number.
112 * Return: 0-255 Success, the byte was parsed correctly
113 * -1 Error, an invalid character was supplied
115 static int wmi_parse_hexbyte(const u8
*src
)
117 unsigned int x
; /* For correct wrapping */
122 if (x
- '0' <= '9' - '0') {
124 } else if (x
- 'a' <= 'f' - 'a') {
126 } else if (x
- 'A' <= 'F' - 'A') {
135 if (x
- '0' <= '9' - '0')
136 return h
| (x
- '0');
137 if (x
- 'a' <= 'f' - 'a')
138 return h
| (x
- 'a' + 10);
139 if (x
- 'A' <= 'F' - 'A')
140 return h
| (x
- 'A' + 10);
145 * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary
146 * @src: Memory block holding binary GUID (16 bytes)
147 * @dest: Memory block to hold byte swapped binary GUID (16 bytes)
149 * Byte swap a binary GUID to match it's real GUID value
151 static void wmi_swap_bytes(u8
*src
, u8
*dest
)
155 for (i
= 0; i
<= 3; i
++)
156 memcpy(dest
+ i
, src
+ (3 - i
), 1);
158 for (i
= 0; i
<= 1; i
++)
159 memcpy(dest
+ 4 + i
, src
+ (5 - i
), 1);
161 for (i
= 0; i
<= 1; i
++)
162 memcpy(dest
+ 6 + i
, src
+ (7 - i
), 1);
164 memcpy(dest
+ 8, src
+ 8, 8);
168 * wmi_parse_guid - Convert GUID from ASCII to binary
169 * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
170 * @dest: Memory block to hold binary GUID (16 bytes)
172 * N.B. The GUID need not be NULL terminated.
174 * Return: 'true' @dest contains binary GUID
175 * 'false' @dest contents are undefined
177 static bool wmi_parse_guid(const u8
*src
, u8
*dest
)
179 static const int size
[] = { 4, 2, 2, 2, 6 };
182 if (src
[8] != '-' || src
[13] != '-' ||
183 src
[18] != '-' || src
[23] != '-')
186 for (j
= 0; j
< 5; j
++, src
++) {
187 for (i
= 0; i
< size
[j
]; i
++, src
+= 2, *dest
++ = v
) {
188 v
= wmi_parse_hexbyte(src
);
197 static bool find_guid(const char *guid_string
, struct wmi_block
**out
)
199 char tmp
[16], guid_input
[16];
200 struct wmi_block
*wblock
;
201 struct guid_block
*block
;
204 wmi_parse_guid(guid_string
, tmp
);
205 wmi_swap_bytes(tmp
, guid_input
);
207 list_for_each(p
, &wmi_blocks
.list
) {
208 wblock
= list_entry(p
, struct wmi_block
, list
);
209 block
= &wblock
->gblock
;
211 if (memcmp(block
->guid
, guid_input
, 16) == 0) {
221 * Exported WMI functions
224 * wmi_evaluate_method - Evaluate a WMI method
225 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
226 * @instance: Instance index
227 * @method_id: Method ID to call
228 * &in: Buffer containing input for the method call
229 * &out: Empty buffer to return the method results
231 * Call an ACPI-WMI method
233 acpi_status
wmi_evaluate_method(const char *guid_string
, u8 instance
,
234 u32 method_id
, const struct acpi_buffer
*in
, struct acpi_buffer
*out
)
236 struct guid_block
*block
= NULL
;
237 struct wmi_block
*wblock
= NULL
;
240 struct acpi_object_list input
;
241 union acpi_object params
[3];
242 char method
[4] = "WM";
244 if (!find_guid(guid_string
, &wblock
))
245 return AE_BAD_ADDRESS
;
247 block
= &wblock
->gblock
;
248 handle
= wblock
->handle
;
250 if (!(block
->flags
& ACPI_WMI_METHOD
))
253 if (block
->instance_count
< instance
)
254 return AE_BAD_PARAMETER
;
257 input
.pointer
= params
;
258 params
[0].type
= ACPI_TYPE_INTEGER
;
259 params
[0].integer
.value
= instance
;
260 params
[1].type
= ACPI_TYPE_INTEGER
;
261 params
[1].integer
.value
= method_id
;
266 if (block
->flags
& ACPI_WMI_STRING
) {
267 params
[2].type
= ACPI_TYPE_STRING
;
269 params
[2].type
= ACPI_TYPE_BUFFER
;
271 params
[2].buffer
.length
= in
->length
;
272 params
[2].buffer
.pointer
= in
->pointer
;
275 strncat(method
, block
->object_id
, 2);
277 status
= acpi_evaluate_object(handle
, method
, &input
, out
);
281 EXPORT_SYMBOL_GPL(wmi_evaluate_method
);
284 * wmi_query_block - Return contents of a WMI block
285 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
286 * @instance: Instance index
287 * &out: Empty buffer to return the contents of the data block to
289 * Return the contents of an ACPI-WMI data block to a buffer
291 acpi_status
wmi_query_block(const char *guid_string
, u8 instance
,
292 struct acpi_buffer
*out
)
294 struct guid_block
*block
= NULL
;
295 struct wmi_block
*wblock
= NULL
;
296 acpi_handle handle
, wc_handle
;
297 acpi_status status
, wc_status
= AE_ERROR
;
298 struct acpi_object_list input
, wc_input
;
299 union acpi_object wc_params
[1], wq_params
[1];
301 char wc_method
[4] = "WC";
303 if (!guid_string
|| !out
)
304 return AE_BAD_PARAMETER
;
306 if (!find_guid(guid_string
, &wblock
))
307 return AE_BAD_ADDRESS
;
309 block
= &wblock
->gblock
;
310 handle
= wblock
->handle
;
312 if (block
->instance_count
< instance
)
313 return AE_BAD_PARAMETER
;
315 /* Check GUID is a data block */
316 if (block
->flags
& (ACPI_WMI_EVENT
| ACPI_WMI_METHOD
))
317 return AE_BAD_ADDRESS
;
320 input
.pointer
= wq_params
;
321 wq_params
[0].type
= ACPI_TYPE_INTEGER
;
322 wq_params
[0].integer
.value
= instance
;
325 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
328 if (block
->flags
& ACPI_WMI_EXPENSIVE
) {
330 wc_input
.pointer
= wc_params
;
331 wc_params
[0].type
= ACPI_TYPE_INTEGER
;
332 wc_params
[0].integer
.value
= 1;
334 strncat(wc_method
, block
->object_id
, 2);
337 * Some GUIDs break the specification by declaring themselves
338 * expensive, but have no corresponding WCxx method. So we
339 * should not fail if this happens.
341 wc_status
= acpi_get_handle(handle
, wc_method
, &wc_handle
);
342 if (ACPI_SUCCESS(wc_status
))
343 wc_status
= acpi_evaluate_object(handle
, wc_method
,
347 strcpy(method
, "WQ");
348 strncat(method
, block
->object_id
, 2);
350 status
= acpi_evaluate_object(handle
, method
, &input
, out
);
353 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
354 * the WQxx method failed - we should disable collection anyway.
356 if ((block
->flags
& ACPI_WMI_EXPENSIVE
) && ACPI_SUCCESS(wc_status
)) {
357 wc_params
[0].integer
.value
= 0;
358 status
= acpi_evaluate_object(handle
,
359 wc_method
, &wc_input
, NULL
);
364 EXPORT_SYMBOL_GPL(wmi_query_block
);
367 * wmi_set_block - Write to a WMI block
368 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
369 * @instance: Instance index
370 * &in: Buffer containing new values for the data block
372 * Write the contents of the input buffer to an ACPI-WMI data block
374 acpi_status
wmi_set_block(const char *guid_string
, u8 instance
,
375 const struct acpi_buffer
*in
)
377 struct guid_block
*block
= NULL
;
378 struct wmi_block
*wblock
= NULL
;
380 struct acpi_object_list input
;
381 union acpi_object params
[2];
382 char method
[4] = "WS";
384 if (!guid_string
|| !in
)
387 if (!find_guid(guid_string
, &wblock
))
388 return AE_BAD_ADDRESS
;
390 block
= &wblock
->gblock
;
391 handle
= wblock
->handle
;
393 if (block
->instance_count
< instance
)
394 return AE_BAD_PARAMETER
;
396 /* Check GUID is a data block */
397 if (block
->flags
& (ACPI_WMI_EVENT
| ACPI_WMI_METHOD
))
398 return AE_BAD_ADDRESS
;
401 input
.pointer
= params
;
402 params
[0].type
= ACPI_TYPE_INTEGER
;
403 params
[0].integer
.value
= instance
;
405 if (block
->flags
& ACPI_WMI_STRING
) {
406 params
[1].type
= ACPI_TYPE_STRING
;
408 params
[1].type
= ACPI_TYPE_BUFFER
;
410 params
[1].buffer
.length
= in
->length
;
411 params
[1].buffer
.pointer
= in
->pointer
;
413 strncat(method
, block
->object_id
, 2);
415 return acpi_evaluate_object(handle
, method
, &input
, NULL
);
417 EXPORT_SYMBOL_GPL(wmi_set_block
);
420 * wmi_install_notify_handler - Register handler for WMI events
421 * @handler: Function to handle notifications
422 * @data: Data to be returned to handler when event is fired
424 * Register a handler for events sent to the ACPI-WMI mapper device.
426 acpi_status
wmi_install_notify_handler(const char *guid
,
427 wmi_notify_handler handler
, void *data
)
429 struct wmi_block
*block
;
431 if (!guid
|| !handler
)
432 return AE_BAD_PARAMETER
;
434 find_guid(guid
, &block
);
439 return AE_ALREADY_ACQUIRED
;
441 block
->handler
= handler
;
442 block
->handler_data
= data
;
446 EXPORT_SYMBOL_GPL(wmi_install_notify_handler
);
449 * wmi_uninstall_notify_handler - Unregister handler for WMI events
451 * Unregister handler for events sent to the ACPI-WMI mapper device.
453 acpi_status
wmi_remove_notify_handler(const char *guid
)
455 struct wmi_block
*block
;
458 return AE_BAD_PARAMETER
;
460 find_guid(guid
, &block
);
465 return AE_NULL_ENTRY
;
467 block
->handler
= NULL
;
468 block
->handler_data
= NULL
;
472 EXPORT_SYMBOL_GPL(wmi_remove_notify_handler
);
475 * wmi_get_event_data - Get WMI data associated with an event
477 * @event - Event to find
478 * &out - Buffer to hold event data
480 * Returns extra data associated with an event in WMI.
482 acpi_status
wmi_get_event_data(u32 event
, struct acpi_buffer
*out
)
484 struct acpi_object_list input
;
485 union acpi_object params
[1];
486 struct guid_block
*gblock
;
487 struct wmi_block
*wblock
;
491 input
.pointer
= params
;
492 params
[0].type
= ACPI_TYPE_INTEGER
;
493 params
[0].integer
.value
= event
;
495 list_for_each(p
, &wmi_blocks
.list
) {
496 wblock
= list_entry(p
, struct wmi_block
, list
);
497 gblock
= &wblock
->gblock
;
499 if ((gblock
->flags
& ACPI_WMI_EVENT
) &&
500 (gblock
->notify_id
== event
))
501 return acpi_evaluate_object(wblock
->handle
, "_WED",
507 EXPORT_SYMBOL_GPL(wmi_get_event_data
);
510 * wmi_has_guid - Check if a GUID is available
511 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
513 * Check if a given GUID is defined by _WDG
515 bool wmi_has_guid(const char *guid_string
)
517 return find_guid(guid_string
, NULL
);
519 EXPORT_SYMBOL_GPL(wmi_has_guid
);
522 * Parse the _WDG method for the GUID data blocks
524 static __init acpi_status
parse_wdg(acpi_handle handle
)
526 struct acpi_buffer out
= {ACPI_ALLOCATE_BUFFER
, NULL
};
527 union acpi_object
*obj
;
528 struct guid_block
*gblock
;
529 struct wmi_block
*wblock
;
533 status
= acpi_evaluate_object(handle
, "_WDG", NULL
, &out
);
535 if (ACPI_FAILURE(status
))
538 obj
= (union acpi_object
*) out
.pointer
;
540 if (obj
->type
!= ACPI_TYPE_BUFFER
)
543 total
= obj
->buffer
.length
/ sizeof(struct guid_block
);
545 gblock
= kzalloc(obj
->buffer
.length
, GFP_KERNEL
);
549 memcpy(gblock
, obj
->buffer
.pointer
, obj
->buffer
.length
);
551 for (i
= 0; i
< total
; i
++) {
552 wblock
= kzalloc(sizeof(struct wmi_block
), GFP_KERNEL
);
556 wblock
->gblock
= gblock
[i
];
557 wblock
->handle
= handle
;
558 list_add_tail(&wblock
->list
, &wmi_blocks
.list
);
568 * WMI can have EmbeddedControl access regions. In which case, we just want to
569 * hand these off to the EC driver.
572 acpi_wmi_ec_space_handler(u32 function
, acpi_physical_address address
,
573 u32 bits
, acpi_integer
* value
,
574 void *handler_context
, void *region_context
)
576 int result
= 0, i
= 0;
579 if ((address
> 0xFF) || !value
)
580 return AE_BAD_PARAMETER
;
582 if (function
!= ACPI_READ
&& function
!= ACPI_WRITE
)
583 return AE_BAD_PARAMETER
;
586 return AE_BAD_PARAMETER
;
588 if (function
== ACPI_READ
) {
589 result
= ec_read(address
, &temp
);
590 (*value
) |= ((acpi_integer
)temp
) << i
;
592 temp
= 0xff & ((*value
) >> i
);
593 result
= ec_write(address
, temp
);
598 return AE_BAD_PARAMETER
;
611 static void acpi_wmi_notify(acpi_handle handle
, u32 event
, void *data
)
613 struct guid_block
*block
;
614 struct wmi_block
*wblock
;
616 struct acpi_device
*device
= data
;
618 list_for_each(p
, &wmi_blocks
.list
) {
619 wblock
= list_entry(p
, struct wmi_block
, list
);
620 block
= &wblock
->gblock
;
622 if ((block
->flags
& ACPI_WMI_EVENT
) &&
623 (block
->notify_id
== event
)) {
625 wblock
->handler(event
, wblock
->handler_data
);
627 acpi_bus_generate_netlink_event(
628 device
->pnp
.device_class
, device
->dev
.bus_id
,
635 static int acpi_wmi_remove(struct acpi_device
*device
, int type
)
637 acpi_remove_notify_handler(device
->handle
, ACPI_DEVICE_NOTIFY
,
640 acpi_remove_address_space_handler(device
->handle
,
641 ACPI_ADR_SPACE_EC
, &acpi_wmi_ec_space_handler
);
646 static int __init
acpi_wmi_add(struct acpi_device
*device
)
651 status
= acpi_install_notify_handler(device
->handle
, ACPI_DEVICE_NOTIFY
,
652 acpi_wmi_notify
, device
);
653 if (ACPI_FAILURE(status
)) {
654 printk(KERN_ERR PREFIX
"Error installing notify handler\n");
658 status
= acpi_install_address_space_handler(device
->handle
,
660 &acpi_wmi_ec_space_handler
,
662 if (ACPI_FAILURE(status
))
665 status
= parse_wdg(device
->handle
);
666 if (ACPI_FAILURE(status
)) {
667 printk(KERN_ERR PREFIX
"Error installing EC region handler\n");
674 static int __init
acpi_wmi_init(void)
678 INIT_LIST_HEAD(&wmi_blocks
.list
);
683 result
= acpi_bus_register_driver(&acpi_wmi_driver
);
686 printk(KERN_INFO PREFIX
"Error loading mapper\n");
688 printk(KERN_INFO PREFIX
"Mapper loaded\n");
694 static void __exit
acpi_wmi_exit(void)
696 struct list_head
*p
, *tmp
;
697 struct wmi_block
*wblock
;
699 acpi_bus_unregister_driver(&acpi_wmi_driver
);
701 list_for_each_safe(p
, tmp
, &wmi_blocks
.list
) {
702 wblock
= list_entry(p
, struct wmi_block
, list
);
708 printk(KERN_INFO PREFIX
"Mapper unloaded\n");
711 subsys_initcall(acpi_wmi_init
);
712 module_exit(acpi_wmi_exit
);