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 * WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
12 * Copyright (C) 2015 Andrew Lutomirski
13 * Copyright (C) 2017 VMware, Inc. All Rights Reserved.
15 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or (at
20 * your option) any later version.
22 * This program is distributed in the hope that it will be useful, but
23 * WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25 * General Public License for more details.
27 * You should have received a copy of the GNU General Public License along
28 * with this program; if not, write to the Free Software Foundation, Inc.,
29 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
31 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
34 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
36 #include <linux/kernel.h>
37 #include <linux/init.h>
38 #include <linux/types.h>
39 #include <linux/device.h>
40 #include <linux/list.h>
41 #include <linux/acpi.h>
42 #include <linux/slab.h>
43 #include <linux/module.h>
44 #include <linux/platform_device.h>
45 #include <linux/wmi.h>
46 #include <linux/uuid.h>
48 ACPI_MODULE_NAME("wmi");
49 MODULE_AUTHOR("Carlos Corbacho");
50 MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
51 MODULE_LICENSE("GPL");
53 static LIST_HEAD(wmi_block_list);
60 unsigned char notify_id;
61 unsigned char reserved;
69 struct wmi_device dev;
70 struct list_head list;
71 struct guid_block gblock;
72 struct acpi_device *acpi_device;
73 wmi_notify_handler handler;
76 bool read_takes_no_args;
81 * If the GUID data block is marked as expensive, we must enable and
82 * explicitily disable data collection.
84 #define ACPI_WMI_EXPENSIVE 0x1
85 #define ACPI_WMI_METHOD 0x2 /* GUID is a method */
86 #define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */
87 #define ACPI_WMI_EVENT 0x8 /* GUID is an event */
89 static bool debug_event;
90 module_param(debug_event, bool, 0444);
91 MODULE_PARM_DESC(debug_event,
92 "Log WMI Events [0/1]");
94 static bool debug_dump_wdg;
95 module_param(debug_dump_wdg, bool, 0444);
96 MODULE_PARM_DESC(debug_dump_wdg,
97 "Dump available WMI interfaces [0/1]");
99 static int acpi_wmi_remove(struct platform_device *device);
100 static int acpi_wmi_probe(struct platform_device *device);
102 static const struct acpi_device_id wmi_device_ids[] = {
107 MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
109 static struct platform_driver acpi_wmi_driver = {
112 .acpi_match_table = wmi_device_ids,
114 .probe = acpi_wmi_probe,
115 .remove = acpi_wmi_remove,
119 * GUID parsing functions
122 static bool find_guid(const char *guid_string, struct wmi_block **out)
125 struct wmi_block *wblock;
126 struct guid_block *block;
129 if (uuid_le_to_bin(guid_string, &guid_input))
132 list_for_each(p, &wmi_block_list) {
133 wblock = list_entry(p, struct wmi_block, list);
134 block = &wblock->gblock;
136 if (memcmp(block->guid, &guid_input, 16) == 0) {
145 static int get_subobj_info(acpi_handle handle, const char *pathname,
146 struct acpi_device_info **info)
148 struct acpi_device_info *dummy_info, **info_ptr;
149 acpi_handle subobj_handle;
152 status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
153 if (status == AE_NOT_FOUND)
155 else if (ACPI_FAILURE(status))
158 info_ptr = info ? info : &dummy_info;
159 status = acpi_get_object_info(subobj_handle, info_ptr);
160 if (ACPI_FAILURE(status))
169 static acpi_status wmi_method_enable(struct wmi_block *wblock, int enable)
171 struct guid_block *block = NULL;
176 block = &wblock->gblock;
177 handle = wblock->acpi_device->handle;
179 snprintf(method, 5, "WE%02X", block->notify_id);
180 status = acpi_execute_simple_method(handle, method, enable);
182 if (status != AE_OK && status != AE_NOT_FOUND)
189 * Exported WMI functions
192 * wmi_evaluate_method - Evaluate a WMI method
193 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
194 * @instance: Instance index
195 * @method_id: Method ID to call
196 * &in: Buffer containing input for the method call
197 * &out: Empty buffer to return the method results
199 * Call an ACPI-WMI method
201 acpi_status wmi_evaluate_method(const char *guid_string, u8 instance,
202 u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out)
204 struct guid_block *block = NULL;
205 struct wmi_block *wblock = NULL;
208 struct acpi_object_list input;
209 union acpi_object params[3];
210 char method[5] = "WM";
212 if (!find_guid(guid_string, &wblock))
215 block = &wblock->gblock;
216 handle = wblock->acpi_device->handle;
218 if (!(block->flags & ACPI_WMI_METHOD))
221 if (block->instance_count <= instance)
222 return AE_BAD_PARAMETER;
225 input.pointer = params;
226 params[0].type = ACPI_TYPE_INTEGER;
227 params[0].integer.value = instance;
228 params[1].type = ACPI_TYPE_INTEGER;
229 params[1].integer.value = method_id;
234 if (block->flags & ACPI_WMI_STRING) {
235 params[2].type = ACPI_TYPE_STRING;
237 params[2].type = ACPI_TYPE_BUFFER;
239 params[2].buffer.length = in->length;
240 params[2].buffer.pointer = in->pointer;
243 strncat(method, block->object_id, 2);
245 status = acpi_evaluate_object(handle, method, &input, out);
249 EXPORT_SYMBOL_GPL(wmi_evaluate_method);
251 static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
252 struct acpi_buffer *out)
254 struct guid_block *block = NULL;
256 acpi_status status, wc_status = AE_ERROR;
257 struct acpi_object_list input;
258 union acpi_object wq_params[1];
260 char wc_method[5] = "WC";
263 return AE_BAD_PARAMETER;
265 block = &wblock->gblock;
266 handle = wblock->acpi_device->handle;
268 if (block->instance_count <= instance)
269 return AE_BAD_PARAMETER;
271 /* Check GUID is a data block */
272 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
276 input.pointer = wq_params;
277 wq_params[0].type = ACPI_TYPE_INTEGER;
278 wq_params[0].integer.value = instance;
280 if (instance == 0 && wblock->read_takes_no_args)
284 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
287 if (block->flags & ACPI_WMI_EXPENSIVE) {
288 strncat(wc_method, block->object_id, 2);
291 * Some GUIDs break the specification by declaring themselves
292 * expensive, but have no corresponding WCxx method. So we
293 * should not fail if this happens.
295 if (acpi_has_method(handle, wc_method))
296 wc_status = acpi_execute_simple_method(handle,
300 strcpy(method, "WQ");
301 strncat(method, block->object_id, 2);
303 status = acpi_evaluate_object(handle, method, &input, out);
306 * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
307 * the WQxx method failed - we should disable collection anyway.
309 if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
311 * Ignore whether this WCxx call succeeds or not since
312 * the previously executed WQxx method call might have
313 * succeeded, and returning the failing status code
314 * of this call would throw away the result of the WQxx
315 * call, potentially leaking memory.
317 acpi_execute_simple_method(handle, wc_method, 0);
324 * wmi_query_block - Return contents of a WMI block (deprecated)
325 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
326 * @instance: Instance index
327 * &out: Empty buffer to return the contents of the data block to
329 * Return the contents of an ACPI-WMI data block to a buffer
331 acpi_status wmi_query_block(const char *guid_string, u8 instance,
332 struct acpi_buffer *out)
334 struct wmi_block *wblock;
337 return AE_BAD_PARAMETER;
339 if (!find_guid(guid_string, &wblock))
342 return __query_block(wblock, instance, out);
344 EXPORT_SYMBOL_GPL(wmi_query_block);
346 union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
348 struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
349 struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
351 if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
354 return (union acpi_object *)out.pointer;
356 EXPORT_SYMBOL_GPL(wmidev_block_query);
358 struct wmi_device *wmidev_get_other_guid(struct wmi_device *wdev,
359 const char *guid_string)
361 struct wmi_block *this_wb = container_of(wdev, struct wmi_block, dev);
362 struct wmi_block *other_wb;
364 if (!find_guid(guid_string, &other_wb))
367 if (other_wb->acpi_device != this_wb->acpi_device)
370 get_device(&other_wb->dev.dev);
371 return &other_wb->dev;
373 EXPORT_SYMBOL_GPL(wmidev_get_other_guid);
376 * wmi_set_block - Write to a WMI block
377 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
378 * @instance: Instance index
379 * &in: Buffer containing new values for the data block
381 * Write the contents of the input buffer to an ACPI-WMI data block
383 acpi_status wmi_set_block(const char *guid_string, u8 instance,
384 const struct acpi_buffer *in)
386 struct guid_block *block = NULL;
387 struct wmi_block *wblock = NULL;
389 struct acpi_object_list input;
390 union acpi_object params[2];
391 char method[5] = "WS";
393 if (!guid_string || !in)
396 if (!find_guid(guid_string, &wblock))
399 block = &wblock->gblock;
400 handle = wblock->acpi_device->handle;
402 if (block->instance_count <= instance)
403 return AE_BAD_PARAMETER;
405 /* Check GUID is a data block */
406 if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
410 input.pointer = params;
411 params[0].type = ACPI_TYPE_INTEGER;
412 params[0].integer.value = instance;
414 if (block->flags & ACPI_WMI_STRING) {
415 params[1].type = ACPI_TYPE_STRING;
417 params[1].type = ACPI_TYPE_BUFFER;
419 params[1].buffer.length = in->length;
420 params[1].buffer.pointer = in->pointer;
422 strncat(method, block->object_id, 2);
424 return acpi_evaluate_object(handle, method, &input, NULL);
426 EXPORT_SYMBOL_GPL(wmi_set_block);
428 static void wmi_dump_wdg(const struct guid_block *g)
430 pr_info("%pUL:\n", g->guid);
431 if (g->flags & ACPI_WMI_EVENT)
432 pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
434 pr_info("\tobject_id: %2pE\n", g->object_id);
435 pr_info("\tinstance_count: %d\n", g->instance_count);
436 pr_info("\tflags: %#x", g->flags);
438 if (g->flags & ACPI_WMI_EXPENSIVE)
439 pr_cont(" ACPI_WMI_EXPENSIVE");
440 if (g->flags & ACPI_WMI_METHOD)
441 pr_cont(" ACPI_WMI_METHOD");
442 if (g->flags & ACPI_WMI_STRING)
443 pr_cont(" ACPI_WMI_STRING");
444 if (g->flags & ACPI_WMI_EVENT)
445 pr_cont(" ACPI_WMI_EVENT");
451 static void wmi_notify_debug(u32 value, void *context)
453 struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
454 union acpi_object *obj;
457 status = wmi_get_event_data(value, &response);
458 if (status != AE_OK) {
459 pr_info("bad event status 0x%x\n", status);
463 obj = (union acpi_object *)response.pointer;
468 pr_info("DEBUG Event ");
470 case ACPI_TYPE_BUFFER:
471 pr_cont("BUFFER_TYPE - length %d\n", obj->buffer.length);
473 case ACPI_TYPE_STRING:
474 pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
476 case ACPI_TYPE_INTEGER:
477 pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
479 case ACPI_TYPE_PACKAGE:
480 pr_cont("PACKAGE_TYPE - %d elements\n", obj->package.count);
483 pr_cont("object type 0x%X\n", obj->type);
489 * wmi_install_notify_handler - Register handler for WMI events
490 * @handler: Function to handle notifications
491 * @data: Data to be returned to handler when event is fired
493 * Register a handler for events sent to the ACPI-WMI mapper device.
495 acpi_status wmi_install_notify_handler(const char *guid,
496 wmi_notify_handler handler, void *data)
498 struct wmi_block *block;
499 acpi_status status = AE_NOT_EXIST;
503 if (!guid || !handler)
504 return AE_BAD_PARAMETER;
506 if (uuid_le_to_bin(guid, &guid_input))
507 return AE_BAD_PARAMETER;
509 list_for_each(p, &wmi_block_list) {
510 acpi_status wmi_status;
511 block = list_entry(p, struct wmi_block, list);
513 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
514 if (block->handler &&
515 block->handler != wmi_notify_debug)
516 return AE_ALREADY_ACQUIRED;
518 block->handler = handler;
519 block->handler_data = data;
521 wmi_status = wmi_method_enable(block, 1);
522 if ((wmi_status != AE_OK) ||
523 ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
530 EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
533 * wmi_uninstall_notify_handler - Unregister handler for WMI events
535 * Unregister handler for events sent to the ACPI-WMI mapper device.
537 acpi_status wmi_remove_notify_handler(const char *guid)
539 struct wmi_block *block;
540 acpi_status status = AE_NOT_EXIST;
545 return AE_BAD_PARAMETER;
547 if (uuid_le_to_bin(guid, &guid_input))
548 return AE_BAD_PARAMETER;
550 list_for_each(p, &wmi_block_list) {
551 acpi_status wmi_status;
552 block = list_entry(p, struct wmi_block, list);
554 if (memcmp(block->gblock.guid, &guid_input, 16) == 0) {
555 if (!block->handler ||
556 block->handler == wmi_notify_debug)
557 return AE_NULL_ENTRY;
560 block->handler = wmi_notify_debug;
563 wmi_status = wmi_method_enable(block, 0);
564 block->handler = NULL;
565 block->handler_data = NULL;
566 if ((wmi_status != AE_OK) ||
567 ((wmi_status == AE_OK) &&
568 (status == AE_NOT_EXIST)))
576 EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
579 * wmi_get_event_data - Get WMI data associated with an event
581 * @event: Event to find
582 * @out: Buffer to hold event data. out->pointer should be freed with kfree()
584 * Returns extra data associated with an event in WMI.
586 acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
588 struct acpi_object_list input;
589 union acpi_object params[1];
590 struct guid_block *gblock;
591 struct wmi_block *wblock;
595 input.pointer = params;
596 params[0].type = ACPI_TYPE_INTEGER;
597 params[0].integer.value = event;
599 list_for_each(p, &wmi_block_list) {
600 wblock = list_entry(p, struct wmi_block, list);
601 gblock = &wblock->gblock;
603 if ((gblock->flags & ACPI_WMI_EVENT) &&
604 (gblock->notify_id == event))
605 return acpi_evaluate_object(wblock->acpi_device->handle,
606 "_WED", &input, out);
611 EXPORT_SYMBOL_GPL(wmi_get_event_data);
614 * wmi_has_guid - Check if a GUID is available
615 * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
617 * Check if a given GUID is defined by _WDG
619 bool wmi_has_guid(const char *guid_string)
621 return find_guid(guid_string, NULL);
623 EXPORT_SYMBOL_GPL(wmi_has_guid);
625 static struct wmi_block *dev_to_wblock(struct device *dev)
627 return container_of(dev, struct wmi_block, dev.dev);
630 static struct wmi_device *dev_to_wdev(struct device *dev)
632 return container_of(dev, struct wmi_device, dev);
638 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
641 struct wmi_block *wblock = dev_to_wblock(dev);
643 return sprintf(buf, "wmi:%pUL\n", wblock->gblock.guid);
645 static DEVICE_ATTR_RO(modalias);
647 static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
650 struct wmi_block *wblock = dev_to_wblock(dev);
652 return sprintf(buf, "%pUL\n", wblock->gblock.guid);
654 static DEVICE_ATTR_RO(guid);
656 static ssize_t instance_count_show(struct device *dev,
657 struct device_attribute *attr, char *buf)
659 struct wmi_block *wblock = dev_to_wblock(dev);
661 return sprintf(buf, "%d\n", (int)wblock->gblock.instance_count);
663 static DEVICE_ATTR_RO(instance_count);
665 static ssize_t expensive_show(struct device *dev,
666 struct device_attribute *attr, char *buf)
668 struct wmi_block *wblock = dev_to_wblock(dev);
670 return sprintf(buf, "%d\n",
671 (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
673 static DEVICE_ATTR_RO(expensive);
675 static struct attribute *wmi_attrs[] = {
676 &dev_attr_modalias.attr,
678 &dev_attr_instance_count.attr,
679 &dev_attr_expensive.attr,
682 ATTRIBUTE_GROUPS(wmi);
684 static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
687 struct wmi_block *wblock = dev_to_wblock(dev);
689 return sprintf(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
691 static DEVICE_ATTR_RO(notify_id);
693 static struct attribute *wmi_event_attrs[] = {
694 &dev_attr_notify_id.attr,
697 ATTRIBUTE_GROUPS(wmi_event);
699 static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
702 struct wmi_block *wblock = dev_to_wblock(dev);
704 return sprintf(buf, "%c%c\n", wblock->gblock.object_id[0],
705 wblock->gblock.object_id[1]);
707 static DEVICE_ATTR_RO(object_id);
709 static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
712 struct wmi_device *wdev = dev_to_wdev(dev);
714 return sprintf(buf, "%d\n", (int)wdev->setable);
716 static DEVICE_ATTR_RO(setable);
718 static struct attribute *wmi_data_attrs[] = {
719 &dev_attr_object_id.attr,
720 &dev_attr_setable.attr,
723 ATTRIBUTE_GROUPS(wmi_data);
725 static struct attribute *wmi_method_attrs[] = {
726 &dev_attr_object_id.attr,
729 ATTRIBUTE_GROUPS(wmi_method);
731 static int wmi_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
733 struct wmi_block *wblock = dev_to_wblock(dev);
735 if (add_uevent_var(env, "MODALIAS=wmi:%pUL", wblock->gblock.guid))
738 if (add_uevent_var(env, "WMI_GUID=%pUL", wblock->gblock.guid))
744 static void wmi_dev_release(struct device *dev)
746 struct wmi_block *wblock = dev_to_wblock(dev);
751 static int wmi_dev_match(struct device *dev, struct device_driver *driver)
753 struct wmi_driver *wmi_driver =
754 container_of(driver, struct wmi_driver, driver);
755 struct wmi_block *wblock = dev_to_wblock(dev);
756 const struct wmi_device_id *id = wmi_driver->id_table;
761 while (id->guid_string) {
764 if (WARN_ON(uuid_le_to_bin(id->guid_string, &driver_guid)))
766 if (!memcmp(&driver_guid, wblock->gblock.guid, 16))
775 static int wmi_dev_probe(struct device *dev)
777 struct wmi_block *wblock = dev_to_wblock(dev);
778 struct wmi_driver *wdriver =
779 container_of(dev->driver, struct wmi_driver, driver);
782 if (ACPI_FAILURE(wmi_method_enable(wblock, 1)))
783 dev_warn(dev, "failed to enable device -- probing anyway\n");
785 if (wdriver->probe) {
786 ret = wdriver->probe(dev_to_wdev(dev));
787 if (ret != 0 && ACPI_FAILURE(wmi_method_enable(wblock, 0)))
788 dev_warn(dev, "failed to disable device\n");
794 static int wmi_dev_remove(struct device *dev)
796 struct wmi_block *wblock = dev_to_wblock(dev);
797 struct wmi_driver *wdriver =
798 container_of(dev->driver, struct wmi_driver, driver);
802 ret = wdriver->remove(dev_to_wdev(dev));
804 if (ACPI_FAILURE(wmi_method_enable(wblock, 0)))
805 dev_warn(dev, "failed to disable device\n");
810 static struct class wmi_bus_class = {
814 static struct bus_type wmi_bus_type = {
816 .dev_groups = wmi_groups,
817 .match = wmi_dev_match,
818 .uevent = wmi_dev_uevent,
819 .probe = wmi_dev_probe,
820 .remove = wmi_dev_remove,
823 static struct device_type wmi_type_event = {
825 .groups = wmi_event_groups,
826 .release = wmi_dev_release,
829 static struct device_type wmi_type_method = {
831 .groups = wmi_method_groups,
832 .release = wmi_dev_release,
835 static struct device_type wmi_type_data = {
837 .groups = wmi_data_groups,
838 .release = wmi_dev_release,
841 static int wmi_create_device(struct device *wmi_bus_dev,
842 const struct guid_block *gblock,
843 struct wmi_block *wblock,
844 struct acpi_device *device)
846 struct acpi_device_info *info;
850 if (gblock->flags & ACPI_WMI_EVENT) {
851 wblock->dev.dev.type = &wmi_type_event;
855 if (gblock->flags & ACPI_WMI_METHOD) {
856 wblock->dev.dev.type = &wmi_type_method;
861 * Data Block Query Control Method (WQxx by convention) is
862 * required per the WMI documentation. If it is not present,
863 * we ignore this data block.
865 strcpy(method, "WQ");
866 strncat(method, wblock->gblock.object_id, 2);
867 result = get_subobj_info(device->handle, method, &info);
870 dev_warn(wmi_bus_dev,
871 "%s data block query control method not found",
876 wblock->dev.dev.type = &wmi_type_data;
879 * The Microsoft documentation specifically states:
881 * Data blocks registered with only a single instance
882 * can ignore the parameter.
884 * ACPICA will get mad at us if we call the method with the wrong number
885 * of arguments, so check what our method expects. (On some Dell
886 * laptops, WQxx may not be a method at all.)
888 if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
889 wblock->read_takes_no_args = true;
893 strcpy(method, "WS");
894 strncat(method, wblock->gblock.object_id, 2);
895 result = get_subobj_info(device->handle, method, NULL);
898 wblock->dev.setable = true;
901 wblock->dev.dev.bus = &wmi_bus_type;
902 wblock->dev.dev.parent = wmi_bus_dev;
904 dev_set_name(&wblock->dev.dev, "%pUL", gblock->guid);
906 device_initialize(&wblock->dev.dev);
911 static void wmi_free_devices(struct acpi_device *device)
913 struct wmi_block *wblock, *next;
915 /* Delete devices for all the GUIDs */
916 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
917 if (wblock->acpi_device == device) {
918 list_del(&wblock->list);
919 device_unregister(&wblock->dev.dev);
924 static bool guid_already_parsed(struct acpi_device *device,
927 struct wmi_block *wblock;
929 list_for_each_entry(wblock, &wmi_block_list, list) {
930 if (memcmp(wblock->gblock.guid, guid, 16) == 0) {
932 * Because we historically didn't track the relationship
933 * between GUIDs and ACPI nodes, we don't know whether
934 * we need to suppress GUIDs that are unique on a
935 * given node but duplicated across nodes.
937 dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
938 guid, dev_name(&wblock->acpi_device->dev));
947 * Parse the _WDG method for the GUID data blocks
949 static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
951 struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
952 const struct guid_block *gblock;
953 struct wmi_block *wblock, *next;
954 union acpi_object *obj;
959 status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
960 if (ACPI_FAILURE(status))
963 obj = (union acpi_object *) out.pointer;
967 if (obj->type != ACPI_TYPE_BUFFER) {
972 gblock = (const struct guid_block *)obj->buffer.pointer;
973 total = obj->buffer.length / sizeof(struct guid_block);
975 for (i = 0; i < total; i++) {
977 wmi_dump_wdg(&gblock[i]);
980 * Some WMI devices, like those for nVidia hooks, have a
981 * duplicate GUID. It's not clear what we should do in this
982 * case yet, so for now, we'll just ignore the duplicate
983 * for device creation.
985 if (guid_already_parsed(device, gblock[i].guid))
988 wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
990 dev_err(wmi_bus_dev, "Failed to allocate %pUL\n", &gblock[i].guid);
994 wblock->acpi_device = device;
995 wblock->gblock = gblock[i];
997 retval = wmi_create_device(wmi_bus_dev, &gblock[i], wblock, device);
1003 list_add_tail(&wblock->list, &wmi_block_list);
1006 wblock->handler = wmi_notify_debug;
1007 wmi_method_enable(wblock, 1);
1012 * Now that all of the devices are created, add them to the
1013 * device tree and probe subdrivers.
1015 list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
1016 if (wblock->acpi_device != device)
1019 retval = device_add(&wblock->dev.dev);
1021 dev_err(wmi_bus_dev, "failed to register %pULL\n",
1022 wblock->gblock.guid);
1024 wmi_method_enable(wblock, 0);
1025 list_del(&wblock->list);
1026 put_device(&wblock->dev.dev);
1036 * WMI can have EmbeddedControl access regions. In which case, we just want to
1037 * hand these off to the EC driver.
1040 acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
1041 u32 bits, u64 *value,
1042 void *handler_context, void *region_context)
1044 int result = 0, i = 0;
1047 if ((address > 0xFF) || !value)
1048 return AE_BAD_PARAMETER;
1050 if (function != ACPI_READ && function != ACPI_WRITE)
1051 return AE_BAD_PARAMETER;
1054 return AE_BAD_PARAMETER;
1056 if (function == ACPI_READ) {
1057 result = ec_read(address, &temp);
1058 (*value) |= ((u64)temp) << i;
1060 temp = 0xff & ((*value) >> i);
1061 result = ec_write(address, temp);
1066 return AE_BAD_PARAMETER;
1069 return AE_NOT_FOUND;
1079 static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
1082 struct guid_block *block;
1083 struct wmi_block *wblock;
1084 struct list_head *p;
1085 bool found_it = false;
1087 list_for_each(p, &wmi_block_list) {
1088 wblock = list_entry(p, struct wmi_block, list);
1089 block = &wblock->gblock;
1091 if (wblock->acpi_device->handle == handle &&
1092 (block->flags & ACPI_WMI_EVENT) &&
1093 (block->notify_id == event))
1103 /* If a driver is bound, then notify the driver. */
1104 if (wblock->dev.dev.driver) {
1105 struct wmi_driver *driver;
1106 struct acpi_object_list input;
1107 union acpi_object params[1];
1108 struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
1111 driver = container_of(wblock->dev.dev.driver,
1112 struct wmi_driver, driver);
1115 input.pointer = params;
1116 params[0].type = ACPI_TYPE_INTEGER;
1117 params[0].integer.value = event;
1119 status = acpi_evaluate_object(wblock->acpi_device->handle,
1120 "_WED", &input, &evdata);
1121 if (ACPI_FAILURE(status)) {
1122 dev_warn(&wblock->dev.dev,
1123 "failed to get event data\n");
1128 driver->notify(&wblock->dev,
1129 (union acpi_object *)evdata.pointer);
1131 kfree(evdata.pointer);
1132 } else if (wblock->handler) {
1133 /* Legacy handler */
1134 wblock->handler(event, wblock->handler_data);
1138 pr_info("DEBUG Event GUID: %pUL\n",
1139 wblock->gblock.guid);
1142 acpi_bus_generate_netlink_event(
1143 wblock->acpi_device->pnp.device_class,
1144 dev_name(&wblock->dev.dev),
1149 static int acpi_wmi_remove(struct platform_device *device)
1151 struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
1153 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1154 acpi_wmi_notify_handler);
1155 acpi_remove_address_space_handler(acpi_device->handle,
1156 ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
1157 wmi_free_devices(acpi_device);
1158 device_unregister((struct device *)dev_get_drvdata(&device->dev));
1163 static int acpi_wmi_probe(struct platform_device *device)
1165 struct acpi_device *acpi_device;
1166 struct device *wmi_bus_dev;
1170 acpi_device = ACPI_COMPANION(&device->dev);
1172 dev_err(&device->dev, "ACPI companion is missing\n");
1176 status = acpi_install_address_space_handler(acpi_device->handle,
1178 &acpi_wmi_ec_space_handler,
1180 if (ACPI_FAILURE(status)) {
1181 dev_err(&device->dev, "Error installing EC region handler\n");
1185 status = acpi_install_notify_handler(acpi_device->handle,
1187 acpi_wmi_notify_handler,
1189 if (ACPI_FAILURE(status)) {
1190 dev_err(&device->dev, "Error installing notify handler\n");
1192 goto err_remove_ec_handler;
1195 wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
1196 NULL, "wmi_bus-%s", dev_name(&device->dev));
1197 if (IS_ERR(wmi_bus_dev)) {
1198 error = PTR_ERR(wmi_bus_dev);
1199 goto err_remove_notify_handler;
1201 dev_set_drvdata(&device->dev, wmi_bus_dev);
1203 error = parse_wdg(wmi_bus_dev, acpi_device);
1205 pr_err("Failed to parse WDG method\n");
1206 goto err_remove_busdev;
1212 device_unregister(wmi_bus_dev);
1214 err_remove_notify_handler:
1215 acpi_remove_notify_handler(acpi_device->handle, ACPI_DEVICE_NOTIFY,
1216 acpi_wmi_notify_handler);
1218 err_remove_ec_handler:
1219 acpi_remove_address_space_handler(acpi_device->handle,
1221 &acpi_wmi_ec_space_handler);
1226 int __must_check __wmi_driver_register(struct wmi_driver *driver,
1227 struct module *owner)
1229 driver->driver.owner = owner;
1230 driver->driver.bus = &wmi_bus_type;
1232 return driver_register(&driver->driver);
1234 EXPORT_SYMBOL(__wmi_driver_register);
1236 void wmi_driver_unregister(struct wmi_driver *driver)
1238 driver_unregister(&driver->driver);
1240 EXPORT_SYMBOL(wmi_driver_unregister);
1242 static int __init acpi_wmi_init(void)
1249 error = class_register(&wmi_bus_class);
1253 error = bus_register(&wmi_bus_type);
1255 goto err_unreg_class;
1257 error = platform_driver_register(&acpi_wmi_driver);
1259 pr_err("Error loading mapper\n");
1266 bus_unregister(&wmi_bus_type);
1269 class_unregister(&wmi_bus_class);
1274 static void __exit acpi_wmi_exit(void)
1276 platform_driver_unregister(&acpi_wmi_driver);
1277 class_unregister(&wmi_bus_class);
1278 bus_unregister(&wmi_bus_type);
1281 subsys_initcall_sync(acpi_wmi_init);
1282 module_exit(acpi_wmi_exit);