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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/platform/x86/wmi.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/platform/x86/wmi.c')
-rw-r--r--drivers/platform/x86/wmi.c1581
1 files changed, 1581 insertions, 0 deletions
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
new file mode 100644
index 0000000000..d75a0ae9cd
--- /dev/null
+++ b/drivers/platform/x86/wmi.c
@@ -0,0 +1,1581 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ACPI-WMI mapping driver
+ *
+ * Copyright (C) 2007-2008 Carlos Corbacho <carlos@strangeworlds.co.uk>
+ *
+ * GUID parsing code from ldm.c is:
+ * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
+ * Copyright (c) 2001-2007 Anton Altaparmakov
+ * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
+ *
+ * WMI bus infrastructure by Andrew Lutomirski and Darren Hart:
+ * Copyright (C) 2015 Andrew Lutomirski
+ * Copyright (C) 2017 VMware, Inc. All Rights Reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/acpi.h>
+#include <linux/bits.h>
+#include <linux/build_bug.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+#include <linux/uuid.h>
+#include <linux/wmi.h>
+#include <linux/fs.h>
+#include <uapi/linux/wmi.h>
+
+MODULE_AUTHOR("Carlos Corbacho");
+MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
+MODULE_LICENSE("GPL");
+
+static LIST_HEAD(wmi_block_list);
+
+struct guid_block {
+ guid_t guid;
+ union {
+ char object_id[2];
+ struct {
+ unsigned char notify_id;
+ unsigned char reserved;
+ };
+ };
+ u8 instance_count;
+ u8 flags;
+} __packed;
+static_assert(sizeof(typeof_member(struct guid_block, guid)) == 16);
+static_assert(sizeof(struct guid_block) == 20);
+static_assert(__alignof__(struct guid_block) == 1);
+
+enum { /* wmi_block flags */
+ WMI_READ_TAKES_NO_ARGS,
+ WMI_PROBED,
+};
+
+struct wmi_block {
+ struct wmi_device dev;
+ struct list_head list;
+ struct guid_block gblock;
+ struct miscdevice char_dev;
+ struct mutex char_mutex;
+ struct acpi_device *acpi_device;
+ wmi_notify_handler handler;
+ void *handler_data;
+ u64 req_buf_size;
+ unsigned long flags;
+};
+
+
+/*
+ * If the GUID data block is marked as expensive, we must enable and
+ * explicitily disable data collection.
+ */
+#define ACPI_WMI_EXPENSIVE BIT(0)
+#define ACPI_WMI_METHOD BIT(1) /* GUID is a method */
+#define ACPI_WMI_STRING BIT(2) /* GUID takes & returns a string */
+#define ACPI_WMI_EVENT BIT(3) /* GUID is an event */
+
+static bool debug_event;
+module_param(debug_event, bool, 0444);
+MODULE_PARM_DESC(debug_event,
+ "Log WMI Events [0/1]");
+
+static bool debug_dump_wdg;
+module_param(debug_dump_wdg, bool, 0444);
+MODULE_PARM_DESC(debug_dump_wdg,
+ "Dump available WMI interfaces [0/1]");
+
+static const struct acpi_device_id wmi_device_ids[] = {
+ {"PNP0C14", 0},
+ {"pnp0c14", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
+
+/* allow duplicate GUIDs as these device drivers use struct wmi_driver */
+static const char * const allow_duplicates[] = {
+ "05901221-D566-11D1-B2F0-00A0C9062910", /* wmi-bmof */
+ "8A42EA14-4F2A-FD45-6422-0087F7A7E608", /* dell-wmi-ddv */
+ NULL
+};
+
+/*
+ * GUID parsing functions
+ */
+
+static acpi_status find_guid(const char *guid_string, struct wmi_block **out)
+{
+ guid_t guid_input;
+ struct wmi_block *wblock;
+
+ if (!guid_string)
+ return AE_BAD_PARAMETER;
+
+ if (guid_parse(guid_string, &guid_input))
+ return AE_BAD_PARAMETER;
+
+ list_for_each_entry(wblock, &wmi_block_list, list) {
+ if (guid_equal(&wblock->gblock.guid, &guid_input)) {
+ if (out)
+ *out = wblock;
+
+ return AE_OK;
+ }
+ }
+
+ return AE_NOT_FOUND;
+}
+
+static bool guid_parse_and_compare(const char *string, const guid_t *guid)
+{
+ guid_t guid_input;
+
+ if (guid_parse(string, &guid_input))
+ return false;
+
+ return guid_equal(&guid_input, guid);
+}
+
+static const void *find_guid_context(struct wmi_block *wblock,
+ struct wmi_driver *wdriver)
+{
+ const struct wmi_device_id *id;
+
+ id = wdriver->id_table;
+ if (!id)
+ return NULL;
+
+ while (*id->guid_string) {
+ if (guid_parse_and_compare(id->guid_string, &wblock->gblock.guid))
+ return id->context;
+ id++;
+ }
+ return NULL;
+}
+
+static int get_subobj_info(acpi_handle handle, const char *pathname,
+ struct acpi_device_info **info)
+{
+ struct acpi_device_info *dummy_info, **info_ptr;
+ acpi_handle subobj_handle;
+ acpi_status status;
+
+ status = acpi_get_handle(handle, (char *)pathname, &subobj_handle);
+ if (status == AE_NOT_FOUND)
+ return -ENOENT;
+ else if (ACPI_FAILURE(status))
+ return -EIO;
+
+ info_ptr = info ? info : &dummy_info;
+ status = acpi_get_object_info(subobj_handle, info_ptr);
+ if (ACPI_FAILURE(status))
+ return -EIO;
+
+ if (!info)
+ kfree(dummy_info);
+
+ return 0;
+}
+
+static acpi_status wmi_method_enable(struct wmi_block *wblock, bool enable)
+{
+ struct guid_block *block;
+ char method[5];
+ acpi_status status;
+ acpi_handle handle;
+
+ block = &wblock->gblock;
+ handle = wblock->acpi_device->handle;
+
+ snprintf(method, 5, "WE%02X", block->notify_id);
+ status = acpi_execute_simple_method(handle, method, enable);
+ if (status == AE_NOT_FOUND)
+ return AE_OK;
+
+ return status;
+}
+
+#define WMI_ACPI_METHOD_NAME_SIZE 5
+
+static inline void get_acpi_method_name(const struct wmi_block *wblock,
+ const char method,
+ char buffer[static WMI_ACPI_METHOD_NAME_SIZE])
+{
+ static_assert(ARRAY_SIZE(wblock->gblock.object_id) == 2);
+ static_assert(WMI_ACPI_METHOD_NAME_SIZE >= 5);
+
+ buffer[0] = 'W';
+ buffer[1] = method;
+ buffer[2] = wblock->gblock.object_id[0];
+ buffer[3] = wblock->gblock.object_id[1];
+ buffer[4] = '\0';
+}
+
+static inline acpi_object_type get_param_acpi_type(const struct wmi_block *wblock)
+{
+ if (wblock->gblock.flags & ACPI_WMI_STRING)
+ return ACPI_TYPE_STRING;
+ else
+ return ACPI_TYPE_BUFFER;
+}
+
+static acpi_status get_event_data(const struct wmi_block *wblock, struct acpi_buffer *out)
+{
+ union acpi_object param = {
+ .integer = {
+ .type = ACPI_TYPE_INTEGER,
+ .value = wblock->gblock.notify_id,
+ }
+ };
+ struct acpi_object_list input = {
+ .count = 1,
+ .pointer = &param,
+ };
+
+ return acpi_evaluate_object(wblock->acpi_device->handle, "_WED", &input, out);
+}
+
+/*
+ * Exported WMI functions
+ */
+
+/**
+ * set_required_buffer_size - Sets the buffer size needed for performing IOCTL
+ * @wdev: A wmi bus device from a driver
+ * @length: Required buffer size
+ *
+ * Allocates memory needed for buffer, stores the buffer size in that memory.
+ *
+ * Return: 0 on success or a negative error code for failure.
+ */
+int set_required_buffer_size(struct wmi_device *wdev, u64 length)
+{
+ struct wmi_block *wblock;
+
+ wblock = container_of(wdev, struct wmi_block, dev);
+ wblock->req_buf_size = length;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(set_required_buffer_size);
+
+/**
+ * wmi_instance_count - Get number of WMI object instances
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ *
+ * Get the number of WMI object instances.
+ *
+ * Returns: Number of WMI object instances or negative error code.
+ */
+int wmi_instance_count(const char *guid_string)
+{
+ struct wmi_block *wblock;
+ acpi_status status;
+
+ status = find_guid(guid_string, &wblock);
+ if (ACPI_FAILURE(status)) {
+ if (status == AE_BAD_PARAMETER)
+ return -EINVAL;
+
+ return -ENODEV;
+ }
+
+ return wmidev_instance_count(&wblock->dev);
+}
+EXPORT_SYMBOL_GPL(wmi_instance_count);
+
+/**
+ * wmidev_instance_count - Get number of WMI object instances
+ * @wdev: A wmi bus device from a driver
+ *
+ * Get the number of WMI object instances.
+ *
+ * Returns: Number of WMI object instances.
+ */
+u8 wmidev_instance_count(struct wmi_device *wdev)
+{
+ struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
+
+ return wblock->gblock.instance_count;
+}
+EXPORT_SYMBOL_GPL(wmidev_instance_count);
+
+/**
+ * wmi_evaluate_method - Evaluate a WMI method (deprecated)
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @instance: Instance index
+ * @method_id: Method ID to call
+ * @in: Buffer containing input for the method call
+ * @out: Empty buffer to return the method results
+ *
+ * Call an ACPI-WMI method, the caller must free @out.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmi_evaluate_method(const char *guid_string, u8 instance, u32 method_id,
+ const struct acpi_buffer *in, struct acpi_buffer *out)
+{
+ struct wmi_block *wblock = NULL;
+ acpi_status status;
+
+ status = find_guid(guid_string, &wblock);
+ if (ACPI_FAILURE(status))
+ return status;
+
+ return wmidev_evaluate_method(&wblock->dev, instance, method_id,
+ in, out);
+}
+EXPORT_SYMBOL_GPL(wmi_evaluate_method);
+
+/**
+ * wmidev_evaluate_method - Evaluate a WMI method
+ * @wdev: A wmi bus device from a driver
+ * @instance: Instance index
+ * @method_id: Method ID to call
+ * @in: Buffer containing input for the method call
+ * @out: Empty buffer to return the method results
+ *
+ * Call an ACPI-WMI method, the caller must free @out.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmidev_evaluate_method(struct wmi_device *wdev, u8 instance, u32 method_id,
+ const struct acpi_buffer *in, struct acpi_buffer *out)
+{
+ struct guid_block *block;
+ struct wmi_block *wblock;
+ acpi_handle handle;
+ struct acpi_object_list input;
+ union acpi_object params[3];
+ char method[WMI_ACPI_METHOD_NAME_SIZE];
+
+ wblock = container_of(wdev, struct wmi_block, dev);
+ block = &wblock->gblock;
+ handle = wblock->acpi_device->handle;
+
+ if (!(block->flags & ACPI_WMI_METHOD))
+ return AE_BAD_DATA;
+
+ if (block->instance_count <= instance)
+ return AE_BAD_PARAMETER;
+
+ input.count = 2;
+ input.pointer = params;
+ params[0].type = ACPI_TYPE_INTEGER;
+ params[0].integer.value = instance;
+ params[1].type = ACPI_TYPE_INTEGER;
+ params[1].integer.value = method_id;
+
+ if (in) {
+ input.count = 3;
+
+ params[2].type = get_param_acpi_type(wblock);
+ params[2].buffer.length = in->length;
+ params[2].buffer.pointer = in->pointer;
+ }
+
+ get_acpi_method_name(wblock, 'M', method);
+
+ return acpi_evaluate_object(handle, method, &input, out);
+}
+EXPORT_SYMBOL_GPL(wmidev_evaluate_method);
+
+static acpi_status __query_block(struct wmi_block *wblock, u8 instance,
+ struct acpi_buffer *out)
+{
+ struct guid_block *block;
+ acpi_handle handle;
+ acpi_status status, wc_status = AE_ERROR;
+ struct acpi_object_list input;
+ union acpi_object wq_params[1];
+ char wc_method[WMI_ACPI_METHOD_NAME_SIZE];
+ char method[WMI_ACPI_METHOD_NAME_SIZE];
+
+ if (!out)
+ return AE_BAD_PARAMETER;
+
+ block = &wblock->gblock;
+ handle = wblock->acpi_device->handle;
+
+ if (block->instance_count <= instance)
+ return AE_BAD_PARAMETER;
+
+ /* Check GUID is a data block */
+ if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
+ return AE_ERROR;
+
+ input.count = 1;
+ input.pointer = wq_params;
+ wq_params[0].type = ACPI_TYPE_INTEGER;
+ wq_params[0].integer.value = instance;
+
+ if (instance == 0 && test_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags))
+ input.count = 0;
+
+ /*
+ * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to
+ * enable collection.
+ */
+ if (block->flags & ACPI_WMI_EXPENSIVE) {
+ get_acpi_method_name(wblock, 'C', wc_method);
+
+ /*
+ * Some GUIDs break the specification by declaring themselves
+ * expensive, but have no corresponding WCxx method. So we
+ * should not fail if this happens.
+ */
+ wc_status = acpi_execute_simple_method(handle, wc_method, 1);
+ }
+
+ get_acpi_method_name(wblock, 'Q', method);
+ status = acpi_evaluate_object(handle, method, &input, out);
+
+ /*
+ * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method, even if
+ * the WQxx method failed - we should disable collection anyway.
+ */
+ if ((block->flags & ACPI_WMI_EXPENSIVE) && ACPI_SUCCESS(wc_status)) {
+ /*
+ * Ignore whether this WCxx call succeeds or not since
+ * the previously executed WQxx method call might have
+ * succeeded, and returning the failing status code
+ * of this call would throw away the result of the WQxx
+ * call, potentially leaking memory.
+ */
+ acpi_execute_simple_method(handle, wc_method, 0);
+ }
+
+ return status;
+}
+
+/**
+ * wmi_query_block - Return contents of a WMI block (deprecated)
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @instance: Instance index
+ * @out: Empty buffer to return the contents of the data block to
+ *
+ * Query a ACPI-WMI block, the caller must free @out.
+ *
+ * Return: ACPI object containing the content of the WMI block.
+ */
+acpi_status wmi_query_block(const char *guid_string, u8 instance,
+ struct acpi_buffer *out)
+{
+ struct wmi_block *wblock;
+ acpi_status status;
+
+ status = find_guid(guid_string, &wblock);
+ if (ACPI_FAILURE(status))
+ return status;
+
+ return __query_block(wblock, instance, out);
+}
+EXPORT_SYMBOL_GPL(wmi_query_block);
+
+/**
+ * wmidev_block_query - Return contents of a WMI block
+ * @wdev: A wmi bus device from a driver
+ * @instance: Instance index
+ *
+ * Query an ACPI-WMI block, the caller must free the result.
+ *
+ * Return: ACPI object containing the content of the WMI block.
+ */
+union acpi_object *wmidev_block_query(struct wmi_device *wdev, u8 instance)
+{
+ struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
+
+ if (ACPI_FAILURE(__query_block(wblock, instance, &out)))
+ return NULL;
+
+ return out.pointer;
+}
+EXPORT_SYMBOL_GPL(wmidev_block_query);
+
+/**
+ * wmi_set_block - Write to a WMI block (deprecated)
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @instance: Instance index
+ * @in: Buffer containing new values for the data block
+ *
+ * Write the contents of the input buffer to an ACPI-WMI data block.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmi_set_block(const char *guid_string, u8 instance,
+ const struct acpi_buffer *in)
+{
+ struct wmi_block *wblock = NULL;
+ struct guid_block *block;
+ acpi_handle handle;
+ struct acpi_object_list input;
+ union acpi_object params[2];
+ char method[WMI_ACPI_METHOD_NAME_SIZE];
+ acpi_status status;
+
+ if (!in)
+ return AE_BAD_DATA;
+
+ status = find_guid(guid_string, &wblock);
+ if (ACPI_FAILURE(status))
+ return status;
+
+ block = &wblock->gblock;
+ handle = wblock->acpi_device->handle;
+
+ if (block->instance_count <= instance)
+ return AE_BAD_PARAMETER;
+
+ /* Check GUID is a data block */
+ if (block->flags & (ACPI_WMI_EVENT | ACPI_WMI_METHOD))
+ return AE_ERROR;
+
+ input.count = 2;
+ input.pointer = params;
+ params[0].type = ACPI_TYPE_INTEGER;
+ params[0].integer.value = instance;
+ params[1].type = get_param_acpi_type(wblock);
+ params[1].buffer.length = in->length;
+ params[1].buffer.pointer = in->pointer;
+
+ get_acpi_method_name(wblock, 'S', method);
+
+ return acpi_evaluate_object(handle, method, &input, NULL);
+}
+EXPORT_SYMBOL_GPL(wmi_set_block);
+
+static void wmi_dump_wdg(const struct guid_block *g)
+{
+ pr_info("%pUL:\n", &g->guid);
+ if (g->flags & ACPI_WMI_EVENT)
+ pr_info("\tnotify_id: 0x%02X\n", g->notify_id);
+ else
+ pr_info("\tobject_id: %2pE\n", g->object_id);
+ pr_info("\tinstance_count: %d\n", g->instance_count);
+ pr_info("\tflags: %#x", g->flags);
+ if (g->flags) {
+ if (g->flags & ACPI_WMI_EXPENSIVE)
+ pr_cont(" ACPI_WMI_EXPENSIVE");
+ if (g->flags & ACPI_WMI_METHOD)
+ pr_cont(" ACPI_WMI_METHOD");
+ if (g->flags & ACPI_WMI_STRING)
+ pr_cont(" ACPI_WMI_STRING");
+ if (g->flags & ACPI_WMI_EVENT)
+ pr_cont(" ACPI_WMI_EVENT");
+ }
+ pr_cont("\n");
+
+}
+
+static void wmi_notify_debug(u32 value, void *context)
+{
+ struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *obj;
+ acpi_status status;
+
+ status = wmi_get_event_data(value, &response);
+ if (status != AE_OK) {
+ pr_info("bad event status 0x%x\n", status);
+ return;
+ }
+
+ obj = response.pointer;
+ if (!obj)
+ return;
+
+ pr_info("DEBUG: event 0x%02X ", value);
+ switch (obj->type) {
+ case ACPI_TYPE_BUFFER:
+ pr_cont("BUFFER_TYPE - length %u\n", obj->buffer.length);
+ break;
+ case ACPI_TYPE_STRING:
+ pr_cont("STRING_TYPE - %s\n", obj->string.pointer);
+ break;
+ case ACPI_TYPE_INTEGER:
+ pr_cont("INTEGER_TYPE - %llu\n", obj->integer.value);
+ break;
+ case ACPI_TYPE_PACKAGE:
+ pr_cont("PACKAGE_TYPE - %u elements\n", obj->package.count);
+ break;
+ default:
+ pr_cont("object type 0x%X\n", obj->type);
+ }
+ kfree(obj);
+}
+
+/**
+ * wmi_install_notify_handler - Register handler for WMI events (deprecated)
+ * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @handler: Function to handle notifications
+ * @data: Data to be returned to handler when event is fired
+ *
+ * Register a handler for events sent to the ACPI-WMI mapper device.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmi_install_notify_handler(const char *guid,
+ wmi_notify_handler handler,
+ void *data)
+{
+ struct wmi_block *block;
+ acpi_status status = AE_NOT_EXIST;
+ guid_t guid_input;
+
+ if (!guid || !handler)
+ return AE_BAD_PARAMETER;
+
+ if (guid_parse(guid, &guid_input))
+ return AE_BAD_PARAMETER;
+
+ list_for_each_entry(block, &wmi_block_list, list) {
+ acpi_status wmi_status;
+
+ if (guid_equal(&block->gblock.guid, &guid_input)) {
+ if (block->handler &&
+ block->handler != wmi_notify_debug)
+ return AE_ALREADY_ACQUIRED;
+
+ block->handler = handler;
+ block->handler_data = data;
+
+ wmi_status = wmi_method_enable(block, true);
+ if ((wmi_status != AE_OK) ||
+ ((wmi_status == AE_OK) && (status == AE_NOT_EXIST)))
+ status = wmi_status;
+ }
+ }
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(wmi_install_notify_handler);
+
+/**
+ * wmi_remove_notify_handler - Unregister handler for WMI events (deprecated)
+ * @guid: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ *
+ * Unregister handler for events sent to the ACPI-WMI mapper device.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmi_remove_notify_handler(const char *guid)
+{
+ struct wmi_block *block;
+ acpi_status status = AE_NOT_EXIST;
+ guid_t guid_input;
+
+ if (!guid)
+ return AE_BAD_PARAMETER;
+
+ if (guid_parse(guid, &guid_input))
+ return AE_BAD_PARAMETER;
+
+ list_for_each_entry(block, &wmi_block_list, list) {
+ acpi_status wmi_status;
+
+ if (guid_equal(&block->gblock.guid, &guid_input)) {
+ if (!block->handler ||
+ block->handler == wmi_notify_debug)
+ return AE_NULL_ENTRY;
+
+ if (debug_event) {
+ block->handler = wmi_notify_debug;
+ status = AE_OK;
+ } else {
+ wmi_status = wmi_method_enable(block, false);
+ block->handler = NULL;
+ block->handler_data = NULL;
+ if ((wmi_status != AE_OK) ||
+ ((wmi_status == AE_OK) &&
+ (status == AE_NOT_EXIST)))
+ status = wmi_status;
+ }
+ }
+ }
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
+
+/**
+ * wmi_get_event_data - Get WMI data associated with an event (deprecated)
+ *
+ * @event: Event to find
+ * @out: Buffer to hold event data
+ *
+ * Get extra data associated with an WMI event, the caller needs to free @out.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out)
+{
+ struct wmi_block *wblock;
+
+ list_for_each_entry(wblock, &wmi_block_list, list) {
+ struct guid_block *gblock = &wblock->gblock;
+
+ if ((gblock->flags & ACPI_WMI_EVENT) && gblock->notify_id == event)
+ return get_event_data(wblock, out);
+ }
+
+ return AE_NOT_FOUND;
+}
+EXPORT_SYMBOL_GPL(wmi_get_event_data);
+
+/**
+ * wmi_has_guid - Check if a GUID is available
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ *
+ * Check if a given GUID is defined by _WDG.
+ *
+ * Return: True if GUID is available, false otherwise.
+ */
+bool wmi_has_guid(const char *guid_string)
+{
+ return ACPI_SUCCESS(find_guid(guid_string, NULL));
+}
+EXPORT_SYMBOL_GPL(wmi_has_guid);
+
+/**
+ * wmi_get_acpi_device_uid() - Get _UID name of ACPI device that defines GUID (deprecated)
+ * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ *
+ * Find the _UID of ACPI device associated with this WMI GUID.
+ *
+ * Return: The ACPI _UID field value or NULL if the WMI GUID was not found.
+ */
+char *wmi_get_acpi_device_uid(const char *guid_string)
+{
+ struct wmi_block *wblock = NULL;
+ acpi_status status;
+
+ status = find_guid(guid_string, &wblock);
+ if (ACPI_FAILURE(status))
+ return NULL;
+
+ return acpi_device_uid(wblock->acpi_device);
+}
+EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
+
+#define dev_to_wblock(__dev) container_of_const(__dev, struct wmi_block, dev.dev)
+#define dev_to_wdev(__dev) container_of_const(__dev, struct wmi_device, dev)
+
+static inline struct wmi_driver *drv_to_wdrv(struct device_driver *drv)
+{
+ return container_of(drv, struct wmi_driver, driver);
+}
+
+/*
+ * sysfs interface
+ */
+static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ return sysfs_emit(buf, "wmi:%pUL\n", &wblock->gblock.guid);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ return sysfs_emit(buf, "%pUL\n", &wblock->gblock.guid);
+}
+static DEVICE_ATTR_RO(guid);
+
+static ssize_t instance_count_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ return sysfs_emit(buf, "%d\n", (int)wblock->gblock.instance_count);
+}
+static DEVICE_ATTR_RO(instance_count);
+
+static ssize_t expensive_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ return sysfs_emit(buf, "%d\n",
+ (wblock->gblock.flags & ACPI_WMI_EXPENSIVE) != 0);
+}
+static DEVICE_ATTR_RO(expensive);
+
+static struct attribute *wmi_attrs[] = {
+ &dev_attr_modalias.attr,
+ &dev_attr_guid.attr,
+ &dev_attr_instance_count.attr,
+ &dev_attr_expensive.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(wmi);
+
+static ssize_t notify_id_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ return sysfs_emit(buf, "%02X\n", (unsigned int)wblock->gblock.notify_id);
+}
+static DEVICE_ATTR_RO(notify_id);
+
+static struct attribute *wmi_event_attrs[] = {
+ &dev_attr_notify_id.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(wmi_event);
+
+static ssize_t object_id_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ return sysfs_emit(buf, "%c%c\n", wblock->gblock.object_id[0],
+ wblock->gblock.object_id[1]);
+}
+static DEVICE_ATTR_RO(object_id);
+
+static ssize_t setable_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct wmi_device *wdev = dev_to_wdev(dev);
+
+ return sysfs_emit(buf, "%d\n", (int)wdev->setable);
+}
+static DEVICE_ATTR_RO(setable);
+
+static struct attribute *wmi_data_attrs[] = {
+ &dev_attr_object_id.attr,
+ &dev_attr_setable.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(wmi_data);
+
+static struct attribute *wmi_method_attrs[] = {
+ &dev_attr_object_id.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(wmi_method);
+
+static int wmi_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)
+{
+ const struct wmi_block *wblock = dev_to_wblock(dev);
+
+ if (add_uevent_var(env, "MODALIAS=wmi:%pUL", &wblock->gblock.guid))
+ return -ENOMEM;
+
+ if (add_uevent_var(env, "WMI_GUID=%pUL", &wblock->gblock.guid))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void wmi_dev_release(struct device *dev)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ kfree(wblock);
+}
+
+static int wmi_dev_match(struct device *dev, struct device_driver *driver)
+{
+ struct wmi_driver *wmi_driver = drv_to_wdrv(driver);
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ const struct wmi_device_id *id = wmi_driver->id_table;
+
+ if (id == NULL)
+ return 0;
+
+ while (*id->guid_string) {
+ if (guid_parse_and_compare(id->guid_string, &wblock->gblock.guid))
+ return 1;
+
+ id++;
+ }
+
+ return 0;
+}
+static int wmi_char_open(struct inode *inode, struct file *filp)
+{
+ /*
+ * The miscdevice already stores a pointer to itself
+ * inside filp->private_data
+ */
+ struct wmi_block *wblock = container_of(filp->private_data, struct wmi_block, char_dev);
+
+ filp->private_data = wblock;
+
+ return nonseekable_open(inode, filp);
+}
+
+static ssize_t wmi_char_read(struct file *filp, char __user *buffer,
+ size_t length, loff_t *offset)
+{
+ struct wmi_block *wblock = filp->private_data;
+
+ return simple_read_from_buffer(buffer, length, offset,
+ &wblock->req_buf_size,
+ sizeof(wblock->req_buf_size));
+}
+
+static long wmi_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ struct wmi_ioctl_buffer __user *input =
+ (struct wmi_ioctl_buffer __user *) arg;
+ struct wmi_block *wblock = filp->private_data;
+ struct wmi_ioctl_buffer *buf;
+ struct wmi_driver *wdriver;
+ int ret;
+
+ if (_IOC_TYPE(cmd) != WMI_IOC)
+ return -ENOTTY;
+
+ /* make sure we're not calling a higher instance than exists*/
+ if (_IOC_NR(cmd) >= wblock->gblock.instance_count)
+ return -EINVAL;
+
+ mutex_lock(&wblock->char_mutex);
+ buf = wblock->handler_data;
+ if (get_user(buf->length, &input->length)) {
+ dev_dbg(&wblock->dev.dev, "Read length from user failed\n");
+ ret = -EFAULT;
+ goto out_ioctl;
+ }
+ /* if it's too small, abort */
+ if (buf->length < wblock->req_buf_size) {
+ dev_err(&wblock->dev.dev,
+ "Buffer %lld too small, need at least %lld\n",
+ buf->length, wblock->req_buf_size);
+ ret = -EINVAL;
+ goto out_ioctl;
+ }
+ /* if it's too big, warn, driver will only use what is needed */
+ if (buf->length > wblock->req_buf_size)
+ dev_warn(&wblock->dev.dev,
+ "Buffer %lld is bigger than required %lld\n",
+ buf->length, wblock->req_buf_size);
+
+ /* copy the structure from userspace */
+ if (copy_from_user(buf, input, wblock->req_buf_size)) {
+ dev_dbg(&wblock->dev.dev, "Copy %llu from user failed\n",
+ wblock->req_buf_size);
+ ret = -EFAULT;
+ goto out_ioctl;
+ }
+
+ /* let the driver do any filtering and do the call */
+ wdriver = drv_to_wdrv(wblock->dev.dev.driver);
+ if (!try_module_get(wdriver->driver.owner)) {
+ ret = -EBUSY;
+ goto out_ioctl;
+ }
+ ret = wdriver->filter_callback(&wblock->dev, cmd, buf);
+ module_put(wdriver->driver.owner);
+ if (ret)
+ goto out_ioctl;
+
+ /* return the result (only up to our internal buffer size) */
+ if (copy_to_user(input, buf, wblock->req_buf_size)) {
+ dev_dbg(&wblock->dev.dev, "Copy %llu to user failed\n",
+ wblock->req_buf_size);
+ ret = -EFAULT;
+ }
+
+out_ioctl:
+ mutex_unlock(&wblock->char_mutex);
+ return ret;
+}
+
+static const struct file_operations wmi_fops = {
+ .owner = THIS_MODULE,
+ .read = wmi_char_read,
+ .open = wmi_char_open,
+ .unlocked_ioctl = wmi_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+};
+
+static int wmi_dev_probe(struct device *dev)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ struct wmi_driver *wdriver = drv_to_wdrv(dev->driver);
+ int ret = 0;
+ char *buf;
+
+ if (ACPI_FAILURE(wmi_method_enable(wblock, true)))
+ dev_warn(dev, "failed to enable device -- probing anyway\n");
+
+ if (wdriver->probe) {
+ ret = wdriver->probe(dev_to_wdev(dev),
+ find_guid_context(wblock, wdriver));
+ if (ret != 0)
+ goto probe_failure;
+ }
+
+ /* driver wants a character device made */
+ if (wdriver->filter_callback) {
+ /* check that required buffer size declared by driver or MOF */
+ if (!wblock->req_buf_size) {
+ dev_err(&wblock->dev.dev,
+ "Required buffer size not set\n");
+ ret = -EINVAL;
+ goto probe_failure;
+ }
+
+ wblock->handler_data = kmalloc(wblock->req_buf_size,
+ GFP_KERNEL);
+ if (!wblock->handler_data) {
+ ret = -ENOMEM;
+ goto probe_failure;
+ }
+
+ buf = kasprintf(GFP_KERNEL, "wmi/%s", wdriver->driver.name);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto probe_string_failure;
+ }
+ wblock->char_dev.minor = MISC_DYNAMIC_MINOR;
+ wblock->char_dev.name = buf;
+ wblock->char_dev.fops = &wmi_fops;
+ wblock->char_dev.mode = 0444;
+ ret = misc_register(&wblock->char_dev);
+ if (ret) {
+ dev_warn(dev, "failed to register char dev: %d\n", ret);
+ ret = -ENOMEM;
+ goto probe_misc_failure;
+ }
+ }
+
+ set_bit(WMI_PROBED, &wblock->flags);
+ return 0;
+
+probe_misc_failure:
+ kfree(buf);
+probe_string_failure:
+ kfree(wblock->handler_data);
+probe_failure:
+ if (ACPI_FAILURE(wmi_method_enable(wblock, false)))
+ dev_warn(dev, "failed to disable device\n");
+ return ret;
+}
+
+static void wmi_dev_remove(struct device *dev)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ struct wmi_driver *wdriver = drv_to_wdrv(dev->driver);
+
+ clear_bit(WMI_PROBED, &wblock->flags);
+
+ if (wdriver->filter_callback) {
+ misc_deregister(&wblock->char_dev);
+ kfree(wblock->char_dev.name);
+ kfree(wblock->handler_data);
+ }
+
+ if (wdriver->remove)
+ wdriver->remove(dev_to_wdev(dev));
+
+ if (ACPI_FAILURE(wmi_method_enable(wblock, false)))
+ dev_warn(dev, "failed to disable device\n");
+}
+
+static struct class wmi_bus_class = {
+ .name = "wmi_bus",
+};
+
+static struct bus_type wmi_bus_type = {
+ .name = "wmi",
+ .dev_groups = wmi_groups,
+ .match = wmi_dev_match,
+ .uevent = wmi_dev_uevent,
+ .probe = wmi_dev_probe,
+ .remove = wmi_dev_remove,
+};
+
+static const struct device_type wmi_type_event = {
+ .name = "event",
+ .groups = wmi_event_groups,
+ .release = wmi_dev_release,
+};
+
+static const struct device_type wmi_type_method = {
+ .name = "method",
+ .groups = wmi_method_groups,
+ .release = wmi_dev_release,
+};
+
+static const struct device_type wmi_type_data = {
+ .name = "data",
+ .groups = wmi_data_groups,
+ .release = wmi_dev_release,
+};
+
+/*
+ * _WDG is a static list that is only parsed at startup,
+ * so it's safe to count entries without extra protection.
+ */
+static int guid_count(const guid_t *guid)
+{
+ struct wmi_block *wblock;
+ int count = 0;
+
+ list_for_each_entry(wblock, &wmi_block_list, list) {
+ if (guid_equal(&wblock->gblock.guid, guid))
+ count++;
+ }
+
+ return count;
+}
+
+static int wmi_create_device(struct device *wmi_bus_dev,
+ struct wmi_block *wblock,
+ struct acpi_device *device)
+{
+ struct acpi_device_info *info;
+ char method[WMI_ACPI_METHOD_NAME_SIZE];
+ int result;
+ uint count;
+
+ if (wblock->gblock.flags & ACPI_WMI_EVENT) {
+ wblock->dev.dev.type = &wmi_type_event;
+ goto out_init;
+ }
+
+ if (wblock->gblock.flags & ACPI_WMI_METHOD) {
+ wblock->dev.dev.type = &wmi_type_method;
+ mutex_init(&wblock->char_mutex);
+ goto out_init;
+ }
+
+ /*
+ * Data Block Query Control Method (WQxx by convention) is
+ * required per the WMI documentation. If it is not present,
+ * we ignore this data block.
+ */
+ get_acpi_method_name(wblock, 'Q', method);
+ result = get_subobj_info(device->handle, method, &info);
+
+ if (result) {
+ dev_warn(wmi_bus_dev,
+ "%s data block query control method not found\n",
+ method);
+ return result;
+ }
+
+ wblock->dev.dev.type = &wmi_type_data;
+
+ /*
+ * The Microsoft documentation specifically states:
+ *
+ * Data blocks registered with only a single instance
+ * can ignore the parameter.
+ *
+ * ACPICA will get mad at us if we call the method with the wrong number
+ * of arguments, so check what our method expects. (On some Dell
+ * laptops, WQxx may not be a method at all.)
+ */
+ if (info->type != ACPI_TYPE_METHOD || info->param_count == 0)
+ set_bit(WMI_READ_TAKES_NO_ARGS, &wblock->flags);
+
+ kfree(info);
+
+ get_acpi_method_name(wblock, 'S', method);
+ result = get_subobj_info(device->handle, method, NULL);
+
+ if (result == 0)
+ wblock->dev.setable = true;
+
+ out_init:
+ wblock->dev.dev.bus = &wmi_bus_type;
+ wblock->dev.dev.parent = wmi_bus_dev;
+
+ count = guid_count(&wblock->gblock.guid);
+ if (count)
+ dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, count);
+ else
+ dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid);
+
+ device_initialize(&wblock->dev.dev);
+
+ return 0;
+}
+
+static void wmi_free_devices(struct acpi_device *device)
+{
+ struct wmi_block *wblock, *next;
+
+ /* Delete devices for all the GUIDs */
+ list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
+ if (wblock->acpi_device == device) {
+ list_del(&wblock->list);
+ device_unregister(&wblock->dev.dev);
+ }
+ }
+}
+
+static bool guid_already_parsed_for_legacy(struct acpi_device *device, const guid_t *guid)
+{
+ struct wmi_block *wblock;
+
+ list_for_each_entry(wblock, &wmi_block_list, list) {
+ /* skip warning and register if we know the driver will use struct wmi_driver */
+ for (int i = 0; allow_duplicates[i] != NULL; i++) {
+ if (guid_parse_and_compare(allow_duplicates[i], guid))
+ return false;
+ }
+ if (guid_equal(&wblock->gblock.guid, guid)) {
+ /*
+ * Because we historically didn't track the relationship
+ * between GUIDs and ACPI nodes, we don't know whether
+ * we need to suppress GUIDs that are unique on a
+ * given node but duplicated across nodes.
+ */
+ dev_warn(&device->dev, "duplicate WMI GUID %pUL (first instance was on %s)\n",
+ guid, dev_name(&wblock->acpi_device->dev));
+ return true;
+ }
+ }
+
+ return false;
+}
+
+/*
+ * Parse the _WDG method for the GUID data blocks
+ */
+static int parse_wdg(struct device *wmi_bus_dev, struct acpi_device *device)
+{
+ struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
+ const struct guid_block *gblock;
+ struct wmi_block *wblock, *next;
+ union acpi_object *obj;
+ acpi_status status;
+ u32 i, total;
+ int retval;
+
+ status = acpi_evaluate_object(device->handle, "_WDG", NULL, &out);
+ if (ACPI_FAILURE(status))
+ return -ENXIO;
+
+ obj = out.pointer;
+ if (!obj)
+ return -ENXIO;
+
+ if (obj->type != ACPI_TYPE_BUFFER) {
+ kfree(obj);
+ return -ENXIO;
+ }
+
+ gblock = (const struct guid_block *)obj->buffer.pointer;
+ total = obj->buffer.length / sizeof(struct guid_block);
+
+ for (i = 0; i < total; i++) {
+ if (debug_dump_wdg)
+ wmi_dump_wdg(&gblock[i]);
+
+ if (!gblock[i].instance_count) {
+ dev_info(wmi_bus_dev, FW_INFO "%pUL has zero instances\n", &gblock[i].guid);
+ continue;
+ }
+
+ if (guid_already_parsed_for_legacy(device, &gblock[i].guid))
+ continue;
+
+ wblock = kzalloc(sizeof(*wblock), GFP_KERNEL);
+ if (!wblock) {
+ dev_err(wmi_bus_dev, "Failed to allocate %pUL\n", &gblock[i].guid);
+ continue;
+ }
+
+ wblock->acpi_device = device;
+ wblock->gblock = gblock[i];
+
+ retval = wmi_create_device(wmi_bus_dev, wblock, device);
+ if (retval) {
+ kfree(wblock);
+ continue;
+ }
+
+ list_add_tail(&wblock->list, &wmi_block_list);
+
+ if (debug_event) {
+ wblock->handler = wmi_notify_debug;
+ wmi_method_enable(wblock, true);
+ }
+ }
+
+ /*
+ * Now that all of the devices are created, add them to the
+ * device tree and probe subdrivers.
+ */
+ list_for_each_entry_safe(wblock, next, &wmi_block_list, list) {
+ if (wblock->acpi_device != device)
+ continue;
+
+ retval = device_add(&wblock->dev.dev);
+ if (retval) {
+ dev_err(wmi_bus_dev, "failed to register %pUL\n",
+ &wblock->gblock.guid);
+ if (debug_event)
+ wmi_method_enable(wblock, false);
+ list_del(&wblock->list);
+ put_device(&wblock->dev.dev);
+ }
+ }
+
+ kfree(obj);
+
+ return 0;
+}
+
+/*
+ * WMI can have EmbeddedControl access regions. In which case, we just want to
+ * hand these off to the EC driver.
+ */
+static acpi_status
+acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address,
+ u32 bits, u64 *value,
+ void *handler_context, void *region_context)
+{
+ int result = 0, i = 0;
+ u8 temp = 0;
+
+ if ((address > 0xFF) || !value)
+ return AE_BAD_PARAMETER;
+
+ if (function != ACPI_READ && function != ACPI_WRITE)
+ return AE_BAD_PARAMETER;
+
+ if (bits != 8)
+ return AE_BAD_PARAMETER;
+
+ if (function == ACPI_READ) {
+ result = ec_read(address, &temp);
+ (*value) |= ((u64)temp) << i;
+ } else {
+ temp = 0xff & ((*value) >> i);
+ result = ec_write(address, temp);
+ }
+
+ switch (result) {
+ case -EINVAL:
+ return AE_BAD_PARAMETER;
+ case -ENODEV:
+ return AE_NOT_FOUND;
+ case -ETIME:
+ return AE_TIME;
+ default:
+ return AE_OK;
+ }
+}
+
+static void acpi_wmi_notify_handler(acpi_handle handle, u32 event,
+ void *context)
+{
+ struct wmi_block *wblock = NULL, *iter;
+
+ list_for_each_entry(iter, &wmi_block_list, list) {
+ struct guid_block *block = &iter->gblock;
+
+ if (iter->acpi_device->handle == handle &&
+ (block->flags & ACPI_WMI_EVENT) &&
+ (block->notify_id == event)) {
+ wblock = iter;
+ break;
+ }
+ }
+
+ if (!wblock)
+ return;
+
+ /* If a driver is bound, then notify the driver. */
+ if (test_bit(WMI_PROBED, &wblock->flags) && wblock->dev.dev.driver) {
+ struct wmi_driver *driver = drv_to_wdrv(wblock->dev.dev.driver);
+ struct acpi_buffer evdata = { ACPI_ALLOCATE_BUFFER, NULL };
+ acpi_status status;
+
+ if (!driver->no_notify_data) {
+ status = get_event_data(wblock, &evdata);
+ if (ACPI_FAILURE(status)) {
+ dev_warn(&wblock->dev.dev, "failed to get event data\n");
+ return;
+ }
+ }
+
+ if (driver->notify)
+ driver->notify(&wblock->dev, evdata.pointer);
+
+ kfree(evdata.pointer);
+ } else if (wblock->handler) {
+ /* Legacy handler */
+ wblock->handler(event, wblock->handler_data);
+ }
+
+ if (debug_event)
+ pr_info("DEBUG: GUID %pUL event 0x%02X\n", &wblock->gblock.guid, event);
+
+ acpi_bus_generate_netlink_event(
+ wblock->acpi_device->pnp.device_class,
+ dev_name(&wblock->dev.dev),
+ event, 0);
+}
+
+static void acpi_wmi_remove(struct platform_device *device)
+{
+ struct acpi_device *acpi_device = ACPI_COMPANION(&device->dev);
+
+ acpi_remove_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY,
+ acpi_wmi_notify_handler);
+ acpi_remove_address_space_handler(acpi_device->handle,
+ ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler);
+ wmi_free_devices(acpi_device);
+ device_unregister(dev_get_drvdata(&device->dev));
+}
+
+static int acpi_wmi_probe(struct platform_device *device)
+{
+ struct acpi_device *acpi_device;
+ struct device *wmi_bus_dev;
+ acpi_status status;
+ int error;
+
+ acpi_device = ACPI_COMPANION(&device->dev);
+ if (!acpi_device) {
+ dev_err(&device->dev, "ACPI companion is missing\n");
+ return -ENODEV;
+ }
+
+ status = acpi_install_address_space_handler(acpi_device->handle,
+ ACPI_ADR_SPACE_EC,
+ &acpi_wmi_ec_space_handler,
+ NULL, NULL);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&device->dev, "Error installing EC region handler\n");
+ return -ENODEV;
+ }
+
+ status = acpi_install_notify_handler(acpi_device->handle,
+ ACPI_ALL_NOTIFY,
+ acpi_wmi_notify_handler,
+ NULL);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&device->dev, "Error installing notify handler\n");
+ error = -ENODEV;
+ goto err_remove_ec_handler;
+ }
+
+ wmi_bus_dev = device_create(&wmi_bus_class, &device->dev, MKDEV(0, 0),
+ NULL, "wmi_bus-%s", dev_name(&device->dev));
+ if (IS_ERR(wmi_bus_dev)) {
+ error = PTR_ERR(wmi_bus_dev);
+ goto err_remove_notify_handler;
+ }
+ dev_set_drvdata(&device->dev, wmi_bus_dev);
+
+ error = parse_wdg(wmi_bus_dev, acpi_device);
+ if (error) {
+ pr_err("Failed to parse WDG method\n");
+ goto err_remove_busdev;
+ }
+
+ return 0;
+
+err_remove_busdev:
+ device_unregister(wmi_bus_dev);
+
+err_remove_notify_handler:
+ acpi_remove_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY,
+ acpi_wmi_notify_handler);
+
+err_remove_ec_handler:
+ acpi_remove_address_space_handler(acpi_device->handle,
+ ACPI_ADR_SPACE_EC,
+ &acpi_wmi_ec_space_handler);
+
+ return error;
+}
+
+int __must_check __wmi_driver_register(struct wmi_driver *driver,
+ struct module *owner)
+{
+ driver->driver.owner = owner;
+ driver->driver.bus = &wmi_bus_type;
+
+ return driver_register(&driver->driver);
+}
+EXPORT_SYMBOL(__wmi_driver_register);
+
+/**
+ * wmi_driver_unregister() - Unregister a WMI driver
+ * @driver: WMI driver to unregister
+ *
+ * Unregisters a WMI driver from the WMI bus.
+ */
+void wmi_driver_unregister(struct wmi_driver *driver)
+{
+ driver_unregister(&driver->driver);
+}
+EXPORT_SYMBOL(wmi_driver_unregister);
+
+static struct platform_driver acpi_wmi_driver = {
+ .driver = {
+ .name = "acpi-wmi",
+ .acpi_match_table = wmi_device_ids,
+ },
+ .probe = acpi_wmi_probe,
+ .remove_new = acpi_wmi_remove,
+};
+
+static int __init acpi_wmi_init(void)
+{
+ int error;
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ error = class_register(&wmi_bus_class);
+ if (error)
+ return error;
+
+ error = bus_register(&wmi_bus_type);
+ if (error)
+ goto err_unreg_class;
+
+ error = platform_driver_register(&acpi_wmi_driver);
+ if (error) {
+ pr_err("Error loading mapper\n");
+ goto err_unreg_bus;
+ }
+
+ return 0;
+
+err_unreg_bus:
+ bus_unregister(&wmi_bus_type);
+
+err_unreg_class:
+ class_unregister(&wmi_bus_class);
+
+ return error;
+}
+
+static void __exit acpi_wmi_exit(void)
+{
+ platform_driver_unregister(&acpi_wmi_driver);
+ bus_unregister(&wmi_bus_type);
+ class_unregister(&wmi_bus_class);
+}
+
+subsys_initcall_sync(acpi_wmi_init);
+module_exit(acpi_wmi_exit);