.. kernel-doc:: include/linux/wmi.h
:internal:
-.. kernel-doc:: drivers/platform/x86/wmi.c
+.. kernel-doc:: drivers/platform/wmi/core.c
:export:
F: Documentation/ABI/testing/sysfs-bus-wmi
F: Documentation/driver-api/wmi.rst
F: Documentation/wmi/
-F: drivers/platform/x86/wmi.c
+F: drivers/platform/wmi/
F: include/uapi/linux/wmi.h
ACRN HYPERVISOR SERVICE MODULE
source "drivers/platform/x86/Kconfig"
source "drivers/platform/arm64/Kconfig"
+
+source "drivers/platform/wmi/Kconfig"
obj-$(CONFIG_CZNIC_PLATFORMS) += cznic/
obj-$(CONFIG_SURFACE_PLATFORMS) += surface/
obj-$(CONFIG_ARM64_PLATFORM_DEVICES) += arm64/
+obj-$(CONFIG_ACPI_WMI) += wmi/
--- /dev/null
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# ACPI WMI Core
+#
+
+menuconfig ACPI_WMI
+ tristate "ACPI-WMI support"
+ depends on ACPI && X86
+ help
+ This option enables support for the ACPI-WMI driver core.
+
+ The ACPI-WMI interface is a proprietary extension of ACPI allowing
+ the platform firmware to expose WMI (Windows Management Instrumentation)
+ objects used for managing various aspects of the underlying system.
+ Mapping between ACPI control methods and WMI objects happens through
+ special mapper devices (PNP0C14) defined inside the ACPI tables.
+
+ Enabling this option is necessary for building the vendor specific
+ ACPI-WMI client drivers for Acer, Dell an HP machines (among others).
+
+ It is safe to enable this option even for machines that do not contain
+ any ACPI-WMI mapper devices at all.
+
+if ACPI_WMI
+
+config ACPI_WMI_LEGACY_DEVICE_NAMES
+ bool "Use legacy WMI device naming scheme"
+ help
+ Say Y here to force the WMI driver core to use the old WMI device naming
+ scheme when creating WMI devices. Doing so might be necessary for some
+ userspace applications but will cause the registration of WMI devices with
+ the same GUID to fail in some corner cases.
+
+endif # ACPI_WMI
--- /dev/null
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Makefile for linux/drivers/platform/wmi
+# ACPI WMI core
+#
+
+wmi-y := core.o
+obj-$(CONFIG_ACPI_WMI) += wmi.o
--- /dev/null
+// 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/idr.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/uuid.h>
+#include <linux/wmi.h>
+#include <linux/fs.h>
+
+MODULE_AUTHOR("Carlos Corbacho");
+MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
+MODULE_LICENSE("GPL");
+
+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_GUID_DUPLICATED,
+ WMI_NO_EVENT_DATA,
+};
+
+struct wmi_block {
+ struct wmi_device dev;
+ struct guid_block gblock;
+ struct acpi_device *acpi_device;
+ struct rw_semaphore notify_lock; /* Protects notify callback add/remove */
+ wmi_notify_handler handler;
+ void *handler_data;
+ bool driver_ready;
+ unsigned long flags;
+};
+
+struct wmi_guid_count_context {
+ const guid_t *guid;
+ int count;
+};
+
+static DEFINE_IDA(wmi_ida);
+
+/*
+ * 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 const struct acpi_device_id wmi_device_ids[] = {
+ {"PNP0C14", 0},
+ {"pnp0c14", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
+
+#define dev_to_wblock(__dev) container_of_const(__dev, struct wmi_block, dev.dev)
+
+/*
+ * GUID parsing functions
+ */
+
+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;
+}
+
+#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 int wmidev_match_guid(struct device *dev, const void *data)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ const guid_t *guid = data;
+
+ /* Legacy GUID-based functions are restricted to only see
+ * a single WMI device for each GUID.
+ */
+ if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags))
+ return 0;
+
+ if (guid_equal(guid, &wblock->gblock.guid))
+ return 1;
+
+ return 0;
+}
+
+static const struct bus_type wmi_bus_type;
+
+static const struct device_type wmi_type_event;
+
+static const struct device_type wmi_type_method;
+
+static int wmi_device_enable(struct wmi_device *wdev, bool enable)
+{
+ struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
+ char method[WMI_ACPI_METHOD_NAME_SIZE];
+ acpi_handle handle;
+ acpi_status status;
+
+ if (wblock->dev.dev.type == &wmi_type_method)
+ return 0;
+
+ if (wblock->dev.dev.type == &wmi_type_event) {
+ /*
+ * Windows always enables/disables WMI events, even when they are
+ * not marked as being expensive. We follow this behavior for
+ * compatibility reasons.
+ */
+ snprintf(method, sizeof(method), "WE%02X", wblock->gblock.notify_id);
+ } else {
+ if (!(wblock->gblock.flags & ACPI_WMI_EXPENSIVE))
+ return 0;
+
+ get_acpi_method_name(wblock, 'C', method);
+ }
+
+ /*
+ * Not all WMI devices marked as expensive actually implement the
+ * necessary ACPI method. Ignore this missing ACPI method to match
+ * the behaviour of the Windows driver.
+ */
+ status = acpi_get_handle(wblock->acpi_device->handle, method, &handle);
+ if (ACPI_FAILURE(status))
+ return 0;
+
+ status = acpi_execute_simple_method(handle, NULL, enable);
+ if (ACPI_FAILURE(status))
+ return -EIO;
+
+ return 0;
+}
+
+static struct wmi_device *wmi_find_device_by_guid(const char *guid_string)
+{
+ struct device *dev;
+ guid_t guid;
+ int ret;
+
+ ret = guid_parse(guid_string, &guid);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ dev = bus_find_device(&wmi_bus_type, NULL, &guid, wmidev_match_guid);
+ if (!dev)
+ return ERR_PTR(-ENODEV);
+
+ return to_wmi_device(dev);
+}
+
+static void wmi_device_put(struct wmi_device *wdev)
+{
+ put_device(&wdev->dev);
+}
+
+/*
+ * Exported WMI functions
+ */
+
+/**
+ * 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_device *wdev;
+ int ret;
+
+ wdev = wmi_find_device_by_guid(guid_string);
+ if (IS_ERR(wdev))
+ return PTR_ERR(wdev);
+
+ ret = wmidev_instance_count(wdev);
+ wmi_device_put(wdev);
+
+ return ret;
+}
+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: Mandatory 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_device *wdev;
+ acpi_status status;
+
+ wdev = wmi_find_device_by_guid(guid_string);
+ if (IS_ERR(wdev))
+ return AE_ERROR;
+
+ status = wmidev_evaluate_method(wdev, instance, method_id, in, out);
+
+ wmi_device_put(wdev);
+
+ return status;
+}
+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: Mandatory 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 (!in)
+ return AE_BAD_DATA;
+
+ if (!(block->flags & ACPI_WMI_METHOD))
+ return AE_BAD_DATA;
+
+ if (block->instance_count <= instance)
+ return AE_BAD_PARAMETER;
+
+ input.count = 3;
+ 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 (wblock->gblock.flags & ACPI_WMI_STRING) {
+ params[2].type = ACPI_TYPE_STRING;
+ params[2].string.length = in->length;
+ params[2].string.pointer = in->pointer;
+ } else {
+ params[2].type = ACPI_TYPE_BUFFER;
+ 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;
+ struct acpi_object_list input;
+ union acpi_object wq_params[1];
+ 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;
+
+ get_acpi_method_name(wblock, 'Q', method);
+
+ return acpi_evaluate_object(handle, method, &input, out);
+}
+
+/**
+ * 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;
+ struct wmi_device *wdev;
+ acpi_status status;
+
+ wdev = wmi_find_device_by_guid(guid_string);
+ if (IS_ERR(wdev))
+ return AE_ERROR;
+
+ if (wmi_device_enable(wdev, true) < 0)
+ dev_warn(&wdev->dev, "Failed to enable device\n");
+
+ wblock = container_of(wdev, struct wmi_block, dev);
+ status = __query_block(wblock, instance, out);
+
+ if (wmi_device_enable(wdev, false) < 0)
+ dev_warn(&wdev->dev, "Failed to disable device\n");
+
+ wmi_device_put(wdev);
+
+ return status;
+}
+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_device *wdev;
+ acpi_status status;
+
+ wdev = wmi_find_device_by_guid(guid_string);
+ if (IS_ERR(wdev))
+ return AE_ERROR;
+
+ if (wmi_device_enable(wdev, true) < 0)
+ dev_warn(&wdev->dev, "Failed to enable device\n");
+
+ status = wmidev_block_set(wdev, instance, in);
+
+ if (wmi_device_enable(wdev, false) < 0)
+ dev_warn(&wdev->dev, "Failed to disable device\n");
+
+ wmi_device_put(wdev);
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(wmi_set_block);
+
+/**
+ * wmidev_block_set - Write to a WMI block
+ * @wdev: A wmi bus device from a driver
+ * @instance: Instance index
+ * @in: Buffer containing new values for the data block
+ *
+ * Write contents of the input buffer to an ACPI-WMI data block.
+ *
+ * Return: acpi_status signaling success or error.
+ */
+acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in)
+{
+ struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
+ acpi_handle handle = wblock->acpi_device->handle;
+ struct guid_block *block = &wblock->gblock;
+ char method[WMI_ACPI_METHOD_NAME_SIZE];
+ struct acpi_object_list input;
+ union acpi_object params[2];
+
+ if (!in)
+ return AE_BAD_DATA;
+
+ 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;
+
+ if (wblock->gblock.flags & ACPI_WMI_STRING) {
+ params[1].type = ACPI_TYPE_STRING;
+ params[1].string.length = in->length;
+ params[1].string.pointer = in->pointer;
+ } else {
+ params[1].type = ACPI_TYPE_BUFFER;
+ 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(wmidev_block_set);
+
+/**
+ * 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 *wblock;
+ struct wmi_device *wdev;
+ acpi_status status;
+
+ wdev = wmi_find_device_by_guid(guid);
+ if (IS_ERR(wdev))
+ return AE_ERROR;
+
+ wblock = container_of(wdev, struct wmi_block, dev);
+
+ down_write(&wblock->notify_lock);
+ if (wblock->handler) {
+ status = AE_ALREADY_ACQUIRED;
+ } else {
+ wblock->handler = handler;
+ wblock->handler_data = data;
+
+ if (wmi_device_enable(wdev, true) < 0)
+ dev_warn(&wblock->dev.dev, "Failed to enable device\n");
+
+ status = AE_OK;
+ }
+ up_write(&wblock->notify_lock);
+
+ wmi_device_put(wdev);
+
+ 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 *wblock;
+ struct wmi_device *wdev;
+ acpi_status status;
+
+ wdev = wmi_find_device_by_guid(guid);
+ if (IS_ERR(wdev))
+ return AE_ERROR;
+
+ wblock = container_of(wdev, struct wmi_block, dev);
+
+ down_write(&wblock->notify_lock);
+ if (!wblock->handler) {
+ status = AE_NULL_ENTRY;
+ } else {
+ if (wmi_device_enable(wdev, false) < 0)
+ dev_warn(&wblock->dev.dev, "Failed to disable device\n");
+
+ wblock->handler = NULL;
+ wblock->handler_data = NULL;
+
+ status = AE_OK;
+ }
+ up_write(&wblock->notify_lock);
+
+ wmi_device_put(wdev);
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
+
+/**
+ * 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)
+{
+ struct wmi_device *wdev;
+
+ wdev = wmi_find_device_by_guid(guid_string);
+ if (IS_ERR(wdev))
+ return false;
+
+ wmi_device_put(wdev);
+
+ return true;
+}
+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;
+ struct wmi_device *wdev;
+ char *uid;
+
+ wdev = wmi_find_device_by_guid(guid_string);
+ if (IS_ERR(wdev))
+ return NULL;
+
+ wblock = container_of(wdev, struct wmi_block, dev);
+ uid = acpi_device_uid(wblock->acpi_device);
+
+ wmi_device_put(wdev);
+
+ return uid;
+}
+EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
+
+/*
+ * 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 ssize_t driver_override_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct wmi_device *wdev = to_wmi_device(dev);
+ ssize_t ret;
+
+ device_lock(dev);
+ ret = sysfs_emit(buf, "%s\n", wdev->driver_override);
+ device_unlock(dev);
+
+ return ret;
+}
+
+static ssize_t driver_override_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct wmi_device *wdev = to_wmi_device(dev);
+ int ret;
+
+ ret = driver_set_override(dev, &wdev->driver_override, buf, count);
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+static DEVICE_ATTR_RW(driver_override);
+
+static struct attribute *wmi_attrs[] = {
+ &dev_attr_modalias.attr,
+ &dev_attr_guid.attr,
+ &dev_attr_instance_count.attr,
+ &dev_attr_expensive.attr,
+ &dev_attr_driver_override.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 = to_wmi_device(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->dev.driver_override);
+ kfree(wblock);
+}
+
+static int wmi_dev_match(struct device *dev, const struct device_driver *driver)
+{
+ const struct wmi_driver *wmi_driver = to_wmi_driver(driver);
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ const struct wmi_device_id *id = wmi_driver->id_table;
+
+ /* When driver_override is set, only bind to the matching driver */
+ if (wblock->dev.driver_override)
+ return !strcmp(wblock->dev.driver_override, driver->name);
+
+ 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 void wmi_dev_disable(void *data)
+{
+ struct device *dev = data;
+
+ if (wmi_device_enable(to_wmi_device(dev), false) < 0)
+ dev_warn(dev, "Failed to disable device\n");
+}
+
+static int wmi_dev_probe(struct device *dev)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ struct wmi_driver *wdriver = to_wmi_driver(dev->driver);
+ int ret;
+
+ /* Some older WMI drivers will break if instantiated multiple times,
+ * so they are blocked from probing WMI devices with a duplicated GUID.
+ *
+ * New WMI drivers should support being instantiated multiple times.
+ */
+ if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags) && !wdriver->no_singleton) {
+ dev_warn(dev, "Legacy driver %s cannot be instantiated multiple times\n",
+ dev->driver->name);
+
+ return -ENODEV;
+ }
+
+ if (wdriver->notify) {
+ if (test_bit(WMI_NO_EVENT_DATA, &wblock->flags) && !wdriver->no_notify_data)
+ return -ENODEV;
+ }
+
+ if (wmi_device_enable(to_wmi_device(dev), true) < 0)
+ dev_warn(dev, "failed to enable device -- probing anyway\n");
+
+ /*
+ * We have to make sure that all devres-managed resources are released first because
+ * some might still want to access the underlying WMI device.
+ */
+ ret = devm_add_action_or_reset(dev, wmi_dev_disable, dev);
+ if (ret < 0)
+ return ret;
+
+ if (wdriver->probe) {
+ ret = wdriver->probe(to_wmi_device(dev),
+ find_guid_context(wblock, wdriver));
+ if (ret)
+ return ret;
+ }
+
+ down_write(&wblock->notify_lock);
+ wblock->driver_ready = true;
+ up_write(&wblock->notify_lock);
+
+ return 0;
+}
+
+static void wmi_dev_remove(struct device *dev)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ struct wmi_driver *wdriver = to_wmi_driver(dev->driver);
+
+ down_write(&wblock->notify_lock);
+ wblock->driver_ready = false;
+ up_write(&wblock->notify_lock);
+
+ if (wdriver->remove)
+ wdriver->remove(to_wmi_device(dev));
+}
+
+static void wmi_dev_shutdown(struct device *dev)
+{
+ struct wmi_driver *wdriver;
+ struct wmi_block *wblock;
+
+ if (dev->driver) {
+ wdriver = to_wmi_driver(dev->driver);
+ wblock = dev_to_wblock(dev);
+
+ /*
+ * Some machines return bogus WMI event data when disabling
+ * the WMI event. Because of this we must prevent the associated
+ * WMI driver from receiving new WMI events before disabling it.
+ */
+ down_write(&wblock->notify_lock);
+ wblock->driver_ready = false;
+ up_write(&wblock->notify_lock);
+
+ if (wdriver->shutdown)
+ wdriver->shutdown(to_wmi_device(dev));
+
+ /*
+ * We still need to disable the WMI device here since devres-managed resources
+ * like wmi_dev_disable() will not be release during shutdown.
+ */
+ if (wmi_device_enable(to_wmi_device(dev), false) < 0)
+ dev_warn(dev, "Failed to disable device\n");
+ }
+}
+
+static struct class wmi_bus_class = {
+ .name = "wmi_bus",
+};
+
+static const 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,
+ .shutdown = wmi_dev_shutdown,
+};
+
+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,
+};
+
+static int wmi_count_guids(struct device *dev, void *data)
+{
+ struct wmi_guid_count_context *context = data;
+ struct wmi_block *wblock = dev_to_wblock(dev);
+
+ if (guid_equal(&wblock->gblock.guid, context->guid))
+ context->count++;
+
+ return 0;
+}
+
+static int guid_count(const guid_t *guid)
+{
+ struct wmi_guid_count_context context = {
+ .guid = guid,
+ .count = 0,
+ };
+ int ret;
+
+ ret = bus_for_each_dev(&wmi_bus_type, NULL, &context, wmi_count_guids);
+ if (ret < 0)
+ return ret;
+
+ return context.count;
+}
+
+static int wmi_dev_set_name(struct wmi_block *wblock, int count)
+{
+ if (IS_ENABLED(CONFIG_ACPI_WMI_LEGACY_DEVICE_NAMES)) {
+ if (count)
+ return dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid,
+ count);
+ else
+ return dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid);
+ }
+
+ return dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, wblock->dev.dev.id);
+}
+
+static int wmi_create_device(struct device *wmi_bus_dev,
+ struct wmi_block *wblock,
+ struct acpi_device *device)
+{
+ char method[WMI_ACPI_METHOD_NAME_SIZE];
+ struct acpi_device_info *info;
+ acpi_handle method_handle;
+ acpi_status status;
+ int count, ret;
+
+ if (wblock->gblock.flags & ACPI_WMI_EVENT) {
+ wblock->dev.dev.type = &wmi_type_event;
+ goto out_init;
+ }
+
+ if (wblock->gblock.flags & ACPI_WMI_METHOD) {
+ get_acpi_method_name(wblock, 'M', method);
+ if (!acpi_has_method(device->handle, method)) {
+ dev_warn(wmi_bus_dev,
+ FW_BUG "%s method block execution control method not found\n",
+ method);
+
+ return -ENXIO;
+ }
+
+ wblock->dev.dev.type = &wmi_type_method;
+ 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);
+ status = acpi_get_handle(device->handle, method, &method_handle);
+ if (ACPI_FAILURE(status)) {
+ dev_warn(wmi_bus_dev,
+ FW_BUG "%s data block query control method not found\n",
+ method);
+
+ return -ENXIO;
+ }
+
+ status = acpi_get_object_info(method_handle, &info);
+ if (ACPI_FAILURE(status))
+ return -EIO;
+
+ 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);
+ if (acpi_has_method(device->handle, method))
+ wblock->dev.setable = true;
+
+ out_init:
+ init_rwsem(&wblock->notify_lock);
+ wblock->driver_ready = false;
+ wblock->dev.dev.bus = &wmi_bus_type;
+ wblock->dev.dev.parent = wmi_bus_dev;
+
+ count = guid_count(&wblock->gblock.guid);
+ if (count < 0)
+ return count;
+
+ if (count)
+ set_bit(WMI_GUID_DUPLICATED, &wblock->flags);
+
+ ret = ida_alloc(&wmi_ida, GFP_KERNEL);
+ if (ret < 0)
+ return ret;
+
+ wblock->dev.dev.id = ret;
+ ret = wmi_dev_set_name(wblock, count);
+ if (ret < 0) {
+ ida_free(&wmi_ida, wblock->dev.dev.id);
+ return ret;
+ }
+
+ device_initialize(&wblock->dev.dev);
+
+ return 0;
+}
+
+static int wmi_add_device(struct platform_device *pdev, struct wmi_device *wdev)
+{
+ struct device_link *link;
+
+ /*
+ * Many aggregate WMI drivers do not use -EPROBE_DEFER when they
+ * are unable to find a WMI device during probe, instead they require
+ * all WMI devices associated with an platform device to become available
+ * at once. This device link thus prevents WMI drivers from probing until
+ * the associated platform device has finished probing (and has registered
+ * all discovered WMI devices).
+ */
+
+ link = device_link_add(&wdev->dev, &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER);
+ if (!link)
+ return -EINVAL;
+
+ return device_add(&wdev->dev);
+}
+
+/*
+ * Parse the _WDG method for the GUID data blocks
+ */
+static int parse_wdg(struct device *wmi_bus_dev, struct platform_device *pdev)
+{
+ struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
+ struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
+ const struct guid_block *gblock;
+ bool event_data_available;
+ struct wmi_block *wblock;
+ 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;
+ }
+
+ event_data_available = acpi_has_method(device->handle, "_WED");
+ gblock = (const struct guid_block *)obj->buffer.pointer;
+ total = obj->buffer.length / sizeof(struct guid_block);
+
+ for (i = 0; i < total; i++) {
+ if (!gblock[i].instance_count) {
+ dev_info(wmi_bus_dev, FW_INFO "%pUL has zero instances\n", &gblock[i].guid);
+ continue;
+ }
+
+ wblock = kzalloc(sizeof(*wblock), GFP_KERNEL);
+ if (!wblock)
+ continue;
+
+ wblock->acpi_device = device;
+ wblock->gblock = gblock[i];
+ if (gblock[i].flags & ACPI_WMI_EVENT && !event_data_available)
+ set_bit(WMI_NO_EVENT_DATA, &wblock->flags);
+
+ retval = wmi_create_device(wmi_bus_dev, wblock, device);
+ if (retval) {
+ kfree(wblock);
+ continue;
+ }
+
+ retval = wmi_add_device(pdev, &wblock->dev);
+ if (retval) {
+ dev_err(wmi_bus_dev, "failed to register %pUL\n",
+ &wblock->gblock.guid);
+
+ ida_free(&wmi_ida, wblock->dev.dev.id);
+ put_device(&wblock->dev.dev);
+ }
+ }
+
+ kfree(obj);
+
+ return 0;
+}
+
+static int wmi_get_notify_data(struct wmi_block *wblock, union acpi_object **obj)
+{
+ struct acpi_buffer data = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object param = {
+ .integer = {
+ .type = ACPI_TYPE_INTEGER,
+ .value = wblock->gblock.notify_id,
+ }
+ };
+ struct acpi_object_list input = {
+ .count = 1,
+ .pointer = ¶m,
+ };
+ acpi_status status;
+
+ status = acpi_evaluate_object(wblock->acpi_device->handle, "_WED", &input, &data);
+ if (ACPI_FAILURE(status)) {
+ dev_warn(&wblock->dev.dev, "Failed to get event data\n");
+ return -EIO;
+ }
+
+ *obj = data.pointer;
+
+ return 0;
+}
+
+static void wmi_notify_driver(struct wmi_block *wblock, union acpi_object *obj)
+{
+ struct wmi_driver *driver = to_wmi_driver(wblock->dev.dev.driver);
+
+ if (!obj && !driver->no_notify_data) {
+ dev_warn(&wblock->dev.dev, "Event contains no event data\n");
+ return;
+ }
+
+ if (driver->notify)
+ driver->notify(&wblock->dev, obj);
+}
+
+static int wmi_notify_device(struct device *dev, void *data)
+{
+ struct wmi_block *wblock = dev_to_wblock(dev);
+ union acpi_object *obj = NULL;
+ u32 *event = data;
+ int ret;
+
+ if (!(wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *event))
+ return 0;
+
+ /* The ACPI WMI specification says that _WED should be
+ * evaluated every time an notification is received, even
+ * if no consumers are present.
+ *
+ * Some firmware implementations actually depend on this
+ * by using a queue for events which will fill up if the
+ * WMI driver core stops evaluating _WED due to missing
+ * WMI event consumers.
+ */
+ if (!test_bit(WMI_NO_EVENT_DATA, &wblock->flags)) {
+ ret = wmi_get_notify_data(wblock, &obj);
+ if (ret < 0)
+ return -EIO;
+ }
+
+ down_read(&wblock->notify_lock);
+
+ if (wblock->dev.dev.driver && wblock->driver_ready)
+ wmi_notify_driver(wblock, obj);
+
+ if (wblock->handler)
+ wblock->handler(obj, wblock->handler_data);
+
+ up_read(&wblock->notify_lock);
+
+ kfree(obj);
+
+ acpi_bus_generate_netlink_event("wmi", acpi_dev_name(wblock->acpi_device), *event, 0);
+
+ return -EBUSY;
+}
+
+static void acpi_wmi_notify_handler(acpi_handle handle, u32 event, void *context)
+{
+ struct device *wmi_bus_dev = context;
+
+ device_for_each_child(wmi_bus_dev, &event, wmi_notify_device);
+}
+
+static int wmi_remove_device(struct device *dev, void *data)
+{
+ int id = dev->id;
+
+ device_unregister(dev);
+ ida_free(&wmi_ida, id);
+
+ return 0;
+}
+
+static void acpi_wmi_remove(struct platform_device *device)
+{
+ struct device *wmi_bus_device = dev_get_drvdata(&device->dev);
+
+ device_for_each_child_reverse(wmi_bus_device, NULL, wmi_remove_device);
+}
+
+static void acpi_wmi_remove_notify_handler(void *data)
+{
+ struct acpi_device *acpi_device = data;
+
+ acpi_remove_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY, acpi_wmi_notify_handler);
+}
+
+static void acpi_wmi_remove_bus_device(void *data)
+{
+ struct device *wmi_bus_dev = data;
+
+ device_unregister(wmi_bus_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;
+ }
+
+ 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))
+ return PTR_ERR(wmi_bus_dev);
+
+ error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_bus_device, wmi_bus_dev);
+ if (error < 0)
+ return error;
+
+ dev_set_drvdata(&device->dev, wmi_bus_dev);
+
+ status = acpi_install_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY,
+ acpi_wmi_notify_handler, wmi_bus_dev);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&device->dev, "Error installing notify handler\n");
+ return -ENODEV;
+ }
+ error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_notify_handler,
+ acpi_device);
+ if (error < 0)
+ return error;
+
+ error = parse_wdg(wmi_bus_dev, device);
+ if (error) {
+ dev_err(&device->dev, "Failed to parse _WDG method\n");
+ return error;
+ }
+
+ return 0;
+}
+
+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 = 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);
if X86_PLATFORM_DEVICES
-config ACPI_WMI
- tristate "WMI"
- depends on ACPI
- help
- This driver adds support for the ACPI-WMI (Windows Management
- Instrumentation) mapper device (PNP0C14) found on some systems.
-
- ACPI-WMI is a proprietary extension to ACPI to expose parts of the
- ACPI firmware to userspace - this is done through various vendor
- defined methods and data blocks in a PNP0C14 device, which are then
- made available for userspace to call.
-
- The implementation of this in Linux currently only exposes this to
- other kernel space drivers.
-
- This driver is a required dependency to build the firmware specific
- drivers needed on many machines, including Acer and HP laptops.
-
- It is safe to enable this driver even if your DSDT doesn't define
- any ACPI-WMI devices.
-
-config ACPI_WMI_LEGACY_DEVICE_NAMES
- bool "Use legacy WMI device naming scheme"
- depends on ACPI_WMI
- help
- Say Y here to force the WMI driver core to use the old WMI device naming
- scheme when creating WMI devices. Doing so might be necessary for some
- userspace applications but will cause the registration of WMI devices with
- the same GUID to fail in some corner cases.
-
config WMI_BMOF
tristate "WMI embedded Binary MOF driver"
depends on ACPI_WMI
#
# Windows Management Interface
-obj-$(CONFIG_ACPI_WMI) += wmi.o
obj-$(CONFIG_WMI_BMOF) += wmi-bmof.o
# WMI drivers
+++ /dev/null
-// 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/idr.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/rwsem.h>
-#include <linux/slab.h>
-#include <linux/sysfs.h>
-#include <linux/types.h>
-#include <linux/uuid.h>
-#include <linux/wmi.h>
-#include <linux/fs.h>
-
-MODULE_AUTHOR("Carlos Corbacho");
-MODULE_DESCRIPTION("ACPI-WMI Mapping Driver");
-MODULE_LICENSE("GPL");
-
-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_GUID_DUPLICATED,
- WMI_NO_EVENT_DATA,
-};
-
-struct wmi_block {
- struct wmi_device dev;
- struct guid_block gblock;
- struct acpi_device *acpi_device;
- struct rw_semaphore notify_lock; /* Protects notify callback add/remove */
- wmi_notify_handler handler;
- void *handler_data;
- bool driver_ready;
- unsigned long flags;
-};
-
-struct wmi_guid_count_context {
- const guid_t *guid;
- int count;
-};
-
-static DEFINE_IDA(wmi_ida);
-
-/*
- * 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 const struct acpi_device_id wmi_device_ids[] = {
- {"PNP0C14", 0},
- {"pnp0c14", 0},
- { }
-};
-MODULE_DEVICE_TABLE(acpi, wmi_device_ids);
-
-#define dev_to_wblock(__dev) container_of_const(__dev, struct wmi_block, dev.dev)
-
-/*
- * GUID parsing functions
- */
-
-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;
-}
-
-#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 int wmidev_match_guid(struct device *dev, const void *data)
-{
- struct wmi_block *wblock = dev_to_wblock(dev);
- const guid_t *guid = data;
-
- /* Legacy GUID-based functions are restricted to only see
- * a single WMI device for each GUID.
- */
- if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags))
- return 0;
-
- if (guid_equal(guid, &wblock->gblock.guid))
- return 1;
-
- return 0;
-}
-
-static const struct bus_type wmi_bus_type;
-
-static const struct device_type wmi_type_event;
-
-static const struct device_type wmi_type_method;
-
-static int wmi_device_enable(struct wmi_device *wdev, bool enable)
-{
- struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
- char method[WMI_ACPI_METHOD_NAME_SIZE];
- acpi_handle handle;
- acpi_status status;
-
- if (wblock->dev.dev.type == &wmi_type_method)
- return 0;
-
- if (wblock->dev.dev.type == &wmi_type_event) {
- /*
- * Windows always enables/disables WMI events, even when they are
- * not marked as being expensive. We follow this behavior for
- * compatibility reasons.
- */
- snprintf(method, sizeof(method), "WE%02X", wblock->gblock.notify_id);
- } else {
- if (!(wblock->gblock.flags & ACPI_WMI_EXPENSIVE))
- return 0;
-
- get_acpi_method_name(wblock, 'C', method);
- }
-
- /*
- * Not all WMI devices marked as expensive actually implement the
- * necessary ACPI method. Ignore this missing ACPI method to match
- * the behaviour of the Windows driver.
- */
- status = acpi_get_handle(wblock->acpi_device->handle, method, &handle);
- if (ACPI_FAILURE(status))
- return 0;
-
- status = acpi_execute_simple_method(handle, NULL, enable);
- if (ACPI_FAILURE(status))
- return -EIO;
-
- return 0;
-}
-
-static struct wmi_device *wmi_find_device_by_guid(const char *guid_string)
-{
- struct device *dev;
- guid_t guid;
- int ret;
-
- ret = guid_parse(guid_string, &guid);
- if (ret < 0)
- return ERR_PTR(ret);
-
- dev = bus_find_device(&wmi_bus_type, NULL, &guid, wmidev_match_guid);
- if (!dev)
- return ERR_PTR(-ENODEV);
-
- return to_wmi_device(dev);
-}
-
-static void wmi_device_put(struct wmi_device *wdev)
-{
- put_device(&wdev->dev);
-}
-
-/*
- * Exported WMI functions
- */
-
-/**
- * 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_device *wdev;
- int ret;
-
- wdev = wmi_find_device_by_guid(guid_string);
- if (IS_ERR(wdev))
- return PTR_ERR(wdev);
-
- ret = wmidev_instance_count(wdev);
- wmi_device_put(wdev);
-
- return ret;
-}
-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: Mandatory 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_device *wdev;
- acpi_status status;
-
- wdev = wmi_find_device_by_guid(guid_string);
- if (IS_ERR(wdev))
- return AE_ERROR;
-
- status = wmidev_evaluate_method(wdev, instance, method_id, in, out);
-
- wmi_device_put(wdev);
-
- return status;
-}
-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: Mandatory 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 (!in)
- return AE_BAD_DATA;
-
- if (!(block->flags & ACPI_WMI_METHOD))
- return AE_BAD_DATA;
-
- if (block->instance_count <= instance)
- return AE_BAD_PARAMETER;
-
- input.count = 3;
- 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 (wblock->gblock.flags & ACPI_WMI_STRING) {
- params[2].type = ACPI_TYPE_STRING;
- params[2].string.length = in->length;
- params[2].string.pointer = in->pointer;
- } else {
- params[2].type = ACPI_TYPE_BUFFER;
- 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;
- struct acpi_object_list input;
- union acpi_object wq_params[1];
- 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;
-
- get_acpi_method_name(wblock, 'Q', method);
-
- return acpi_evaluate_object(handle, method, &input, out);
-}
-
-/**
- * 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;
- struct wmi_device *wdev;
- acpi_status status;
-
- wdev = wmi_find_device_by_guid(guid_string);
- if (IS_ERR(wdev))
- return AE_ERROR;
-
- if (wmi_device_enable(wdev, true) < 0)
- dev_warn(&wdev->dev, "Failed to enable device\n");
-
- wblock = container_of(wdev, struct wmi_block, dev);
- status = __query_block(wblock, instance, out);
-
- if (wmi_device_enable(wdev, false) < 0)
- dev_warn(&wdev->dev, "Failed to disable device\n");
-
- wmi_device_put(wdev);
-
- return status;
-}
-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_device *wdev;
- acpi_status status;
-
- wdev = wmi_find_device_by_guid(guid_string);
- if (IS_ERR(wdev))
- return AE_ERROR;
-
- if (wmi_device_enable(wdev, true) < 0)
- dev_warn(&wdev->dev, "Failed to enable device\n");
-
- status = wmidev_block_set(wdev, instance, in);
-
- if (wmi_device_enable(wdev, false) < 0)
- dev_warn(&wdev->dev, "Failed to disable device\n");
-
- wmi_device_put(wdev);
-
- return status;
-}
-EXPORT_SYMBOL_GPL(wmi_set_block);
-
-/**
- * wmidev_block_set - Write to a WMI block
- * @wdev: A wmi bus device from a driver
- * @instance: Instance index
- * @in: Buffer containing new values for the data block
- *
- * Write contents of the input buffer to an ACPI-WMI data block.
- *
- * Return: acpi_status signaling success or error.
- */
-acpi_status wmidev_block_set(struct wmi_device *wdev, u8 instance, const struct acpi_buffer *in)
-{
- struct wmi_block *wblock = container_of(wdev, struct wmi_block, dev);
- acpi_handle handle = wblock->acpi_device->handle;
- struct guid_block *block = &wblock->gblock;
- char method[WMI_ACPI_METHOD_NAME_SIZE];
- struct acpi_object_list input;
- union acpi_object params[2];
-
- if (!in)
- return AE_BAD_DATA;
-
- 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;
-
- if (wblock->gblock.flags & ACPI_WMI_STRING) {
- params[1].type = ACPI_TYPE_STRING;
- params[1].string.length = in->length;
- params[1].string.pointer = in->pointer;
- } else {
- params[1].type = ACPI_TYPE_BUFFER;
- 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(wmidev_block_set);
-
-/**
- * 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 *wblock;
- struct wmi_device *wdev;
- acpi_status status;
-
- wdev = wmi_find_device_by_guid(guid);
- if (IS_ERR(wdev))
- return AE_ERROR;
-
- wblock = container_of(wdev, struct wmi_block, dev);
-
- down_write(&wblock->notify_lock);
- if (wblock->handler) {
- status = AE_ALREADY_ACQUIRED;
- } else {
- wblock->handler = handler;
- wblock->handler_data = data;
-
- if (wmi_device_enable(wdev, true) < 0)
- dev_warn(&wblock->dev.dev, "Failed to enable device\n");
-
- status = AE_OK;
- }
- up_write(&wblock->notify_lock);
-
- wmi_device_put(wdev);
-
- 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 *wblock;
- struct wmi_device *wdev;
- acpi_status status;
-
- wdev = wmi_find_device_by_guid(guid);
- if (IS_ERR(wdev))
- return AE_ERROR;
-
- wblock = container_of(wdev, struct wmi_block, dev);
-
- down_write(&wblock->notify_lock);
- if (!wblock->handler) {
- status = AE_NULL_ENTRY;
- } else {
- if (wmi_device_enable(wdev, false) < 0)
- dev_warn(&wblock->dev.dev, "Failed to disable device\n");
-
- wblock->handler = NULL;
- wblock->handler_data = NULL;
-
- status = AE_OK;
- }
- up_write(&wblock->notify_lock);
-
- wmi_device_put(wdev);
-
- return status;
-}
-EXPORT_SYMBOL_GPL(wmi_remove_notify_handler);
-
-/**
- * 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)
-{
- struct wmi_device *wdev;
-
- wdev = wmi_find_device_by_guid(guid_string);
- if (IS_ERR(wdev))
- return false;
-
- wmi_device_put(wdev);
-
- return true;
-}
-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;
- struct wmi_device *wdev;
- char *uid;
-
- wdev = wmi_find_device_by_guid(guid_string);
- if (IS_ERR(wdev))
- return NULL;
-
- wblock = container_of(wdev, struct wmi_block, dev);
- uid = acpi_device_uid(wblock->acpi_device);
-
- wmi_device_put(wdev);
-
- return uid;
-}
-EXPORT_SYMBOL_GPL(wmi_get_acpi_device_uid);
-
-/*
- * 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 ssize_t driver_override_show(struct device *dev, struct device_attribute *attr,
- char *buf)
-{
- struct wmi_device *wdev = to_wmi_device(dev);
- ssize_t ret;
-
- device_lock(dev);
- ret = sysfs_emit(buf, "%s\n", wdev->driver_override);
- device_unlock(dev);
-
- return ret;
-}
-
-static ssize_t driver_override_store(struct device *dev, struct device_attribute *attr,
- const char *buf, size_t count)
-{
- struct wmi_device *wdev = to_wmi_device(dev);
- int ret;
-
- ret = driver_set_override(dev, &wdev->driver_override, buf, count);
- if (ret < 0)
- return ret;
-
- return count;
-}
-static DEVICE_ATTR_RW(driver_override);
-
-static struct attribute *wmi_attrs[] = {
- &dev_attr_modalias.attr,
- &dev_attr_guid.attr,
- &dev_attr_instance_count.attr,
- &dev_attr_expensive.attr,
- &dev_attr_driver_override.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 = to_wmi_device(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->dev.driver_override);
- kfree(wblock);
-}
-
-static int wmi_dev_match(struct device *dev, const struct device_driver *driver)
-{
- const struct wmi_driver *wmi_driver = to_wmi_driver(driver);
- struct wmi_block *wblock = dev_to_wblock(dev);
- const struct wmi_device_id *id = wmi_driver->id_table;
-
- /* When driver_override is set, only bind to the matching driver */
- if (wblock->dev.driver_override)
- return !strcmp(wblock->dev.driver_override, driver->name);
-
- 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 void wmi_dev_disable(void *data)
-{
- struct device *dev = data;
-
- if (wmi_device_enable(to_wmi_device(dev), false) < 0)
- dev_warn(dev, "Failed to disable device\n");
-}
-
-static int wmi_dev_probe(struct device *dev)
-{
- struct wmi_block *wblock = dev_to_wblock(dev);
- struct wmi_driver *wdriver = to_wmi_driver(dev->driver);
- int ret;
-
- /* Some older WMI drivers will break if instantiated multiple times,
- * so they are blocked from probing WMI devices with a duplicated GUID.
- *
- * New WMI drivers should support being instantiated multiple times.
- */
- if (test_bit(WMI_GUID_DUPLICATED, &wblock->flags) && !wdriver->no_singleton) {
- dev_warn(dev, "Legacy driver %s cannot be instantiated multiple times\n",
- dev->driver->name);
-
- return -ENODEV;
- }
-
- if (wdriver->notify) {
- if (test_bit(WMI_NO_EVENT_DATA, &wblock->flags) && !wdriver->no_notify_data)
- return -ENODEV;
- }
-
- if (wmi_device_enable(to_wmi_device(dev), true) < 0)
- dev_warn(dev, "failed to enable device -- probing anyway\n");
-
- /*
- * We have to make sure that all devres-managed resources are released first because
- * some might still want to access the underlying WMI device.
- */
- ret = devm_add_action_or_reset(dev, wmi_dev_disable, dev);
- if (ret < 0)
- return ret;
-
- if (wdriver->probe) {
- ret = wdriver->probe(to_wmi_device(dev),
- find_guid_context(wblock, wdriver));
- if (ret)
- return ret;
- }
-
- down_write(&wblock->notify_lock);
- wblock->driver_ready = true;
- up_write(&wblock->notify_lock);
-
- return 0;
-}
-
-static void wmi_dev_remove(struct device *dev)
-{
- struct wmi_block *wblock = dev_to_wblock(dev);
- struct wmi_driver *wdriver = to_wmi_driver(dev->driver);
-
- down_write(&wblock->notify_lock);
- wblock->driver_ready = false;
- up_write(&wblock->notify_lock);
-
- if (wdriver->remove)
- wdriver->remove(to_wmi_device(dev));
-}
-
-static void wmi_dev_shutdown(struct device *dev)
-{
- struct wmi_driver *wdriver;
- struct wmi_block *wblock;
-
- if (dev->driver) {
- wdriver = to_wmi_driver(dev->driver);
- wblock = dev_to_wblock(dev);
-
- /*
- * Some machines return bogus WMI event data when disabling
- * the WMI event. Because of this we must prevent the associated
- * WMI driver from receiving new WMI events before disabling it.
- */
- down_write(&wblock->notify_lock);
- wblock->driver_ready = false;
- up_write(&wblock->notify_lock);
-
- if (wdriver->shutdown)
- wdriver->shutdown(to_wmi_device(dev));
-
- /*
- * We still need to disable the WMI device here since devres-managed resources
- * like wmi_dev_disable() will not be release during shutdown.
- */
- if (wmi_device_enable(to_wmi_device(dev), false) < 0)
- dev_warn(dev, "Failed to disable device\n");
- }
-}
-
-static struct class wmi_bus_class = {
- .name = "wmi_bus",
-};
-
-static const 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,
- .shutdown = wmi_dev_shutdown,
-};
-
-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,
-};
-
-static int wmi_count_guids(struct device *dev, void *data)
-{
- struct wmi_guid_count_context *context = data;
- struct wmi_block *wblock = dev_to_wblock(dev);
-
- if (guid_equal(&wblock->gblock.guid, context->guid))
- context->count++;
-
- return 0;
-}
-
-static int guid_count(const guid_t *guid)
-{
- struct wmi_guid_count_context context = {
- .guid = guid,
- .count = 0,
- };
- int ret;
-
- ret = bus_for_each_dev(&wmi_bus_type, NULL, &context, wmi_count_guids);
- if (ret < 0)
- return ret;
-
- return context.count;
-}
-
-static int wmi_dev_set_name(struct wmi_block *wblock, int count)
-{
- if (IS_ENABLED(CONFIG_ACPI_WMI_LEGACY_DEVICE_NAMES)) {
- if (count)
- return dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid,
- count);
- else
- return dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid);
- }
-
- return dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, wblock->dev.dev.id);
-}
-
-static int wmi_create_device(struct device *wmi_bus_dev,
- struct wmi_block *wblock,
- struct acpi_device *device)
-{
- char method[WMI_ACPI_METHOD_NAME_SIZE];
- struct acpi_device_info *info;
- acpi_handle method_handle;
- acpi_status status;
- int count, ret;
-
- if (wblock->gblock.flags & ACPI_WMI_EVENT) {
- wblock->dev.dev.type = &wmi_type_event;
- goto out_init;
- }
-
- if (wblock->gblock.flags & ACPI_WMI_METHOD) {
- get_acpi_method_name(wblock, 'M', method);
- if (!acpi_has_method(device->handle, method)) {
- dev_warn(wmi_bus_dev,
- FW_BUG "%s method block execution control method not found\n",
- method);
-
- return -ENXIO;
- }
-
- wblock->dev.dev.type = &wmi_type_method;
- 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);
- status = acpi_get_handle(device->handle, method, &method_handle);
- if (ACPI_FAILURE(status)) {
- dev_warn(wmi_bus_dev,
- FW_BUG "%s data block query control method not found\n",
- method);
-
- return -ENXIO;
- }
-
- status = acpi_get_object_info(method_handle, &info);
- if (ACPI_FAILURE(status))
- return -EIO;
-
- 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);
- if (acpi_has_method(device->handle, method))
- wblock->dev.setable = true;
-
- out_init:
- init_rwsem(&wblock->notify_lock);
- wblock->driver_ready = false;
- wblock->dev.dev.bus = &wmi_bus_type;
- wblock->dev.dev.parent = wmi_bus_dev;
-
- count = guid_count(&wblock->gblock.guid);
- if (count < 0)
- return count;
-
- if (count)
- set_bit(WMI_GUID_DUPLICATED, &wblock->flags);
-
- ret = ida_alloc(&wmi_ida, GFP_KERNEL);
- if (ret < 0)
- return ret;
-
- wblock->dev.dev.id = ret;
- ret = wmi_dev_set_name(wblock, count);
- if (ret < 0) {
- ida_free(&wmi_ida, wblock->dev.dev.id);
- return ret;
- }
-
- device_initialize(&wblock->dev.dev);
-
- return 0;
-}
-
-static int wmi_add_device(struct platform_device *pdev, struct wmi_device *wdev)
-{
- struct device_link *link;
-
- /*
- * Many aggregate WMI drivers do not use -EPROBE_DEFER when they
- * are unable to find a WMI device during probe, instead they require
- * all WMI devices associated with an platform device to become available
- * at once. This device link thus prevents WMI drivers from probing until
- * the associated platform device has finished probing (and has registered
- * all discovered WMI devices).
- */
-
- link = device_link_add(&wdev->dev, &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER);
- if (!link)
- return -EINVAL;
-
- return device_add(&wdev->dev);
-}
-
-/*
- * Parse the _WDG method for the GUID data blocks
- */
-static int parse_wdg(struct device *wmi_bus_dev, struct platform_device *pdev)
-{
- struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
- struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL};
- const struct guid_block *gblock;
- bool event_data_available;
- struct wmi_block *wblock;
- 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;
- }
-
- event_data_available = acpi_has_method(device->handle, "_WED");
- gblock = (const struct guid_block *)obj->buffer.pointer;
- total = obj->buffer.length / sizeof(struct guid_block);
-
- for (i = 0; i < total; i++) {
- if (!gblock[i].instance_count) {
- dev_info(wmi_bus_dev, FW_INFO "%pUL has zero instances\n", &gblock[i].guid);
- continue;
- }
-
- wblock = kzalloc(sizeof(*wblock), GFP_KERNEL);
- if (!wblock)
- continue;
-
- wblock->acpi_device = device;
- wblock->gblock = gblock[i];
- if (gblock[i].flags & ACPI_WMI_EVENT && !event_data_available)
- set_bit(WMI_NO_EVENT_DATA, &wblock->flags);
-
- retval = wmi_create_device(wmi_bus_dev, wblock, device);
- if (retval) {
- kfree(wblock);
- continue;
- }
-
- retval = wmi_add_device(pdev, &wblock->dev);
- if (retval) {
- dev_err(wmi_bus_dev, "failed to register %pUL\n",
- &wblock->gblock.guid);
-
- ida_free(&wmi_ida, wblock->dev.dev.id);
- put_device(&wblock->dev.dev);
- }
- }
-
- kfree(obj);
-
- return 0;
-}
-
-static int wmi_get_notify_data(struct wmi_block *wblock, union acpi_object **obj)
-{
- struct acpi_buffer data = { ACPI_ALLOCATE_BUFFER, NULL };
- union acpi_object param = {
- .integer = {
- .type = ACPI_TYPE_INTEGER,
- .value = wblock->gblock.notify_id,
- }
- };
- struct acpi_object_list input = {
- .count = 1,
- .pointer = ¶m,
- };
- acpi_status status;
-
- status = acpi_evaluate_object(wblock->acpi_device->handle, "_WED", &input, &data);
- if (ACPI_FAILURE(status)) {
- dev_warn(&wblock->dev.dev, "Failed to get event data\n");
- return -EIO;
- }
-
- *obj = data.pointer;
-
- return 0;
-}
-
-static void wmi_notify_driver(struct wmi_block *wblock, union acpi_object *obj)
-{
- struct wmi_driver *driver = to_wmi_driver(wblock->dev.dev.driver);
-
- if (!obj && !driver->no_notify_data) {
- dev_warn(&wblock->dev.dev, "Event contains no event data\n");
- return;
- }
-
- if (driver->notify)
- driver->notify(&wblock->dev, obj);
-}
-
-static int wmi_notify_device(struct device *dev, void *data)
-{
- struct wmi_block *wblock = dev_to_wblock(dev);
- union acpi_object *obj = NULL;
- u32 *event = data;
- int ret;
-
- if (!(wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *event))
- return 0;
-
- /* The ACPI WMI specification says that _WED should be
- * evaluated every time an notification is received, even
- * if no consumers are present.
- *
- * Some firmware implementations actually depend on this
- * by using a queue for events which will fill up if the
- * WMI driver core stops evaluating _WED due to missing
- * WMI event consumers.
- */
- if (!test_bit(WMI_NO_EVENT_DATA, &wblock->flags)) {
- ret = wmi_get_notify_data(wblock, &obj);
- if (ret < 0)
- return -EIO;
- }
-
- down_read(&wblock->notify_lock);
-
- if (wblock->dev.dev.driver && wblock->driver_ready)
- wmi_notify_driver(wblock, obj);
-
- if (wblock->handler)
- wblock->handler(obj, wblock->handler_data);
-
- up_read(&wblock->notify_lock);
-
- kfree(obj);
-
- acpi_bus_generate_netlink_event("wmi", acpi_dev_name(wblock->acpi_device), *event, 0);
-
- return -EBUSY;
-}
-
-static void acpi_wmi_notify_handler(acpi_handle handle, u32 event, void *context)
-{
- struct device *wmi_bus_dev = context;
-
- device_for_each_child(wmi_bus_dev, &event, wmi_notify_device);
-}
-
-static int wmi_remove_device(struct device *dev, void *data)
-{
- int id = dev->id;
-
- device_unregister(dev);
- ida_free(&wmi_ida, id);
-
- return 0;
-}
-
-static void acpi_wmi_remove(struct platform_device *device)
-{
- struct device *wmi_bus_device = dev_get_drvdata(&device->dev);
-
- device_for_each_child_reverse(wmi_bus_device, NULL, wmi_remove_device);
-}
-
-static void acpi_wmi_remove_notify_handler(void *data)
-{
- struct acpi_device *acpi_device = data;
-
- acpi_remove_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY, acpi_wmi_notify_handler);
-}
-
-static void acpi_wmi_remove_bus_device(void *data)
-{
- struct device *wmi_bus_dev = data;
-
- device_unregister(wmi_bus_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;
- }
-
- 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))
- return PTR_ERR(wmi_bus_dev);
-
- error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_bus_device, wmi_bus_dev);
- if (error < 0)
- return error;
-
- dev_set_drvdata(&device->dev, wmi_bus_dev);
-
- status = acpi_install_notify_handler(acpi_device->handle, ACPI_ALL_NOTIFY,
- acpi_wmi_notify_handler, wmi_bus_dev);
- if (ACPI_FAILURE(status)) {
- dev_err(&device->dev, "Error installing notify handler\n");
- return -ENODEV;
- }
- error = devm_add_action_or_reset(&device->dev, acpi_wmi_remove_notify_handler,
- acpi_device);
- if (error < 0)
- return error;
-
- error = parse_wdg(wmi_bus_dev, device);
- if (error) {
- dev_err(&device->dev, "Failed to parse _WDG method\n");
- return error;
- }
-
- return 0;
-}
-
-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 = 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);
projects / ceph-client.git / commitdiff