| // 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/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"); |
| |
| 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_GUID_DUPLICATED, |
| WMI_NO_EVENT_DATA, |
| }; |
| |
| struct wmi_block { |
| struct wmi_device dev; |
| struct list_head list; |
| 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; |
| }; |
| |
| |
| /* |
| * 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) |
| #define dev_to_wdev(__dev) container_of_const(__dev, struct wmi_device, 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; |
| } |
| |
| 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 = ¶m, |
| }; |
| |
| return acpi_evaluate_object(wblock->acpi_device->handle, "_WED", &input, out); |
| } |
| |
| 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 int wmidev_match_notify_id(struct device *dev, const void *data) |
| { |
| struct wmi_block *wblock = dev_to_wblock(dev); |
| const u32 *notify_id = 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 (wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *notify_id) |
| return 1; |
| |
| return 0; |
| } |
| |
| static const struct bus_type wmi_bus_type; |
| |
| 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 dev_to_wdev(dev); |
| } |
| |
| static struct wmi_device *wmi_find_event_by_notify_id(const u32 notify_id) |
| { |
| struct device *dev; |
| |
| dev = bus_find_device(&wmi_bus_type, NULL, ¬ify_id, wmidev_match_notify_id); |
| 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; |
| 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; |
| struct wmi_device *wdev; |
| acpi_status status; |
| |
| wdev = wmi_find_device_by_guid(guid_string); |
| if (IS_ERR(wdev)) |
| return AE_ERROR; |
| |
| wblock = container_of(wdev, struct wmi_block, dev); |
| status = __query_block(wblock, instance, out); |
| |
| 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; |
| |
| status = wmidev_block_set(wdev, instance, in); |
| 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; |
| 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(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 (ACPI_FAILURE(wmi_method_enable(wblock, true))) |
| 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 (ACPI_FAILURE(wmi_method_enable(wblock, false))) |
| 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_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; |
| struct wmi_device *wdev; |
| acpi_status status; |
| |
| wdev = wmi_find_event_by_notify_id(event); |
| if (IS_ERR(wdev)) |
| return AE_NOT_FOUND; |
| |
| wblock = container_of(wdev, struct wmi_block, dev); |
| status = get_event_data(wblock, out); |
| |
| wmi_device_put(wdev); |
| |
| return status; |
| } |
| 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) |
| { |
| 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); |
| |
| #define drv_to_wdrv(__drv) container_of_const(__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 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 = 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->dev.driver_override); |
| kfree(wblock); |
| } |
| |
| static int wmi_dev_match(struct device *dev, const struct device_driver *driver) |
| { |
| const 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; |
| |
| /* 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 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; |
| |
| /* 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 (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) { |
| if (ACPI_FAILURE(wmi_method_enable(wblock, false))) |
| dev_warn(dev, "Failed to disable device\n"); |
| |
| 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 = drv_to_wdrv(dev->driver); |
| |
| down_write(&wblock->notify_lock); |
| wblock->driver_ready = false; |
| up_write(&wblock->notify_lock); |
| |
| 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 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, |
| }; |
| |
| 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) |
| { |
| char method[WMI_ACPI_METHOD_NAME_SIZE]; |
| struct acpi_device_info *info; |
| acpi_handle method_handle; |
| acpi_status status; |
| 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) { |
| 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) { |
| dev_set_name(&wblock->dev.dev, "%pUL-%d", &wblock->gblock.guid, count); |
| set_bit(WMI_GUID_DUPLICATED, &wblock->flags); |
| } else { |
| dev_set_name(&wblock->dev.dev, "%pUL", &wblock->gblock.guid); |
| } |
| |
| 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; |
| } |
| |
| list_add_tail(&wblock->list, &wmi_block_list); |
| |
| retval = wmi_add_device(pdev, &wblock->dev); |
| if (retval) { |
| dev_err(wmi_bus_dev, "failed to register %pUL\n", |
| &wblock->gblock.guid); |
| |
| list_del(&wblock->list); |
| 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 }; |
| acpi_status status; |
| |
| if (test_bit(WMI_NO_EVENT_DATA, &wblock->flags)) { |
| *obj = NULL; |
| return 0; |
| } |
| |
| status = get_event_data(wblock, &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 = drv_to_wdrv(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; |
| u32 *event = data; |
| int ret; |
| |
| if (!(wblock->gblock.flags & ACPI_WMI_EVENT && wblock->gblock.notify_id == *event)) |
| return 0; |
| |
| down_read(&wblock->notify_lock); |
| /* The WMI driver notify handler conflicts with the legacy WMI handler. |
| * Because of this the WMI driver notify handler takes precedence. |
| */ |
| if (wblock->dev.dev.driver && wblock->driver_ready) { |
| ret = wmi_get_notify_data(wblock, &obj); |
| if (ret >= 0) { |
| wmi_notify_driver(wblock, obj); |
| kfree(obj); |
| } |
| } else { |
| if (wblock->handler) { |
| wblock->handler(*event, wblock->handler_data); |
| } else { |
| /* 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. |
| * |
| * Because of this we need this seemingly useless call to |
| * wmi_get_notify_data() which in turn evaluates _WED. |
| */ |
| ret = wmi_get_notify_data(wblock, &obj); |
| if (ret >= 0) |
| kfree(obj); |
| } |
| |
| } |
| up_read(&wblock->notify_lock); |
| |
| 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) |
| { |
| struct wmi_block *wblock = dev_to_wblock(dev); |
| |
| list_del(&wblock->list); |
| device_unregister(dev); |
| |
| 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_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); |