diff options
Diffstat (limited to 'drivers/acpi/wmi.c')
| -rw-r--r-- | drivers/acpi/wmi.c | 710 |
1 files changed, 710 insertions, 0 deletions
diff --git a/drivers/acpi/wmi.c b/drivers/acpi/wmi.c new file mode 100644 index 000000000000..36b84ab418dd --- /dev/null +++ b/drivers/acpi/wmi.c @@ -0,0 +1,710 @@ +/* + * 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> + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or (at + * your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/list.h> +#include <linux/acpi.h> +#include <acpi/acpi_bus.h> +#include <acpi/acpi_drivers.h> + +ACPI_MODULE_NAME("wmi"); +MODULE_AUTHOR("Carlos Corbacho"); +MODULE_DESCRIPTION("ACPI-WMI Mapping Driver"); +MODULE_LICENSE("GPL"); + +#define ACPI_WMI_CLASS "wmi" + +#undef PREFIX +#define PREFIX "ACPI: WMI: " + +static DEFINE_MUTEX(wmi_data_lock); + +struct guid_block { + char guid[16]; + union { + char object_id[2]; + struct { + unsigned char notify_id; + unsigned char reserved; + }; + }; + u8 instance_count; + u8 flags; +}; + +struct wmi_block { + struct list_head list; + struct guid_block gblock; + acpi_handle handle; + wmi_notify_handler handler; + void *handler_data; +}; + +static struct wmi_block wmi_blocks; + +/* + * If the GUID data block is marked as expensive, we must enable and + * explicitily disable data collection. + */ +#define ACPI_WMI_EXPENSIVE 0x1 +#define ACPI_WMI_METHOD 0x2 /* GUID is a method */ +#define ACPI_WMI_STRING 0x4 /* GUID takes & returns a string */ +#define ACPI_WMI_EVENT 0x8 /* GUID is an event */ + +static int acpi_wmi_remove(struct acpi_device *device, int type); +static int acpi_wmi_add(struct acpi_device *device); + +static const struct acpi_device_id wmi_device_ids[] = { + {"PNP0C14", 0}, + {"pnp0c14", 0}, + {"", 0}, +}; +MODULE_DEVICE_TABLE(acpi, wmi_device_ids); + +static struct acpi_driver acpi_wmi_driver = { + .name = "wmi", + .class = ACPI_WMI_CLASS, + .ids = wmi_device_ids, + .ops = { + .add = acpi_wmi_add, + .remove = acpi_wmi_remove, + }, +}; + +/* + * GUID parsing functions + */ + +/** + * wmi_parse_hexbyte - Convert a ASCII hex number to a byte + * @src: Pointer to at least 2 characters to convert. + * + * Convert a two character ASCII hex string to a number. + * + * Return: 0-255 Success, the byte was parsed correctly + * -1 Error, an invalid character was supplied + */ +static int wmi_parse_hexbyte(const u8 *src) +{ + unsigned int x; /* For correct wrapping */ + int h; + + /* high part */ + x = src[0]; + if (x - '0' <= '9' - '0') { + h = x - '0'; + } else if (x - 'a' <= 'f' - 'a') { + h = x - 'a' + 10; + } else if (x - 'A' <= 'F' - 'A') { + h = x - 'A' + 10; + } else { + return -1; + } + h <<= 4; + + /* low part */ + x = src[1]; + if (x - '0' <= '9' - '0') + return h | (x - '0'); + if (x - 'a' <= 'f' - 'a') + return h | (x - 'a' + 10); + if (x - 'A' <= 'F' - 'A') + return h | (x - 'A' + 10); + return -1; +} + +/** + * wmi_swap_bytes - Rearrange GUID bytes to match GUID binary + * @src: Memory block holding binary GUID (16 bytes) + * @dest: Memory block to hold byte swapped binary GUID (16 bytes) + * + * Byte swap a binary GUID to match it's real GUID value + */ +static void wmi_swap_bytes(u8 *src, u8 *dest) +{ + int i; + + for (i = 0; i <= 3; i++) + memcpy(dest + i, src + (3 - i), 1); + + for (i = 0; i <= 1; i++) + memcpy(dest + 4 + i, src + (5 - i), 1); + + for (i = 0; i <= 1; i++) + memcpy(dest + 6 + i, src + (7 - i), 1); + + memcpy(dest + 8, src + 8, 8); +} + +/** + * wmi_parse_guid - Convert GUID from ASCII to binary + * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba + * @dest: Memory block to hold binary GUID (16 bytes) + * + * N.B. The GUID need not be NULL terminated. + * + * Return: 'true' @dest contains binary GUID + * 'false' @dest contents are undefined + */ +static bool wmi_parse_guid(const u8 *src, u8 *dest) +{ + static const int size[] = { 4, 2, 2, 2, 6 }; + int i, j, v; + + if (src[8] != '-' || src[13] != '-' || + src[18] != '-' || src[23] != '-') + return false; + + for (j = 0; j < 5; j++, src++) { + for (i = 0; i < size[j]; i++, src += 2, *dest++ = v) { + v = wmi_parse_hexbyte(src); + if (v < 0) + return false; + } + } + + return true; +} + +static bool find_guid(const char *guid_string, struct wmi_block **out) +{ + char tmp[16], guid_input[16]; + struct wmi_block *wblock; + struct guid_block *block; + struct list_head *p; + + wmi_parse_guid(guid_string, tmp); + wmi_swap_bytes(tmp, guid_input); + + list_for_each(p, &wmi_blocks.list) { + wblock = list_entry(p, struct wmi_block, list); + block = &wblock->gblock; + + if (memcmp(block->guid, guid_input, 16) == 0) { + if (out) + *out = wblock; + return 1; + } + } + return 0; +} + +/* + * Exported WMI functions + */ +/** + * wmi_evaluate_method - Evaluate a WMI method + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba + * @instance: Instance index + * @method_id: Method ID to call + * &in: Buffer containing input for the method call + * &out: Empty buffer to return the method results + * + * Call an ACPI-WMI method + */ +acpi_status wmi_evaluate_method(const char *guid_string, u8 instance, +u32 method_id, const struct acpi_buffer *in, struct acpi_buffer *out) +{ + struct guid_block *block = NULL; + struct wmi_block *wblock = NULL; + acpi_handle handle; + acpi_status status; + struct acpi_object_list input; + union acpi_object params[3]; + char method[4] = "WM"; + + if (!find_guid(guid_string, &wblock)) + return AE_BAD_ADDRESS; + + block = &wblock->gblock; + handle = wblock->handle; + + if (!block->flags & ACPI_WMI_METHOD) + return AE_BAD_DATA; + + if (block->instance_count < instance) + return AE_BAD_PARAMETER; + + input.count = 2; + input.pointer = params; + params[0].type = ACPI_TYPE_INTEGER; + params[0].integer.value = instance; + params[1].type = ACPI_TYPE_INTEGER; + params[1].integer.value = method_id; + + if (in) { + input.count = 3; + + if (block->flags & ACPI_WMI_STRING) { + params[2].type = ACPI_TYPE_STRING; + } else { + params[2].type = ACPI_TYPE_BUFFER; + } + params[2].buffer.length = in->length; + params[2].buffer.pointer = in->pointer; + } + + strncat(method, block->object_id, 2); + + status = acpi_evaluate_object(handle, method, &input, out); + + return status; +} +EXPORT_SYMBOL_GPL(wmi_evaluate_method); + +/** + * wmi_query_block - Return contents of a WMI block + * @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 + * + * Return the contents of an ACPI-WMI data block to a buffer + */ +acpi_status wmi_query_block(const char *guid_string, u8 instance, +struct acpi_buffer *out) +{ + struct guid_block *block = NULL; + struct wmi_block *wblock = NULL; + acpi_handle handle; + acpi_status status, wc_status = AE_ERROR; + struct acpi_object_list input, wc_input; + union acpi_object wc_params[1], wq_params[1]; + char method[4]; + char wc_method[4] = "WC"; + + if (!guid_string || !out) + return AE_BAD_PARAMETER; + + if (!find_guid(guid_string, &wblock)) + return AE_BAD_ADDRESS; + + block = &wblock->gblock; + handle = wblock->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_BAD_ADDRESS; + + input.count = 1; + input.pointer = wq_params; + wq_params[0].type = ACPI_TYPE_INTEGER; + wq_params[0].integer.value = instance; + + /* + * If ACPI_WMI_EXPENSIVE, call the relevant WCxx method first to + * enable collection. + */ + if (block->flags & ACPI_WMI_EXPENSIVE) { + wc_input.count = 1; + wc_input.pointer = wc_params; + wc_params[0].type = ACPI_TYPE_INTEGER; + wc_params[0].integer.value = 1; + + strncat(wc_method, block->object_id, 2); + + /* + * 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_evaluate_object(handle, wc_method, + &wc_input, NULL); + } + + strcpy(method, "WQ"); + strncat(method, block->object_id, 2); + + status = acpi_evaluate_object(handle, method, NULL, 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) && wc_status) { + wc_params[0].integer.value = 0; + status = acpi_evaluate_object(handle, + wc_method, &wc_input, NULL); + } + + return status; +} +EXPORT_SYMBOL_GPL(wmi_query_block); + +/** + * wmi_set_block - Write to a WMI block + * @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 + */ +acpi_status wmi_set_block(const char *guid_string, u8 instance, +const struct acpi_buffer *in) +{ + struct guid_block *block = NULL; + struct wmi_block *wblock = NULL; + acpi_handle handle; + struct acpi_object_list input; + union acpi_object params[2]; + char method[4] = "WS"; + + if (!guid_string || !in) + return AE_BAD_DATA; + + if (!find_guid(guid_string, &wblock)) + return AE_BAD_ADDRESS; + + block = &wblock->gblock; + handle = wblock->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_BAD_ADDRESS; + + input.count = 2; + input.pointer = params; + params[0].type = ACPI_TYPE_INTEGER; + params[0].integer.value = instance; + + if (block->flags & ACPI_WMI_STRING) { + params[1].type = ACPI_TYPE_STRING; + } else { + params[1].type = ACPI_TYPE_BUFFER; + } + params[1].buffer.length = in->length; + params[1].buffer.pointer = in->pointer; + + strncat(method, block->object_id, 2); + + return acpi_evaluate_object(handle, method, &input, NULL); +} +EXPORT_SYMBOL_GPL(wmi_set_block); + +/** + * wmi_install_notify_handler - Register handler for WMI events + * @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. + */ +acpi_status wmi_install_notify_handler(const char *guid, +wmi_notify_handler handler, void *data) +{ + struct wmi_block *block; + + if (!guid || !handler) + return AE_BAD_PARAMETER; + + find_guid(guid, &block); + if (!block) + return AE_NOT_EXIST; + + if (block->handler) + return AE_ALREADY_ACQUIRED; + + block->handler = handler; + block->handler_data = data; + + return AE_OK; +} +EXPORT_SYMBOL_GPL(wmi_install_notify_handler); + +/** + * wmi_uninstall_notify_handler - Unregister handler for WMI events + * + * Unregister handler for events sent to the ACPI-WMI mapper device. + */ +acpi_status wmi_remove_notify_handler(const char *guid) +{ + struct wmi_block *block; + + if (!guid) + return AE_BAD_PARAMETER; + + find_guid(guid, &block); + if (!block) + return AE_NOT_EXIST; + + if (!block->handler) + return AE_NULL_ENTRY; + + block->handler = NULL; + block->handler_data = NULL; + + return AE_OK; +} +EXPORT_SYMBOL_GPL(wmi_remove_notify_handler); + +/** + * wmi_get_event_data - Get WMI data associated with an event + * + * @event - Event to find + * &out - Buffer to hold event data + * + * Returns extra data associated with an event in WMI. + */ +acpi_status wmi_get_event_data(u32 event, struct acpi_buffer *out) +{ + struct acpi_object_list input; + union acpi_object params[1]; + struct guid_block *gblock; + struct wmi_block *wblock; + struct list_head *p; + + input.count = 1; + input.pointer = params; + params[0].type = ACPI_TYPE_INTEGER; + params[0].integer.value = event; + + list_for_each(p, &wmi_blocks.list) { + wblock = list_entry(p, struct wmi_block, list); + gblock = &wblock->gblock; + + if ((gblock->flags & ACPI_WMI_EVENT) && + (gblock->notify_id == event)) + return acpi_evaluate_object(wblock->handle, "_WED", + &input, out); + } + + return AE_NOT_FOUND; +} +EXPORT_SYMBOL_GPL(wmi_get_event_data); + +/** + * wmi_has_guid - Check if a GUID is available + * @guid_string: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba + * + * Check if a given GUID is defined by _WDG + */ +bool wmi_has_guid(const char *guid_string) +{ + return find_guid(guid_string, NULL); +} +EXPORT_SYMBOL_GPL(wmi_has_guid); + +/* + * Parse the _WDG method for the GUID data blocks + */ +static __init acpi_status parse_wdg(acpi_handle handle) +{ + struct acpi_buffer out = {ACPI_ALLOCATE_BUFFER, NULL}; + union acpi_object *obj; + struct guid_block *gblock; + struct wmi_block *wblock; + acpi_status status; + u32 i, total; + + status = acpi_evaluate_object(handle, "_WDG", NULL, &out); + + if (ACPI_FAILURE(status)) + return status; + + obj = (union acpi_object *) out.pointer; + + if (obj->type != ACPI_TYPE_BUFFER) + return AE_ERROR; + + total = obj->buffer.length / sizeof(struct guid_block); + + gblock = kzalloc(obj->buffer.length, GFP_KERNEL); + if (!gblock) + return AE_NO_MEMORY; + + memcpy(gblock, obj->buffer.pointer, obj->buffer.length); + + for (i = 0; i < total; i++) { + wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL); + if (!wblock) + return AE_NO_MEMORY; + + wblock->gblock = gblock[i]; + wblock->handle = handle; + list_add_tail(&wblock->list, &wmi_blocks.list); + } + + kfree(out.pointer); + kfree(gblock); + + return status; +} + +/* + * WMI can have EmbeddedControl access regions. In which case, we just want to + * hand these off to the EC driver. + */ +static acpi_status +acpi_wmi_ec_space_handler(u32 function, acpi_physical_address address, + u32 bits, acpi_integer * value, + void *handler_context, void *region_context) +{ + int result = 0, i = 0; + u8 temp = 0; + + if ((address > 0xFF) || !value) + return AE_BAD_PARAMETER; + + if (function != ACPI_READ && function != ACPI_WRITE) + return AE_BAD_PARAMETER; + + if (bits != 8) + return AE_BAD_PARAMETER; + + if (function == ACPI_READ) { + result = ec_read(address, &temp); + (*value) |= ((acpi_integer)temp) << i; + } else { + temp = 0xff & ((*value) >> i); + result = ec_write(address, temp); + } + + switch (result) { + case -EINVAL: + return AE_BAD_PARAMETER; + break; + case -ENODEV: + return AE_NOT_FOUND; + break; + case -ETIME: + return AE_TIME; + break; + default: + return AE_OK; + } +} + +static void acpi_wmi_notify(acpi_handle handle, u32 event, void *data) +{ + struct guid_block *block; + struct wmi_block *wblock; + struct list_head *p; + struct acpi_device *device = data; + + list_for_each(p, &wmi_blocks.list) { + wblock = list_entry(p, struct wmi_block, list); + block = &wblock->gblock; + + if ((block->flags & ACPI_WMI_EVENT) && + (block->notify_id == event)) { + if (wblock->handler) + wblock->handler(event, wblock->handler_data); + + acpi_bus_generate_netlink_event( + device->pnp.device_class, device->dev.bus_id, + event, 0); + break; + } + } +} + +static int acpi_wmi_remove(struct acpi_device *device, int type) +{ + acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, + acpi_wmi_notify); + + acpi_remove_address_space_handler(device->handle, + ACPI_ADR_SPACE_EC, &acpi_wmi_ec_space_handler); + + return 0; +} + +static int __init acpi_wmi_add(struct acpi_device *device) +{ + acpi_status status; + int result = 0; + + status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, + acpi_wmi_notify, device); + if (ACPI_FAILURE(status)) { + printk(KERN_ERR PREFIX "Error installing notify handler\n"); + return -ENODEV; + } + + status = acpi_install_address_space_handler(device->handle, + ACPI_ADR_SPACE_EC, + &acpi_wmi_ec_space_handler, + NULL, NULL); + if (ACPI_FAILURE(status)) + return -ENODEV; + + status = parse_wdg(device->handle); + if (ACPI_FAILURE(status)) { + printk(KERN_ERR PREFIX "Error installing EC region handler\n"); + return -ENODEV; + } + + return result; +} + +static int __init acpi_wmi_init(void) +{ + acpi_status result; + + if (acpi_disabled) + return -ENODEV; + + INIT_LIST_HEAD(&wmi_blocks.list); + + result = acpi_bus_register_driver(&acpi_wmi_driver); + + if (result < 0) { + printk(KERN_INFO PREFIX "Error loading mapper\n"); + } else { + printk(KERN_INFO PREFIX "Mapper loaded\n"); + } + + return result; +} + +static void __exit acpi_wmi_exit(void) +{ + struct list_head *p, *tmp; + struct wmi_block *wblock; + + acpi_bus_unregister_driver(&acpi_wmi_driver); + + list_for_each_safe(p, tmp, &wmi_blocks.list) { + wblock = list_entry(p, struct wmi_block, list); + + list_del(p); + kfree(wblock); + } + + printk(KERN_INFO PREFIX "Mapper unloaded\n"); +} + +subsys_initcall(acpi_wmi_init); +module_exit(acpi_wmi_exit); |
