/*
* 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;
INIT_LIST_HEAD(&wmi_blocks.list);
if (acpi_disabled)
return -ENODEV;
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);
