- 根目录:
- drivers
- acpi
- utils.c
/*
* acpi_utils.c - ACPI Utility Functions ($Revision: 10 $)
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.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.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/hardirq.h>
#include <linux/acpi.h>
#include <linux/dynamic_debug.h>
#include "internal.h"
#define _COMPONENT ACPI_BUS_COMPONENT
ACPI_MODULE_NAME("utils");
/* --------------------------------------------------------------------------
Object Evaluation Helpers
-------------------------------------------------------------------------- */
static void
acpi_util_eval_error(acpi_handle h, acpi_string p, acpi_status s)
{
#ifdef ACPI_DEBUG_OUTPUT
char prefix[80] = {'\0'};
struct acpi_buffer buffer = {sizeof(prefix), prefix};
acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluate [%s.%s]: %s\n",
(char *) prefix, p, acpi_format_exception(s)));
#else
return;
#endif
}
acpi_status
acpi_extract_package(union acpi_object *package,
struct acpi_buffer *format, struct acpi_buffer *buffer)
{
u32 size_required = 0;
u32 tail_offset = 0;
char *format_string = NULL;
u32 format_count = 0;
u32 i = 0;
u8 *head = NULL;
u8 *tail = NULL;
if (!package || (package->type != ACPI_TYPE_PACKAGE)
|| (package->package.count < 1)) {
printk(KERN_WARNING PREFIX "Invalid package argument\n");
return AE_BAD_PARAMETER;
}
if (!format || !format->pointer || (format->length < 1)) {
printk(KERN_WARNING PREFIX "Invalid format argument\n");
return AE_BAD_PARAMETER;
}
if (!buffer) {
printk(KERN_WARNING PREFIX "Invalid buffer argument\n");
return AE_BAD_PARAMETER;
}
format_count = (format->length / sizeof(char)) - 1;
if (format_count > package->package.count) {
printk(KERN_WARNING PREFIX "Format specifies more objects [%d]"
" than exist in package [%d].\n",
format_count, package->package.count);
return AE_BAD_DATA;
}
format_string = format->pointer;
/*
* Calculate size_required.
*/
for (i = 0; i < format_count; i++) {
union acpi_object *element = &(package->package.elements[i]);
switch (element->type) {
case ACPI_TYPE_INTEGER:
switch (format_string[i]) {
case 'N':
size_required += sizeof(u64);
tail_offset += sizeof(u64);
break;
case 'S':
size_required +=
sizeof(char *) + sizeof(u64) +
sizeof(char);
tail_offset += sizeof(char *);
break;
default:
printk(KERN_WARNING PREFIX "Invalid package element"
" [%d]: got number, expecting"
" [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
break;
}
break;
case ACPI_TYPE_STRING:
case ACPI_TYPE_BUFFER:
switch (format_string[i]) {
case 'S':
size_required +=
sizeof(char *) +
(element->string.length * sizeof(char)) +
sizeof(char);
tail_offset += sizeof(char *);
break;
case 'B':
size_required +=
sizeof(u8 *) + element->buffer.length;
tail_offset += sizeof(u8 *);
break;
default:
printk(KERN_WARNING PREFIX "Invalid package element"
" [%d] got string/buffer,"
" expecting [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
break;
}
break;
case ACPI_TYPE_LOCAL_REFERENCE:
switch (format_string[i]) {
case 'R':
size_required += sizeof(void *);
tail_offset += sizeof(void *);
break;
default:
printk(KERN_WARNING PREFIX "Invalid package element"
" [%d] got reference,"
" expecting [%c]\n",
i, format_string[i]);
return AE_BAD_DATA;
break;
}
break;
case ACPI_TYPE_PACKAGE:
default:
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Found unsupported element at index=%d\n",
i));
/* TBD: handle nested packages... */
return AE_SUPPORT;
break;
}
}
/*
* Validate output buffer.
*/
if (buffer->length == ACPI_ALLOCATE_BUFFER) {
buffer->pointer = ACPI_ALLOCATE_ZEROED(size_required);
if (!buffer->pointer)
return AE_NO_MEMORY;
buffer->length = size_required;
} else {
if (buffer->length < size_required) {
buffer->length = size_required;
return AE_BUFFER_OVERFLOW;
} else if (buffer->length != size_required ||
!buffer->pointer) {
return AE_BAD_PARAMETER;
}
}
head = buffer->pointer;
tail = buffer->pointer + tail_offset;
/*
* Extract package data.
*/
for (i = 0; i < format_count; i++) {
u8 **pointer = NULL;
union acpi_object *element = &(package->package.elements[i]);
if (!element) {
return AE_BAD_DATA;
}
switch (element->type) {
case ACPI_TYPE_INTEGER:
switch (format_string[i]) {
case 'N':
*((u64 *) head) =
element->integer.value;
head += sizeof(u64);
break;
case 'S':
pointer = (u8 **) head;
*pointer = tail;
*((u64 *) tail) =
element->integer.value;
head += sizeof(u64 *);
tail += sizeof(u64);
/* NULL terminate string */
*tail = (char)0;
tail += sizeof(char);
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_STRING:
case ACPI_TYPE_BUFFER:
switch (format_string[i]) {
case 'S':
pointer = (u8 **) head;
*pointer = tail;
memcpy(tail, element->string.pointer,
element->string.length);
head += sizeof(char *);
tail += element->string.length * sizeof(char);
/* NULL terminate string */
*tail = (char)0;
tail += sizeof(char);
break;
case 'B':
pointer = (u8 **) head;
*pointer = tail;
memcpy(tail, element->buffer.pointer,
element->buffer.length);
head += sizeof(u8 *);
tail += element->buffer.length;
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_LOCAL_REFERENCE:
switch (format_string[i]) {
case 'R':
*(void **)head =
(void *)element->reference.handle;
head += sizeof(void *);
break;
default:
/* Should never get here */
break;
}
break;
case ACPI_TYPE_PACKAGE:
/* TBD: handle nested packages... */
default:
/* Should never get here */
break;
}
}
return AE_OK;
}
EXPORT_SYMBOL(acpi_extract_package);
acpi_status
acpi_evaluate_integer(acpi_handle handle,
acpi_string pathname,
struct acpi_object_list *arguments, unsigned long long *data)
{
acpi_status status = AE_OK;
union acpi_object element;
struct acpi_buffer buffer = { 0, NULL };
if (!data)
return AE_BAD_PARAMETER;
buffer.length = sizeof(union acpi_object);
buffer.pointer = &element;
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status)) {
acpi_util_eval_error(handle, pathname, status);
return status;
}
if (element.type != ACPI_TYPE_INTEGER) {
acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
return AE_BAD_DATA;
}
*data = element.integer.value;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
return AE_OK;
}
EXPORT_SYMBOL(acpi_evaluate_integer);
acpi_status
acpi_evaluate_reference(acpi_handle handle,
acpi_string pathname,
struct acpi_object_list *arguments,
struct acpi_handle_list *list)
{
acpi_status status = AE_OK;
union acpi_object *package = NULL;
union acpi_object *element = NULL;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
u32 i = 0;
if (!list) {
return AE_BAD_PARAMETER;
}
/* Evaluate object. */
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status))
goto end;
package = buffer.pointer;
if ((buffer.length == 0) || !package) {
status = AE_BAD_DATA;
acpi_util_eval_error(handle, pathname, status);
goto end;
}
if (package->type != ACPI_TYPE_PACKAGE) {
status = AE_BAD_DATA;
acpi_util_eval_error(handle, pathname, status);
goto end;
}
if (!package->package.count) {
status = AE_BAD_DATA;
acpi_util_eval_error(handle, pathname, status);
goto end;
}
if (package->package.count > ACPI_MAX_HANDLES) {
return AE_NO_MEMORY;
}
list->count = package->package.count;
/* Extract package data. */
for (i = 0; i < list->count; i++) {
element = &(package->package.elements[i]);
if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
status = AE_BAD_DATA;
acpi_util_eval_error(handle, pathname, status);
break;
}
if (!element->reference.handle) {
status = AE_NULL_ENTRY;
acpi_util_eval_error(handle, pathname, status);
break;
}
/* Get the acpi_handle. */
list->handles[i] = element->reference.handle;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found reference [%p]\n",
list->handles[i]));
}
end:
if (ACPI_FAILURE(status)) {
list->count = 0;
//kfree(list->handles);
}
kfree(buffer.pointer);
return status;
}
EXPORT_SYMBOL(acpi_evaluate_reference);
acpi_status
acpi_get_physical_device_location(acpi_handle handle, struct acpi_pld_info **pld)
{
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *output;
status = acpi_evaluate_object(handle, "_PLD", NULL, &buffer);
if (ACPI_FAILURE(status))
return status;
output = buffer.pointer;
if (!output || output->type != ACPI_TYPE_PACKAGE
|| !output->package.count
|| output->package.elements[0].type != ACPI_TYPE_BUFFER
|| output->package.elements[0].buffer.length < ACPI_PLD_REV1_BUFFER_SIZE) {
status = AE_TYPE;
goto out;
}
status = acpi_decode_pld_buffer(
output->package.elements[0].buffer.pointer,
output->package.elements[0].buffer.length,
pld);
out:
kfree(buffer.pointer);
return status;
}
EXPORT_SYMBOL(acpi_get_physical_device_location);
/**
* acpi_evaluate_ost: Evaluate _OST for hotplug operations
* @handle: ACPI device handle
* @source_event: source event code
* @status_code: status code
* @status_buf: optional detailed information (NULL if none)
*
* Evaluate _OST for hotplug operations. All ACPI hotplug handlers
* must call this function when evaluating _OST for hotplug operations.
* When the platform does not support _OST, this function has no effect.
*/
acpi_status
acpi_evaluate_ost(acpi_handle handle, u32 source_event, u32 status_code,
struct acpi_buffer *status_buf)
{
union acpi_object params[3] = {
{.type = ACPI_TYPE_INTEGER,},
{.type = ACPI_TYPE_INTEGER,},
{.type = ACPI_TYPE_BUFFER,}
};
struct acpi_object_list arg_list = {3, params};
params[0].integer.value = source_event;
params[1].integer.value = status_code;
if (status_buf != NULL) {
params[2].buffer.pointer = status_buf->pointer;
params[2].buffer.length = status_buf->length;
} else {
params[2].buffer.pointer = NULL;
params[2].buffer.length = 0;
}
return acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
}
EXPORT_SYMBOL(acpi_evaluate_ost);
/**
* acpi_handle_path: Return the object path of handle
*
* Caller must free the returned buffer
*/
static char *acpi_handle_path(acpi_handle handle)
{
struct acpi_buffer buffer = {
.length = ACPI_ALLOCATE_BUFFER,
.pointer = NULL
};
if (in_interrupt() ||
acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer) != AE_OK)
return NULL;
return buffer.pointer;
}
/**
* acpi_handle_printk: Print message with ACPI prefix and object path
*
* This function is called through acpi_handle_<level> macros and prints
* a message with ACPI prefix and object path. This function acquires
* the global namespace mutex to obtain an object path. In interrupt
* context, it shows the object path as <n/a>.
*/
void
acpi_handle_printk(const char *level, acpi_handle handle, const char *fmt, ...)
{
struct va_format vaf;
va_list args;
const char *path;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
path = acpi_handle_path(handle);
printk("%sACPI: %s: %pV", level, path ? path : "<n/a>" , &vaf);
va_end(args);
kfree(path);
}
EXPORT_SYMBOL(acpi_handle_printk);
#if defined(CONFIG_DYNAMIC_DEBUG)
/**
* __acpi_handle_debug: pr_debug with ACPI prefix and object path
*
* This function is called through acpi_handle_debug macro and debug
* prints a message with ACPI prefix and object path. This function
* acquires the global namespace mutex to obtain an object path. In
* interrupt context, it shows the object path as <n/a>.
*/
void
__acpi_handle_debug(struct _ddebug *descriptor, acpi_handle handle,
const char *fmt, ...)
{
struct va_format vaf;
va_list args;
const char *path;
va_start(args, fmt);
vaf.fmt = fmt;
vaf.va = &args;
path = acpi_handle_path(handle);
__dynamic_pr_debug(descriptor, "ACPI: %s: %pV", path ? path : "<n/a>", &vaf);
va_end(args);
kfree(path);
}
EXPORT_SYMBOL(__acpi_handle_debug);
#endif
/**
* acpi_has_method: Check whether @handle has a method named @name
* @handle: ACPI device handle
* @name: name of object or method
*
* Check whether @handle has a method named @name.
*/
bool acpi_has_method(acpi_handle handle, char *name)
{
acpi_handle tmp;
return ACPI_SUCCESS(acpi_get_handle(handle, name, &tmp));
}
EXPORT_SYMBOL(acpi_has_method);
acpi_status acpi_execute_simple_method(acpi_handle handle, char *method,
u64 arg)
{
union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
struct acpi_object_list arg_list = { .count = 1, .pointer = &obj, };
obj.integer.value = arg;
return acpi_evaluate_object(handle, method, &arg_list, NULL);
}
EXPORT_SYMBOL(acpi_execute_simple_method);
/**
* acpi_evaluate_ej0: Evaluate _EJ0 method for hotplug operations
* @handle: ACPI device handle
*
* Evaluate device's _EJ0 method for hotplug operations.
*/
acpi_status acpi_evaluate_ej0(acpi_handle handle)
{
acpi_status status;
status = acpi_execute_simple_method(handle, "_EJ0", 1);
if (status == AE_NOT_FOUND)
acpi_handle_warn(handle, "No _EJ0 support for device\n");
else if (ACPI_FAILURE(status))
acpi_handle_warn(handle, "Eject failed (0x%x)\n", status);
return status;
}
/**
* acpi_evaluate_lck: Evaluate _LCK method to lock/unlock device
* @handle: ACPI device handle
* @lock: lock device if non-zero, otherwise unlock device
*
* Evaluate device's _LCK method if present to lock/unlock device
*/
acpi_status acpi_evaluate_lck(acpi_handle handle, int lock)
{
acpi_status status;
status = acpi_execute_simple_method(handle, "_LCK", !!lock);
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
if (lock)
acpi_handle_warn(handle,
"Locking device failed (0x%x)\n", status);
else
acpi_handle_warn(handle,
"Unlocking device failed (0x%x)\n", status);
}
return status;
}
/**
* acpi_evaluate_dsm - evaluate device's _DSM method
* @handle: ACPI device handle
* @uuid: UUID of requested functions, should be 16 bytes
* @rev: revision number of requested function
* @func: requested function number
* @argv4: the function specific parameter
*
* Evaluate device's _DSM method with specified UUID, revision id and
* function number. Caller needs to free the returned object.
*
* Though ACPI defines the fourth parameter for _DSM should be a package,
* some old BIOSes do expect a buffer or an integer etc.
*/
union acpi_object *
acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid, int rev, int func,
union acpi_object *argv4)
{
acpi_status ret;
struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object params[4];
struct acpi_object_list input = {
.count = 4,
.pointer = params,
};
params[0].type = ACPI_TYPE_BUFFER;
params[0].buffer.length = 16;
params[0].buffer.pointer = (char *)uuid;
params[1].type = ACPI_TYPE_INTEGER;
params[1].integer.value = rev;
params[2].type = ACPI_TYPE_INTEGER;
params[2].integer.value = func;
if (argv4) {
params[3] = *argv4;
} else {
params[3].type = ACPI_TYPE_PACKAGE;
params[3].package.count = 0;
params[3].package.elements = NULL;
}
ret = acpi_evaluate_object(handle, "_DSM", &input, &buf);
if (ACPI_SUCCESS(ret))
return (union acpi_object *)buf.pointer;
if (ret != AE_NOT_FOUND)
acpi_handle_warn(handle,
"failed to evaluate _DSM (0x%x)\n", ret);
return NULL;
}
EXPORT_SYMBOL(acpi_evaluate_dsm);
/**
* acpi_check_dsm - check if _DSM method supports requested functions.
* @handle: ACPI device handle
* @uuid: UUID of requested functions, should be 16 bytes at least
* @rev: revision number of requested functions
* @funcs: bitmap of requested functions
*
* Evaluate device's _DSM method to check whether it supports requested
* functions. Currently only support 64 functions at maximum, should be
* enough for now.
*/
bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs)
{
int i;
u64 mask = 0;
union acpi_object *obj;
if (funcs == 0)
return false;
obj = acpi_evaluate_dsm(handle, uuid, rev, 0, NULL);
if (!obj)
return false;
/* For compatibility, old BIOSes may return an integer */
if (obj->type == ACPI_TYPE_INTEGER)
mask = obj->integer.value;
else if (obj->type == ACPI_TYPE_BUFFER)
for (i = 0; i < obj->buffer.length && i < 8; i++)
mask |= (((u8)obj->buffer.pointer[i]) << (i * 8));
ACPI_FREE(obj);
/*
* Bit 0 indicates whether there's support for any functions other than
* function 0 for the specified UUID and revision.
*/
if ((mask & 0x1) && (mask & funcs) == funcs)
return true;
return false;
}
EXPORT_SYMBOL(acpi_check_dsm);
/*
* acpi_backlight= handling, this is done here rather then in video_detect.c
* because __setup cannot be used in modules.
*/
char acpi_video_backlight_string[16];
EXPORT_SYMBOL(acpi_video_backlight_string);
static int __init acpi_backlight(char *str)
{
strlcpy(acpi_video_backlight_string, str,
sizeof(acpi_video_backlight_string));
return 1;
}
__setup("acpi_backlight=", acpi_backlight);