/******************************************************************************
*
* Module Name: exfield - ACPI AML (p-code) execution - field manipulation
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2005, R. Byron Moore
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*/
#include <acpi/acpi.h>
#include <acpi/acdispat.h>
#include <acpi/acinterp.h>
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME ("exfield")
/*******************************************************************************
*
* FUNCTION: acpi_ex_read_data_from_field
*
* PARAMETERS: walk_state - Current execution state
* obj_desc - The named field
* ret_buffer_desc - Where the return data object is stored
*
* RETURN: Status
*
* DESCRIPTION: Read from a named field. Returns either an Integer or a
* Buffer, depending on the size of the field.
*
******************************************************************************/
acpi_status
acpi_ex_read_data_from_field (
struct acpi_walk_state *walk_state,
union acpi_operand_object *obj_desc,
union acpi_operand_object **ret_buffer_desc)
{
acpi_status status;
union acpi_operand_object *buffer_desc;
acpi_size length;
void *buffer;
u8 locked;
ACPI_FUNCTION_TRACE_PTR ("ex_read_data_from_field", obj_desc);
/* Parameter validation */
if (!obj_desc) {
return_ACPI_STATUS (AE_AML_NO_OPERAND);
}
if (!ret_buffer_desc) {
return_ACPI_STATUS (AE_BAD_PARAMETER);
}
if (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
/*
* If the buffer_field arguments have not been previously evaluated,
* evaluate them now and save the results.
*/
if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
status = acpi_ds_get_buffer_field_arguments (obj_desc);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
}
}
}
else if ((ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_LOCAL_REGION_FIELD) &&
(obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_SMBUS)) {
/*
* This is an SMBus read. We must create a buffer to hold the data
* and directly access the region handler.
*/
buffer_desc = acpi_ut_create_buffer_object (ACPI_SMBUS_BUFFER_SIZE);
if (!buffer_desc) {
return_ACPI_STATUS (AE_NO_MEMORY);
}
/* Lock entire transaction if requested */
locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
/*
* Perform the read.
* Note: Smbus protocol value is passed in upper 16-bits of Function
*/
status = acpi_ex_access_region (obj_desc, 0,
ACPI_CAST_PTR (acpi_integer, buffer_desc->buffer.pointer),
ACPI_READ | (obj_desc->field.attribute << 16));
acpi_ex_release_global_lock (locked);
goto exit;
}
/*
* Allocate a buffer for the contents of the field.
*
* If the field is larger than the size of an acpi_integer, create
* a BUFFER to hold it. Otherwise, use an INTEGER. This allows
* the use of arithmetic operators on the returned value if the
* field size is equal or smaller than an Integer.
*
* Note: Field.length is in bits.
*/
length = (acpi_size) ACPI_ROUND_BITS_UP_TO_BYTES (obj_desc->field.bit_length);
if (length > acpi_gbl_integer_byte_width) {
/* Field is too large for an Integer, create a Buffer instead */
buffer_desc = acpi_ut_create_buffer_object (length);
if (!buffer_desc) {
return_ACPI_STATUS (AE_NO_MEMORY);
}
buffer = buffer_desc->buffer.pointer;
}
else {
/* Field will fit within an Integer (normal case) */
buffer_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
if (!buffer_desc) {
return_ACPI_STATUS (AE_NO_MEMORY);
}
length = acpi_gbl_integer_byte_width;
buffer_desc->integer.value = 0;
buffer = &buffer_desc->integer.value;
}
ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
"field_read [TO]: Obj %p, Type %X, Buf %p, byte_len %X\n",
obj_desc, ACPI_GET_OBJECT_TYPE (obj_desc), buffer, (u32) length));
ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
"field_read [FROM]: bit_len %X, bit_off %X, byte_off %X\n",
obj_desc->common_field.bit_length,
obj_desc->common_field.start_field_bit_offset,
obj_desc->common_field.base_byte_offset));
/* Lock entire transaction if requested */
locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
/* Read from the field */
status = acpi_ex_extract_from_field (obj_desc, buffer, (u32) length);
acpi_ex_release_global_lock (locked);
exit:
if (ACPI_FAILURE (status)) {
acpi_ut_remove_reference (buffer_desc);
}
else {
*ret_buffer_desc = buffer_desc;
}
return_ACPI_STATUS (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_write_data_to_field
*
* PARAMETERS: source_desc - Contains data to write
* obj_desc - The named field
* result_desc - Where the return value is returned, if any
*
* RETURN: Status
*
* DESCRIPTION: Write to a named field
*
******************************************************************************/
acpi_status
acpi_ex_write_data_to_field (
union acpi_operand_object *source_desc,
union acpi_operand_object *obj_desc,
union acpi_operand_object **result_desc)
{
acpi_status status;
u32 length;
u32 required_length;
void *buffer;
void *new_buffer;
u8 locked;
union acpi_operand_object *buffer_desc;
ACPI_FUNCTION_TRACE_PTR ("ex_write_data_to_field", obj_desc);
/* Parameter validation */
if (!source_desc || !obj_desc) {
return_ACPI_STATUS (AE_AML_NO_OPERAND);
}
if (ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_BUFFER_FIELD) {
/*
* If the buffer_field arguments have not been previously evaluated,
* evaluate them now and save the results.
*/
if (!(obj_desc->common.flags & AOPOBJ_DATA_VALID)) {
status = acpi_ds_get_buffer_field_arguments (obj_desc);
if (ACPI_FAILURE (status)) {
return_ACPI_STATUS (status);
}
}
}
else if ((ACPI_GET_OBJECT_TYPE (obj_desc) == ACPI_TYPE_LOCAL_REGION_FIELD) &&
(obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_SMBUS)) {
/*
* This is an SMBus write. We will bypass the entire field mechanism
* and handoff the buffer directly to the handler.
*
* Source must be a buffer of sufficient size (ACPI_SMBUS_BUFFER_SIZE).
*/
if (ACPI_GET_OBJECT_TYPE (source_desc) != ACPI_TYPE_BUFFER) {
ACPI_REPORT_ERROR (("SMBus write requires Buffer, found type %s\n",
acpi_ut_get_object_type_name (source_desc)));
return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
}
if (source_desc->buffer.length < ACPI_SMBUS_BUFFER_SIZE) {
ACPI_REPORT_ERROR ((
"SMBus write requires Buffer of length %X, found length %X\n",
ACPI_SMBUS_BUFFER_SIZE, source_desc->buffer.length));
return_ACPI_STATUS (AE_AML_BUFFER_LIMIT);
}
buffer_desc = acpi_ut_create_buffer_object (ACPI_SMBUS_BUFFER_SIZE);
if (!buffer_desc) {
return_ACPI_STATUS (AE_NO_MEMORY);
}
buffer = buffer_desc->buffer.pointer;
ACPI_MEMCPY (buffer, source_desc->buffer.pointer,
ACPI_SMBUS_BUFFER_SIZE);
/* Lock entire transaction if requested */
locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
/*
* Perform the write (returns status and perhaps data in the
* same buffer)
* Note: SMBus protocol type is passed in upper 16-bits of Function.
*/
status = acpi_ex_access_region (obj_desc, 0,
(acpi_integer *) buffer,
ACPI_WRITE | (obj_desc->field.attribute << 16));
acpi_ex_release_global_lock (locked);
*result_desc = buffer_desc;
return_ACPI_STATUS (status);
}
/* Get a pointer to the data to be written */
switch (ACPI_GET_OBJECT_TYPE (source_desc)) {
case ACPI_TYPE_INTEGER:
buffer = &source_desc->integer.value;
length = sizeof (source_desc->integer.value);
break;
case ACPI_TYPE_BUFFER:
buffer = source_desc->buffer.pointer;
length = source_desc->buffer.length;
break;
case ACPI_TYPE_STRING:
buffer = source_desc->string.pointer;
length = source_desc->string.length;
break;
default:
return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
}
/*
* We must have a buffer that is at least as long as the field
* we are writing to. This is because individual fields are
* indivisible and partial writes are not supported -- as per
* the ACPI specification.
*/
new_buffer = NULL;
required_length = ACPI_ROUND_BITS_UP_TO_BYTES (
obj_desc->common_field.bit_length);
if (length < required_length) {
/* We need to create a new buffer */
new_buffer = ACPI_MEM_CALLOCATE (required_length);
if (!new_buffer) {
return_ACPI_STATUS (AE_NO_MEMORY);
}
/*
* Copy the original data to the new buffer, starting
* at Byte zero. All unused (upper) bytes of the
* buffer will be 0.
*/
ACPI_MEMCPY ((char *) new_buffer, (char *) buffer, length);
buffer = new_buffer;
length = required_length;
}
ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
"field_write [FROM]: Obj %p (%s:%X), Buf %p, byte_len %X\n",
source_desc, acpi_ut_get_type_name (ACPI_GET_OBJECT_TYPE (source_desc)),
ACPI_GET_OBJECT_TYPE (source_desc), buffer, length));
ACPI_DEBUG_PRINT ((ACPI_DB_BFIELD,
"field_write [TO]: Obj %p (%s:%X), bit_len %X, bit_off %X, byte_off %X\n",
obj_desc, acpi_ut_get_type_name (ACPI_GET_OBJECT_TYPE (obj_desc)),
ACPI_GET_OBJECT_TYPE (obj_desc),
obj_desc->common_field.bit_length,
obj_desc->common_field.start_field_bit_offset,
obj_desc->common_field.base_byte_offset));
/* Lock entire transaction if requested */
locked = acpi_ex_acquire_global_lock (obj_desc->common_field.field_flags);
/* Write to the field */
status = acpi_ex_insert_into_field (obj_desc, buffer, length);
acpi_ex_release_global_lock (locked);
/* Free temporary buffer if we used one */
if (new_buffer) {
ACPI_MEM_FREE (new_buffer);
}
return_ACPI_STATUS (status);
}
