Linux-2.6.12-rc2

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / acpi / executer / exconvrt.c

/******************************************************************************
 *
 * Module Name: exconvrt - Object conversion routines
 *
 *****************************************************************************/

/*
 * 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/acinterp.h>
#include <acpi/amlcode.h>


#define _COMPONENT          ACPI_EXECUTER
         ACPI_MODULE_NAME    ("exconvrt")


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_to_integer
 *
 * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
 *                                Integer, Buffer, or String
 *              result_desc     - Where the new Integer object is returned
 *              Flags           - Used for string conversion
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an ACPI Object to an integer.
 *
 ******************************************************************************/

acpi_status
acpi_ex_convert_to_integer (
        union acpi_operand_object       *obj_desc,
        union acpi_operand_object       **result_desc,
        u32                             flags)
{
        union acpi_operand_object       *return_desc;
        u8                              *pointer;
        acpi_integer                    result;
        u32                             i;
        u32                             count;
        acpi_status                     status;


        ACPI_FUNCTION_TRACE_PTR ("ex_convert_to_integer", obj_desc);


        switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
        case ACPI_TYPE_INTEGER:

                /* No conversion necessary */

                *result_desc = obj_desc;
                return_ACPI_STATUS (AE_OK);

        case ACPI_TYPE_BUFFER:
        case ACPI_TYPE_STRING:

                /* Note: Takes advantage of common buffer/string fields */

                pointer = obj_desc->buffer.pointer;
                count   = obj_desc->buffer.length;
                break;

        default:
                return_ACPI_STATUS (AE_TYPE);
        }

        /*
         * Convert the buffer/string to an integer.  Note that both buffers and
         * strings are treated as raw data - we don't convert ascii to hex for
         * strings.
         *
         * There are two terminating conditions for the loop:
         * 1) The size of an integer has been reached, or
         * 2) The end of the buffer or string has been reached
         */
        result = 0;

        /*
         * String conversion is different than Buffer conversion
         */
        switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
        case ACPI_TYPE_STRING:

                /*
                 * Convert string to an integer - for most cases, the string must be
                 * hexadecimal as per the ACPI specification.  The only exception (as
                 * of ACPI 3.0) is that the to_integer() operator allows both decimal
                 * and hexadecimal strings (hex prefixed with "0x").
                 */
                status = acpi_ut_strtoul64 ((char *) pointer, flags, &result);
                if (ACPI_FAILURE (status)) {
                        return_ACPI_STATUS (status);
                }
                break;


        case ACPI_TYPE_BUFFER:

                /* Check for zero-length buffer */

                if (!count) {
                        return_ACPI_STATUS (AE_AML_BUFFER_LIMIT);
                }

                /* Transfer no more than an integer's worth of data */

                if (count > acpi_gbl_integer_byte_width) {
                        count = acpi_gbl_integer_byte_width;
                }

                /*
                 * Convert buffer to an integer - we simply grab enough raw data
                 * from the buffer to fill an integer
                 */
                for (i = 0; i < count; i++) {
                        /*
                         * Get next byte and shift it into the Result.
                         * Little endian is used, meaning that the first byte of the buffer
                         * is the LSB of the integer
                         */
                        result |= (((acpi_integer) pointer[i]) << (i * 8));
                }
                break;


        default:
                /* No other types can get here */
                break;
        }

        /*
         * Create a new integer
         */
        return_desc = acpi_ut_create_internal_object (ACPI_TYPE_INTEGER);
        if (!return_desc) {
                return_ACPI_STATUS (AE_NO_MEMORY);
        }

        /* Save the Result */

        return_desc->integer.value = result;
        acpi_ex_truncate_for32bit_table (return_desc);
        *result_desc = return_desc;
        return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_to_buffer
 *
 * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
 *                                Integer, Buffer, or String
 *              result_desc     - Where the new buffer object is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an ACPI Object to a Buffer
 *
 ******************************************************************************/

acpi_status
acpi_ex_convert_to_buffer (
        union acpi_operand_object       *obj_desc,
        union acpi_operand_object       **result_desc)
{
        union acpi_operand_object       *return_desc;
        u8                              *new_buf;


        ACPI_FUNCTION_TRACE_PTR ("ex_convert_to_buffer", obj_desc);


        switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
        case ACPI_TYPE_BUFFER:

                /* No conversion necessary */

                *result_desc = obj_desc;
                return_ACPI_STATUS (AE_OK);


        case ACPI_TYPE_INTEGER:

                /*
                 * Create a new Buffer object.
                 * Need enough space for one integer
                 */
                return_desc = acpi_ut_create_buffer_object (acpi_gbl_integer_byte_width);
                if (!return_desc) {
                        return_ACPI_STATUS (AE_NO_MEMORY);
                }

                /* Copy the integer to the buffer, LSB first */

                new_buf = return_desc->buffer.pointer;
                ACPI_MEMCPY (new_buf,
                                  &obj_desc->integer.value,
                                  acpi_gbl_integer_byte_width);
                break;


        case ACPI_TYPE_STRING:

                /*
                 * Create a new Buffer object
                 * Size will be the string length
                 *
                 * NOTE: Add one to the string length to include the null terminator.
                 * The ACPI spec is unclear on this subject, but there is existing
                 * ASL/AML code that depends on the null being transferred to the new
                 * buffer.
                 */
                return_desc = acpi_ut_create_buffer_object ((acpi_size) obj_desc->string.length + 1);
                if (!return_desc) {
                        return_ACPI_STATUS (AE_NO_MEMORY);
                }

                /* Copy the string to the buffer */

                new_buf = return_desc->buffer.pointer;
                ACPI_STRNCPY ((char *) new_buf, (char *) obj_desc->string.pointer,
                        obj_desc->string.length);
                break;


        default:
                return_ACPI_STATUS (AE_TYPE);
        }

        /* Mark buffer initialized */

        return_desc->common.flags |= AOPOBJ_DATA_VALID;
        *result_desc = return_desc;
        return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_to_ascii
 *
 * PARAMETERS:  Integer         - Value to be converted
 *              Base            - ACPI_STRING_DECIMAL or ACPI_STRING_HEX
 *              String          - Where the string is returned
 *              data_width      - Size of data item to be converted, in bytes
 *
 * RETURN:      Actual string length
 *
 * DESCRIPTION: Convert an ACPI Integer to a hex or decimal string
 *
 ******************************************************************************/

u32
acpi_ex_convert_to_ascii (
        acpi_integer                    integer,
        u16                             base,
        u8                              *string,
        u8                              data_width)
{
        acpi_integer                    digit;
        acpi_native_uint                i;
        acpi_native_uint                j;
        acpi_native_uint                k = 0;
        acpi_native_uint                hex_length;
        acpi_native_uint                decimal_length;
        u32                             remainder;
        u8                              supress_zeros;


        ACPI_FUNCTION_ENTRY ();


        switch (base) {
        case 10:

                /* Setup max length for the decimal number */

                switch (data_width) {
                case 1:
                        decimal_length = ACPI_MAX8_DECIMAL_DIGITS;
                        break;

                case 4:
                        decimal_length = ACPI_MAX32_DECIMAL_DIGITS;
                        break;

                case 8:
                default:
                        decimal_length = ACPI_MAX64_DECIMAL_DIGITS;
                        break;
                }

                supress_zeros = TRUE;    /* No leading zeros */
                remainder = 0;

                for (i = decimal_length; i > 0; i--) {
                        /* Divide by nth factor of 10 */

                        digit = integer;
                        for (j = 0; j < i; j++) {
                                (void) acpi_ut_short_divide (digit, 10, &digit, &remainder);
                        }

                        /* Handle leading zeros */

                        if (remainder != 0) {
                                supress_zeros = FALSE;
                        }

                        if (!supress_zeros) {
                                string[k] = (u8) (ACPI_ASCII_ZERO + remainder);
                                k++;
                        }
                }
                break;

        case 16:

                hex_length = ACPI_MUL_2 (data_width); /* 2 ascii hex chars per data byte */

                for (i = 0, j = (hex_length-1); i < hex_length; i++, j--) {
                        /* Get one hex digit, most significant digits first */

                        string[k] = (u8) acpi_ut_hex_to_ascii_char (integer, ACPI_MUL_4 (j));
                        k++;
                }
                break;

        default:
                return (0);
        }

        /*
         * Since leading zeros are supressed, we must check for the case where
         * the integer equals 0
         *
         * Finally, null terminate the string and return the length
         */
        if (!k) {
                string [0] = ACPI_ASCII_ZERO;
                k = 1;
        }

        string [k] = 0;
        return ((u32) k);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_to_string
 *
 * PARAMETERS:  obj_desc        - Object to be converted.  Must be an
 *                                Integer, Buffer, or String
 *              result_desc     - Where the string object is returned
 *              Type            - String flags (base and conversion type)
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an ACPI Object to a string
 *
 ******************************************************************************/

acpi_status
acpi_ex_convert_to_string (
        union acpi_operand_object       *obj_desc,
        union acpi_operand_object       **result_desc,
        u32                             type)
{
        union acpi_operand_object       *return_desc;
        u8                              *new_buf;
        u32                             i;
        u32                             string_length = 0;
        u16                             base = 16;
        u8                              separator = ',';


        ACPI_FUNCTION_TRACE_PTR ("ex_convert_to_string", obj_desc);


        switch (ACPI_GET_OBJECT_TYPE (obj_desc)) {
        case ACPI_TYPE_STRING:

                /* No conversion necessary */

                *result_desc = obj_desc;
                return_ACPI_STATUS (AE_OK);


        case ACPI_TYPE_INTEGER:

                switch (type) {
                case ACPI_EXPLICIT_CONVERT_DECIMAL:

                        /* Make room for maximum decimal number */

                        string_length = ACPI_MAX_DECIMAL_DIGITS;
                        base = 10;
                        break;

                default:

                        /* Two hex string characters for each integer byte */

                        string_length = ACPI_MUL_2 (acpi_gbl_integer_byte_width);
                        break;
                }

                /*
                 * Create a new String
                 * Need enough space for one ASCII integer (plus null terminator)
                 */
                return_desc = acpi_ut_create_string_object ((acpi_size) string_length);
                if (!return_desc) {
                        return_ACPI_STATUS (AE_NO_MEMORY);
                }

                new_buf = return_desc->buffer.pointer;

                /* Convert integer to string */

                string_length = acpi_ex_convert_to_ascii (obj_desc->integer.value, base,
                                   new_buf, acpi_gbl_integer_byte_width);

                /* Null terminate at the correct place */

                return_desc->string.length = string_length;
                new_buf [string_length] = 0;
                break;


        case ACPI_TYPE_BUFFER:

                /* Setup string length, base, and separator */

                switch (type) {
                case ACPI_EXPLICIT_CONVERT_DECIMAL: /* Used by to_decimal_string operator */
                        /*
                         * From ACPI: "If Data is a buffer, it is converted to a string of
                         * decimal values separated by commas."
                         */
                        base = 10;

                        /*
                         * Calculate the final string length.  Individual string values
                         * are variable length (include separator for each)
                         */
                        for (i = 0; i < obj_desc->buffer.length; i++) {
                                if (obj_desc->buffer.pointer[i] >= 100) {
                                        string_length += 4;
                                }
                                else if (obj_desc->buffer.pointer[i] >= 10) {
                                        string_length += 3;
                                }
                                else {
                                        string_length += 2;
                                }
                        }
                        break;

                case ACPI_IMPLICIT_CONVERT_HEX:
                        /*
                         * From the ACPI spec:
                         *"The entire contents of the buffer are converted to a string of
                         * two-character hexadecimal numbers, each separated by a space."
                         */
                        separator = ' ';
                        string_length = (obj_desc->buffer.length * 3);
                        break;

                case ACPI_EXPLICIT_CONVERT_HEX:     /* Used by to_hex_string operator */
                        /*
                         * From ACPI: "If Data is a buffer, it is converted to a string of
                         * hexadecimal values separated by commas."
                         */
                        string_length = (obj_desc->buffer.length * 3);
                        break;

                default:
                        return_ACPI_STATUS (AE_BAD_PARAMETER);
                }

                /*
                 * Perform the conversion.
                 * (-1 because of extra separator included in string_length from above)
                 */
                string_length--;
                if (string_length > ACPI_MAX_STRING_CONVERSION) /* ACPI limit */ {
                        return_ACPI_STATUS (AE_AML_STRING_LIMIT);
                }

                /*
                 * Create a new string object and string buffer
                 */
                return_desc = acpi_ut_create_string_object ((acpi_size) string_length);
                if (!return_desc) {
                        return_ACPI_STATUS (AE_NO_MEMORY);
                }

                new_buf = return_desc->buffer.pointer;

                /*
                 * Convert buffer bytes to hex or decimal values
                 * (separated by commas or spaces)
                 */
                for (i = 0; i < obj_desc->buffer.length; i++) {
                        new_buf += acpi_ex_convert_to_ascii (
                                         (acpi_integer) obj_desc->buffer.pointer[i], base,
                                         new_buf, 1);
                        *new_buf++ = separator; /* each separated by a comma or space */
                }

                /* Null terminate the string (overwrites final comma/space from above) */

                new_buf--;
                *new_buf = 0;
                break;

        default:
                return_ACPI_STATUS (AE_TYPE);
        }

        *result_desc = return_desc;
        return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_convert_to_target_type
 *
 * PARAMETERS:  destination_type    - Current type of the destination
 *              source_desc         - Source object to be converted.
 *              result_desc         - Where the converted object is returned
 *              walk_state          - Current method state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Implements "implicit conversion" rules for storing an object.
 *
 ******************************************************************************/

acpi_status
acpi_ex_convert_to_target_type (
        acpi_object_type                destination_type,
        union acpi_operand_object       *source_desc,
        union acpi_operand_object       **result_desc,
        struct acpi_walk_state          *walk_state)
{
        acpi_status                     status = AE_OK;


        ACPI_FUNCTION_TRACE ("ex_convert_to_target_type");


        /* Default behavior */

        *result_desc = source_desc;

        /*
         * If required by the target,
         * perform implicit conversion on the source before we store it.
         */
        switch (GET_CURRENT_ARG_TYPE (walk_state->op_info->runtime_args)) {
        case ARGI_SIMPLE_TARGET:
        case ARGI_FIXED_TARGET:
        case ARGI_INTEGER_REF:      /* Handles Increment, Decrement cases */

                switch (destination_type) {
                case ACPI_TYPE_LOCAL_REGION_FIELD:
                        /*
                         * Named field can always handle conversions
                         */
                        break;

                default:
                        /* No conversion allowed for these types */

                        if (destination_type != ACPI_GET_OBJECT_TYPE (source_desc)) {
                                ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                                        "Explicit operator, will store (%s) over existing type (%s)\n",
                                        acpi_ut_get_object_type_name (source_desc),
                                        acpi_ut_get_type_name (destination_type)));
                                status = AE_TYPE;
                        }
                }
                break;


        case ARGI_TARGETREF:

                switch (destination_type) {
                case ACPI_TYPE_INTEGER:
                case ACPI_TYPE_BUFFER_FIELD:
                case ACPI_TYPE_LOCAL_BANK_FIELD:
                case ACPI_TYPE_LOCAL_INDEX_FIELD:
                        /*
                         * These types require an Integer operand.  We can convert
                         * a Buffer or a String to an Integer if necessary.
                         */
                        status = acpi_ex_convert_to_integer (source_desc, result_desc,
                                         16);
                        break;


                case ACPI_TYPE_STRING:

                        /*
                         * The operand must be a String.  We can convert an
                         * Integer or Buffer if necessary
                         */
                        status = acpi_ex_convert_to_string (source_desc, result_desc,
                                         ACPI_IMPLICIT_CONVERT_HEX);
                        break;


                case ACPI_TYPE_BUFFER:

                        /*
                         * The operand must be a Buffer.  We can convert an
                         * Integer or String if necessary
                         */
                        status = acpi_ex_convert_to_buffer (source_desc, result_desc);
                        break;


                default:
                        ACPI_REPORT_ERROR (("Bad destination type during conversion: %X\n",
                                destination_type));
                        status = AE_AML_INTERNAL;
                        break;
                }
                break;


        case ARGI_REFERENCE:
                /*
                 * create_xxxx_field cases - we are storing the field object into the name
                 */
                break;


        default:
                ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
                        "Unknown Target type ID 0x%X Op %s dest_type %s\n",
                        GET_CURRENT_ARG_TYPE (walk_state->op_info->runtime_args),
                        walk_state->op_info->name, acpi_ut_get_type_name (destination_type)));

                ACPI_REPORT_ERROR (("Bad Target Type (ARGI): %X\n",
                        GET_CURRENT_ARG_TYPE (walk_state->op_info->runtime_args)))
                status = AE_AML_INTERNAL;
        }

        /*
         * Source-to-Target conversion semantics:
         *
         * If conversion to the target type cannot be performed, then simply
         * overwrite the target with the new object and type.
         */
        if (status == AE_TYPE) {
                status = AE_OK;
        }

        return_ACPI_STATUS (status);
}