initial commit with v2.6.9

[linux-2.6.9-moxart.git] / drivers / acpi / utilities / utmisc.c

/*******************************************************************************
 *
 * Module Name: utmisc - common utility procedures
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2004, 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/acnamesp.h>


#define _COMPONENT          ACPI_UTILITIES
         ACPI_MODULE_NAME    ("utmisc")


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_print_string
 *
 * PARAMETERS:  String          - Null terminated ASCII string
 *
 * RETURN:      None
 *
 * DESCRIPTION: Dump an ASCII string with support for ACPI-defined escape
 *              sequences.
 *
 ******************************************************************************/

void
acpi_ut_print_string (
        char                            *string,
        u8                              max_length)
{
        u32                             i;


        if (!string) {
                acpi_os_printf ("<\"NULL STRING PTR\">");
                return;
        }

        acpi_os_printf ("\"");
        for (i = 0; string[i] && (i < max_length); i++) {
                /* Escape sequences */

                switch (string[i]) {
                case 0x07:
                        acpi_os_printf ("\\a");      /* BELL */
                        break;

                case 0x08:
                        acpi_os_printf ("\\b");     /* BACKSPACE */
                        break;

                case 0x0C:
                        acpi_os_printf ("\\f");     /* FORMFEED */
                        break;

                case 0x0A:
                        acpi_os_printf ("\\n");     /* LINEFEED */
                        break;

                case 0x0D:
                        acpi_os_printf ("\\r");     /* CARRIAGE RETURN*/
                        break;

                case 0x09:
                        acpi_os_printf ("\\t");     /* HORIZONTAL TAB */
                        break;

                case 0x0B:
                        acpi_os_printf ("\\v");     /* VERTICAL TAB */
                        break;

                case '\'':                      /* Single Quote */
                case '\"':                      /* Double Quote */
                case '\\':                      /* Backslash */
                        acpi_os_printf ("\\%c", (int) string[i]);
                        break;

                default:

                        /* Check for printable character or hex escape */

                        if (ACPI_IS_PRINT (string[i]))
                        {
                                /* This is a normal character */

                                acpi_os_printf ("%c", (int) string[i]);
                        }
                        else
                        {
                                /* All others will be Hex escapes */

                                acpi_os_printf ("\\x%2.2X", (s32) string[i]);
                        }
                        break;
                }
        }
        acpi_os_printf ("\"");

        if (i == max_length && string[i]) {
                acpi_os_printf ("...");
        }
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_dword_byte_swap
 *
 * PARAMETERS:  Value           - Value to be converted
 *
 * DESCRIPTION: Convert a 32-bit value to big-endian (swap the bytes)
 *
 ******************************************************************************/

u32
acpi_ut_dword_byte_swap (
        u32                             value)
{
        union {
                u32                         value;
                u8                          bytes[4];
        } out;

        union {
                u32                         value;
                u8                          bytes[4];
        } in;


        ACPI_FUNCTION_ENTRY ();


        in.value = value;

        out.bytes[0] = in.bytes[3];
        out.bytes[1] = in.bytes[2];
        out.bytes[2] = in.bytes[1];
        out.bytes[3] = in.bytes[0];

        return (out.value);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_set_integer_width
 *
 * PARAMETERS:  Revision            From DSDT header
 *
 * RETURN:      None
 *
 * DESCRIPTION: Set the global integer bit width based upon the revision
 *              of the DSDT.  For Revision 1 and 0, Integers are 32 bits.
 *              For Revision 2 and above, Integers are 64 bits.  Yes, this
 *              makes a difference.
 *
 ******************************************************************************/

void
acpi_ut_set_integer_width (
        u8                              revision)
{

        if (revision <= 1) {
                acpi_gbl_integer_bit_width = 32;
                acpi_gbl_integer_nybble_width = 8;
                acpi_gbl_integer_byte_width = 4;
        }
        else {
                acpi_gbl_integer_bit_width = 64;
                acpi_gbl_integer_nybble_width = 16;
                acpi_gbl_integer_byte_width = 8;
        }
}


#ifdef ACPI_DEBUG_OUTPUT
/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_display_init_pathname
 *
 * PARAMETERS:  obj_handle          - Handle whose pathname will be displayed
 *              Path                - Additional path string to be appended.
 *                                      (NULL if no extra path)
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: Display full pathname of an object, DEBUG ONLY
 *
 ******************************************************************************/

void
acpi_ut_display_init_pathname (
        u8                              type,
        struct acpi_namespace_node      *obj_handle,
        char                            *path)
{
        acpi_status                     status;
        struct acpi_buffer              buffer;


        ACPI_FUNCTION_ENTRY ();


        /* Only print the path if the appropriate debug level is enabled */

        if (!(acpi_dbg_level & ACPI_LV_INIT_NAMES)) {
                return;
        }

        /* Get the full pathname to the node */

        buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
        status = acpi_ns_handle_to_pathname (obj_handle, &buffer);
        if (ACPI_FAILURE (status)) {
                return;
        }

        /* Print what we're doing */

        switch (type) {
        case ACPI_TYPE_METHOD:
                acpi_os_printf ("Executing  ");
                break;

        default:
                acpi_os_printf ("Initializing ");
                break;
        }

        /* Print the object type and pathname */

        acpi_os_printf ("%-12s %s", acpi_ut_get_type_name (type), (char *) buffer.pointer);

        /* Extra path is used to append names like _STA, _INI, etc. */

        if (path) {
                acpi_os_printf (".%s", path);
        }
        acpi_os_printf ("\n");

        ACPI_MEM_FREE (buffer.pointer);
}
#endif


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_valid_acpi_name
 *
 * PARAMETERS:  Character           - The character to be examined
 *
 * RETURN:      1 if Character may appear in a name, else 0
 *
 * DESCRIPTION: Check for a valid ACPI name.  Each character must be one of:
 *              1) Upper case alpha
 *              2) numeric
 *              3) underscore
 *
 ******************************************************************************/

u8
acpi_ut_valid_acpi_name (
        u32                             name)
{
        char                            *name_ptr = (char *) &name;
        char                            character;
        acpi_native_uint                i;


        ACPI_FUNCTION_ENTRY ();


        for (i = 0; i < ACPI_NAME_SIZE; i++) {
                character = *name_ptr;
                name_ptr++;

                if (!((character == '_') ||
                          (character >= 'A' && character <= 'Z') ||
                          (character >= '0' && character <= '9'))) {
                        return (FALSE);
                }
        }

        return (TRUE);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_valid_acpi_character
 *
 * PARAMETERS:  Character           - The character to be examined
 *
 * RETURN:      1 if Character may appear in a name, else 0
 *
 * DESCRIPTION: Check for a printable character
 *
 ******************************************************************************/

u8
acpi_ut_valid_acpi_character (
        char                            character)
{

        ACPI_FUNCTION_ENTRY ();

        return ((u8)   ((character == '_') ||
                           (character >= 'A' && character <= 'Z') ||
                           (character >= '0' && character <= '9')));
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_strtoul64
 *
 * PARAMETERS:  String          - Null terminated string
 *              Terminater      - Where a pointer to the terminating byte is returned
 *              Base            - Radix of the string
 *
 * RETURN:      Converted value
 *
 * DESCRIPTION: Convert a string into an unsigned value.
 *
 ******************************************************************************/
#define NEGATIVE    1
#define POSITIVE    0

acpi_status
acpi_ut_strtoul64 (
        char                            *string,
        u32                             base,
        acpi_integer                    *ret_integer)
{
        u32                             index;
        acpi_integer                    return_value = 0;
        acpi_status                     status = AE_OK;
        acpi_integer                    dividend;
        acpi_integer                    quotient;


        *ret_integer = 0;

        switch (base) {
        case 0:
        case 8:
        case 10:
        case 16:
                break;

        default:
                /*
                 * The specified Base parameter is not in the domain of
                 * this function:
                 */
                return (AE_BAD_PARAMETER);
        }

        /*
         * skip over any white space in the buffer:
         */
        while (ACPI_IS_SPACE (*string) || *string == '\t') {
                ++string;
        }

        /*
         * If the input parameter Base is zero, then we need to
         * determine if it is octal, decimal, or hexadecimal:
         */
        if (base == 0) {
                if (*string == '0') {
                        if (ACPI_TOLOWER (*(++string)) == 'x') {
                                base = 16;
                                ++string;
                        }
                        else {
                                base = 8;
                        }
                }
                else {
                        base = 10;
                }
        }

        /*
         * For octal and hexadecimal bases, skip over the leading
         * 0 or 0x, if they are present.
         */
        if (base == 8 && *string == '0') {
                string++;
        }

        if (base == 16 &&
                *string == '0' &&
                ACPI_TOLOWER (*(++string)) == 'x') {
                string++;
        }

        /* Main loop: convert the string to an unsigned long */

        while (*string) {
                if (ACPI_IS_DIGIT (*string)) {
                        index = ((u8) *string) - '0';
                }
                else {
                        index = (u8) ACPI_TOUPPER (*string);
                        if (ACPI_IS_UPPER ((char) index)) {
                                index = index - 'A' + 10;
                        }
                        else {
                                goto error_exit;
                        }
                }

                if (index >= base) {
                        goto error_exit;
                }

                /* Check to see if value is out of range: */

                dividend = ACPI_INTEGER_MAX - (acpi_integer) index;
                (void) acpi_ut_short_divide (&dividend, base, &quotient, NULL);
                if (return_value > quotient) {
                        goto error_exit;
                }

                return_value *= base;
                return_value += index;
                ++string;
        }

        *ret_integer = return_value;
        return (status);


error_exit:
        switch (base) {
        case 8:
                status = AE_BAD_OCTAL_CONSTANT;
                break;

        case 10:
                status = AE_BAD_DECIMAL_CONSTANT;
                break;

        case 16:
                status = AE_BAD_HEX_CONSTANT;
                break;

        default:
                /* Base validated above */
                break;
        }

        return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_strupr
 *
 * PARAMETERS:  src_string      - The source string to convert to
 *
 * RETURN:      src_string
 *
 * DESCRIPTION: Convert string to uppercase
 *
 ******************************************************************************/

char *
acpi_ut_strupr (
        char                            *src_string)
{
        char                            *string;


        ACPI_FUNCTION_ENTRY ();


        /* Walk entire string, uppercasing the letters */

        for (string = src_string; *string; ) {
                *string = (char) ACPI_TOUPPER (*string);
                string++;
        }

        return (src_string);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_mutex_initialize
 *
 * PARAMETERS:  None.
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create the system mutex objects.
 *
 ******************************************************************************/

acpi_status
acpi_ut_mutex_initialize (
        void)
{
        u32                             i;
        acpi_status                     status;


        ACPI_FUNCTION_TRACE ("ut_mutex_initialize");


        /*
         * Create each of the predefined mutex objects
         */
        for (i = 0; i < NUM_MUTEX; i++) {
                status = acpi_ut_create_mutex (i);
                if (ACPI_FAILURE (status)) {
                        return_ACPI_STATUS (status);
                }
        }

        status = acpi_os_create_lock (&acpi_gbl_gpe_lock);
        return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_mutex_terminate
 *
 * PARAMETERS:  None.
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Delete all of the system mutex objects.
 *
 ******************************************************************************/

void
acpi_ut_mutex_terminate (
        void)
{
        u32                             i;


        ACPI_FUNCTION_TRACE ("ut_mutex_terminate");


        /*
         * Delete each predefined mutex object
         */
        for (i = 0; i < NUM_MUTEX; i++) {
                (void) acpi_ut_delete_mutex (i);
        }

        acpi_os_delete_lock (acpi_gbl_gpe_lock);
        return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_mutex
 *
 * PARAMETERS:  mutex_iD        - ID of the mutex to be created
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create a mutex object.
 *
 ******************************************************************************/

acpi_status
acpi_ut_create_mutex (
        acpi_mutex_handle               mutex_id)
{
        acpi_status                     status = AE_OK;


        ACPI_FUNCTION_TRACE_U32 ("ut_create_mutex", mutex_id);


        if (mutex_id > MAX_MUTEX) {
                return_ACPI_STATUS (AE_BAD_PARAMETER);
        }

        if (!acpi_gbl_mutex_info[mutex_id].mutex) {
                status = acpi_os_create_semaphore (1, 1,
                                  &acpi_gbl_mutex_info[mutex_id].mutex);
                acpi_gbl_mutex_info[mutex_id].owner_id = ACPI_MUTEX_NOT_ACQUIRED;
                acpi_gbl_mutex_info[mutex_id].use_count = 0;
        }

        return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_delete_mutex
 *
 * PARAMETERS:  mutex_iD        - ID of the mutex to be deleted
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Delete a mutex object.
 *
 ******************************************************************************/

acpi_status
acpi_ut_delete_mutex (
        acpi_mutex_handle               mutex_id)
{
        acpi_status                     status;


        ACPI_FUNCTION_TRACE_U32 ("ut_delete_mutex", mutex_id);


        if (mutex_id > MAX_MUTEX) {
                return_ACPI_STATUS (AE_BAD_PARAMETER);
        }

        status = acpi_os_delete_semaphore (acpi_gbl_mutex_info[mutex_id].mutex);

        acpi_gbl_mutex_info[mutex_id].mutex = NULL;
        acpi_gbl_mutex_info[mutex_id].owner_id = ACPI_MUTEX_NOT_ACQUIRED;

        return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_acquire_mutex
 *
 * PARAMETERS:  mutex_iD        - ID of the mutex to be acquired
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Acquire a mutex object.
 *
 ******************************************************************************/

acpi_status
acpi_ut_acquire_mutex (
        acpi_mutex_handle               mutex_id)
{
        acpi_status                     status;
        u32                             i;
        u32                             this_thread_id;


        ACPI_FUNCTION_NAME ("ut_acquire_mutex");


        if (mutex_id > MAX_MUTEX) {
                return (AE_BAD_PARAMETER);
        }

        this_thread_id = acpi_os_get_thread_id ();

        /*
         * Deadlock prevention.  Check if this thread owns any mutexes of value
         * greater than or equal to this one.  If so, the thread has violated
         * the mutex ordering rule.  This indicates a coding error somewhere in
         * the ACPI subsystem code.
         */
        for (i = mutex_id; i < MAX_MUTEX; i++) {
                if (acpi_gbl_mutex_info[i].owner_id == this_thread_id) {
                        if (i == mutex_id) {
                                ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
                                                "Mutex [%s] already acquired by this thread [%X]\n",
                                                acpi_ut_get_mutex_name (mutex_id), this_thread_id));

                                return (AE_ALREADY_ACQUIRED);
                        }

                        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
                                        "Invalid acquire order: Thread %X owns [%s], wants [%s]\n",
                                        this_thread_id, acpi_ut_get_mutex_name (i),
                                        acpi_ut_get_mutex_name (mutex_id)));

                        return (AE_ACQUIRE_DEADLOCK);
                }
        }

        ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX,
                         "Thread %X attempting to acquire Mutex [%s]\n",
                         this_thread_id, acpi_ut_get_mutex_name (mutex_id)));

        status = acpi_os_wait_semaphore (acpi_gbl_mutex_info[mutex_id].mutex,
                           1, ACPI_WAIT_FOREVER);
        if (ACPI_SUCCESS (status)) {
                ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Thread %X acquired Mutex [%s]\n",
                                 this_thread_id, acpi_ut_get_mutex_name (mutex_id)));

                acpi_gbl_mutex_info[mutex_id].use_count++;
                acpi_gbl_mutex_info[mutex_id].owner_id = this_thread_id;
        }
        else {
                ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Thread %X could not acquire Mutex [%s] %s\n",
                                 this_thread_id, acpi_ut_get_mutex_name (mutex_id),
                                 acpi_format_exception (status)));
        }

        return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_release_mutex
 *
 * PARAMETERS:  mutex_iD        - ID of the mutex to be released
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Release a mutex object.
 *
 ******************************************************************************/

acpi_status
acpi_ut_release_mutex (
        acpi_mutex_handle               mutex_id)
{
        acpi_status                     status;
        u32                             i;
        u32                             this_thread_id;


        ACPI_FUNCTION_NAME ("ut_release_mutex");


        this_thread_id = acpi_os_get_thread_id ();
        ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX,
                "Thread %X releasing Mutex [%s]\n", this_thread_id,
                acpi_ut_get_mutex_name (mutex_id)));

        if (mutex_id > MAX_MUTEX) {
                return (AE_BAD_PARAMETER);
        }

        /*
         * Mutex must be acquired in order to release it!
         */
        if (acpi_gbl_mutex_info[mutex_id].owner_id == ACPI_MUTEX_NOT_ACQUIRED) {
                ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
                                "Mutex [%s] is not acquired, cannot release\n",
                                acpi_ut_get_mutex_name (mutex_id)));

                return (AE_NOT_ACQUIRED);
        }

        /*
         * Deadlock prevention.  Check if this thread owns any mutexes of value
         * greater than this one.  If so, the thread has violated the mutex
         * ordering rule.  This indicates a coding error somewhere in
         * the ACPI subsystem code.
         */
        for (i = mutex_id; i < MAX_MUTEX; i++) {
                if (acpi_gbl_mutex_info[i].owner_id == this_thread_id) {
                        if (i == mutex_id) {
                                continue;
                        }

                        ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
                                        "Invalid release order: owns [%s], releasing [%s]\n",
                                        acpi_ut_get_mutex_name (i), acpi_ut_get_mutex_name (mutex_id)));

                        return (AE_RELEASE_DEADLOCK);
                }
        }

        /* Mark unlocked FIRST */

        acpi_gbl_mutex_info[mutex_id].owner_id = ACPI_MUTEX_NOT_ACQUIRED;

        status = acpi_os_signal_semaphore (acpi_gbl_mutex_info[mutex_id].mutex, 1);

        if (ACPI_FAILURE (status)) {
                ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Thread %X could not release Mutex [%s] %s\n",
                                 this_thread_id, acpi_ut_get_mutex_name (mutex_id),
                                 acpi_format_exception (status)));
        }
        else {
                ACPI_DEBUG_PRINT ((ACPI_DB_MUTEX, "Thread %X released Mutex [%s]\n",
                                 this_thread_id, acpi_ut_get_mutex_name (mutex_id)));
        }

        return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_update_state_and_push
 *
 * PARAMETERS:  *Object         - Object to be added to the new state
 *              Action          - Increment/Decrement
 *              state_list      - List the state will be added to
 *
 * RETURN:      None
 *
 * DESCRIPTION: Create a new state and push it
 *
 ******************************************************************************/

acpi_status
acpi_ut_create_update_state_and_push (
        union acpi_operand_object       *object,
        u16                             action,
        union acpi_generic_state        **state_list)
{
        union acpi_generic_state         *state;


        ACPI_FUNCTION_ENTRY ();


        /* Ignore null objects; these are expected */

        if (!object) {
                return (AE_OK);
        }

        state = acpi_ut_create_update_state (object, action);
        if (!state) {
                return (AE_NO_MEMORY);
        }

        acpi_ut_push_generic_state (state_list, state);
        return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_pkg_state_and_push
 *
 * PARAMETERS:  *Object         - Object to be added to the new state
 *              Action          - Increment/Decrement
 *              state_list      - List the state will be added to
 *
 * RETURN:      None
 *
 * DESCRIPTION: Create a new state and push it
 *
 ******************************************************************************/

acpi_status
acpi_ut_create_pkg_state_and_push (
        void                            *internal_object,
        void                            *external_object,
        u16                             index,
        union acpi_generic_state        **state_list)
{
        union acpi_generic_state         *state;


        ACPI_FUNCTION_ENTRY ();


        state = acpi_ut_create_pkg_state (internal_object, external_object, index);
        if (!state) {
                return (AE_NO_MEMORY);
        }

        acpi_ut_push_generic_state (state_list, state);
        return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_push_generic_state
 *
 * PARAMETERS:  list_head           - Head of the state stack
 *              State               - State object to push
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Push a state object onto a state stack
 *
 ******************************************************************************/

void
acpi_ut_push_generic_state (
        union acpi_generic_state        **list_head,
        union acpi_generic_state        *state)
{
        ACPI_FUNCTION_TRACE ("ut_push_generic_state");


        /* Push the state object onto the front of the list (stack) */

        state->common.next = *list_head;
        *list_head = state;

        return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_pop_generic_state
 *
 * PARAMETERS:  list_head           - Head of the state stack
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Pop a state object from a state stack
 *
 ******************************************************************************/

union acpi_generic_state *
acpi_ut_pop_generic_state (
        union acpi_generic_state        **list_head)
{
        union acpi_generic_state        *state;


        ACPI_FUNCTION_TRACE ("ut_pop_generic_state");


        /* Remove the state object at the head of the list (stack) */

        state = *list_head;
        if (state) {
                /* Update the list head */

                *list_head = state->common.next;
        }

        return_PTR (state);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_generic_state
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create a generic state object.  Attempt to obtain one from
 *              the global state cache;  If none available, create a new one.
 *
 ******************************************************************************/

union acpi_generic_state *
acpi_ut_create_generic_state (void)
{
        union acpi_generic_state        *state;


        ACPI_FUNCTION_ENTRY ();


        state = acpi_ut_acquire_from_cache (ACPI_MEM_LIST_STATE);

        /* Initialize */

        if (state) {
                state->common.data_type = ACPI_DESC_TYPE_STATE;
        }

        return (state);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_thread_state
 *
 * PARAMETERS:  None
 *
 * RETURN:      Thread State
 *
 * DESCRIPTION: Create a "Thread State" - a flavor of the generic state used
 *              to track per-thread info during method execution
 *
 ******************************************************************************/

struct acpi_thread_state *
acpi_ut_create_thread_state (
        void)
{
        union acpi_generic_state        *state;


        ACPI_FUNCTION_TRACE ("ut_create_thread_state");


        /* Create the generic state object */

        state = acpi_ut_create_generic_state ();
        if (!state) {
                return_PTR (NULL);
        }

        /* Init fields specific to the update struct */

        state->common.data_type = ACPI_DESC_TYPE_STATE_THREAD;
        state->thread.thread_id = acpi_os_get_thread_id ();

        return_PTR ((struct acpi_thread_state *) state);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_update_state
 *
 * PARAMETERS:  Object              - Initial Object to be installed in the
 *                                    state
 *              Action              - Update action to be performed
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create an "Update State" - a flavor of the generic state used
 *              to update reference counts and delete complex objects such
 *              as packages.
 *
 ******************************************************************************/

union acpi_generic_state *
acpi_ut_create_update_state (
        union acpi_operand_object       *object,
        u16                             action)
{
        union acpi_generic_state        *state;


        ACPI_FUNCTION_TRACE_PTR ("ut_create_update_state", object);


        /* Create the generic state object */

        state = acpi_ut_create_generic_state ();
        if (!state) {
                return_PTR (NULL);
        }

        /* Init fields specific to the update struct */

        state->common.data_type = ACPI_DESC_TYPE_STATE_UPDATE;
        state->update.object = object;
        state->update.value  = action;

        return_PTR (state);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_pkg_state
 *
 * PARAMETERS:  Object              - Initial Object to be installed in the
 *                                    state
 *              Action              - Update action to be performed
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create a "Package State"
 *
 ******************************************************************************/

union acpi_generic_state *
acpi_ut_create_pkg_state (
        void                            *internal_object,
        void                            *external_object,
        u16                             index)
{
        union acpi_generic_state        *state;


        ACPI_FUNCTION_TRACE_PTR ("ut_create_pkg_state", internal_object);


        /* Create the generic state object */

        state = acpi_ut_create_generic_state ();
        if (!state) {
                return_PTR (NULL);
        }

        /* Init fields specific to the update struct */

        state->common.data_type = ACPI_DESC_TYPE_STATE_PACKAGE;
        state->pkg.source_object = (union acpi_operand_object *) internal_object;
        state->pkg.dest_object  = external_object;
        state->pkg.index        = index;
        state->pkg.num_packages = 1;

        return_PTR (state);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_create_control_state
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Create a "Control State" - a flavor of the generic state used
 *              to support nested IF/WHILE constructs in the AML.
 *
 ******************************************************************************/

union acpi_generic_state *
acpi_ut_create_control_state (
        void)
{
        union acpi_generic_state        *state;


        ACPI_FUNCTION_TRACE ("ut_create_control_state");


        /* Create the generic state object */

        state = acpi_ut_create_generic_state ();
        if (!state) {
                return_PTR (NULL);
        }

        /* Init fields specific to the control struct */

        state->common.data_type = ACPI_DESC_TYPE_STATE_CONTROL;
        state->common.state     = ACPI_CONTROL_CONDITIONAL_EXECUTING;

        return_PTR (state);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_delete_generic_state
 *
 * PARAMETERS:  State               - The state object to be deleted
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Put a state object back into the global state cache.  The object
 *              is not actually freed at this time.
 *
 ******************************************************************************/

void
acpi_ut_delete_generic_state (
        union acpi_generic_state        *state)
{
        ACPI_FUNCTION_TRACE ("ut_delete_generic_state");


        acpi_ut_release_to_cache (ACPI_MEM_LIST_STATE, state);
        return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_delete_generic_state_cache
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Purge the global state object cache.  Used during subsystem
 *              termination.
 *
 ******************************************************************************/

void
acpi_ut_delete_generic_state_cache (
        void)
{
        ACPI_FUNCTION_TRACE ("ut_delete_generic_state_cache");


        acpi_ut_delete_generic_cache (ACPI_MEM_LIST_STATE);
        return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_walk_package_tree
 *
 * PARAMETERS:  obj_desc        - The Package object on which to resolve refs
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Walk through a package
 *
 ******************************************************************************/

acpi_status
acpi_ut_walk_package_tree (
        union acpi_operand_object       *source_object,
        void                            *target_object,
        acpi_pkg_callback               walk_callback,
        void                            *context)
{
        acpi_status                     status = AE_OK;
        union acpi_generic_state        *state_list = NULL;
        union acpi_generic_state        *state;
        u32                             this_index;
        union acpi_operand_object       *this_source_obj;


        ACPI_FUNCTION_TRACE ("ut_walk_package_tree");


        state = acpi_ut_create_pkg_state (source_object, target_object, 0);
        if (!state) {
                return_ACPI_STATUS (AE_NO_MEMORY);
        }

        while (state) {
                /* Get one element of the package */

                this_index    = state->pkg.index;
                this_source_obj = (union acpi_operand_object *)
                                  state->pkg.source_object->package.elements[this_index];

                /*
                 * Check for:
                 * 1) An uninitialized package element.  It is completely
                 *    legal to declare a package and leave it uninitialized
                 * 2) Not an internal object - can be a namespace node instead
                 * 3) Any type other than a package.  Packages are handled in else
                 *    case below.
                 */
                if ((!this_source_obj) ||
                        (ACPI_GET_DESCRIPTOR_TYPE (this_source_obj) != ACPI_DESC_TYPE_OPERAND) ||
                        (ACPI_GET_OBJECT_TYPE (this_source_obj) != ACPI_TYPE_PACKAGE)) {
                        status = walk_callback (ACPI_COPY_TYPE_SIMPLE, this_source_obj,
                                         state, context);
                        if (ACPI_FAILURE (status)) {
                                return_ACPI_STATUS (status);
                        }

                        state->pkg.index++;
                        while (state->pkg.index >= state->pkg.source_object->package.count) {
                                /*
                                 * We've handled all of the objects at this level,  This means
                                 * that we have just completed a package.  That package may
                                 * have contained one or more packages itself.
                                 *
                                 * Delete this state and pop the previous state (package).
                                 */
                                acpi_ut_delete_generic_state (state);
                                state = acpi_ut_pop_generic_state (&state_list);

                                /* Finished when there are no more states */

                                if (!state) {
                                        /*
                                         * We have handled all of the objects in the top level
                                         * package just add the length of the package objects
                                         * and exit
                                         */
                                        return_ACPI_STATUS (AE_OK);
                                }

                                /*
                                 * Go back up a level and move the index past the just
                                 * completed package object.
                                 */
                                state->pkg.index++;
                        }
                }
                else {
                        /* This is a subobject of type package */

                        status = walk_callback (ACPI_COPY_TYPE_PACKAGE, this_source_obj,
                                          state, context);
                        if (ACPI_FAILURE (status)) {
                                return_ACPI_STATUS (status);
                        }

                        /*
                         * Push the current state and create a new one
                         * The callback above returned a new target package object.
                         */
                        acpi_ut_push_generic_state (&state_list, state);
                        state = acpi_ut_create_pkg_state (this_source_obj,
                                           state->pkg.this_target_obj, 0);
                        if (!state) {
                                return_ACPI_STATUS (AE_NO_MEMORY);
                        }
                }
        }

        /* We should never get here */

        return_ACPI_STATUS (AE_AML_INTERNAL);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_generate_checksum
 *
 * PARAMETERS:  Buffer          - Buffer to be scanned
 *              Length          - number of bytes to examine
 *
 * RETURN:      checksum
 *
 * DESCRIPTION: Generate a checksum on a raw buffer
 *
 ******************************************************************************/

u8
acpi_ut_generate_checksum (
        u8                              *buffer,
        u32                             length)
{
        u32                             i;
        signed char                     sum = 0;


        for (i = 0; i < length; i++) {
                sum = (signed char) (sum + buffer[i]);
        }

        return ((u8) (0 - sum));
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_get_resource_end_tag
 *
 * PARAMETERS:  obj_desc        - The resource template buffer object
 *
 * RETURN:      Pointer to the end tag
 *
 * DESCRIPTION: Find the END_TAG resource descriptor in a resource template
 *
 ******************************************************************************/


u8 *
acpi_ut_get_resource_end_tag (
        union acpi_operand_object       *obj_desc)
{
        u8                              buffer_byte;
        u8                              *buffer;
        u8                              *end_buffer;


        buffer    = obj_desc->buffer.pointer;
        end_buffer = buffer + obj_desc->buffer.length;

        while (buffer < end_buffer) {
                buffer_byte = *buffer;
                if (buffer_byte & ACPI_RDESC_TYPE_MASK) {
                        /* Large Descriptor - Length is next 2 bytes */

                        buffer += ((*(buffer+1) | (*(buffer+2) << 8)) + 3);
                }
                else {
                        /* Small Descriptor.  End Tag will be found here */

                        if ((buffer_byte & ACPI_RDESC_SMALL_MASK) == ACPI_RDESC_TYPE_END_TAG) {
                                /* Found the end tag descriptor, all done. */

                                return (buffer);
                        }

                        /* Length is in the header */

                        buffer += ((buffer_byte & 0x07) + 1);
                }
        }

        /* End tag not found */

        return (NULL);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_report_error
 *
 * PARAMETERS:  module_name         - Caller's module name (for error output)
 *              line_number         - Caller's line number (for error output)
 *              component_id        - Caller's component ID (for error output)
 *              Message             - Error message to use on failure
 *
 * RETURN:      None
 *
 * DESCRIPTION: Print error message
 *
 ******************************************************************************/

void
acpi_ut_report_error (
        char                            *module_name,
        u32                             line_number,
        u32                             component_id)
{


        acpi_os_printf ("%8s-%04d: *** Error: ", module_name, line_number);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_report_warning
 *
 * PARAMETERS:  module_name         - Caller's module name (for error output)
 *              line_number         - Caller's line number (for error output)
 *              component_id        - Caller's component ID (for error output)
 *              Message             - Error message to use on failure
 *
 * RETURN:      None
 *
 * DESCRIPTION: Print warning message
 *
 ******************************************************************************/

void
acpi_ut_report_warning (
        char                            *module_name,
        u32                             line_number,
        u32                             component_id)
{

        acpi_os_printf ("%8s-%04d: *** Warning: ", module_name, line_number);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_report_info
 *
 * PARAMETERS:  module_name         - Caller's module name (for error output)
 *              line_number         - Caller's line number (for error output)
 *              component_id        - Caller's component ID (for error output)
 *              Message             - Error message to use on failure
 *
 * RETURN:      None
 *
 * DESCRIPTION: Print information message
 *
 ******************************************************************************/

void
acpi_ut_report_info (
        char                            *module_name,
        u32                             line_number,
        u32                             component_id)
{

        acpi_os_printf ("%8s-%04d: *** Info: ", module_name, line_number);
}