// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
 *
 * Module Name: nsxfobj - Public interfaces to the ACPI subsystem
 *                         ACPI Object oriented interfaces
 *
 ******************************************************************************/

#define EXPORT_ACPI_INTERFACES

#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "amlcode.h"

#define _COMPONENT          ACPI_NAMESPACE
ACPI_MODULE_NAME("nsxfobj")

/*
 * This table maps the various Attrib protocols to the byte transfer
 * length. Used for the generic serial bus.
 */
#define ACPI_INVALID_PROTOCOL_ID        0x80
#define ACPI_MAX_PROTOCOL_ID            0x0F
const u8 acpi_protocol_lengths[] = {
	ACPI_INVALID_PROTOCOL_ID,	/* 0 - reserved */
	ACPI_INVALID_PROTOCOL_ID,	/* 1 - reserved */
	0x00,			/* 2 - ATTRIB_QUICK */
	ACPI_INVALID_PROTOCOL_ID,	/* 3 - reserved */
	0x01,			/* 4 - ATTRIB_SEND_RECEIVE */
	ACPI_INVALID_PROTOCOL_ID,	/* 5 - reserved */
	0x01,			/* 6 - ATTRIB_BYTE */
	ACPI_INVALID_PROTOCOL_ID,	/* 7 - reserved */
	0x02,			/* 8 - ATTRIB_WORD */
	ACPI_INVALID_PROTOCOL_ID,	/* 9 - reserved */
	0xFF,			/* A - ATTRIB_BLOCK  */
	0xFF,			/* B - ATTRIB_BYTES */
	0x02,			/* C - ATTRIB_PROCESS_CALL */
	0xFF,			/* D - ATTRIB_BLOCK_PROCESS_CALL */
	0xFF,			/* E - ATTRIB_RAW_BYTES */
	0xFF			/* F - ATTRIB_RAW_PROCESS_BYTES */
};

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_serial_access_length
 *
 * PARAMETERS:  accessor_type   - The type of the protocol indicated by region
 *                                field access attributes
 *              access_length   - The access length of the region field
 *
 * RETURN:      Decoded access length
 *
 * DESCRIPTION: This routine returns the length of the generic_serial_bus
 *              protocol bytes
 *
 ******************************************************************************/
u32 acpi_get_serial_access_length(u32 accessor_type, u32 access_length)
{
    if ((accessor_type > ACPI_MAX_PROTOCOL_ID) ||
        (acpi_protocol_lengths[accessor_type] == ACPI_INVALID_PROTOCOL_ID))
    {
        ACPI_ERROR((AE_INFO, "Invalid Field/AccessAs protocol ID: 0x%4.4X",
                    accessor_type));
        return (ACPI_MAX_GSBUS_BUFFER_SIZE);
    }

    return (acpi_protocol_lengths[accessor_type]);
}
ACPI_EXPORT_SYMBOL(acpi_get_serial_access_length);

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_type
 *
 * PARAMETERS:  handle          - Handle of object whose type is desired
 *              ret_type        - Where the type will be placed
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This routine returns the type associated with a particular
 *              handle
 *
 ******************************************************************************/
acpi_status acpi_get_type(acpi_handle handle, acpi_object_type *ret_type)
{
	struct acpi_namespace_node *node;
	acpi_status status;

	/* Parameter Validation */

	if (!ret_type) {
		return (AE_BAD_PARAMETER);
	}

	/* Special case for the predefined Root Node (return type ANY) */

	if (handle == ACPI_ROOT_OBJECT) {
		*ret_type = ACPI_TYPE_ANY;
		return (AE_OK);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* Convert and validate the handle */

	node = acpi_ns_validate_handle(handle);
	if (!node) {
		(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
		return (AE_BAD_PARAMETER);
	}

	*ret_type = node->type;

	status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return (status);
}

ACPI_EXPORT_SYMBOL(acpi_get_type)

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_parent
 *
 * PARAMETERS:  handle          - Handle of object whose parent is desired
 *              ret_handle      - Where the parent handle will be placed
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Returns a handle to the parent of the object represented by
 *              Handle.
 *
 ******************************************************************************/
acpi_status acpi_get_parent(acpi_handle handle, acpi_handle *ret_handle)
{
	struct acpi_namespace_node *node;
	struct acpi_namespace_node *parent_node;
	acpi_status status;

	if (!ret_handle) {
		return (AE_BAD_PARAMETER);
	}

	/* Special case for the predefined Root Node (no parent) */

	if (handle == ACPI_ROOT_OBJECT) {
		return (AE_NULL_ENTRY);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* Convert and validate the handle */

	node = acpi_ns_validate_handle(handle);
	if (!node) {
		status = AE_BAD_PARAMETER;
		goto unlock_and_exit;
	}

	/* Get the parent entry */

	parent_node = node->parent;
	*ret_handle = ACPI_CAST_PTR(acpi_handle, parent_node);

	/* Return exception if parent is null */

	if (!parent_node) {
		status = AE_NULL_ENTRY;
	}

unlock_and_exit:

	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return (status);
}

ACPI_EXPORT_SYMBOL(acpi_get_parent)

/*******************************************************************************
 *
 * FUNCTION:    acpi_get_next_object
 *
 * PARAMETERS:  type            - Type of object to be searched for
 *              parent          - Parent object whose children we are getting
 *              last_child      - Previous child that was found.
 *                                The NEXT child will be returned
 *              ret_handle      - Where handle to the next object is placed
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Return the next peer object within the namespace. If Handle is
 *              valid, Scope is ignored. Otherwise, the first object within
 *              Scope is returned.
 *
 ******************************************************************************/
acpi_status
acpi_get_next_object(acpi_object_type type,
		     acpi_handle parent,
		     acpi_handle child, acpi_handle *ret_handle)
{
	acpi_status status;
	struct acpi_namespace_node *node;
	struct acpi_namespace_node *parent_node = NULL;
	struct acpi_namespace_node *child_node = NULL;

	/* Parameter validation */

	if (type > ACPI_TYPE_EXTERNAL_MAX) {
		return (AE_BAD_PARAMETER);
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return (status);
	}

	/* If null handle, use the parent */

	if (!child) {

		/* Start search at the beginning of the specified scope */

		parent_node = acpi_ns_validate_handle(parent);
		if (!parent_node) {
			status = AE_BAD_PARAMETER;
			goto unlock_and_exit;
		}
	} else {
		/* Non-null handle, ignore the parent */
		/* Convert and validate the handle */

		child_node = acpi_ns_validate_handle(child);
		if (!child_node) {
			status = AE_BAD_PARAMETER;
			goto unlock_and_exit;
		}
	}

	/* Internal function does the real work */

	node = acpi_ns_get_next_node_typed(type, parent_node, child_node);
	if (!node) {
		status = AE_NOT_FOUND;
		goto unlock_and_exit;
	}

	if (ret_handle) {
		*ret_handle = ACPI_CAST_PTR(acpi_handle, node);
	}

unlock_and_exit:

	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return (status);
}

ACPI_EXPORT_SYMBOL(acpi_get_next_object)