// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: nsxfname - Public interfaces to the ACPI subsystem
* ACPI Namespace oriented interfaces
*
* Copyright (C) 2000 - 2025, Intel Corp.
*
*****************************************************************************/
#define EXPORT_ACPI_INTERFACES
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "acparser.h"
#include "amlcode.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME(
"nsxfname")
/* Local prototypes */
static char *acpi_ns_copy_device_id(
struct acpi_pnp_device_id *dest,
struct acpi_pnp_device_id *source,
char *string_area);
/******************************************************************************
*
* FUNCTION: acpi_get_handle
*
* PARAMETERS: parent - Object to search under (search scope).
* pathname - Pointer to an asciiz string containing the
* name
* ret_handle - Where the return handle is returned
*
* RETURN: Status
*
* DESCRIPTION: This routine will search for a caller specified name in the
* name space. The caller can restrict the search region by
* specifying a non NULL parent. The parent value is itself a
* namespace handle.
*
******************************************************************************/
acpi_status
acpi_get_handle(acpi_handle parent,
const char *pathname, acpi_handle *ret_handle)
{
acpi_status status;
struct acpi_namespace_node *node = NULL;
struct acpi_namespace_node *prefix_node = NULL;
ACPI_FUNCTION_ENTRY();
/* Parameter Validation */
if (!ret_handle || !pathname) {
return (AE_BAD_PARAMETER);
}
/* Convert a parent handle to a prefix node */
if (parent) {
prefix_node = acpi_ns_validate_handle(parent);
if (!prefix_node) {
return (AE_BAD_PARAMETER);
}
}
/*
* Valid cases are:
* 1) Fully qualified pathname
* 2) Parent + Relative pathname
*
* Error for <null Parent + relative path>
*/
if (ACPI_IS_ROOT_PREFIX(pathname[0])) {
/* Pathname is fully qualified (starts with '\') */
/* Special case for root-only, since we can't search for it */
if (!strcmp(pathname, ACPI_NS_ROOT_PATH)) {
*ret_handle =
ACPI_CAST_PTR(acpi_handle, acpi_gbl_root_node);
return (AE_OK);
}
}
else if (!prefix_node) {
/* Relative path with null prefix is disallowed */
return (AE_BAD_PARAMETER);
}
/* Find the Node and convert to a handle */
status =
acpi_ns_get_node(prefix_node, pathname, ACPI_NS_NO_UPSEARCH, &node);
if (ACPI_SUCCESS(status)) {
*ret_handle = ACPI_CAST_PTR(acpi_handle, node);
}
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_get_handle)
/******************************************************************************
*
* FUNCTION: acpi_get_name
*
* PARAMETERS: handle - Handle to be converted to a pathname
* name_type - Full pathname or single segment
* buffer - Buffer for returned path
*
* RETURN: Pointer to a string containing the fully qualified Name.
*
* DESCRIPTION: This routine returns the fully qualified name associated with
* the Handle parameter. This and the acpi_pathname_to_handle are
* complementary functions.
*
******************************************************************************/
acpi_status
acpi_get_name(acpi_handle handle, u32 name_type,
struct acpi_buffer *buffer)
{
acpi_status status;
/* Parameter validation */
if (name_type > ACPI_NAME_TYPE_MAX) {
return (AE_BAD_PARAMETER);
}
status = acpi_ut_validate_buffer(buffer);
if (ACPI_FAILURE(status)) {
return (status);
}
/*
* Wants the single segment ACPI name.
* Validate handle and convert to a namespace Node
*/
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
if (name_type == ACPI_FULL_PATHNAME ||
name_type == ACPI_FULL_PATHNAME_NO_TRAILING) {
/* Get the full pathname (From the namespace root) */
status = acpi_ns_handle_to_pathname(handle, buffer,
name_type ==
ACPI_FULL_PATHNAME ?
FALSE :
TRUE);
}
else {
/* Get the single name */
status = acpi_ns_handle_to_name(handle, buffer);
}
(
void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_get_name)
/******************************************************************************
*
* FUNCTION: acpi_ns_copy_device_id
*
* PARAMETERS: dest - Pointer to the destination PNP_DEVICE_ID
* source - Pointer to the source PNP_DEVICE_ID
* string_area - Pointer to where to copy the dest string
*
* RETURN: Pointer to the next string area
*
* DESCRIPTION: Copy a single PNP_DEVICE_ID, including the string data.
*
******************************************************************************/
static char *acpi_ns_copy_device_id(
struct acpi_pnp_device_id *dest,
struct acpi_pnp_device_id *source,
char *string_area)
{
/* Create the destination PNP_DEVICE_ID */
dest->string = string_area;
dest->length = source->length;
/* Copy actual string and return a pointer to the next string area */
memcpy(string_area, source->string, source->length);
return (string_area + source->length);
}
/******************************************************************************
*
* FUNCTION: acpi_get_object_info
*
* PARAMETERS: handle - Object Handle
* return_buffer - Where the info is returned
*
* RETURN: Status
*
* DESCRIPTION: Returns information about an object as gleaned from the
* namespace node and possibly by running several standard
* control methods (Such as in the case of a device.)
*
* For Device and Processor objects, run the Device _HID, _UID, _CID,
* _CLS, _ADR, _sx_w, and _sx_d methods.
*
* Note: Allocates the return buffer, must be freed by the caller.
*
* Note: This interface is intended to be used during the initial device
* discovery namespace traversal. Therefore, no complex methods can be
* executed, especially those that access operation regions. Therefore, do
* not add any additional methods that could cause problems in this area.
* Because of this reason support for the following methods has been removed:
* 1) _SUB method was removed (11/2015)
* 2) _STA method was removed (02/2018)
*
******************************************************************************/
acpi_status
acpi_get_object_info(acpi_handle handle,
struct acpi_device_info **return_buffer)
{
struct acpi_namespace_node *node;
struct acpi_device_info *info;
struct acpi_pnp_device_id_list *cid_list = NULL;
struct acpi_pnp_device_id *hid = NULL;
struct acpi_pnp_device_id *uid = NULL;
struct acpi_pnp_device_id *cls = NULL;
char *next_id_string;
acpi_object_type type;
acpi_name name;
u8 param_count = 0;
u16 valid = 0;
u32 info_size;
u32 i;
acpi_status status;
/* Parameter validation */
if (!handle || !return_buffer) {
return (AE_BAD_PARAMETER);
}
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
node = acpi_ns_validate_handle(handle);
if (!node) {
(
void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return (AE_BAD_PARAMETER);
}
/* Get the namespace node data while the namespace is locked */
info_size =
sizeof(
struct acpi_device_info);
type = node->type;
name = node->name.integer;
if (node->type == ACPI_TYPE_METHOD) {
param_count = node->object->method.param_count;
}
status = acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
if ((type == ACPI_TYPE_DEVICE) || (type == ACPI_TYPE_PROCESSOR)) {
/*
* Get extra info for ACPI Device/Processor objects only:
* Run the Device _HID, _UID, _CLS, and _CID methods.
*
* Note: none of these methods are required, so they may or may
* not be present for this device. The Info->Valid bitfield is used
* to indicate which methods were found and run successfully.
*/
/* Execute the Device._HID method */
status = acpi_ut_execute_HID(node, &hid);
if (ACPI_SUCCESS(status)) {
info_size += hid->length;
valid |= ACPI_VALID_HID;
}
/* Execute the Device._UID method */
status = acpi_ut_execute_UID(node, &uid);
if (ACPI_SUCCESS(status)) {
info_size += uid->length;
valid |= ACPI_VALID_UID;
}
/* Execute the Device._CID method */
status = acpi_ut_execute_CID(node, &cid_list);
if (ACPI_SUCCESS(status)) {
/* Add size of CID strings and CID pointer array */
info_size +=
(cid_list->list_size -
sizeof(
struct acpi_pnp_device_id_list));
valid |= ACPI_VALID_CID;
}
/* Execute the Device._CLS method */
status = acpi_ut_execute_CLS(node, &cls);
if (ACPI_SUCCESS(status)) {
info_size += cls->length;
valid |= ACPI_VALID_CLS;
}
}
/*
* Now that we have the variable-length data, we can allocate the
* return buffer
*/
info = ACPI_ALLOCATE_ZEROED(info_size);
if (!info) {
status = AE_NO_MEMORY;
goto cleanup;
}
/* Get the fixed-length data */
if ((type == ACPI_TYPE_DEVICE) || (type == ACPI_TYPE_PROCESSOR)) {
/*
* Get extra info for ACPI Device/Processor objects only:
* Run the _ADR and, sx_w, and _sx_d methods.
*
* Notes: none of these methods are required, so they may or may
* not be present for this device. The Info->Valid bitfield is used
* to indicate which methods were found and run successfully.
*/
/* Execute the Device._ADR method */
status = acpi_ut_evaluate_numeric_object(METHOD_NAME__ADR, node,
&info->address);
if (ACPI_SUCCESS(status)) {
valid |= ACPI_VALID_ADR;
}
/* Execute the Device._sx_w methods */
status = acpi_ut_execute_power_methods(node,
acpi_gbl_lowest_dstate_names,
ACPI_NUM_sx_w_METHODS,
info->lowest_dstates);
if (ACPI_SUCCESS(status)) {
valid |= ACPI_VALID_SXWS;
}
/* Execute the Device._sx_d methods */
status = acpi_ut_execute_power_methods(node,
acpi_gbl_highest_dstate_names,
ACPI_NUM_sx_d_METHODS,
info->highest_dstates);
if (ACPI_SUCCESS(status)) {
valid |= ACPI_VALID_SXDS;
}
}
/*
* Create a pointer to the string area of the return buffer.
* Point to the end of the base struct acpi_device_info structure.
*/
next_id_string = ACPI_CAST_PTR(
char, info->compatible_id_list.ids);
if (cid_list) {
/* Point past the CID PNP_DEVICE_ID array */
next_id_string +=
((acpi_size)cid_list->count *
sizeof(
struct acpi_pnp_device_id));
}
/*
* Copy the HID, UID, and CIDs to the return buffer. The variable-length
* strings are copied to the reserved area at the end of the buffer.
*
* For HID and CID, check if the ID is a PCI Root Bridge.
*/
if (hid) {
next_id_string = acpi_ns_copy_device_id(&info->hardware_id,
hid, next_id_string);
if (acpi_ut_is_pci_root_bridge(hid->string)) {
info->flags |= ACPI_PCI_ROOT_BRIDGE;
}
}
if (uid) {
next_id_string = acpi_ns_copy_device_id(&info->unique_id,
uid, next_id_string);
}
if (cid_list) {
info->compatible_id_list.count = cid_list->count;
info->compatible_id_list.list_size = cid_list->list_size;
/* Copy each CID */
for (i = 0; i < cid_list->count; i++) {
next_id_string =
acpi_ns_copy_device_id(&info->compatible_id_list.
ids[i], &cid_list->ids[i],
next_id_string);
if (acpi_ut_is_pci_root_bridge(cid_list->ids[i].string)) {
info->flags |= ACPI_PCI_ROOT_BRIDGE;
}
}
}
if (cls) {
(
void)acpi_ns_copy_device_id(&info->class_code,
cls, next_id_string);
}
/* Copy the fixed-length data */
info->info_size = info_size;
info->type = type;
info->name = name;
info->param_count = param_count;
info->valid = valid;
*return_buffer = info;
status = AE_OK;
cleanup:
if (hid) {
ACPI_FREE(hid);
}
if (uid) {
ACPI_FREE(uid);
}
if (cid_list) {
ACPI_FREE(cid_list);
}
if (cls) {
ACPI_FREE(cls);
}
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_get_object_info)
/******************************************************************************
*
* FUNCTION: acpi_install_method
*
* PARAMETERS: buffer - An ACPI table containing one control method
*
* RETURN: Status
*
* DESCRIPTION: Install a control method into the namespace. If the method
* name already exists in the namespace, it is overwritten. The
* input buffer must contain a valid DSDT or SSDT containing a
* single control method.
*
******************************************************************************/
acpi_status acpi_install_method(u8 *buffer)
{
struct acpi_table_header *table =
ACPI_CAST_PTR(
struct acpi_table_header, buffer);
u8 *aml_buffer;
u8 *aml_start;
char *path;
struct acpi_namespace_node *node;
union acpi_operand_object *method_obj;
struct acpi_parse_state parser_state;
u32 aml_length;
u16 opcode;
u8 method_flags;
acpi_status status;
/* Parameter validation */
if (!buffer) {
return (AE_BAD_PARAMETER);
}
/* Table must be a DSDT or SSDT */
if (!ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_DSDT) &&
!ACPI_COMPARE_NAMESEG(table->signature, ACPI_SIG_SSDT)) {
return (AE_BAD_HEADER);
}
/* First AML opcode in the table must be a control method */
parser_state.aml = buffer +
sizeof(
struct acpi_table_header);
opcode = acpi_ps_peek_opcode(&parser_state);
if (opcode != AML_METHOD_OP) {
return (AE_BAD_PARAMETER);
}
/* Extract method information from the raw AML */
parser_state.aml += acpi_ps_get_opcode_size(opcode);
parser_state.pkg_end = acpi_ps_get_next_package_end(&parser_state);
path = acpi_ps_get_next_namestring(&parser_state);
method_flags = *parser_state.aml++;
aml_start = parser_state.aml;
aml_length = (u32)ACPI_PTR_DIFF(parser_state.pkg_end, aml_start);
/*
* Allocate resources up-front. We don't want to have to delete a new
* node from the namespace if we cannot allocate memory.
*/
aml_buffer = ACPI_ALLOCATE(aml_length);
if (!aml_buffer) {
return (AE_NO_MEMORY);
}
method_obj = acpi_ut_create_internal_object(ACPI_TYPE_METHOD);
if (!method_obj) {
ACPI_FREE(aml_buffer);
return (AE_NO_MEMORY);
}
/* Lock namespace for acpi_ns_lookup, we may be creating a new node */
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
goto error_exit;
}
/* The lookup either returns an existing node or creates a new one */
status =
acpi_ns_lookup(NULL, path, ACPI_TYPE_METHOD, ACPI_IMODE_LOAD_PASS1,
ACPI_NS_DONT_OPEN_SCOPE | ACPI_NS_ERROR_IF_FOUND,
NULL, &node);
(
void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
/* ns_lookup */
if (status != AE_ALREADY_EXISTS) {
goto error_exit;
}
/* Node existed previously, make sure it is a method node */
if (node->type != ACPI_TYPE_METHOD) {
status = AE_TYPE;
goto error_exit;
}
}
/* Copy the method AML to the local buffer */
memcpy(aml_buffer, aml_start, aml_length);
/* Initialize the method object with the new method's information */
method_obj->method.aml_start = aml_buffer;
method_obj->method.aml_length = aml_length;
method_obj->method.param_count = (u8)
(method_flags & AML_METHOD_ARG_COUNT);
if (method_flags & AML_METHOD_SERIALIZED) {
method_obj->method.info_flags = ACPI_METHOD_SERIALIZED;
method_obj->method.sync_level = (u8)
((method_flags & AML_METHOD_SYNC_LEVEL) >> 4);
}
/*
* Now that it is complete, we can attach the new method object to
* the method Node (detaches/deletes any existing object)
*/
status = acpi_ns_attach_object(node, method_obj, ACPI_TYPE_METHOD);
/*
* Flag indicates AML buffer is dynamic, must be deleted later.
* Must be set only after attach above.
*/
node->flags |= ANOBJ_ALLOCATED_BUFFER;
/* Remove local reference to the method object */
acpi_ut_remove_reference(method_obj);
return (status);
error_exit:
ACPI_FREE(aml_buffer);
ACPI_FREE(method_obj);
return (status);
}
ACPI_EXPORT_SYMBOL(acpi_install_method)
