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5599fb6935
ACPICA commit 92ec0935f27e217dff0b176fca02c2ec3d782bb5 ACPI_COMPARE_NAME changed to ACPI_COMPARE_NAMESEG This clarifies (1) this is a compare on 4-byte namesegs, not a generic compare. Improves understanding of the code. Link: https://github.com/acpica/acpica/commit/92ec0935 Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Erik Schmauss <erik.schmauss@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
629 lines
19 KiB
C
629 lines
19 KiB
C
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
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/*******************************************************************************
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*
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* Module Name: rsxface - Public interfaces to the resource manager
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*
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******************************************************************************/
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#define EXPORT_ACPI_INTERFACES
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#include <acpi/acpi.h>
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#include "accommon.h"
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#include "acresrc.h"
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#include "acnamesp.h"
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#define _COMPONENT ACPI_RESOURCES
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ACPI_MODULE_NAME("rsxface")
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/* Local macros for 16,32-bit to 64-bit conversion */
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#define ACPI_COPY_FIELD(out, in, field) ((out)->field = (in)->field)
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#define ACPI_COPY_ADDRESS(out, in) \
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ACPI_COPY_FIELD(out, in, resource_type); \
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ACPI_COPY_FIELD(out, in, producer_consumer); \
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ACPI_COPY_FIELD(out, in, decode); \
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ACPI_COPY_FIELD(out, in, min_address_fixed); \
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ACPI_COPY_FIELD(out, in, max_address_fixed); \
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ACPI_COPY_FIELD(out, in, info); \
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ACPI_COPY_FIELD(out, in, address.granularity); \
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ACPI_COPY_FIELD(out, in, address.minimum); \
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ACPI_COPY_FIELD(out, in, address.maximum); \
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ACPI_COPY_FIELD(out, in, address.translation_offset); \
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ACPI_COPY_FIELD(out, in, address.address_length); \
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ACPI_COPY_FIELD(out, in, resource_source);
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/* Local prototypes */
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static acpi_status
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acpi_rs_match_vendor_resource(struct acpi_resource *resource, void *context);
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static acpi_status
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acpi_rs_validate_parameters(acpi_handle device_handle,
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struct acpi_buffer *buffer,
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struct acpi_namespace_node **return_node);
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/*******************************************************************************
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*
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* FUNCTION: acpi_rs_validate_parameters
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*
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* PARAMETERS: device_handle - Handle to a device
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* buffer - Pointer to a data buffer
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* return_node - Pointer to where the device node is returned
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*
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* RETURN: Status
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*
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* DESCRIPTION: Common parameter validation for resource interfaces
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*
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******************************************************************************/
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static acpi_status
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acpi_rs_validate_parameters(acpi_handle device_handle,
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struct acpi_buffer *buffer,
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struct acpi_namespace_node **return_node)
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{
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acpi_status status;
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struct acpi_namespace_node *node;
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ACPI_FUNCTION_TRACE(rs_validate_parameters);
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/*
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* Must have a valid handle to an ACPI device
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*/
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if (!device_handle) {
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return_ACPI_STATUS(AE_BAD_PARAMETER);
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}
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node = acpi_ns_validate_handle(device_handle);
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if (!node) {
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return_ACPI_STATUS(AE_BAD_PARAMETER);
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}
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if (node->type != ACPI_TYPE_DEVICE) {
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return_ACPI_STATUS(AE_TYPE);
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}
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/*
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* Validate the user buffer object
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*
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* if there is a non-zero buffer length we also need a valid pointer in
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* the buffer. If it's a zero buffer length, we'll be returning the
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* needed buffer size (later), so keep going.
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*/
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status = acpi_ut_validate_buffer(buffer);
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if (ACPI_FAILURE(status)) {
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return_ACPI_STATUS(status);
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}
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*return_node = node;
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return_ACPI_STATUS(AE_OK);
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}
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/*******************************************************************************
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*
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* FUNCTION: acpi_get_irq_routing_table
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*
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* PARAMETERS: device_handle - Handle to the Bus device we are querying
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* ret_buffer - Pointer to a buffer to receive the
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* current resources for the device
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*
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* RETURN: Status
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*
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* DESCRIPTION: This function is called to get the IRQ routing table for a
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* specific bus. The caller must first acquire a handle for the
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* desired bus. The routine table is placed in the buffer pointed
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* to by the ret_buffer variable parameter.
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*
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* If the function fails an appropriate status will be returned
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* and the value of ret_buffer is undefined.
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*
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* This function attempts to execute the _PRT method contained in
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* the object indicated by the passed device_handle.
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*
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******************************************************************************/
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acpi_status
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acpi_get_irq_routing_table(acpi_handle device_handle,
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struct acpi_buffer *ret_buffer)
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{
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acpi_status status;
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struct acpi_namespace_node *node;
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ACPI_FUNCTION_TRACE(acpi_get_irq_routing_table);
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/* Validate parameters then dispatch to internal routine */
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status = acpi_rs_validate_parameters(device_handle, ret_buffer, &node);
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if (ACPI_FAILURE(status)) {
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return_ACPI_STATUS(status);
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}
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status = acpi_rs_get_prt_method_data(node, ret_buffer);
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return_ACPI_STATUS(status);
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}
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ACPI_EXPORT_SYMBOL(acpi_get_irq_routing_table)
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/*******************************************************************************
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*
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* FUNCTION: acpi_get_current_resources
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*
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* PARAMETERS: device_handle - Handle to the device object for the
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* device we are querying
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* ret_buffer - Pointer to a buffer to receive the
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* current resources for the device
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*
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* RETURN: Status
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*
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* DESCRIPTION: This function is called to get the current resources for a
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* specific device. The caller must first acquire a handle for
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* the desired device. The resource data is placed in the buffer
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* pointed to by the ret_buffer variable parameter.
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*
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* If the function fails an appropriate status will be returned
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* and the value of ret_buffer is undefined.
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*
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* This function attempts to execute the _CRS method contained in
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* the object indicated by the passed device_handle.
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*
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******************************************************************************/
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acpi_status
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acpi_get_current_resources(acpi_handle device_handle,
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struct acpi_buffer *ret_buffer)
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{
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acpi_status status;
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struct acpi_namespace_node *node;
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ACPI_FUNCTION_TRACE(acpi_get_current_resources);
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/* Validate parameters then dispatch to internal routine */
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status = acpi_rs_validate_parameters(device_handle, ret_buffer, &node);
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if (ACPI_FAILURE(status)) {
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return_ACPI_STATUS(status);
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}
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status = acpi_rs_get_crs_method_data(node, ret_buffer);
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return_ACPI_STATUS(status);
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}
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ACPI_EXPORT_SYMBOL(acpi_get_current_resources)
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/*******************************************************************************
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*
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* FUNCTION: acpi_get_possible_resources
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*
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* PARAMETERS: device_handle - Handle to the device object for the
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* device we are querying
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* ret_buffer - Pointer to a buffer to receive the
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* resources for the device
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*
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* RETURN: Status
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*
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* DESCRIPTION: This function is called to get a list of the possible resources
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* for a specific device. The caller must first acquire a handle
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* for the desired device. The resource data is placed in the
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* buffer pointed to by the ret_buffer variable.
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*
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* If the function fails an appropriate status will be returned
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* and the value of ret_buffer is undefined.
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*
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******************************************************************************/
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acpi_status
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acpi_get_possible_resources(acpi_handle device_handle,
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struct acpi_buffer *ret_buffer)
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{
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acpi_status status;
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struct acpi_namespace_node *node;
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ACPI_FUNCTION_TRACE(acpi_get_possible_resources);
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/* Validate parameters then dispatch to internal routine */
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status = acpi_rs_validate_parameters(device_handle, ret_buffer, &node);
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if (ACPI_FAILURE(status)) {
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return_ACPI_STATUS(status);
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}
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status = acpi_rs_get_prs_method_data(node, ret_buffer);
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return_ACPI_STATUS(status);
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}
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ACPI_EXPORT_SYMBOL(acpi_get_possible_resources)
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/*******************************************************************************
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*
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* FUNCTION: acpi_set_current_resources
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*
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* PARAMETERS: device_handle - Handle to the device object for the
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* device we are setting resources
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* in_buffer - Pointer to a buffer containing the
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* resources to be set for the device
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*
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* RETURN: Status
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*
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* DESCRIPTION: This function is called to set the current resources for a
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* specific device. The caller must first acquire a handle for
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* the desired device. The resource data is passed to the routine
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* the buffer pointed to by the in_buffer variable.
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*
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******************************************************************************/
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acpi_status
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acpi_set_current_resources(acpi_handle device_handle,
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struct acpi_buffer *in_buffer)
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{
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acpi_status status;
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struct acpi_namespace_node *node;
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ACPI_FUNCTION_TRACE(acpi_set_current_resources);
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/* Validate the buffer, don't allow zero length */
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if ((!in_buffer) || (!in_buffer->pointer) || (!in_buffer->length)) {
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return_ACPI_STATUS(AE_BAD_PARAMETER);
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}
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/* Validate parameters then dispatch to internal routine */
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status = acpi_rs_validate_parameters(device_handle, in_buffer, &node);
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if (ACPI_FAILURE(status)) {
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return_ACPI_STATUS(status);
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}
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status = acpi_rs_set_srs_method_data(node, in_buffer);
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return_ACPI_STATUS(status);
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}
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ACPI_EXPORT_SYMBOL(acpi_set_current_resources)
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/*******************************************************************************
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*
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* FUNCTION: acpi_get_event_resources
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*
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* PARAMETERS: device_handle - Handle to the device object for the
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* device we are getting resources
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* in_buffer - Pointer to a buffer containing the
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* resources to be set for the device
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*
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* RETURN: Status
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*
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* DESCRIPTION: This function is called to get the event resources for a
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* specific device. The caller must first acquire a handle for
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* the desired device. The resource data is passed to the routine
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* the buffer pointed to by the in_buffer variable. Uses the
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* _AEI method.
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*
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******************************************************************************/
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acpi_status
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acpi_get_event_resources(acpi_handle device_handle,
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struct acpi_buffer *ret_buffer)
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{
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acpi_status status;
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struct acpi_namespace_node *node;
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ACPI_FUNCTION_TRACE(acpi_get_event_resources);
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/* Validate parameters then dispatch to internal routine */
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status = acpi_rs_validate_parameters(device_handle, ret_buffer, &node);
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if (ACPI_FAILURE(status)) {
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return_ACPI_STATUS(status);
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}
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status = acpi_rs_get_aei_method_data(node, ret_buffer);
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return_ACPI_STATUS(status);
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}
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ACPI_EXPORT_SYMBOL(acpi_get_event_resources)
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/******************************************************************************
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*
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* FUNCTION: acpi_resource_to_address64
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*
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* PARAMETERS: resource - Pointer to a resource
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* out - Pointer to the users's return buffer
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* (a struct acpi_resource_address64)
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*
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* RETURN: Status
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*
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* DESCRIPTION: If the resource is an address16, address32, or address64,
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* copy it to the address64 return buffer. This saves the
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* caller from having to duplicate code for different-sized
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* addresses.
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*
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******************************************************************************/
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acpi_status
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acpi_resource_to_address64(struct acpi_resource *resource,
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struct acpi_resource_address64 *out)
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{
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struct acpi_resource_address16 *address16;
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struct acpi_resource_address32 *address32;
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if (!resource || !out) {
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return (AE_BAD_PARAMETER);
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}
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/* Convert 16 or 32 address descriptor to 64 */
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switch (resource->type) {
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case ACPI_RESOURCE_TYPE_ADDRESS16:
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address16 =
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ACPI_CAST_PTR(struct acpi_resource_address16,
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&resource->data);
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ACPI_COPY_ADDRESS(out, address16);
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break;
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case ACPI_RESOURCE_TYPE_ADDRESS32:
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address32 =
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ACPI_CAST_PTR(struct acpi_resource_address32,
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&resource->data);
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ACPI_COPY_ADDRESS(out, address32);
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break;
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case ACPI_RESOURCE_TYPE_ADDRESS64:
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/* Simple copy for 64 bit source */
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memcpy(out, &resource->data,
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sizeof(struct acpi_resource_address64));
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break;
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default:
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return (AE_BAD_PARAMETER);
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}
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return (AE_OK);
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}
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ACPI_EXPORT_SYMBOL(acpi_resource_to_address64)
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/*******************************************************************************
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*
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* FUNCTION: acpi_get_vendor_resource
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*
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* PARAMETERS: device_handle - Handle for the parent device object
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* name - Method name for the parent resource
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* (METHOD_NAME__CRS or METHOD_NAME__PRS)
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* uuid - Pointer to the UUID to be matched.
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* includes both subtype and 16-byte UUID
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* ret_buffer - Where the vendor resource is returned
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*
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* RETURN: Status
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*
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* DESCRIPTION: Walk a resource template for the specified device to find a
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* vendor-defined resource that matches the supplied UUID and
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* UUID subtype. Returns a struct acpi_resource of type Vendor.
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*
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******************************************************************************/
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acpi_status
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acpi_get_vendor_resource(acpi_handle device_handle,
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char *name,
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struct acpi_vendor_uuid *uuid,
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struct acpi_buffer *ret_buffer)
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{
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struct acpi_vendor_walk_info info;
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acpi_status status;
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/* Other parameters are validated by acpi_walk_resources */
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if (!uuid || !ret_buffer) {
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return (AE_BAD_PARAMETER);
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}
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info.uuid = uuid;
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info.buffer = ret_buffer;
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info.status = AE_NOT_EXIST;
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/* Walk the _CRS or _PRS resource list for this device */
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status =
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acpi_walk_resources(device_handle, name,
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acpi_rs_match_vendor_resource, &info);
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if (ACPI_FAILURE(status)) {
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return (status);
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}
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return (info.status);
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}
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ACPI_EXPORT_SYMBOL(acpi_get_vendor_resource)
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/*******************************************************************************
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*
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* FUNCTION: acpi_rs_match_vendor_resource
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*
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* PARAMETERS: acpi_walk_resource_callback
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*
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* RETURN: Status
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*
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* DESCRIPTION: Match a vendor resource via the ACPI 3.0 UUID
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*
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******************************************************************************/
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static acpi_status
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acpi_rs_match_vendor_resource(struct acpi_resource *resource, void *context)
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{
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struct acpi_vendor_walk_info *info = context;
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struct acpi_resource_vendor_typed *vendor;
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struct acpi_buffer *buffer;
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acpi_status status;
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/* Ignore all descriptors except Vendor */
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if (resource->type != ACPI_RESOURCE_TYPE_VENDOR) {
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return (AE_OK);
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}
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vendor = &resource->data.vendor_typed;
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/*
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* For a valid match, these conditions must hold:
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*
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* 1) Length of descriptor data must be at least as long as a UUID struct
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* 2) The UUID subtypes must match
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* 3) The UUID data must match
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*/
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if ((vendor->byte_length < (ACPI_UUID_LENGTH + 1)) ||
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(vendor->uuid_subtype != info->uuid->subtype) ||
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(memcmp(vendor->uuid, info->uuid->data, ACPI_UUID_LENGTH))) {
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return (AE_OK);
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}
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/* Validate/Allocate/Clear caller buffer */
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buffer = info->buffer;
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status = acpi_ut_initialize_buffer(buffer, resource->length);
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if (ACPI_FAILURE(status)) {
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return (status);
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}
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/* Found the correct resource, copy and return it */
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memcpy(buffer->pointer, resource, resource->length);
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buffer->length = resource->length;
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/* Found the desired descriptor, terminate resource walk */
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info->status = AE_OK;
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return (AE_CTRL_TERMINATE);
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}
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/*******************************************************************************
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*
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* FUNCTION: acpi_walk_resource_buffer
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*
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* PARAMETERS: buffer - Formatted buffer returned by one of the
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* various Get*Resource functions
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* user_function - Called for each resource
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* context - Passed to user_function
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*
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* RETURN: Status
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*
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* DESCRIPTION: Walks the input resource template. The user_function is called
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* once for each resource in the list.
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*
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******************************************************************************/
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acpi_status
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acpi_walk_resource_buffer(struct acpi_buffer *buffer,
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acpi_walk_resource_callback user_function,
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void *context)
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{
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acpi_status status = AE_OK;
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struct acpi_resource *resource;
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struct acpi_resource *resource_end;
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ACPI_FUNCTION_TRACE(acpi_walk_resource_buffer);
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/* Parameter validation */
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if (!buffer || !buffer->pointer || !user_function) {
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return_ACPI_STATUS(AE_BAD_PARAMETER);
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}
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/* Buffer contains the resource list and length */
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resource = ACPI_CAST_PTR(struct acpi_resource, buffer->pointer);
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resource_end =
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ACPI_ADD_PTR(struct acpi_resource, buffer->pointer, buffer->length);
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/* Walk the resource list until the end_tag is found (or buffer end) */
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while (resource < resource_end) {
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/* Sanity check the resource type */
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|
|
if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
|
|
status = AE_AML_INVALID_RESOURCE_TYPE;
|
|
break;
|
|
}
|
|
|
|
/* Sanity check the length. It must not be zero, or we loop forever */
|
|
|
|
if (!resource->length) {
|
|
return_ACPI_STATUS(AE_AML_BAD_RESOURCE_LENGTH);
|
|
}
|
|
|
|
/* Invoke the user function, abort on any error returned */
|
|
|
|
status = user_function(resource, context);
|
|
if (ACPI_FAILURE(status)) {
|
|
if (status == AE_CTRL_TERMINATE) {
|
|
|
|
/* This is an OK termination by the user function */
|
|
|
|
status = AE_OK;
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* end_tag indicates end-of-list */
|
|
|
|
if (resource->type == ACPI_RESOURCE_TYPE_END_TAG) {
|
|
break;
|
|
}
|
|
|
|
/* Get the next resource descriptor */
|
|
|
|
resource = ACPI_NEXT_RESOURCE(resource);
|
|
}
|
|
|
|
return_ACPI_STATUS(status);
|
|
}
|
|
|
|
ACPI_EXPORT_SYMBOL(acpi_walk_resource_buffer)
|
|
|
|
/*******************************************************************************
|
|
*
|
|
* FUNCTION: acpi_walk_resources
|
|
*
|
|
* PARAMETERS: device_handle - Handle to the device object for the
|
|
* device we are querying
|
|
* name - Method name of the resources we want.
|
|
* (METHOD_NAME__CRS, METHOD_NAME__PRS, or
|
|
* METHOD_NAME__AEI or METHOD_NAME__DMA)
|
|
* user_function - Called for each resource
|
|
* context - Passed to user_function
|
|
*
|
|
* RETURN: Status
|
|
*
|
|
* DESCRIPTION: Retrieves the current or possible resource list for the
|
|
* specified device. The user_function is called once for
|
|
* each resource in the list.
|
|
*
|
|
******************************************************************************/
|
|
acpi_status
|
|
acpi_walk_resources(acpi_handle device_handle,
|
|
char *name,
|
|
acpi_walk_resource_callback user_function, void *context)
|
|
{
|
|
acpi_status status;
|
|
struct acpi_buffer buffer;
|
|
|
|
ACPI_FUNCTION_TRACE(acpi_walk_resources);
|
|
|
|
/* Parameter validation */
|
|
|
|
if (!device_handle || !user_function || !name ||
|
|
(!ACPI_COMPARE_NAMESEG(name, METHOD_NAME__CRS) &&
|
|
!ACPI_COMPARE_NAMESEG(name, METHOD_NAME__PRS) &&
|
|
!ACPI_COMPARE_NAMESEG(name, METHOD_NAME__AEI) &&
|
|
!ACPI_COMPARE_NAMESEG(name, METHOD_NAME__DMA))) {
|
|
return_ACPI_STATUS(AE_BAD_PARAMETER);
|
|
}
|
|
|
|
/* Get the _CRS/_PRS/_AEI/_DMA resource list */
|
|
|
|
buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
|
|
status = acpi_rs_get_method_data(device_handle, name, &buffer);
|
|
if (ACPI_FAILURE(status)) {
|
|
return_ACPI_STATUS(status);
|
|
}
|
|
|
|
/* Walk the resource list and cleanup */
|
|
|
|
status = acpi_walk_resource_buffer(&buffer, user_function, context);
|
|
ACPI_FREE(buffer.pointer);
|
|
return_ACPI_STATUS(status);
|
|
}
|
|
|
|
ACPI_EXPORT_SYMBOL(acpi_walk_resources)
|