HidP_GetUsageValue function (hidpi.h)

04/30/2018
2 minutes to read

The HidP_GetUsageValue routine extracts the data associated with a HID control value that matches the selection criteria in a HID report.

Syntax

NTSTATUS HidP_GetUsageValue(
  HIDP_REPORT_TYPE     ReportType,
  USAGE                UsagePage,
  USHORT               LinkCollection,
  USAGE                Usage,
  PULONG               UsageValue,
  PHIDP_PREPARSED_DATA PreparsedData,
  PCHAR                Report,
  ULONG                ReportLength
);

Parameters

ReportType

[in] Specifies a HIDP_REPORT_TYPE enumerator value that identifies the report type.

UsagePage

[in] Specifies the value's usage page.

LinkCollection

[in] Specifies the link collection that contains the value. If LinkCollection is nonzero, the routine only searches for the usage in this link collection; otherwise, if LinkCollection is zero, the routine searches for the usage in the top-level collection associated with PreparsedData.

Usage

[in] Specifies the usage of the value.

UsageValue

[out] Pointer to a buffer in which the routine returns the value data.

PreparsedData

[in] Pointer to a top-level collection's preparsed data.

Report

[in] Pointer to a report that contains values.

ReportLength

[in] Specifies the length, in bytes, of the report located at Report.

Return value

HidP_GetUsageValue returns one of the following status values:

Return code	Description
HIDP_STATUS_SUCCESS	The routine successfully returned the value data.
HIDP_INVALID_REPORT_LENGTH	The report length is not valid.
HIDP_INVALID_REPORT_TYPE	The specified report type is not valid.
HIDP_STATUS_INCOMPATIBLE_REPORT_ID	The collection contains a value on the specified usage page in a report of the specified type, but there are no such usages in the specified report.
HIDP_STATUS_INVALID_PREPARSED_DATA	The preparsed data is not valid.
HIDP_STATUS_USAGE_NOT_FOUND	The collection does not contain a value on the specified usage page in any report of the specified report type.

Remarks

HidP_GetUsageValue does not sign or scale the value. To extract a signed value, use HidP_GetScaledUsageValue. To manually assign the sign bit, the position of the sign bit can be determined from the information in a value's HIDP_VALUE_CAPS structure.

HidP_GetUsageValue is designed to extract a usage value for a usage whose report count is 1. If the specified usage has a report count greater than 1, the usage is part of a usage value array. HidP_GetUsageValue only returns the first data item in a usage value array. To extract all data items in a usage value array, use HidP_GetUsageValueArray.

For more information, see HID Collections.

Requirements


Minimum supported client	Available in Windows 2000 and later versions of Windows.
Target Platform	Universal
Header	hidpi.h (include Hidpi.h)
Library	Hidparse.lib
IRQL	<= DISPATCH_LEVEL