// hidpi.h
NTSTATUS HidP_GetUsages(
[in] HIDP_REPORT_TYPE ReportType,
[in] USAGE UsagePage,
[in] USHORT LinkCollection,
[out] PUSAGE UsageList,
[in, out] PULONG UsageLength,
[in] PHIDP_PREPARSED_DATA PreparsedData,
[out] PCHAR Report,
[in] ULONG ReportLength
);
View the official Windows Driver Kit DDI referenceNo description available.
The HidP_GetUsages routine returns a list of all the HID control button usages that are on a specified usage page and are set to ON in a HID report.
ReportType [in]Specifies a HIDP_REPORT_TYPE enumerator value that identifies the report type.
UsagePage [in]Specifies the usage page of the button usages. The routine only returns information about buttons on this usage page.
LinkCollection [in]Specifies the link collection of the button usages. If LinkCollection is nonzero, the routine only returns information about the buttons that this link collection contains; otherwise, if LinkCollection is zero, the routine returns information about all the buttons in the top-level collection associated with PreparsedData.
UsageList [out]Pointer to a caller-allocated buffer that the routine uses to return the usages of all buttons that are set to ON and belong to the usage page specified by UsagePage.
UsageLength [in, out]Specifies, on input, the length, in array elements, of the UsageList buffer. Specifies, on output, the number of buttons that are set to ON on the specified usage page.
PreparsedData [in]Pointer to a top-level collection's preparsed data.
Report [out]Pointer to a report.
ReportLength [in]Specifies the length, in bytes, of the report located at Report.
HidP_GetUsages returns one of the following status values:
| Return code | Description |
|---|---|
| HIDP_STATUS_SUCCESS | The routine successfully returned all button usages set to ON. |
| HIDP_STATUS_INVALID_REPORT_LENGTH | The report length is not valid. |
| HIDP_STATUS_INVALID_REPORT_TYPE | The specified report type is not valid. |
| HIDP_STATUS_BUFFER_TOO_SMALL | The UsageList buffer is too small to hold all the usages that are currently set to ON on the specified usage page. |
| HIDP_STATUS_INCOMPATIBLE_REPORT_ID | The collection contains buttons 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 any buttons on the specified usage page in any report of the specified report type. |
User-mode applications and kernel-mode drivers call HidP_MaxUsageListLength to determine the maximum number of buttons that can be returned for specified report type. Alternatively, applications or drivers can call HidP_GetUsages and set (*UsageLength) to zero to return the required length in UsageLength. In other words, UsageLength should be a valid pointer that points to a ULONG value 0 to get the required length.
Applications or drivers determine the required report length from the XxxReportByteLength members in a top-level collection's HIDP_CAPS structure.
For more information, see HID Collections.