HidP_GetCollectionDescription function (hidpddi.h)

Fills a device description block with collection description and the corresponding report ID information for the specified report descriptor. A HID minidriver generally does not need to call this function. Instead, it returns the report descriptor to Hidclass driver in response to IOCTL_HID_GET_REPORT_DESCRIPTOR.

Syntax

NTSTATUS HidP_GetCollectionDescription(
  [in]  PHIDP_REPORT_DESCRIPTOR ReportDesc,
  [in]  ULONG                   DescLength,
  [in]  POOL_TYPE               PoolType,
  [out] PHIDP_DEVICE_DESC       DeviceDescription
);

Parameters

[in] ReportDesc

A pointer to a UCHAR array that contains the raw report descriptor.

[in] DescLength

The length of the report descriptor array.

[in] PoolType

A POOL_TYPE-value that indicates the pool type from which memory for the linked list is allocated. This includes each HIDP_COLLECTION_DESC array element of HIDP_DEVICE_DESC, each HIDP_PREPARSED_DATA in each HIDP_COLLECTION_DESC, each HIDP_REPORT_IDS array element of HIDP_DEVICE_DESC.

[out] DeviceDescription

A pointer to a HIDP_DEVICE_DESC structure that is populated with device description block filled in collection descriptors as linked lists. This is a caller-allocated structure. However, its HIDP_COLLECTION_DESC array elements and HIDP_REPORT_IDS array elements are allocated by this function.

Return value

HidP_GetCollectionDescription can return one of these values: TRUE if it successfully fills the device description block. Otherwise, it returns FALSE.

Remarks

For a raw report descriptor that is specified by the ReportDesc parameter, HidP_GetCollectionDescription fills in the DeviceDescription block with a caller-allocated linked list of collection descriptors and the corresponding Report ID information that is described by the given report descriptor. The memory for the collection information and the ReportID information is allocated based on the PoolType value.

Requirements