Unit HID
From Ultibo.org
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Description
Ultibo Human Interface Device (HID) Interface unit
The Human Interface Device (HID) class is intended to provide a flexible model that allows a wide range of control types to be expressed using a standard set of tags in a report descriptor that each device provides during initialization.
HID devices can represent common items such as mice, keyboards, touchscreens, gamepads and joysticks but can also appear as controls within many other types of devices.
A headset for example will primarily be an audio device but the volume and mute buttons can be defined using the HID standard and easily recognized by software without requiring a custom driver for each and every device.
The Ultibo HID implementation creates an intermediate device layer that is mostly agnostic to both the bus type being used by an underlying provider (such as USB) and the devices recognized by HID consumers such as mice and keyboards.
A provider such as USB HID locates devices from the provider specific bus and creates HID devices to represent them along with obtaining report descriptors and other information.
These HID devices are then passed to registered HID consumers (drivers) to determine if they recognize the collections, reports and usages described by the device. A consumer can accept a device and bind to it during this process and create its own devices to represent the functionality described by the HID device.
While HID itself is intended to be bus agnostic this implementation is based heavily on the USB HID standards as those are the most widely adopted at this time. It is anticipated that HID adoption will expand over time to include a range other bus types, Bluetooth is already using HID and there are existing implementations of HID over I2C, SPI and PCI.
Expanding the Ultibo HID support to other bus types simply requires a new HID provider for that bus to be written along with any necessary changes or extensions to the HID layer itself.
Constants
To be documented
Type definitions
HID descriptor
PHIDDescriptor = ^THIDDescriptor;
THIDDescriptor = packed record
| See Section 6.2.1 | |
bLength:Byte;
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bDescriptorType:Byte;
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bcdHID:Word;
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bCountryCode:Byte;
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bNumDescriptors:Byte;
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bHIDDescriptorType:Byte;
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wHIDDescriptorLength:Word;
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| Note: Up to two optional bHIDDescriptorType/wHIDDescriptorLength pairs after the Report descriptor details | |
HID report descriptor
PHIDReportDescriptor = Pointer;
| See Section 6.2.2 | |
HID physical descriptor
PHIDPhysicalDescriptor = ^THIDPhysicalDescriptor;
THIDPhysicalDescriptor = packed record
| See Section 6.2.3 | |
bDesignator:Byte;
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Indicates which part of the body affects the item |
bFlags:Byte;
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Bits specifying flags (7..5 Qualifier / 4..0 Effort) |
HID physical descriptor set0
PHIDPhysicalDescriptorSet0 = ^THIDPhysicalDescriptorSet0;
THIDPhysicalDescriptorSet0 = packed record
bNumber:Byte;
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Number of Physical Descriptor sets not including Physical Descriptor set 0 |
wLength:Word;
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Length of each Physical descriptor set |
HID physical descriptor set
PHIDPhysicalDescriptorSet = ^THIDPhysicalDescriptorSet;
THIDPhysicalDescriptorSet = packed record
bPhysicalInfo:Byte;
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Bits specifying physical information (7..5 Bias / 4..0 Preference) |
wPhysicalDescriptor:array[0..0] of THIDPhysicalDescriptor;
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Physical descriptor data |
HID state
PHIDState = ^THIDState;
THIDState = record
| Local State | |
Usage:LongWord;
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UsageCount:LongWord;
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Provides UsageMinimum/UsageMaximum |
DesignatorIndex:LongWord;
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DesignatorCount:LongWord;
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Provides DesignatorMinimum/DesignatorMaximum |
StringIndex:LongWord;
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StringCount:LongWord;
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Provides StringMinimum/StringMaximum |
Delimiter:Boolean;
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| Global State | |
UsagePage:Word;
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LogicalMinimum:LongInt;
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LogicalMaximum:LongInt;
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PhysicalMinimum:LongInt;
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PhysicalMaximum:LongInt;
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UnitType:LongWord;
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UnitExponent:LongWord;
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ReportSize:LongWord;
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ReportId:LongWord;
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ReportCount:LongWord;
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HID stack
PHIDStack = ^THIDStack;
THIDStack = record
State:PHIDState;
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Next:PHIDStack;
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HID usages
PHIDUsages = ^THIDUsages;
THIDUsages = array[0..0] of PHIDUsage;
HID usage
PHIDUsage = ^THIDUsage;
THIDUsage = record
Page:Word;
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The usage page this usage refers to |
Usage:Word;
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The usage within the usage page |
Count:Word;
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The total number of sequential usages where Usage represents the minimum value or 1 for a single usage (Usage range is from Usage to Usage + Count - 1) |
Index:LongWord;
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The index of this usage in the report (First usage is 0) |
StringIndex:LongWord;
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The string index for this usage |
StringCount:LongWord;
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The total number of sequential string index values where string index represents the minimum value or 1 for a single string |
DesignatorIndex:LongWord;
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The designator index for this usage |
DesignatorCount:LongWord;
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The total number of sequential designator index values where designator index represents the minimum value or 1 for a single designator |
LogicalMinimum:LongInt;
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The logical minimum value for this usage |
LogicalMaximum:LongInt;
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The logical maximum value for this usage |
PhysicalMinimum:LongInt;
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The physical minimum value for this usage (in Units) |
PhysicalMaximum:LongInt;
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The physical maximum value for this usage (in Units) |
UnitType:LongWord;
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The unit type for this usage |
UnitExponent:LongWord;
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The unit exponent index for this usage |
Aliases:PHIDUsages;
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The list of aliased usages for this control (See Delimiters in Section 6.2.2.8) |
AliasCount:LongWord;
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The number of aliased usages contained for this control |
Report:PHIDReport;
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The report this usage belongs to |
HID reports
PHIDReports = ^THIDReports;
THIDReports = array[0..0] of PHIDReport;
HID report
PHIDReport = ^THIDReport;
THIDReport = record
Id:Byte;
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The Id of this report |
Kind:Byte;
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The type of report (Input, Output or Feature) (eg HID_REPORT_INPUT) |
Flags:LongWord;
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The main item flags for this report (eg HID_MAIN_ITEM_VARIABLE) |
Size:LongWord;
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The number of bits per field in this report |
Count:LongWord;
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The number of fields in this report |
Index:LongWord;
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The index of this report in the collection (First report is 0) |
Usages:PHIDUsages;
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The list of usages contained in this report |
UsageCount:LongWord;
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The number of usages contained in this report |
Collection:PHIDCollection;
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The collection this report belongs to |
HID collections
PHIDCollections = ^THIDCollections;
THIDCollections = array[0..0] of PHIDCollection;
HID collection
PHIDCollection = ^THIDCollection;
THIDCollection = record
Page:Word;
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The usage page this collection refers to (eg HID_PAGE_GENERIC_DESKTOP) |
Usage:Word;
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The usage within the usage page (eg HID_DESKTOP_MOUSE) |
Flags:LongWord;
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The main item flags for this collection (eg HID_MAIN_COLLECTION_APPLICATION) |
Start:LongWord;
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The first byte of this collection in the report descriptor |
Reports:PHIDReports;
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The list of reports contained in this collection |
ReportCount:LongWord;
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The number of reports contained in this collection |
Collections:PHIDCollections;
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The list of collections contained in this collection |
CollectionCount:LongWord;
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The number of collections contained in this collection |
Parent:PHIDCollection;
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The parent collection or nil if this is a top level collection |
Device:PHIDDevice;
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The device this collection belongs to |
Consumer:PHIDConsumer;
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The consumer which is bound to this collection (or nil if not bound) |
PrivateData:Pointer;
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Private data for the consumer of this collection |
HID device enumeration callback
THIDDeviceEnumerate = function(Device:PHIDDevice;Data:Pointer):LongWord;
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HID device notification callback
THIDDeviceNotification = function(Device:PDevice; Data:Pointer; Notification:LongWord):LongWord;
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HID device get idle
THIDDeviceGetIdle = function(Device:PHIDDevice; var Duration:Word; ReportId:Byte):LongWord;
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HID device set idle
THIDDeviceSetIdle = function(Device:PHIDDevice; Duration:Word; ReportId:Byte):LongWord;
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HID device get report
THIDDeviceGetReport = function(Device:PHIDDevice; ReportType,ReportId:Byte; ReportData:Pointer; ReportSize:LongWord):LongWord;
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HID device set report
THIDDeviceSetReport = function(Device:PHIDDevice; ReportType,ReportId:Byte; ReportData:Pointer; ReportSize:LongWord):LongWord;
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HID device allocate report
THIDDeviceAllocateReport = function(Device:PHIDDevice; Collection:PHIDCollection; ReportId:Byte; ReportSize:LongWord):LongWord;
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HID device release report
THIDDeviceReleaseReport = function(Device:PHIDDevice; ReportId:Byte):LongWord;
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HID device submit report
THIDDeviceSubmitReport = function(Device:PHIDDevice; ReportId:Byte):LongWord;
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HID device cancel report
THIDDeviceCancelReport = function(Device:PHIDDevice; ReportId:Byte):LongWord;
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HID device get protocol
THIDDeviceGetProtocol = function(Device:PHIDDevice; var Protocol:Byte):LongWord;
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HID device set protocol
THIDDeviceSetProtocol = function(Device:PHIDDevice; Protocol:Byte):LongWord;
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HID device get interval
THIDDeviceGetInterval = function(Device:PHIDDevice; var Interval:LongWord):LongWord;
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HID device set interval
THIDDeviceSetInterval = function(Device:PHIDDevice; Interval:LongWord):LongWord;
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HID device get report descriptor
THIDDeviceGetReportDescriptor = function(Device:PHIDDevice; Descriptor:PHIDReportDescriptor; Size:LongWord):LongWord;
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HID device get physical descriptor set0
THIDDeviceGetPhysicalDescriptorSet0 = function(Device:PHIDDevice; Descriptor:PHIDPhysicalDescriptorSet0):LongWord;
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HID device get physical descriptor set
THIDDeviceGetPhysicalDescriptorSet = function(Device:PHIDDevice; Descriptor:PHIDPhysicalDescriptorSet; Index:Byte; Size:LongWord):LongWord;
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HID device
PHIDDevice = ^THIDDevice;
THIDDevice = record
| Device Properties | |
Device:TDevice;
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The Device entry for this HID |
| HID Properties | |
HIDId:LongWord;
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Unique Id of this HID in the HID device table |
HIDState:LongWord;
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HID device state (eg HID_STATE_ATTACHED) |
Consumer:PHIDConsumer;
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The consumer which is bound to this device (or nil if not bound) |
DeviceGetIdle:THIDDeviceGetIdle;
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A device specific GetIdle method (If supported by provider) |
DeviceSetIdle:THIDDeviceSetIdle;
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A device specific SetIdle method (If supported by provider) |
DeviceGetReport:THIDDeviceGetReport;
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A device specific GetReport method (If supported by provider) |
DeviceSetReport:THIDDeviceSetReport;
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A device specific SetReport method (If supported by provider) |
DeviceAllocateReport:THIDDeviceAllocateReport;
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A device specific AllocateReport method (If supported by provider) |
DeviceReleaseReport:THIDDeviceReleaseReport;
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A device specific ReleaseReport method (If supported by provider) |
DeviceSubmitReport:THIDDeviceSubmitReport;
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A device specific SubmitReport method (If supported by provider) |
DeviceCancelReport:THIDDeviceCancelReport;
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A device specific CancelReport method (If supported by provider) |
DeviceGetProtocol:THIDDeviceGetProtocol;
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A device specific GetProtocol method (If supported by provider) |
DeviceSetProtocol:THIDDeviceSetProtocol;
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A device specific SetProtocol method (If supported by provider) |
DeviceGetInterval:THIDDeviceGetInterval;
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A device specific GetInterval method (If supported by provider) |
DeviceSetInterval:THIDDeviceSetInterval;
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A device specific SetInterval method (If supported by provider) |
DeviceGetReportDescriptor:THIDDeviceGetReportDescriptor;
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A device specific GetReportDescriptor method (If supported by provider) |
DeviceGetPhysicalDescriptorSet0:THIDDeviceGetPhysicalDescriptorSet0;
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A device specific GetPhysicalDescriptorSet0 method (If supported by provider) |
DeviceGetPhysicalDescriptorSet:THIDDeviceGetPhysicalDescriptorSet;
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A device specific GetPhysicalDescriptorSet method (If supported by provider) |
| Driver Properties | |
Lock:TMutexHandle;
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HID device lock |
PrivateData:Pointer;
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Private data for the consumer of this HID device (If applicable) |
Collections:PHIDCollections;
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The parsed report descriptor with collections, reports and usages |
CollectionCount:LongWord;
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The number of top level collections contained in the report descriptor |
Descriptor:PHIDReportDescriptor;
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The raw report descriptor obtained from the device |
DescriptorSize:LongWord;
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The size of the data pointed to by Descriptor |
| Statistics Properties | |
ReceiveCount:LongWord;
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ReceiveErrors:LongWord;
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| Internal Properties | |
Prev:PHIDDevice;
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Previous entry in Device table |
Next:PHIDDevice;
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Next entry in Device table |
HID consumer enumeration callback
THIDConsumerEnumerate = function(Consumer:PHIDConsumer; Data:Pointer):LongWord;
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HID device bind
THIDDeviceBind = function(Device:PHIDDevice):LongWord;
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HID device unbind
THIDDeviceUnbind = function(Device:PHIDDevice):LongWord;
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HID collection bind
THIDCollectionBind = function(Device:PHIDDevice; Collection:PHIDCollection):LongWord;
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HID collection unbind
THIDCollectionUnbind = function(Device:PHIDDevice; Collection:PHIDCollection):LongWord;
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HID report receive
THIDReportReceive = function(Collection:PHIDCollection; ReportId:Byte; ReportData:Pointer; ReportSize:LongWord):LongWord;
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HID consumer
PHIDConsumer = ^THIDConsumer;
THIDConsumer = record
| Driver Properties | |
Driver:TDriver;
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The Driver entry for this HID Consumer |
| Consumer Properties | |
DeviceBind:THIDDeviceBind;
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A Device Bind method to be called when a HID device bind is requested by a provider (Optional) |
DeviceUnbind:THIDDeviceUnbind;
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A Device Ubind method to be called when a HID device unbind is requested by a provider (Optional) |
CollectionBind:THIDCollectionBind;
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A Collection Bind method to be called when a HID collection bind is requested by a provider (Mandatory) |
CollectionUnbind:THIDCollectionUnbind;
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A Collection Unbind method to be called when a HID collection unbind is requested by a provider (Mandatory) |
ReportReceive:THIDReportReceive;
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A Report Receive method to be called when a HID input report is received by a provider (Mandatory) |
| Interface Properties | |
Lock:TMutexHandle;
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Consumer lock |
| Internal Properties | |
Prev:PHIDConsumer;
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Previous entry in Consumer table |
Next:PHIDConsumer;
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Next entry in Consumer table |
HID report field
PHIDField = ^THIDField;
THIDField = record
Page:Word;
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The usage page of this field |
Usage:Word;
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The usage within the usage page |
Count:LongWord;
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The total number of sequential usages where Usage represents the minimum value or 1 for a single usage (Usage range is from Usage to Usage + Count - 1) |
Flags:LongWord;
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The flags for this field |
Size:LongWord;
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The length in bytes of this field within the input, output or feature report |
Bits:LongWord;
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The length in bits of this field within the input, output or feature report |
Offset:LongWord;
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The byte offset of this field within the input, output or feature report |
Shift:LongWord;
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The number shift bits to access this field in the input, output or feature report |
Minimum:LongInt;
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The minimum value for this field (either in logical or physical units) |
Maximum:LongInt;
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The maximum value for this field (either in logical or physical units) |
Multiplier:Double;
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The conversion multiplier for this field from logical to physical units |
Resolution:Double;
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The unit resolution for this field in counts per physical unit |
Next:PHIDField;
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The next field in the list |
HID report definition
PHIDDefinition = ^THIDDefinition;
THIDDefinition = record
Id:Byte;
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The Id of this report |
Kind:Byte;
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The type of this report (Input, Output or Feature) |
Size:LongWord;
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The total length of this input, output or feature report in bytes (Including the Id byte) |
Fields:PHIDField;
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Linked list of fields in this input, output or feature report |
Next:PHIDDefinition;
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The next definition in the list |
Public variables
HID logging
HID_DEFAULT_LOG_LEVEL:LongWord = HID_LOG_LEVEL_DEBUG;
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Minimum level for HID messages. Only messages with level greater than or equal to this will be printed. |
HID_LOG_ENABLED:Boolean;
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Function declarations
Initialization functions
procedure HIDInit;
Description: Initialize the HID unit, device and consumer tables
| Note | Called only during system startup |
|---|
HID functions
function HIDParserParseCollections(Device:PHIDDevice; var Collections:PHIDCollections; var Count:LongWord):LongWord;
Description: Parse the HID report descriptor of the provided device and popuplate the collections, reports and usages
| Device | The HID device to parse collections for |
|---|---|
| Collections | A pointer to the top level collections array to be populated |
| Count | A variable to return the number of top level collections |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDParserFreeCollections(Collections:PHIDCollections; Count:LongWord):LongWord;
Description: Free the collections, reports and usages parsed from a HID report descriptor
| Collections | A pointer to the top level collections array to be freed |
|---|---|
| Count | The number of top level collections in the array |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDParserCountCollections(Device:PHIDDevice; Parent:PHIDCollection):LongWord;
Description: Count the number of collections found in the HID report descriptor of the provided device
| Device | The HID device to count collections for |
|---|---|
| Parent | The parent HID collection, if supplied count child collections else count top level collections |
| Return | The number of collections found, 0 if none for or on error |
function HIDParserCountReports(Device:PHIDDevice; Collection:PHIDCollection):LongWord;
Description: Count the number of reports found in the HID report descriptor of the supplied device and collection
| Device | The HID device to count reports for |
|---|---|
| Collection | The HID collection to count reports for |
| Return | The number of reports found, 0 if none for or on error |
function HIDParserCountUsages(Device:PHIDDevice; Report:PHIDReport):LongWord;
Description: Count the number of usages found in the HID report descriptor for the supplied device and report
| Device | The HID device to count usages for |
|---|---|
| Report | The HID report to count usages for |
| Return | The number of usages found, 0 if none for or on error |
function HIDParserAllocateCollection(Device:PHIDDevice; Parent:PHIDCollection; State:PHIDState; Flags,Start:LongWord):PHIDCollection;
Description: Allocate a HID collection to contain a set of reports and usages from a HID report descriptor
| Device | The HID device containing the collection |
|---|---|
| Parent | The HID collection containing the collection (or nil for a top level collection) |
| State | The current HID parser state |
| Flags | The flags for the collection from the HID report descriptor |
| Start | The starting byte offset of the collection in the HID report descriptor |
| Return | A pointer to the HID collection or nil on error |
function HIDParserAllocateReport(Device:PHIDDevice; Collection:PHIDCollection; State:PHIDState; Kind:Byte; Flags,Index:LongWord):PHIDReport;
Description: Allocate a HID report to contain a set of usages from a HID report descriptor
| Device | The HID device containing the report |
|---|---|
| Collection | The HID collection containing the report |
| State | The current HID parser state |
| Kind | The report kind (eg HID_REPORT_INPUT) |
| Flags | The flags for the report from the HID report descriptor |
| Index | The index of this report in the collection (First report is 0) |
| Return | A pointer to the HID report or nil on error |
function HIDParserAllocateUsage(Device:PHIDDevice; Report:PHIDReport; State:PHIDState; Index:LongWord):PHIDUsage;
Description: Allocate a HID usage from a HID report descriptor
| Device | The HID device containing the usage |
|---|---|
| Report | The HID report containing the usage |
| State | The current HID parser state |
| Index | The index of this usage in the report (First usage is 0) |
| Return | A pointer to the HID usage or nil on error |
function HIDParserUpdateUsage(Device:PHIDDevice; Report:PHIDReport; State:PHIDState; Usage:PHIDUsage):Boolean;
Description: Update a HID usage from a HID report descriptor
| Device | The HID device containing the usage |
|---|---|
| Report | The HID report containing the usage |
| State | The current HID parser state |
| Usage | The HID usage to update |
| Return | True if completed or False on error |
| Note | As usages must precede the main item they relate to in the HID report descriptor they need to be allocated before all the required information is known, this function updates the usage after the main item is found. |
function HIDParserPopStack(var Stack:PHIDStack; var State:PHIDState):LongWord;
Description: Replace the current HID parser state with the top item from the parser stack
| Stack | The HID parser stack |
|---|---|
| State | The HID parser state to replace |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDParserPushStack(Stack:PHIDStack):LongWord;
Description: Place a copy of the current HID parser state on top of the parser stack
| Stack | The HID parser stack |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDParserFreeStack(Stack:PHIDStack):LongWord;
Description: Free the HID parser stack and state
| Stack | The HID parser stack |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDParserResetState(State:PHIDState):LongWord;
Description: Clear the Local and Global HID parser state
| State | The HID parser state to reset |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDParserCleanState(State:PHIDState):LongWord;
Description: Clear the Local HID parser state
| State | The HID parser state to clean |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDFindCollection(Device:PHIDDevice; Page,Usage:Word):PHIDCollection;
Description: Find the first HID collection matching the specified page and usage
| Device | The HID device to find collections from |
|---|---|
| Page | The HID Usage Page to match (eg HID_PAGE_GENERIC_DESKTOP) |
| Usage | The HID Usage to match (eg HID_DESKTOP_MOUSE) |
| Return | A pointer to the first matching collection or nil if not matched |
function HIDFindReportIds(Device:PHIDDevice; Collection:PHIDCollection; var MinId,MaxId:Byte):LongWord;
Description: Find the minimum and maximum report ids contained in the specified HID collection or all collections
| Device | The HID device to find report ids from |
|---|---|
| Collection | The HID collection to find report ids from (or nil to find from all collections) |
| MinId | A variable to receive the minimum report id number |
| MaxId | A variable to receive the maximum report id number |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDAllocateDefinition(Device:PHIDDevice; Collection:PHIDCollection; Kind,Id:Byte):PHIDDefinition;
Description: Allocate a HID defintion to describe an input, output or feature report contained in the specified collection
| Device | The HID device to create the report definition from |
|---|---|
| Collection | The HID collection to create the report definition from |
| Kind | The report kind to create a definition for (eg HID_REPORT_INPUT) |
| Id | The report id to create a definition for (must be less than or equal to the maximum report id) |
| Return | A pointer to the allocated definition or nil on error |
function HIDFreeDefinition(Definition:PHIDDefinition):LongWord;
Description: Free a HID definition to describing an input, output or feature report
| Definition | The HID definition to be freed |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDInsertBitField(Field:PHIDField; Buffer:Pointer; Size:LongWord; Value:Boolean):LongWord;
Description: Insert a bit field value into a report buffer
| Field | The field to insert into the report |
|---|---|
| Buffer | A pointer to the report buffer |
| Size | The size in bytes of the report buffer |
| Value | The value to insert into the buffer |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDInsertSignedField(Field:PHIDField; Buffer:Pointer; Size:LongWord; Value:LongInt):LongWord;
Description: Insert a signed field value into a report buffer
| Field | The field to insert into the report |
|---|---|
| Buffer | A pointer to the report buffer |
| Size | The size in bytes of the report buffer |
| Value | The value to insert into the buffer |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDInsertUnsignedField(Field:PHIDField; Buffer:Pointer; Size,Value:LongWord):LongWord;
Description: Insert an unsigned field value into a report buffer
| Field | The field to insert into the report |
|---|---|
| Buffer | A pointer to the report buffer |
| Size | The size in bytes of the report buffer |
| Value | The value to insert into the buffer |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDExtractBitField(Field:PHIDField; Buffer:Pointer; Size:LongWord; var Value:Boolean):LongWord;
Description: Extract a bit field value from a report buffer
| Field | The field to extract from the report |
|---|---|
| Buffer | A pointer to the report buffer |
| Size | The size in bytes of the report buffer |
| Value | A variable to receive the extracted value |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDExtractSignedField(Field:PHIDField; Buffer:Pointer; Size:LongWord; var Value:LongInt):LongWord;
Description: Extract a signed field value from a report buffer
| Field | The field to extract from the report |
|---|---|
| Buffer | A pointer to the report buffer |
| Size | The size in bytes of the report buffer |
| Value | A variable to receive the extracted value |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDExtractUnsignedField(Field:PHIDField; Buffer:Pointer; Size:LongWord; var Value:LongWord):LongWord;
Description: Extract an unsigned field value from a report buffer
| Field | The field to extract from the report |
|---|---|
| Buffer | A pointer to the report buffer |
| Size | The size in bytes of the report buffer |
| Value | A variable to receive the extracted value |
| Return | ERROR_SUCCESS if completed or another error code on failure |
HID Device functions
function HIDDeviceSetState(Device:PHIDDevice; State:LongWord):LongWord;
Description: Set the state of the specified HID device and send a notification
| Device | The HID device to set the state for |
|---|---|
| State | The new state to set and notify (eg HID_STATE_ATTACHED) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceGetIdle(Device:PHIDDevice; var Duration:Word; ReportId:Byte):LongWord;
Description: Get the idle rate from a HID device for the specified report id
| Device | The HID device to get the idle rate from |
|---|---|
| Duration | A variable to receive the idle rate (in Milliseconds) |
| ReportId | The report id to get the idle rate from |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceSetIdle(Device:PHIDDevice; Duration:Word; ReportId:Byte):LongWord;
Description: Set the idle rate on a HID device for the specified report id
| Device | The HID device to set the idle rate for |
|---|---|
| Duration | The idle rate to set (in Milliseconds) |
| ReportId | The report id to set the idle rate for |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceGetReport(Device:PHIDDevice; ReportType,ReportId:Byte; ReportData:Pointer; ReportSize:LongWord):LongWord;
Description: Read a report by type and id from a HID device
| Device | The HID device to read the report from |
|---|---|
| ReportType | The report type to read (eg HID_REPORT_INPUT) |
| ReportId | The report id to read (eg HID_REPORTID_NONE) |
| ReportData | A pointer to a buffer to receive the report data |
| ReportSize | The size in bytes of the buffer pointed to by report data |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceSetReport(Device:PHIDDevice; ReportType,ReportId:Byte; ReportData:Pointer; ReportSize:LongWord):LongWord;
Description: Write a report by type and id to a HID device
| Device | The HID device to write the report to |
|---|---|
| ReportType | The report type to write (eg HID_REPORT_OUTPUT) |
| ReportId | The report id to write (eg HID_REPORTID_NONE) |
| ReportData | A pointer to a buffer containing the report data |
| ReportSize | The size in bytes of the buffer pointed to by report data |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceAllocateReport(Device:PHIDDevice; Collection:PHIDCollection; ReportId:Byte; ReportSize:LongWord):LongWord;
Description: Allocate and initialize an input report by id on a HID device
| Device | The HID device to allocate the report on |
|---|---|
| Collection | The HID collection this request corresponds to |
| ReportId | The report id to allocate (eg HID_REPORTID_NONE) |
| ReportSize | The size in bytes to allocate for the report (Provider will handle alignment and other requirements) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
| Note | An allocated report must be submitted before reports will be received from the device |
function HIDDeviceReleaseReport(Device:PHIDDevice; ReportId:Byte):LongWord;
Description: Release an input report by id from a HID device
| Device | The HID device to release the report from |
|---|---|
| ReportId | The report id to allocate (eg HID_REPORTID_NONE) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
| Note | If the report has been submitted it must be cancelled before being released |
function HIDDeviceSubmitReport(Device:PHIDDevice; ReportId:Byte):LongWord;
Description: Submit an input report by id on a HID device
| Device | The HID device to submit the report on |
|---|---|
| ReportId | The report id to submit (eg HID_REPORTID_NONE) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
| Note | The report must be allocated then submitted before reports will be received from the device |
function HIDDeviceCancelReport(Device:PHIDDevice; ReportId:Byte):LongWord;
Description: Cancel an input report by id on a HID device
| Device | The HID device to cancel the report on |
|---|---|
| ReportId | The report id to cancel (eg HID_REPORTID_NONE) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
| Note | The report should be cancelled then released to stop receiving reports from the device |
function HIDDeviceGetProtocol(Device:PHIDDevice; var Protocol:Byte):LongWord;
Description: Get the report protocol from a HID device
| Device | The HID device to get the report protocol from |
|---|---|
| Protocol | A variable to receive the report protocol (eg HID_PROTOCOL_REPORT) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceSetProtocol(Device:PHIDDevice; Protocol:Byte):LongWord;
Description: Set the report protocol for a HID device
| Device | The HID device to set the report protocol for |
|---|---|
| Protocol | The report protocol to set (eg HID_PROTOCOL_REPORT) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceGetInterval(Device:PHIDDevice; var Interval:LongWord):LongWord;
Description: Get the polling interval from a HID device
| Device | The HID device to get the polling interval from |
|---|---|
| Interval | A variable to receive the polling interval (in Milliseconds) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceSetInterval(Device:PHIDDevice; Interval:LongWord):LongWord;
Description: Set the polling interval for a HID device
| Device | The HID device to set the polling interval for |
|---|---|
| Interval | The polling interval to set (in Milliseconds) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceGetReportDescriptor(Device:PHIDDevice; Descriptor:PHIDReportDescriptor; Size:LongWord):LongWord;
Description: Get the Report Descriptor for a HID device
| Device | The HID device to get the descriptor for |
|---|---|
| Descriptor | Pointer to a buffer to return the HID Report Descriptor |
| Size | The size in bytes of the buffer pointed to by Descriptor |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceGetPhysicalDescriptorSet0(Device:PHIDDevice; Descriptor:PHIDPhysicalDescriptorSet0):LongWord;
Description: Get the HID Physical Descriptor Set 0 for a HID device
| Device | The HID device to get the descriptor for |
|---|---|
| Descriptor | Pointer to a HID Physical Descriptor Set 0 structure for the returned data |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceGetPhysicalDescriptorSet(Device:PHIDDevice; Descriptor:PHIDPhysicalDescriptorSet; Index:Byte; Size:LongWord):LongWord;
Description: Get a HID Physical Descriptor Set for a HID device
| Device | The HID device to get the descriptor for |
|---|---|
| Descriptor | Pointer to a HID Physical Descriptor Set structure for the returned data |
| Index | The index of the physical descriptor set to return |
| Size | The size in bytes of the buffer pointed to by Descriptor |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceBindDevice(Device:PHIDDevice):LongWord;
Description: Attempt to bind a HID device to one of the registered consumers
| Device | The HID device to attempt to bind a consumer to |
|---|---|
| Return | ERROR_SUCCESS if completed, ERROR_NOT_SUPPORTED if unsupported or another error code on failure |
function HIDDeviceUnbindDevice(Device:PHIDDevice; Consumer:PHIDConsumer):LongWord;
Description: Unbind a HID device from a consumer
| Device | The HID device to unbind a consumer from |
|---|---|
| Consumer | The consumer to unbind the device from (nil to unbind from current consumer) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceBindCollections(Device:PHIDDevice):LongWord;
Description: Attempt to bind the HID collections in the specified device to one of the registered consumers
| Device | The HID device containing the collections to attempt to bind a consumer to |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceUnbindCollections(Device:PHIDDevice; Consumer:PHIDConsumer):LongWord;
Description: Unbind the HID collections in the specified device from a consumer
| Device | The HID device containing the collections to unbind a consumer from |
|---|---|
| Consumer | The consumer to unbind the collections from (nil to unbind from current consumer) |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceCreate:PHIDDevice;
Description: Create a new HID device entry
| Return | Pointer to new HID device entry or nil if HID device could not be created |
|---|
function HIDDeviceCreateEx(Size:LongWord):PHIDDevice;
Description: Create a new HID device entry
| Size | Size in bytes to allocate for new HID device (Including the HID device entry) |
|---|---|
| Return | Pointer to new HID device entry or nil if HID device could not be created |
function HIDDeviceDestroy(Device:PHIDDevice):LongWord;
Description: Destroy an existing HID device entry
| Device | The HID device to destroy |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceRegister(Device:PHIDDevice):LongWord;
Description: Register a new HID device in the HID device table
| Device | The HID device to register |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceDeregister(Device:PHIDDevice):LongWord;
Description: Deregister a HID device from the HID device table
| Device | The HID device to deregister |
|---|---|
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceFind(HIDId:LongWord):PHIDDevice;
Description: Find a HID device by ID in the HID device table
| HIDId | The ID number of the HID device to find |
|---|---|
| Return | Pointer to HID device entry or nil if not found |
function HIDDeviceFindByName(const Name:String):PHIDDevice; inline;
Description: Find a HID device by name in the device table
| Name | The name of the HID device to find (eg HID0) |
|---|---|
| Return | Pointer to HID device entry or nil if not found |
function HIDDeviceFindByDescription(const Description:String):PHIDDevice; inline;
Description: Find a HID device by description in the device table
| Description | The description of the HID to find (eg Optical USB Mouse) |
|---|---|
| Return | Pointer to HID device entry or nil if not found |
function HIDDeviceEnumerate(Callback:THIDDeviceEnumerate; Data:Pointer):LongWord;
Description: Enumerate all HID devices in the HID device table
| Callback | The callback function to call for each HID device in the table |
|---|---|
| Data | A private data pointer to pass to callback for each HID device in the table |
| Return | ERROR_SUCCESS if completed or another error code on failure |
function HIDDeviceNotification(Device:PHIDDevice; Callback:THIDDeviceNotification; Data:Pointer; Notification,Flags:LongWord):LongWord;
Description: Register a notification for HID device changes
| Device | The HID device to notify changes for (Optional, pass nil for all HID devices) |
|---|---|
| Callback | The function to call when a notification event occurs |
| Data | A private data pointer to pass to callback when a notification event occurs |
| Notification | The events to register for notification of (eg DEVICE_NOTIFICATION_REGISTER) |
| Flags | The flags to control the notification (eg NOTIFIER_FLAG_WORKER) |
HID consumer functions
function HIDConsumerCreate:PHIDConsumer;
Description: Create a new HID Consumer entry
| Return | Pointer to new Consumer entry or nil if consumer could not be created |
|---|
function HIDConsumerCreateEx(Size:LongWord):PHIDConsumer;
Description: Create a new HID Consumer entry
| Size | Size in bytes to allocate for new consumer (Including the consumer entry) |
|---|---|
| Return | Pointer to new Consumer entry or nil if consumer could not be created |
function HIDConsumerDestroy(Consumer:PHIDConsumer):LongWord;
Description: Destroy an existing HID Consumer entry
| Note | None documented |
|---|
function HIDConsumerRegister(Consumer:PHIDConsumer):LongWord;
Description: Register a new Consumer in the HID Consumer table
| Note | None documented |
|---|
function HIDConsumerDeregister(Consumer:PHIDConsumer):LongWord;
Description: Deregister a Consumer from the HID Consumer table
| Note | None documented |
|---|
function HIDConsumerFind(ConsumerId:LongWord):PHIDConsumer;
Description: Find a consumer by Id in the HID Consumer table
| Note | None documented |
|---|
function HIDConsumerFindByName(const Name:String):PHIDConsumer; inline;
Description: Find a consumer by name in the Driver table
| Note | None documented |
|---|
function HIDConsumerEnumerate(Callback:THIDConsumerEnumerate; Data:Pointer):LongWord;
Description: Enumerate all consumers in the HID Consumer table
| Note | None documented |
|---|
HID helper functions
function HIDIsBitField(Field:PHIDField):Boolean;
Description: Return True if the supplied field contains a 1 bit value
| Note | None documented |
|---|
function HIDIsByteField(Field:PHIDField):Boolean;
Description: Return True if the supplied HID field contains a 1 byte value
| Note | None documented |
|---|
function HIDIsWordField(Field:PHIDField):Boolean;
Description: Return True if the supplied HID field contains a 2 byte value
| Note | None documented |
|---|
function HIDIsLongField(Field:PHIDField):Boolean;
Description: Return True if the supplied HID field contains a 3 or 4 byte value
| Note | None documented |
|---|
function HIDIsSignedField(Field:PHIDField):Boolean;
Description: Return True if the supplied HID field contains a signed value
| Note | None documented |
|---|
function HIDPageToString(Page:Word):String;
Description: Return a string describing a HID usage page
| Note | None documented |
|---|
function HIDUsageToString(Page,Usage,Count:Word):String;
Description: Return a string describing a HID usage within the given page
| Note | None documented |
|---|
function HIDUnitTypeToString(UnitType:LongWord):String;
Description: Return a string describing a HID unit type
| Note | None documented |
|---|
function HIDReportKindToString(Kind:Byte):String;
Description: Return a string describing a HID report type
| Note | None documented |
|---|
function HIDReportFlagsToString(Flags:LongWord):String;
Description: Return a string describing the flags of a HID report
| Note | None documented |
|---|
function HIDCollectionFlagsToString(Flags:LongWord):String;
Description: Return a string describing the flags of a HID collection
| Note | None documented |
|---|
procedure HIDLog(Level:LongWord; Device:PHIDDevice; const AText:String);
Description: To be documented
| Note | None documented |
|---|
procedure HIDLogInfo(Device:PHIDDevice; const AText:String); inline;
Description: To be documented
| Note | None documented |
|---|
procedure HIDLogWarn(Device:PHIDDevice; const AText:String); inline;
Description: To be documented
| Note | None documented |
|---|
procedure HIDLogError(Device:PHIDDevice; const AText:String); inline;
Description: To be documented
| Note | None documented |
|---|
procedure HIDLogDebug(Device:PHIDDevice; const AText:String); inline;
Description: To be documented
| Note | None documented |
|---|
HID device helper functions
function HIDDeviceGetCount:LongWord; inline;
Description: Get the current HID Device count
| Note | None documented |
|---|
function HIDDeviceCheck(Device:PHIDDevice):PHIDDevice;
Description: Check if the supplied HID Device is in the device table
| Note | None documented |
|---|
function HIDDeviceTypeToString(HIDType:LongWord):String;
Description: Return a string describing the HID device type (eg HID_TYPE_USB)
| Note | None documented |
|---|
function HIDDeviceStateToString(HIDState:LongWord):String;
Description: Return a string describing the HID device state (eg HID_STATE_ATTACHED)
| Note | None documented |
|---|
function HIDDeviceStateToNotification(State:LongWord):LongWord;
Description: Convert a Device state value into the notification code for device notifications
| Note | None documented |
|---|
HID consumer helper functions
function HIDConsumerGetCount:LongWord; inline;
Description: Get the current HID Consumer count
| Note | None documented |
|---|
function HIDConsumerCheck(Consumer:PHIDConsumer):PHIDConsumer;
Description: Check if the supplied HID Consumer is in the consumer table
| Note | None documented |
|---|
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