INF AddInterface Directive

[DDInstall.Interfaces]

AddInterface={InterfaceClassGUID} [, [reference string] [,[add-interface-section] [,flags]]]

One or more AddInterface directives can be specified within an INF DDInstall.Interfaces section. This directive installs device-specific support for device interface classes exported to higher level components, such as other drivers or applications. The directive typically references an add-interface-section , which sets up registry information for the device-specific instance of the device interface class.

An exported device interface class can be one of the system-defined device interface classes, such as those defined by kernel streaming, or a new device interface class specified by an INF InterfaceInstall32 section.

Entry Values

InterfaceClassGUID: Specifies the GUID value that identifies the device interface class. This can be expressed as an explicit GUID value of the form {nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn} or as a %strkey% token defined to "{nnnnnnnn-nnnn-nnnn-nnnn-nnnnnnnnnnnn}" in a Strings section of the INF file.
For more information about how to create a GUID, see Using GUIDs in Drivers. For the system-defined interface class GUIDS, see the appropriate header, such as ks.h for the kernel-streaming interface GUIDs.
reference string: This optional value, associated with the device-specific instance of the specified interface class, can be expressed either as a "quoted string" or as a %strkey% token defined in an INF Strings section.
PnP function and filter drivers usually omit this value from the AddInterface= entries in their INF files.A reference string is used by the swenum driver, as a placeholder for software devices that are created on demand, using multiple instances of a single interface class. The same InterfaceClassGUID value can be specified in INF entries with two or more unique reference strings. Because the I/O Manager passes the reference string value as a path component of the interface instance's name whenever it is opened, the installed driver can discriminate between interface instances of the same class for a single device.
add-interface-section: References the name of a section elsewhere in the INF file, which typically contains an INF AddReg directive to set up the registry entries exporting the driver's support of this device interface class. For more information, see the following Comments section.
flags: If specified, must be zero.

Comments

If the device interface class identified by a given {InterfaceClassGUID} is not installed already, the system setup code installs that class in the system. Any INF file that installs a new class also has an INF InterfaceInstall32 section containing the specified {InterfaceClassGUID} and referencing an interface-install-section that sets up interface-specific installation operations for that class.

To enable an instance of a device interface class for runtime use by higher level components, the driver must make a call IoSetDeviceInterfaceState with each {InterfaceClassGUID} value identifying a device interface class that the driver supports on the underlying device. As an alternative to registering its support for a device interface class in its INF, a device driver can call IoRegisterDeviceInterface before making its initial call to IoSetDeviceInterfaceState. Usually, a PnP function or filter driver makes this call from its AddDevice routine.

Each AddInterface directive in an INF DDInstall.Interfaces section can reference an INF-writer-defined add-interface-section elsewhere in the INF file. Each INF-writer-defined section name must be unique within the INF and must follow the general rules for defining section names. These rules are described in General Syntax Rules for INF Files.

An add-interface-section referenced by the AddInterface directive has the following form:

[add-interface-section]

AddReg=add-registry-section[, add-registry-section]...
[DelReg=del-registry-section[, del-registry-section] ...]
[BitReg=bit-registry-section[,bit-registry-section] ...]
[CopyFiles=@filename | file-list-section[,file-list-section]...]
[DelFiles=file-list-section[,file-list-section]...]
[RenFiles=file-list-section[,file-list-section]...]
[UpdateInis=update-ini-section[, update-ini-section] ...]
[UpdateIniFields=update-inifields-section[, update-inifields-section] ...]
[Ini2Reg=ini-to-registry-section[, ini-to-registry-section] ...]

Typically, an add-interface-section contains only an INF AddReg directive that, in turn, references a single add-registry-section. The add-registry-section is used to store information in the registry about the interfaces supported by the device driver for subsequent use by still higher level drivers and applications.

An add-registry-section referenced within an add-interface-section is both device/driver-specific and interface instance-specific in nature. It might have a value entry defining a friendly name for the exported device interface instance so that still higher level components can refer to that interface by its friendly name in the user interface. An HKR specified in such an add-registry-section section designates the user-mode-accessible device-interface subkey of the ..DeviceClasses\{InterfaceClassGUID}\ branch. In the registry, DeviceClasses is a subkey of the ..CurrentControlSet\Control key.

Example

This example shows some of the expansion of the DDInstall.Interfaces section for a particular audio device that supports system-defined kernel-streaming interfaces.

; ...
[ESS6881.Device.Interfaces]
AddInterface=%KSCATEGORY_AUDIO%,%KSNAME_Wave%,ESSAud.Interface.Wave
AddInterface=%KSCATEGORY_RENDER%,%KSNAME_Wave%,ESSAud.Interface.Wave
AddInterface=%KSCATEGORY_CAPTURE%,%KSNAME_Wave%,ESSAud.Interface.Wave
AddInterface=%KSCATEGORY_AUDIO%,%KSNAME_Topology%,\
ESSAud.Interface.Topology
AddInterface=%KSCATEGORY_AUDIO%,%KSNAME_UART%,WDM.Interface.UART
AddInterface=%KSCATEGORY_RENDER%,%KSNAME_UART%,WDM.Interface.UART
AddInterface=%KSCATEGORY_CAPTURE%,%KSNAME_UART%,WDM.Interface.UART
AddInterface=%KSCATEGORY_AUDIO%,%KSNAME_FMSynth%,WDM.Interface.FMSynth
AddInterface=%KSCATEGORY_RENDER%,%KSNAME_FMSynth%,\
WDM.Interface.FMSynth
 
[ESSAud.Interface.Wave]
AddReg=ESSAud.Interface.Wave.AddReg
 
[ESSAud.Interface.Wave.AddReg]
HKR,,CLSID,,%Proxy.CLSID%
HKR,,FriendlyName,,%ESSAud.Wave.szPname%
; ... 
[WDM.Interface.UART]
AddReg=WDM.Interface.UART.AddReg
 
[WDM.Interface.UART.AddReg]
HKR,,CLSID,,%Proxy.CLSID%
HKR,,FriendlyName,,%WDM.UART.szPname%
; ...
[Strings]
KSCATEGORY_AUDIO="{6994ad04-93ef-11d0-a3cc-00a0c9223196}"
KSCATEGORY_RENDER="{65e8773e-8f56-11d0-a3b9-00a0c9223196}"
KSCATEGORY_CAPTURE="{65e8773d-8f56-11d0-a3b9-00a0c9223196}"
; ...
KSNAME_WAVE="Wave"
KSNAME_UART="UART"
; ...
Proxy.CLSID="{17cca71b-ecd7-11d0-b908-00a0c9223196}"
; ... 
ESSAud.Wave.szPname="ESS AudioDrive" 
; ...

INF AddInterface Directive

Entry Values

Comments

Example

See Also