KeyboardClassServiceCallback routine

The KeyboardClassServiceCallback routine is the class service callback routine that is provided by Kbdclass. A function driver calls the class service callback in its ISR dispatch completion routine. The class service callback transfers input data from the input data buffer of a device to the class data queue.

Syntax

VOID KeyboardClassServiceCallback(
  _In_    PDEVICE_OBJECT       DeviceObject,
  _In_    PKEYBOARD_INPUT_DATA InputDataStart,
  _In_    PKEYBOARD_INPUT_DATA InputDataEnd,
  _Inout_ PULONG               InputDataConsumed
);

Parameters

  • DeviceObject [in]
    Pointer to the class device object.

  • InputDataStart [in]
    Pointer to the first keyboard input data packet in the input data buffer of the port device.

  • InputDataEnd [in]
    Pointer to the keyboard input data packet that immediately follows the last data packet in the input data buffer of the port device.

  • InputDataConsumed [in, out]
    Pointer to the number of keyboard input data packets that are transferred by the routine.

Return value

None

Remarks

KeyboardClassServiceCallback transfers input data from the input buffer of the device to the class data queue. This routine is called by the ISR dispatch completion routine of the function driver.

KeyboardClassServiceCallback can be supplemented by a filter service callback that is provided by an upper-level keyboard filter driver. A filter service callback filters the keyboard data that is transferred to the class data queue. For example, the filter service callback can delete, transform, or insert data. Kbfiltr, the sample filter driver in theMSDN Code Galleryt, includes KbFilter_ServiceCallback, which is a template for a keyboard filter service callback.

Requirements

Target platform

Header

Kbdclass.h (include Kbdclass.h)

IRQL

DISPATCH_LEVEL

See also

KbFilter_ServiceCallback

KEYBOARD_INPUT_DATA

 

 

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