PSERVICE_CALLBACK_ROUTINE callback function (kbdmou.h)

Article
10/21/2021

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

PSERVICE_CALLBACK_ROUTINE PserviceCallbackRoutine;

void PserviceCallbackRoutine(
  [in]      PVOID NormalContext,
  [in]      PVOID SystemArgument1,
  [in]      PVOID SystemArgument2,
  [in, out] PVOID SystemArgument3
)
{...}

Parameters

[in] NormalContext

Pointer to the class device object.

[in] SystemArgument1

Pointer to the first keyboard input data packet in the input data buffer of the port device.

[in] SystemArgument2

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

[in, out] SystemArgument3

Pointer to the number of keyboard input data packets that are transferred by the routine.

Return value

None

Remarks

Keyboard Class Service Callback

Here is the definition of the keyboard class service callback routine.

Kbdclass uses an IOCTL_INTERNAL_KEYBOARD_CONNECT request to connect its class service callback to a keyboard device. In this call, the driver sets its implementation in a CONNECT_DATA structure.


/*
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.

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

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 code gallery, includes KbFilter_ServiceCallback, which is a template for a keyboard filter service callback.

Mouse Class Service Callback

Here is the MouseClassServiceCallback routine is the class service callback routine that is provided by Mouclass. The driver uses an IOCTL_INTERNAL_MOUSE_CONNECT request to connect its class service callback to a mouse device. In this call, the driver sets its implementation in a CONNECT_DATA structure.


/*
DeviceObject [in] 
Pointer to the class device object.

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

InputDataEnd [in] 
Pointer to the mouse 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 mouse input data packets that are transferred by the routine.

*/
VOID MouseClassServiceCallback(
  _In_    PDEVICE_OBJECT    DeviceObject,
  _In_    PMOUSE_INPUT_DATA InputDataStart,
  _In_    PMOUSE_INPUT_DATA InputDataEnd,
  _Inout_ PULONG            InputDataConsumed
);
);

MouseClassServiceCallback 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.

MouseClassServiceCallback can be supplemented by a filter service callback that is provided by an upper-level mouse filter driver. A filter service callback can filter the mouse data that is transferred to the class data queue. For example, the filter service callback can delete, transform, or insert data. Moufiltr, the sample filter driver in the WDK, includes MouFilter_ServiceCallback, which is a template for a filter service callback.

Requirements

Requirement	Value
Target Platform	Desktop
Header	kbdmou.h
IRQL	DISPATCH_LEVEL