PI8042_SYNCH_READ_PORT callback function (ntdd8042.h)

Article
02/22/2024

The PI8042_SYNCH_READ_PORT-typed callback routine does a synchronized read from an i8042 port. I8042prt supplies this callback.

Syntax

PI8042_SYNCH_READ_PORT Pi8042SynchReadPort;

NTSTATUS Pi8042SynchReadPort(
  [in]  PVOID Context,
  [out] PUCHAR Value,
  [in]  BOOLEAN WaitForACK
)
{...}

Parameters

[in] Context

Pointer to a context supplied by I8042prt.

[out] Value

Pointer to the UCHAR value returned by the routine.

[in] WaitForACK

Not used.

Return value

The PI8042_SYNCH_READ_PORT callback returns one of the following status values:

Return code	Description
STATUS_SUCCESS	The routine successfully returned a byte.
STATUS_IO_TIMEOUT	The hardware was not ready for a read access.

Remarks

The PI8042_SYNCH_READ_PORT callback can only be used in a PI8042_KEYBOARD_INITIALIZATION_ROUTINE callback. I8042prt specifies the read port callback in the ReadPort parameter that I8042prt inputs to a keyboard initialization routine.

The routine polls the hardware until a read is returned by the hardware or an internal time-out occurs.

Requirements

Requirement	Value
Target Platform	Desktop
Header	ntdd8042.h (include Ntdd8042.h)
IRQL	PASSIVE_LEVEL