Using the CONNECT_LINE_BASED Version of IoConnectInterruptEx

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For Windows Vista and later operating systems, a driver can use the CONNECT_LINE_BASED version of IoConnectInterruptEx to register an InterruptService routine for the driver's line-based interrupts. (Driver for earlier operating systems can use the CONNECT_FULLY_SPECIFIED version of IoConnectInterruptEx.)

Note   You can use this method only for drivers that register a single interrupt service routine (ISR) for all of its line-based interrupts. If the driver can receive multiple interrupts, it must use the CONNECT_FULLY_SPECIFIED version of IoConnectInterruptEx.

The driver specifies a value of CONNECT_LINE_BASED for Parameters->Version and uses the members of Parameters->LineBased to specify the other parameters of the operation:

  • Parameters->LineBased.PhysicalDeviceObject specifies the physical device object (PDO) for the device that the ISR services. The system uses the device object to automatically identify the device's line-based interrupts.

  • Parameters->LineBased.ServiceRoutine points to the InterruptService routine, while Parameters->LineBased.ServiceContext specifies the value that the system passes as the ServiceContext parameter to InterruptService. The driver can use this to pass context information. For more information about passing context information, see Providing ISR Context Information.

  • The driver provides a pointer to a PKINTERRUPT variable in Parameters->LineBased.InterruptObject. IoConnectInterruptEx sets this variable to point to the interrupt object for the interrupt, which can be used when removing the ISR. For more information, see Removing an ISR.

  • Drivers can optionally specify a spin lock in Parameters->LineBased.SpinLock for the system to use when synchronizing with the ISR. Most drivers can just specify NULL to enable the system to allocate a spin lock on behalf of the driver. For more information about synchronizing with an ISR, see Synchronizing Access to Device Data.

The following code example demonstrates how to register an InterruptService routine using CONNECT_LINE_BASED:

IO_CONNECT_INTERRUPT_PARAMETERS params;

// deviceExtension is a pointer to the driver's device extension. 
//     deviceExtension->IntObj is a PKINTERRUPT.
// deviceInterruptService is a pointer to the driver's InterruptService routine.
// PhysicalDeviceObject is a pointer to the device's PDO. 
// ServiceContext is a pointer to driver-specified context for the ISR.

RtlZeroMemory( &params, sizeof(IO_CONNECT_INTERRUPT_PARAMETERS) );
params.Version = CONNECT_LINE_BASED;
params.LineBased.PhysicalDeviceObject = PhysicalDeviceObject;
params.LineBased.InterruptObject = &deviceExtension->IntObj;
params.LineBased.ServiceRoutine = deviceInterruptService;
params.LineBased.ServiceContext = ServiceContext;
params.LineBased.SpinLock = NULL;
params.LineBased.SynchronizeIrql = 0;
params.LineBased.FloatingSave = FALSE;

status = IoConnectInterruptEx(&params);

if (!NT_SUCCESS(status)) {
    // Operation failed. Handle error.
    ...
}