Intel Extensible Firmware Interface - Manual (Page 165)

Services — Boot Services
Version 1.10 12/01/02 5-67
then EFI_INVALID_PARAMETER is returned. If DriverImageHandle is not NULL , and
DriverImageHandle is not currently managing ControllerHandle , then EFI_SUCCESS
is returned. If ChildHandle is not NULL , and ChildHandle is not a valid EFI_HANDLE ,
then EFI_INVALID_PARAMETER is returned. If there are not enough resources available to
disconnect drivers from ControllerHandle , then EFI_OUT_OF_RESOURCES is returned.
Status Codes Returned
EFI_SUCCESS One or more drivers were disconnected from the controller.
EFI_SUCCESS On entry, no drivers are managing ControllerHandle .
EFI_SUCCESS DriverImageHandle is not NULL , and on entry
DriverImageHandle is not managing ControllerHandle .
EFI_INVALID_PARAMETER ControllerHandle is not a valid EFI_HANDLE .
EFI_INVALID_PARAMETER DriverImageHandle is not NULL , and it is not a valid
EFI_HANDLE .
EFI_INVALID_PARAMETER ChildHandle is not NULL , and it is not a valid EFI_HANDLE .
EFI_OUT_OF_RESOURCES There are not enough resources available to disconnect any drivers from
ControllerHandle .
EFI_DEVICE_ERROR The controller could not be disconnected because of a device error.
Examples
//
// Disconnect All Handles Example
//
The following example recusively disconnects all drivers from all
// controllers in a platform.
//
EFI_STATUS Status;
EFI_BOOT_SERVICES_TABLE *gBS;
UINTN HandleCount;
EFI_HANDLE *HandleBuffer;
UINTN HandleIndex;
//
// Retrieve the list of all handles from the handle database
//
Status = gBS->LocateHandleBuffer (
AllHandles,
NULL,
NULL,
&HandleCount,
&HandleBuffer
);
if (!EFI_ERROR (Status)) {
for (HandleIndex = 0; HandleIndex < HandleCount; HandleIndex++) {
Status = gBS->DisconnectController (
HandleBuffer[HandleIndex],
NULL,
NULL
);
}
gBS->FreePool(HandleBuffer);