edk2 cannot find i2c bus - i2c

Question

I am new to UEFI and I am attempting to talk to an i2c bus on an Up eXtreme board. I have tried following people trying similar things with USB online but gBS->LocateHandleBuffer does not seem to find the i2c bus. I am led to assume that since i2c behaves differently to USB I may not be able to take the same approach with it, but I have no way of confirming my suspicions.
At this point any tips/pointers would be appreciated.
EFI_STATUS
EFIAPI
UefiMain(
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE* SystemTable
)
{
EFI_STATUS Status;
EFI_HANDLE* HandleBuffer = NULL;
UINTN HandleCount = 17;
Print(L"HandleCount: %x\n", HandleCount);
Print(L"HandleBuffer: %x\n", HandleBuffer);
UINTN* freq = (UINTN*)23;
EFI_I2C_DEVICE* i2cDescriptor;
EFI_I2C_ENUMERATE_PROTOCOL* enumerateI2c;
Status = gBS->LocateHandleBuffer(ByProtocol,
&gEfiI2cEnumerateProtocolGuid,
NULL,
&HandleCount,
&HandleBuffer);
if (EFI_ERROR(Status)) {
Print(L"ERROR: LocateHandleBuffer.\n");
Print(L"Status: %x\n", (int)Status);
Print(L"HandleCount: %x\n", HandleCount);
Print(L"HandleBuffer: %x\n", HandleBuffer);
return Status;
}
for (UINT8 Index = 0; Index < HandleCount; Index++) {
Status = gBS->HandleProtocol(HandleBuffer[Index],
&gEfiI2cEnumerateProtocolGuid,
(VOID**)&enumerateI2c);
if (EFI_ERROR(Status)) {
Print(L"ERROR: HandleProtocol.\n");
Print(L"Status: %x\n", (int)Status);
Print(L"HandleCount: %x\n", HandleCount);
Print(L"HandleBuffer: %x\n", HandleBuffer);
FreePool(HandleBuffer);
return Status;
}
Status = enumerateI2c->Enumerate(enumerateI2c, &i2cDescriptor);
Print(L"Starting to enumerate\n");
if (EFI_ERROR(Status)) {
Print(L"ERROR: Enumerate.\n");
Print(L"Status: %x\n", (int)Status);
Print(L"HandleCount: %x\n", HandleCount);
Print(L"HandleBuffer: %x\n", HandleBuffer);
FreePool(HandleBuffer);
return Status;
}
Print(L"Enumeration complete\nGetting Bus frequency\n");
Status = enumerateI2c->GetBusFrequency(enumerateI2c, i2cDescriptor->I2cBusConfiguration, freq);
if (EFI_ERROR(Status)) {
Print(L"ERROR: GetBusFrequency.\n");
Print(L"Status: %x\n", (int)Status);
FreePool(HandleBuffer);
return Status;
}
Print(L"Found Frequency:\n");
Print(L"%d\n", (CHAR16*)freq);
}
FreePool(HandleBuffer);
return EFI_SUCCESS;
}

Answer 1

not all UEFI features and drivers are supported on each UEFI firmware.
try to run the app on different hardwares, and see if they support the protocol.
sadly if the protocol does not exists, you have two options:
to implement the low level api.
find someone who has done what is written in 1.