I don’t have any trouble with 2x2 pixel case on CUDA 11.4.1
With 1x1 input size, I do see the -201 error. (I see it if either input dimension is 1). If this is a concern for you, I suggest filing a bug.
My guess would be that this is a documentation issue, and the documentation may be updated to reflect that this function is not usable when either input dimension is 1.
If you can demonstrate that the equivalent ipp function does something different for this kind of input case, that would bolster any claims you might make to lobby for a change in behavior. You should provide that info in the bug you file.