Greenlandic includes several regional or dialectal variants:
kalaallisut (the dominant dialect, generally used to reference the language for official use in Greenland, and used as the lingua franca between other dialects),
tunumiisut (or Eastern Greenlandic), and
inuktun (or avanersuarmiutut, also known as Northern Greenlandic, or Polar Eskimo, spoken around Thule or Qaanaaq, and closely related to Inuktitut in Canada),
and other variants with lower use: Qavak, Upernavik, Uummannaq, and Qeqertarsuup tunua.
However none of them has a distinct ISO 639-3 code (Greenlandic is still not considered as a macrolanguage). If necessary for some translations, it may be useful to request the addition of variant codes, but as long as they are not registered, these can only be variants encoded as private-use extensions to be conforming with BCP47, with at most 8 characters after 'kl-x-' (such as 'kl-x-tunumiis', or 'kl-x-inuktun'). However these translations will have little use outside Wikimedia before an actual variant code is requested and registered in the IANA database for BCP 47 locale tags. But you should talk in order to try using translations that can be understood by all Greenlandic native speakers in Greenland.
The kal code in ISO 639-2/3 should be reserved for kalaallisut itself, and not tunumiisut or inuktun (which are considered as separate languages in LinguisList and Glottolog, the 3 languages making the Greenlandic macrolanguage with its current ISO 639-1 code kl, which currently remains the only code recommended for BCP 47; but kal will be useful in BCP 47 language tags only when new standard codes will be added for other Greenlandic languages, and all made part of the Greenlandic kl macrolanguage, in order to distinguish them).
