upstream_commit = $$(printf '%s\n' '$(OPK_SOURCE_VERSION_UPSTREAM)' | \
	sed 's/^.*~git........~\([0-9a-f]*\).*$$/\1/')
upstream_url_base = https://github.com/qca/open-ath9k-htc-firmware
upstream_url = $(upstream_url_base)/archive/$(upstream_commit).tar.gz
source_archive = ../$(OPK_SOURCE)-$(OPK_SOURCE_VERSION_UPSTREAM).orig.tar.gz

$(source_archive):
	wget -O '$@' "$(upstream_url)"

source: $(source_archive)