Install this version:
emerge -a =net-print/mfc9140cdn-1.1.4
# Copyright 1999-2023 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
EAPI=8
inherit rpm
MY_P="${PN}_cupswrapper_GPL_source_${PV}-0"
DESCRIPTION="Brother's MFC-9140CDN CUPS wrapper"
HOMEPAGE="http://support.brother.com/g/s/id/linux/en/download_prn.html#MFC-9140CDN"
SRC_URI="${MY_P}.tar.gz"
#http://support.brother.com/g/b/downloadend.aspx?c=eu_ot&lang=en&prod=mfc9140cdn_eu_as_cn&os=127&dlid=dlf100408_000&flang=4&type3=576
LICENSE="GNU-2"
SLOT="0"
KEYWORDS="amd64 x86"
IUSE=""
DEPEND=""
RDEPEND="net-print/cups
net-print/mfc9140cdnlpr"
S=${WORKDIR}/"${MY_P}"
src_compile() {
cd brcupsconfpt1
emake
}
src_install() {
exeinto /usr/libexec/cups/filter/
doexe "${FILESDIR}"/brother_lpdwrapper_mfc9140cdn
exeinto /opt/brother/Printers/mfc9140cdn/cupswrapper/
doexe brcupsconfpt1/brcupsconfpt1
insinto /usr/share/cups/model/Brother/
doins PPD/brother_mfc9140cdn_printer_en.ppd
}