Current version in portage tree is 21.4 (24.4.2014) while latest release is 21.23 (9.10.2015) - https://github.com/openSUSE/hwinfo/releases
So, I've created an ebuild in my overlay as the upgrade required some changes. https://github.com/rindeal/gentoo-overlay/blob/master/sys-apps/hwinfo/hwinfo-21.23.ebuild
commit afe0bf46ddf20c0b3c1bce8ff8ffc5a90fa5070b Author: Justin Lecher <jlec@gentoo.org> Date: Tue Feb 9 15:31:10 2016 +0100 sys-apps/hwinfo: Version Bump Gentoo-Bug: https://bugs.gentoo.org/show_bug.cgi?id=565300 Package-Manager: portage-2.2.27 Signed-off-by: Justin Lecher <jlec@gentoo.org> https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=afe0bf46ddf20c0b3c1bce8ff8ffc5a90fa5070b