I've sent pull requests [1, 2] to the maintainer to upgrade his work-in-progress packages to the latest upstream versions, as well as overhaul the Debian packaging--these should be pretty much production-quality now. I upstreamed some of the patches while I was at it, too.
Additionally, I've created binary Bullseye releases of libtpms v0.8.4 [3] and swtpm v0.6.0 [4] in my forked repositories for anyone who'd like to try them out now. Nick -- [1] https://salsa.debian.org/debian/libtpms/-/merge_requests [2] https://salsa.debian.org/kkamagui/swtpm/-/merge_requests [3] https://salsa.debian.org/nchevsky/libtpms/-/releases/debian%252F0.8.4-1.0 [4] https://salsa.debian.org/nchevsky/swtpm/-/releases/debian%252F0.6.0-1.0