http://www.phoronix.com/scan.php?page=news_item&px=Linux-3.20-TPM-2.0-Security:
Trusted Platform Module 2.0 (TPM 2.0) is to be supported by the Linux 3.20 kernel. While many Linux users and free software advocates are opposed to TPM, TPM 2.0 is going to be supported by the next version of the mainline Linux kernel. Trusted Platform Module technology has already been supported by the mainline Linux kernel but TPM 2.0 breaks backward compatibility with TPM 1.2. TPM 2.0 supports many more alogirhtms, crypto primitives, root keys, and authorization differences. For those learning about TPM for the first time or are just unfamiliar with the differences to TPM 2.0, see the Wikipedia page for a basic overview and the Trusted Computing Group's TPM 2.0 FAQs. The TPM 2.0 support for the Linux kernel is being pulled in through the security subsystem changes for the 3.20 kernel.