Merge tag 'tpmdd-next-20190902' of git://git.infradead.org/users/jjs/linux-tpmdd

Pull tpm updates from Jarkko Sakkinen:
 "A new driver for fTPM living inside ARM TEE was added this round.

  In addition to that, there are three bug fixes and one clean up"

* tag 'tpmdd-next-20190902' of git://git.infradead.org/users/jjs/linux-tpmdd:
  tpm/tpm_ftpm_tee: Document fTPM TEE driver
  tpm/tpm_ftpm_tee: A driver for firmware TPM running inside TEE
  tpm: Remove a deprecated comments about implicit sysfs locking
  tpm_tis_core: Set TPM_CHIP_FLAG_IRQ before probing for interrupts
  tpm_tis_core: Turn on the TPM before probing IRQ's
  MAINTAINERS: fix style in KEYS-TRUSTED entry

Documentation/devicetree/bindings/vendor-prefixes.yaml

@@ -575,6 +575,8 @@ patternProperties:
     description: Micro Crystal AG
   "^micron,.*":
     description: Micron Technology Inc.
+  "^microsoft,.*":
+    description: Microsoft Corporation
   "^mikroe,.*":
     description: MikroElektronika d.o.o.
   "^miniand,.*":

Documentation/security/tpm/index.rst

@@ -6,3 +6,4 @@ Trusted Platform Module documentation
 
    tpm_vtpm_proxy
    xen-tpmfront
+   tpm_ftpm_tee

Documentation/security/tpm/tpm_ftpm_tee.rst

@@ -0,0 +1,27 @@
+=============================================
+Firmware TPM Driver
+=============================================
+
+This document describes the firmware Trusted Platform Module (fTPM)
+device driver.
+
+Introduction
+============
+
+This driver is a shim for firmware implemented in ARM's TrustZone
+environment. The driver allows programs to interact with the TPM in the same
+way they would interact with a hardware TPM.
+
+Design
+======
+
+The driver acts as a thin layer that passes commands to and from a TPM
+implemented in firmware. The driver itself doesn't contain much logic and is
+used more like a dumb pipe between firmware and kernel/userspace.
+
+The firmware itself is based on the following paper:
+https://www.microsoft.com/en-us/research/wp-content/uploads/2017/06/ftpm1.pdf
+
+When the driver is loaded it will expose ``/dev/tpmX`` character devices to
+userspace which will enable userspace to communicate with the firmware TPM
+through this device.