tpm2-tools: drop dependency on tpm2-abrmd

tpm2-tools is commonly used with the resource manager, tpm2-abrmd - But it
CAN be used without, E.G. by setting the TPM2TOOLS_TCTI_NAME environment
variable to communicate directly with the kernel driver:

export TPM2TOOLS_TCTI_NAME=device

Either directly with the TPM device (/dev/tpmN) or through the in-kernel
resource manager provided by Linux kernel since 4.12 (/dev/tpmrmN)

For some use cases (E.G. initramfs) it makes sense to use tpm2-tools
without abrmd, so remove the tpm2-abrmd select, and instead a note in the
help text that it may be needed.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

diff --git a/package/tpm2-tools/Config.in b/package/tpm2-tools/Config.in
index cc87e2a1bf187224310aa95947c8118849a9b3c9..d8660a8f71b98107a60dba6ac8dd5e8762bca383 100644 (file)
--- a/package/tpm2-tools/Config.in
+++ b/package/tpm2-tools/Config.in
@@ -8,7 +8,6 @@ config BR2_PACKAGE_TPM2_TOOLS
        select BR2_PACKAGE_LIBCURL
        select BR2_PACKAGE_LIBGLIB2
        select BR2_PACKAGE_OPENSSL
-       select BR2_PACKAGE_TPM2_ABRMD # run-time
        select BR2_PACKAGE_TPM2_TSS
        help
          TPM (Trusted Platform Module) 2.0 CLI tools based on system
@@ -17,6 +16,11 @@ config BR2_PACKAGE_TPM2_TOOLS
          and manage non-volatile storage through a TPM2.0 HW
          implementation.
 
+         Notice: An in-kernel resource manager is provided by the
+         Linux kernel since 4.12. Depending on use cases and kernel
+         version, the user space resource manager provided by
+         tpm2-abrmd may be needed.
+
          https://github.com/tpm2-software/tpm2-tools
 
 comment "tpm2-tools needs a toolchain w/ dynamic library, wchar, threads"