tpm: cmd_ready command can be issued only after granting locality
authorTomas Winkler <tomas.winkler@intel.com>
Mon, 5 Mar 2018 11:34:49 +0000 (13:34 +0200)
committerJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Fri, 23 Mar 2018 08:18:05 +0000 (10:18 +0200)
commit888d867df4417deffc33927e6fc2c6925736fe92
treed587a1e61431f020c9368499a9d3b3daa23f94da
parent5893ed18a26d1f56b97c0290b0cbbc2d49d6de28
tpm: cmd_ready command can be issued only after granting locality

The correct sequence is to first request locality and only after
that perform cmd_ready handshake, otherwise the hardware will drop
the subsequent message as from the device point of view the cmd_ready
handshake wasn't performed. Symmetrically locality has to be relinquished
only after going idle handshake has completed, this requires that
go_idle has to poll for the completion and as well locality
relinquish has to poll for completion so it is not overridden
in back to back commands flow.

Two wrapper functions are added (request_locality relinquish_locality)
to simplify the error handling.

The issue is only visible on devices that support multiple localities.

Fixes: 877c57d0d0ca ("tpm_crb: request and relinquish locality 0")
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkine@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkine@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkine@linux.intel.com>
drivers/char/tpm/tpm-interface.c
drivers/char/tpm/tpm_crb.c
drivers/char/tpm/tpm_tis_core.c
include/linux/tpm.h