tpm_tis: Add a check for invalid status
authorJames Bottomley <James.Bottomley@HansenPartnership.com>
Mon, 28 Sep 2020 18:00:12 +0000 (11:00 -0700)
committerJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Thu, 1 Oct 2020 21:21:03 +0000 (00:21 +0300)
commit55707d531af62bd87c1b7e8d66fd9798094f9b3b
tree4c874510faad3ff787284e22459493d82e7d1883
parente08c6d3b19930f84a8da8c18710eefdfa48a9ceb
tpm_tis: Add a check for invalid status

Some TIS based TPMs can return 0xff to status reads if the locality
hasn't been properly requested.  Detect this condition by checking the
bits that the TIS spec specifies must return zero are clear and return
zero in that case.  Also drop a warning so the problem can be
identified in the calling path and fixed (usually a missing
try_get_ops()).

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
drivers/char/tpm/tpm_tis_core.c
drivers/char/tpm/tpm_tis_core.h