tpm: Keep CLKRUN enabled throughout the duration of transmit_cmd()
authorAzhar Shaikh <azhar.shaikh@intel.com>
Fri, 22 Dec 2017 20:13:44 +0000 (12:13 -0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 15 Mar 2018 09:54:24 +0000 (10:54 +0100)
commit7cea3381216a304e12dc21fb050e51bf62ed7a11
tree62a27461d42516adcfa3cdbfaaca346d98f154ce
parentf1bb2393fcd005b13857a002d25d9a4ebc6a2398
tpm: Keep CLKRUN enabled throughout the duration of transmit_cmd()

commit b3e958ce4c585bf666de249dc794971ebc62d2d3 upstream.

Commit 5e572cab92f0bb5 ("tpm: Enable CLKRUN protocol for Braswell
systems") disabled CLKRUN protocol during TPM transactions and re-enabled
once the transaction is completed. But there were still some corner cases
observed where, reading of TPM header failed for savestate command
while going to suspend, which resulted in suspend failure.
To fix this issue keep the CLKRUN protocol disabled for the entire
duration of a single TPM command and not disabling and re-enabling
again for every TPM transaction. For the other TPM accesses outside
TPM command flow, add a higher level of disabling and re-enabling
the CLKRUN protocol, instead of doing for every TPM transaction.

Fixes: 5e572cab92f0bb5 ("tpm: Enable CLKRUN protocol for Braswell systems")
Signed-off-by: Azhar Shaikh <azhar.shaikh@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/char/tpm/tpm-interface.c
drivers/char/tpm/tpm_tis.c
drivers/char/tpm/tpm_tis_core.c
drivers/char/tpm/tpm_tis_core.h
include/linux/tpm.h