From: Lukasz Majczak lma@semihalf.com

This is shown with Samsung Chromebook Pro (Caroline) with TPM 1.2 (SLB 9670):

[ 4.324298] TPM returned invalid status [ 4.324806] WARNING: CPU: 2 PID: 1 at drivers/char/tpm/tpm_tis_core.c:275 tpm_tis_status+0x86/0x8f

Background ==========

TCG PC Client Platform TPM Profile (PTP) Specification, paragraph 6.1 FIFO Interface Locality Usage per Register, Table 39 Register Behavior Based on Locality Setting for FIFO - a read attempt to TPM_STS_x Registers returns 0xFF in case of lack of locality.

The fix =======

Decorate tpm_tis_gen_interrupt() with request_locality() and release_locality().

Cc: Laurent Bigonville bigon@debian.org Cc: James Bottomley James.Bottomley@HansenPartnership.com Cc: Guenter Roeck linux@roeck-us.net Cc: stable@vger.kernel.org Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()") Signed-off-by: Lukasz Majczak lma@semihalf.com Signed-off-by: Jarkko Sakkinen jarkko@kernel.org --- drivers/char/tpm/tpm_tis_core.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 30843954aa36..a2e0395cbe61 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -707,12 +707,22 @@ static int tpm_tis_gen_interrupt(struct tpm_chip *chip) const char *desc = "attempting to generate an interrupt"; u32 cap2; cap_t cap; + int ret;

+ /* TPM 2.0 */ if (chip->flags & TPM_CHIP_FLAG_TPM2) return tpm2_get_tpm_pt(chip, 0x100, &cap2, desc); - else - return tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, - 0); + + /* TPM 1.2 */ + ret = request_locality(chip, 0); + if (ret < 0) + return ret; + + ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0); + + release_locality(chip, 0); + + return ret; }

/* Register the IRQ and issue a command that will cause an interrupt. If an