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_get_timeouts() with request_locality() and release_locality().
Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()")
Cc: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Cc: Laurent Bigonville <bigon@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Lukasz Majczak <lma@xxxxxxxxxxxx>
Signed-off-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
---
drivers/char/tpm/tpm_tis_core.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 431919d5f48a..30843954aa36 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -1019,11 +1019,21 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
init_waitqueue_head(&priv->read_queue);
init_waitqueue_head(&priv->int_queue);
if (irq != -1) {
- /* Before doing irq testing issue a command to the TPM in polling mode
+ /*
+ * Before doing irq testing issue a command to the TPM in polling mode
* to make sure it works. May as well use that command to set the
* proper timeouts for the driver.
*/
- if (tpm_get_timeouts(chip)) {
+
+ rc = request_locality(chip, 0);
+ if (rc < 0)
+ goto out_err;
+
+ rc = tpm_get_timeouts(chip);
+
+ release_locality(chip, 0);
+
+ if (rc) {
dev_err(dev, "Could not get TPM timeouts and durations\n");
rc = -ENODEV;
goto out_err;
--
2.30.1
