Patch adds method ->update_durations to override returned
durations in case TPM chip misbehaves for TPM 1.2 drivers.
Cc: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
Signed-off-by: Alexey Klimov <aklimov@xxxxxxxxxx>
---
drivers/char/tpm/tpm-interface.c | 18 ++++++++++++++++++
include/linux/tpm.h | 2 ++
2 files changed, 20 insertions(+)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 129f640424b7..5cb90918938d 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -768,6 +768,7 @@ int tpm_get_timeouts(struct tpm_chip *chip)
{
cap_t cap;
unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
+ unsigned long durations[3];
ssize_t rc;
if (chip->flags & TPM_CHIP_FLAG_HAVE_TIMEOUTS)
@@ -877,6 +878,23 @@ int tpm_get_timeouts(struct tpm_chip *chip)
usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
chip->duration[TPM_LONG_LONG] = 0; /* not used under 1.2 */
+ /*
+ * Provide ability for vendor overrides of duration values in case
+ * of misreporting.
+ */
+ if (chip->ops->update_durations != NULL)
+ chip->duration_adjusted =
+ chip->ops->update_durations(chip, durations);
+
+ /* Report and set adjusted timeouts */
+ if (chip->duration_adjusted) {
+
+ dev_info(&chip->dev, HW_ERR "Adjusting reported durations\n");
+ chip->duration[TPM_SHORT] = durations[0];
+ chip->duration[TPM_MEDIUM] = durations[1];
+ chip->duration[TPM_LONG] = durations[2];
+ }
+
/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
* value wrong and apparently reports msecs rather than usecs. So we
* fix up the resulting too-small TPM_SHORT value to make things work.
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 4609b94142d4..d6018431b478 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -43,6 +43,8 @@ struct tpm_class_ops {
u8 (*status) (struct tpm_chip *chip);
bool (*update_timeouts)(struct tpm_chip *chip,
unsigned long *timeout_cap);
+ bool (*update_durations)(struct tpm_chip *chip,
+ unsigned long *durations_cap);
int (*go_idle)(struct tpm_chip *chip);
int (*cmd_ready)(struct tpm_chip *chip);
int (*request_locality)(struct tpm_chip *chip, int loc);
--
2.14.4
