tpm: tpm_tis: Add settle time for some TPMs

Some TPMs fail to grant locality when requested immediately after being
relinquished. In this case, the TPM_ACCESS_REQUEST_USE bit of the
TPM_ACCESS register is cleared immediately without setting
TPM_ACCESS_ACTIVE_LOCALITY.

This issue can be seen at boot since tpm_chip_start, called right
after locality is relinquished, will fail. This causes the probe to
fail:

tpm_tis MSFT0101:00: probe with driver tpm_tis failed with error -1

This occurs on some older Dell Latitudes. For the Nuvoton TPM used in
these machines, add a delay after locality is relinquished.

Signed-off-by: Jim Broadus <jbroadus@gmail.com>
Link: https://lore.kernel.org/r/20260526232245.5409-3-jbroadus@gmail.com
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>

0 files changed, 0 insertions, 0 deletions