On Thu, Jun 18, 2020 at 04:43:37PM +0300, amirmizi6@gmail.com wrote:

From: Amir Mizinski <redacted>

Detected the following incorrect implementation of the send command:
polling on the TPM_STS.stsValid field followed by checking the
TPM_STS.expect field only once. Since TPM_STS.stsValid represents the
TPM_STS.expect validity, both fields should be polled at the same time.

This fix modifies the signature of wait_for_tpm_stat(), adding an
additional "mask_result" parameter to its call. wait_for_tpm_stat() is now
polling the TPM_STS with a mask and waits for the value in mask_result.
The fix adds the ability to check if certain TPM_STS bits have been
cleared.

This change is also aligned to verifying the CRC on I2C TPM. The CRC
verification should be done after the TPM_STS.expect field is cleared
(TPM received all expected command bytes and set the calculated CRC value
in the register).

In addition, the send command was changed to comply with
TCG_DesignPrinciples_TPM2p0Driver_vp24_pubrev.pdf as follows:
- send all command bytes in one loop
- remove special handling of the last byte

Suggested-by: Benoit Houyere <redacted>
Signed-off-by: Amir Mizinski <redacted>

Reviewed-by: Jarkko Sakkinen <redacted>

If this patch set needs a further update, you could rename the function
as 'tpm_tis_wait_for_stat()' (can be part of this patch). It's better
aligned with other naming and gives better picture of the scope of this
function.

/Jarkko