tpm: Add field upgrade mode support for Infineon TPM2 modules

TPM2_GetCapability with a capability that has the property type value
of TPM_PT_TOTAL_COMMANDS returns a zero length list, when an Infineon
TPM2 is in field upgrade mode.
Since an Infineon TPM2.0 in field upgrade mode returns RC_SUCCESS on
TPM2_Startup, the field upgrade mode has to be detected by
TPM2_GetCapability.

Signed-off-by: Stefan Mahnke-Hartmann <stefan.mahnke-hartmann@infineon.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 04a3e23a4afc745d51a0625582379ecfa309db1f..c1eb5d223839579e087a27774bf3adb9f2b45f21 100644 (file)
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -754,7 +754,11 @@ int tpm2_auto_startup(struct tpm_chip *chip)
        rc = tpm2_get_cc_attrs_tbl(chip);
 
 out:
-       if (rc == TPM2_RC_UPGRADE) {
+       /*
+        * Infineon TPM in field upgrade mode will return no data for the number
+        * of supported commands.
+        */
+       if (rc == TPM2_RC_UPGRADE || rc == -ENODATA) {
                dev_info(&chip->dev, "TPM in field upgrade mode, requires firmware upgrade\n");
                chip->flags |= TPM_CHIP_FLAG_FIRMWARE_UPGRADE;
                rc = 0;