Commit ff75c853 authored Jun 13, 2023 by Alexander Steffen Committed by Greg Kroah-Hartman Sep 23, 2023

tpm_tis: Resend command to recover from data transfer errors



[ Upstream commit 280db21e153d8810ce3b93640c63ae922bcb9e8e ]

Similar to the transmission of TPM responses, also the transmission of TPM
commands may become corrupted. Instead of aborting when detecting such
issues, try resending the command again.

Signed-off-by: Alexander Steffen <Alexander.Steffen@infineon.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 61f5453e

drivers/char/tpm/tpm_tis_core.c

+11 −4

Original line number	Diff line number	Diff line
		@@ -421,10 +421,17 @@ static int tpm_tis_send_main(struct tpm_chip chip, const u8 buf, size_t len)
		int rc;
		u32 ordinal;
		unsigned long dur;
		unsigned int try;

		for (try = 0; try < TPM_RETRY; try++) {
		rc = tpm_tis_send_data(chip, buf, len);
		if (rc < 0)
		if (rc >= 0)
		/* Data transfer done successfully */
		break;
		else if (rc != -EIO)
		/* Data transfer failed, not recoverable */
		return rc;
		}

		/* go and do it */
		rc = tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_GO);