From 268f4930212ec67a8c6c976e1368f55c1be732d4 Mon Sep 17 00:00:00 2001 From: Alexander Steffen Date: Tue, 13 Jun 2023 20:02:59 +0200 Subject: [PATCH] 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 Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen Signed-off-by: Sasha Levin --- drivers/char/tpm/tpm_tis_core.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index b95963095729a..f4c4c027b062d 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -512,10 +512,17 @@ 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; - rc = tpm_tis_send_data(chip, buf, len); - if (rc < 0) - return rc; + for (try = 0; try < TPM_RETRY; try++) { + rc = tpm_tis_send_data(chip, buf, len); + if (rc >= 0) + /* Data transfer done successfully */ + break; + else if (rc != -EIO) + /* Data transfer failed, not recoverable */ + return rc; + } rc = tpm_tis_verify_crc(priv, len, buf); if (rc < 0) {