[Skiboot] [PATCH 08/14] tpm_i2c_nuvoton: handle errors after writing sts.go

[Claudio Carvalho]

This handles errors returned by the tpm-i2c interface after writing
sts.go in tpm_transmit().

Fixes: 56ad053c3e8bf0764ad5878cb018f00a389d30cf
Signed-off-by: Claudio Carvalho <cclaudio at linux.vnet.ibm.com>
---
 libstb/drivers/tpm_i2c_nuvoton.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/libstb/drivers/tpm_i2c_nuvoton.c b/libstb/drivers/tpm_i2c_nuvoton.c
index 62236e4..aba7211 100644
--- a/libstb/drivers/tpm_i2c_nuvoton.c
+++ b/libstb/drivers/tpm_i2c_nuvoton.c
@@ -436,10 +436,19 @@ static int tpm_transmit(struct tpm_dev *dev, uint8_t* buf, size_t cmdlen,
 	if (rc < 0)
 		goto out;
 
-	DBG("step 3/5: write tpmgo\n");
+	DBG("step 3/5: write sts.go\n");
 	rc = tpm_status_write_byte(TPM_STS_GO);
-	if (rc < 0)
+	if (rc < 0) {
+		/**
+		 * @fwts-label TPMWriteGo
+		 * @fwts-advice Either the tpm device or the tpm-i2c interface
+		 * doesn't seem to be working properly. Check the return code
+		 * (rc) for further details.
+		 */
+		prlog(PR_ERR, "NUVOTON: fail to write sts.go, rc=%d\n", rc);
+		rc = STB_DRIVER_ERROR;
 		goto out;
+	}
 
 	DBG("step 4/5: read FIFO\n");
 	rc = tpm_read_fifo(buf, buflen);
-- 
1.9.1