tpm: Adjust interface timeouts if they are too small

Adjust the interface timeouts if they are found to be too small, i.e., if
they are returned in milliseconds rather than microseconds as we heared
from Infineon that some (old) Infineon TPMs do.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>

drivers/char/tpm/tpm.c

@@ -534,6 +534,7 @@ void tpm_get_timeouts(struct tpm_chip *chip)
 	struct duration_t *duration_cap;
 	ssize_t rc;
 	u32 timeout;
+	unsigned int scale = 1;
 
 	tpm_cmd.header.in = tpm_getcap_header;
 	tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
@@ -553,17 +554,21 @@ void tpm_get_timeouts(struct tpm_chip *chip)
 	timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 	/* Don't overwrite default if value is 0 */
 	timeout = be32_to_cpu(timeout_cap->a);
+	if (timeout && timeout < 1000) {
+		/* timeouts in msec rather usec */
+		scale = 1000;
+	}
 	if (timeout)
-		chip->vendor.timeout_a = usecs_to_jiffies(timeout);
+		chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 	timeout = be32_to_cpu(timeout_cap->b);
 	if (timeout)
-		chip->vendor.timeout_b = usecs_to_jiffies(timeout);
+		chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 	timeout = be32_to_cpu(timeout_cap->c);
 	if (timeout)
-		chip->vendor.timeout_c = usecs_to_jiffies(timeout);
+		chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 	timeout = be32_to_cpu(timeout_cap->d);
 	if (timeout)
-		chip->vendor.timeout_d = usecs_to_jiffies(timeout);
+		chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 
 duration:
 	tpm_cmd.header.in = tpm_getcap_header;