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tpm: Adjust the durations if they are too small

Adjust the durations if they are found to be too small, i.e., if they are
returned in milliseconds rather than microseconds as some Infineon TPMs are
reported to do.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Stefan Berger 14 years ago
parent
commit
e934acca1e
1 changed files with 11 additions and 6 deletions
  1. 11 6
      drivers/char/tpm/tpm.c

+ 11 - 6
drivers/char/tpm/tpm.c

@@ -583,17 +583,22 @@ duration:
 	duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 	chip->vendor.duration[TPM_SHORT] =
 	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
+	chip->vendor.duration[TPM_MEDIUM] =
+	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
+	chip->vendor.duration[TPM_LONG] =
+	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
+
 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 	 * value wrong and apparently reports msecs rather than usecs. So we
 	 * fix up the resulting too-small TPM_SHORT value to make things work.
+	 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 	 */
-	if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
+	if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 		chip->vendor.duration[TPM_SHORT] = HZ;
-
-	chip->vendor.duration[TPM_MEDIUM] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
-	chip->vendor.duration[TPM_LONG] =
-	    usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
+		chip->vendor.duration[TPM_MEDIUM] *= 1000;
+		chip->vendor.duration[TPM_LONG] *= 1000;
+		dev_info(chip->dev, "Adjusting TPM timeout parameters.");
+	}
 }
 EXPORT_SYMBOL_GPL(tpm_get_timeouts);