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>
This commit is contained in:
Stefan Berger 2011-03-30 12:13:24 -04:00 committed by Rajiv Andrade
parent 979b140614
commit e934acca1e

View File

@ -583,17 +583,22 @@ void tpm_get_timeouts(struct tpm_chip *chip)
duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
chip->vendor.duration[TPM_SHORT] =
usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
/* 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.
*/
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));
/* 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)) {
chip->vendor.duration[TPM_SHORT] = HZ;
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);