diff options
Diffstat (limited to 'drivers/char/tpm/tpm1-cmd.c')
| -rw-r--r-- | drivers/char/tpm/tpm1-cmd.c | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c index 3bd9f1fa77ce..8a84db315676 100644 --- a/drivers/char/tpm/tpm1-cmd.c +++ b/drivers/char/tpm/tpm1-cmd.c @@ -308,6 +308,40 @@ unsigned long tpm1_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal) return duration; } +#define TPM_ORD_STARTUP 153 +#define TPM_ST_CLEAR 1 + +/** + * tpm_startup() - turn on the TPM + * @chip: TPM chip to use + * + * Normally the firmware should start the TPM. This function is provided as a + * workaround if this does not happen. A legal case for this could be for + * example when a TPM emulator is used. + * + * Return: same as tpm_transmit_cmd() + */ +static int tpm1_startup(struct tpm_chip *chip) +{ + struct tpm_buf buf; + int rc; + + dev_info(&chip->dev, "starting up the TPM manually\n"); + + rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP); + if (rc < 0) + return rc; + + tpm_buf_append_u16(&buf, TPM_ST_CLEAR); + + rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0, + "attempting to start the TPM"); + + tpm_buf_destroy(&buf); + + return rc; +} + int tpm1_get_timeouts(struct tpm_chip *chip) { cap_t cap; @@ -317,7 +351,7 @@ int tpm1_get_timeouts(struct tpm_chip *chip) rc = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL, sizeof(cap.timeout)); if (rc == TPM_ERR_INVALID_POSTINIT) { - if (tpm_startup(chip)) + if (tpm1_startup(chip)) return rc; rc = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, @@ -727,3 +761,4 @@ int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr) return rc; } + |