diff options
Diffstat (limited to 'drivers/char/tpm/tpm-chip.c')
-rw-r--r-- | drivers/char/tpm/tpm-chip.c | 124 |
1 files changed, 121 insertions, 3 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 32db84683c40..8804c9e916fd 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -37,6 +37,103 @@ struct class *tpm_class; struct class *tpmrm_class; dev_t tpm_devt; +static int tpm_request_locality(struct tpm_chip *chip) +{ + int rc; + + if (!chip->ops->request_locality) + return 0; + + rc = chip->ops->request_locality(chip, 0); + if (rc < 0) + return rc; + + chip->locality = rc; + return 0; +} + +static void tpm_relinquish_locality(struct tpm_chip *chip) +{ + int rc; + + if (!chip->ops->relinquish_locality) + return; + + rc = chip->ops->relinquish_locality(chip, chip->locality); + if (rc) + dev_err(&chip->dev, "%s: : error %d\n", __func__, rc); + + chip->locality = -1; +} + +static int tpm_cmd_ready(struct tpm_chip *chip) +{ + if (!chip->ops->cmd_ready) + return 0; + + return chip->ops->cmd_ready(chip); +} + +static int tpm_go_idle(struct tpm_chip *chip) +{ + if (!chip->ops->go_idle) + return 0; + + return chip->ops->go_idle(chip); +} + +/** + * tpm_chip_start() - power on the TPM + * @chip: a TPM chip to use + * + * Return: + * * The response length - OK + * * -errno - A system error + */ +int tpm_chip_start(struct tpm_chip *chip) +{ + int ret; + + if (chip->ops->clk_enable) + chip->ops->clk_enable(chip, true); + + if (chip->locality == -1) { + ret = tpm_request_locality(chip); + if (ret) { + chip->ops->clk_enable(chip, false); + return ret; + } + } + + ret = tpm_cmd_ready(chip); + if (ret) { + tpm_relinquish_locality(chip); + if (chip->ops->clk_enable) + chip->ops->clk_enable(chip, false); + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(tpm_chip_start); + +/** + * tpm_chip_stop() - power off the TPM + * @chip: a TPM chip to use + * + * Return: + * * The response length - OK + * * -errno - A system error + */ +void tpm_chip_stop(struct tpm_chip *chip) +{ + tpm_go_idle(chip); + tpm_relinquish_locality(chip); + if (chip->ops->clk_enable) + chip->ops->clk_enable(chip, false); +} +EXPORT_SYMBOL_GPL(tpm_chip_stop); + /** * tpm_try_get_ops() - Get a ref to the tpm_chip * @chip: Chip to ref @@ -56,10 +153,17 @@ int tpm_try_get_ops(struct tpm_chip *chip) down_read(&chip->ops_sem); if (!chip->ops) + goto out_ops; + + mutex_lock(&chip->tpm_mutex); + rc = tpm_chip_start(chip); + if (rc) goto out_lock; return 0; out_lock: + mutex_unlock(&chip->tpm_mutex); +out_ops: up_read(&chip->ops_sem); put_device(&chip->dev); return rc; @@ -75,6 +179,8 @@ EXPORT_SYMBOL_GPL(tpm_try_get_ops); */ void tpm_put_ops(struct tpm_chip *chip) { + tpm_chip_stop(chip); + mutex_unlock(&chip->tpm_mutex); up_read(&chip->ops_sem); put_device(&chip->dev); } @@ -160,6 +266,7 @@ static void tpm_dev_release(struct device *dev) kfree(chip->log.bios_event_log); kfree(chip->work_space.context_buf); kfree(chip->work_space.session_buf); + kfree(chip->allocated_banks); kfree(chip); } @@ -189,7 +296,10 @@ static int tpm_class_shutdown(struct device *dev) if (chip->flags & TPM_CHIP_FLAG_TPM2) { down_write(&chip->ops_sem); - tpm2_shutdown(chip, TPM2_SU_CLEAR); + if (!tpm_chip_start(chip)) { + tpm2_shutdown(chip, TPM2_SU_CLEAR); + tpm_chip_stop(chip); + } chip->ops = NULL; up_write(&chip->ops_sem); } @@ -368,8 +478,12 @@ static void tpm_del_char_device(struct tpm_chip *chip) /* Make the driver uncallable. */ down_write(&chip->ops_sem); - if (chip->flags & TPM_CHIP_FLAG_TPM2) - tpm2_shutdown(chip, TPM2_SU_CLEAR); + if (chip->flags & TPM_CHIP_FLAG_TPM2) { + if (!tpm_chip_start(chip)) { + tpm2_shutdown(chip, TPM2_SU_CLEAR); + tpm_chip_stop(chip); + } + } chip->ops = NULL; up_write(&chip->ops_sem); } @@ -451,7 +565,11 @@ int tpm_chip_register(struct tpm_chip *chip) { int rc; + rc = tpm_chip_start(chip); + if (rc) + return rc; rc = tpm_auto_startup(chip); + tpm_chip_stop(chip); if (rc) return rc; |