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path: root/drivers/char/tpm/tpm-chip.c
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Diffstat (limited to 'drivers/char/tpm/tpm-chip.c')
-rw-r--r--drivers/char/tpm/tpm-chip.c124
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;