tpm: Factor out common startup code

The TCG standard startup sequence (get timeouts, tpm startup, etc) for
TPM and TPM2 chips is being open coded in many drivers, move it into
the core code.

tpm_tis and tpm_crb are used as the basis for the core code
implementation and the easy drivers are converted. In the process
several small drivers bugs relating to error handling this flow
are fixed.

For now the flag TPM_OPS_AUTO_STARTUP is optional to allow a staged
driver roll out, but ultimately all drivers should use this flow and
the flag removed. Some drivers still do not implement the startup
sequence at all and will need to be tested with it enabled.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Tested-by: Andrew Zamansky <andrew.zamansky@nuvoton.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

1 files changed, 42 insertions, 4 deletions

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index a88b31e7fe72..08c7e23ed535 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -728,7 +728,7 @@ static const struct tpm_input_header tpm2_startup_header = {
  * returned it remarks a POSIX error code. If a positive number is returned
  * it remarks a TPM error.
  */
-int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
+static int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
 {
 	struct tpm2_cmd cmd;
 
@@ -738,7 +738,6 @@ int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
 	return tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 				"attempting to start the TPM");
 }
-EXPORT_SYMBOL_GPL(tpm2_startup);
 
 #define TPM2_SHUTDOWN_IN_SIZE \
 	(sizeof(struct tpm_input_header) + \
@@ -854,7 +853,7 @@ static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
  * returned it remarks a POSIX error code. If a positive number is returned
  * it remarks a TPM error.
  */
-int tpm2_do_selftest(struct tpm_chip *chip)
+static int tpm2_do_selftest(struct tpm_chip *chip)
 {
 	int rc;
 	unsigned int loops;
@@ -894,7 +893,6 @@ int tpm2_do_selftest(struct tpm_chip *chip)
 
 	return rc;
 }
-EXPORT_SYMBOL_GPL(tpm2_do_selftest);
 
 /**
  * tpm2_gen_interrupt() - generate an interrupt
@@ -942,3 +940,43 @@ int tpm2_probe(struct tpm_chip *chip)
 	return 0;
 }
 EXPORT_SYMBOL_GPL(tpm2_probe);
+
+/**
+ * tpm2_auto_startup - Perform the standard automatic TPM initialization
+ *                     sequence
+ * @chip: TPM chip to use
+ *
+ * Returns 0 on success, < 0 in case of fatal error.
+ */
+int tpm2_auto_startup(struct tpm_chip *chip)
+{
+	int rc;
+
+	rc = tpm_get_timeouts(chip);
+	if (rc)
+		goto out;
+
+	rc = tpm2_do_selftest(chip);
+	if (rc != TPM2_RC_INITIALIZE) {
+		dev_err(&chip->dev, "TPM self test failed\n");
+		goto out;
+	}
+
+	if (rc == TPM2_RC_INITIALIZE) {
+		rc = tpm2_startup(chip, TPM2_SU_CLEAR);
+		if (rc)
+			goto out;
+
+		rc = tpm2_do_selftest(chip);
+		if (rc) {
+			dev_err(&chip->dev, "TPM self test failed\n");
+			goto out;
+		}
+	}
+
+	return rc;
+out:
+	if (rc > 0)
+		rc = -ENODEV;
+	return rc;
+}