security/tpm: remove tis_close()

This function was never called from outside of drivers and
src/drivers/pc80/tpm/tis.c was the only one doing it in a questionable
way.

tpm_vendor_cleanup() also isn't needed as one of tis_close() functions
was its only caller.

Change-Id: I9df76adfc21fca9fa1d1af7c40635ec0684ceb0f
Ticket: https://ticket.coreboot.org/issues/433
Signed-off-by: Sergii Dmytruk <sergii.dmytruk@3mdeb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/68989
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

src/drivers/crb/tis.c

@@ -53,19 +53,6 @@ int tis_open(void)
 	return 0;
 }
 
-int tis_close(void)
-{
-	if (tpm_is_open) {
-		/*
-		 * Do we need to do something here, like waiting for a
-		 * transaction to stop?
-		 */
-		tpm_is_open = 0;
-	}
-
-	return 0;
-}
-
 int tis_init(void)
 {
 	struct tpm2_info info;

src/drivers/i2c/tpm/cr50.c

@@ -494,10 +494,6 @@ int tpm_vendor_init(struct tpm_chip *chip, unsigned int bus, uint32_t dev_addr)
 	return 0;
 }
 
-void tpm_vendor_cleanup(struct tpm_chip *chip)
-{
-}
-
 enum cb_err tis_vendor_write(unsigned int addr, const void *buffer, size_t bytes)
 {
 	return cr50_i2c_write(addr & 0xff, buffer, bytes) ? CB_ERR : CB_SUCCESS;

src/drivers/i2c/tpm/tis.c

@@ -39,16 +39,6 @@ int tis_open(void)
 	return 0;
 }
 
-int tis_close(void)
-{
-	if (chip.is_open) {
-		tpm_vendor_cleanup(&chip);
-		chip.is_open = 0;
-	}
-
-	return 0;
-}
-
 int tis_init(void)
 {
 	return tpm_vendor_probe(CONFIG_DRIVER_TPM_I2C_BUS,

src/drivers/i2c/tpm/tis_atmel.c

@@ -27,11 +27,6 @@ int tis_open(void)
 	return 0;
 }
 
-int tis_close(void)
-{
-	return 0;
-}
-
 int tis_init(void)
 {
 	return 0;

src/drivers/i2c/tpm/tpm.c

@@ -550,8 +550,3 @@ out_err:
 	release_locality(chip, 0, 1);
 	return -1;
 }
-
-void tpm_vendor_cleanup(struct tpm_chip *chip)
-{
-	release_locality(chip, chip->vendor.locality, 1);
-}

src/drivers/i2c/tpm/tpm.h

@@ -61,6 +61,4 @@ int tpm_vendor_probe(unsigned int bus, uint32_t addr);
 
 int tpm_vendor_init(struct tpm_chip *chip, unsigned int bus, uint32_t dev_addr);
 
-void tpm_vendor_cleanup(struct tpm_chip *chip);
-
 #endif /* __DRIVERS_TPM_SLB9635_I2C_TPM_H__ */

src/drivers/pc80/tpm/tis.c

@@ -20,6 +20,7 @@
 #include <device/device.h>
 #include <console/console.h>
 #include <security/tpm/tis.h>
+#include <security/tpm/tss.h>
 #include <device/pnp.h>
 #include <drivers/tpm/tpm_ppi.h>
 #include <timer.h>
@@ -316,11 +317,6 @@ static int tis_wait_access(int locality, u8 mask, u8 expected)
 	return TPM_TIMEOUT_ERR;
 }
 
-static inline int tis_wait_dropped_access(int locality)
-{
-	return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY, 0);
-}
-
 static inline int tis_wait_received_access(int locality)
 {
 	return tis_wait_access(locality, TIS_ACCESS_ACTIVE_LOCALITY,
@@ -337,11 +333,6 @@ static inline void tis_request_access(int locality)
 	tpm_write_access(TIS_ACCESS_REQUEST_USE, locality);
 }
 
-static inline void tis_drop_access(int locality)
-{
-	tpm_write_access(TIS_ACCESS_ACTIVE_LOCALITY, locality);
-}
-
 /*
  * PC Client Specific TPM Interface Specification section 11.2.12:
  *
@@ -632,8 +623,7 @@ int tis_init(void)
 /*
  * tis_open()
  *
- * Requests access to locality 0 for the caller. After all commands have been
+ * Requests access to locality 0 for the caller.
- * completed the caller is supposed to call tis_close().
  *
  * Returns 0 on success, TPM_DRIVER_ERR on failure.
  */
@@ -641,49 +631,27 @@ int tis_open(void)
 {
 	u8 locality = 0; /* we use locality zero for everything */
 
-	if (tis_close())
+	if (!tis_has_access(locality)) {
-		return TPM_DRIVER_ERR;
+		/* request access to locality */
+		tis_request_access(locality);
 
-	/* now request access to locality */
+		/* did we get a lock? */
-	tis_request_access(locality);
+		if (tis_wait_received_access(locality)) {
+			printf("%s:%d - failed to lock locality %u\n",
+			__FILE__, __LINE__, locality);
+			return TPM_DRIVER_ERR;
+		}
 
-	/* did we get a lock? */
+		/* Certain TPMs seem to need some delay here or they hang... */
-	if (tis_wait_received_access(locality)) {
+		udelay(10);
-		printf("%s:%d - failed to lock locality %u\n",
-		       __FILE__, __LINE__, locality);
-		return TPM_DRIVER_ERR;
 	}
 
-	/* Certain TPMs seem to need some delay here or they hang... */
-	udelay(10);
-
 	if (tis_command_ready(locality) == TPM_TIMEOUT_ERR)
 		return TPM_DRIVER_ERR;
 
 	return 0;
 }
 
-/*
- * tis_close()
- *
- * terminate the current session with the TPM by releasing the locked
- * locality. Returns 0 on success of TPM_DRIVER_ERR on failure (in case lock
- * removal did not succeed).
- */
-int tis_close(void)
-{
-	u8 locality = 0;
-	if (tis_has_access(locality)) {
-		tis_drop_access(locality);
-		if (tis_wait_dropped_access(locality)) {
-			printf("%s:%d - failed to release locality %u\n",
-			       __FILE__, __LINE__, locality);
-			return TPM_DRIVER_ERR;
-		}
-	}
-	return 0;
-}
-
 /*
  * tis_sendrecv()
  *
@@ -727,10 +695,8 @@ int tis_sendrecv(const uint8_t *sendbuf, size_t send_size,
 static int tis_setup_interrupt(int vector, int polarity)
 {
 	u8 locality = 0;
-	int has_access = tis_has_access(locality);
 
-	/* Open connection and request access if not already granted */
+	if (tlcl_lib_init())
-	if (!has_access && tis_open() < 0)
 		return TPM_DRIVER_ERR;
 
 	/* Set TPM interrupt vector */
@@ -739,10 +705,6 @@ static int tis_setup_interrupt(int vector, int polarity)
 	/* Set TPM interrupt polarity and disable interrupts */
 	tpm_write_int_polarity(polarity, locality);
 
-	/* Close connection if it was opened */
-	if (!has_access && tis_close() < 0)
-		return TPM_DRIVER_ERR;
-
 	return 0;
 }
 

src/drivers/spi/tpm/tis.c

@@ -38,19 +38,6 @@ int tis_open(void)
 	return 0;
 }
 
-int tis_close(void)
-{
-	if (tpm_is_open) {
-		/*
-		 * Do we need to do something here, like waiting for a
-		 * transaction to stop?
-		 */
-		tpm_is_open = 0;
-	}
-
-	return 0;
-}
-
 int tis_init(void)
 {
 	struct spi_slave spi;

src/security/tpm/tis.h

@@ -44,22 +44,12 @@ int tis_init(void);
 /*
  * tis_open()
  *
- * Requests access to locality 0 for the caller. After all commands have been
+ * Requests access to locality 0 for the caller.
- * completed the caller is supposed to call tis_close().
  *
  * Returns 0 on success, -1 on failure.
  */
 int tis_open(void);
 
-/*
- * tis_close()
- *
- * terminate the current session with the TPM by releasing the locked
- * locality. Returns 0 on success of -1 on failure (in case lock
- * removal did not succeed).
- */
-int tis_close(void);
-
 /*
  * tis_sendrecv()
  *