4 files changed, 26 insertions, 21 deletions

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 3f27753d96aa..7a4869151d3b 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -346,7 +346,7 @@ int tpm_chip_register(struct tpm_chip *chip)
 	tpm_sysfs_add_device(chip);
 
 	rc = tpm_bios_log_setup(chip);
-	if (rc == -ENODEV)
+	if (rc != 0 && rc != -ENODEV)
 		return rc;
 
 	tpm_add_ppi(chip);
diff --git a/drivers/char/tpm/tpm_acpi.c b/drivers/char/tpm/tpm_acpi.c
index 0cb43ef5f79a..b7718c95fd0b 100644
--- a/drivers/char/tpm/tpm_acpi.c
+++ b/drivers/char/tpm/tpm_acpi.c
@@ -56,12 +56,18 @@ int tpm_read_log_acpi(struct tpm_chip *chip)
 
 	log = &chip->log;
 
+	/* Unfortuntely ACPI does not associate the event log with a specific
+	 * TPM, like PPI. Thus all ACPI TPMs will read the same log.
+	 */
+	if (!chip->acpi_dev_handle)
+		return -ENODEV;
+
 	/* Find TCPA entry in RSDT (ACPI_LOGICAL_ADDRESSING) */
 	status = acpi_get_table(ACPI_SIG_TCPA, 1,
 				(struct acpi_table_header **)&buff);
 
 	if (ACPI_FAILURE(status))
-		return -EIO;
+		return -ENODEV;
 
 	switch(buff->platform_class) {
 	case BIOS_SERVER:
diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
index 34f0921f0203..c73f88cdeadf 100644
--- a/drivers/char/tpm/tpm_eventlog.c
+++ b/drivers/char/tpm/tpm_eventlog.c
@@ -368,14 +368,21 @@ static int tpm_read_log(struct tpm_chip *chip)
 	}
 
 	rc = tpm_read_log_acpi(chip);
-	if ((rc == 0) || (rc == -ENOMEM))
+	if (rc != -ENODEV)
 		return rc;
 
-	rc = tpm_read_log_of(chip);
-
-	return rc;
+	return tpm_read_log_of(chip);
 }
 
+/*
+ * tpm_bios_log_setup() - Read the event log from the firmware
+ * @chip: TPM chip to use.
+ *
+ * If an event log is found then the securityfs files are setup to
+ * export it to userspace, otherwise nothing is done.
+ *
+ * Returns -ENODEV if the firmware has no event log.
+ */
 int tpm_bios_log_setup(struct tpm_chip *chip)
 {
 	const char *name = dev_name(&chip->dev);
@@ -386,15 +393,8 @@ int tpm_bios_log_setup(struct tpm_chip *chip)
 		return 0;
 
 	rc = tpm_read_log(chip);
-	/*
-	 * read_log failure means event log is not supported except for ENOMEM.
-	 */
-	if (rc < 0) {
-		if (rc == -ENOMEM)
-			return -ENODEV;
-		else
-			return rc;
-	}
+	if (rc)
+		return rc;
 
 	cnt = 0;
 	chip->bios_dir[cnt] = securityfs_create_dir(name, NULL);
diff --git a/drivers/char/tpm/tpm_of.c b/drivers/char/tpm/tpm_of.c
index 36df9df4c472..7dee42d7b5e0 100644
--- a/drivers/char/tpm/tpm_of.c
+++ b/drivers/char/tpm/tpm_of.c
@@ -29,13 +29,16 @@ int tpm_read_log_of(struct tpm_chip *chip)
 	struct tpm_bios_log *log;
 
 	log = &chip->log;
-	if (chip->dev.parent->of_node)
+	if (chip->dev.parent && chip->dev.parent->of_node)
 		np = chip->dev.parent->of_node;
 	else
 		return -ENODEV;
 
 	sizep = of_get_property(np, "linux,sml-size", NULL);
-	if (sizep == NULL)
+	basep = of_get_property(np, "linux,sml-base", NULL);
+	if (sizep == NULL && basep == NULL)
+		return -ENODEV;
+	if (sizep == NULL || basep == NULL)
 		return -EIO;
 
 	if (*sizep == 0) {
@@ -43,10 +46,6 @@ int tpm_read_log_of(struct tpm_chip *chip)
 		return -EIO;
 	}
 
-	basep = of_get_property(np, "linux,sml-base", NULL);
-	if (basep == NULL)
-		return -EIO;
-
 	log->bios_event_log = kmalloc(*sizep, GFP_KERNEL);
 	if (!log->bios_event_log)
 		return -ENOMEM;