tpm: fix (ACPI S3) suspend regression
This patch fixes an (ACPI S3) suspend regression introduced in commit
68d6e6713fcb ("tpm: Introduce function to poll for result of self test")
and occurring with an Infineon TPM and tpm_tis and tpm_infineon drivers
active.
The suspend problem occurred if the TPM was disabled and/or deactivated
and therefore the TPM_PCRRead checking the result of the (asynchronous)
self test returned an error code which then caused the tpm_tis driver to
become inactive and this then seemed to have negatively influenced the
suspend support by the tpm_infineon driver... Besides that the tpm_tis
drive may stay active even if the TPM is disabled and/or deactivated.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Tested-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 6a8771f..32362cf 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -846,6 +846,15 @@
do {
rc = __tpm_pcr_read(chip, 0, digest);
+ if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
+ dev_info(chip->dev,
+ "TPM is disabled/deactivated (0x%X)\n", rc);
+ /* TPM is disabled and/or deactivated; driver can
+ * proceed and TPM does handle commands for
+ * suspend/resume correctly
+ */
+ return 0;
+ }
if (rc != TPM_WARN_DOING_SELFTEST)
return rc;
msleep(delay_msec);
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 8c1df30..0105471 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -39,6 +39,9 @@
};
#define TPM_WARN_DOING_SELFTEST 0x802
+#define TPM_ERR_DEACTIVATED 0x6
+#define TPM_ERR_DISABLED 0x7
+
#define TPM_HEADER_SIZE 10
extern ssize_t tpm_show_pubek(struct device *, struct device_attribute *attr,
char *);
