1 files changed, 22 insertions, 10 deletions

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 8134f002b121..b1daa0d7b341 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -370,6 +370,13 @@ int tpm_pm_suspend(struct device *dev)
 	if (!chip)
 		return -ENODEV;
 
+	rc = tpm_try_get_ops(chip);
+	if (rc) {
+		/* Can be safely set out of locks, as no action cannot race: */
+		chip->flags |= TPM_CHIP_FLAG_SUSPENDED;
+		goto out;
+	}
+
 	if (chip->flags & TPM_CHIP_FLAG_ALWAYS_POWERED)
 		goto suspended;
 
@@ -377,21 +384,19 @@ int tpm_pm_suspend(struct device *dev)
 	    !pm_suspend_via_firmware())
 		goto suspended;
 
-	rc = tpm_try_get_ops(chip);
-	if (!rc) {
-		if (chip->flags & TPM_CHIP_FLAG_TPM2) {
-			tpm2_end_auth_session(chip);
-			tpm2_shutdown(chip, TPM2_SU_STATE);
-		} else {
-			rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
-		}
-
-		tpm_put_ops(chip);
+	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+		tpm2_end_auth_session(chip);
+		tpm2_shutdown(chip, TPM2_SU_STATE);
+		goto suspended;
 	}
 
+	rc = tpm1_pm_suspend(chip, tpm_suspend_pcr);
+
 suspended:
 	chip->flags |= TPM_CHIP_FLAG_SUSPENDED;
+	tpm_put_ops(chip);
 
+out:
 	if (rc)
 		dev_err(dev, "Ignoring error %d while suspending\n", rc);
 	return 0;
@@ -440,11 +445,18 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
 	if (!chip)
 		return -ENODEV;
 
+	/* Give back zero bytes, as TPM chip has not yet fully resumed: */
+	if (chip->flags & TPM_CHIP_FLAG_SUSPENDED) {
+		rc = 0;
+		goto out;
+	}
+
 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
 		rc = tpm2_get_random(chip, out, max);
 	else
 		rc = tpm1_get_random(chip, out, max);
 
+out:
 	tpm_put_ops(chip);
 	return rc;
 }