Refuse activation of tpm_tis driver if TPM is not working correctly

Refuse activation of tpm_tis driver if the TPM is found not to be working correctly. This prevents suspend/resume problems for me on Lenovo W500 and T61p.

Signed-off-by Stefan Berger<[email protected]>

---
  drivers/char/tpm/tpm_tis.c |   13 +++++++++++++
  1 files changed, 13 insertions(+), 0 deletions(-)

drivers/char/tpm/tpm_tis.c +13 -0

index 3f4051a..7f2761d 100644
@@ -549,6 +549,7 @@ static int tpm_tis_init(struct device *dev, resource_size_t start,
  	u32 vendor, intfcaps, intmask;
  	int rc, i, irq_s, irq_e;
  	struct tpm_chip *chip;
+	u8 digest[TPM_DIGEST_SIZE];
 
  	if (!(chip = tpm_register_hardware(dev,&tpm_tis)))
  		return -ENODEV;

@@ -616,6 +617,18 @@ static int tpm_tis_init(struct device *dev, resource_size_t start,
  	/* get the timeouts before testing for irqs */
  	tpm_get_timeouts(chip);
 
+	/* test for correctly working TPM; refuse driver if not working
+	   to prevent suspend/resume problems */
+	rc = tpm_pcr_read(chip->dev_num, 0, digest);
+	if (rc != 0) {
+		dev_err(dev, "Could not read PCR 0. "
+			"TPM is not working correctly.\n");
+		dev_err(dev, "Was machine previously suspended without TPM "
+			"driver present?\n");
+		rc = -ENODEV;
+		goto out_err;
+	}
+
  	/* INTERRUPT Setup */
  	init_waitqueue_head(&chip->vendor.read_queue);
  	init_waitqueue_head(&chip->vendor.int_queue);

Quoted 5 lines · Stefan Berger

Refuse activation of tpm_tis driver if the TPM is found not to be working correctly. This prevents suspend/resume problems for me on Lenovo W500 and T61p.

Signed-off-by Stefan Berger<[email protected]>

Testing and trying to reproduce it here.