[PATCH] tpm: add debugging output

Signed-off-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 726d1b5..785dce6 100644 (file)
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -146,8 +146,12 @@ ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 
        memcpy(data, cap_pcr, sizeof(cap_pcr));
        if ((len = tpm_transmit(chip, data, sizeof(data)))
-           < CAP_PCR_RESULT_SIZE)
-               return len;
+           < CAP_PCR_RESULT_SIZE) {
+               dev_err(&chip->pci_dev->dev, "A TPM error (%d) occurred "
+                               "attempting to determine the number of PCRS\n",
+                       be32_to_cpu(*((__be32 *) (data + 6))));
+               return 0;
+       }
 
        num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
 
@@ -156,16 +160,20 @@ ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
                index = cpu_to_be32(i);
                memcpy(data + 10, &index, 4);
                if ((len = tpm_transmit(chip, data, sizeof(data)))
-                   < READ_PCR_RESULT_SIZE)
-                       return len;
+                   < READ_PCR_RESULT_SIZE){
+                       dev_err(&chip->pci_dev->dev, "A TPM error (%d) occurred"
+                               " attempting to read PCR %d of %d\n",
+                               be32_to_cpu(*((__be32 *) (data + 6))), i, num_pcrs);
+                       goto out;
+               }
                str += sprintf(str, "PCR-%02d: ", i);
                for (j = 0; j < TPM_DIGEST_SIZE; j++)
                        str += sprintf(str, "%02X ", *(data + 10 + j));
                str += sprintf(str, "\n");
        }
+out:
        return str - buf;
 }
-
 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 
 #define  READ_PUBEK_RESULT_SIZE 314
@@ -197,8 +205,10 @@ ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 
        if ((len = tpm_transmit(chip, data, READ_PUBEK_RESULT_SIZE)) <
            READ_PUBEK_RESULT_SIZE) {
-               rc = len;
-               goto out;
+               dev_err(&chip->pci_dev->dev, "A TPM error (%d) occurred "
+                               "attempting to read the PUBEK\n",
+                           be32_to_cpu(*((__be32 *) (data + 6))));
+               return 0;
        }
 
        /* 
@@ -230,7 +240,6 @@ ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
                        str += sprintf(str, "\n");
        }
        rc = str - buf;
-out:
        kfree(data);
        return rc;
 }