tpm: suppress durations sysfs output if not read

Suppress the output in the 'durations' sysfs entry if they were not read during driver initialization. This is similar to other sysfs entries that return nothing if for some reason sending the commands to the TPM fails. Signed-off-by: Stefan Berger <[email protected]> Signed-off-by: James Morris <[email protected]>
goeke · Aug 23, 2011 · 403d1d0 · 403d1d0
1 parent 8ad346c
commit 403d1d0
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
@@ -963,6 +963,9 @@ ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
 {
 	struct tpm_chip *chip = dev_get_drvdata(dev);
 
+	if (chip->vendor.duration[TPM_LONG] == 0)
+		return 0;
+
 	return sprintf(buf, "%d %d %d [%s]\n",
 		       jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
 		       jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),